nx_wgsl_canonical_skin_t140.nx source
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1// nx_wgsl.nx -- THE SHADER BACKENDS: NishiLang in, GLSL and WGSL out.
2//
3// CONTRACT SYMBOL: wgsl_emit_module (declared _ABSENT_ on the graphics compare board until now).
4//
5// THE SOURCE IS NISHILANG, NOT GLSL (operator 2026-08-23). This organ is NOT a GLSL->WGSL
6// transpiler. A shader is authored ONCE against the nx_shader_ir representation; glsl_emit_module
7// and wgsl_emit_module are two BACKENDS over that one source, exactly as nx_compile_x86 and the
8// WAT lane are two backends over one NishiLang front-end. Neither dialect is authored, so neither
9// can drift from the other -- disagreement is impossible BY CONSTRUCTION rather than by discipline.
10//
11// RUNG 1, SHIPPED HERE: the fullscreen-triangle VERTEX STAGE. It is not a toy -- it is the exact
12// stage that ships TODAY, hand-written TWICE in nx_game_page_emit:
13// GLSL VSH : void main(){vec2 v=vec2((gl_VertexID<<1)&2,gl_VertexID&2);gl_Position=vec4(v*2.-1.,0.,1.);}
14// WGSL vs : @vertex fn vs(@builtin(vertex_index) vi:u32)->@builtin(position) vec4f{...}
15// Those two hand copies are the duplication this rung deletes: below, ONE NishiLang source
16// (shsrc_fullscreen_tri) emits both.
17//
18// WHY THIS STAGE PROVES THE THESIS. The two dialects are not spelling variants of each other:
19// * GLSL ASSIGNS gl_Position; WGSL RETURNS @builtin(position). Different STRUCTURE.
20// * GLSL gl_VertexID is i32; WGSL vertex_index is u32 and must be converted before i32 maths.
21// * WGSL requires a u32 shift amount (1u); GLSL takes a plain int.
22// * WGSL requires 0.0, never 0. ; GLSL accepts either.
23// Every one of those is dialect knowledge the BACKEND owns. A translator would have to rediscover
24// them from GLSL text; a backend simply knows them, once.
25//
26// COVERED SUBSET (rung 1) -- anything outside REFUSES BY NAME via sir_refuse and returns -1.
27// A NAMED REFUSAL IS A CONTRACT; A SILENT MISTRANSLATION IN A SHADER BACKEND IS THE WORST
28// AVAILABLE FAILURE: it compiles, it links, it runs, and it draws the wrong picture forever.
29// decls : uniform (scalar + array); attribute and varying are GLSL-covered and, since S1
30// (2026-09-04), WGSL-REFUSED BY NAME (K_ATTRIB anywhere, K_VARY in a fragment stage) until
31// the entry-parameter derivation that WGSL needs for them lands; a texture-typed uniform
32// refuses in WGSL too -- it was being emitted INSIDE struct U
33// S3 (2026-09-04): a TEXTURE is its own kind (K_TEXTURE / sir_texture) in BOTH backends: GLSL
34// `uniform highp usampler3D`, WGSL a @group/@binding var OUTSIDE struct U with its binding
35// DERIVED from declaration order; only texture_3d<u32> is covered, other texture types refuse
36// S4 (2026-09-04): the FRAGMENT entry signature is DERIVED from the declared parameters (no
37// longer a literal): a sir_param_position parameter is `@builtin(position) name:vec4f` in WGSL and
38// gl_FragCoord in GLSL; a position READ with no such parameter, and any entry parameter a backend
39// cannot bind (plain fragment params, any vertex/compute param), refuse by name
40// stmts : var, assign, return, if/else, discard
41// exprs : literal, identifier, binary op, call, constructor, swizzle, index, cast, builtin,
42// texture load, texture sample
43// types : f32 i32 u32 bool vec2f vec3f vec4f vec3i texture_3d<u32> texture_2d<f32>
44// NOT covered (each REFUSES, and each is a named rung): matrices, structs, arrays of vectors as
45// locals, derivatives. Loops/break landed as rung 2b-general.
46//
47// RUNG GE43 (gameengine board, 2026-09-02) -- THE COMPUTE STAGE, WGSL-DOOR ONLY. Storage buffers
48// (read / read_write, optionally atomic<>), atomic read-modify-write (atomicMin/Max/Add, the
49// backend supplies the `&`), the global_invocation_id builtin, and the @compute entry with its
50// @workgroup_size. This is the first byte of the ONE NishiLang rasterizer kernel the board declares
51// (GE42 rk_kernel_ir -> GE43 wgsl_compute_stage -> GE44 rk_webgpu_door -> GE45 rk_tier_ladder):
52// the kernel is authored HERE, once, and reaches a third-party browser through WebGPU as a pure
53// submission pipe, and NishiOS through the dxg lane. GLSL ES 3.00 (WebGL2) has no compute stage,
54// no storage buffers and no atomics, so the GLSL backend REFUSES every one of these BY NAME --
55// `nx_wgsl compute` prints both outcomes and nx_wgsl_compute_gate asserts the bytes exactly.
56
57import "nx_syscalls.nx"
58import "nx_shader_ir.nx"
59import "nx_cast_shader_src.nx" // S12c (2026-09-05): THE CHARACTER CAST vertex stage written once, transcribed slice by slice and measured against the hand MVS by nx_glsl_tokdiff (verb: cast)
60import "nx_world_shader_src.nx" // GE44 R-G (2026-09-04): THE WORLD SHADER written once; `nx_wgsl world` emits it to both dialects
61// RUNG 2 -- SHARE THE FRONT-END, DO NOT FORK IT. These are exactly the imports nx_compile_wat.nx
62// uses for the WAT backend. A shader is compiled by the SAME lexer, the SAME parser and the SAME
63// optimiser as every other NishiLang program; this organ is one more BACKEND hanging off that
64// front-end, beside nx_compile_x86 and nx_wasm. Two parsers for one language would be the
65// duplicate-ruler defect at the worst possible layer, so there is not a second one anywhere here.
66import "nx_types.nx"
67import "nx_lex_kinds.nx"
68import "nx_ir.nx"
69import "nx_tokenizer.nx"
70import "nx_parse.nx"
71import "nx_opt.nx"
72import "nx_import.nx"
73
74// STAGE_PLAIN is rung 2: an ORDINARY NishiLang function, compiled through the REAL front-end
75// (expand_imports -> lex_source -> parse_module -> opt_run) and emitted as a plain shader
76// function with its own parameters and return type. Rung 1's stages wrap an entry point; this
77// one wraps nothing, because the source is the language itself.
78const STAGE_PLAIN: i64 = 0
79const STAGE_VERTEX: i64 = 1
80const STAGE_FRAGMENT: i64 = 2
81// GE43: the compute stage. WGSL only -- glsl_emit_module refuses it by name before emitting a byte.
82const STAGE_COMPUTE: i64 = 3
83// Invocations per workgroup on the compute entry. 64 is the width both vendor wavefronts divide
84// evenly (AMD wave64, NVIDIA warp32) and one quarter of WebGPU's default
85// maxComputeInvocationsPerWorkgroup of 256 (the limit is banked as a GE42 lesson row on the
86// gameengine board). Named here so a kernel author never spells the geometry by hand.
87const WG_WORKGROUP: i64 = 64
88
89// Buffer bounds, DERIVED from the IR's own cap rather than picked -- ONE OWNER for the number.
90// A trace records at most one entry per IR node, so its ceiling IS the node ceiling.
91const WG_TRACE_CAP: i64 = SIR_MAXNODE
92// The emitted-text buffer. Every node in the covered subset emits a bounded run of characters --
93// the longest single emission is a type name plus punctuation -- so 16 bytes per representable
94// node is a ceiling no module the IR can hold is able to exceed.
95const WG_EMIT_CAP: i64 = SIR_MAXNODE * 16
96// S12c-4: the '!' byte, constructed because the nx_cc lexer refuses a bang inside a string literal
97const WG_C_BANG: i64 = 33
98// Decimal rendering of an i64 needs at most 20 digits plus sign plus terminator.
99const WG_NUMBUF: i64 = 32
100// R-A: the select operands are emitted in IR order and rotated in place by wg_rev -- no scratch buffer, nothing
101// to size (a WG_SEL_SCRATCH constant lived here for one build on 2026-09-04 and was retired before it was used).
102// A REFUSAL MESSAGE IS NOT A NUMBER, AND SIZING IT LIKE ONE TRUNCATES THE ACTIONABLE HALF.
103// Measured on this organ's own first rung-2 run: the refusal printed "opcode outside the covered
104// subs" -- the opcode NUMBER, the only part a reader can act on, fell off the end of a 32-byte
105// buffer named for decimal digits. A named refusal that cannot finish naming is the contract
106// failing in the one place it exists to hold.
107const WG_MSGBUF: i64 = 128
108// S3 (2026-09-04): THE WGSL BINDING LAYOUT, owned here and nowhere else. Every resource lives in ONE bind
109// group. struct U (all uniforms) sits at WG_BIND_UNIFORM whether or not a module declares a uniform, so
110// adding one later never renumbers the resources beside it. Textures take the bindings after struct U in
111// DECLARATION ORDER (first K_TEXTURE = WG_BIND_TEX_FIRST, then +1, ...). A storage buffer carries an
112// EXPLICIT binding (sir_storage); a derived texture binding that lands on one REFUSES by name rather than
113// emitting two vars on one slot.
114const WG_BIND_GROUP: i64 = 0
115// S12 step 2 (2026-09-06): the group a module's resources are spelled in = the base group plus the module's own word
116// (M_BINDGROUP, 0 unless a verb sets it). Every @group( emitter reads THIS, so a module moved to another group moves
117// its struct U, textures, samplers and storage buffers together -- one speller, no site left behind.
118func wg_group(m: *i64) -> i64 { return WG_BIND_GROUP + m[M_BINDGROUP] }
119const WG_BIND_UNIFORM: i64 = 0
120const WG_BIND_TEX_FIRST: i64 = WG_BIND_UNIFORM + 1
121
122// ---- dialect type spelling ----------------------------------------------------------------
123func gl_ty(t: i64) -> *u8 {
124 if t == T_VOID { return "void" as *u8 }
125 if t == T_F32 { return "float" as *u8 }
126 if t == T_I32 { return "int" as *u8 }
127 if t == T_U32 { return "uint" as *u8 }
128 if t == T_BOOL { return "bool" as *u8 }
129 if t == T_V2F { return "vec2" as *u8 }
130 if t == T_V3F { return "vec3" as *u8 }
131 if t == T_V4F { return "vec4" as *u8 }
132 if t == T_V3I { return "ivec3" as *u8 }
133 if t == T_V2I { return "ivec2" as *u8 }
134 if t == T_M3F { return "mat3" as *u8 }
135 if t == T_TEX3U { return "highp usampler3D" as *u8 }
136 if t == T_TEX2F { return "sampler2D" as *u8 }
137 if t == T_TEX2F { return "sampler2D" as *u8 }
138 if t == T_V3U { return "uvec3" as *u8 }
139 return 0 as *u8
140}
141
142func wg_ty(t: i64) -> *u8 {
143 if t == T_VOID { return "void" as *u8 }
144 if t == T_F32 { return "f32" as *u8 }
145 if t == T_I32 { return "i32" as *u8 }
146 if t == T_U32 { return "u32" as *u8 }
147 if t == T_BOOL { return "bool" as *u8 }
148 if t == T_V2F { return "vec2f" as *u8 }
149 if t == T_V3F { return "vec3f" as *u8 }
150 if t == T_V4F { return "vec4f" as *u8 }
151 if t == T_V3I { return "vec3i" as *u8 }
152 if t == T_V2I { return "vec2i" as *u8 }
153 if t == T_M3F { return "mat3x3f" as *u8 }
154 if t == T_TEX3U { return "texture_3d<u32>" as *u8 }
155 if t == T_TEX2F { return "texture_2d<f32>" as *u8 }
156 if t == T_TEX2F { return "texture_2d<f32>" as *u8 }
157 if t == T_V3U { return "vec3u" as *u8 }
158 return 0 as *u8
159}
160
161// R-D (2026-09-04): a STRUCT type is spelled by its declaration's name in BOTH dialects; scalars and vectors keep
162// each dialect's table. ONE lookup (sir_struct_of) decides which declaration a type names, so the two backends
163// cannot disagree about it. A caller that spells a type through these never meets a struct as "outside the
164// covered subset".
165func gl_tyname(m: *i64, t: i64) -> *u8 {
166 let st: i64 = sir_struct_of(m, t)
167 if st != 0 { return sir_cstr(m, sir_get(m, st, SIR_NAME)) }
168 return gl_ty(t)
169}
170func wg_tyname(m: *i64, t: i64) -> *u8 {
171 let st: i64 = sir_struct_of(m, t)
172 if st != 0 { return sir_cstr(m, sir_get(m, st, SIR_NAME)) }
173 return wg_ty(t)
174}
175
176// A texture type is a BOUND RESOURCE in both dialects (a sampler uniform in GLSL, a @binding var in
177// WGSL), never a value type: it cannot be a struct member, a local, a parameter or a cast target.
178// ONE predicate for that class, so the two backends cannot disagree about which types it holds.
179func wg_is_texty(t: i64) -> i64 {
180 if t == T_TEX3U { return 1 }
181 if t == T_TEX2F { return 1 }
182 return 0
183}
184
185// ---- IDENTIFIER RESOLUTION (S2, 2026-09-04) ----------------------------------------------------
186// An E_IDENT carries only a NAME; what it names decides how each dialect spells it. WGSL folds every
187// uniform into `struct U` behind ONE binding, so a uniform read must be spelled `u.<name>` -- before S2
188// the backend emitted the bare name, an undeclared identifier in WGSL, with no refusal (measured on the
189// S1 positive control: `v=(v*scale);` under a `struct U{scale:f32,}`). Resolution order is the
190// language's own: a parameter or local of the CURRENT function (M_CURFN, set by both backends) shadows a
191// module-scope declaration. Names are pool offsets interned per call, so identity is by CONTENT.
192func wg_name_is(m: *i64, id: i64, name: *u8) -> i64 {
193 return wg_streq(sir_cstr(m, sir_get(m, id, SIR_NAME)), name)
194}
195// the K_PARAM of this name on the function, or 0
196func wg_fn_param(m: *i64, fn: i64, name: *u8) -> i64 {
197 if fn == 0 { return 0 }
198 var p: i64 = sir_get(m, fn, SIR_A)
199 while p != 0 {
200 if wg_name_is(m, p, name) == 1 { return p }
201 p = sir_get(m, p, SIR_NEXT)
202 }
203 return 0
204}
205// S4: the K_PARAM bound to @builtin(position) on the function, or 0
206func wg_fn_position_param(m: *i64, fn: i64) -> i64 {
207 if fn == 0 { return 0 }
208 var p: i64 = sir_get(m, fn, SIR_A)
209 while p != 0 {
210 if sir_get(m, p, SIR_A) == P_BUILTIN_POSITION { return p }
211 p = sir_get(m, p, SIR_NEXT)
212 }
213 return 0
214}
215// 1 iff a statement chain -- recursively through if arms and loop bodies -- declares an S_VAR of this name
216func wg_chain_local(m: *i64, head: i64, name: *u8) -> i64 {
217 var s: i64 = head
218 while s != 0 {
219 let k: i64 = sir_get(m, s, SIR_KIND)
220 if k == S_VAR { if wg_name_is(m, s, name) == 1 { return 1 } }
221 if k == S_IF {
222 if wg_chain_local(m, sir_get(m, s, SIR_B), name) == 1 { return 1 }
223 if wg_chain_local(m, sir_get(m, s, SIR_C), name) == 1 { return 1 }
224 }
225 if k == S_LOOP { if wg_chain_local(m, sir_get(m, s, SIR_A), name) == 1 { return 1 } }
226 s = sir_get(m, s, SIR_NEXT)
227 }
228 return 0
229}
230// the module-scope declaration of this KIND with this name, or 0
231func wg_decl_named(m: *i64, kind: i64, name: *u8) -> i64 {
232 var d: i64 = m[M_DECLH]
233 while d != 0 {
234 if sir_get(m, d, SIR_KIND) == kind { if wg_name_is(m, d, name) == 1 { return d } }
235 d = sir_get(m, d, SIR_NEXT)
236 }
237 return 0
238}
239// 1 iff the name, read inside the function being emitted, resolves to a module-scope K_UNIFORM --
240// i.e. no parameter and no local of the current function shadows it.
241func wg_resolves_to_uniform(m: *i64, name: *u8) -> i64 {
242 let fn: i64 = m[M_CURFN]
243 if wg_fn_param(m, fn, name) != 0 { return 0 }
244 if fn != 0 { if wg_chain_local(m, sir_get(m, fn, SIR_B), name) == 1 { return 0 } }
245 if wg_decl_named(m, K_UNIFORM, name) != 0 { return 1 }
246 return 0
247}
248// S7 (2026-09-05): the varying twin of the resolver above -- a bare identifier that no parameter and no
249// local of the current function shadows, resolving to a module-scope K_VARY. The caller spells the
250// qualifier (vo. in the vertex entry, vin. in the fragment entry) from M_VIOMODE.
251func wg_resolves_to_varying(m: *i64, name: *u8) -> i64 {
252 let fn: i64 = m[M_CURFN]
253 if wg_fn_param(m, fn, name) != 0 { return 0 }
254 if fn != 0 { if wg_chain_local(m, sir_get(m, fn, SIR_B), name) == 1 { return 0 } }
255 if wg_decl_named(m, K_VARY, name) != 0 { return 1 }
256 return 0
257}
258
259// ---- S12c-2b (2026-09-05): A float[N] UNIFORM IS CARRIED AS array<vec4f,ceil(N/4)> -----------------------
260// The uniform address space requires a 16-byte array stride (the layout ruler refuses array<f32,N> by name), and the cast
261// declares uOF/uGB/uGT/uGN as float[12] exactly as its GLSL does. ONE rule, read by the struct-U emitter, the E_INDEX arm and
262// the layout ruler: the member is array<vec4f,ceil(N/4)> and the read is u.name[i/4][i%4]. GLSL is untouched (float name[N],
263// name[i]) so the token proof against the hand text is unaffected. The lane count is DERIVED here, never typed at a use site.
264const WG_F32ARR_LANES: i64 = 4
265func wg_f32arr_vec4n(n: i64) -> i64 { return (n + WG_F32ARR_LANES - 1) / WG_F32ARR_LANES }
266// N when `name` resolves (unshadowed) to a module-scope K_UNIFORM float[N] with N>0; 0 otherwise
267func wg_f32arr_len(m: *i64, name: *u8) -> i64 {
268 if wg_resolves_to_uniform(m, name) == 0 { return 0 }
269 let d: i64 = wg_decl_named(m, K_UNIFORM, name)
270 if d == 0 { return 0 }
271 if sir_get(m, d, SIR_TY) != T_F32 { return 0 }
272 return sir_get(m, d, SIR_A)
273}
274
275// ---- S5 (2026-09-04): THE FRAGMENT OUTPUT ---------------------------------------------------------
276// the FIRST declaration of this kind, or 0
277func wg_decl_kind_first(m: *i64, kind: i64) -> i64 {
278 var d: i64 = m[M_DECLH]
279 while d != 0 {
280 if sir_get(m, d, SIR_KIND) == kind { return d }
281 d = sir_get(m, d, SIR_NEXT)
282 }
283 return 0
284}
285// how many declarations of this kind the module carries
286func wg_decl_kind_count(m: *i64, kind: i64) -> i64 {
287 var n: i64 = 0
288 var d: i64 = m[M_DECLH]
289 while d != 0 {
290 if sir_get(m, d, SIR_KIND) == kind { n = n + 1 }
291 d = sir_get(m, d, SIR_NEXT)
292 }
293 return n
294}
295// the module's declared fragment output, or 0. ONE lookup, so the two backends cannot disagree
296// about which declaration is the output -- the duplicate-ruler defect at the worst possible layer.
297func wg_fragout(m: *i64) -> i64 { return wg_decl_kind_first(m, K_FRAGOUT) }
298// 1 iff a statement chain -- recursively through if arms and loop bodies -- carries an S_RETURN that
299// returns a VALUE. The output requirement binds to what the body DOES, not to the stage: a fragment
300// that only discards is a legal program with no colour output, and a guard that refused it would be a
301// false-positive generator. This is the cheapest exact test, and it reuses wg_chain_local's shape.
302func wg_chain_returns_value(m: *i64, head: i64) -> i64 {
303 var s: i64 = head
304 while s != 0 {
305 let k: i64 = sir_get(m, s, SIR_KIND)
306 if k == S_RETURN { if sir_get(m, s, SIR_A) != 0 { return 1 } }
307 if k == S_IF {
308 if wg_chain_returns_value(m, sir_get(m, s, SIR_B)) == 1 { return 1 }
309 if wg_chain_returns_value(m, sir_get(m, s, SIR_C)) == 1 { return 1 }
310 }
311 if k == S_LOOP { if wg_chain_returns_value(m, sir_get(m, s, SIR_A)) == 1 { return 1 } }
312 s = sir_get(m, s, SIR_NEXT)
313 }
314 return 0
315}
316
317// S12c-5 (2026-09-05): 1 iff the chain (recursing into if/else and loop bodies) ASSIGNS an identifier named `name` --
318// the test that decides whether a fragment entry's declared output is carried as a WGSL local (see M_WGFRAGOUT).
319func wg_chain_assigns(m: *i64, head: i64, name: *u8) -> i64 {
320 var s: i64 = head
321 while s != 0 {
322 let k: i64 = sir_get(m, s, SIR_KIND)
323 if k == S_ASSIGN {
324 let l: i64 = sir_get(m, s, SIR_A)
325 if sir_get(m, l, SIR_KIND) == E_IDENT { if wg_name_is(m, l, name) == 1 { return 1 } }
326 }
327 if k == S_IF {
328 if wg_chain_assigns(m, sir_get(m, s, SIR_B), name) == 1 { return 1 }
329 if wg_chain_assigns(m, sir_get(m, s, SIR_C), name) == 1 { return 1 }
330 }
331 if k == S_LOOP { if wg_chain_assigns(m, sir_get(m, s, SIR_A), name) == 1 { return 1 } }
332 s = sir_get(m, s, SIR_NEXT)
333 }
334 return 0
335}
336// S12c-5: 1 iff the LAST top-level statement of the chain is a return (then no trailing `return fc;` is appended)
337func wg_chain_last_is_return(m: *i64, head: i64) -> i64 {
338 if head == 0 { return 0 }
339 var s: i64 = head
340 while sir_get(m, s, SIR_NEXT) != 0 { s = sir_get(m, s, SIR_NEXT) }
341 if sir_get(m, s, SIR_KIND) == S_RETURN { return 1 }
342 return 0
343}
344
345// ---- BINDING DERIVATION (S3) ----------------------------------------------------------------------
346// the binding a K_TEXTURE gets: WG_BIND_TEX_FIRST plus its ordinal among the K_TEXTURE declarations
347func wg_tex_binding(m: *i64, tex: i64) -> i64 {
348 var ord: i64 = 0
349 var d: i64 = m[M_DECLH]
350 while d != 0 {
351 if d == tex { return WG_BIND_TEX_FIRST + ord }
352 if sir_get(m, d, SIR_KIND) == K_TEXTURE { if sir_get(m, d, SIR_TY) == T_TEX2F { ord = ord + 2 } else { ord = ord + 1 } }
353 d = sir_get(m, d, SIR_NEXT)
354 }
355 return WG_BIND_TEX_FIRST + ord
356}
357// the K_STORAGE declared at this explicit binding, or 0
358func wg_storage_at(m: *i64, binding: i64) -> i64 {
359 var d: i64 = m[M_DECLH]
360 while d != 0 {
361 if sir_get(m, d, SIR_KIND) == K_STORAGE { if sir_get(m, d, SIR_A) == binding { return d } }
362 d = sir_get(m, d, SIR_NEXT)
363 }
364 return 0
365}
366
367// ---- GLSL backend ---------------------------------------------------------------------------
368func gl_expr(m: *i64, id: i64, out: *u8, pos: i64, cap: i64, trace: *i64, tcap: i64, tn: *i64) -> i64 {
369 if id == 0 { return pos }
370 var p: i64 = pos
371 let k: i64 = sir_get(m, id, SIR_KIND)
372 let ty: i64 = sir_get(m, id, SIR_TY)
373 tr_add(trace, tcap, tn, id)
374 if k == E_LIT {
375 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, id, SIR_NAME)))
376 // S12c-5 (2026-09-05): a literal built with sir_lit_u carries its `u` suffix in GLSL too -- the spelling a uint compare
377 // needs in GLSL ES 3.00 (`b!=0u`), and the spelling the hand cast fragment carries. A plain T_U32 literal stays bare
378 // here on purpose: the shipping fullscreen triangle's shift amount is bare in GLSL and suffixed only in WGSL.
379 if sir_get(m, id, SIR_A) == SIR_LIT_USUFFIX { p = eb_put(out, p, cap, "u" as *u8) }
380 return p
381 }
382 if k == E_IDENT {
383 // S4: a parameter bound to @builtin(position) has no name of its own in GLSL -- it IS gl_FragCoord.
384 // Every other identifier stays bare (GLSL uniforms are free-standing; see wg_expr for the WGSL twin).
385 let gp: i64 = wg_fn_param(m, m[M_CURFN], sir_cstr(m, sir_get(m, id, SIR_NAME)))
386 if gp != 0 { if sir_get(m, gp, SIR_A) == P_BUILTIN_POSITION { return eb_put(out, p, cap, "gl_FragCoord" as *u8) } }
387 return eb_put(out, p, cap, sir_cstr(m, sir_get(m, id, SIR_NAME)))
388 }
389 if k == E_BUILTIN {
390 let b: *u8 = sir_cstr(m, sir_get(m, id, SIR_NAME))
391 // GE43: WebGL2 has no compute stage, so it has no invocation id. Refuse by name -- an
392 // emitter that improvised gl_FragCoord here would compile and draw the wrong thing forever.
393 if b[0] == (103 as u8) { sir_refuse(m, "glsl: global_invocation_id -- GLSL ES 3.00 (WebGL2) has no compute stage; this kernel reaches a third-party browser only through the WGSL door (GE43)" as *u8); return p }
394 if b[0] == (118 as u8) { return eb_put(out, p, cap, "gl_VertexID" as *u8) }
395 // S12a (2026-09-05): the instance index needs no declaration in GLSL ES 3.00.
396 if b[0] == (105 as u8) { return eb_put(out, p, cap, "gl_InstanceID" as *u8) }
397 // S4: a declared position INPUT (sir_param_position, fragment stage) reads as gl_FragCoord; with no
398 // such parameter the builtin keeps its vertex-stage meaning, gl_Position (the output being assigned).
399 if wg_fn_position_param(m, m[M_CURFN]) != 0 { return eb_put(out, p, cap, "gl_FragCoord" as *u8) }
400 return eb_put(out, p, cap, "gl_Position" as *u8)
401 }
402 if k == E_ATOMIC { sir_refuse(m, "glsl: atomic read-modify-write -- GLSL ES 3.00 (WebGL2) has no atomics and no storage buffers; WGSL-door only (GE43)" as *u8); return p }
403 if k == E_CAST {
404 let tn2: *u8 = gl_ty(ty)
405 if (tn2 as i64) == 0 { sir_refuse(m, "glsl: cast to a type outside the covered subset" as *u8); return p }
406 p = eb_put(out, p, cap, tn2)
407 p = eb_put(out, p, cap, "(" as *u8)
408 p = gl_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
409 return eb_put(out, p, cap, ")" as *u8)
410 }
411 if k == E_BIN {
412 p = eb_put(out, p, cap, "(" as *u8)
413 p = gl_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
414 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, id, SIR_NAME)))
415 p = gl_expr(m, sir_get(m, id, SIR_B), out, p, cap, trace, tcap, tn)
416 return eb_put(out, p, cap, ")" as *u8)
417 }
418 if k == E_NOT {
419 // S12c-4 (2026-09-05): logical not, (!x) in both dialects. The bang is CONSTRUCTED (WG_C_BANG) because the nx_cc lexer
420 // refuses '!' inside a string literal; the shape mirrors E_NEG exactly.
421 p = eb_put(out, p, cap, "(" as *u8)
422 if p + 1 < cap { out[p] = WG_C_BANG as u8; p = p + 1 }
423 p = gl_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
424 return eb_put(out, p, cap, ")" as *u8)
425 }
426 if k == E_NEG {
427 // R-G0 (2026-09-04): unary negation, (-x) in both dialects; the parentheses keep `a- -b` unambiguous.
428 p = eb_put(out, p, cap, "(-" as *u8)
429 p = gl_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
430 return eb_put(out, p, cap, ")" as *u8)
431 }
432 if k == E_SELECT {
433 // R-A (2026-09-04): GLSL spells a select as the ternary. The IR's condition is a scalar bool by
434 // construction (no vector-bool type exists), so the ternary's scalar-condition rule always holds.
435 p = eb_put(out, p, cap, "(" as *u8)
436 p = gl_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
437 p = eb_put(out, p, cap, "?" as *u8)
438 p = gl_expr(m, sir_get(m, id, SIR_B), out, p, cap, trace, tcap, tn)
439 p = eb_put(out, p, cap, ":" as *u8)
440 p = gl_expr(m, sir_get(m, id, SIR_C), out, p, cap, trace, tcap, tn)
441 return eb_put(out, p, cap, ")" as *u8)
442 }
443 if k == E_SWZ {
444 p = gl_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
445 p = eb_put(out, p, cap, "." as *u8)
446 return eb_put(out, p, cap, sir_cstr(m, sir_get(m, id, SIR_NAME)))
447 }
448 if k == E_INDEX {
449 p = gl_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
450 p = eb_put(out, p, cap, "[" as *u8)
451 p = gl_expr(m, sir_get(m, id, SIR_B), out, p, cap, trace, tcap, tn)
452 return eb_put(out, p, cap, "]" as *u8)
453 }
454 if k == E_TEXLOAD {
455 p = eb_put(out, p, cap, "texelFetch(" as *u8)
456 p = gl_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
457 p = eb_put(out, p, cap, "," as *u8)
458 p = gl_expr(m, sir_get(m, id, SIR_B), out, p, cap, trace, tcap, tn)
459 p = eb_put(out, p, cap, "," as *u8)
460 p = gl_expr(m, sir_get(m, id, SIR_C), out, p, cap, trace, tcap, tn)
461 return eb_put(out, p, cap, ")" as *u8)
462 }
463 if k == E_TEXSAMPLE {
464 p = eb_put(out, p, cap, "texture(" as *u8)
465 p = gl_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
466 p = eb_put(out, p, cap, "," as *u8)
467 p = gl_expr(m, sir_get(m, id, SIR_B), out, p, cap, trace, tcap, tn)
468 return eb_put(out, p, cap, ")" as *u8)
469 }
470 if k == E_CALL {
471 // S9: the callee is re-spelled for GLSL through the ONE map (dpdx/dpdy/inverseSqrt); the trace keeps the IR name.
472 p = eb_put(out, p, cap, gl_call_name(sir_cstr(m, sir_get(m, id, SIR_NAME))))
473 p = eb_put(out, p, cap, "(" as *u8)
474 var a: i64 = sir_get(m, id, SIR_A)
475 var first: i64 = 1
476 while a != 0 {
477 if first == 0 { p = eb_put(out, p, cap, "," as *u8) }
478 first = 0
479 p = gl_expr(m, a, out, p, cap, trace, tcap, tn)
480 a = sir_get(m, a, SIR_NEXT)
481 }
482 return eb_put(out, p, cap, ")" as *u8)
483 }
484 if k == E_CTOR {
485 let tn3: *u8 = gl_ty(ty)
486 if (tn3 as i64) == 0 { sir_refuse(m, "glsl: constructor for a type outside the covered subset" as *u8); return p }
487 p = eb_put(out, p, cap, tn3)
488 p = eb_put(out, p, cap, "(" as *u8)
489 var a2: i64 = sir_get(m, id, SIR_A)
490 var f2: i64 = 1
491 while a2 != 0 {
492 if f2 == 0 { p = eb_put(out, p, cap, "," as *u8) }
493 f2 = 0
494 p = gl_expr(m, a2, out, p, cap, trace, tcap, tn)
495 a2 = sir_get(m, a2, SIR_NEXT)
496 }
497 return eb_put(out, p, cap, ")" as *u8)
498 }
499 sir_refuse(m, "glsl: expression kind outside the covered subset" as *u8)
500 return p
501}
502
503func gl_stmts(m: *i64, head: i64, out: *u8, pos: i64, cap: i64, trace: *i64, tcap: i64, tn: *i64) -> i64 {
504 var p: i64 = pos
505 var s: i64 = head
506 while s != 0 {
507 let k: i64 = sir_get(m, s, SIR_KIND)
508 tr_add(trace, tcap, tn, s)
509 if k == S_VAR {
510 // R-D (2026-09-04): a local may be struct-typed; gl_tyname spells a declared struct by name.
511 let t: *u8 = gl_tyname(m, sir_get(m, s, SIR_TY))
512 if (t as i64) == 0 { sir_refuse(m, "glsl: local of a type outside the covered subset" as *u8); return p }
513 // S12c-5 (2026-09-05): a constant local (sir_const, SIR_D=2) is `const T n=...;` -- the hand cast fragment's SHD_CTR.
514 if sir_get(m, s, SIR_D) == SIR_VAR_CONST { p = eb_put(out, p, cap, "const " as *u8) }
515 p = eb_put(out, p, cap, t)
516 p = eb_put(out, p, cap, " " as *u8)
517 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, s, SIR_NAME)))
518 // R-G0 (2026-09-04): a local declared WITHOUT an initialiser (init 0) is `float v;` -- the world shader
519 // declares `var col:vec3f;` and fills it per branch; an emitted `=` with nothing after it would not compile.
520 if sir_get(m, s, SIR_A) != 0 {
521 p = eb_put(out, p, cap, "=" as *u8)
522 p = gl_expr(m, sir_get(m, s, SIR_A), out, p, cap, trace, tcap, tn)
523 }
524 p = eb_put(out, p, cap, ";\n" as *u8)
525 }
526 if k == S_ASSIGN {
527 p = gl_expr(m, sir_get(m, s, SIR_A), out, p, cap, trace, tcap, tn)
528 p = eb_put(out, p, cap, "=" as *u8)
529 p = gl_expr(m, sir_get(m, s, SIR_B), out, p, cap, trace, tcap, tn)
530 p = eb_put(out, p, cap, ";\n" as *u8)
531 }
532 if k == S_RETURN {
533 // S5 (2026-09-04): GLSL ES 3.00 HAS NO VALUE-RETURNING ENTRY POINT. A fragment entry ASSIGNS
534 // its declared `out` variable; WGSL RETURNS one. One IR node, two shapes -- the same structural
535 // split the vertex stage already has (GLSL assigns gl_Position, WGSL returns it), and the exact
536 // pair this backend exists to own. M_FRAGOUT is non-zero ONLY inside the fragment entry's body,
537 // so an ordinary helper in the same module still emits a `return`.
538 if m[M_FRAGOUT] != 0 {
539 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, m[M_FRAGOUT], SIR_NAME)))
540 p = eb_put(out, p, cap, "=" as *u8)
541 p = gl_expr(m, sir_get(m, s, SIR_A), out, p, cap, trace, tcap, tn)
542 p = eb_put(out, p, cap, ";\n" as *u8)
543 } else {
544 // S12c-1 (2026-09-05): a VOID return is `return;` -- never `return ;` with a dangling expression slot.
545 if sir_get(m, s, SIR_A) == 0 { p = eb_put(out, p, cap, "return;\n" as *u8) } else {
546 p = eb_put(out, p, cap, "return " as *u8)
547 p = gl_expr(m, sir_get(m, s, SIR_A), out, p, cap, trace, tcap, tn)
548 p = eb_put(out, p, cap, ";\n" as *u8)
549 }
550 }
551 }
552 if k == S_DISCARD { p = eb_put(out, p, cap, "discard;\n" as *u8) }
553 if k == S_IF {
554 p = eb_put(out, p, cap, "if(" as *u8)
555 p = gl_expr(m, sir_get(m, s, SIR_A), out, p, cap, trace, tcap, tn)
556 p = eb_put(out, p, cap, "){\n" as *u8)
557 p = gl_stmts(m, sir_get(m, s, SIR_B), out, p, cap, trace, tcap, tn)
558 p = eb_put(out, p, cap, "}\n" as *u8)
559 if sir_get(m, s, SIR_C) != 0 {
560 p = eb_put(out, p, cap, "else{\n" as *u8)
561 p = gl_stmts(m, sir_get(m, s, SIR_C), out, p, cap, trace, tcap, tn)
562 p = eb_put(out, p, cap, "}\n" as *u8)
563 }
564 }
565 if k == S_LOOP {
566 p = eb_put(out, p, cap, "while(true){\n" as *u8)
567 p = gl_stmts(m, sir_get(m, s, SIR_A), out, p, cap, trace, tcap, tn)
568 p = eb_put(out, p, cap, "}\n" as *u8)
569 }
570 if k == S_BREAK { p = eb_put(out, p, cap, "break;\n" as *u8) }
571 if k == S_EXPR {
572 p = gl_expr(m, sir_get(m, s, SIR_A), out, p, cap, trace, tcap, tn)
573 p = eb_put(out, p, cap, ";\n" as *u8)
574 }
575 s = sir_get(m, s, SIR_NEXT)
576 }
577 return p
578}
579
580func glsl_emit_module(m: *i64, stage: i64, out: *u8, cap: i64, trace: *i64, tcap: i64, tn: *i64) -> i64 {
581 if m[M_CLIP_DEPTH] != SIR_CLIP_NATIVE && m[M_CLIP_DEPTH] != SIR_CLIP_NEGATIVE_ONE_TO_ONE { sir_refuse(m, "shader: unsupported source clip-depth convention" as *u8); return 0 - 1 }
582 var p: i64 = 0
583 // GE43: WebGL2 has no compute stage at all. Refuse the STAGE by name before emitting a byte, so a
584 // kernel can never be mis-shaped into a fragment program that compiles, links and draws nothing.
585 if stage == STAGE_COMPUTE { sir_refuse(m, "glsl: compute stage -- GLSL ES 3.00 (WebGL2) has no compute; a kernel reaches a third-party browser only through the WGSL door (GE43/GE44), NishiOS through the dxg lane" as *u8); return 0 - 1 }
586 p = eb_put(out, p, cap, "#version 300 es\n" as *u8)
587 if stage == STAGE_FRAGMENT { p = eb_put(out, p, cap, "precision highp float;precision highp int;\n" as *u8) }
588 var d: i64 = m[M_DECLH]
589 while d != 0 {
590 let k: i64 = sir_get(m, d, SIR_KIND)
591 tr_add(trace, tcap, tn, d)
592 // GE43: named refusal FIRST -- a u32 storage element has a GLSL type name, so without this
593 // the declaration would fall through every branch below and vanish SILENTLY from the output.
594 if k == K_STORAGE { sir_refuse(m, "glsl: storage buffer declaration -- GLSL ES 3.00 (WebGL2) has no SSBO; WGSL-door only (GE43)" as *u8); return 0 - 1 }
595 // R-D (2026-09-04): a struct declaration -- `struct Hit{vec3 pos;float d;};`. Members are the K_PARAM
596 // chain under SIR_A, each traced and spelled through gl_tyname (a struct-typed member resolves by name;
597 // an uncovered or texture-typed member refuses by name, never vanishes). Handled BEFORE the generic
598 // type check for the same reason K_TEXTURE is.
599 if k == K_STRUCT {
600 p = eb_put(out, p, cap, "struct " as *u8)
601 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
602 p = eb_put(out, p, cap, "{" as *u8)
603 var mb: i64 = sir_get(m, d, SIR_A)
604 while mb != 0 {
605 tr_add(trace, tcap, tn, mb)
606 if wg_is_texty(sir_get(m, mb, SIR_TY)) == 1 { sir_refuse(m, "glsl: texture-typed struct member -- a texture is a bound resource, never a value; refused in both dialects" as *u8); return 0 - 1 }
607 let mt: *u8 = gl_tyname(m, sir_get(m, mb, SIR_TY))
608 if (mt as i64) == 0 { sir_refuse(m, "glsl: struct member of a type outside the covered subset" as *u8); return 0 - 1 }
609 p = eb_put(out, p, cap, mt)
610 p = eb_put(out, p, cap, " " as *u8)
611 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, mb, SIR_NAME)))
612 p = eb_put(out, p, cap, ";" as *u8)
613 mb = sir_get(m, mb, SIR_NEXT)
614 }
615 p = eb_put(out, p, cap, "};\n" as *u8)
616 }
617 // S3 (2026-09-04): a texture is a sampler uniform in GLSL. Handled BEFORE the generic type check for
618 // the same reason K_STORAGE is: gl_ty names the type, so the declaration would otherwise fall through
619 // every branch below and vanish SILENTLY. Only the covered texture type is lowered.
620 if k == K_TEXTURE {
621 let gtk: i64 = sir_get(m, d, SIR_TY)
622 if gtk != T_TEX3U { if gtk != T_TEX2F { sir_refuse(m, "glsl: texture type outside the covered subset -- usampler3D (T_TEX3U, texelFetch) and sampler2D (T_TEX2F, texture()) are lowered; refused rather than guessed" as *u8); return 0 - 1 } }
623 p = eb_put(out, p, cap, "uniform " as *u8)
624 p = eb_put(out, p, cap, gl_ty(gtk))
625 p = eb_put(out, p, cap, " " as *u8)
626 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
627 p = eb_put(out, p, cap, ";\n" as *u8)
628 }
629 // S3: the deprecated form refuses here as well, so BOTH backends cover exactly the same declarations
630 // -- a source that emits in one dialect and refuses in the other is a fork wearing one name.
631 if k == K_UNIFORM { if wg_is_texty(sir_get(m, d, SIR_TY)) == 1 { sir_refuse(m, "glsl: texture-typed uniform -- a texture is its own declaration kind (sir_texture / K_TEXTURE); refused so both backends cover the same source" as *u8); return 0 - 1 } }
632 let t: *u8 = gl_ty(sir_get(m, d, SIR_TY))
633 if (t as i64) == 0 { sir_refuse(m, "glsl: declaration of a type outside the covered subset" as *u8); return 0 - 1 }
634 if k == K_PRIVATE {
635 // GE55: module-scope private state is a bare global in GLSL (`T name;` / `T name[N];`), emitted in
636 // declaration order. `t` is this declaration's GLSL type, already null-guarded above; the trace entry
637 // was added at the loop head like every other declaration. A texture-typed private refuses by name in
638 // BOTH backends, so the two cover exactly the same source.
639 if wg_is_texty(sir_get(m, d, SIR_TY)) == 1 { sir_refuse(m, "glsl: texture-typed private variable -- a texture is a bound resource, never module state; refused so both backends cover the same source" as *u8); return 0 - 1 }
640 p = eb_put(out, p, cap, t)
641 p = eb_put(out, p, cap, " " as *u8)
642 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
643 if sir_get(m, d, SIR_A) > 0 {
644 p = eb_put(out, p, cap, "[" as *u8)
645 p = eb_num(out, p, cap, sir_get(m, d, SIR_A))
646 p = eb_put(out, p, cap, "]" as *u8)
647 }
648 p = eb_put(out, p, cap, ";\n" as *u8)
649 }
650 if k == K_UNIFORM {
651 p = eb_put(out, p, cap, "uniform " as *u8)
652 p = eb_put(out, p, cap, t)
653 p = eb_put(out, p, cap, " " as *u8)
654 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
655 if sir_get(m, d, SIR_A) > 0 {
656 p = eb_put(out, p, cap, "[" as *u8)
657 p = eb_num(out, p, cap, sir_get(m, d, SIR_A))
658 p = eb_put(out, p, cap, "]" as *u8)
659 }
660 p = eb_put(out, p, cap, ";\n" as *u8)
661 }
662 if k == K_ATTRIB {
663 p = eb_put(out, p, cap, "layout(location=" as *u8)
664 p = eb_num(out, p, cap, sir_get(m, d, SIR_A))
665 p = eb_put(out, p, cap, ") in " as *u8)
666 p = eb_put(out, p, cap, t)
667 p = eb_put(out, p, cap, " " as *u8)
668 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
669 p = eb_put(out, p, cap, ";\n" as *u8)
670 }
671 // S5 (2026-09-04): THE FRAGMENT OUTPUT IS A DECLARATION IN GLSL. `layout(location=N)` is emitted
672 // only for N>0: location 0 is the default the shipping FSH spells as a bare `out vec4 fc;`, so the
673 // derived bytes reproduce the hand-written form exactly instead of merely being equivalent to it.
674 if k == K_FRAGOUT {
675 if stage != STAGE_FRAGMENT { sir_refuse(m, "glsl: fragment output declaration (K_FRAGOUT) outside a fragment stage -- only the fragment stage has a colour output; refused rather than declared where nothing can write it" as *u8); return 0 - 1 }
676 if wg_decl_kind_count(m, K_FRAGOUT) > 1 { sir_refuse(m, "glsl: more than one fragment output declared -- multiple render targets are their own rung; refused rather than emitting the first and silently dropping the rest" as *u8); return 0 - 1 }
677 if sir_get(m, d, SIR_A) > 0 {
678 p = eb_put(out, p, cap, "layout(location=" as *u8)
679 p = eb_num(out, p, cap, sir_get(m, d, SIR_A))
680 p = eb_put(out, p, cap, ") " as *u8)
681 }
682 p = eb_put(out, p, cap, "out " as *u8)
683 p = eb_put(out, p, cap, t)
684 p = eb_put(out, p, cap, " " as *u8)
685 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
686 p = eb_put(out, p, cap, ";\n" as *u8)
687 }
688 if k == K_VARY {
689 if sir_get(m, d, SIR_B) == 1 { p = eb_put(out, p, cap, "flat " as *u8) }
690 if stage == STAGE_VERTEX { p = eb_put(out, p, cap, "out " as *u8) } else { p = eb_put(out, p, cap, "in " as *u8) }
691 p = eb_put(out, p, cap, t)
692 p = eb_put(out, p, cap, " " as *u8)
693 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
694 p = eb_put(out, p, cap, ";\n" as *u8)
695 }
696 d = sir_get(m, d, SIR_NEXT)
697 }
698 var f: i64 = m[M_FUNCH]
699 while f != 0 {
700 tr_add(trace, tcap, tn, f)
701 m[M_CURFN] = f
702 if wg_fn_is_plain(m, f, stage) == 1 {
703 // R-E (2026-09-04): a function may RETURN a struct in GLSL ES 3.00 exactly as in WGSL, so the canonical
704 // shape is the struct return in both dialects and no out-parameter twin exists; gl_tyname spells it.
705 let rt: *u8 = gl_tyname(m, sir_get(m, f, SIR_TY))
706 if (rt as i64) == 0 { sir_refuse(m, "glsl: return type outside the covered subset" as *u8); return 0 - 1 }
707 p = eb_put(out, p, cap, rt)
708 p = eb_put(out, p, cap, " " as *u8)
709 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, f, SIR_NAME)))
710 p = eb_put(out, p, cap, "(" as *u8)
711 var pa: i64 = sir_get(m, f, SIR_A)
712 var pf: i64 = 1
713 while pa != 0 {
714 if pf == 0 { p = eb_put(out, p, cap, "," as *u8) }
715 pf = 0
716 tr_add(trace, tcap, tn, pa)
717 let pt: *u8 = gl_tyname(m, sir_get(m, pa, SIR_TY))
718 if (pt as i64) == 0 { sir_refuse(m, "glsl: parameter type outside the covered subset" as *u8); return 0 - 1 }
719 p = eb_put(out, p, cap, pt)
720 p = eb_put(out, p, cap, " " as *u8)
721 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, pa, SIR_NAME)))
722 pa = sir_get(m, pa, SIR_NEXT)
723 }
724 p = eb_put(out, p, cap, "){\n" as *u8)
725 } else {
726 // S4 (2026-09-04): GLSL main() takes no parameters. A parameter bound to @builtin(position) on a
727 // FRAGMENT entry is gl_FragCoord -- implicit, so nothing is emitted for it here and its reads spell
728 // it (gl_expr). Any other entry-point parameter is an input GLSL binds by module-scope declaration
729 // (K_ATTRIB / K_VARY), never by parameter: refused by name rather than dropped from the program.
730 var gp: i64 = sir_get(m, f, SIR_A)
731 while gp != 0 {
732 tr_add(trace, tcap, tn, gp)
733 if sir_get(m, gp, SIR_A) != P_BUILTIN_POSITION { sir_refuse(m, "glsl: entry-point parameter that is not the @builtin(position) input -- GLSL main() takes no parameters; inputs are module-scope declarations (K_ATTRIB / K_VARY); refused rather than silently dropped" as *u8); return 0 - 1 }
734 if stage != STAGE_FRAGMENT { sir_refuse(m, "glsl: @builtin(position) declared as an input outside a fragment stage -- position is a fragment-stage input (gl_FragCoord) and a vertex-stage output (gl_Position); refused rather than guessed" as *u8); return 0 - 1 }
735 gp = sir_get(m, gp, SIR_NEXT)
736 }
737 // S5: a fragment entry that RETURNS A VALUE must have somewhere to put it. Before S5 this emitted
738 // `void main(){ return vec4(...); }` -- a value returned from a void function, against no declared
739 // output -- invalid GLSL ES 3.00 on BOTH counts, shipped with no refusal, and invisible because
740 // nothing pinned the GLSL fragment bytes. A shader that only discards declares no output and is
741 // untouched by this rule.
742 if stage == STAGE_FRAGMENT { if wg_chain_returns_value(m, sir_get(m, f, SIR_B)) == 1 {
743 let fo: i64 = wg_fragout(m)
744 if fo == 0 { sir_refuse(m, "glsl: fragment entry returns a value with no declared fragment output -- GLSL ES 3.00 has no value-returning entry point; declare the output with sir_fragout (K_FRAGOUT) and the return lowers to an assignment" as *u8); return 0 - 1 }
745 m[M_FRAGOUT] = fo
746 } }
747 p = eb_put(out, p, cap, "void " as *u8)
748 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, f, SIR_NAME)))
749 p = eb_put(out, p, cap, "(){\n" as *u8)
750 }
751 p = gl_stmts(m, sir_get(m, f, SIR_B), out, p, cap, trace, tcap, tn)
752 // S5: the assignment shape belongs to the ENTRY body only -- clear it before the next function so a
753 // helper declared after the entry cannot inherit it and silently assign the colour output.
754 m[M_FRAGOUT] = 0
755 p = eb_put(out, p, cap, "}\n" as *u8)
756 f = sir_get(m, f, SIR_NEXT)
757 }
758 m[M_CURFN] = 0
759 if sir_refused(m) != 0 { return 0 - 1 }
760 if p + 1 < cap { out[p] = 0 as u8 }
761 return p
762}
763
764// ---- WGSL backend ----------------------------------------------------------------------------
765// R-G1 (2026-09-04): WHICH FUNCTION IS THE ENTRY. Until the world shader arrived every staged module held ONE
766// function, so the backends treated every function of a vertex/fragment/compute module as the entry and refused
767// helpers by name ("entry-point parameter that is not the @builtin(position) input"). The rule, ONE for both
768// dialects: in a staged module the function named `main` is the entry (GLSL requires that name; the WGSL entry
769// keeps it and the page names its entryPoint); every other function is a plain function in any stage.
770func wg_fn_is_plain(m: *i64, f: i64, stage: i64) -> i64 {
771 if stage == STAGE_PLAIN { return 1 }
772 if wg_name_is(m, f, "main" as *u8) == 1 { return 0 }
773 return 1
774}
775// R-A TRACE IDENTITY (2026-09-04): reverse out[a..b) in place. The E_SELECT arm emits its three operands in IR
776// order (the trace nx_wgsl_gate compares across dialects) and then rotates the spans into WGSL argument order
777// with three reversals -- no scratch buffer, no second visitation order, nothing to size.
778func wg_rev(out: *u8, a: i64, b: i64) -> i64 {
779 var i: i64 = a
780 var j: i64 = b - 1
781 while i < j {
782 let t: i64 = out[i] as i64
783 out[i] = out[j]
784 out[j] = t as u8
785 i = i + 1
786 j = j - 1
787 }
788 return 0
789}
790
791// S12c-6 (2026-09-05): WGSL's clamp/min/max/smoothstep/step take ONE type T for every argument (f32 or vecNf) -- there
792// is no scalar-bound overload -- while GLSL ES accepts clamp(vec3,float,float), and the hand cast fragment uses exactly
793// that form (the skin tail: clamp((vec3(ndl)+w3)/(1.+w3),0.,1.)). When any argument of one of these callees is a float
794// vector, every f32 argument is SPLATTED as vecNf(<arg>) in the WGSL dialect only; the GLSL emitter is a different
795// backend and never sees this, so the token ruler's IDENTICAL cannot move. A user function or a builtin with all-scalar
796// arguments (max(0.,-n.y), clamp(fl9,0.,.3)) passes through untouched -- the neg-control in nx_wgsl_gate pins that.
797func wg_splat_callee(n: *u8) -> i64 {
798 if wg_streq(n, "clamp" as *u8) == 1 { return 1 }
799 if wg_streq(n, "min" as *u8) == 1 { return 1 }
800 if wg_streq(n, "max" as *u8) == 1 { return 1 }
801 if wg_streq(n, "smoothstep" as *u8) == 1 { return 1 }
802 if wg_streq(n, "step" as *u8) == 1 { return 1 }
803 return 0
804}
805// the float-vector type among a call's arguments (the type every f32 argument must be splatted to), 0 when none
806func wg_vec_arg_ty(m: *i64, id: i64) -> i64 {
807 var a: i64 = sir_get(m, id, SIR_A)
808 while a != 0 {
809 let t: i64 = sir_get(m, a, SIR_TY)
810 if t == T_V2F { return t }
811 if t == T_V3F { return t }
812 if t == T_V4F { return t }
813 a = sir_get(m, a, SIR_NEXT)
814 }
815 return 0
816}
817
818func wg_expr(m: *i64, id: i64, out: *u8, pos: i64, cap: i64, trace: *i64, tcap: i64, tn: *i64) -> i64 {
819 if id == 0 { return pos }
820 var p: i64 = pos
821 let k: i64 = sir_get(m, id, SIR_KIND)
822 let ty: i64 = sir_get(m, id, SIR_TY)
823 tr_add(trace, tcap, tn, id)
824 if k == E_LIT {
825 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, id, SIR_NAME)))
826 // WGSL DIALECT RULE: an unsigned literal carries its u suffix. A shift amount MUST be u32
827 // in WGSL and must NOT be in GLSL -- the backend owns that, the author never sees it.
828 if ty == T_U32 { p = eb_put(out, p, cap, "u" as *u8) }
829 return p
830 }
831 if k == E_IDENT {
832 // S2: a uniform lives in struct U behind binding 0, so its read is `u.<name>`; a parameter or a
833 // local of the current function keeps the bare name (it shadows the uniform, as in the language).
834 // GLSL keeps every identifier bare -- its uniforms are free-standing -- so only THIS backend qualifies.
835 if wg_resolves_to_uniform(m, sir_cstr(m, sir_get(m, id, SIR_NAME))) == 1 { p = eb_put(out, p, cap, "u." as *u8) }
836 // S7 (2026-09-05): a varying lives in the interstage struct -- written as vo.<name> in the vertex entry,
837 // read as vin.<name> in the fragment entry (M_VIOMODE 1 / 2). Outside an entry (a plain helper) the
838 // struct is not in scope, so the reference refuses by name rather than emitting a bare undeclared
839 // identifier. GLSL keeps every varying bare -- its varyings are module-scope -- so only THIS backend qualifies.
840 if wg_resolves_to_varying(m, sir_cstr(m, sir_get(m, id, SIR_NAME))) == 1 {
841 if m[M_VIOMODE] == 1 { p = eb_put(out, p, cap, "vo." as *u8) }
842 if m[M_VIOMODE] == 2 { p = eb_put(out, p, cap, "vin." as *u8) }
843 if m[M_VIOMODE] == 0 { sir_refuse(m, "wgsl: varying referenced outside a vertex or fragment entry -- the interstage struct is an entry parameter/return, not module scope; pass the value to the helper explicitly" as *u8); return p }
844 }
845 return eb_put(out, p, cap, sir_cstr(m, sir_get(m, id, SIR_NAME)))
846 }
847 if k == E_BUILTIN {
848 let b: *u8 = sir_cstr(m, sir_get(m, id, SIR_NAME))
849 // vertex_index arrives as u32; the IR types the expression i32, so the backend converts.
850 if b[0] == (118 as u8) { return eb_put(out, p, cap, "i32(vi)" as *u8) }
851 // S12a (2026-09-05): instance_index arrives as u32 like vertex_index and is typed i32 by the IR; the entry binds
852 // it as `ii` only when the module uses it (M_USESII), so unrelated modules stay byte-identical.
853 if b[0] == (105 as u8) { return eb_put(out, p, cap, "i32(iidx)" as *u8) }
854 // GE43: the compute entry binds @builtin(global_invocation_id) to the parameter `gid`.
855 if b[0] == (103 as u8) { return eb_put(out, p, cap, "gid" as *u8) }
856 // S4 (2026-09-04): a READ of @builtin(position) resolves to the entry parameter the function declared
857 // for it (sir_param_position); with no such parameter it is an UNDECLARED INPUT and refuses by name.
858 // Before S4 this emitted the placeholder identifier POSITION with no refusal. (An ASSIGNMENT to the
859 // builtin never reaches here -- wg_stmts turns it into the vertex stage's return.)
860 // S7 (2026-09-05): inside a fragment entry that takes the interstage struct (M_VIOMODE=2) the position
861 // arrives as vin.bpos -- the declared parameter (if any) was folded into it by the entry emitter.
862 if m[M_VIOMODE] == 2 { return eb_put(out, p, cap, "vin.bpos" as *u8) }
863 let pp: i64 = wg_fn_position_param(m, m[M_CURFN])
864 if pp == 0 { sir_refuse(m, "wgsl: @builtin(position) read without a declared entry parameter -- declare it with sir_param_position; an undeclared input is refused rather than emitted as a placeholder identifier" as *u8); return p }
865 return eb_put(out, p, cap, sir_cstr(m, sir_get(m, pp, SIR_NAME)))
866 }
867 if k == E_ATOMIC {
868 // WGSL DIALECT RULE: an atomic builtin takes a POINTER to its target -- the `&` is the
869 // backend's, never the author's. The op spelling is the IR's (atomicMin/atomicMax/atomicAdd).
870 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, id, SIR_NAME)))
871 p = eb_put(out, p, cap, "(&" as *u8)
872 p = wg_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
873 p = eb_put(out, p, cap, "," as *u8)
874 p = wg_expr(m, sir_get(m, id, SIR_B), out, p, cap, trace, tcap, tn)
875 return eb_put(out, p, cap, ")" as *u8)
876 }
877 if k == E_CAST {
878 let tn2: *u8 = wg_ty(ty)
879 if (tn2 as i64) == 0 { sir_refuse(m, "wgsl: cast to a type outside the covered subset" as *u8); return p }
880 p = eb_put(out, p, cap, tn2)
881 p = eb_put(out, p, cap, "(" as *u8)
882 p = wg_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
883 return eb_put(out, p, cap, ")" as *u8)
884 }
885 if k == E_BIN {
886 p = eb_put(out, p, cap, "(" as *u8)
887 p = wg_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
888 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, id, SIR_NAME)))
889 p = wg_expr(m, sir_get(m, id, SIR_B), out, p, cap, trace, tcap, tn)
890 return eb_put(out, p, cap, ")" as *u8)
891 }
892 if k == E_NOT {
893 // S12c-4 (2026-09-05): logical not, (!x) -- the WGSL twin of the GLSL arm, bang constructed (WG_C_BANG).
894 p = eb_put(out, p, cap, "(" as *u8)
895 if p + 1 < cap { out[p] = WG_C_BANG as u8; p = p + 1 }
896 p = wg_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
897 return eb_put(out, p, cap, ")" as *u8)
898 }
899 if k == E_NEG {
900 // R-G0 (2026-09-04): unary negation, (-x) in both dialects (see the GLSL twin).
901 p = eb_put(out, p, cap, "(-" as *u8)
902 p = wg_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
903 return eb_put(out, p, cap, ")" as *u8)
904 }
905 if k == E_SELECT {
906 // R-A (2026-09-04): WGSL DIALECT RULE -- select(f, t, cond) takes the FALSE value FIRST. The IR carries
907 // (cond, then, else); the reordering is the backend's, the author never writes it.
908 // TRACE IDENTITY (same day, caught by nx_wgsl_gate's selectlet_trace_equal tooth): the operands are VISITED
909 // in IR order (A, B, C) exactly as gl_expr visits them, so the node trace is dialect-independent; the WGSL
910 // argument order is produced afterwards by an in-place rotation (reverse the span, reverse each operand
911 // back) and only when every separator landed inside cap -- a truncated span is left as emitted.
912 p = eb_put(out, p, cap, "select(" as *u8)
913 let s0: i64 = p
914 p = wg_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
915 let la: i64 = p - s0
916 p = eb_put(out, p, cap, "," as *u8)
917 let s1: i64 = p
918 p = wg_expr(m, sir_get(m, id, SIR_B), out, p, cap, trace, tcap, tn)
919 let lb: i64 = p - s1
920 p = eb_put(out, p, cap, "," as *u8)
921 let s2: i64 = p
922 p = wg_expr(m, sir_get(m, id, SIR_C), out, p, cap, trace, tcap, tn)
923 let lc: i64 = p - s2
924 if p - s0 == la + lb + lc + 2 {
925 wg_rev(out, s0, p)
926 wg_rev(out, s0, s0 + lc)
927 wg_rev(out, s0 + lc + 1, s0 + lc + 1 + lb)
928 wg_rev(out, s0 + lc + 1 + lb + 1, p)
929 }
930 return eb_put(out, p, cap, ")" as *u8)
931 }
932 if k == E_SWZ {
933 p = wg_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
934 p = eb_put(out, p, cap, "." as *u8)
935 return eb_put(out, p, cap, sir_cstr(m, sir_get(m, id, SIR_NAME)))
936 }
937 if k == E_INDEX {
938 // S12c-2b: a float[N] uniform is carried as array<vec4f,ceil(N/4)> in struct U, so its read is u.name[i/4][i%4] --
939 // the ONE rule the struct emitter and the layout ruler apply (wg_f32arr_len). The index expression is emitted TWICE
940 // here (once per bracket), so the WGSL trace visits its nodes twice: the trace oracle is DECLARED inapplicable to
941 // modules that read a float[N] uniform (the cast is one), and `cast_trace_equal` is printed, never asserted, for them.
942 let bx: i64 = sir_get(m, id, SIR_A)
943 if sir_get(m, bx, SIR_KIND) == E_IDENT { if wg_f32arr_len(m, sir_cstr(m, sir_get(m, bx, SIR_NAME))) > 0 {
944 p = wg_expr(m, bx, out, p, cap, trace, tcap, tn)
945 p = eb_put(out, p, cap, "[(" as *u8)
946 p = wg_expr(m, sir_get(m, id, SIR_B), out, p, cap, trace, tcap, tn)
947 p = eb_put(out, p, cap, ")/" as *u8)
948 p = eb_num(out, p, cap, WG_F32ARR_LANES)
949 p = eb_put(out, p, cap, "][(" as *u8)
950 p = wg_expr(m, sir_get(m, id, SIR_B), out, p, cap, trace, tcap, tn)
951 p = eb_put(out, p, cap, ")%" as *u8)
952 p = eb_num(out, p, cap, WG_F32ARR_LANES)
953 return eb_put(out, p, cap, "]" as *u8)
954 } }
955 p = wg_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
956 p = eb_put(out, p, cap, "[" as *u8)
957 p = wg_expr(m, sir_get(m, id, SIR_B), out, p, cap, trace, tcap, tn)
958 return eb_put(out, p, cap, "]" as *u8)
959 }
960 if k == E_TEXLOAD {
961 p = eb_put(out, p, cap, "textureLoad(" as *u8)
962 p = wg_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
963 p = eb_put(out, p, cap, "," as *u8)
964 p = wg_expr(m, sir_get(m, id, SIR_B), out, p, cap, trace, tcap, tn)
965 p = eb_put(out, p, cap, "," as *u8)
966 p = wg_expr(m, sir_get(m, id, SIR_C), out, p, cap, trace, tcap, tn)
967 return eb_put(out, p, cap, ")" as *u8)
968 }
969 if k == E_TEXSAMPLE {
970 // S5 (2026-09-04): THIS EMITTED `textureSample(t,samp,c)` AGAINST AN UNDECLARED `samp` -- WGSL that
971 // does not compile, produced with NO refusal, while the DECLARATION pass in wgsl_emit_module already
972 // refused a sampled texture_2d<f32> for precisely the sampler binding this backend does not declare.
973 // The declaration side refused and the expression side guessed: half a law, and the half left undone
974 // was the half that ships. MEASURED on the shipping world shader before choosing between building a
975 // sampler kind and refusing: texelFetch 1 / textureLoad 1 / texture( 0 / textureSample 0 over both
976 // whole files -- it performs ZERO sampled reads, because a texture_3d<u32> is read with textureLoad
977 // and textureLoad takes NO sampler. A sampler declaration kind would therefore be built for no
978 // measured caller. When a sampled read IS needed, the rung is a sampler declaration + its binding,
979 // and this refusal is the contract that will name it.
980 // GE54 (2026-09-05): textureSample(<tex>, <tex>_s, <coord>) -- the companion sampler declared beside
981 // the texture_2d<f32> binding. The texture node (SIR_A) is an identifier; its name plus `_s` is the
982 // sampler, so the two agree by construction. GLSL emits texture(<tex>, <coord>) -- one combined sampler2D.
983 p = eb_put(out, p, cap, "textureSample(" as *u8)
984 p = wg_expr(m, sir_get(m, id, SIR_A), out, p, cap, trace, tcap, tn)
985 p = eb_put(out, p, cap, "," as *u8)
986 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, sir_get(m, id, SIR_A), SIR_NAME)))
987 p = eb_put(out, p, cap, "_s," as *u8)
988 p = wg_expr(m, sir_get(m, id, SIR_B), out, p, cap, trace, tcap, tn)
989 return eb_put(out, p, cap, ")" as *u8)
990 }
991 if k == E_CALL {
992 let cn: *u8 = sir_cstr(m, sir_get(m, id, SIR_NAME))
993 p = eb_put(out, p, cap, cn)
994 p = eb_put(out, p, cap, "(" as *u8)
995 // S12c-6: every f32 argument of clamp/min/max/smoothstep/step is splatted to the call's float-vector type
996 // (wg_splat_callee / wg_vec_arg_ty above): WGSL has no scalar-bound overload, GLSL ES does, ONE source serves both.
997 var splat: i64 = 0
998 if wg_splat_callee(cn) == 1 { splat = wg_vec_arg_ty(m, id) }
999 var a: i64 = sir_get(m, id, SIR_A)
1000 var first: i64 = 1
1001 while a != 0 {
1002 if first == 0 { p = eb_put(out, p, cap, "," as *u8) }
1003 first = 0
1004 var wrap: i64 = 0
1005 if splat != 0 { if sir_get(m, a, SIR_TY) == T_F32 { wrap = 1 } }
1006 if wrap == 1 { p = eb_put(out, p, cap, wg_ty(splat)); p = eb_put(out, p, cap, "(" as *u8) }
1007 p = wg_expr(m, a, out, p, cap, trace, tcap, tn)
1008 if wrap == 1 { p = eb_put(out, p, cap, ")" as *u8) }
1009 a = sir_get(m, a, SIR_NEXT)
1010 }
1011 return eb_put(out, p, cap, ")" as *u8)
1012 }
1013 if k == E_CTOR {
1014 let tn3: *u8 = wg_ty(ty)
1015 if (tn3 as i64) == 0 { sir_refuse(m, "wgsl: constructor for a type outside the covered subset" as *u8); return p }
1016 p = eb_put(out, p, cap, tn3)
1017 p = eb_put(out, p, cap, "(" as *u8)
1018 var a2: i64 = sir_get(m, id, SIR_A)
1019 var f2: i64 = 1
1020 while a2 != 0 {
1021 if f2 == 0 { p = eb_put(out, p, cap, "," as *u8) }
1022 f2 = 0
1023 p = wg_expr(m, a2, out, p, cap, trace, tcap, tn)
1024 a2 = sir_get(m, a2, SIR_NEXT)
1025 }
1026 return eb_put(out, p, cap, ")" as *u8)
1027 }
1028 sir_refuse(m, "wgsl: expression kind outside the covered subset" as *u8)
1029 return p
1030}
1031
1032func wg_is_position(m: *i64, id: i64) -> i64 {
1033 if id == 0 { return 0 }
1034 if sir_get(m, id, SIR_KIND) != E_BUILTIN { return 0 }
1035 let b: *u8 = sir_cstr(m, sir_get(m, id, SIR_NAME))
1036 if b[0] == (112 as u8) { return 1 }
1037 return 0
1038}
1039
1040func wg_stmts(m: *i64, head: i64, out: *u8, pos: i64, cap: i64, trace: *i64, tcap: i64, tn: *i64) -> i64 {
1041 var p: i64 = pos
1042 var s: i64 = head
1043 while s != 0 {
1044 let k: i64 = sir_get(m, s, SIR_KIND)
1045 tr_add(trace, tcap, tn, s)
1046 if k == S_VAR {
1047 // R-D (2026-09-04): a local may be struct-typed; wg_tyname spells a declared struct by name.
1048 let t: *u8 = wg_tyname(m, sir_get(m, s, SIR_TY))
1049 if (t as i64) == 0 { sir_refuse(m, "wgsl: local of a type outside the covered subset" as *u8); return p }
1050 // R-C (2026-09-04): an immutable local (sir_let, SIR_D=1) is `let` in WGSL; the mutable one stays `var`.
1051 // S12c-5 (2026-09-05): a constant local (sir_const, SIR_D=2) is `const n:T=...;` (see the GLSL twin).
1052 if sir_get(m, s, SIR_D) == SIR_VAR_CONST { p = eb_put(out, p, cap, "const " as *u8) } else {
1053 if sir_get(m, s, SIR_D) == SIR_VAR_LET { p = eb_put(out, p, cap, "let " as *u8) } else { p = eb_put(out, p, cap, "var " as *u8) }
1054 }
1055 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, s, SIR_NAME)))
1056 p = eb_put(out, p, cap, ":" as *u8)
1057 p = eb_put(out, p, cap, t)
1058 // R-G0 (2026-09-04): a local declared WITHOUT an initialiser (init 0) is `var v:f32;` (see the GLSL twin).
1059 if sir_get(m, s, SIR_A) != 0 {
1060 p = eb_put(out, p, cap, "=" as *u8)
1061 p = wg_expr(m, sir_get(m, s, SIR_A), out, p, cap, trace, tcap, tn)
1062 }
1063 p = eb_put(out, p, cap, ";\n" as *u8)
1064 }
1065 if k == S_ASSIGN {
1066 // STRUCTURAL DIALECT DIFFERENCE, OWNED BY THE BACKEND: GLSL ASSIGNS gl_Position;
1067 // a WGSL vertex entry point RETURNS @builtin(position). One IR node, two shapes.
1068 if wg_is_position(m, sir_get(m, s, SIR_A)) == 1 {
1069 tr_add(trace, tcap, tn, sir_get(m, s, SIR_A))
1070 // S7 (2026-09-05): inside a vertex entry that returns the interstage struct (M_VIOMODE=1) the
1071 // position lands in vo.bpos and the entry returns vo after its body; with no varyings it is
1072 // the return itself, exactly as before -- one IR node, the same two shapes, plus the struct.
1073 let remap_depth: i64 = m[M_CLIP_DEPTH] == SIR_CLIP_NEGATIVE_ONE_TO_ONE
1074 if m[M_VIOMODE] == 1 { p = eb_put(out, p, cap, "vo.bpos=" as *u8) } else {
1075 if remap_depth { p = eb_put(out, p, cap, "{let nishiClipPosition=" as *u8) } else { p = eb_put(out, p, cap, "return " as *u8) }
1076 }
1077 p = wg_expr(m, sir_get(m, s, SIR_B), out, p, cap, trace, tcap, tn)
1078 p = eb_put(out, p, cap, ";\n" as *u8)
1079 if remap_depth {
1080 if m[M_VIOMODE] == 1 {
1081 p = eb_put(out, p, cap, "vo.bpos.z=(vo.bpos.z+vo.bpos.w)*0.5;\n" as *u8)
1082 } else {
1083 p = eb_put(out, p, cap, "return vec4f(nishiClipPosition.xy,(nishiClipPosition.z+nishiClipPosition.w)*0.5,nishiClipPosition.w);}\n" as *u8)
1084 }
1085 }
1086 } else {
1087 p = wg_expr(m, sir_get(m, s, SIR_A), out, p, cap, trace, tcap, tn)
1088 p = eb_put(out, p, cap, "=" as *u8)
1089 p = wg_expr(m, sir_get(m, s, SIR_B), out, p, cap, trace, tcap, tn)
1090 p = eb_put(out, p, cap, ";\n" as *u8)
1091 }
1092 }
1093 if k == S_RETURN {
1094 // S12c-1 (2026-09-05): a VOID return (no expression) inside the interstage-struct vertex entry (M_VIOMODE=1)
1095 // hands back the struct built so far -- `return vo;` -- the early exit the cast vertex shader uses to cull a
1096 // hair lock after writing its outputs. Anywhere else a void return is `return;`. GLSL says `return;` in both.
1097 if sir_get(m, s, SIR_A) == 0 {
1098 // S12c-5 (2026-09-05): inside a fragment entry whose body ASSIGNS the declared output (M_WGFRAGOUT), a void
1099 // return hands back that variable -- `return fc;` -- the WGSL spelling of the hand's `fc=...;return;` early exits.
1100 if m[M_VIOMODE] == 1 { p = eb_put(out, p, cap, "return vo;\n" as *u8) } else {
1101 if m[M_WGFRAGOUT] != 0 {
1102 p = eb_put(out, p, cap, "return " as *u8)
1103 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, m[M_WGFRAGOUT], SIR_NAME)))
1104 p = eb_put(out, p, cap, ";\n" as *u8)
1105 } else { p = eb_put(out, p, cap, "return;\n" as *u8) }
1106 }
1107 } else {
1108 p = eb_put(out, p, cap, "return " as *u8)
1109 p = wg_expr(m, sir_get(m, s, SIR_A), out, p, cap, trace, tcap, tn)
1110 p = eb_put(out, p, cap, ";\n" as *u8)
1111 }
1112 }
1113 if k == S_DISCARD { p = eb_put(out, p, cap, "discard;\n" as *u8) }
1114 if k == S_IF {
1115 p = eb_put(out, p, cap, "if(" as *u8)
1116 p = wg_expr(m, sir_get(m, s, SIR_A), out, p, cap, trace, tcap, tn)
1117 p = eb_put(out, p, cap, "){\n" as *u8)
1118 p = wg_stmts(m, sir_get(m, s, SIR_B), out, p, cap, trace, tcap, tn)
1119 p = eb_put(out, p, cap, "}\n" as *u8)
1120 if sir_get(m, s, SIR_C) != 0 {
1121 p = eb_put(out, p, cap, "else{\n" as *u8)
1122 p = wg_stmts(m, sir_get(m, s, SIR_C), out, p, cap, trace, tcap, tn)
1123 p = eb_put(out, p, cap, "}\n" as *u8)
1124 }
1125 }
1126 if k == S_LOOP {
1127 p = eb_put(out, p, cap, "loop{\n" as *u8)
1128 p = wg_stmts(m, sir_get(m, s, SIR_A), out, p, cap, trace, tcap, tn)
1129 p = eb_put(out, p, cap, "}\n" as *u8)
1130 }
1131 if k == S_BREAK { p = eb_put(out, p, cap, "break;\n" as *u8) }
1132 if k == S_EXPR {
1133 p = wg_expr(m, sir_get(m, s, SIR_A), out, p, cap, trace, tcap, tn)
1134 p = eb_put(out, p, cap, ";\n" as *u8)
1135 }
1136 s = sir_get(m, s, SIR_NEXT)
1137 }
1138 return p
1139}
1140
1141// GE43 CONTRACT SYMBOL: the compute entry point. WGSL spells the dispatch geometry on the entry
1142// (@workgroup_size) and hands each invocation its global id as a builtin bound to `gid`, which is
1143// what wg_expr emits for the global_invocation_id builtin -- one name, owned in two places on
1144// purpose so a rename here breaks the gate rather than the kernel.
1145func wgsl_compute_stage(m: *i64, f: i64, out: *u8, pos: i64, cap: i64) -> i64 {
1146 var p: i64 = pos
1147 p = eb_put(out, p, cap, "@compute @workgroup_size(" as *u8)
1148 p = eb_num(out, p, cap, WG_WORKGROUP)
1149 p = eb_put(out, p, cap, ") fn " as *u8)
1150 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, f, SIR_NAME)))
1151 p = eb_put(out, p, cap, "(@builtin(global_invocation_id) gid:vec3u){\n" as *u8)
1152 return p
1153}
1154
1155// THE CONTRACT SYMBOL. Returns bytes written, or -1 with the refusal named in the module.
1156func wgsl_emit_module(m: *i64, stage: i64, out: *u8, cap: i64, trace: *i64, tcap: i64, tn: *i64) -> i64 {
1157 if m[M_CLIP_DEPTH] != SIR_CLIP_NATIVE && m[M_CLIP_DEPTH] != SIR_CLIP_NEGATIVE_ONE_TO_ONE { sir_refuse(m, "shader: unsupported source clip-depth convention" as *u8); return 0 - 1 }
1158 var p: i64 = 0
1159 var d: i64 = m[M_DECLH]
1160 var nu: i64 = 0
1161 while d != 0 {
1162 if sir_get(m, d, SIR_KIND) == K_UNIFORM { nu = nu + 1 }
1163 d = sir_get(m, d, SIR_NEXT)
1164 }
1165 // uniforms become ONE uniform struct + binding -- WGSL has no free-standing uniforms.
1166 if nu > 0 {
1167 p = eb_put(out, p, cap, "struct U{\n" as *u8)
1168 d = m[M_DECLH]
1169 while d != 0 {
1170 if sir_get(m, d, SIR_KIND) == K_UNIFORM {
1171 tr_add(trace, tcap, tn, d)
1172 // S1 (2026-09-04): A TEXTURE IS A BOUND RESOURCE, NEVER A STRUCT MEMBER. wg_ty returns a
1173 // non-null name for a texture type, so before this guard a texture-typed K_UNIFORM passed
1174 // the type check and was emitted INSIDE struct U -- WGSL that does not compile, produced
1175 // with no refusal. The remedy is the dedicated kind (sir_texture / K_TEXTURE).
1176 if wg_is_texty(sir_get(m, d, SIR_TY)) == 1 { sir_refuse(m, "wgsl: texture-typed uniform -- a texture is a bound resource, never a struct U member; declare it with sir_texture (K_TEXTURE), refused rather than emitted inside struct U" as *u8); return 0 - 1 }
1177 let t: *u8 = wg_ty(sir_get(m, d, SIR_TY))
1178 if (t as i64) == 0 { sir_refuse(m, "wgsl: uniform of a type outside the covered subset" as *u8); return 0 - 1 }
1179 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
1180 p = eb_put(out, p, cap, ":" as *u8)
1181 if sir_get(m, d, SIR_A) > 0 {
1182 // S12c-2b: float[N] lowers to array<vec4f,ceil(N/4)> (wg_f32arr_vec4n -- the same rule the layout ruler
1183 // and the E_INDEX arm apply); every other element type keeps its own spelling.
1184 if sir_get(m, d, SIR_TY) == T_F32 {
1185 p = eb_put(out, p, cap, "array<" as *u8)
1186 p = eb_put(out, p, cap, wg_ty(T_V4F))
1187 p = eb_put(out, p, cap, "," as *u8)
1188 p = eb_num(out, p, cap, wg_f32arr_vec4n(sir_get(m, d, SIR_A)))
1189 p = eb_put(out, p, cap, ">" as *u8)
1190 } else {
1191 p = eb_put(out, p, cap, "array<" as *u8)
1192 p = eb_put(out, p, cap, t)
1193 p = eb_put(out, p, cap, "," as *u8)
1194 p = eb_num(out, p, cap, sir_get(m, d, SIR_A))
1195 p = eb_put(out, p, cap, ">" as *u8)
1196 }
1197 } else { p = eb_put(out, p, cap, t) }
1198 p = eb_put(out, p, cap, ",\n" as *u8)
1199 }
1200 d = sir_get(m, d, SIR_NEXT)
1201 }
1202 p = eb_put(out, p, cap, "}\n@group(" as *u8)
1203 p = eb_num(out, p, cap, wg_group(m))
1204 p = eb_put(out, p, cap, ")@binding(" as *u8)
1205 p = eb_num(out, p, cap, WG_BIND_UNIFORM)
1206 p = eb_put(out, p, cap, ")var<uniform> u:U;\n" as *u8)
1207 }
1208 d = m[M_DECLH]
1209 while d != 0 {
1210 let k: i64 = sir_get(m, d, SIR_KIND)
1211 if k == K_PRIVATE {
1212 // GE55: module-scope private state -- `var<private> name:T;` -- emitted in declaration order beside the
1213 // other module declarations, never inside struct U (so the layout never sees it) and never qualified
1214 // (wg_resolves_to_uniform matches K_UNIFORM only, so every read and write of it stays bare).
1215 tr_add(trace, tcap, tn, d)
1216 if wg_is_texty(sir_get(m, d, SIR_TY)) == 1 { sir_refuse(m, "wgsl: texture-typed private variable -- a texture is a bound resource, never module state; refused so both backends cover the same source" as *u8); return 0 - 1 }
1217 let tp: *u8 = wg_ty(sir_get(m, d, SIR_TY))
1218 if (tp as i64) == 0 { sir_refuse(m, "wgsl: private variable of a type outside the covered subset" as *u8); return 0 - 1 }
1219 p = eb_put(out, p, cap, "var<private> " as *u8)
1220 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
1221 p = eb_put(out, p, cap, ":" as *u8)
1222 if sir_get(m, d, SIR_A) > 0 {
1223 p = eb_put(out, p, cap, "array<" as *u8)
1224 p = eb_put(out, p, cap, tp)
1225 p = eb_put(out, p, cap, "," as *u8)
1226 p = eb_num(out, p, cap, sir_get(m, d, SIR_A))
1227 p = eb_put(out, p, cap, ">" as *u8)
1228 } else { p = eb_put(out, p, cap, tp) }
1229 p = eb_put(out, p, cap, ";\n" as *u8)
1230 }
1231 if k == K_VARY {
1232 tr_add(trace, tcap, tn, d)
1233 // S7 (2026-09-05): varyings are ONE interstage struct in WGSL -- struct VIO{@builtin(position)
1234 // bpos:vec4f,@location(N) [@interpolate(flat) ]name:type,...} -- RETURNED by the vertex entry and
1235 // TAKEN as the fragment entry's parameter (see the entry emitters; reads/writes qualify vo./vin.
1236 // through M_VIOMODE). Emitted ONCE, at the first K_VARY the loop reaches, by walking every K_VARY;
1237 // each node is traced by ITS OWN arm visit (never inside the walk), so the WGSL trace matches the
1238 // GLSL loop-head trace exactly. Before S7 a vertex-stage varying became a COMMENT and a
1239 // fragment-stage one REFUSED; GLSL keeps its module-scope [flat ]out|in declarations unchanged.
1240 let t2: *u8 = wg_ty(sir_get(m, d, SIR_TY))
1241 if (t2 as i64) == 0 { sir_refuse(m, "wgsl: varying of a type outside the covered subset" as *u8); return 0 - 1 }
1242 if wg_name_is(m, d, "bpos" as *u8) == 1 { sir_refuse(m, "wgsl: a varying named bpos collides with the interstage struct's reserved @builtin(position) member; rename it" as *u8); return 0 - 1 }
1243 if wg_decl_kind_first(m, K_VARY) == d {
1244 p = eb_put(out, p, cap, "struct VIO{@builtin(position) bpos:vec4f," as *u8)
1245 var vd: i64 = m[M_DECLH]
1246 while vd != 0 {
1247 if sir_get(m, vd, SIR_KIND) == K_VARY {
1248 let vt: *u8 = wg_ty(sir_get(m, vd, SIR_TY))
1249 if (vt as i64) == 0 { sir_refuse(m, "wgsl: varying of a type outside the covered subset" as *u8); return 0 - 1 }
1250 p = eb_put(out, p, cap, "@location(" as *u8)
1251 p = eb_num(out, p, cap, sir_get(m, vd, SIR_A))
1252 p = eb_put(out, p, cap, ") " as *u8)
1253 if sir_get(m, vd, SIR_B) == 1 { p = eb_put(out, p, cap, "@interpolate(flat) " as *u8) }
1254 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, vd, SIR_NAME)))
1255 p = eb_put(out, p, cap, ":" as *u8)
1256 p = eb_put(out, p, cap, vt)
1257 p = eb_put(out, p, cap, "," as *u8)
1258 }
1259 vd = sir_get(m, vd, SIR_NEXT)
1260 }
1261 p = eb_put(out, p, cap, "}\n" as *u8)
1262 }
1263 }
1264 // R-D (2026-09-04): a struct declaration -- `struct Hit{pos:vec3f,d:f32,}` (the WGSL member separator is
1265 // the comma and a trailing comma is legal, so the emitter has one shape). Traced HERE because this
1266 // backend traces per arm; members through wg_tyname; the same refusals as the GLSL arm, so both
1267 // backends cover exactly the same source.
1268 if k == K_STRUCT {
1269 tr_add(trace, tcap, tn, d)
1270 p = eb_put(out, p, cap, "struct " as *u8)
1271 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
1272 p = eb_put(out, p, cap, "{" as *u8)
1273 var mb: i64 = sir_get(m, d, SIR_A)
1274 while mb != 0 {
1275 tr_add(trace, tcap, tn, mb)
1276 if wg_is_texty(sir_get(m, mb, SIR_TY)) == 1 { sir_refuse(m, "wgsl: texture-typed struct member -- a texture is a bound resource, never a value; refused in both dialects" as *u8); return 0 - 1 }
1277 let mt: *u8 = wg_tyname(m, sir_get(m, mb, SIR_TY))
1278 if (mt as i64) == 0 { sir_refuse(m, "wgsl: struct member of a type outside the covered subset" as *u8); return 0 - 1 }
1279 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, mb, SIR_NAME)))
1280 p = eb_put(out, p, cap, ":" as *u8)
1281 p = eb_put(out, p, cap, mt)
1282 p = eb_put(out, p, cap, "," as *u8)
1283 mb = sir_get(m, mb, SIR_NEXT)
1284 }
1285 p = eb_put(out, p, cap, "}\n" as *u8)
1286 }
1287 // S1 (2026-09-04): before this line a K_ATTRIB was traced and then DROPPED -- zero bytes, no
1288 // refusal, and a trace that still matched GLSL's. Vertex inputs are @location entry parameters
1289 // in WGSL and this backend does not derive them yet, so the honest answer is a named refusal.
1290 if k == K_ATTRIB {
1291 tr_add(trace, tcap, tn, d)
1292 // S6 (2026-09-05): a vertex attribute is a @location entry PARAMETER in WGSL (emitted in the
1293 // vertex entry signature below), never a module-scope declaration -- nothing is emitted here,
1294 // exactly as K_FRAGOUT emits nothing and becomes the fragment entry's return type. Traced here so
1295 // the WGSL trace matches the GLSL arm, which DOES emit it module-scope (layout(location=N) in ...).
1296 if stage != STAGE_VERTEX { sir_refuse(m, "wgsl: vertex attribute declaration (K_ATTRIB) outside a vertex stage -- attributes are vertex-stage inputs; refused rather than emitted where nothing feeds them" as *u8); return 0 - 1 }
1297 if (wg_ty(sir_get(m, d, SIR_TY)) as i64) == 0 { sir_refuse(m, "wgsl: vertex attribute of a type outside the covered subset" as *u8); return 0 - 1 }
1298 }
1299 // S5 (2026-09-04): the fragment output is the entry's RETURN TYPE in WGSL, so NO declaration is
1300 // emitted for it -- but it IS traced, because both backends CONSUME the node and trace identity is
1301 // the equivalence oracle on a box with no GPU. A backend that silently skipped it would produce a
1302 // shorter trace, which is exactly what that oracle exists to catch.
1303 if k == K_FRAGOUT {
1304 tr_add(trace, tcap, tn, d)
1305 if stage != STAGE_FRAGMENT { sir_refuse(m, "wgsl: fragment output declaration (K_FRAGOUT) outside a fragment stage -- only the fragment stage has a colour output; refused rather than accepted where nothing can return it" as *u8); return 0 - 1 }
1306 if wg_decl_kind_count(m, K_FRAGOUT) > 1 { sir_refuse(m, "wgsl: more than one fragment output declared -- multiple render targets are their own rung; refused rather than returning the first and silently dropping the rest" as *u8); return 0 - 1 }
1307 if (wg_ty(sir_get(m, d, SIR_TY)) as i64) == 0 { sir_refuse(m, "wgsl: fragment output of a type outside the covered subset" as *u8); return 0 - 1 }
1308 }
1309 // S3 (2026-09-04): a texture is a module-scope binding var, OUTSIDE struct U, at a binding DERIVED
1310 // from declaration order (see WG_BIND_TEX_FIRST). Only texture_3d<u32> is lowered: a sampled
1311 // texture_2d<f32> needs a sampler binding this backend does not declare, so it refuses by name.
1312 if k == K_TEXTURE {
1313 tr_add(trace, tcap, tn, d)
1314 let ttk: i64 = sir_get(m, d, SIR_TY)
1315 if ttk != T_TEX3U { if ttk != T_TEX2F { sir_refuse(m, "wgsl: texture type outside the covered subset -- texture_3d<u32> (textureLoad) and texture_2d<f32> (textureSample with a derived companion sampler) are lowered; refused rather than guessed" as *u8); return 0 - 1 } }
1316 let tb: i64 = wg_tex_binding(m, d)
1317 if wg_storage_at(m, tb) != 0 { sir_refuse(m, "wgsl: derived texture binding collides with a storage buffer declared at the same binding -- declare the storage buffer (sir_storage) above the texture bindings" as *u8); return 0 - 1 }
1318 p = eb_put(out, p, cap, "@group(" as *u8)
1319 p = eb_num(out, p, cap, wg_group(m))
1320 p = eb_put(out, p, cap, ")@binding(" as *u8)
1321 p = eb_num(out, p, cap, tb)
1322 p = eb_put(out, p, cap, ")var " as *u8)
1323 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
1324 p = eb_put(out, p, cap, ":" as *u8)
1325 p = eb_put(out, p, cap, wg_ty(ttk))
1326 p = eb_put(out, p, cap, ";\n" as *u8)
1327 // GE54 (2026-09-05): a sampled texture_2d<f32> carries a DERIVED companion sampler `<name>_s` at the
1328 // next binding (wg_tex_binding counts a 2D texture as two slots, so tb+1 is reserved and no later
1329 // binding collides). GLSL folds both into one combined sampler2D; WGSL keeps texture and sampler apart.
1330 if ttk == T_TEX2F {
1331 p = eb_put(out, p, cap, "@group(" as *u8)
1332 p = eb_num(out, p, cap, wg_group(m))
1333 p = eb_put(out, p, cap, ")@binding(" as *u8)
1334 p = eb_num(out, p, cap, tb + 1)
1335 p = eb_put(out, p, cap, ")var " as *u8)
1336 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
1337 p = eb_put(out, p, cap, "_s:sampler;\n" as *u8)
1338 }
1339 }
1340 d = sir_get(m, d, SIR_NEXT)
1341 }
1342 // GE43: storage buffers, one @binding each. WGSL has them; GLSL ES 3.00 does not (its backend
1343 // refuses the kind by name), so this pass has no twin on the GLSL side BY DESIGN.
1344 d = m[M_DECLH]
1345 while d != 0 {
1346 if sir_get(m, d, SIR_KIND) == K_STORAGE {
1347 tr_add(trace, tcap, tn, d)
1348 let t4: *u8 = wg_ty(sir_get(m, d, SIR_TY))
1349 if (t4 as i64) == 0 { sir_refuse(m, "wgsl: storage element type outside the covered subset" as *u8); return 0 - 1 }
1350 p = eb_put(out, p, cap, "@group(" as *u8)
1351 p = eb_num(out, p, cap, wg_group(m))
1352 p = eb_put(out, p, cap, ")@binding(" as *u8)
1353 p = eb_num(out, p, cap, sir_get(m, d, SIR_A))
1354 if sir_get(m, d, SIR_B) == 1 { p = eb_put(out, p, cap, ")var<storage,read_write> " as *u8) } else { p = eb_put(out, p, cap, ")var<storage,read> " as *u8) }
1355 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
1356 p = eb_put(out, p, cap, ":array<" as *u8)
1357 if sir_get(m, d, SIR_C) == 1 {
1358 p = eb_put(out, p, cap, "atomic<" as *u8)
1359 p = eb_put(out, p, cap, t4)
1360 p = eb_put(out, p, cap, ">" as *u8)
1361 } else { p = eb_put(out, p, cap, t4) }
1362 p = eb_put(out, p, cap, ">;\n" as *u8)
1363 }
1364 d = sir_get(m, d, SIR_NEXT)
1365 }
1366 var f: i64 = m[M_FUNCH]
1367 while f != 0 {
1368 tr_add(trace, tcap, tn, f)
1369 m[M_CURFN] = f
1370 if wg_fn_is_plain(m, f, stage) == 1 {
1371 // R-E (2026-09-04): struct returns and struct parameters spell through wg_tyname (see the GLSL twin).
1372 let rt2: *u8 = wg_tyname(m, sir_get(m, f, SIR_TY))
1373 if (rt2 as i64) == 0 { sir_refuse(m, "wgsl: return type outside the covered subset" as *u8); return 0 - 1 }
1374 p = eb_put(out, p, cap, "fn " as *u8)
1375 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, f, SIR_NAME)))
1376 p = eb_put(out, p, cap, "(" as *u8)
1377 var pb: i64 = sir_get(m, f, SIR_A)
1378 var pg: i64 = 1
1379 while pb != 0 {
1380 if pg == 0 { p = eb_put(out, p, cap, "," as *u8) }
1381 pg = 0
1382 tr_add(trace, tcap, tn, pb)
1383 let pt2: *u8 = wg_tyname(m, sir_get(m, pb, SIR_TY))
1384 if (pt2 as i64) == 0 { sir_refuse(m, "wgsl: parameter type outside the covered subset" as *u8); return 0 - 1 }
1385 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, pb, SIR_NAME)))
1386 p = eb_put(out, p, cap, ":" as *u8)
1387 p = eb_put(out, p, cap, pt2)
1388 pb = sir_get(m, pb, SIR_NEXT)
1389 }
1390 // GE55 (2026-09-05): a function that returns nothing has NO arrow in WGSL -- `fn upk(){` -- because
1391 // `->void` is not WGSL and a browser refuses the whole module. Measured on the first void non-entry
1392 // function this backend ever emitted (the world pass upk); GLSL already spelled `void upk(){` correctly.
1393 if sir_get(m, f, SIR_TY) == T_VOID { p = eb_put(out, p, cap, "){\n" as *u8) } else {
1394 p = eb_put(out, p, cap, ")->" as *u8)
1395 p = eb_put(out, p, cap, rt2)
1396 p = eb_put(out, p, cap, "{\n" as *u8)
1397 }
1398 } else { if stage == STAGE_VERTEX {
1399 // S4: the vertex entry binds vertex_index itself; a declared parameter is an input this backend
1400 // does not derive yet (K_ATTRIB refuses for the same reason) -- refused rather than dropped.
1401 if sir_get(m, f, SIR_A) != 0 { sir_refuse(m, "wgsl: vertex entry parameter -- vertex inputs are not derived from the declaration yet (the vertex_index builtin is bound by the backend); refused rather than silently dropped" as *u8); return 0 - 1 }
1402 p = eb_put(out, p, cap, "@vertex fn " as *u8)
1403 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, f, SIR_NAME)))
1404 p = eb_put(out, p, cap, "(@builtin(vertex_index) vi:u32" as *u8)
1405 // S12a (2026-09-05): the instance index is bound ONLY when the module read it (sir_builtin set M_USESII),
1406 // so every module that never asks keeps a byte-identical signature. GLSL needs no declaration.
1407 if m[M_USESII] == 1 { p = eb_put(out, p, cap, ",@builtin(instance_index) iidx:u32" as *u8) }
1408 // S6 (2026-09-05): declared vertex attributes are @location entry parameters, appended after the
1409 // backend-bound vertex_index in declaration order. GLSL binds them module-scope; WGSL binds them
1410 // here. The location is the attribute's own SIR_A, so a mesh declaring aP/aJ/aW/aN/aUV/aHS derives
1411 // its own signature, and the fullscreen triangle (no attributes) is byte-identical to before.
1412 // Not traced here: the K_ATTRIB was traced once in the declarations loop, matching the GLSL arm.
1413 var vsa: i64 = m[M_DECLH]
1414 while vsa != 0 {
1415 if sir_get(m, vsa, SIR_KIND) == K_ATTRIB {
1416 p = eb_put(out, p, cap, ",@location(" as *u8)
1417 p = eb_num(out, p, cap, sir_get(m, vsa, SIR_A))
1418 p = eb_put(out, p, cap, ") " as *u8)
1419 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, vsa, SIR_NAME)))
1420 p = eb_put(out, p, cap, ":" as *u8)
1421 p = eb_put(out, p, cap, wg_ty(sir_get(m, vsa, SIR_TY)))
1422 }
1423 vsa = sir_get(m, vsa, SIR_NEXT)
1424 }
1425 // S7 (2026-09-05): with varyings declared the vertex entry RETURNS the interstage struct VIO --
1426 // `var vo:VIO;` opens the body, the position assignment and every varying write land in vo.<name>
1427 // (wg_stmts / wg_expr read M_VIOMODE=1), and `return vo;` closes it after the body. With none
1428 // declared the entry keeps ->@builtin(position) vec4f and `return <expr>;` -- byte-identical.
1429 if wg_decl_kind_count(m, K_VARY) > 0 {
1430 p = eb_put(out, p, cap, ")->VIO{\nvar vo:VIO;\n" as *u8)
1431 m[M_VIOMODE] = 1
1432 } else {
1433 p = eb_put(out, p, cap, ")->@builtin(position) vec4f{\n" as *u8)
1434 }
1435 } else { if stage == STAGE_COMPUTE {
1436 // S4: the compute entry binds global_invocation_id itself (wgsl_compute_stage); same rule.
1437 if sir_get(m, f, SIR_A) != 0 { sir_refuse(m, "wgsl: compute entry parameter -- the compute entry binds global_invocation_id itself; a declared parameter is not derived yet, refused rather than silently dropped" as *u8); return 0 - 1 }
1438 p = wgsl_compute_stage(m, f, out, p, cap)
1439 } else {
1440 p = eb_put(out, p, cap, "@fragment fn " as *u8)
1441 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, f, SIR_NAME)))
1442 p = eb_put(out, p, cap, "(" as *u8)
1443 var fp: i64 = sir_get(m, f, SIR_A)
1444 var ff: i64 = 1
1445 // S7 (2026-09-05): with varyings declared the fragment entry TAKES the interstage struct -- `vin:VIO`
1446 // -- and every varying read qualifies vin.<name> (M_VIOMODE=2). @builtin(position) then arrives as
1447 // vin.bpos, so a declared position parameter (S4) FOLDS into it: traced here (identity with the GLSL
1448 // arm, which traces it in its own loop) and not emitted, because a second @builtin(position)
1449 // binding is invalid WGSL. Any other parameter still refuses by name.
1450 if wg_decl_kind_count(m, K_VARY) > 0 {
1451 var fq: i64 = fp
1452 while fq != 0 {
1453 tr_add(trace, tcap, tn, fq)
1454 if sir_get(m, fq, SIR_A) != P_BUILTIN_POSITION { sir_refuse(m, "wgsl: fragment entry parameter that is not the @builtin(position) input -- varyings arrive through the interstage struct vin:VIO, never as parameters; refused rather than guessed" as *u8); return 0 - 1 }
1455 fq = sir_get(m, fq, SIR_NEXT)
1456 }
1457 fp = 0
1458 p = eb_put(out, p, cap, "vin:VIO" as *u8)
1459 m[M_VIOMODE] = 2
1460 }
1461 // S4 (2026-09-04): the fragment entry signature is DERIVED from the declared parameters -- it was
1462 // the literal "()->@location(0) vec4f{". The single covered input is @builtin(position); any
1463 // other parameter is an input this backend cannot bind yet (a @location varying) and refuses
1464 // by name. Zero parameters derive to exactly the bytes the literal used to carry.
1465 while fp != 0 {
1466 if ff == 0 { p = eb_put(out, p, cap, "," as *u8) }
1467 ff = 0
1468 tr_add(trace, tcap, tn, fp)
1469 if sir_get(m, fp, SIR_A) != P_BUILTIN_POSITION { sir_refuse(m, "wgsl: fragment entry parameter that is not the @builtin(position) input -- a located (@location) fragment input is not derived yet; refused rather than guessed" as *u8); return 0 - 1 }
1470 p = eb_put(out, p, cap, "@builtin(position) " as *u8)
1471 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, fp, SIR_NAME)))
1472 p = eb_put(out, p, cap, ":" as *u8)
1473 p = eb_put(out, p, cap, wg_ty(T_V4F))
1474 fp = sir_get(m, fp, SIR_NEXT)
1475 }
1476 // S5 (2026-09-04): THE RETURN HALF OF THE SIGNATURE IS DERIVED TOO. It was the literal
1477 // ")->@location(0) vec4f{" -- so the location and the type were unreadable constants rather than
1478 // data, the same defect S4 had just removed from the PARAMETER half of this very line. Both
1479 // halves now come from declarations. A fragment that only discards declares no output and gets
1480 // no return type; one that returns a value with none declared refuses rather than assuming.
1481 let fo2: i64 = wg_fragout(m)
1482 if fo2 == 0 {
1483 if wg_chain_returns_value(m, sir_get(m, f, SIR_B)) == 1 { sir_refuse(m, "wgsl: fragment entry returns a value with no declared fragment output -- declare it with sir_fragout (K_FRAGOUT) so the @location and the type are data; refused rather than assuming @location(0) vec4f" as *u8); return 0 - 1 }
1484 p = eb_put(out, p, cap, "){\n" as *u8)
1485 } else {
1486 p = eb_put(out, p, cap, ")->@location(" as *u8)
1487 p = eb_num(out, p, cap, sir_get(m, fo2, SIR_A))
1488 p = eb_put(out, p, cap, ") " as *u8)
1489 p = eb_put(out, p, cap, wg_ty(sir_get(m, fo2, SIR_TY)))
1490 p = eb_put(out, p, cap, "{\n" as *u8)
1491 // S12c-5 (2026-09-05): a body that ASSIGNS the declared output (the hand cast fragment's `fc=...;return;`
1492 // shape) gets the output as a local variable; every void return inside it returns that variable (wg_stmts
1493 // reads M_WGFRAGOUT) and one trailing `return fc;` closes the body when its last statement is not a return.
1494 // A body that RETURNS its value (the world pass) is untouched: no local, no trailing return, byte-identical.
1495 if wg_chain_assigns(m, sir_get(m, f, SIR_B), sir_cstr(m, sir_get(m, fo2, SIR_NAME))) == 1 {
1496 p = eb_put(out, p, cap, "var " as *u8)
1497 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, fo2, SIR_NAME)))
1498 p = eb_put(out, p, cap, ":" as *u8)
1499 p = eb_put(out, p, cap, wg_ty(sir_get(m, fo2, SIR_TY)))
1500 p = eb_put(out, p, cap, ";\n" as *u8)
1501 m[M_WGFRAGOUT] = fo2
1502 }
1503 }
1504 } } }
1505 p = wg_stmts(m, sir_get(m, f, SIR_B), out, p, cap, trace, tcap, tn)
1506 // S7: a vertex entry that returns the interstage struct closes with `return vo;`; the mode is cleared
1507 // after EVERY function so a helper declared after an entry cannot inherit the vo./vin. qualification.
1508 if m[M_VIOMODE] == 1 { p = eb_put(out, p, cap, "return vo;\n" as *u8) }
1509 m[M_VIOMODE] = 0
1510 // S12c-5: a fragment entry carrying its output as a local closes with `return fc;` unless its last statement already
1511 // returns; the word is cleared after EVERY function so a helper declared after the entry cannot inherit it.
1512 if m[M_WGFRAGOUT] != 0 {
1513 if wg_chain_last_is_return(m, sir_get(m, f, SIR_B)) == 0 {
1514 p = eb_put(out, p, cap, "return " as *u8)
1515 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, m[M_WGFRAGOUT], SIR_NAME)))
1516 p = eb_put(out, p, cap, ";\n" as *u8)
1517 }
1518 m[M_WGFRAGOUT] = 0
1519 }
1520 p = eb_put(out, p, cap, "}\n" as *u8)
1521 f = sir_get(m, f, SIR_NEXT)
1522 }
1523 m[M_CURFN] = 0
1524 if sir_refused(m) != 0 { return 0 - 1 }
1525 if p + 1 < cap { out[p] = 0 as u8 }
1526 return p
1527}
1528
1529// ---- THE SHADER, AUTHORED IN NISHILANG --------------------------------------------------------
1530// This function IS the shader source. No GLSL and no WGSL is written anywhere in this estate for
1531// this stage any more -- both dialects above are emitted from exactly these calls.
1532//
1533// vertex stage: fullscreen triangle
1534// var v: vec2 = vec2(float((vertex_index << 1) & 2), float(vertex_index & 2))
1535// position = vec4(v * 2.0 - 1.0, 0.0, 1.0)
1536func shsrc_fullscreen_tri(m: *i64) -> i64 {
1537 let fn: i64 = sir_func(m, "main" as *u8, T_VOID)
1538 let vi1: i64 = sir_builtin(m, "vertex_index" as *u8, T_I32)
1539 let sh: i64 = sir_bin(m, "<<" as *u8, vi1, sir_lit(m, "1" as *u8, T_U32), T_I32)
1540 let m1: i64 = sir_bin(m, "&" as *u8, sh, sir_lit(m, "2" as *u8, T_I32), T_I32)
1541 let vi2: i64 = sir_builtin(m, "vertex_index" as *u8, T_I32)
1542 let m2: i64 = sir_bin(m, "&" as *u8, vi2, sir_lit(m, "2" as *u8, T_I32), T_I32)
1543 let c1: i64 = sir_ctor(m, T_V2F)
1544 sir_arg(m, c1, sir_cast(m, m1, T_F32))
1545 sir_arg(m, c1, sir_cast(m, m2, T_F32))
1546 sir_stmt(m, fn, sir_var(m, "v" as *u8, T_V2F, c1))
1547 let mul: i64 = sir_bin(m, "*" as *u8, sir_ident(m, "v" as *u8, T_V2F), sir_lit(m, "2.0" as *u8, T_F32), T_V2F)
1548 let sub: i64 = sir_bin(m, "-" as *u8, mul, sir_lit(m, "1.0" as *u8, T_F32), T_V2F)
1549 let c2: i64 = sir_ctor(m, T_V4F)
1550 sir_arg(m, c2, sub)
1551 sir_arg(m, c2, sir_lit(m, "0.0" as *u8, T_F32))
1552 sir_arg(m, c2, sir_lit(m, "1.0" as *u8, T_F32))
1553 sir_stmt(m, fn, sir_assign(m, sir_builtin(m, "position" as *u8, T_V4F), c2))
1554 return fn
1555}
1556
1557// GE43 -- THE FIRST KERNEL PRIMITIVE, AUTHORED IN NISHILANG: a depth test resolved by atomicMin over
1558// a u32 depth buffer. This is the byte a software rasterizer cannot skip -- every tile, every
1559// covered fragment, one atomicMin -- and it is INTEGER end to end, which is the determinism exceed
1560// the gameengine board claims over the float fixed-function pipelines of WebGL2 and its ancestors.
1561// compute stage, WG_WORKGROUP invocations per workgroup:
1562// storage depth: array<atomic<u32>> @binding(1) read_write
1563// storage zin: array<u32> @binding(2) read
1564// var i: u32 = global_invocation_id.x
1565// atomicMin(&depth[i], zin[i])
1566func shsrc_depth_min(m: *i64) -> i64 {
1567 sir_storage(m, "depth" as *u8, T_U32, 1, 1, 1)
1568 sir_storage(m, "zin" as *u8, T_U32, 2, 0, 0)
1569 let fn: i64 = sir_func(m, "main" as *u8, T_VOID)
1570 let gx: i64 = sir_swz(m, sir_builtin(m, "global_invocation_id" as *u8, T_V3U), "x" as *u8, T_U32)
1571 sir_stmt(m, fn, sir_var(m, "i" as *u8, T_U32, gx))
1572 let tgt: i64 = sir_index(m, sir_ident(m, "depth" as *u8, T_U32), sir_ident(m, "i" as *u8, T_U32), T_U32)
1573 let src: i64 = sir_index(m, sir_ident(m, "zin" as *u8, T_U32), sir_ident(m, "i" as *u8, T_U32), T_U32)
1574 sir_stmt(m, fn, sir_expr(m, sir_atomic(m, "atomicMin" as *u8, tgt, src, T_U32)))
1575 return fn
1576}
1577
1578func wg_puts(s: *u8) -> i64 { var n: i64 = 0; while s[n] != (0 as u8) { n = n + 1 } sys_write(1, s, n); return 0 }
1579
1580func wg_streq(a: *u8, b: *u8) -> i64 {
1581 var i: i64 = 0
1582 while a[i] != (0 as u8) { if a[i] != b[i] { return 0 } i = i + 1 }
1583 if b[i] != (0 as u8) { return 0 }
1584 return 1
1585}
1586
1587// `nx_wgsl compute` -- the GE43 kernel through BOTH backends: WGSL emits, GLSL refuses BY NAME.
1588// nx_wgsl_compute_gate asserts these bytes exactly, so this output IS the contract.
1589func wg_compute_demo() -> i64 {
1590 let m: *i64 = sir_new()
1591 shsrc_depth_min(m)
1592 let wb: *u8 = sys_mmap(WG_EMIT_CAP)
1593 let wt: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
1594 let wn: *i64 = sys_mmap(WG_NUMBUF) as *i64
1595 wn[0] = 0
1596 let wl: i64 = wgsl_emit_module(m, STAGE_COMPUTE, wb, WG_EMIT_CAP, wt, WG_TRACE_CAP, wn)
1597 wg_puts("=== NX-WGSL GE43: COMPUTE STAGE -- storage buffers, atomics, global_invocation_id, ONE NishiLang source ===\n\n--- WGSL ---\n" as *u8)
1598 if wl > 0 { sys_write(1, wb, wl) }
1599 let nb: *u8 = sys_mmap(WG_NUMBUF)
1600 var q: i64 = 0
1601 wg_puts("\nwgsl_bytes=" as *u8)
1602 q = eb_num(nb, 0, WG_NUMBUF, wl); nb[q] = 0 as u8; wg_puts(nb)
1603 wg_puts(" wgsl_nodes=" as *u8)
1604 q = eb_num(nb, 0, WG_NUMBUF, wn[0]); nb[q] = 0 as u8; wg_puts(nb)
1605 wg_puts(" wgsl_refused=" as *u8)
1606 if sir_refused(m) != 0 { wg_puts(sir_cstr(m, sir_refused(m))) } else { wg_puts("NONE" as *u8) }
1607 // THE GLSL SIDE MUST REFUSE BY NAME. A WebGL2 program that silently dropped the storage buffers
1608 // would compile, link, run and draw nothing, forever -- the failure this backend exists to make impossible.
1609 let m2: *i64 = sir_new()
1610 shsrc_depth_min(m2)
1611 let gb: *u8 = sys_mmap(WG_EMIT_CAP)
1612 let gt: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
1613 let gn: *i64 = sys_mmap(WG_NUMBUF) as *i64
1614 gn[0] = 0
1615 let gl: i64 = glsl_emit_module(m2, STAGE_COMPUTE, gb, WG_EMIT_CAP, gt, WG_TRACE_CAP, gn)
1616 wg_puts(" glsl_compute_rc=" as *u8)
1617 q = eb_num(nb, 0, WG_NUMBUF, gl); nb[q] = 0 as u8; wg_puts(nb)
1618 wg_puts(" glsl_compute_named=" as *u8)
1619 if sir_refused(m2) != 0 { wg_puts(sir_cstr(m2, sir_refused(m2))) } else { wg_puts("NONE" as *u8) }
1620 // NEG-CONTROL -- the GLSL refusal must be the STAGE refusal, not a later accident: emit the same
1621 // kernel as a GLSL FRAGMENT stage and the storage DECLARATION must refuse by its own name.
1622 let m3: *i64 = sir_new()
1623 shsrc_depth_min(m3)
1624 let g3: *u8 = sys_mmap(WG_EMIT_CAP)
1625 let t3: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
1626 let n3: *i64 = sys_mmap(WG_NUMBUF) as *i64
1627 n3[0] = 0
1628 let r3: i64 = glsl_emit_module(m3, STAGE_FRAGMENT, g3, WG_EMIT_CAP, t3, WG_TRACE_CAP, n3)
1629 wg_puts(" glsl_fragment_of_kernel_rc=" as *u8)
1630 q = eb_num(nb, 0, WG_NUMBUF, r3); nb[q] = 0 as u8; wg_puts(nb)
1631 wg_puts(" glsl_fragment_of_kernel_named=" as *u8)
1632 if sir_refused(m3) != 0 { wg_puts(sir_cstr(m3, sir_refused(m3))) } else { wg_puts("NONE" as *u8) }
1633 wg_puts("\n" as *u8)
1634 return 0
1635}
1636
1637// ---- `nx_wgsl decls` -- THE DECLARATION PROBES (S1..S4, 2026-09-04) --------------------------------
1638// One module through one backend, printed the way every other verb prints: the emitted text (when it
1639// emitted), then `<label>_rc=` and `<label>_named=` on ONE line for nx_wgsl_gate to anchor on. The
1640// refusal that fired is printed VERBATIM so the gate asserts WHICH rule fired, never merely that one did.
1641func wg_probe(m: *i64, stage: i64, label: *u8, dialect_wgsl: i64, trace: *i64, tn: *i64) -> i64 {
1642 let buf: *u8 = sys_mmap(WG_EMIT_CAP)
1643 let nb: *u8 = sys_mmap(WG_NUMBUF)
1644 tn[0] = 0
1645 var rc: i64 = 0
1646 if dialect_wgsl == 1 { rc = wgsl_emit_module(m, stage, buf, WG_EMIT_CAP, trace, WG_TRACE_CAP, tn) } else { rc = glsl_emit_module(m, stage, buf, WG_EMIT_CAP, trace, WG_TRACE_CAP, tn) }
1647 wg_puts("--- " as *u8); wg_puts(label)
1648 if dialect_wgsl == 1 { wg_puts(" WGSL ---\n" as *u8) } else { wg_puts(" GLSL ---\n" as *u8) }
1649 if rc > 0 { sys_write(1, buf, rc) }
1650 wg_puts(label); wg_puts("_rc=" as *u8)
1651 var q: i64 = eb_num(nb, 0, WG_NUMBUF, rc); nb[q] = 0 as u8; wg_puts(nb)
1652 wg_puts(" " as *u8); wg_puts(label); wg_puts("_named=" as *u8)
1653 if sir_refused(m) != 0 { wg_puts(sir_cstr(m, sir_refused(m))) } else { wg_puts("NONE" as *u8) }
1654 wg_puts("\n" as *u8)
1655 return rc
1656}
1657
1658// Element-wise trace identity: same count AND same ids in the same order. The oracle main() applies
1659// inline, extracted once so the probes cannot drift from it.
1660func wg_trace_eq(a: *i64, an: i64, b: *i64, bn: i64) -> i64 {
1661 if an != bn { return 0 }
1662 var i: i64 = 0
1663 while i < an { if a[i] != b[i] { return 0 } i = i + 1 }
1664 return 1
1665}
1666
1667// A minimal fragment stage: one constant colour. The declaration probes need a fragment FUNCTION to
1668// reach the fragment-stage decl pass; this is the smallest one that is a real fragment program.
1669// fragment stage: return vec4(1.0, 0.0, 0.0, 1.0)
1670func shsrc_frag_const(m: *i64) -> i64 {
1671 sir_fragout(m, "fc" as *u8, T_V4F, 0)
1672 let fn: i64 = sir_func(m, "main" as *u8, T_VOID)
1673 let c: i64 = sir_ctor(m, T_V4F)
1674 sir_arg(m, c, sir_lit(m, "1.0" as *u8, T_F32))
1675 sir_arg(m, c, sir_lit(m, "0.0" as *u8, T_F32))
1676 sir_arg(m, c, sir_lit(m, "0.0" as *u8, T_F32))
1677 sir_arg(m, c, sir_lit(m, "1.0" as *u8, T_F32))
1678 sir_stmt(m, fn, sir_return(m, c))
1679 return fn
1680}
1681
1682// POSITIVE CONTROL for the declaration guards -- the fullscreen triangle with ONE scalar uniform folded
1683// into the clip transform. A deny-guard that has only ever refused is unverified (a guard that refuses
1684// everything passes every negative test), so the same declaration pass must be shown to ADMIT a scalar
1685// uniform; the identifier is then read through it in both dialects.
1686// uniform scale: f32
1687// vertex stage: var v = vec2(...); v = v * scale; position = vec4(v*2.0-1.0, 0.0, 1.0)
1688func shsrc_fullscreen_tri_scaled(m: *i64) -> i64 {
1689 sir_uniform(m, "scale" as *u8, T_F32, 0)
1690 let fn: i64 = shsrc_fullscreen_tri(m)
1691 // splice `v = v * scale` between the two statements the triangle already carries
1692 let s1: i64 = sir_get(m, fn, SIR_B)
1693 let s2: i64 = sir_get(m, s1, SIR_NEXT)
1694 let mul: i64 = sir_bin(m, "*" as *u8, sir_ident(m, "v" as *u8, T_V2F), sir_ident(m, "scale" as *u8, T_F32), T_V2F)
1695 let asg: i64 = sir_assign(m, sir_ident(m, "v" as *u8, T_V2F), mul)
1696 sir_set(m, s1, SIR_NEXT, asg)
1697 sir_set(m, asg, SIR_NEXT, s2)
1698 return fn
1699}
1700
1701// S2 NEG-CONTROL -- the triangle with a uniform `k` AND a local `k`: the local shadows the uniform, so the
1702// read is the bare `k`, never `u.k`. A resolver that qualified on name alone would fail this.
1703// uniform k: f32
1704// vertex stage: var v = vec2(...); var k = 2.0; v = v * k; position = ...
1705func shsrc_fullscreen_tri_shadowlocal(m: *i64) -> i64 {
1706 sir_uniform(m, "k" as *u8, T_F32, 0)
1707 let fn: i64 = shsrc_fullscreen_tri(m)
1708 let s1: i64 = sir_get(m, fn, SIR_B)
1709 let s2: i64 = sir_get(m, s1, SIR_NEXT)
1710 let lk: i64 = sir_var(m, "k" as *u8, T_F32, sir_lit(m, "2.0" as *u8, T_F32))
1711 let mul: i64 = sir_bin(m, "*" as *u8, sir_ident(m, "v" as *u8, T_V2F), sir_ident(m, "k" as *u8, T_F32), T_V2F)
1712 let asg: i64 = sir_assign(m, sir_ident(m, "v" as *u8, T_V2F), mul)
1713 sir_set(m, s1, SIR_NEXT, lk)
1714 sir_set(m, lk, SIR_NEXT, asg)
1715 sir_set(m, asg, SIR_NEXT, s2)
1716 return fn
1717}
1718
1719// S2 NEG-CONTROL -- a plain function whose PARAMETER is named like a uniform: `fn f(k:f32)` reads its own
1720// `k`, never `u.k`.
1721// uniform k: f32
1722// func f(k: f32) -> f32 { return k * 2.0 }
1723func shsrc_plain_shadowparam(m: *i64) -> i64 {
1724 sir_uniform(m, "k" as *u8, T_F32, 0)
1725 let fn: i64 = sir_func(m, "f" as *u8, T_F32)
1726 sir_param(m, fn, "k" as *u8, T_F32)
1727 sir_stmt(m, fn, sir_return(m, sir_bin(m, "*" as *u8, sir_ident(m, "k" as *u8, T_F32), sir_lit(m, "2.0" as *u8, T_F32), T_F32)))
1728 return fn
1729}
1730
1731// S3 COVERAGE -- a plain function reading a 3D u32 texture beside one scalar uniform: the texture must come
1732// out as a binding var OUTSIDE struct U in WGSL (struct U carries only the scalar) and as a sampler
1733// uniform in GLSL, and the texture identifier is read BARE in both (it is not a uniform).
1734// uniform scale: f32 ; texture vox: texture_3d<u32>
1735// func vox_at(x: i32, y: i32, z: i32) -> u32 { return texelFetch(vox, ivec3(x, y, z), 0).x }
1736// K_PRIVATE fixture (GE55): module-scope private state -- `var<private>` in WGSL, a bare global in GLSL -- a scalar
1737// and an array, written by one function and read bare by another, beside a uniform of a DIFFERENT name so the
1738// qualifier rule is exercised (u.q is qualified, gk and pv never are). STAGE_PLAIN: no entry point.
1739func shsrc_private_demo(m: *i64) -> i64 {
1740 sir_uniform(m, "q" as *u8, T_F32, 0)
1741 sir_private(m, "gk" as *u8, T_F32, 0)
1742 sir_private(m, "pv" as *u8, T_V4F, 2)
1743 let f: i64 = sir_func(m, "upk" as *u8, T_VOID)
1744 sir_stmt(m, f, sir_assign(m, sir_ident(m, "gk" as *u8, T_F32), sir_bin(m, "*" as *u8, sir_ident(m, "q" as *u8, T_F32), sir_lit(m, "2.0" as *u8, T_F32), T_F32)))
1745 let ctor: i64 = sir_ctor(m, T_V4F)
1746 sir_arg(m, ctor, sir_ident(m, "gk" as *u8, T_F32))
1747 sir_stmt(m, f, sir_assign(m, sir_index(m, sir_ident(m, "pv" as *u8, T_V4F), sir_lit(m, "0" as *u8, T_I32), T_V4F), ctor))
1748 let g: i64 = sir_func(m, "rd" as *u8, T_F32)
1749 sir_stmt(m, g, sir_return(m, sir_bin(m, "+" as *u8, sir_ident(m, "gk" as *u8, T_F32), sir_swz(m, sir_index(m, sir_ident(m, "pv" as *u8, T_V4F), sir_lit(m, "0" as *u8, T_I32), T_V4F), "x" as *u8, T_F32), T_F32)))
1750 return 0
1751}
1752
1753// GE54 fixture: a sampled texture_2d<f32> -- the cast fragment's need (wc_mob_tex). Declares `atlas` (T_TEX2F) and a
1754// plain function that samples it at a uv param; GLSL lowers to sampler2D + texture(), WGSL to a texture + a derived
1755// companion sampler + textureSample(). STAGE_PLAIN (no entry point) -- a decl+function module, valid to compile.
1756func shsrc_tex2d_sample(m: *i64) -> i64 {
1757 sir_texture(m, "atlas" as *u8, T_TEX2F)
1758 let f: i64 = sir_func(m, "smp" as *u8, T_V4F)
1759 sir_param(m, f, "uv" as *u8, T_V2F)
1760 sir_stmt(m, f, sir_return(m, sir_texsample(m, sir_ident(m, "atlas" as *u8, T_TEX2F), sir_ident(m, "uv" as *u8, T_V2F))))
1761 return 0
1762}
1763
1764func shsrc_tex_plain(m: *i64) -> i64 {
1765 sir_uniform(m, "scale" as *u8, T_F32, 0)
1766 sir_texture(m, "vox" as *u8, T_TEX3U)
1767 let fn: i64 = sir_func(m, "vox_at" as *u8, T_U32)
1768 sir_param(m, fn, "x" as *u8, T_I32)
1769 sir_param(m, fn, "y" as *u8, T_I32)
1770 sir_param(m, fn, "z" as *u8, T_I32)
1771 let c: i64 = sir_ctor(m, T_V3I)
1772 sir_arg(m, c, sir_ident(m, "x" as *u8, T_I32))
1773 sir_arg(m, c, sir_ident(m, "y" as *u8, T_I32))
1774 sir_arg(m, c, sir_ident(m, "z" as *u8, T_I32))
1775 let ld: i64 = sir_texload(m, sir_ident(m, "vox" as *u8, T_TEX3U), c, sir_lit(m, "0" as *u8, T_I32))
1776 sir_stmt(m, fn, sir_return(m, sir_swz(m, ld, "x" as *u8, T_U32)))
1777 return fn
1778}
1779
1780// S4 COVERAGE -- a fragment that READS its position. The WGSL entry signature is derived from the declared
1781// parameter (`@builtin(position) pos:vec4f`) and the body reads `pos`; GLSL reads it as gl_FragCoord.
1782// fragment stage: param pos = @builtin(position)
1783// return vec4(pos.x, pos.y, 0.0, 1.0)
1784func shsrc_frag_pos(m: *i64) -> i64 {
1785 sir_fragout(m, "fc" as *u8, T_V4F, 0)
1786 let fn: i64 = sir_func(m, "main" as *u8, T_VOID)
1787 sir_param_position(m, fn, "pos" as *u8)
1788 let c: i64 = sir_ctor(m, T_V4F)
1789 sir_arg(m, c, sir_swz(m, sir_ident(m, "pos" as *u8, T_V4F), "x" as *u8, T_F32))
1790 sir_arg(m, c, sir_swz(m, sir_ident(m, "pos" as *u8, T_V4F), "y" as *u8, T_F32))
1791 sir_arg(m, c, sir_lit(m, "0.0" as *u8, T_F32))
1792 sir_arg(m, c, sir_lit(m, "1.0" as *u8, T_F32))
1793 sir_stmt(m, fn, sir_return(m, c))
1794 return fn
1795}
1796
1797// S4 NEG-CONTROL -- a fragment that reads the position BUILTIN without declaring the parameter: an undeclared
1798// input, refused by name (before S4 it emitted the placeholder identifier POSITION with no refusal).
1799// fragment stage: return vec4(position.x, 0.0, 0.0, 1.0) -- no parameter declared
1800func shsrc_frag_pos_undeclared(m: *i64) -> i64 {
1801 sir_fragout(m, "fc" as *u8, T_V4F, 0)
1802 let fn: i64 = sir_func(m, "main" as *u8, T_VOID)
1803 let c: i64 = sir_ctor(m, T_V4F)
1804 sir_arg(m, c, sir_swz(m, sir_builtin(m, "position" as *u8, T_V4F), "x" as *u8, T_F32))
1805 sir_arg(m, c, sir_lit(m, "0.0" as *u8, T_F32))
1806 sir_arg(m, c, sir_lit(m, "0.0" as *u8, T_F32))
1807 sir_arg(m, c, sir_lit(m, "1.0" as *u8, T_F32))
1808 sir_stmt(m, fn, sir_return(m, c))
1809 return fn
1810}
1811
1812// S4 NEG-CONTROL -- a fragment entry with a PLAIN parameter (no builtin binding): neither backend can bind it
1813// yet (it would be a @location varying), so both refuse by name rather than dropping it from the signature.
1814// fragment stage: param uv: vec2 (plain) return vec4(1.0, 0.0, 0.0, 1.0)
1815func shsrc_frag_plainparam(m: *i64) -> i64 {
1816 sir_fragout(m, "fc" as *u8, T_V4F, 0)
1817 let fn: i64 = sir_func(m, "main" as *u8, T_VOID)
1818 sir_param(m, fn, "uv" as *u8, T_V2F)
1819 let c: i64 = sir_ctor(m, T_V4F)
1820 sir_arg(m, c, sir_lit(m, "1.0" as *u8, T_F32))
1821 sir_arg(m, c, sir_lit(m, "0.0" as *u8, T_F32))
1822 sir_arg(m, c, sir_lit(m, "0.0" as *u8, T_F32))
1823 sir_arg(m, c, sir_lit(m, "1.0" as *u8, T_F32))
1824 sir_stmt(m, fn, sir_return(m, c))
1825 return fn
1826}
1827
1828// S5 COVERAGE -- a fragment that DISCARDS and returns nothing. It declares NO output, and neither backend
1829// requires one: the output rule binds to what the body does, not to the stage. This is the POSITIVE control
1830// for that precision -- without it, "a fragment must declare an output" would be a guard that refuses a
1831// legal program, and a deny-guard whose false-positive rate nobody measured is worse than none.
1832// fragment stage: discard
1833func shsrc_frag_discard(m: *i64) -> i64 {
1834 let fn: i64 = sir_func(m, "main" as *u8, T_VOID)
1835 sir_stmt(m, fn, sir_discard(m))
1836 return fn
1837}
1838
1839// S5 NEG-CONTROL -- a fragment that RETURNS A VALUE with no declared output. This is the exact source that
1840// used to emit `void main(){ return vec4(1.0,0.0,0.0,1.0); }` -- invalid GLSL ES 3.00 twice over, shipped
1841// with no refusal because nothing pinned the GLSL fragment bytes. Both backends now refuse it by name.
1842// fragment stage: return vec4(1.0, 0.0, 0.0, 1.0) -- no output declared
1843func shsrc_frag_noout(m: *i64) -> i64 {
1844 let fn: i64 = sir_func(m, "main" as *u8, T_VOID)
1845 let c: i64 = sir_ctor(m, T_V4F)
1846 sir_arg(m, c, sir_lit(m, "1.0" as *u8, T_F32))
1847 sir_arg(m, c, sir_lit(m, "0.0" as *u8, T_F32))
1848 sir_arg(m, c, sir_lit(m, "0.0" as *u8, T_F32))
1849 sir_arg(m, c, sir_lit(m, "1.0" as *u8, T_F32))
1850 sir_stmt(m, fn, sir_return(m, c))
1851 return fn
1852}
1853
1854// S5 COVERAGE -- the output at a NON-ZERO location, proving the @location and the layout() qualifier are
1855// DATA and not the constant 0 they used to be. GLSL spells it `layout(location=2) out vec4 fc;` and WGSL
1856// `->@location(2) vec4f`; at location 0 both collapse to the bare form the shipping FSH already uses.
1857func shsrc_frag_loc2(m: *i64) -> i64 {
1858 sir_fragout(m, "fc" as *u8, T_V4F, 2)
1859 let fn: i64 = sir_func(m, "main" as *u8, T_VOID)
1860 let c: i64 = sir_ctor(m, T_V4F)
1861 sir_arg(m, c, sir_lit(m, "1.0" as *u8, T_F32))
1862 sir_arg(m, c, sir_lit(m, "0.0" as *u8, T_F32))
1863 sir_arg(m, c, sir_lit(m, "0.0" as *u8, T_F32))
1864 sir_arg(m, c, sir_lit(m, "1.0" as *u8, T_F32))
1865 sir_stmt(m, fn, sir_return(m, c))
1866 return fn
1867}
1868
1869// S5 NEG-CONTROL -- a fragment output declared on a VERTEX stage. Only the fragment stage has a colour
1870// output; a vertex stage that declared one would emit a variable nothing can ever write.
1871func shsrc_vert_fragout(m: *i64) -> i64 {
1872 sir_fragout(m, "fc" as *u8, T_V4F, 0)
1873 return shsrc_fullscreen_tri(m)
1874}
1875
1876// S5 NEG-CONTROL -- TWO fragment outputs. Multiple render targets are a real feature and their own rung;
1877// emitting the first and dropping the second would be the silent mistranslation this backend forbids.
1878func shsrc_frag_twoout(m: *i64) -> i64 {
1879 sir_fragout(m, "fc" as *u8, T_V4F, 0)
1880 sir_fragout(m, "fc2" as *u8, T_V4F, 1)
1881 return shsrc_frag_const_body(m)
1882}
1883
1884// the shared body the two-output control needs (shsrc_frag_const declares an output of its own)
1885func shsrc_frag_const_body(m: *i64) -> i64 {
1886 let fn: i64 = sir_func(m, "main" as *u8, T_VOID)
1887 let c: i64 = sir_ctor(m, T_V4F)
1888 sir_arg(m, c, sir_lit(m, "1.0" as *u8, T_F32))
1889 sir_arg(m, c, sir_lit(m, "0.0" as *u8, T_F32))
1890 sir_arg(m, c, sir_lit(m, "0.0" as *u8, T_F32))
1891 sir_arg(m, c, sir_lit(m, "1.0" as *u8, T_F32))
1892 sir_stmt(m, fn, sir_return(m, c))
1893 return fn
1894}
1895
1896// S5 NEG-CONTROL -- a SAMPLED texture read. wg_expr used to emit textureSample(t,samp,c) against an
1897// undeclared `samp`; the declaration pass had refused the same missing binding for two weeks. GLSL has no
1898// such gap (its texture() needs no separate sampler object), so this is a one-sided refusal BY DESIGN --
1899// the mirror image of K_STORAGE, which GLSL refuses and WGSL emits.
1900// texture vox: texture_3d<u32> ; func s(uv: vec2) -> vec4 { return textureSample(vox, uv) }
1901func shsrc_texsample(m: *i64) -> i64 {
1902 sir_texture(m, "vox" as *u8, T_TEX3U)
1903 let fn: i64 = sir_func(m, "s" as *u8, T_V4F)
1904 sir_param(m, fn, "uv" as *u8, T_V2F)
1905 let sm: i64 = sir_texsample(m, sir_ident(m, "vox" as *u8, T_TEX3U), sir_ident(m, "uv" as *u8, T_V2F))
1906 sir_stmt(m, fn, sir_return(m, sm))
1907 return fn
1908}
1909
1910// R-A / R-C fixture (2026-09-04): one plain function using a select and an immutable local. Expected bytes:
1911// GLSL float t=((c>0)?a:b); WGSL let t:f32=select(b,a,(c>0));
1912func shsrc_select_let(m: *i64) -> i64 {
1913 let f: i64 = sir_func(m, "pick" as *u8, T_F32)
1914 sir_param(m, f, "a" as *u8, T_F32)
1915 sir_param(m, f, "b" as *u8, T_F32)
1916 sir_param(m, f, "c" as *u8, T_I32)
1917 let cond: i64 = sir_bin(m, ">" as *u8, sir_ident(m, "c" as *u8, T_I32), sir_lit(m, "0" as *u8, T_I32), T_BOOL)
1918 let sel: i64 = sir_select(m, cond, sir_ident(m, "a" as *u8, T_F32), sir_ident(m, "b" as *u8, T_F32), T_F32)
1919 sir_stmt(m, f, sir_let(m, "t" as *u8, T_F32, sel))
1920 sir_stmt(m, f, sir_return(m, sir_ident(m, "t" as *u8, T_F32)))
1921 return f
1922}
1923
1924// R-B fixture (2026-09-04): a counted loop written ONCE as builder sugar (sir_for_until) -- the counter is a
1925// mutable local, the exit test and the step ride the shared S_IF/S_LOOP/S_ASSIGN arms, so the two dialects
1926// differ only in the loop keyword and the declaration spelling. Expected bytes are asserted by the gate.
1927func shsrc_for_until(m: *i64) -> i64 {
1928 let f: i64 = sir_func(m, "sum" as *u8, T_I32)
1929 sir_param(m, f, "n" as *u8, T_I32)
1930 sir_stmt(m, f, sir_var(m, "s" as *u8, T_I32, sir_lit(m, "0" as *u8, T_I32)))
1931 let init: i64 = sir_var(m, "i" as *u8, T_I32, sir_lit(m, "0" as *u8, T_I32))
1932 let until: i64 = sir_bin(m, ">=" as *u8, sir_ident(m, "i" as *u8, T_I32), sir_ident(m, "n" as *u8, T_I32), T_BOOL)
1933 let step: i64 = sir_assign(m, sir_ident(m, "i" as *u8, T_I32), sir_bin(m, "+" as *u8, sir_ident(m, "i" as *u8, T_I32), sir_lit(m, "1" as *u8, T_I32), T_I32))
1934 let body: i64 = sir_assign(m, sir_ident(m, "s" as *u8, T_I32), sir_bin(m, "+" as *u8, sir_ident(m, "s" as *u8, T_I32), sir_ident(m, "i" as *u8, T_I32), T_I32))
1935 sir_for_until(m, f, init, until, step, body)
1936 sir_stmt(m, f, sir_return(m, sir_ident(m, "s" as *u8, T_I32)))
1937 return f
1938}
1939
1940// R-D fixture (2026-09-04): one struct, a struct-typed local built by the struct's own constructor (an E_CALL
1941// named after the struct), a member write, and two member reads -- one through a nested swizzle. Expected bytes
1942// are asserted by the gate; the two dialects differ only in the declaration spelling and the local's keyword.
1943func shsrc_struct(m: *i64) -> i64 {
1944 let st: i64 = sir_struct(m, "Hit" as *u8)
1945 sir_member(m, st, "pos" as *u8, T_V3F)
1946 sir_member(m, st, "d" as *u8, T_F32)
1947 let hty: i64 = sir_struct_ty(st)
1948 let f: i64 = sir_func(m, "hitd" as *u8, T_F32)
1949 sir_param(m, f, "p" as *u8, T_V3F)
1950 sir_param(m, f, "k" as *u8, T_F32)
1951 let ctor: i64 = sir_call(m, "Hit" as *u8, hty)
1952 sir_arg(m, ctor, sir_ident(m, "p" as *u8, T_V3F))
1953 sir_arg(m, ctor, sir_ident(m, "k" as *u8, T_F32))
1954 sir_stmt(m, f, sir_var(m, "h" as *u8, hty, ctor))
1955 let hd: i64 = sir_member_of(m, sir_ident(m, "h" as *u8, hty), "d" as *u8, T_F32)
1956 sir_stmt(m, f, sir_assign(m, hd, sir_bin(m, "*" as *u8, sir_member_of(m, sir_ident(m, "h" as *u8, hty), "d" as *u8, T_F32), sir_lit(m, "2.0" as *u8, T_F32), T_F32)))
1957 let px: i64 = sir_swz(m, sir_member_of(m, sir_ident(m, "h" as *u8, hty), "pos" as *u8, T_V3F), "x" as *u8, T_F32)
1958 sir_stmt(m, f, sir_return(m, sir_bin(m, "+" as *u8, sir_member_of(m, sir_ident(m, "h" as *u8, hty), "d" as *u8, T_F32), px, T_F32)))
1959 return f
1960}
1961
1962// R-E fixture (2026-09-04): ONE function shape for the struct-returning march the two hand shaders spell two ways
1963// (GLSL out-params vs WGSL struct return). GLSL ES 3.00 returns structs, so the canonical shape is the struct
1964// return in BOTH dialects: mk builds and returns a Hit, useh takes a Hit PARAMETER and reads a member off the
1965// call's result directly. Expected bytes are asserted by the gate.
1966func shsrc_struct_ret(m: *i64) -> i64 {
1967 let st: i64 = sir_struct(m, "Hit" as *u8)
1968 sir_member(m, st, "pos" as *u8, T_V3F)
1969 sir_member(m, st, "d" as *u8, T_F32)
1970 let hty: i64 = sir_struct_ty(st)
1971 let f1: i64 = sir_func(m, "mk" as *u8, hty)
1972 sir_param(m, f1, "p" as *u8, T_V3F)
1973 sir_param(m, f1, "k" as *u8, T_F32)
1974 let ctor: i64 = sir_call(m, "Hit" as *u8, hty)
1975 sir_arg(m, ctor, sir_ident(m, "p" as *u8, T_V3F))
1976 sir_arg(m, ctor, sir_ident(m, "k" as *u8, T_F32))
1977 sir_stmt(m, f1, sir_var(m, "h" as *u8, hty, ctor))
1978 sir_stmt(m, f1, sir_assign(m, sir_member_of(m, sir_ident(m, "h" as *u8, hty), "d" as *u8, T_F32), sir_bin(m, "*" as *u8, sir_ident(m, "k" as *u8, T_F32), sir_lit(m, "2.0" as *u8, T_F32), T_F32)))
1979 sir_stmt(m, f1, sir_return(m, sir_ident(m, "h" as *u8, hty)))
1980 let f2: i64 = sir_func(m, "useh" as *u8, T_F32)
1981 sir_param(m, f2, "h" as *u8, hty)
1982 sir_param(m, f2, "k" as *u8, T_F32)
1983 let call: i64 = sir_call(m, "mk" as *u8, hty)
1984 sir_arg(m, call, sir_member_of(m, sir_ident(m, "h" as *u8, hty), "pos" as *u8, T_V3F))
1985 sir_arg(m, call, sir_ident(m, "k" as *u8, T_F32))
1986 sir_stmt(m, f2, sir_return(m, sir_bin(m, "+" as *u8, sir_member_of(m, call, "d" as *u8, T_F32), sir_member_of(m, sir_ident(m, "h" as *u8, hty), "d" as *u8, T_F32), T_F32)))
1987 return f2
1988}
1989
1990// ---- R-F (2026-09-04, GE44): THE UNIFORM LAYOUT IS DERIVED, NEVER HAND-COUNTED --------------------------
1991// The shipping page packs struct U by hand-counted float indices beside a hand-written declaration: two copies
1992// of one shape. WGSL defines the layout mechanically (spec, memory layouts, mirrored as gameengine.refs
1993// ge-wgsl-spec): AlignOf/SizeOf per type, array stride = roundUp(AlignOf(E), SizeOf(E)), struct size rounded up
1994// to its alignment, and in the uniform address space an array stride that is a multiple of 16 -- an array<f32,N>
1995// member is INVALID there, so it is refused by name here rather than laid out into a buffer the GPU rejects.
1996// `nx_wgsl layout` prints one row per uniform in declaration order plus the struct size; nx_wgsl_gate holds the
1997// shipping packer's own numbers (pal at 112, palf at 304, 96 floats = 384 bytes) as the KAT.
1998const WG_UNIFORM_STRIDE_MULTIPLE: i64 = 16
1999func wg_round_up(al: i64, n: i64) -> i64 { return ((n + al - 1) / al) * al }
2000func wg_align_of(t: i64) -> i64 {
2001 if t == T_F32 { return 4 }
2002 if t == T_I32 { return 4 }
2003 if t == T_U32 { return 4 }
2004 if t == T_BOOL { return 4 }
2005 if t == T_V2F { return 8 }
2006 if t == T_V3F { return 16 }
2007 if t == T_V4F { return 16 }
2008 if t == T_V3I { return 16 }
2009 if t == T_V3U { return 16 }
2010 return 0
2011}
2012func wg_size_of(t: i64) -> i64 {
2013 if t == T_F32 { return 4 }
2014 if t == T_I32 { return 4 }
2015 if t == T_U32 { return 4 }
2016 if t == T_BOOL { return 4 }
2017 if t == T_V2F { return 8 }
2018 if t == T_V3F { return 12 }
2019 if t == T_V4F { return 16 }
2020 if t == T_V3I { return 12 }
2021 if t == T_V3U { return 12 }
2022 return 0
2023}
2024// Writes `uniform|<name>|offset=|size=|align=|stride=|count=` rows for every K_UNIFORM in declaration order and a
2025// final `struct_u_size=` row; returns the struct size, or -1 with the refusal named in the module.
2026// The summary key is a PARAMETER (GE55, 2026-09-05): a capture that lays out several modules must give each its own
2027// key, or a reader anchored on `struct_u_size=` takes whichever module printed last -- measured on the live gate: the
2028// world block's 384 read as a fixture's 4 the moment a second layout shared the key. One writer per key.
2029func wg_uniform_layout(m: *i64, out: *u8, pos: i64, cap: i64) -> i64 { return wg_uniform_layout_k(m, out, pos, cap, "struct_u_size=" as *u8) }
2030func wg_uniform_layout_k(m: *i64, out: *u8, pos: i64, cap: i64, key: *u8) -> i64 {
2031 var p: i64 = pos
2032 var off: i64 = 0
2033 var maxal: i64 = 0
2034 var d: i64 = m[M_DECLH]
2035 while d != 0 {
2036 if sir_get(m, d, SIR_KIND) == K_UNIFORM {
2037 var ty: i64 = sir_get(m, d, SIR_TY)
2038 var n: i64 = sir_get(m, d, SIR_A)
2039 // S12c-2b: float[N] is laid out as the array<vec4f,ceil(N/4)> the struct emitter declares -- ONE rule
2040 // (wg_f32arr_vec4n), so the ruler and the emitter cannot disagree about the same declaration; the row
2041 // carries `f32n=` so a reader can see the lowering happened and from what.
2042 var f32n: i64 = 0
2043 if ty == T_F32 { if n > 0 { f32n = n; ty = T_V4F; n = wg_f32arr_vec4n(n) } }
2044 let al: i64 = wg_align_of(ty)
2045 let sz: i64 = wg_size_of(ty)
2046 if al == 0 { sir_refuse(m, "wgsl: uniform of a type with no layout rule in this backend (a texture is a bound resource, a struct-typed uniform is its own rung) -- refused rather than laid out by guess" as *u8); return 0 - 1 }
2047 var stride: i64 = 0
2048 var total: i64 = sz
2049 if n > 0 {
2050 stride = wg_round_up(al, sz)
2051 if (stride - (stride / WG_UNIFORM_STRIDE_MULTIPLE) * WG_UNIFORM_STRIDE_MULTIPLE) != 0 { sir_refuse(m, "wgsl: uniform array element stride is not a multiple of 16 -- the uniform address space requires it (spec: an array<f32,N> member of a uniform struct is invalid); use a vec4f element as the shipping pal/palf do. Refused rather than laid out into a buffer the GPU rejects" as *u8); return 0 - 1 }
2052 total = stride * n
2053 }
2054 off = wg_round_up(al, off)
2055 p = eb_put(out, p, cap, "uniform|" as *u8)
2056 p = eb_put(out, p, cap, sir_cstr(m, sir_get(m, d, SIR_NAME)))
2057 p = eb_put(out, p, cap, "|offset=" as *u8)
2058 p = eb_num(out, p, cap, off)
2059 p = eb_put(out, p, cap, "|size=" as *u8)
2060 p = eb_num(out, p, cap, total)
2061 p = eb_put(out, p, cap, "|align=" as *u8)
2062 p = eb_num(out, p, cap, al)
2063 p = eb_put(out, p, cap, "|stride=" as *u8)
2064 p = eb_num(out, p, cap, stride)
2065 p = eb_put(out, p, cap, "|count=" as *u8)
2066 p = eb_num(out, p, cap, n)
2067 if f32n > 0 { p = eb_put(out, p, cap, "|f32n=" as *u8); p = eb_num(out, p, cap, f32n) }
2068 p = eb_put(out, p, cap, "\n" as *u8)
2069 off = off + total
2070 if al > maxal { maxal = al }
2071 }
2072 d = sir_get(m, d, SIR_NEXT)
2073 }
2074 var size: i64 = 0
2075 if maxal > 0 { size = wg_round_up(maxal, off) }
2076 p = eb_put(out, p, cap, key)
2077 p = eb_num(out, p, cap, size)
2078 p = eb_put(out, p, cap, "\n" as *u8)
2079 if p + 1 < cap { out[p] = 0 as u8 }
2080 return size
2081}
2082// R-F fixture: the shipping world pass's uniform block, in its declaration order, plus one uniform read.
2083func shsrc_world_uniforms(m: *i64) -> i64 {
2084 // R-G: the uniform block has ONE owner -- the world shader source (ws_world_uniforms); this fixture reads it.
2085 ws_world_uniforms(m)
2086 let f: i64 = sir_func(m, "tk" as *u8, T_F32)
2087 sir_param(m, f, "k" as *u8, T_F32)
2088 sir_stmt(m, f, sir_return(m, sir_bin(m, "*" as *u8, sir_ident(m, "t" as *u8, T_F32), sir_ident(m, "k" as *u8, T_F32), T_F32)))
2089 return f
2090}
2091// `nx_wgsl layout`: the world uniform block through both backends (the emitted struct U is the WGSL spelling the
2092// hand shader carries), then the derived layout rows, then the stride neg-control on an array<f32,8> member.
2093// R-G0 fixture (2026-09-04): an uninitialised local and a unary negation -- `var v:f32; v=(-a); return v;` in both
2094// spellings. Expected bytes are asserted by the gate.
2095func shsrc_neg_uninit(m: *i64) -> i64 {
2096 let f: i64 = sir_func(m, "nu" as *u8, T_F32)
2097 sir_param(m, f, "a" as *u8, T_F32)
2098 sir_stmt(m, f, sir_var(m, "v" as *u8, T_F32, 0))
2099 sir_stmt(m, f, sir_assign(m, sir_ident(m, "v" as *u8, T_F32), sir_neg(m, sir_ident(m, "a" as *u8, T_F32), T_F32)))
2100 sir_stmt(m, f, sir_return(m, sir_ident(m, "v" as *u8, T_F32)))
2101 return f
2102}
2103// `nx_wgsl world` (R-G): THE WORLD SHADER (nx_world_shader_src) through both backends -- the fragment module
2104// (uniforms, the voxel texture, struct Hit, every function, the entry) and the backend's own fullscreen-triangle
2105// vertex stage -- printed the way every verb prints, for nx_game_page_emit to capture and for the gate to pin.
2106func wg_world_demo() -> i64 {
2107 wg_puts("=== NX-WGSL world: the world pass written ONCE, emitted to both dialects ===\n" as *u8)
2108 let tr: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2109 let tn: *i64 = sys_mmap(WG_NUMBUF) as *i64
2110 let nb: *u8 = sys_mmap(WG_NUMBUF)
2111 var q: i64 = 0
2112 let m1: *i64 = sir_new()
2113 shsrc_world(m1)
2114 let gt1: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2115 let gn1: *i64 = sys_mmap(WG_NUMBUF) as *i64
2116 wg_probe(m1, STAGE_FRAGMENT, "world_glsl" as *u8, 0, gt1, gn1)
2117 wg_probe(m1, STAGE_FRAGMENT, "world_wgsl" as *u8, 1, tr, tn)
2118 wg_puts("world_trace_equal=" as *u8)
2119 q = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt1, gn1[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2120 wg_puts("\n" as *u8)
2121 let m2: *i64 = sir_new()
2122 shsrc_fullscreen_tri(m2)
2123 wg_probe(m2, STAGE_VERTEX, "worldvs_glsl" as *u8, 0, gt1, gn1)
2124 wg_probe(m2, STAGE_VERTEX, "worldvs_wgsl" as *u8, 1, tr, tn)
2125 return 0
2126}
2127// S12c (2026-09-05): `nx_wgsl cast [<glsl-out>]` -- THE CHARACTER CAST vertex stage (nx_cast_shader_src, transcribed slice by
2128// slice from the hand MVS) through both backends, printed the way every verb prints; when a path is given the emitted GLSL is
2129// ALSO written there VERBATIM, so nx_glsl_tokdiff can measure it against buildroot/knowledge/compare/cast_mvs_hand.glsl (the
2130// pre-declared accept rule: canonical-token prefix per slice, IDENTICAL for the whole stage). The WGSL probe is expected to
2131// REFUSE BY NAME until S12c-2b lowers the hand's float[12] uniform arrays (uniform-space stride) -- printed, never hidden.
2132const WG_MODE_0644: i64 = 420
2133// emit the GLSL of module m for `stage` and write it VERBATIM to outp, printing `<label>_written=<bytes> fd_ok= path=`
2134func wg_glsl_to_path(m: *i64, stage: i64, outp: *u8, label: *u8) -> i64 {
2135 let nb: *u8 = sys_mmap(WG_NUMBUF)
2136 var q: i64 = 0
2137 let buf: *u8 = sys_mmap(WG_EMIT_CAP)
2138 let t2: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2139 let n2: *i64 = sys_mmap(WG_NUMBUF) as *i64
2140 n2[0] = 0
2141 let rc: i64 = glsl_emit_module(m, stage, buf, WG_EMIT_CAP, t2, WG_TRACE_CAP, n2)
2142 wg_puts(label)
2143 if rc > 0 {
2144 let fd: i64 = sys_openat_wr(outp, WG_MODE_0644)
2145 if fd >= 0 { sys_write(fd, buf, rc); sys_close(fd) }
2146 wg_puts("_written=" as *u8); q = eb_num(nb, 0, WG_NUMBUF, rc); nb[q] = 0 as u8; wg_puts(nb)
2147 wg_puts(" fd_ok=" as *u8); if fd >= 0 { wg_puts("1" as *u8) } else { wg_puts("0" as *u8) }
2148 wg_puts(" path=" as *u8); wg_puts(outp); wg_puts("\n" as *u8)
2149 } else { wg_puts("_written=0 REFUSED\n" as *u8) }
2150 return rc
2151}
2152func wg_cast_demo(outp: *u8, outf: *u8) -> i64 {
2153 wg_puts("=== NX-WGSL cast: the character cast vertex stage written ONCE, emitted to both dialects ===\n" as *u8)
2154 let tr: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2155 let tn: *i64 = sys_mmap(WG_NUMBUF) as *i64
2156 let nb: *u8 = sys_mmap(WG_NUMBUF)
2157 var q: i64 = 0
2158 let m1: *i64 = sir_new()
2159 shsrc_cast_vs(m1)
2160 let gt1: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2161 let gn1: *i64 = sys_mmap(WG_NUMBUF) as *i64
2162 wg_probe(m1, STAGE_VERTEX, "cast_glsl" as *u8, 0, gt1, gn1)
2163 let m1w: *i64 = sir_new()
2164 shsrc_cast_vs(m1w)
2165 wg_probe(m1w, STAGE_VERTEX, "cast_wgsl" as *u8, 1, tr, tn)
2166 wg_puts("cast_trace_equal=" as *u8)
2167 q = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt1, gn1[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2168 wg_puts(" cast_nodes=" as *u8)
2169 q = eb_num(nb, 0, WG_NUMBUF, m1[M_NCOUNT]); nb[q] = 0 as u8; wg_puts(nb)
2170 wg_puts("\n" as *u8)
2171 // S12c-6: the node arena overflows SILENTLY (sir_node returns 0, sets M_OVER) -- printed so a truncated module cannot pass as a small one
2172 wg_puts("cast_over=" as *u8)
2173 q = eb_num(nb, 0, WG_NUMBUF, m1[M_OVER]); nb[q] = 0 as u8; wg_puts(nb)
2174 wg_puts("\n" as *u8)
2175 if (outp as i64) != 0 {
2176 let m2: *i64 = sir_new()
2177 shsrc_cast_vs(m2)
2178 wg_glsl_to_path(m2, STAGE_VERTEX, outp, "cast_glsl" as *u8)
2179 }
2180 // S12c-6 (2026-09-05): THE FRAGMENT STAGE (shsrc_cast_fs) through both backends -- its own probe pair, trace line and file,
2181 // measured by nx_glsl_tokdiff against buildroot/knowledge/compare/cast_mfs_hand.glsl exactly as the vertex stage was.
2182 let m3: *i64 = sir_new()
2183 shsrc_cast_fs(m3)
2184 let gt3: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2185 let gn3: *i64 = sys_mmap(WG_NUMBUF) as *i64
2186 wg_probe(m3, STAGE_FRAGMENT, "castfs_glsl" as *u8, 0, gt3, gn3)
2187 let m3w: *i64 = sir_new()
2188 shsrc_cast_fs(m3w)
2189 // S12 step 2: the fragment stage's resources live in bind group 1 (see M_BINDGROUP) -- the vertex stage keeps group 0
2190 m3w[M_BINDGROUP] = 1
2191 wg_probe(m3w, STAGE_FRAGMENT, "castfs_wgsl" as *u8, 1, tr, tn)
2192 wg_puts("castfs_trace_equal=" as *u8)
2193 q = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt3, gn3[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2194 wg_puts(" castfs_nodes=" as *u8)
2195 q = eb_num(nb, 0, WG_NUMBUF, m3[M_NCOUNT]); nb[q] = 0 as u8; wg_puts(nb)
2196 wg_puts(" castfs_over=" as *u8)
2197 q = eb_num(nb, 0, WG_NUMBUF, m3[M_OVER]); nb[q] = 0 as u8; wg_puts(nb)
2198 wg_puts("\n" as *u8)
2199 if (outf as i64) != 0 {
2200 let m4: *i64 = sir_new()
2201 shsrc_cast_fs(m4)
2202 wg_glsl_to_path(m4, STAGE_FRAGMENT, outf, "castfs_glsl" as *u8)
2203 }
2204 // S12 step 2 (2026-09-06): the cast structs' DERIVED byte layouts, one key per module (one writer per key -- the world
2205 // block measured what a shared key does), so the page packs each stage's u:U at the ruler's offsets, never a hand count.
2206 let lbv: *u8 = sys_mmap(WG_EMIT_CAP)
2207 let lsv: i64 = wg_uniform_layout_k(m1w, lbv, 0, WG_EMIT_CAP, "castv_struct_size=" as *u8)
2208 wg_puts("castv_layout_rc=" as *u8)
2209 q = eb_num(nb, 0, WG_NUMBUF, lsv); nb[q] = 0 as u8; wg_puts(nb)
2210 wg_puts(" rows:\n" as *u8)
2211 wg_puts(lbv)
2212 let lbf: *u8 = sys_mmap(WG_EMIT_CAP)
2213 let lsf: i64 = wg_uniform_layout_k(m3w, lbf, 0, WG_EMIT_CAP, "castf_struct_size=" as *u8)
2214 wg_puts("castf_layout_rc=" as *u8)
2215 q = eb_num(nb, 0, WG_NUMBUF, lsf); nb[q] = 0 as u8; wg_puts(nb)
2216 wg_puts(" rows:\n" as *u8)
2217 wg_puts(lbf)
2218 wg_puts("castf_bind_group=" as *u8)
2219 q = eb_num(nb, 0, WG_NUMBUF, m3w[M_BINDGROUP]); nb[q] = 0 as u8; wg_puts(nb)
2220 wg_puts("\n" as *u8)
2221 return 0
2222}
2223func wg_layout_demo() -> i64 {
2224 wg_puts("=== NX-WGSL layout: the uniform block's memory layout is DERIVED from the IR by the WGSL rules ===\n" as *u8)
2225 let tr: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2226 let tn: *i64 = sys_mmap(WG_NUMBUF) as *i64
2227 let nb: *u8 = sys_mmap(WG_NUMBUF)
2228 var q: i64 = 0
2229 let m1: *i64 = sir_new()
2230 shsrc_world_uniforms(m1)
2231 wg_probe(m1, STAGE_PLAIN, "worldu_glsl" as *u8, 0, tr, tn)
2232 wg_probe(m1, STAGE_PLAIN, "worldu_wgsl" as *u8, 1, tr, tn)
2233 let lb: *u8 = sys_mmap(WG_EMIT_CAP)
2234 let ls: i64 = wg_uniform_layout(m1, lb, 0, WG_EMIT_CAP)
2235 wg_puts(lb)
2236 wg_puts("layout_rc=" as *u8)
2237 q = eb_num(nb, 0, WG_NUMBUF, ls); nb[q] = 0 as u8; wg_puts(nb)
2238 wg_puts(" layout_named=" as *u8)
2239 if sir_refused(m1) != 0 { wg_puts(sir_cstr(m1, sir_refused(m1))) } else { wg_puts("NONE" as *u8) }
2240 wg_puts("\n" as *u8)
2241 // GE55 K_PRIVATE is INVISIBLE to the uniform layout: a module with one uniform beside private state lays out the
2242 // uniform alone (struct size 4) and never lists the private name.
2243 let m3: *i64 = sir_new()
2244 shsrc_private_demo(m3)
2245 let lb3: *u8 = sys_mmap(WG_EMIT_CAP)
2246 let ls3: i64 = wg_uniform_layout_k(m3, lb3, 0, WG_EMIT_CAP, "priv_struct_size=" as *u8)
2247 wg_puts("layoutpriv_rc=" as *u8)
2248 q = eb_num(nb, 0, WG_NUMBUF, ls3); nb[q] = 0 as u8; wg_puts(nb)
2249 wg_puts(" rows:\n" as *u8)
2250 wg_puts(lb3)
2251 // GE55 the RAW world block: the one ruler both the sim's UR_* word table and the page's NXU_SIZE are pinned to.
2252 // 40 four-byte scalars, so every offset is index*4 and the struct is exactly 160 B; the gate reads these rows.
2253 let m4: *i64 = sir_new()
2254 ws_world_uniforms_raw(m4)
2255 let lb4: *u8 = sys_mmap(WG_EMIT_CAP)
2256 let ls4: i64 = wg_uniform_layout_k(m4, lb4, 0, WG_EMIT_CAP, "raw_struct_size=" as *u8)
2257 wg_puts("layoutraw_rc=" as *u8)
2258 q = eb_num(nb, 0, WG_NUMBUF, ls4); nb[q] = 0 as u8; wg_puts(nb)
2259 wg_puts(" rows:\n" as *u8)
2260 wg_puts(lb4)
2261 // S12c-2b POSITIVE CONTROL: an array<f32,8> uniform member is LOWERED to array<vec4f,2> -- stride 16, size 32, f32n=8 --
2262 // by the same rule the struct emitter applies (wg_f32arr_vec4n), so the layout ruler and the emitted struct U agree.
2263 let m5: *i64 = sir_new()
2264 sir_uniform(m5, "w" as *u8, T_F32, 8)
2265 let lb5: *u8 = sys_mmap(WG_EMIT_CAP)
2266 let ls5: i64 = wg_uniform_layout_k(m5, lb5, 0, WG_EMIT_CAP, "f32_struct_size=" as *u8)
2267 wg_puts("layoutf32_rc=" as *u8)
2268 q = eb_num(nb, 0, WG_NUMBUF, ls5); nb[q] = 0 as u8; wg_puts(nb)
2269 wg_puts(" rows:\n" as *u8)
2270 wg_puts(lb5)
2271 // NEG-CONTROL: an array<vec2f,8> uniform member has stride 8, invalid in the uniform address space and with no lowering:
2272 // refused by name (this control moved off array<f32,8> when S12c-2b gave that case a lowering)
2273 let m2: *i64 = sir_new()
2274 sir_uniform(m2, "w" as *u8, T_V2F, 8)
2275 let lb2: *u8 = sys_mmap(WG_EMIT_CAP)
2276 let ls2: i64 = wg_uniform_layout(m2, lb2, 0, WG_EMIT_CAP)
2277 wg_puts("layoutbad_rc=" as *u8)
2278 q = eb_num(nb, 0, WG_NUMBUF, ls2); nb[q] = 0 as u8; wg_puts(nb)
2279 wg_puts(" layoutbad_named=" as *u8)
2280 if sir_refused(m2) != 0 { wg_puts(sir_cstr(m2, sir_refused(m2))) } else { wg_puts("NONE" as *u8) }
2281 wg_puts("\n" as *u8)
2282 return 0
2283}
2284
2285// S6 2026-09-05 closure bump: fixture attribute apos->aP (substring-collision fix); a prior /api/build
2286// served a stale cached artifact despite a changed src, so this comment forces a genuine recompile.
2287// S9 (2026-09-05): the ONE place a callee is re-spelled per dialect. IR call names are the WGSL spellings; GLSL ES 3.00
2288// spells the fragment derivatives dFdx/dFdy and inverseSqrt as inversesqrt (fwidth is the same word in both). Any other
2289// name passes through unchanged, and the trace carries the IR name, so trace identity across dialects is untouched.
2290// Stage refusal (derivatives are fragment-only in both dialects) is NOT decided here: the expression arms have no stage
2291// in scope; both compilers refuse a derivative outside a fragment entry at pipeline creation, which is the oracle.
2292func gl_call_name(name: *u8) -> *u8 {
2293 if wg_streq(name, "dpdx" as *u8) == 1 { return "dFdx" as *u8 }
2294 if wg_streq(name, "dpdy" as *u8) == 1 { return "dFdy" as *u8 }
2295 if wg_streq(name, "inverseSqrt" as *u8) == 1 { return "inversesqrt" as *u8 }
2296 return name
2297}
2298
2299// S8 provenance 2026-09-05 (seat fable): samplers as texture_2d+sampler pairs for the named cast set uAtl uNrm uJT uGD,
2300// texload typed by its texture, T_V2I lowered to vec2i/ivec2. This comment also bumps the build closure: the /api/build
2301// cache answered the changed source with the RELEASE twin e646b12c built by the sov lane, and the live binary is the
2302// DEBUG flavour, so a flavour-matched rebuild needs a key the cache has never seen.
2303func wg_decls_demo() -> i64 {
2304 wg_puts("=== NX-WGSL decls: declaration lowering is NAMED -- refusals, qualification, resources, entry params ===\n" as *u8)
2305 let tr: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2306 let tn: *i64 = sys_mmap(WG_NUMBUF) as *i64
2307 // NEG-CONTROL S1a -- a texture-typed K_UNIFORM must refuse, never land inside struct U
2308 let m1: *i64 = sir_new()
2309 sir_uniform(m1, "vox" as *u8, T_TEX3U, 0)
2310 shsrc_fullscreen_tri(m1)
2311 wg_probe(m1, STAGE_VERTEX, "texuniform" as *u8, 1, tr, tn)
2312 // S6 (2026-09-05) COVERAGE -- a vertex attribute lowers to a @location entry parameter in WGSL and a
2313 // module-scope `layout(location=N) in` in GLSL; emitted through BOTH backends, trace-identical (the
2314 // no-GPU equivalence oracle). It used to REFUSE (the S1b neg-control); the refusal path is now the
2315 // out-of-vertex-stage case, covered by the S6 neg-control below.
2316 let m2: *i64 = sir_new()
2317 sir_attrib(m2, "aP" as *u8, T_V3F, 0)
2318 shsrc_fullscreen_tri(m2)
2319 let gt2: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2320 let gn2: *i64 = sys_mmap(WG_NUMBUF) as *i64
2321 wg_probe(m2, STAGE_VERTEX, "attrib_glsl" as *u8, 0, gt2, gn2)
2322 wg_probe(m2, STAGE_VERTEX, "attrib" as *u8, 1, tr, tn)
2323 let nb2: *u8 = sys_mmap(WG_NUMBUF)
2324 wg_puts("attrib_trace_equal=" as *u8)
2325 var q2: i64 = eb_num(nb2, 0, WG_NUMBUF, wg_trace_eq(gt2, gn2[0], tr, tn[0])); nb2[q2] = 0 as u8; wg_puts(nb2)
2326 wg_puts("\n" as *u8)
2327 // S6 NEG-CONTROL -- a K_ATTRIB reached in a FRAGMENT stage must refuse BY NAME (attributes are vertex-only)
2328 let m2b: *i64 = sir_new()
2329 sir_attrib(m2b, "aP" as *u8, T_V3F, 0)
2330 shsrc_frag_const(m2b)
2331 wg_probe(m2b, STAGE_FRAGMENT, "attribfrag" as *u8, 1, tr, tn)
2332 // S7 (2026-09-05) COVERAGE -- varyings are ONE interstage struct in WGSL (returned by the vertex entry,
2333 // taken by the fragment entry, a flat int carried with @interpolate(flat)) and plain [flat ]out|in in
2334 // GLSL; BOTH dialects, BOTH stages, trace-identical. The old S1c neg-control (a fragment K_VARY must
2335 // refuse) is now the fragvary POSITIVE: declared-but-unread is admitted with the struct parameter in place.
2336 let m3: *i64 = sir_new()
2337 sir_vary(m3, "vcol" as *u8, T_V4F, 0, 0)
2338 shsrc_frag_const(m3)
2339 wg_probe(m3, STAGE_FRAGMENT, "fragvary" as *u8, 1, tr, tn)
2340 // vertex fixture: vcol = vec4(1,0,0,1); vii = 7 (flat i32); position = vec4(0,0,0,1)
2341 let m3v: *i64 = sir_new()
2342 sir_vary(m3v, "vcol" as *u8, T_V4F, 0, 0)
2343 sir_vary(m3v, "vii" as *u8, T_I32, 1, 1)
2344 let f3v: i64 = sir_func(m3v, "main" as *u8, T_VOID)
2345 let c3a: i64 = sir_ctor(m3v, T_V4F)
2346 sir_arg(m3v, c3a, sir_lit(m3v, "1.0" as *u8, T_F32))
2347 sir_arg(m3v, c3a, sir_lit(m3v, "0.0" as *u8, T_F32))
2348 sir_arg(m3v, c3a, sir_lit(m3v, "0.0" as *u8, T_F32))
2349 sir_arg(m3v, c3a, sir_lit(m3v, "1.0" as *u8, T_F32))
2350 sir_stmt(m3v, f3v, sir_assign(m3v, sir_ident(m3v, "vcol" as *u8, T_V4F), c3a))
2351 sir_stmt(m3v, f3v, sir_assign(m3v, sir_ident(m3v, "vii" as *u8, T_I32), sir_lit(m3v, "7" as *u8, T_I32)))
2352 let c3b: i64 = sir_ctor(m3v, T_V4F)
2353 sir_arg(m3v, c3b, sir_lit(m3v, "0.0" as *u8, T_F32))
2354 sir_arg(m3v, c3b, sir_lit(m3v, "0.0" as *u8, T_F32))
2355 sir_arg(m3v, c3b, sir_lit(m3v, "0.0" as *u8, T_F32))
2356 sir_arg(m3v, c3b, sir_lit(m3v, "1.0" as *u8, T_F32))
2357 sir_stmt(m3v, f3v, sir_assign(m3v, sir_builtin(m3v, "position" as *u8, T_V4F), c3b))
2358 let gt3v: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2359 let gn3v: *i64 = sys_mmap(WG_NUMBUF) as *i64
2360 wg_probe(m3v, STAGE_VERTEX, "varyvs_glsl" as *u8, 0, gt3v, gn3v)
2361 wg_probe(m3v, STAGE_VERTEX, "varyvs" as *u8, 1, tr, tn)
2362 let nb3: *u8 = sys_mmap(WG_NUMBUF)
2363 wg_puts("varyvs_trace_equal=" as *u8)
2364 var q3: i64 = eb_num(nb3, 0, WG_NUMBUF, wg_trace_eq(gt3v, gn3v[0], tr, tn[0])); nb3[q3] = 0 as u8; wg_puts(nb3)
2365 wg_puts("\n" as *u8)
2366 // fragment fixture: fc = vcol * float(vii) -- reads both varyings, one of them flat
2367 let m3f: *i64 = sir_new()
2368 sir_vary(m3f, "vcol" as *u8, T_V4F, 0, 0)
2369 sir_vary(m3f, "vii" as *u8, T_I32, 1, 1)
2370 sir_fragout(m3f, "fc" as *u8, T_V4F, 0)
2371 let f3f: i64 = sir_func(m3f, "main" as *u8, T_VOID)
2372 let e3: i64 = sir_bin(m3f, "*" as *u8, sir_ident(m3f, "vcol" as *u8, T_V4F), sir_cast(m3f, sir_ident(m3f, "vii" as *u8, T_I32), T_F32), T_V4F)
2373 sir_stmt(m3f, f3f, sir_return(m3f, e3))
2374 let gt3f: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2375 let gn3f: *i64 = sys_mmap(WG_NUMBUF) as *i64
2376 wg_probe(m3f, STAGE_FRAGMENT, "varyfs_glsl" as *u8, 0, gt3f, gn3f)
2377 wg_probe(m3f, STAGE_FRAGMENT, "varyfs" as *u8, 1, tr, tn)
2378 wg_puts("varyfs_trace_equal=" as *u8)
2379 q3 = eb_num(nb3, 0, WG_NUMBUF, wg_trace_eq(gt3f, gn3f[0], tr, tn[0])); nb3[q3] = 0 as u8; wg_puts(nb3)
2380 wg_puts("\n" as *u8)
2381 // S7 NEG-CONTROL -- a varying named bpos collides with the reserved position member and must refuse BY NAME
2382 let m3n: *i64 = sir_new()
2383 // (bpos is the reserved @builtin(position) member of struct VIO)
2384 sir_vary(m3n, "bpos" as *u8, T_V4F, 0, 0)
2385 shsrc_frag_const(m3n)
2386 wg_probe(m3n, STAGE_FRAGMENT, "varybpos" as *u8, 1, tr, tn)
2387 // S8 (2026-09-05) COVERAGE -- THE NAMED CAST SAMPLER SET uAtl uNrm uJT uGD: four texture_2d<f32> at DERIVED
2388 // two-slot bindings (1,3,5,7 + companion samplers 2,4,6,8); the joint table (uJT) and the garment table (uGD)
2389 // are read by INTEGER coordinate in the VERTEX stage (textureLoad / texelFetch over the new T_V2I, the load
2390 // typed vec4f by its texture), the atlas and normal map are SAMPLED in the fragment stage through the
2391 // derived companion samplers. Both dialects, both stages, trace-identical.
2392 let m8v: *i64 = sir_new()
2393 sir_texture(m8v, "uAtl" as *u8, T_TEX2F)
2394 sir_texture(m8v, "uNrm" as *u8, T_TEX2F)
2395 sir_texture(m8v, "uJT" as *u8, T_TEX2F)
2396 sir_texture(m8v, "uGD" as *u8, T_TEX2F)
2397 sir_attrib(m8v, "aJ" as *u8, T_V4F, 1)
2398 sir_vary(m8v, "vcol" as *u8, T_V4F, 0, 0)
2399 let f8v: i64 = sir_func(m8v, "main" as *u8, T_VOID)
2400 let c8j: i64 = sir_ctor(m8v, T_V2I)
2401 sir_arg(m8v, c8j, sir_cast(m8v, sir_swz(m8v, sir_ident(m8v, "aJ" as *u8, T_V4F), "x" as *u8, T_F32), T_I32))
2402 sir_arg(m8v, c8j, sir_lit(m8v, "0" as *u8, T_I32))
2403 sir_stmt(m8v, f8v, sir_assign(m8v, sir_ident(m8v, "vcol" as *u8, T_V4F), sir_texload(m8v, sir_ident(m8v, "uJT" as *u8, T_TEX2F), c8j, sir_lit(m8v, "0" as *u8, T_I32))))
2404 let c8g: i64 = sir_ctor(m8v, T_V2I)
2405 sir_arg(m8v, c8g, sir_lit(m8v, "0" as *u8, T_I32))
2406 sir_arg(m8v, c8g, sir_lit(m8v, "0" as *u8, T_I32))
2407 sir_stmt(m8v, f8v, sir_assign(m8v, sir_builtin(m8v, "position" as *u8, T_V4F), sir_texload(m8v, sir_ident(m8v, "uGD" as *u8, T_TEX2F), c8g, sir_lit(m8v, "0" as *u8, T_I32))))
2408 let gt8v: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2409 let gn8v: *i64 = sys_mmap(WG_NUMBUF) as *i64
2410 wg_probe(m8v, STAGE_VERTEX, "cast8vs_glsl" as *u8, 0, gt8v, gn8v)
2411 wg_probe(m8v, STAGE_VERTEX, "cast8vs" as *u8, 1, tr, tn)
2412 let nb8: *u8 = sys_mmap(WG_NUMBUF)
2413 wg_puts("cast8vs_trace_equal=" as *u8)
2414 var q8: i64 = eb_num(nb8, 0, WG_NUMBUF, wg_trace_eq(gt8v, gn8v[0], tr, tn[0])); nb8[q8] = 0 as u8; wg_puts(nb8)
2415 wg_puts("\n" as *u8)
2416 // S9 (2026-09-05) COVERAGE -- mat3 + derivatives + inverseSqrt. cast9vs: M = mat3(aA,aB,aC); position = vec4(M*aP, 1.0).
2417 // cast9fs: vec4(dpdx(v.x), dpdy(v.y), fwidth(v.z), inverseSqrt(v.w)) -- IR names are the WGSL spellings; the GLSL arm
2418 // re-spells dFdx/dFdy/inversesqrt through gl_call_name. Both stages, both dialects, trace-identical.
2419 let m9v: *i64 = sir_new()
2420 sir_attrib(m9v, "aP" as *u8, T_V3F, 0)
2421 sir_attrib(m9v, "aA" as *u8, T_V3F, 1)
2422 sir_attrib(m9v, "aB" as *u8, T_V3F, 2)
2423 sir_attrib(m9v, "aC" as *u8, T_V3F, 3)
2424 let f9v: i64 = sir_func(m9v, "main" as *u8, T_VOID)
2425 let c9m: i64 = sir_ctor(m9v, T_M3F)
2426 sir_arg(m9v, c9m, sir_ident(m9v, "aA" as *u8, T_V3F))
2427 sir_arg(m9v, c9m, sir_ident(m9v, "aB" as *u8, T_V3F))
2428 sir_arg(m9v, c9m, sir_ident(m9v, "aC" as *u8, T_V3F))
2429 sir_stmt(m9v, f9v, sir_let(m9v, "M" as *u8, T_M3F, c9m))
2430 let c9p: i64 = sir_ctor(m9v, T_V4F)
2431 sir_arg(m9v, c9p, sir_bin(m9v, "*" as *u8, sir_ident(m9v, "M" as *u8, T_M3F), sir_ident(m9v, "aP" as *u8, T_V3F), T_V3F))
2432 sir_arg(m9v, c9p, sir_lit(m9v, "1.0" as *u8, T_F32))
2433 sir_stmt(m9v, f9v, sir_assign(m9v, sir_builtin(m9v, "position" as *u8, T_V4F), c9p))
2434 let gt9v: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2435 let gn9v: *i64 = sys_mmap(WG_NUMBUF) as *i64
2436 wg_probe(m9v, STAGE_VERTEX, "cast9vs_glsl" as *u8, 0, gt9v, gn9v)
2437 wg_probe(m9v, STAGE_VERTEX, "cast9vs" as *u8, 1, tr, tn)
2438 let nb9c: *u8 = sys_mmap(WG_NUMBUF)
2439 wg_puts("cast9vs_trace_equal=" as *u8)
2440 var q9c: i64 = eb_num(nb9c, 0, WG_NUMBUF, wg_trace_eq(gt9v, gn9v[0], tr, tn[0])); nb9c[q9c] = 0 as u8; wg_puts(nb9c)
2441 wg_puts("\n" as *u8)
2442 let m9f: *i64 = sir_new()
2443 sir_vary(m9f, "vcol" as *u8, T_V4F, 0, 0)
2444 sir_fragout(m9f, "fc" as *u8, T_V4F, 0)
2445 let f9f: i64 = sir_func(m9f, "main" as *u8, T_VOID)
2446 let c9o: i64 = sir_ctor(m9f, T_V4F)
2447 let k9a: i64 = sir_call(m9f, "dpdx" as *u8, T_F32)
2448 sir_arg(m9f, k9a, sir_swz(m9f, sir_ident(m9f, "vcol" as *u8, T_V4F), "x" as *u8, T_F32))
2449 sir_arg(m9f, c9o, k9a)
2450 let k9b: i64 = sir_call(m9f, "dpdy" as *u8, T_F32)
2451 sir_arg(m9f, k9b, sir_swz(m9f, sir_ident(m9f, "vcol" as *u8, T_V4F), "y" as *u8, T_F32))
2452 sir_arg(m9f, c9o, k9b)
2453 let k9c: i64 = sir_call(m9f, "fwidth" as *u8, T_F32)
2454 sir_arg(m9f, k9c, sir_swz(m9f, sir_ident(m9f, "vcol" as *u8, T_V4F), "z" as *u8, T_F32))
2455 sir_arg(m9f, c9o, k9c)
2456 let k9d: i64 = sir_call(m9f, "inverseSqrt" as *u8, T_F32)
2457 sir_arg(m9f, k9d, sir_swz(m9f, sir_ident(m9f, "vcol" as *u8, T_V4F), "w" as *u8, T_F32))
2458 sir_arg(m9f, c9o, k9d)
2459 sir_stmt(m9f, f9f, sir_return(m9f, c9o))
2460 let gt9f: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2461 let gn9f: *i64 = sys_mmap(WG_NUMBUF) as *i64
2462 wg_probe(m9f, STAGE_FRAGMENT, "cast9fs_glsl" as *u8, 0, gt9f, gn9f)
2463 wg_probe(m9f, STAGE_FRAGMENT, "cast9fs" as *u8, 1, tr, tn)
2464 wg_puts("cast9fs_trace_equal=" as *u8)
2465 q9c = eb_num(nb9c, 0, WG_NUMBUF, wg_trace_eq(gt9f, gn9f[0], tr, tn[0])); nb9c[q9c] = 0 as u8; wg_puts(nb9c)
2466 wg_puts("\n" as *u8)
2467 // S12a (2026-09-05) COVERAGE -- the instance index: position = vec4(f32(instance_index), aP.y, 0, 1). WGSL binds
2468 // @builtin(instance_index) ii:u32 only in THIS module (M_USESII); GLSL reads gl_InstanceID undeclared. Trace-identical.
2469 let m10v: *i64 = sir_new()
2470 sir_attrib(m10v, "aP" as *u8, T_V3F, 0)
2471 let f10v: i64 = sir_func(m10v, "main" as *u8, T_VOID)
2472 let c10p: i64 = sir_ctor(m10v, T_V4F)
2473 sir_arg(m10v, c10p, sir_cast(m10v, sir_builtin(m10v, "instance_index" as *u8, T_I32), T_F32))
2474 sir_arg(m10v, c10p, sir_swz(m10v, sir_ident(m10v, "aP" as *u8, T_V3F), "y" as *u8, T_F32))
2475 sir_arg(m10v, c10p, sir_lit(m10v, "0.0" as *u8, T_F32))
2476 sir_arg(m10v, c10p, sir_lit(m10v, "1.0" as *u8, T_F32))
2477 sir_stmt(m10v, f10v, sir_assign(m10v, sir_builtin(m10v, "position" as *u8, T_V4F), c10p))
2478 let gt10v: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2479 let gn10v: *i64 = sys_mmap(WG_NUMBUF) as *i64
2480 wg_probe(m10v, STAGE_VERTEX, "cast10vs_glsl" as *u8, 0, gt10v, gn10v)
2481 wg_probe(m10v, STAGE_VERTEX, "cast10vs" as *u8, 1, tr, tn)
2482 let nb10: *u8 = sys_mmap(WG_NUMBUF)
2483 wg_puts("cast10vs_trace_equal=" as *u8)
2484 var q10: i64 = eb_num(nb10, 0, WG_NUMBUF, wg_trace_eq(gt10v, gn10v[0], tr, tn[0])); nb10[q10] = 0 as u8; wg_puts(nb10)
2485 wg_puts("\n" as *u8)
2486 // S12c-1 (2026-09-05) COVERAGE -- a VOID return inside the interstage-struct vertex entry: cast11vs writes vo.vcol and
2487 // returns early under an if (the hair-lock cull shape). WGSL hands back the struct (`return vo;`), GLSL says `return;`.
2488 let m11v: *i64 = sir_new()
2489 sir_attrib(m11v, "aP" as *u8, T_V3F, 0)
2490 sir_vary(m11v, "vcol" as *u8, T_V4F, 0, 0)
2491 let f11v: i64 = sir_func(m11v, "main" as *u8, T_VOID)
2492 let c11z: i64 = sir_ctor(m11v, T_V4F)
2493 sir_arg(m11v, c11z, sir_lit(m11v, "0.0" as *u8, T_F32))
2494 var tc11: i64 = 0
2495 tc11 = sir_seq(m11v, tc11, sir_assign(m11v, sir_ident(m11v, "vcol" as *u8, T_V4F), c11z))
2496 tc11 = sir_seq(m11v, tc11, sir_return(m11v, 0))
2497 sir_stmt(m11v, f11v, sir_if(m11v, sir_bin(m11v, "<" as *u8, sir_swz(m11v, sir_ident(m11v, "aP" as *u8, T_V3F), "y" as *u8, T_F32), sir_lit(m11v, "0.0" as *u8, T_F32), T_BOOL), tc11, 0))
2498 let c11c: i64 = sir_ctor(m11v, T_V4F)
2499 sir_arg(m11v, c11c, sir_ident(m11v, "aP" as *u8, T_V3F))
2500 sir_arg(m11v, c11c, sir_lit(m11v, "1.0" as *u8, T_F32))
2501 sir_stmt(m11v, f11v, sir_assign(m11v, sir_ident(m11v, "vcol" as *u8, T_V4F), c11c))
2502 let c11p: i64 = sir_ctor(m11v, T_V4F)
2503 sir_arg(m11v, c11p, sir_ident(m11v, "aP" as *u8, T_V3F))
2504 sir_arg(m11v, c11p, sir_lit(m11v, "1.0" as *u8, T_F32))
2505 sir_stmt(m11v, f11v, sir_assign(m11v, sir_builtin(m11v, "position" as *u8, T_V4F), c11p))
2506 let gt11v: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2507 let gn11v: *i64 = sys_mmap(WG_NUMBUF) as *i64
2508 wg_probe(m11v, STAGE_VERTEX, "cast11vs_glsl" as *u8, 0, gt11v, gn11v)
2509 wg_probe(m11v, STAGE_VERTEX, "cast11vs" as *u8, 1, tr, tn)
2510 let nb11: *u8 = sys_mmap(WG_NUMBUF)
2511 wg_puts("cast11vs_trace_equal=" as *u8)
2512 var q11: i64 = eb_num(nb11, 0, WG_NUMBUF, wg_trace_eq(gt11v, gn11v[0], tr, tn[0])); nb11[q11] = 0 as u8; wg_puts(nb11)
2513 wg_puts("\n" as *u8)
2514 // S12c-5 fixture (2026-09-05): a fragment that ASSIGNS its declared output and exits early with a void return -- the hand
2515 // cast fragment's shape. GLSL: `fc=...;` and `return;` (fc is an out variable). WGSL: `var fc:vec4f;` opens the body, each
2516 // void return becomes `return fc;`, a trailing `return fc;` closes it. It also carries a const local and a u-suffixed unsigned
2517 // literal -- the two other spellings the cast fragment needs in BOTH dialects. Trace-identical (the lowering emits no node).
2518 let m12f: *i64 = sir_new()
2519 sir_uniform(m12f, "a" as *u8, T_F32, 0)
2520 sir_fragout(m12f, "fc" as *u8, T_V4F, 0)
2521 let f12f: i64 = sir_func(m12f, "main" as *u8, T_VOID)
2522 let c12a: i64 = sir_ctor(m12f, T_V4F)
2523 sir_arg(m12f, c12a, sir_lit(m12f, "1.0" as *u8, T_F32))
2524 var tc12: i64 = 0
2525 tc12 = sir_seq(m12f, tc12, sir_assign(m12f, sir_ident(m12f, "fc" as *u8, T_V4F), c12a))
2526 tc12 = sir_seq(m12f, tc12, sir_return(m12f, 0))
2527 sir_stmt(m12f, f12f, sir_if(m12f, sir_bin(m12f, "<" as *u8, sir_ident(m12f, "a" as *u8, T_F32), sir_lit(m12f, "0.5" as *u8, T_F32), T_BOOL), tc12, 0))
2528 sir_stmt(m12f, f12f, sir_const(m12f, "K" as *u8, T_F32, sir_lit(m12f, "1.2" as *u8, T_F32)))
2529 sir_stmt(m12f, f12f, sir_var(m12f, "z" as *u8, T_U32, sir_lit_u(m12f, "0" as *u8)))
2530 let c12b: i64 = sir_ctor(m12f, T_V4F)
2531 sir_arg(m12f, c12b, sir_ident(m12f, "K" as *u8, T_F32))
2532 sir_stmt(m12f, f12f, sir_assign(m12f, sir_ident(m12f, "fc" as *u8, T_V4F), c12b))
2533 let gt12f: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2534 let gn12f: *i64 = sys_mmap(WG_NUMBUF) as *i64
2535 wg_probe(m12f, STAGE_FRAGMENT, "fragassign_glsl" as *u8, 0, gt12f, gn12f)
2536 wg_probe(m12f, STAGE_FRAGMENT, "fragassign_wgsl" as *u8, 1, tr, tn)
2537 let nb12: *u8 = sys_mmap(WG_NUMBUF)
2538 wg_puts("fragassign_trace_equal=" as *u8)
2539 var q12: i64 = eb_num(nb12, 0, WG_NUMBUF, wg_trace_eq(gt12f, gn12f[0], tr, tn[0])); nb12[q12] = 0 as u8; wg_puts(nb12)
2540 wg_puts("\n" as *u8)
2541 let m8f: *i64 = sir_new()
2542 sir_texture(m8f, "uAtl" as *u8, T_TEX2F)
2543 sir_texture(m8f, "uNrm" as *u8, T_TEX2F)
2544 sir_texture(m8f, "uJT" as *u8, T_TEX2F)
2545 sir_texture(m8f, "uGD" as *u8, T_TEX2F)
2546 sir_vary(m8f, "vcol" as *u8, T_V4F, 0, 0)
2547 sir_fragout(m8f, "fc" as *u8, T_V4F, 0)
2548 let f8f: i64 = sir_func(m8f, "main" as *u8, T_VOID)
2549 let s8a: i64 = sir_texsample(m8f, sir_ident(m8f, "uAtl" as *u8, T_TEX2F), sir_swz(m8f, sir_ident(m8f, "vcol" as *u8, T_V4F), "xy" as *u8, T_V2F))
2550 let s8n: i64 = sir_texsample(m8f, sir_ident(m8f, "uNrm" as *u8, T_TEX2F), sir_swz(m8f, sir_ident(m8f, "vcol" as *u8, T_V4F), "xy" as *u8, T_V2F))
2551 sir_stmt(m8f, f8f, sir_return(m8f, sir_bin(m8f, "*" as *u8, s8a, s8n, T_V4F)))
2552 let gt8f: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2553 let gn8f: *i64 = sys_mmap(WG_NUMBUF) as *i64
2554 wg_probe(m8f, STAGE_FRAGMENT, "cast8fs_glsl" as *u8, 0, gt8f, gn8f)
2555 wg_probe(m8f, STAGE_FRAGMENT, "cast8fs" as *u8, 1, tr, tn)
2556 wg_puts("cast8fs_trace_equal=" as *u8)
2557 q8 = eb_num(nb8, 0, WG_NUMBUF, wg_trace_eq(gt8f, gn8f[0], tr, tn[0])); nb8[q8] = 0 as u8; wg_puts(nb8)
2558 wg_puts("\n" as *u8)
2559 // POSITIVE CONTROL -- the same passes ADMIT a scalar uniform, in both dialects, trace-identical
2560 let m4: *i64 = sir_new()
2561 shsrc_fullscreen_tri_scaled(m4)
2562 let gt: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2563 let gn: *i64 = sys_mmap(WG_NUMBUF) as *i64
2564 wg_probe(m4, STAGE_VERTEX, "posctl_glsl" as *u8, 0, gt, gn)
2565 wg_probe(m4, STAGE_VERTEX, "posctl_wgsl" as *u8, 1, tr, tn)
2566 let nb: *u8 = sys_mmap(WG_NUMBUF)
2567 wg_puts("posctl_trace_equal=" as *u8)
2568 var q: i64 = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt, gn[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2569 wg_puts("\n" as *u8)
2570 // NEG-CONTROL S2a -- a LOCAL named like a uniform is read bare (it shadows the uniform)
2571 let m5: *i64 = sir_new()
2572 shsrc_fullscreen_tri_shadowlocal(m5)
2573 wg_probe(m5, STAGE_VERTEX, "shadowlocal" as *u8, 1, tr, tn)
2574 // NEG-CONTROL S2b -- a PARAMETER named like a uniform is read bare
2575 let m6: *i64 = sir_new()
2576 shsrc_plain_shadowparam(m6)
2577 wg_probe(m6, STAGE_PLAIN, "shadowparam" as *u8, 1, tr, tn)
2578 // S3 COVERAGE -- K_TEXTURE through BOTH backends: binding var OUTSIDE struct U / sampler uniform, trace-identical
2579 let m7: *i64 = sir_new()
2580 shsrc_tex_plain(m7)
2581 let gt7: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2582 let gn7: *i64 = sys_mmap(WG_NUMBUF) as *i64
2583 wg_probe(m7, STAGE_PLAIN, "tex_glsl" as *u8, 0, gt7, gn7)
2584 wg_probe(m7, STAGE_PLAIN, "tex_wgsl" as *u8, 1, tr, tn)
2585 wg_puts("tex_trace_equal=" as *u8)
2586 q = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt7, gn7[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2587 wg_puts("\n" as *u8)
2588 // GE54 tex2d_sample: a sampled texture_2d<f32> emits in BOTH dialects (GLSL sampler2D, WGSL texture + companion sampler)
2589 let m11: *i64 = sir_new()
2590 shsrc_tex2d_sample(m11)
2591 let gt11: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2592 let gn11: *i64 = sys_mmap(WG_NUMBUF) as *i64
2593 wg_probe(m11, STAGE_PLAIN, "tex2dsmp_glsl" as *u8, 0, gt11, gn11)
2594 wg_probe(m11, STAGE_PLAIN, "tex2dsmp_wgsl" as *u8, 1, tr, tn)
2595 wg_puts("tex2dsmp_trace_equal=" as *u8)
2596 q = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt11, gn11[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2597 wg_puts("\n" as *u8)
2598 // GE55 K_PRIVATE -- module-scope private state through BOTH backends: var<private> / bare global, written by one
2599 // function and read bare by another, NEVER qualified as u.<name>, trace-identical across dialects.
2600 let m8: *i64 = sir_new()
2601 shsrc_private_demo(m8)
2602 let gt8: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2603 let gn8: *i64 = sys_mmap(WG_NUMBUF) as *i64
2604 wg_probe(m8, STAGE_PLAIN, "priv_glsl" as *u8, 0, gt8, gn8)
2605 wg_probe(m8, STAGE_PLAIN, "priv_wgsl" as *u8, 1, tr, tn)
2606 wg_puts("priv_trace_equal=" as *u8)
2607 q = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt8, gn8[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2608 wg_puts("\n" as *u8)
2609 // NEG-CONTROL -- a texture-typed private must refuse BY NAME in each dialect (module state is never a resource)
2610 let m9: *i64 = sir_new()
2611 sir_private(m9, "tp" as *u8, T_TEX3U, 0)
2612 shsrc_fullscreen_tri(m9)
2613 wg_probe(m9, STAGE_VERTEX, "privtex_glsl" as *u8, 0, gt8, gn8)
2614 let m10: *i64 = sir_new()
2615 sir_private(m10, "tp" as *u8, T_TEX3U, 0)
2616 shsrc_fullscreen_tri(m10)
2617 wg_probe(m10, STAGE_VERTEX, "privtex_wgsl" as *u8, 1, tr, tn)
2618 // NEG-CONTROL S3a -- a texture type outside the covered subset refuses BY NAME in BOTH dialects
2619 let m8: *i64 = sir_new()
2620 sir_texture(m8, "img" as *u8, T_TEX2F)
2621 shsrc_frag_const(m8)
2622 wg_probe(m8, STAGE_FRAGMENT, "tex2d_wgsl" as *u8, 1, tr, tn)
2623 let m9: *i64 = sir_new()
2624 sir_texture(m9, "img" as *u8, T_TEX2F)
2625 shsrc_frag_const(m9)
2626 wg_probe(m9, STAGE_FRAGMENT, "tex2d_glsl" as *u8, 0, tr, tn)
2627 // NEG-CONTROL S3b -- the deprecated form (a texture-typed K_UNIFORM) refuses in GLSL too, naming K_TEXTURE
2628 let m10: *i64 = sir_new()
2629 sir_uniform(m10, "vox" as *u8, T_TEX3U, 0)
2630 shsrc_fullscreen_tri(m10)
2631 wg_probe(m10, STAGE_VERTEX, "texuniform_glsl" as *u8, 0, tr, tn)
2632 // NEG-CONTROL S3c -- a derived texture binding landing on an explicit storage binding refuses by name
2633 let m11: *i64 = sir_new()
2634 shsrc_depth_min(m11)
2635 sir_texture(m11, "vox" as *u8, T_TEX3U)
2636 wg_probe(m11, STAGE_COMPUTE, "texcollide" as *u8, 1, tr, tn)
2637 // S4 COVERAGE -- the fragment entry signature is DERIVED from the declared position parameter, both dialects
2638 let m12: *i64 = sir_new()
2639 shsrc_frag_pos(m12)
2640 let gt12: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2641 let gn12: *i64 = sys_mmap(WG_NUMBUF) as *i64
2642 wg_probe(m12, STAGE_FRAGMENT, "fragpos_glsl" as *u8, 0, gt12, gn12)
2643 wg_probe(m12, STAGE_FRAGMENT, "fragpos_wgsl" as *u8, 1, tr, tn)
2644 wg_puts("fragpos_trace_equal=" as *u8)
2645 q = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt12, gn12[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2646 wg_puts("\n" as *u8)
2647 // CONTROL S4 -- the zero-parameter fragment derives to exactly the signature the literal used to carry
2648 let m13: *i64 = sir_new()
2649 shsrc_frag_const(m13)
2650 wg_probe(m13, STAGE_FRAGMENT, "fragconst" as *u8, 1, tr, tn)
2651 // NEG-CONTROL S4a -- reading position with NO declared parameter is an undeclared input: refused by name
2652 let m14: *i64 = sir_new()
2653 shsrc_frag_pos_undeclared(m14)
2654 wg_probe(m14, STAGE_FRAGMENT, "fragundecl" as *u8, 1, tr, tn)
2655 // NEG-CONTROL S4b -- a plain (unbound) fragment parameter refuses by name in BOTH dialects
2656 let m15: *i64 = sir_new()
2657 shsrc_frag_plainparam(m15)
2658 wg_probe(m15, STAGE_FRAGMENT, "fragplain_wgsl" as *u8, 1, tr, tn)
2659 let m16: *i64 = sir_new()
2660 shsrc_frag_plainparam(m16)
2661 wg_probe(m16, STAGE_FRAGMENT, "fragplain_glsl" as *u8, 0, tr, tn)
2662 // S5 COVERAGE -- the declared fragment output through BOTH backends, trace-identical: GLSL declares
2663 // `out vec4 fc;` and ASSIGNS it, WGSL declares nothing and DERIVES `->@location(0) vec4f`.
2664 let m17: *i64 = sir_new()
2665 shsrc_frag_const(m17)
2666 let gt17: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2667 let gn17: *i64 = sys_mmap(WG_NUMBUF) as *i64
2668 wg_probe(m17, STAGE_FRAGMENT, "fragout_glsl" as *u8, 0, gt17, gn17)
2669 wg_probe(m17, STAGE_FRAGMENT, "fragout_wgsl" as *u8, 1, tr, tn)
2670 wg_puts("fragout_trace_equal=" as *u8)
2671 q = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt17, gn17[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2672 wg_puts("\n" as *u8)
2673 // S5 POSITIVE CONTROL -- a discard-only fragment declares NO output and BOTH backends admit it. Without
2674 // this the output rule would be a guard that refuses a legal program and nobody would have measured it.
2675 let m18: *i64 = sir_new()
2676 shsrc_frag_discard(m18)
2677 wg_probe(m18, STAGE_FRAGMENT, "fragdiscard_glsl" as *u8, 0, tr, tn)
2678 let m19: *i64 = sir_new()
2679 shsrc_frag_discard(m19)
2680 wg_probe(m19, STAGE_FRAGMENT, "fragdiscard_wgsl" as *u8, 1, tr, tn)
2681 // S5 NEG-CONTROL -- returning a value with no declared output refuses BY NAME in both dialects
2682 let m20: *i64 = sir_new()
2683 shsrc_frag_noout(m20)
2684 wg_probe(m20, STAGE_FRAGMENT, "fragnoout_glsl" as *u8, 0, tr, tn)
2685 let m21: *i64 = sir_new()
2686 shsrc_frag_noout(m21)
2687 wg_probe(m21, STAGE_FRAGMENT, "fragnoout_wgsl" as *u8, 1, tr, tn)
2688 // S5 COVERAGE -- a NON-ZERO @location proves the location is data, not the constant 0
2689 let m22: *i64 = sir_new()
2690 shsrc_frag_loc2(m22)
2691 wg_probe(m22, STAGE_FRAGMENT, "fragloc2_glsl" as *u8, 0, tr, tn)
2692 let m23: *i64 = sir_new()
2693 shsrc_frag_loc2(m23)
2694 wg_probe(m23, STAGE_FRAGMENT, "fragloc2_wgsl" as *u8, 1, tr, tn)
2695 // S5 NEG-CONTROL -- a fragment output on a VERTEX stage refuses by name in both dialects
2696 let m24: *i64 = sir_new()
2697 shsrc_vert_fragout(m24)
2698 wg_probe(m24, STAGE_VERTEX, "vertfragout_glsl" as *u8, 0, tr, tn)
2699 let m25: *i64 = sir_new()
2700 shsrc_vert_fragout(m25)
2701 wg_probe(m25, STAGE_VERTEX, "vertfragout_wgsl" as *u8, 1, tr, tn)
2702 // S5 NEG-CONTROL -- two declared outputs (MRT) refuse by name rather than dropping one
2703 let m26: *i64 = sir_new()
2704 shsrc_frag_twoout(m26)
2705 wg_probe(m26, STAGE_FRAGMENT, "fragtwoout_glsl" as *u8, 0, tr, tn)
2706 let m27: *i64 = sir_new()
2707 shsrc_frag_twoout(m27)
2708 wg_probe(m27, STAGE_FRAGMENT, "fragtwoout_wgsl" as *u8, 1, tr, tn)
2709 // S5 NEG-CONTROL -- a sampled texture read refuses in WGSL (undeclared sampler) and EMITS in GLSL.
2710 // Both halves are asserted: a refusal with no admitting twin would not prove the rule is the sampler.
2711 let m28: *i64 = sir_new()
2712 shsrc_texsample(m28)
2713 wg_probe(m28, STAGE_PLAIN, "texsample_wgsl" as *u8, 1, tr, tn)
2714 let m29: *i64 = sir_new()
2715 shsrc_texsample(m29)
2716 wg_probe(m29, STAGE_PLAIN, "texsample_glsl" as *u8, 0, tr, tn)
2717 // R-A / R-C COVERAGE (2026-09-04, GE44 R-A and R-C): a select and an immutable local through BOTH backends,
2718 // trace-identical -- the ternary in GLSL, select(f,t,cond) and `let` in WGSL.
2719 let m30: *i64 = sir_new()
2720 shsrc_select_let(m30)
2721 let gt30: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2722 let gn30: *i64 = sys_mmap(WG_NUMBUF) as *i64
2723 wg_probe(m30, STAGE_PLAIN, "selectlet_glsl" as *u8, 0, gt30, gn30)
2724 wg_probe(m30, STAGE_PLAIN, "selectlet_wgsl" as *u8, 1, tr, tn)
2725 wg_puts("selectlet_trace_equal=" as *u8)
2726 q = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt30, gn30[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2727 wg_puts("\n" as *u8)
2728 // R-B COVERAGE (2026-09-04, GE44 R-B): a counted loop written ONCE as builder sugar (sir_for_until), through
2729 // BOTH backends, trace-identical -- while(true) in GLSL, loop in WGSL, the exit test and the step in the
2730 // shared S_IF/S_LOOP/S_ASSIGN arms, the counter a mutable local in each dialect's own spelling.
2731 let m31: *i64 = sir_new()
2732 shsrc_for_until(m31)
2733 let gt31: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2734 let gn31: *i64 = sys_mmap(WG_NUMBUF) as *i64
2735 wg_probe(m31, STAGE_PLAIN, "foruntil_glsl" as *u8, 0, gt31, gn31)
2736 wg_probe(m31, STAGE_PLAIN, "foruntil_wgsl" as *u8, 1, tr, tn)
2737 wg_puts("foruntil_trace_equal=" as *u8)
2738 q = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt31, gn31[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2739 wg_puts("\n" as *u8)
2740 // R-D COVERAGE (2026-09-04, GE44 R-D): a struct declared once, a struct-typed local built by its constructor,
2741 // a member write and member reads, through BOTH backends, trace-identical -- `struct Hit{vec3 pos;float d;};`
2742 // in GLSL, `struct Hit{pos:vec3f,d:f32,}` in WGSL, `h.d` and `h.pos.x` spelled the same in both.
2743 let m32: *i64 = sir_new()
2744 shsrc_struct(m32)
2745 let gt32: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2746 let gn32: *i64 = sys_mmap(WG_NUMBUF) as *i64
2747 wg_probe(m32, STAGE_PLAIN, "struct_glsl" as *u8, 0, gt32, gn32)
2748 wg_probe(m32, STAGE_PLAIN, "struct_wgsl" as *u8, 1, tr, tn)
2749 wg_puts("struct_trace_equal=" as *u8)
2750 q = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt32, gn32[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2751 wg_puts("\n" as *u8)
2752 // R-E COVERAGE (2026-09-04, GE44 R-E): a struct RETURN and a struct PARAMETER through BOTH backends, one
2753 // canonical shape, trace-identical -- `Hit mk(vec3 p,float k)` / `fn mk(p:vec3f,k:f32)->Hit`, and a member
2754 // read straight off the call (`mk(h.pos,k).d`) spelled the same in both.
2755 let m33: *i64 = sir_new()
2756 shsrc_struct_ret(m33)
2757 let gt33: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2758 let gn33: *i64 = sys_mmap(WG_NUMBUF) as *i64
2759 wg_probe(m33, STAGE_PLAIN, "structret_glsl" as *u8, 0, gt33, gn33)
2760 wg_probe(m33, STAGE_PLAIN, "structret_wgsl" as *u8, 1, tr, tn)
2761 wg_puts("structret_trace_equal=" as *u8)
2762 q = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt33, gn33[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2763 wg_puts("\n" as *u8)
2764 // R-G0 COVERAGE (2026-09-04, GE44 R-G0): an uninitialised local and a unary negation through BOTH backends,
2765 // trace-identical -- `float v;` / `var v:f32;` and `v=(-a);` spelled the same in both.
2766 let m34: *i64 = sir_new()
2767 shsrc_neg_uninit(m34)
2768 let gt34: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
2769 let gn34: *i64 = sys_mmap(WG_NUMBUF) as *i64
2770 wg_probe(m34, STAGE_PLAIN, "neguninit_glsl" as *u8, 0, gt34, gn34)
2771 wg_probe(m34, STAGE_PLAIN, "neguninit_wgsl" as *u8, 1, tr, tn)
2772 wg_puts("neguninit_trace_equal=" as *u8)
2773 q = eb_num(nb, 0, WG_NUMBUF, wg_trace_eq(gt34, gn34[0], tr, tn[0])); nb[q] = 0 as u8; wg_puts(nb)
2774 wg_puts("\n" as *u8)
2775 return 0
2776}
2777
2778// ============================ RUNG 2: THE FRONT HALF ============================
2779// Lower an nx_ir SSA Function -- produced by the REAL lexer/parser/optimiser -- into the shader
2780// IR, so a shader is an ORDINARY NISHILANG FUNCTION rather than builder calls. Straight-line
2781// functions only: GLSL and WGSL have no goto, so a multi-block CFG needs structured control-flow
2782// recovery (the problem WebAssembly had to solve). That is REFUSED BY NAME here, not guessed.
2783
2784// Driver buffers, named for purpose (the magic ratchet refused inline literals and was right).
2785const SHL_EXPAND_CAP: i64 = 4194304
2786const SHL_LEX_CAP: i64 = 262144
2787
2788// nx_ir Type kind -> shader type. i64/f64/pointer/struct have NO GLSL ES 3.00 counterpart, so
2789// they REFUSE rather than narrow: silently turning an i64 into an int is precisely the
2790// mistranslation this backend exists to make impossible.
2791func shl_ty(t: *Type) -> i64 {
2792 if (t as i64) == 0 { return T_VOID }
2793 let k: i64 = t.kind
2794 if k == 0 { return T_VOID }
2795 if k == 1 { return T_BOOL }
2796 if k == 4 { return T_I32 }
2797 if k == 9 { return T_F32 }
2798 return 0 - 1
2799}
2800
2801func shl_op(op: i64) -> *u8 {
2802 if op == OP_ADD { return "+" as *u8 }
2803 if op == OP_SUB { return "-" as *u8 }
2804 if op == OP_MUL { return "*" as *u8 }
2805 if op == OP_DIV_S { return "/" as *u8 }
2806 if op == OP_AND { return "&" as *u8 }
2807 if op == OP_OR { return "|" as *u8 }
2808 if op == OP_XOR { return "^" as *u8 }
2809 if op == OP_SHL { return "<<" as *u8 }
2810 if op == OP_SHR_S { return ">>" as *u8 }
2811 if op == OP_EQ { return "==" as *u8 }
2812 if op == OP_NE { return "!=" as *u8 }
2813 if op == OP_LT_S { return "<" as *u8 }
2814 if op == OP_LE_S { return "<=" as *u8 }
2815 if op == OP_GT_S { return ">" as *u8 }
2816 if op == OP_GE_S { return ">=" as *u8 }
2817 return 0 as *u8
2818}
2819
2820// An SSA operand becomes: a literal (CONST_INT), a parameter name (PARAM), or the named
2821// temporary emitted for the instruction that defined it (INSTR). No expression-tree rebuild is
2822// needed -- one named temporary per instruction is the classic SSA-to-text lowering, and it is
2823// exactly why the straight-line case needs no relooper.
2824func shl_val(m2: *i64, f: *Function, vid: i64, nb: *u8) -> i64 {
2825 let v: *Value = val_at(f, vid)
2826 if (v as i64) == 0 { return 0 }
2827 let ty: i64 = shl_ty(v.ty)
2828 var q: i64 = 0
2829 if v.kind == 0 {
2830 q = eb_num(nb, 0, WG_NUMBUF, v.const_int)
2831 nb[q] = 0 as u8
2832 return sir_lit(m2, nb, ty)
2833 }
2834 if v.kind == 1 {
2835 q = eb_put(nb, 0, WG_NUMBUF, "p" as *u8)
2836 q = eb_num(nb, q, WG_NUMBUF, v.param_index)
2837 nb[q] = 0 as u8
2838 return sir_ident(m2, nb, ty)
2839 }
2840 q = eb_put(nb, 0, WG_NUMBUF, "t" as *u8)
2841 q = eb_num(nb, q, WG_NUMBUF, vid)
2842 nb[q] = 0 as u8
2843 return sir_ident(m2, nb, ty)
2844}
2845
2846// Lower ONE basic block. Statements are appended to fn2 and then DETACHED as a standalone chain,
2847// so the caller can place them inside an if-branch instead of at function top level. Terminators
2848// (BR / BR_COND) emit NOTHING here: control flow is the SHAPE recogniser's job, and a terminator
2849// that leaked through as a statement would be a goto in a language that has none.
2850func shl_blk(m2: *i64, f: *Function, fn2: i64, bb: *BasicBlock, nb: *u8, msg: *u8, seen: *i64) -> i64 {
2851 if (bb as i64) == 0 { sir_refuse(m2, "basic block is absent" as *u8); return 0 - 1 }
2852 let t0: i64 = sir_get(m2, fn2, SIR_D)
2853 var ins: *Instr = bb.head
2854 while (ins as i64) != 0 {
2855 let op: i64 = ins.op
2856 if op == OP_BR { } else { if op == OP_BR_COND { } else {
2857 if op == OP_RETURN {
2858 var e: i64 = 0
2859 if ins.n_operands > 0 { e = shl_val(m2, f, ins.op0, nb) }
2860 sir_stmt(m2, fn2, sir_return(m2, e))
2861 } else { if op == OP_ALLOCA {
2862 // DELIBERATELY NO EMISSION -- see shl_lower.
2863 } else { if op == OP_STORE {
2864 let ad: i64 = ins.op0
2865 let vx: i64 = shl_val(m2, f, ins.op1, nb)
2866 let vv: *Value = val_at(f, ins.op1)
2867 var vt: i64 = 0 - 1
2868 if (vv as i64) != 0 { vt = shl_ty(vv.ty) }
2869 if vt < 0 { sir_refuse(m2, "stored value type has no GLSL ES 3.00 counterpart -- refused rather than narrowed" as *u8); return 0 - 1 }
2870 var qa: i64 = eb_put(nb, 0, WG_NUMBUF, "a" as *u8)
2871 qa = eb_num(nb, qa, WG_NUMBUF, ad)
2872 nb[qa] = 0 as u8
2873 if seen[ad] == 0 {
2874 seen[ad] = 1
2875 sir_stmt(m2, fn2, sir_var(m2, nb, vt, vx))
2876 } else {
2877 sir_stmt(m2, fn2, sir_assign(m2, sir_ident(m2, nb, vt), vx))
2878 }
2879 } else { if op == OP_LOAD {
2880 let ad2: i64 = ins.op0
2881 let lt2: i64 = shl_ty(ins.ty)
2882 if lt2 < 0 { sir_refuse(m2, "loaded value type has no GLSL ES 3.00 counterpart -- refused rather than narrowed" as *u8); return 0 - 1 }
2883 var qb: i64 = eb_put(nb, 0, WG_NUMBUF, "a" as *u8)
2884 qb = eb_num(nb, qb, WG_NUMBUF, ad2)
2885 nb[qb] = 0 as u8
2886 let srcv: i64 = sir_ident(m2, nb, lt2)
2887 var qc: i64 = eb_put(nb, 0, WG_NUMBUF, "t" as *u8)
2888 qc = eb_num(nb, qc, WG_NUMBUF, ins.result)
2889 nb[qc] = 0 as u8
2890 sir_stmt(m2, fn2, sir_var(m2, nb, lt2, srcv))
2891 } else {
2892 let ops: *u8 = shl_op(op)
2893 if (ops as i64) == 0 {
2894 var qm: i64 = eb_put(msg, 0, WG_MSGBUF, "opcode outside the covered subset: op=" as *u8)
2895 qm = eb_num(msg, qm, WG_MSGBUF, op)
2896 msg[qm] = 0 as u8
2897 sir_refuse(m2, msg)
2898 return 0 - 1
2899 }
2900 let lt: i64 = shl_ty(ins.ty)
2901 if lt < 0 { sir_refuse(m2, "instruction result type has no GLSL ES 3.00 counterpart -- refused rather than narrowed" as *u8); return 0 - 1 }
2902 let l: i64 = shl_val(m2, f, ins.op0, nb)
2903 let r: i64 = shl_val(m2, f, ins.op1, nb)
2904 let bx: i64 = sir_bin(m2, ops, l, r, lt)
2905 var qt: i64 = eb_put(nb, 0, WG_NUMBUF, "t" as *u8)
2906 qt = eb_num(nb, qt, WG_NUMBUF, ins.result)
2907 nb[qt] = 0 as u8
2908 sir_stmt(m2, fn2, sir_var(m2, nb, lt, bx))
2909 } } } } } }
2910 ins = ins.next
2911 }
2912 var head: i64 = 0
2913 if t0 == 0 {
2914 head = sir_get(m2, fn2, SIR_B)
2915 sir_set(m2, fn2, SIR_B, 0)
2916 sir_set(m2, fn2, SIR_D, 0)
2917 } else {
2918 head = sir_get(m2, t0, SIR_NEXT)
2919 sir_set(m2, t0, SIR_NEXT, 0)
2920 sir_set(m2, fn2, SIR_D, t0)
2921 }
2922 return head
2923}
2924
2925// ---- RUNG 2b-GENERAL: recursive region reduction ------------------------------------------
2926// block_at() takes an INDEX; the CFG talks in IDs. Resolve rather than assume they coincide.
2927func shl_bid(f: *Function, id: i64) -> *BasicBlock {
2928 var i: i64 = 0
2929 while i < f.n_blocks {
2930 let b: *BasicBlock = block_at(f, i)
2931 if (b as i64) != 0 { if b.id == id { return b } }
2932 i = i + 1
2933 }
2934 return 0 as *BasicBlock
2935}
2936
2937// Can control reach `to` starting at `from`? Breadth-first over successors. This is the ONLY
2938// back-edge test used below: a heuristic on block ORDER would silently mis-shape any CFG whose
2939// numbering is not the traversal order, and the whole point of this rung is to stop guessing.
2940func shl_reaches(f: *Function, from: i64, to: i64, mark: *i64, wl: *i64) -> i64 {
2941 if from < 0 { return 0 }
2942 var i: i64 = 0
2943 while i < f.n_blocks { mark[i] = 0; i = i + 1 }
2944 var wn: i64 = 0
2945 var wp: i64 = 0
2946 if from < f.n_blocks { mark[from] = 1 }
2947 wl[wn] = from
2948 wn = wn + 1
2949 while wp < wn {
2950 let cid: i64 = wl[wp]
2951 wp = wp + 1
2952 if cid == to { return 1 }
2953 let b: *BasicBlock = shl_bid(f, cid)
2954 if (b as i64) != 0 {
2955 if b.n_succs > 0 { if (b.succ0 as i64) != 0 {
2956 let s: i64 = b.succ0.id
2957 if s >= 0 { if s < f.n_blocks { if mark[s] == 0 { mark[s] = 1; wl[wn] = s; wn = wn + 1 } } }
2958 } }
2959 if b.n_succs > 1 { if (b.succ1 as i64) != 0 {
2960 let s2: i64 = b.succ1.id
2961 if s2 >= 0 { if s2 < f.n_blocks { if mark[s2] == 0 { mark[s2] = 1; wl[wn] = s2; wn = wn + 1 } } }
2962 } }
2963 }
2964 }
2965 return 0
2966}
2967
2968// Reachability that must not pass THROUGH `avoid`. This is the whole dominance test: B dominates
2969// P exactly when P cannot be reached from the entry without going through B.
2970func shl_reaches_avoid(f: *Function, from: i64, to: i64, avoid: i64, mark: *i64, wl: *i64) -> i64 {
2971 if from < 0 { return 0 }
2972 if from == avoid { return 0 }
2973 var i: i64 = 0
2974 while i < f.n_blocks { mark[i] = 0; i = i + 1 }
2975 var wn: i64 = 0
2976 var wp: i64 = 0
2977 if from < f.n_blocks { mark[from] = 1 }
2978 wl[wn] = from
2979 wn = wn + 1
2980 while wp < wn {
2981 let cid: i64 = wl[wp]
2982 wp = wp + 1
2983 if cid == to { return 1 }
2984 let b: *BasicBlock = shl_bid(f, cid)
2985 if (b as i64) != 0 {
2986 if b.n_succs > 0 { if (b.succ0 as i64) != 0 {
2987 let s: i64 = b.succ0.id
2988 if s != avoid { if s >= 0 { if s < f.n_blocks { if mark[s] == 0 { mark[s] = 1; wl[wn] = s; wn = wn + 1 } } } }
2989 } }
2990 if b.n_succs > 1 { if (b.succ1 as i64) != 0 {
2991 let s2: i64 = b.succ1.id
2992 if s2 != avoid { if s2 >= 0 { if s2 < f.n_blocks { if mark[s2] == 0 { mark[s2] = 1; wl[wn] = s2; wn = wn + 1 } } } }
2993 } }
2994 }
2995 }
2996 return 0
2997}
2998
2999func shl_dominates(f: *Function, b: i64, p: i64, mark: *i64, wl: *i64) -> i64 {
3000 if b == p { return 1 }
3001 if (f.entry as i64) == 0 { return 0 }
3002 if shl_reaches_avoid(f, f.entry.id, p, b, mark, wl) == 1 { return 0 }
3003 return 1
3004}
3005
3006// A block is a loop HEADER iff some edge P -> bb is a BACK EDGE, i.e. bb DOMINATES P.
3007//
3008// THE OBVIOUS PREDICATE IS WRONG AND THIS LANE SHIPPED IT ONCE: "can one of my successors reach me
3009// again" is true of EVERY block in a cycle, not just its header, so it flagged the latch as a
3010// header and refused a textbook while-loop for having n_preds=1. It was caught because the refusal
3011// CONTRADICTED THE CFG DUMP PRINTED DIRECTLY ABOVE IT -- the message said n_preds != 2 about a
3012// block the dump showed with preds=2, which can only mean the predicate had selected a different
3013// block. A refusal that names its numbers is what made a wrong predicate visible in one run.
3014func shl_is_header(f: *Function, bb: *BasicBlock, mark: *i64, wl: *i64) -> i64 {
3015 var i: i64 = 0
3016 while i < f.n_blocks {
3017 let p: *BasicBlock = block_at(f, i)
3018 if (p as i64) != 0 {
3019 var edge: i64 = 0
3020 if p.n_succs > 0 { if (p.succ0 as i64) != 0 { if p.succ0.id == bb.id { edge = 1 } } }
3021 if p.n_succs > 1 { if (p.succ1 as i64) != 0 { if p.succ1.id == bb.id { edge = 1 } } }
3022 if edge == 1 { if shl_dominates(f, bb.id, p.id, mark, wl) == 1 { return 1 } }
3023 }
3024 i = i + 1
3025 }
3026 return 0
3027}
3028
3029// Lower the region that begins at block `eid` and ends when control reaches `stop` (a block id,
3030// or -1 for "run to the end of the function"). Returns a statement chain, or -1 having NAMED the
3031// refusal. This is the Relooper's shape trichotomy -- Simple / Loop / Multiple -- restricted to
3032// the single-entry reducible case that MEASUREMENT showed our front-end actually emits, and
3033// refusing everything else by name instead of guessing at it.
3034//
3035// WHY NO LABEL VARIABLE, AND WHY NO NODE DUPLICATION. The Relooper needs both because it accepts
3036// arbitrary CFGs: its label variable exists to re-enter the right block of a MULTI-ENTRY region.
3037// Every loop header in our measured corpus has exactly TWO predecessors -- one preheader, one
3038// latch -- so there is no multi-entry region for a label variable to disambiguate. LLVM's
3039// WebAssembly Stackifier states the same precondition in its own header comment: its marker
3040// insertion "is sufficient to convert arbitrary CFGs into a form that works on WebAssembly,
3041// provided that all loops are single-entry" (read from the mirrored source, key llvm-cfgstackify).
3042// The moment a header appears with n_preds != 2 this refuses BY NAME rather than mis-shaping it.
3043func shl_region(m2: *i64, f: *Function, fn2: i64, eid: i64, stop: i64, nb: *u8, msg: *u8, seen: *i64, mark: *i64, wl: *i64, depth: i64) -> i64 {
3044 if depth > f.n_blocks { sir_refuse(m2, "region nesting deeper than the block count -- the CFG is not the reducible shape this reducer accepts" as *u8); return 0 - 1 }
3045 var chain: i64 = 0
3046 var cur: i64 = eid
3047 var step: i64 = 0
3048 let maxstep: i64 = f.n_blocks + 1
3049 while step < maxstep {
3050 step = step + 1
3051 if cur < 0 { return chain }
3052 if cur == stop { return chain }
3053 let bb: *BasicBlock = shl_bid(f, cur)
3054 if (bb as i64) == 0 { sir_refuse(m2, "region walk reached a block id with no block" as *u8); return 0 - 1 }
3055
3056 if shl_is_header(f, bb, mark, wl) == 1 {
3057 if bb.n_preds != 2 { sir_refuse(m2, "loop header with n_preds != 2: a MULTI-ENTRY or multi-latch loop needs the Relooper's label variable or node duplication -- rung 2b-irreducible, refused rather than guessed" as *u8); return 0 - 1 }
3058 if bb.n_succs != 2 { sir_refuse(m2, "loop header without a two-way exit test -- a loop with no break has no terminating shader meaning" as *u8); return 0 - 1 }
3059 if (bb.succ0 as i64) == 0 { sir_refuse(m2, "loop header succ0 missing" as *u8); return 0 - 1 }
3060 if (bb.succ1 as i64) == 0 { sir_refuse(m2, "loop header succ1 missing" as *u8); return 0 - 1 }
3061 let s0: i64 = bb.succ0.id
3062 let s1: i64 = bb.succ1.id
3063 var body0: i64 = 0 - 1
3064 var exitb: i64 = 0 - 1
3065 var thenisbody: i64 = 0
3066 if shl_reaches(f, s0, bb.id, mark, wl) == 1 { body0 = s0; exitb = s1; thenisbody = 1 }
3067 if body0 < 0 { if shl_reaches(f, s1, bb.id, mark, wl) == 1 { body0 = s1; exitb = s0; thenisbody = 0 } }
3068 if body0 < 0 { sir_refuse(m2, "loop header has a back edge but neither successor re-reaches it" as *u8); return 0 - 1 }
3069 var cnd: i64 = 0
3070 var tm: *Instr = bb.head
3071 while (tm as i64) != 0 {
3072 if tm.op == OP_BR_COND { cnd = shl_val(m2, f, tm.op0, nb) }
3073 tm = tm.next
3074 }
3075 if cnd == 0 { sir_refuse(m2, "loop header carries no BR_COND condition operand" as *u8); return 0 - 1 }
3076 // The header's own straight-line code is the loop TEST and must be re-evaluated every
3077 // iteration, so it is emitted INSIDE the loop, above the break.
3078 let hc: i64 = shl_blk(m2, f, fn2, bb, nb, msg, seen)
3079 if hc == (0 - 1) { return 0 - 1 }
3080 let bc: i64 = shl_region(m2, f, fn2, body0, bb.id, nb, msg, seen, mark, wl, depth + 1)
3081 if bc == (0 - 1) { return 0 - 1 }
3082 let brk: i64 = sir_break(m2)
3083 // No NOT node is invented: the two polarities are expressed by which ARM carries the
3084 // break, so an inverted test can never be silently emitted as an un-inverted one.
3085 var ifs: i64 = 0
3086 if thenisbody == 1 { ifs = sir_if(m2, cnd, bc, brk) }
3087 if thenisbody == 0 { ifs = sir_if(m2, cnd, brk, bc) }
3088 let lbody: i64 = sir_seq(m2, hc, ifs)
3089 let lp: i64 = sir_loop(m2, lbody)
3090 chain = sir_seq(m2, chain, lp)
3091 cur = exitb
3092 }
3093 if shl_is_header(f, bb, mark, wl) == 0 {
3094 if bb.n_succs == 0 {
3095 let tc0: i64 = shl_blk(m2, f, fn2, bb, nb, msg, seen)
3096 if tc0 == (0 - 1) { return 0 - 1 }
3097 return sir_seq(m2, chain, tc0)
3098 }
3099 if bb.n_succs == 1 {
3100 let sc: i64 = shl_blk(m2, f, fn2, bb, nb, msg, seen)
3101 if sc == (0 - 1) { return 0 - 1 }
3102 chain = sir_seq(m2, chain, sc)
3103 if (bb.succ0 as i64) == 0 { sir_refuse(m2, "single-successor block with a null successor" as *u8); return 0 - 1 }
3104 cur = bb.succ0.id
3105 }
3106 if bb.n_succs == 2 {
3107 if (bb.succ0 as i64) == 0 { sir_refuse(m2, "two-way block succ0 missing" as *u8); return 0 - 1 }
3108 if (bb.succ1 as i64) == 0 { sir_refuse(m2, "two-way block succ1 missing" as *u8); return 0 - 1 }
3109 let tb2: *BasicBlock = bb.succ0
3110 let jb2: *BasicBlock = bb.succ1
3111 // SHAPE A -- if WITHOUT else: the then-arm falls through to the OTHER successor,
3112 // so that other successor IS the join and there are three blocks in play.
3113 var ok2: i64 = 0
3114 // SHAPE B -- if/ELSE: BOTH arms fall through to a common THIRD block. Four blocks.
3115 // This shape was found by its own negative control (knowledge/nxsh_ifelse.nx),
3116 // which refused by name and thereby named the gap: shaders use else constantly.
3117 var okelse: i64 = 0
3118 var joinid: i64 = 0 - 1
3119 if tb2.n_succs == 1 { if (tb2.succ0 as i64) != 0 {
3120 if tb2.succ0.id == jb2.id { if jb2.n_preds == 2 { ok2 = 1; joinid = jb2.id } }
3121 } }
3122 if ok2 == 0 { if tb2.n_succs == 1 { if jb2.n_succs == 1 {
3123 if (tb2.succ0 as i64) != 0 { if (jb2.succ0 as i64) != 0 {
3124 if tb2.succ0.id == jb2.succ0.id {
3125 if tb2.succ0.n_preds == 2 { okelse = 1; joinid = tb2.succ0.id }
3126 }
3127 } }
3128 } } }
3129 if ok2 == 0 { if okelse == 0 { sir_refuse(m2, "two-way branch that is neither an if-diamond (then-arm falls through to the other successor) nor an if/else (both arms fall through to one common join whose only predecessors are those two arms) -- rung 2b-irreducible" as *u8); return 0 - 1 } }
3130 var cnd2: i64 = 0
3131 var tm2: *Instr = bb.head
3132 while (tm2 as i64) != 0 {
3133 if tm2.op == OP_BR_COND { cnd2 = shl_val(m2, f, tm2.op0, nb) }
3134 tm2 = tm2.next
3135 }
3136 if cnd2 == 0 { sir_refuse(m2, "if-diamond header carries no BR_COND condition operand" as *u8); return 0 - 1 }
3137 let hc2: i64 = shl_blk(m2, f, fn2, bb, nb, msg, seen)
3138 if hc2 == (0 - 1) { return 0 - 1 }
3139 let tc2: i64 = shl_region(m2, f, fn2, tb2.id, joinid, nb, msg, seen, mark, wl, depth + 1)
3140 if tc2 == (0 - 1) { return 0 - 1 }
3141 // The else arm is a REGION too, so an else containing a loop, or a nested if, or
3142 // anything else the reducer knows, composes for free. sir_if already carries an
3143 // else slot (SIR_C) and both emitters already render it: 0 means no else arm.
3144 var ec2: i64 = 0
3145 if okelse == 1 {
3146 ec2 = shl_region(m2, f, fn2, jb2.id, joinid, nb, msg, seen, mark, wl, depth + 1)
3147 if ec2 == (0 - 1) { return 0 - 1 }
3148 }
3149 chain = sir_seq(m2, chain, hc2)
3150 chain = sir_seq(m2, chain, sir_if(m2, cnd2, tc2, ec2))
3151 cur = joinid
3152 }
3153 if bb.n_succs > 2 { sir_refuse(m2, "block with more than two successors (a switch) -- the Relooper's Multiple block is rung 2b-multiple, not implemented, refused rather than guessed" as *u8); return 0 - 1 }
3154 }
3155 }
3156 sir_refuse(m2, "region walk exceeded its derived step budget (one visit per block) -- the CFG is not the reducible shape this reducer accepts" as *u8)
3157 return 0 - 1
3158}
3159
3160func shl_lower(m2: *i64, f: *Function, fname: *u8) -> i64 {
3161 let nb: *u8 = sys_mmap(WG_NUMBUF)
3162 let msg: *u8 = sys_mmap(WG_MSGBUF)
3163 // One flag per SSA value: has this alloca been stored to yet? The FIRST store declares the
3164 // shader local (with the stored value's type, which is where the type actually comes from --
3165 // an alloca's own type is a pointer, and a shader has no pointers); later stores assign to it.
3166 // sys_mmap zero-fills, so "not yet stored" needs no initialisation pass.
3167 let seen: *i64 = sys_mmap(f.n_values*8 + 8) as *i64
3168 let rt: i64 = shl_ty(f.ret_ty)
3169 if rt < 0 { sir_refuse(m2, "return type has no GLSL ES 3.00 counterpart (i64/f64/pointer) -- refused rather than narrowed" as *u8); return 0 - 1 }
3170 let fn2: i64 = sir_func(m2, fname, rt)
3171 var vi: i64 = 0
3172 while vi < f.n_values {
3173 let v: *Value = val_at(f, vi)
3174 if (v as i64) != 0 { if v.kind == 1 {
3175 let pt: i64 = shl_ty(v.ty)
3176 if pt < 0 { sir_refuse(m2, "parameter type has no GLSL ES 3.00 counterpart -- refused rather than narrowed" as *u8); return 0 - 1 }
3177 var q: i64 = eb_put(nb, 0, WG_NUMBUF, "p" as *u8)
3178 q = eb_num(nb, q, WG_NUMBUF, v.param_index)
3179 nb[q] = 0 as u8
3180 sir_param(m2, fn2, nb, pt)
3181 } }
3182 vi = vi + 1
3183 }
3184 let e0: *BasicBlock = f.entry
3185 if (e0 as i64) == 0 { sir_refuse(m2, "function has no entry block" as *u8); return 0 - 1 }
3186
3187 // ---- RUNG 2b-GENERAL: STRUCTURED CONTROL-FLOW RECOVERY, INCLUDING LOOPS --------------
3188 // GLSL and WGSL have no goto, so a CFG must be rebuilt into nested statements. This is the
3189 // problem WebAssembly had to solve for the same reason, and the field's answers are the
3190 // Relooper (Zakai, Emscripten, OOPSLA 2011) and LLVM's WebAssembly Stackifier, which reduce
3191 // a GENERAL CFG by duplicating nodes or dispatching on a state variable.
3192 //
3193 // THE REFS DEBT THIS COMMENT USED TO DECLARE IS PAID. Both are now fetched, mirrored and
3194 // hash-pinned in graphics.refs (keys relooper-zakai11, llvm-cfgstackify), and every phrase
3195 // quoted here came from bytes that were read, not recalled. Ramsey's ICFP 2022 "Beyond
3196 // Relooper" is deliberately NOT cited: dl.acm.org answered 403 with a 5,470-byte bot
3197 // challenge page on four attempts, so it was never read and must not be leaned on.
3198 //
3199 // WHY A SHAPE REDUCER IS SUFFICIENT HERE -- MEASURED, NOT ASSUMED. nx_parse keeps locals
3200 // ALLOCA-BACKED (proven when this backend first refused op=43) and the opcode table carries
3201 // NO PHI, so values crossing blocks -- including across a BACK EDGE -- travel through
3202 // memory. There are no phi nodes to place, and phi placement is the hard half of relooping.
3203 // The measured corpus knowledge/nxsh_{clip,branch,loop,skin,layers}.nx is 1/3/4/6/7 blocks,
3204 // covering straight-line, if-diamond, while, loop-containing-if and nested loops, and EVERY
3205 // loop header in it has exactly TWO predecessors: one preheader, one latch. Single-entry and
3206 // reducible throughout, with no multi-entry region anywhere. That is precisely the
3207 // Stackifier's own stated precondition -- its markers are "sufficient to convert arbitrary
3208 // CFGs into a form that works on WebAssembly, provided that all loops are single-entry".
3209 //
3210 // So the Relooper's label variable (which exists to re-enter the right block of a MULTI-entry
3211 // region) is not needed here, and neither is node duplication. Both remain the right answer
3212 // for the general case, and the moment a header appears with n_preds != 2, shl_region REFUSES
3213 // IT BY NAME rather than mis-shaping it into something that compiles and computes the wrong
3214 // thing. The straight-line and if-diamond special cases that used to sit here are gone: they
3215 // are shapes of the reducer now, not rivals to it.
3216 // ONE recursive region reducer owns every shape decision AND every refusal. There is no
3217 // second ruler here to drift out of agreement with it.
3218 let mark: *i64 = sys_mmap(f.n_blocks*8 + 64) as *i64
3219 let wlq: *i64 = sys_mmap(f.n_blocks*8 + 64) as *i64
3220 let rbody: i64 = shl_region(m2, f, fn2, e0.id, 0 - 1, nb, msg, seen, mark, wlq, 0)
3221 if rbody == (0 - 1) { return 0 - 1 }
3222 sir_set(m2, fn2, SIR_B, rbody)
3223 return fn2
3224}
3225
3226func main(argc: i64, argv: *i64) -> i64 {
3227 // GE43 PATH: `nx_wgsl compute` -- the compute kernel through both backends (see wg_compute_demo).
3228 if argc > 1 { if wg_streq(argv[1] as *u8, "compute" as *u8) == 1 { return wg_compute_demo() } }
3229 // R-G PATH: `nx_wgsl world` -- the world shader through both backends, see wg_world_demo.
3230 if argc > 1 { if wg_streq(argv[1] as *u8, "world" as *u8) == 1 { return wg_world_demo() } }
3231 // R-F PATH: `nx_wgsl layout` -- the derived uniform layout rows and the stride neg-control, see wg_layout_demo.
3232 if argc > 1 { if wg_streq(argv[1] as *u8, "layout" as *u8) == 1 { return wg_layout_demo() } }
3233 // S12c PATH: `nx_wgsl cast [<glsl-out>]` -- the character cast vertex stage through both backends, see wg_cast_demo.
3234 if argc > 1 { if wg_streq(argv[1] as *u8, "cast" as *u8) == 1 { var co: *u8 = 0 as *u8; var cf: *u8 = 0 as *u8; if argc > 2 { co = argv[2] as *u8 } if argc > 3 { cf = argv[3] as *u8 } return wg_cast_demo(co, cf) } }
3235 // S1..S4 PATH: `nx_wgsl decls` -- the declaration probes (named refusals + positive control), see wg_decls_demo.
3236 if argc > 1 { if wg_streq(argv[1] as *u8, "decls" as *u8) == 1 { return wg_decls_demo() } }
3237 // RUNG 2 PATH: a real .nx source file, through the real front-end, out as both dialects.
3238 if argc > 1 {
3239 let path: *u8 = argv[1] as *u8
3240 let xb: *u8 = sys_mmap(SHL_EXPAND_CAP)
3241 let cx: *ExpandCtx = expand_ctx_new(xb, SHL_EXPAND_CAP)
3242 if expand_imports(cx, path) < 0 { wg_puts("nx_wgsl: expand_imports failed\n" as *u8); return 10 }
3243 let opz: *i64 = cx.out_pos
3244 let endp: i64 = *opz
3245 xb[endp] = 0 as u8
3246 let toks: *Tok = lex_source(xb, SHL_LEX_CAP)
3247 if toks == (0 as *Tok) { wg_puts("nx_wgsl: lex_source failed\n" as *u8); return 2 }
3248 let mm: *Module = parse_module(toks, 0 as *Module)
3249 if mm == (0 as *Module) { wg_puts("nx_wgsl: parse_module failed\n" as *u8); return 3 }
3250 if mm.n_functions <= 0 { wg_puts("nx_wgsl: no functions\n" as *u8); return 4 }
3251 var fi: i64 = 0
3252 while fi < mm.n_functions {
3253 let fb: i64 = mm.functions as i64
3254 let ff: *Function = (fb + fi * NX_MODULE_FN_STRIDE) as *Function
3255 opt_run(ff)
3256 fi = fi + 1
3257 }
3258 let f0: *Function = (mm.functions as i64) as *Function
3259 let m2: *i64 = sir_new()
3260 let fnid: i64 = shl_lower(m2, f0, "shader_main" as *u8)
3261 let nb2: *u8 = sys_mmap(WG_NUMBUF)
3262 var q2: i64 = 0
3263 wg_puts("=== NX-WGSL rung 2: an ORDINARY NishiLang function, through the REAL front-end ===\n" as *u8)
3264 wg_puts("ir_functions=" as *u8)
3265 q2 = eb_num(nb2, 0, WG_NUMBUF, mm.n_functions); nb2[q2] = 0 as u8; wg_puts(nb2)
3266 wg_puts(" ir_blocks=" as *u8)
3267 q2 = eb_num(nb2, 0, WG_NUMBUF, f0.n_blocks); nb2[q2] = 0 as u8; wg_puts(nb2)
3268 wg_puts(" ir_values=" as *u8)
3269 q2 = eb_num(nb2, 0, WG_NUMBUF, f0.n_values); nb2[q2] = 0 as u8; wg_puts(nb2)
3270 wg_puts(" ir_instrs=" as *u8)
3271 q2 = eb_num(nb2, 0, WG_NUMBUF, f0.n_instrs); nb2[q2] = 0 as u8; wg_puts(nb2)
3272 wg_puts("\n" as *u8)
3273 // CFG SHAPE, PRINTED BEFORE ANY LOWERING DECISION. Structured control-flow recovery is a
3274 // CFG-shape problem (rung 2b), and the shape must be MEASURED before an algorithm is
3275 // chosen for it -- picking a reducer for a graph nobody looked at is how a backend ends up
3276 // with a relooper it did not need or a pattern-matcher that cannot see the real cases.
3277 var bi: i64 = 0
3278 while bi < f0.n_blocks {
3279 let bbx: *BasicBlock = block_at(f0, bi)
3280 if (bbx as i64) != 0 {
3281 wg_puts("blk" as *u8)
3282 q2 = eb_num(nb2, 0, WG_NUMBUF, bbx.id); nb2[q2] = 0 as u8; wg_puts(nb2)
3283 wg_puts(" preds=" as *u8)
3284 q2 = eb_num(nb2, 0, WG_NUMBUF, bbx.n_preds); nb2[q2] = 0 as u8; wg_puts(nb2)
3285 wg_puts(" succs=" as *u8)
3286 q2 = eb_num(nb2, 0, WG_NUMBUF, bbx.n_succs); nb2[q2] = 0 as u8; wg_puts(nb2)
3287 if bbx.n_succs > 0 { if (bbx.succ0 as i64) != 0 {
3288 wg_puts(" s0=" as *u8)
3289 q2 = eb_num(nb2, 0, WG_NUMBUF, bbx.succ0.id); nb2[q2] = 0 as u8; wg_puts(nb2)
3290 } }
3291 if bbx.n_succs > 1 { if (bbx.succ1 as i64) != 0 {
3292 wg_puts(" s1=" as *u8)
3293 q2 = eb_num(nb2, 0, WG_NUMBUF, bbx.succ1.id); nb2[q2] = 0 as u8; wg_puts(nb2)
3294 } }
3295 var nin: i64 = 0
3296 var term: i64 = 0
3297 var ix: *Instr = bbx.head
3298 while (ix as i64) != 0 { nin = nin + 1; term = ix.op; ix = ix.next }
3299 wg_puts(" n=" as *u8)
3300 q2 = eb_num(nb2, 0, WG_NUMBUF, nin); nb2[q2] = 0 as u8; wg_puts(nb2)
3301 wg_puts(" term=" as *u8)
3302 q2 = eb_num(nb2, 0, WG_NUMBUF, term); nb2[q2] = 0 as u8; wg_puts(nb2)
3303 wg_puts("\n" as *u8)
3304 }
3305 bi = bi + 1
3306 }
3307 if fnid < 0 {
3308 wg_puts("lower_rc=-1 REFUSED: " as *u8)
3309 wg_puts(sir_cstr(m2, sir_refused(m2)))
3310 wg_puts("\n" as *u8)
3311 return 0
3312 }
3313 let gb2: *u8 = sys_mmap(WG_EMIT_CAP)
3314 let wb2: *u8 = sys_mmap(WG_EMIT_CAP)
3315 let gt2: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
3316 let wt2: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
3317 let gn2: *i64 = sys_mmap(WG_NUMBUF) as *i64
3318 let wn2: *i64 = sys_mmap(WG_NUMBUF) as *i64
3319 gn2[0] = 0
3320 wn2[0] = 0
3321 let gl2: i64 = glsl_emit_module(m2, STAGE_PLAIN, gb2, WG_EMIT_CAP, gt2, WG_TRACE_CAP, gn2)
3322 let wl2: i64 = wgsl_emit_module(m2, STAGE_PLAIN, wb2, WG_EMIT_CAP, wt2, WG_TRACE_CAP, wn2)
3323 wg_puts("\n--- GLSL (from NishiLang) ---\n" as *u8)
3324 if gl2 > 0 { sys_write(1, gb2, gl2) }
3325 wg_puts("\n--- WGSL (from the SAME NishiLang) ---\n" as *u8)
3326 if wl2 > 0 { sys_write(1, wb2, wl2) }
3327 var eq2: i64 = 1
3328 if gn2[0] != wn2[0] { eq2 = 0 }
3329 var i2: i64 = 0
3330 while i2 < gn2[0] {
3331 if i2 < wn2[0] { if gt2[i2] != wt2[i2] { eq2 = 0 } }
3332 i2 = i2 + 1
3333 }
3334 wg_puts("\nlower_rc=0 glsl_nodes=" as *u8)
3335 q2 = eb_num(nb2, 0, WG_NUMBUF, gn2[0]); nb2[q2] = 0 as u8; wg_puts(nb2)
3336 wg_puts(" wgsl_nodes=" as *u8)
3337 q2 = eb_num(nb2, 0, WG_NUMBUF, wn2[0]); nb2[q2] = 0 as u8; wg_puts(nb2)
3338 wg_puts(" trace_equal=" as *u8)
3339 q2 = eb_num(nb2, 0, WG_NUMBUF, eq2); nb2[q2] = 0 as u8; wg_puts(nb2)
3340 wg_puts("\n" as *u8)
3341 return 0
3342 }
3343 let m: *i64 = sir_new()
3344 shsrc_fullscreen_tri(m)
3345 let gb: *u8 = sys_mmap(WG_EMIT_CAP)
3346 let wb: *u8 = sys_mmap(WG_EMIT_CAP)
3347 let gt: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
3348 let wt: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
3349 let gn: *i64 = sys_mmap(WG_NUMBUF) as *i64
3350 let wn: *i64 = sys_mmap(WG_NUMBUF) as *i64
3351 gn[0] = 0
3352 wn[0] = 0
3353 let gl: i64 = glsl_emit_module(m, STAGE_VERTEX, gb, WG_EMIT_CAP, gt, WG_TRACE_CAP, gn)
3354 let wl: i64 = wgsl_emit_module(m, STAGE_VERTEX, wb, WG_EMIT_CAP, wt, WG_TRACE_CAP, wn)
3355 wg_puts("=== NX-WGSL rung 1: ONE NishiLang source, TWO dialects ===\n\n--- GLSL ---\n" as *u8)
3356 if gl > 0 { sys_write(1, gb, gl) }
3357 wg_puts("\n--- WGSL ---\n" as *u8)
3358 if wl > 0 { sys_write(1, wb, wl) }
3359 wg_puts("\nglsl_bytes=" as *u8)
3360 let nb: *u8 = sys_mmap(WG_NUMBUF)
3361 var q: i64 = 0
3362 q = eb_num(nb, 0, WG_NUMBUF, gl); nb[q] = 0 as u8; wg_puts(nb)
3363 wg_puts(" wgsl_bytes=" as *u8)
3364 q = eb_num(nb, 0, WG_NUMBUF, wl); nb[q] = 0 as u8; wg_puts(nb)
3365 wg_puts("\nglsl_nodes=" as *u8)
3366 q = eb_num(nb, 0, WG_NUMBUF, gn[0]); nb[q] = 0 as u8; wg_puts(nb)
3367 wg_puts("\nwgsl_nodes=" as *u8)
3368 q = eb_num(nb, 0, WG_NUMBUF, wn[0]); nb[q] = 0 as u8; wg_puts(nb)
3369 wg_puts("\n" as *u8)
3370 if sir_refused(m) != 0 { wg_puts("REFUSED: " as *u8); wg_puts(sir_cstr(m, sir_refused(m))); wg_puts("\n" as *u8) }
3371 // TRACE IDENTITY, ELEMENT-WISE. Two backends that consumed the SAME source COMPLETELY emit
3372 // the same node ids in the same order. This is the equivalence oracle available on a box with
3373 // no GPU, and it is NOT vacuous: corrupt_nodes below proves a dropped statement changes it.
3374 var eq: i64 = 1
3375 if gn[0] != wn[0] { eq = 0 }
3376 var i9: i64 = 0
3377 while i9 < gn[0] {
3378 if i9 < wn[0] { if gt[i9] != wt[i9] { eq = 0 } }
3379 i9 = i9 + 1
3380 }
3381 wg_puts("trace_equal=" as *u8)
3382 q = eb_num(nb, 0, WG_NUMBUF, eq); nb[q] = 0 as u8; wg_puts(nb)
3383 // NEG-CONTROL 1 -- A CONSTRUCT OUTSIDE THE COVERED SUBSET MUST REFUSE BY NAME. A backend that
3384 // guesses here compiles, links, runs, and draws the wrong picture forever.
3385 let m2: *i64 = sir_new()
3386 let f2: i64 = sir_func(m2, "main" as *u8, T_VOID)
3387 let bad: i64 = sir_ctor(m2, T_MAX + 89)
3388 sir_arg(m2, bad, sir_lit(m2, "0.0" as *u8, T_F32))
3389 sir_stmt(m2, f2, sir_var(m2, "x" as *u8, T_V2F, bad))
3390 let g2: *u8 = sys_mmap(WG_EMIT_CAP)
3391 let t2: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
3392 let n2: *i64 = sys_mmap(WG_NUMBUF) as *i64
3393 n2[0] = 0
3394 let r2: i64 = glsl_emit_module(m2, STAGE_VERTEX, g2, WG_EMIT_CAP, t2, WG_TRACE_CAP, n2)
3395 wg_puts("\nuncovered_rc=" as *u8)
3396 q = eb_num(nb, 0, WG_NUMBUF, r2); nb[q] = 0 as u8; wg_puts(nb)
3397 wg_puts(" uncovered_named=" as *u8)
3398 if sir_refused(m2) != 0 { wg_puts(sir_cstr(m2, sir_refused(m2))) } else { wg_puts("NONE" as *u8) }
3399 // NEG-CONTROL 2 -- A MODULE MISSING ONE STATEMENT MUST NOT TRACE THE SAME. This is what makes
3400 // trace_equal load-bearing rather than decorative.
3401 let m3: *i64 = sir_new()
3402 shsrc_fullscreen_tri(m3)
3403 let f3: i64 = m3[M_FUNCH]
3404 sir_set(m3, sir_get(m3, f3, SIR_B), SIR_NEXT, 0)
3405 let g3: *u8 = sys_mmap(WG_EMIT_CAP)
3406 let t3: *i64 = sys_mmap(WG_TRACE_CAP*8) as *i64
3407 let n3: *i64 = sys_mmap(WG_NUMBUF) as *i64
3408 n3[0] = 0
3409 glsl_emit_module(m3, STAGE_VERTEX, g3, WG_EMIT_CAP, t3, WG_TRACE_CAP, n3)
3410 wg_puts("\ncorrupt_nodes=" as *u8)
3411 q = eb_num(nb, 0, WG_NUMBUF, n3[0]); nb[q] = 0 as u8; wg_puts(nb)
3412 wg_puts("\n" as *u8)
3413 return 0
3414}