gecko-dev/xpcom/glue/SSE.cpp

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/* vim: set shiftwidth=4 tabstop=8 autoindent cindent expandtab: */
2012-05-21 15:12:37 +04:00
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* compile-time and runtime tests for whether to use SSE instructions */
#include "SSE.h"
namespace {
// SSE.h has parallel #ifs which declare MOZILLA_SSE_HAVE_CPUID_DETECTION.
// We can't declare these functions in the header file, however, because
// <intrin.h> conflicts with <windows.h> on MSVC 2005, and some files want to
// include both SSE.h and <windows.h>.
#ifdef HAVE_CPUID_H
// cpuid.h is available on gcc 4.3 and higher on i386 and x86_64
#include <cpuid.h>
enum CPUIDRegister { eax = 0, ebx = 1, ecx = 2, edx = 3 };
static bool
has_cpuid_bit(unsigned int level, CPUIDRegister reg, unsigned int bit)
{
unsigned int regs[4];
return __get_cpuid(level, &regs[0], &regs[1], &regs[2], &regs[3]) &&
(regs[reg] & bit);
}
#elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_AMD64))
// MSVC 2005 or newer on x86-32 or x86-64
#include <intrin.h>
enum CPUIDRegister { eax = 0, ebx = 1, ecx = 2, edx = 3 };
static bool
has_cpuid_bit(unsigned int level, CPUIDRegister reg, unsigned int bit)
{
// Check that the level in question is supported.
int regs[4];
__cpuid(regs, level & 0x80000000u);
if (unsigned(regs[0]) < level)
return false;
__cpuid(regs, level);
return !!(unsigned(regs[reg]) & bit);
}
#elif defined(__SUNPRO_CC) && (defined(__i386) || defined(__x86_64__))
enum CPUIDRegister { eax = 0, ebx = 1, ecx = 2, edx = 3 };
#ifdef __i386
static void
moz_cpuid(int CPUInfo[4], int InfoType)
{
asm (
"xchg %esi, %ebx\n"
"cpuid\n"
"movl %eax, (%edi)\n"
"movl %ebx, 4(%edi)\n"
"movl %ecx, 8(%edi)\n"
"movl %edx, 12(%edi)\n"
"xchg %esi, %ebx\n"
:
: "a"(InfoType), // %eax
"D"(CPUInfo) // %edi
: "%ecx", "%edx", "%esi"
);
}
#else
static void
moz_cpuid(int CPUInfo[4], int InfoType)
{
asm (
"xchg %rsi, %rbx\n"
"cpuid\n"
"movl %eax, (%rdi)\n"
"movl %ebx, 4(%rdi)\n"
"movl %ecx, 8(%rdi)\n"
"movl %edx, 12(%rdi)\n"
"xchg %rsi, %rbx\n"
:
: "a"(InfoType), // %eax
"D"(CPUInfo) // %rdi
: "%ecx", "%edx", "%rsi"
);
}
#endif
static bool
has_cpuid_bit(unsigned int level, CPUIDRegister reg, unsigned int bit)
{
// Check that the level in question is supported.
volatile int regs[4];
moz_cpuid((int *)regs, level & 0x80000000u);
if (unsigned(regs[0]) < level)
return false;
moz_cpuid((int *)regs, level);
return !!(unsigned(regs[reg]) & bit);
}
#endif // end CPUID declarations
}
namespace mozilla {
namespace sse_private {
#if defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
#if !defined(MOZILLA_PRESUME_MMX)
bool mmx_enabled = has_cpuid_bit(1u, edx, (1u<<23));
#endif
#if !defined(MOZILLA_PRESUME_SSE)
bool sse_enabled = has_cpuid_bit(1u, edx, (1u<<25));
#endif
#if !defined(MOZILLA_PRESUME_SSE2)
bool sse2_enabled = has_cpuid_bit(1u, edx, (1u<<26));
#endif
#if !defined(MOZILLA_PRESUME_SSE3)
bool sse3_enabled = has_cpuid_bit(1u, ecx, (1u<<0));
#endif
#if !defined(MOZILLA_PRESUME_SSSE3)
bool ssse3_enabled = has_cpuid_bit(1u, ecx, (1u<<9));
#endif
#if !defined(MOZILLA_PRESUME_SSE4A)
bool sse4a_enabled = has_cpuid_bit(0x80000001u, ecx, (1u<<6));
#endif
#if !defined(MOZILLA_PRESUME_SSE4_1)
bool sse4_1_enabled = has_cpuid_bit(1u, ecx, (1u<<19));
#endif
#if !defined(MOZILLA_PRESUME_SSE4_2)
bool sse4_2_enabled = has_cpuid_bit(1u, ecx, (1u<<20));
#endif
#endif
} // namespace sse_private
} // namespace mozilla