qbit/go
1
0
Fork 0
mirror of https://github.com/golang/go synced 2024-11-19 18:54:41 -07:00
Code Releases Activity

internal/cpu: align capability definitions for x86 with other architectures

Browse Source 
Use constant masks and align the definition of isSet with
arm64 and ppc64x.

Change-Id: I0c6eae30da5e3ce797cde0dab4a39855d4d245d9
Reviewed-on: https://go-review.googlesource.com/94759
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This commit is contained in:
Martin Möhrmann 2018-02-04 20:39:39 +01:00 committed by Brad Fitzpatrick
parent 954f651ccc
commit 7289607b1b
1 changed files with 43 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

62
src/internal/cpu/cpu_x86.go
View File

@ -14,6 +14,30 @@ func cpuid(eaxArg, ecxArg uint32) (eax, ebx, ecx, edx uint32)
// xgetbv with ecx = 0 is implemented in cpu_x86.s.
func xgetbv() (eax, edx uint32)
const (
// edx bits
cpuid_SSE2 = 1 << 26
// ecx bits
cpuid_SSE3 = 1 << 0
cpuid_PCLMULQDQ = 1 << 1
cpuid_SSSE3 = 1 << 9
cpuid_FMA = 1 << 12
cpuid_SSE41 = 1 << 19
cpuid_SSE42 = 1 << 20
cpuid_POPCNT = 1 << 23
cpuid_AES = 1 << 25
cpuid_OSXSAVE = 1 << 27
cpuid_AVX = 1 << 28
// ebx bits
cpuid_BMI1 = 1 << 3
cpuid_AVX2 = 1 << 5
cpuid_BMI2 = 1 << 8
cpuid_ERMS = 1 << 9
cpuid_ADX = 1 << 19
)
func doinit() {
maxID, _, _, _ := cpuid(0, 0)
@ -22,40 +46,40 @@ func doinit() {
}
_, _, ecx1, edx1 := cpuid(1, 0)
X86.HasSSE2 = isSet(26, edx1)
X86.HasSSE2 = isSet(edx1, cpuid_SSE2)
X86.HasSSE3 = isSet(0, ecx1)
X86.HasPCLMULQDQ = isSet(1, ecx1)
X86.HasSSSE3 = isSet(9, ecx1)
X86.HasFMA = isSet(12, ecx1)
X86.HasSSE41 = isSet(19, ecx1)
X86.HasSSE42 = isSet(20, ecx1)
X86.HasPOPCNT = isSet(23, ecx1)
X86.HasAES = isSet(25, ecx1)
X86.HasOSXSAVE = isSet(27, ecx1)
X86.HasSSE3 = isSet(ecx1, cpuid_SSE3)
X86.HasPCLMULQDQ = isSet(ecx1, cpuid_PCLMULQDQ)
X86.HasSSSE3 = isSet(ecx1, cpuid_SSSE3)
X86.HasFMA = isSet(ecx1, cpuid_FMA)
X86.HasSSE41 = isSet(ecx1, cpuid_SSE41)
X86.HasSSE42 = isSet(ecx1, cpuid_SSE42)
X86.HasPOPCNT = isSet(ecx1, cpuid_POPCNT)
X86.HasAES = isSet(ecx1, cpuid_AES)
X86.HasOSXSAVE = isSet(ecx1, cpuid_OSXSAVE)
osSupportsAVX := false
// For XGETBV, OSXSAVE bit is required and sufficient.
if X86.HasOSXSAVE {
eax, _ := xgetbv()
// Check if XMM and YMM registers have OS support.
osSupportsAVX = isSet(1, eax) && isSet(2, eax)
osSupportsAVX = isSet(eax, 1<<1) && isSet(eax, 1<<2)
}
X86.HasAVX = isSet(28, ecx1) && osSupportsAVX
X86.HasAVX = isSet(ecx1, cpuid_AVX) && osSupportsAVX
if maxID < 7 {
return
}
_, ebx7, _, _ := cpuid(7, 0)
X86.HasBMI1 = isSet(3, ebx7)
X86.HasAVX2 = isSet(5, ebx7) && osSupportsAVX
X86.HasBMI2 = isSet(8, ebx7)
X86.HasERMS = isSet(9, ebx7)
X86.HasADX = isSet(19, ebx7)
X86.HasBMI1 = isSet(ebx7, cpuid_BMI1)
X86.HasAVX2 = isSet(ebx7, cpuid_AVX2) && osSupportsAVX
X86.HasBMI2 = isSet(ebx7, cpuid_BMI2)
X86.HasERMS = isSet(ebx7, cpuid_ERMS)
X86.HasADX = isSet(ebx7, cpuid_ADX)
}
func isSet(bitpos uint, value uint32) bool {
return value&(1<<bitpos) != 0
func isSet(hwc uint32, value uint32) bool {
return hwc&value != 0
}