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// Copyright (c) 2015 Klaus Post, released under MIT License. See LICENSE file.
//+build amd64,!gccgo,!noasm,!appengine
// func asmCpuid(op uint32) (eax, ebx, ecx, edx uint32)
TEXT ·asmCpuid(SB), 7, $0
XORQ CX, CX
MOVL op+0(FP), AX
CPUID
MOVL AX, eax+8(FP)
MOVL BX, ebx+12(FP)
MOVL CX, ecx+16(FP)
MOVL DX, edx+20(FP)
RET
// func asmCpuidex(op, op2 uint32) (eax, ebx, ecx, edx uint32)
TEXT ·asmCpuidex(SB), 7, $0
MOVL op+0(FP), AX
MOVL op2+4(FP), CX
CPUID
MOVL AX, eax+8(FP)
MOVL BX, ebx+12(FP)
MOVL CX, ecx+16(FP)
MOVL DX, edx+20(FP)
RET
// func asmXgetbv(index uint32) (eax, edx uint32)
TEXT ·asmXgetbv(SB), 7, $0
MOVL index+0(FP), CX
BYTE $0x0f; BYTE $0x01; BYTE $0xd0 // XGETBV
MOVL AX, eax+8(FP)
MOVL DX, edx+12(FP)
RET
// func asmRdtscpAsm() (eax, ebx, ecx, edx uint32)
TEXT ·asmRdtscpAsm(SB), 7, $0
BYTE $0x0F; BYTE $0x01; BYTE $0xF9 // RDTSCP
MOVL AX, eax+0(FP)
MOVL BX, ebx+4(FP)
MOVL CX, ecx+8(FP)
MOVL DX, edx+12(FP)
RET
// From https://go-review.googlesource.com/c/sys/+/285572/
// func asmDarwinHasAVX512() bool
TEXT ·asmDarwinHasAVX512(SB), 7, $0-1
MOVB $0, ret+0(FP) // default to false
#ifdef GOOS_darwin // return if not darwin
#ifdef GOARCH_amd64 // return if not amd64
// These values from:
// https://github.com/apple/darwin-xnu/blob/xnu-4570.1.46/osfmk/i386/cpu_capabilities.h
#define commpage64_base_address 0x00007fffffe00000
#define commpage64_cpu_capabilities64 (commpage64_base_address+0x010)
#define commpage64_version (commpage64_base_address+0x01E)
#define hasAVX512F 0x0000004000000000
MOVQ $commpage64_version, BX
MOVW (BX), AX
CMPW AX, $13 // versions < 13 do not support AVX512
JL no_avx512
MOVQ $commpage64_cpu_capabilities64, BX
MOVQ (BX), AX
MOVQ $hasAVX512F, CX
ANDQ CX, AX
JZ no_avx512
MOVB $1, ret+0(FP)
no_avx512:
#endif
#endif
RET
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