nx_opt_eqsat_wire_gate.nx

nx_opt_eqsat_wire_gate.nx -- GATE for LN8 "equality saturation CONSUMED by the backend" (lang.plan rung LN8, symbol opt_eqsat_pass). nx_opt_eqsat_pass_gate proves the PASS on an in-memory IR fixture; THIS gate proves the SHIPPING PIPELINE runs it: the toolchain compiler (argv[1], default the live builder) is driven over runtime/nx_eqsat_wire_probe.nx with --ir-dump and the post-opt IR is read back. Observables (both measured 2026-08-23 on the first wired build, neither assumed): * ewp_xor_self (x ^ x, x a runtime param): the xor folds to the constant 0 through the e-graph and is then dead-code-eliminated, so the dump carries NO `op=12` line whose operands are the SAME value id; the emitted asm goes from `xorq %rcx, %rax` to `movabsq $0, %rax`. * ewp_xor_pair (x ^ y, distinct params): the xor SURVIVES -- exactly one `op=12` line with o0 != o1. This is the anti-vacuity control: a pipeline that deleted every xor would fail it. * Behaviour is unchanged: the probe exits argc+3 with and without the pass (exit 4 unarg'd). A pre-LN8 compiler (no pass in opt_run) fails the fold tooth and keeps both xors; a pre-LN8 compiler without --ir-dump fails the dump-present tooth too -- both are the bite, attributable. Driver = nx_ccgate_lib. Data captures in /tmp/nxeqw/, RUNNABLES under _build/ (NAS /tmp noexec). Usage: nx_opt_eqsat_wire_gate [compiler_elf] (CWD = the tree root, like nx_cc_equiv_gate) license_tier: ORIGINAL No hw writes (Rule 26).