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2d2493a644
Changes to generated code are:
1. In a few places use `vpcmpeqb` instead of `vpcmpneq` to save a
byte of code size.
2. Add a branch for length <= (VEC_SIZE * 6) as opposed to doing
the entire block of [VEC_SIZE * 4 + 1, VEC_SIZE * 8] in a
single basic-block (the space to add the extra branch without
changing code size is bought with the above change).
Change (2) has roughly a 20-25% speedup for sizes in [VEC_SIZE * 4 +
1, VEC_SIZE * 6] and negligible to no-cost for [VEC_SIZE * 6 + 1,
VEC_SIZE * 8]
From N=10 runs on Tigerlake:
align1,align2 ,length ,result ,New Time ,Cur Time ,New Time / Old Time
0 ,0 ,129 ,0 ,5.404 ,6.887 ,0.785
0 ,0 ,129 ,1 ,5.308 ,6.826 ,0.778
0 ,0 ,129 ,18446744073709551615 ,5.359 ,6.823 ,0.785
0 ,0 ,161 ,0 ,5.284 ,6.827 ,0.774
0 ,0 ,161 ,1 ,5.317 ,6.745 ,0.788
0 ,0 ,161 ,18446744073709551615 ,5.406 ,6.778 ,0.798
0 ,0 ,193 ,0 ,6.804 ,6.802 ,1.000
0 ,0 ,193 ,1 ,6.950 ,6.754 ,1.029
0 ,0 ,193 ,18446744073709551615 ,6.792 ,6.719 ,1.011
0 ,0 ,225 ,0 ,6.625 ,6.699 ,0.989
0 ,0 ,225 ,1 ,6.776 ,6.735 ,1.003
0 ,0 ,225 ,18446744073709551615 ,6.758 ,6.738 ,0.992
0 ,0 ,256 ,0 ,5.402 ,5.462 ,0.989
0 ,0 ,256 ,1 ,5.364 ,5.483 ,0.978
0 ,0 ,256 ,18446744073709551615 ,5.341 ,5.539 ,0.964
Rewriting with VMM API allows for memcmpeq-evex to be used with
evex512 by including "x86-evex512-vecs.h" at the top.
Complete check passes on x86-64.
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|---|---|---|
| .. | ||
| aarch64 | ||
| alpha | ||
| arc | ||
| arm | ||
| csky | ||
| generic | ||
| gnu | ||
| hppa | ||
| htl | ||
| hurd | ||
| i386 | ||
| ia64 | ||
| ieee754 | ||
| loongarch | ||
| m68k | ||
| mach | ||
| microblaze | ||
| mips | ||
| nios2 | ||
| nptl | ||
| or1k | ||
| posix | ||
| powerpc | ||
| pthread | ||
| riscv | ||
| s390 | ||
| sh | ||
| sparc | ||
| unix | ||
| wordsize-32 | ||
| wordsize-64 | ||
| x86 | ||
| x86_64 | ||