1// Copyright (c) 2015 Klaus Post, released under MIT License. See LICENSE file.
2
3//+build amd64,!gccgo,!noasm,!appengine
4
5// func asmCpuid(op uint32) (eax, ebx, ecx, edx uint32)
6TEXT ·asmCpuid(SB), 7, $0
7 XORQ CX, CX
8 MOVL op+0(FP), AX
9 CPUID
10 MOVL AX, eax+8(FP)
11 MOVL BX, ebx+12(FP)
12 MOVL CX, ecx+16(FP)
13 MOVL DX, edx+20(FP)
14 RET
15
16// func asmCpuidex(op, op2 uint32) (eax, ebx, ecx, edx uint32)
17TEXT ·asmCpuidex(SB), 7, $0
18 MOVL op+0(FP), AX
19 MOVL op2+4(FP), CX
20 CPUID
21 MOVL AX, eax+8(FP)
22 MOVL BX, ebx+12(FP)
23 MOVL CX, ecx+16(FP)
24 MOVL DX, edx+20(FP)
25 RET
26
27// func asmXgetbv(index uint32) (eax, edx uint32)
28TEXT ·asmXgetbv(SB), 7, $0
29 MOVL index+0(FP), CX
30 BYTE $0x0f; BYTE $0x01; BYTE $0xd0 // XGETBV
31 MOVL AX, eax+8(FP)
32 MOVL DX, edx+12(FP)
33 RET
34
35// func asmRdtscpAsm() (eax, ebx, ecx, edx uint32)
36TEXT ·asmRdtscpAsm(SB), 7, $0
37 BYTE $0x0F; BYTE $0x01; BYTE $0xF9 // RDTSCP
38 MOVL AX, eax+0(FP)
39 MOVL BX, ebx+4(FP)
40 MOVL CX, ecx+8(FP)
41 MOVL DX, edx+12(FP)
42 RET
43
44// From https://go-review.googlesource.com/c/sys/+/285572/
45// func asmDarwinHasAVX512() bool
46TEXT ·asmDarwinHasAVX512(SB), 7, $0-1
47 MOVB $0, ret+0(FP) // default to false
48
49#ifdef GOOS_darwin // return if not darwin
50#ifdef GOARCH_amd64 // return if not amd64
51// These values from:
52// https://github.com/apple/darwin-xnu/blob/xnu-4570.1.46/osfmk/i386/cpu_capabilities.h
53#define commpage64_base_address 0x00007fffffe00000
54#define commpage64_cpu_capabilities64 (commpage64_base_address+0x010)
55#define commpage64_version (commpage64_base_address+0x01E)
56#define hasAVX512F 0x0000004000000000
57 MOVQ $commpage64_version, BX
58 MOVW (BX), AX
59 CMPW AX, $13 // versions < 13 do not support AVX512
60 JL no_avx512
61 MOVQ $commpage64_cpu_capabilities64, BX
62 MOVQ (BX), AX
63 MOVQ $hasAVX512F, CX
64 ANDQ CX, AX
65 JZ no_avx512
66 MOVB $1, ret+0(FP)
67
68no_avx512:
69#endif
70#endif
71 RET
72
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