Home

nevrax.com

Nevrax.org News Mailing-list Documentation CVS Bugs License

Documentation                       Search   fast_mem.cpp Go to the documentation of this file. /* Copyright, 2000-2002 Nevrax Ltd. * * This file is part of NEVRAX NEL. * NEVRAX NEL is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * NEVRAX NEL 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 NEVRAX NEL; see the file COPYING. If not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, * MA 02111-1307, USA. */ #include "stdmisc.h" #include "nel/misc/fast_mem.h" #include "nel/misc/system_info.h" namespace NLMISC { #ifdef NL_OS_WINDOWS // *************************************************************************** void *CFastMem::memcpySSE(void *dest, const void *src, size_t nbytes) { _asm { mov esi, src mov edi, dest mov ebx, nbytes // edx takes number of bytes%64 mov edx, ebx and edx, 63 // ebx takes number of bytes/64 shr ebx, 6 jz byteCopy loop4k: // flush 4k into temporary buffer push esi mov ecx, ebx // copy per block of 64 bytes. Must not override 64*64= 4096 bytes. cmp ecx, 64 jle skipMiniMize mov ecx, 64 skipMiniMize: // eax takes the number of 64bytes packet for this block. mov eax, ecx loopMemToL1: prefetchnta 64[ESI] // Prefetch next loop, non-temporal prefetchnta 96[ESI] movq mm1, 0[ESI] // Read in source data movq mm2, 8[ESI] movq mm3, 16[ESI] movq mm4, 24[ESI] movq mm5, 32[ESI] movq mm6, 40[ESI] movq mm7, 48[ESI] movq mm0, 56[ESI] add esi, 64 dec ecx jnz loopMemToL1 pop esi // Now copy from L1 to system memory mov ecx, eax loopL1ToMem: movq mm1, 0[ESI] // Read in source data from L1 movq mm2, 8[ESI] movq mm3, 16[ESI] movq mm4, 24[ESI] movq mm5, 32[ESI] movq mm6, 40[ESI] movq mm7, 48[ESI] movq mm0, 56[ESI] movntq 0[EDI], mm1 // Non-temporal stores movntq 8[EDI], mm2 movntq 16[EDI], mm3 movntq 24[EDI], mm4 movntq 32[EDI], mm5 movntq 40[EDI], mm6 movntq 48[EDI], mm7 movntq 56[EDI], mm0 add esi, 64 add edi, 64 dec ecx jnz loopL1ToMem // Do next 4k block sub ebx, eax jnz loop4k emms byteCopy: // Do last bytes with std cpy mov ecx, edx rep movsb } return dest; } // *************************************************************************** void CFastMem::precacheSSE(const void *src, uint nbytes) { _asm { mov esi, src mov ecx, nbytes // 64 bytes per pass shr ecx, 6 jz endLabel loopMemToL1: prefetchnta 64[ESI] // Prefetch next loop, non-temporal prefetchnta 96[ESI] movq mm1, 0[ESI] // Read in source data movq mm2, 8[ESI] movq mm3, 16[ESI] movq mm4, 24[ESI] movq mm5, 32[ESI] movq mm6, 40[ESI] movq mm7, 48[ESI] movq mm0, 56[ESI] add esi, 64 dec ecx jnz loopMemToL1 emms endLabel: } } // *************************************************************************** void CFastMem::precacheMMX(const void *src, uint nbytes) { _asm { mov esi, src mov ecx, nbytes // 64 bytes per pass shr ecx, 6 jz endLabel loopMemToL1: movq mm1, 0[ESI] // Read in source data movq mm2, 8[ESI] movq mm3, 16[ESI] movq mm4, 24[ESI] movq mm5, 32[ESI] movq mm6, 40[ESI] movq mm7, 48[ESI] movq mm0, 56[ESI] add esi, 64 dec ecx jnz loopMemToL1 emms endLabel: } } // *************************************************************************** void CFastMem::precache(const void *src, uint nbytes) { if(NLMISC::CSystemInfo::hasSSE()) precacheSSE(src, nbytes); else if(NLMISC::CSystemInfo::hasMMX()) precacheMMX(src, nbytes); } #else // *************************************************************************** void *CFastMem::memcpySSE(void *dst, const void *src, size_t nbytes) { // Use std memcpy. return memcpy(dst, src, nbytes); } void CFastMem::precacheSSE(const void *src, uint nbytes) { // no-op. } void CFastMem::precacheMMX(const void *src, uint nbytes) { // no-op. } void CFastMem::precache(const void *src, uint nbytes) { // no-op. } #endif typedef void *(*memcpyPtr)(void *dts, const void *src, size_t nbytes); static memcpyPtr findBestmemcpy () { #ifdef NL_OS_WINDOWS if (CSystemInfo::hasSSE ()) return CFastMem::memcpySSE; else return ::memcpy; #else // NL_OS_WINDOWS return ::memcpy; #endif // NL_OS_WINDOWS } void *(*CFastMem::memcpy)(void *dts, const void *src, size_t nbytes) = findBestmemcpy (); } // NLMISC