1 // Copyright 2018 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
4
5 //go:build (386 || amd64 || amd64p32) && gccgo
6
7 #include <cpuid.h>
8 #include <stdint.h>
9 #include <x86intrin.h>
10
11 // Need to wrap __get_cpuid_count because it's declared as static.
12 int
gccgoGetCpuidCount(uint32_t leaf,uint32_t subleaf,uint32_t * eax,uint32_t * ebx,uint32_t * ecx,uint32_t * edx)13 gccgoGetCpuidCount(uint32_t leaf, uint32_t subleaf,
14 uint32_t *eax, uint32_t *ebx,
15 uint32_t *ecx, uint32_t *edx)
16 {
17 return __get_cpuid_count(leaf, subleaf, eax, ebx, ecx, edx);
18 }
19
20 #pragma GCC diagnostic ignored "-Wunknown-pragmas"
21 #pragma GCC push_options
22 #pragma GCC target("xsave")
23 #pragma clang attribute push (__attribute__((target("xsave"))), apply_to=function)
24
25 // xgetbv reads the contents of an XCR (Extended Control Register)
26 // specified in the ECX register into registers EDX:EAX.
27 // Currently, the only supported value for XCR is 0.
28 void
gccgoXgetbv(uint32_t * eax,uint32_t * edx)29 gccgoXgetbv(uint32_t *eax, uint32_t *edx)
30 {
31 uint64_t v = _xgetbv(0);
32 *eax = v & 0xffffffff;
33 *edx = v >> 32;
34 }
35
36 #pragma clang attribute pop
37 #pragma GCC pop_options
38