cpuid.hpp
2.18 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
/*
* Distributed under the Boost Software License, Version 1.0.
* (See accompanying file LICENSE_1_0.txt or copy at
* http://www.boost.org/LICENSE_1_0.txt)
*
* Copyright (c) 2020 Andrey Semashev
*/
/*!
* \file cpuid.hpp
*
* This file contains declaration of \c cpuid function
*/
#ifndef BOOST_ATOMIC_CPUID_HPP_INCLUDED_
#define BOOST_ATOMIC_CPUID_HPP_INCLUDED_
#include <boost/predef/architecture/x86.h>
#if BOOST_ARCH_X86
#if defined(_MSC_VER)
#include <intrin.h> // __cpuid
#endif
#include <boost/cstdint.hpp>
#include <boost/atomic/detail/config.hpp>
#include <boost/atomic/detail/header.hpp>
namespace boost {
namespace atomics {
namespace detail {
//! The function invokes x86 cpuid instruction
inline void cpuid(uint32_t& eax, uint32_t& ebx, uint32_t& ecx, uint32_t& edx)
{
#if defined(__GNUC__)
#if (defined(__i386__) || defined(__VXWORKS__)) && (defined(__PIC__) || defined(__PIE__)) && !(defined(__clang__) || (defined(BOOST_GCC) && BOOST_GCC >= 50100))
// Unless the compiler can do it automatically, we have to backup ebx in 32-bit PIC/PIE code because it is reserved by the ABI.
// For VxWorks ebx is reserved on 64-bit as well.
#if defined(__x86_64__)
uint64_t rbx = ebx;
__asm__ __volatile__
(
"xchgq %%rbx, %0\n\t"
"cpuid\n\t"
"xchgq %%rbx, %0\n\t"
: "+DS" (rbx), "+a" (eax), "+c" (ecx), "+d" (edx)
);
ebx = static_cast< uint32_t >(rbx);
#else // defined(__x86_64__)
__asm__ __volatile__
(
"xchgl %%ebx, %0\n\t"
"cpuid\n\t"
"xchgl %%ebx, %0\n\t"
: "+DS" (ebx), "+a" (eax), "+c" (ecx), "+d" (edx)
);
#endif // defined(__x86_64__)
#else
__asm__ __volatile__
(
"cpuid\n\t"
: "+a" (eax), "+b" (ebx), "+c" (ecx), "+d" (edx)
);
#endif
#elif defined(_MSC_VER)
int regs[4] = {};
__cpuid(regs, eax);
eax = regs[0];
ebx = regs[1];
ecx = regs[2];
edx = regs[3];
#else
#error "Boost.Atomic: Unsupported compiler, cpuid instruction cannot be generated"
#endif
}
} // namespace detail
} // namespace atomics
} // namespace boost
#include <boost/atomic/detail/footer.hpp>
#endif // BOOST_ARCH_X86
#endif // BOOST_ATOMIC_CPUID_HPP_INCLUDED_