hl2_src-leak-2017/src/tier1/processor_detect.cpp

275 lines
6.1 KiB
C++

//========= Copyright Valve Corporation, All rights reserved. ============//
//
// Purpose: win32 dependant ASM code for CPU capability detection
//
// $Workfile: $
// $NoKeywords: $
//=============================================================================//
#if defined( _X360 ) || defined( WIN64 )
bool CheckMMXTechnology(void) { return false; }
bool CheckSSETechnology(void) { return false; }
bool CheckSSE2Technology(void) { return false; }
bool Check3DNowTechnology(void) { return false; }
#elif defined( _WIN32 ) && !defined( _X360 )
#pragma optimize( "", off )
#pragma warning( disable: 4800 ) //'int' : forcing value to bool 'true' or 'false' (performance warning)
// stuff from windows.h
#ifndef EXCEPTION_EXECUTE_HANDLER
#define EXCEPTION_EXECUTE_HANDLER 1
#endif
bool CheckMMXTechnology(void)
{
int retval = true;
unsigned int RegEDX = 0;
#ifdef CPUID
_asm pushad;
#endif
__try
{
_asm
{
#ifdef CPUID
xor edx, edx // Clue the compiler that EDX is about to be used.
#endif
mov eax, 1 // set up CPUID to return processor version and features
// 0 = vendor string, 1 = version info, 2 = cache info
CPUID // code bytes = 0fh, 0a2h
mov RegEDX, edx // features returned in edx
}
}
__except(EXCEPTION_EXECUTE_HANDLER)
{
retval = false;
}
// If CPUID not supported, then certainly no MMX extensions.
if (retval)
{
if (RegEDX & 0x800000) // bit 23 is set for MMX technology
{
__try
{
// try executing the MMX instruction "emms"
_asm EMMS
}
__except(EXCEPTION_EXECUTE_HANDLER)
{
retval = false;
}
}
else
retval = false; // processor supports CPUID but does not support MMX technology
// if retval == 0 here, it means the processor has MMX technology but
// floating-point emulation is on; so MMX technology is unavailable
}
#ifdef CPUID
_asm popad;
#endif
return retval;
}
bool CheckSSETechnology(void)
{
int retval = true;
unsigned int RegEDX = 0;
#ifdef CPUID
_asm pushad;
#endif
// Do we have support for the CPUID function?
__try
{
_asm
{
#ifdef CPUID
xor edx, edx // Clue the compiler that EDX is about to be used.
#endif
mov eax, 1 // set up CPUID to return processor version and features
// 0 = vendor string, 1 = version info, 2 = cache info
CPUID // code bytes = 0fh, 0a2h
mov RegEDX, edx // features returned in edx
}
}
__except(EXCEPTION_EXECUTE_HANDLER)
{
retval = false;
}
// If CPUID not supported, then certainly no SSE extensions.
if (retval)
{
// Do we have support for SSE in this processor?
if ( RegEDX & 0x2000000L ) // bit 25 is set for SSE technology
{
// Make sure that SSE is supported by executing an inline SSE instruction
// BUGBUG, FIXME - Visual C Version 6.0 does not support SSE inline code YET (No macros from Intel either)
// Fix this if VC7 supports inline SSE instructinons like "xorps" as shown below.
#if 1
__try
{
_asm
{
// Attempt execution of a SSE instruction to make sure OS supports SSE FPU context switches
xorps xmm0, xmm0
// This will work on Win2k+ (Including masking SSE FPU exception to "normalized" values)
// This will work on Win98+ (But no "masking" of FPU exceptions provided)
}
}
__except(EXCEPTION_EXECUTE_HANDLER)
#endif
{
retval = false;
}
}
else
retval = false;
}
#ifdef CPUID
_asm popad;
#endif
return retval;
}
bool CheckSSE2Technology(void)
{
int retval = true;
unsigned int RegEDX = 0;
#ifdef CPUID
_asm pushad;
#endif
// Do we have support for the CPUID function?
__try
{
_asm
{
#ifdef CPUID
xor edx, edx // Clue the compiler that EDX is about to be used.
#endif
mov eax, 1 // set up CPUID to return processor version and features
// 0 = vendor string, 1 = version info, 2 = cache info
CPUID // code bytes = 0fh, 0a2h
mov RegEDX, edx // features returned in edx
}
}
__except(EXCEPTION_EXECUTE_HANDLER)
{
retval = false;
}
// If CPUID not supported, then certainly no SSE extensions.
if (retval)
{
// Do we have support for SSE in this processor?
if ( RegEDX & 0x04000000 ) // bit 26 is set for SSE2 technology
{
// Make sure that SSE is supported by executing an inline SSE instruction
__try
{
_asm
{
// Attempt execution of a SSE2 instruction to make sure OS supports SSE FPU context switches
xorpd xmm0, xmm0
}
}
__except(EXCEPTION_EXECUTE_HANDLER)
{
retval = false;
}
}
else
retval = false;
}
#ifdef CPUID
_asm popad;
#endif
return retval;
}
bool Check3DNowTechnology(void)
{
int retval = true;
unsigned int RegEAX = 0;
#ifdef CPUID
_asm pushad;
#endif
// First see if we can execute CPUID at all
__try
{
_asm
{
#ifdef CPUID
// xor edx, edx // Clue the compiler that EDX is about to be used.
#endif
mov eax, 0x80000000 // setup CPUID to return whether AMD >0x80000000 function are supported.
// 0x80000000 = Highest 0x80000000+ function, 0x80000001 = 3DNow support
CPUID // code bytes = 0fh, 0a2h
mov RegEAX, eax // result returned in eax
}
}
__except(EXCEPTION_EXECUTE_HANDLER)
{
retval = false;
}
// If CPUID not supported, then there is definitely no 3DNow support
if (retval)
{
// Are there any "higher" AMD CPUID functions?
if (RegEAX > 0x80000000L )
{
__try
{
_asm
{
mov eax, 0x80000001 // setup to test for CPU features
CPUID // code bytes = 0fh, 0a2h
shr edx, 31 // If bit 31 is set, we have 3DNow support!
mov retval, edx // Save the return value for end of function
}
}
__except(EXCEPTION_EXECUTE_HANDLER)
{
retval = false;
}
}
else
{
// processor supports CPUID but does not support AMD CPUID functions
retval = false;
}
}
#ifdef CPUID
_asm popad;
#endif
return retval;
}
#pragma optimize( "", on )
#endif // _WIN32