| // Copyright 2018 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| // +build 386 amd64 amd64p32 |
| // +build gccgo |
| |
| #include <cpuid.h> |
| #include <stdint.h> |
| |
| // Need to wrap __get_cpuid_count because it's declared as static. |
| int |
| gccgoGetCpuidCount(uint32_t leaf, uint32_t subleaf, |
| uint32_t *eax, uint32_t *ebx, |
| uint32_t *ecx, uint32_t *edx) |
| { |
| return __get_cpuid_count(leaf, subleaf, eax, ebx, ecx, edx); |
| } |
| |
| // xgetbv reads the contents of an XCR (Extended Control Register) |
| // specified in the ECX register into registers EDX:EAX. |
| // Currently, the only supported value for XCR is 0. |
| // |
| // TODO: Replace with a better alternative: |
| // |
| // #include <xsaveintrin.h> |
| // |
| // #pragma GCC target("xsave") |
| // |
| // void gccgoXgetbv(uint32_t *eax, uint32_t *edx) { |
| // unsigned long long x = _xgetbv(0); |
| // *eax = x & 0xffffffff; |
| // *edx = (x >> 32) & 0xffffffff; |
| // } |
| // |
| // Note that _xgetbv is defined starting with GCC 8. |
| void |
| gccgoXgetbv(uint32_t *eax, uint32_t *edx) |
| { |
| __asm(" xorl %%ecx, %%ecx\n" |
| " xgetbv" |
| : "=a"(*eax), "=d"(*edx)); |
| } |
