pcsx2/common/include/Utilities/lnx_memzero.h

180 lines
3.9 KiB
C++

/* PCSX2 - PS2 Emulator for PCs
* Copyright (C) 2002-2009 PCSX2 Dev Team
*
* PCSX2 is free software: you can redistribute it and/or modify it under the terms
* of the GNU Lesser General Public License as published by the Free Software Found-
* ation, either version 3 of the License, or (at your option) any later version.
*
* PCSX2 is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
* without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along with PCSX2.
* If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _LNX_MEMZERO_H_
#define _LNX_MEMZERO_H_
// This header contains non-optimized implementation of memzero_ptr and memset8,
// memset16, etc.
template< u32 data, typename T >
static __forceinline void memset32( T& obj )
{
// this function works on 32-bit aligned lengths of data only.
// If the data length is not a factor of 32 bits, the C++ optimizing compiler will
// probably just generate mysteriously broken code in Release builds. ;)
jASSUME( (sizeof(T) & 0x3) == 0 );
u32* dest = (u32*)&obj;
for( int i=sizeof(T)>>2; i; --i, ++dest )
*dest = data;
}
template< uint size >
static __forceinline void memzero_ptr( void* dest )
{
memset( dest, 0, size );
}
template< typename T >
static __forceinline void memzero( T& obj )
{
memset( &obj, 0, sizeof( T ) );
}
template< u8 data, typename T >
static __forceinline void memset8( T& obj )
{
// Aligned sizes use the optimized 32 bit inline memset. Unaligned sizes use memset.
if( (sizeof(T) & 0x3) != 0 )
memset( &obj, data, sizeof( T ) );
else
memset32<data + (data<<8) + (data<<16) + (data<<24)>( obj );
}
template< u16 data, typename T >
static __forceinline void memset16( T& obj )
{
if( (sizeof(T) & 0x3) != 0 )
_memset16_unaligned( &obj, data, sizeof( T ) );
else
memset32<data + (data<<16)>( obj );
}
// An optimized memset for 8 bit destination data.
template< u8 data, size_t bytes >
static __forceinline void memset_8( void *dest )
{
if( bytes == 0 ) return;
if( (bytes & 0x3) != 0 )
{
// unaligned data length. No point in doing an optimized inline version (too complicated!)
// So fall back on the compiler implementation:
memset( dest, data, bytes );
return;
}
// This function only works on 32-bit alignments of data copied.
jASSUME( (bytes & 0x3) == 0 );
enum
{
remdat = bytes>>2,
data32 = data + (data<<8) + (data<<16) + (data<<24)
};
// macro to execute the x86/32 "stosd" copies.
switch( remdat )
{
case 1:
*(u32*)dest = data32;
return;
case 2:
((u32*)dest)[0] = data32;
((u32*)dest)[1] = data32;
return;
case 3:
__asm__ volatile
(
".intel_syntax noprefix\n"
"cld\n"
// "mov edi, %[dest]\n"
// "mov eax, %[data32]\n"
"stosd\n"
"stosd\n"
"stosd\n"
".att_syntax\n"
:
// Input specifiers: D - edi, a -- eax, c ecx
: [dest]"D"(dest), [data32]"a"(data32)
: "memory"
);
return;
case 4:
__asm__ volatile
(
".intel_syntax noprefix\n"
"cld\n"
// "mov edi, %[dest]\n"
// "mov eax, %[data32]\n"
"stosd\n"
"stosd\n"
"stosd\n"
"stosd\n"
".att_syntax\n"
:
: [dest]"D"(dest), [data32]"a"(data32)
: "memory"
);
return;
case 5:
__asm__ volatile
(
".intel_syntax noprefix\n"
"cld\n"
// "mov edi, %[dest]\n"
// "mov eax, %[data32]\n"
"stosd\n"
"stosd\n"
"stosd\n"
"stosd\n"
"stosd\n"
".att_syntax\n"
:
: [dest]"D"(dest), [data32]"a"(data32)
: "memory"
);
return;
default:
__asm__ volatile
(
".intel_syntax noprefix\n"
"cld\n"
// "mov ecx, %[remdat]\n"
// "mov edi, %[dest]\n"
// "mov eax, %\[data32]n"
"rep stosd\n"
".att_syntax\n"
:
: [remdat]"c"(remdat), [dest]"D"(dest), [data32]"a"(data32)
: "memory"
);
return;
}
}
#endif