implement assert_true on x86
The logic implemented here is roughly
assert_true(v):
if any ~v {
int3()
}
in assembly as
```
vptest v, constant 0xffffffff mask
jc ok
int3
ok:
```
jc branches if (~v & mask) are all zero, with mask set fully, that's
branch if ~v are all zero, which is to say, v are all ~0, true. So we
jump over the int3 breakpoint if v are all true.
Cq-Include-Trybots: skia.primary:Test-Debian9-Clang-GCE-CPU-AVX2-x86_64-Debug-All-SK_USE_SKVM_BLITTER
Change-Id: Ie0fc1da15b1a0dba00c66af610ccde18f5985f8a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/253897
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
Auto-Submit: Mike Klein <mtklein@google.com>
2 files changed