ARMeilleure: Check for XSAVE cpuid flag for AVX{2,512} (#4584)

Protection for the `xgetbv` instruction for systems that do not support
`xcr0` such as nehalem processors.

The `XSAVE` cpuid indicates support for `XSAVE`, `XRESTOR`, `XSETBV`,
`XGETBV` while `OSXSAVE` indicates if the operating system itself has
`XSAVE` turned on. Both must be checked at the same time.
This commit is contained in:
Wunk 2023-03-22 10:51:21 -07:00 committed by GitHub
parent 009c1101d2
commit 0992310b76
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@ -34,6 +34,12 @@ namespace ARMeilleure.CodeGen.X86
private static uint GetXcr0Eax()
{
if (!FeatureInfo1Ecx.HasFlag(FeatureFlags1Ecx.Xsave))
{
// XSAVE feature required for xgetbv
return 0;
}
ReadOnlySpan<byte> asmGetXcr0 = new byte[]
{
0x31, 0xc9, // xor ecx, ecx
@ -70,6 +76,7 @@ namespace ARMeilleure.CodeGen.X86
Sse42 = 1 << 20,
Popcnt = 1 << 23,
Aes = 1 << 25,
Xsave = 1 << 26,
Osxsave = 1 << 27,
Avx = 1 << 28,
F16c = 1 << 29
@ -118,9 +125,9 @@ namespace ARMeilleure.CodeGen.X86
public static bool SupportsSse42 => FeatureInfo1Ecx.HasFlag(FeatureFlags1Ecx.Sse42);
public static bool SupportsPopcnt => FeatureInfo1Ecx.HasFlag(FeatureFlags1Ecx.Popcnt);
public static bool SupportsAesni => FeatureInfo1Ecx.HasFlag(FeatureFlags1Ecx.Aes);
public static bool SupportsAvx => FeatureInfo1Ecx.HasFlag(FeatureFlags1Ecx.Avx | FeatureFlags1Ecx.Osxsave) && Xcr0InfoEax.HasFlag(Xcr0FlagsEax.Sse | Xcr0FlagsEax.YmmHi128);
public static bool SupportsAvx => FeatureInfo1Ecx.HasFlag(FeatureFlags1Ecx.Avx | FeatureFlags1Ecx.Xsave | FeatureFlags1Ecx.Osxsave) && Xcr0InfoEax.HasFlag(Xcr0FlagsEax.Sse | Xcr0FlagsEax.YmmHi128);
public static bool SupportsAvx2 => FeatureInfo7Ebx.HasFlag(FeatureFlags7Ebx.Avx2) && SupportsAvx;
public static bool SupportsAvx512F => FeatureInfo7Ebx.HasFlag(FeatureFlags7Ebx.Avx512f) && FeatureInfo1Ecx.HasFlag(FeatureFlags1Ecx.Osxsave)
public static bool SupportsAvx512F => FeatureInfo7Ebx.HasFlag(FeatureFlags7Ebx.Avx512f) && FeatureInfo1Ecx.HasFlag(FeatureFlags1Ecx.Xsave | FeatureFlags1Ecx.Osxsave)
&& Xcr0InfoEax.HasFlag(Xcr0FlagsEax.Sse | Xcr0FlagsEax.YmmHi128 | Xcr0FlagsEax.Opmask | Xcr0FlagsEax.ZmmHi256 | Xcr0FlagsEax.Hi16Zmm);
public static bool SupportsAvx512Vl => FeatureInfo7Ebx.HasFlag(FeatureFlags7Ebx.Avx512vl) && SupportsAvx512F;
public static bool SupportsAvx512Bw => FeatureInfo7Ebx.HasFlag(FeatureFlags7Ebx.Avx512bw) && SupportsAvx512F;