libgo/go/internal/cpu/cpu_gccgo.c

   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 #include <stdint.h>
   6
   7 #if defined(__i386__) || defined(__x86_64__)
   8 #include <cpuid.h>
   9 #include <x86intrin.h>
  10 #endif
  11
  12 #include "runtime.h"
  13
  14 #if defined(__i386__) || defined(__x86_64__)
  15
  16 struct cpuid_ret {
  17         uint32_t eax;
  18         uint32_t ebx;
  19         uint32_t ecx;
  20         uint32_t edx;
  21 };
  22
  23 struct cpuid_ret cpuid(uint32_t, uint32_t)
  24   __asm__(GOSYM_PREFIX "internal_cpu.cpuid")
  25   __attribute__((no_split_stack));
  26
  27 struct cpuid_ret cpuid(uint32_t eaxArg, uint32_t ecxArg) {
  28         unsigned int eax = 0;
  29         unsigned int ebx = 0;
  30         unsigned int ecx = 0;
  31         unsigned int edx = 0;
  32         struct cpuid_ret ret;
  33
  34         __get_cpuid_count(eaxArg, ecxArg, &eax, &ebx, &ecx, &edx);
  35         ret.eax = (uint32_t)(eax);
  36         ret.ebx = (uint32_t)(ebx);
  37         ret.ecx = (uint32_t)(ecx);
  38         ret.edx = (uint32_t)(edx);
  39         return ret;
  40 }
  41
  42 struct xgetbv_ret {
  43         uint32_t eax;
  44         uint32_t edx;
  45 };
  46
  47 struct xgetbv_ret xgetbv(void)
  48   __asm__(GOSYM_PREFIX "internal_cpu.xgetbv")
  49   __attribute__((no_split_stack));
  50
  51 #pragma GCC push_options
  52 #pragma GCC target("xsave")
  53
  54 struct xgetbv_ret xgetbv(void) {
  55         struct xgetbv_ret ret;
  56
  57         // At some point, use call to _xgetbv() instead:
  58         //
  59         //       long long r = _xgetbv(0);
  60         //       ret.eax = r & 0xffffffff;
  61         //       ret.edx = r >> 32;
  62         //
  63         unsigned int __eax, __edx, __xcr_no = 0;
  64         __asm__ ("xgetbv" : "=a" (__eax), "=d" (__edx) : "c" (__xcr_no));
  65         ret.eax = __eax;
  66         ret.edx = __edx;
  67         return ret;
  68 }
  69
  70 #pragma GCC pop_options
  71
  72 #endif /* defined(__i386__) || defined(__x86_64__)  */