Nice. The example output on your github page is still wrong, cycles count is
much too high.
Min cycle count seems to be 4 for most simple procs, but that is no problem. I
have just tested a plain string comparison -- about 100 cycles, as expected
from its C code. So string comparison is not a very cheap operation in Nim --
not too surprising, as special nil case has to be considered.
import criterion
var cfg = newDefaultConfig()
benchmark cfg:
proc t0() {.measure.} =
var a = "Rust"
var b = "Nim"
doAssert a != b
proc t1() {.measure.} =
var a = "Rust"
var b = "Nim"
doAssert a > b
Run
$ ./t
Benchmark: t0()
Collected 277 samples
Warning: Found 4 mild and 8 extreme outliers in the time measurements
Warning: Found 4 mild and 6 extreme outliers in the cycles measurements
Time
Mean: 42.4753ns (41.2772ns .. 43.8444ns)
Std: 11.6368ns (7.6329ns .. 16.4890ns)
Slope: 42.2136ns (41.7204ns .. 42.9674ns)
r^2: 0.9977 (0.9960 .. 0.9988)
Cycles
Mean: 108cycles (105cycles .. 111cycles)
Std: 25cycles (18cycles .. 33cycles)
Slope: 109cycles (108cycles .. 111cycles)
r^2: 0.9977 (0.9958 .. 0.9988)
Benchmark: t1()
Collected 275 samples
Warning: Found 21 mild and 5 extreme outliers in the time measurements
Warning: Found 2 mild and 3 extreme outliers in the cycles measurements
Time
Mean: 42.1040ns (41.2619ns .. 42.9831ns)
Std: 7.4068ns (5.1946ns .. 10.0585ns)
Slope: 48.4274ns (46.7242ns .. 49.9679ns)
r^2: 0.9934 (0.9891 .. 0.9968)
Cycles
Mean: 107cycles (105cycles .. 109cycles)
Std: 15cycles (13cycles .. 17cycles)
Slope: 125cycles (121cycles .. 129cycles)
r^2: 0.9934 (0.9886 .. 0.9966)
Run
C code looks like
static N_INLINE(NIM_BOOL, eqStrings)(NimStringDesc* a, NimStringDesc* b) {
NIM_BOOL result;
NI alen;
NI blen;
{ result = (NIM_BOOL)0;
{
if (!(a == b)) goto LA3_;
result = NIM_TRUE;
goto BeforeRet_;
}
LA3_: ;
{
if (!(a == NIM_NIL)) goto LA7_;
alen = ((NI) 0);
}
goto LA5_;
LA7_: ;
{
alen = (*a).Sup.len;
}
LA5_: ;
{
if (!(b == NIM_NIL)) goto LA12_;
blen = ((NI) 0);
}
goto LA10_;
LA12_: ;
{
blen = (*b).Sup.len;
}
LA10_: ;
{
if (!(alen == blen)) goto LA17_;
{
if (!(alen == ((NI) 0))) goto LA21_;
result = NIM_TRUE;
goto BeforeRet_;
}
LA21_: ;
result = equalMem_fmeFeLBvgmAHG9bC8ETS9bYQt(((void*)
((*a).data)), ((void*) ((*b).data)), ((NI) (alen)));
goto BeforeRet_;
}
LA17_: ;
}BeforeRet_: ;
return result;
}
Run
