code wiki / _hdl_build / _clk_probe.nx
_clk_probe.nx source
↩ module page · 24 lines · 1102 B
1// _clk_probe.nx -- empirical check that nx_clock_monotonic_ns() works on the
2// sovereign x86_64 target (rv64 syscall number 113 -> x86 228 via the compiler's
3// translation table). Prints two monotonic reads + their delta in ns/us.
4import "nx_clock.nx"
5
6func cp_p(s: *u8) -> i64 { var n: i64=0; while s[n]!=(0 as u8){n=n+1} sys_write(1,s,n); return 0 }
7func cp_n(v: i64) -> i64 { let bb: *u8=sys_mmap(28); var m: i64=v; if m<0{m=0-m;sys_write(1,"-" as *u8,1)}; let t: *u8=sys_mmap(28); var k: i64=0; if m==0{t[0]=48;k=1}; while m>0{t[k]=(48+(m%10)) as u8;m=m/10;k=k+1}; var i: i64=0; while i<k{bb[i]=t[k-1-i];i=i+1}; sys_write(1,bb,k); return 0 }
8
9func main() -> i64 {
10 let t0: i64 = nx_clock_monotonic_ns()
11 var acc: i64 = 0
12 var i: i64 = 0
13 while i < 5000000 {
14 acc = acc + i
15 i = i + 1
16 }
17 let t1: i64 = nx_clock_monotonic_ns()
18 cp_p("t0=" as *u8); cp_n(t0); cp_p(" t1=" as *u8); cp_n(t1)
19 cp_p(" delta_ns=" as *u8); cp_n(t1 - t0)
20 cp_p(" delta_us=" as *u8); cp_n((t1 - t0) / 1000)
21 cp_p(" acc=" as *u8); cp_n(acc)
22 cp_p("\n" as *u8)
23 return 0
24}