cmd/compile, simd: capture VAES instructions and fix AVX512VAES feature

The code previously filters out VAES-only instructions, this CL added
them back.

This CL added the VAES feature check following the Intel xed data:

  XED_ISA_SET_VAES:              vaes.7.0.ecx.9 # avx.1.0.ecx.28

This CL also found out that the old AVX512VAES feature check is not
checking the correct bits, it also fixes it:

  XED_ISA_SET_AVX512_VAES_128:    vaes.7.0.ecx.9  aes.1.0.ecx.25  avx512f.7.0.ebx.16 avx512vl.7.0.ebx.31
  XED_ISA_SET_AVX512_VAES_256:    vaes.7.0.ecx.9  aes.1.0.ecx.25  avx512f.7.0.ebx.16 avx512vl.7.0.ebx.31
  XED_ISA_SET_AVX512_VAES_512:    vaes.7.0.ecx.9  aes.1.0.ecx.25  avx512f.7.0.ebx.16

It restricts to the most strict common set - includes avx512vl for even
512-bits although it doesn't requires it.

Change-Id: I4e2f72b312fd2411589fbc12f9ee5c63c09c2e9a
Reviewed-on: https://go-review.googlesource.com/c/go/+/738500
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/src/simd/archsimd/cpu.go b/src/simd/archsimd/cpu.go
index 8069ee7f26..a25556ae65 100644
--- a/src/simd/archsimd/cpu.go
+++ b/src/simd/archsimd/cpu.go
@@ -158,3 +158,13 @@ func (X86Features) FMA() bool {
 func (X86Features) SHA() bool {
 	return cpu.X86.HasSHA
 }
+
+// VAES returns whether the CPU supports the VAES feature.
+//
+// If it returns true, then the CPU also supports AVX.
+//
+// VAES is defined on all GOARCHes, but will only return true on
+// GOARCH amd64.
+func (X86Features) VAES() bool {
+	return cpu.X86.HasVAES
+}