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[RTL}
Replace RtlMoveMemory x86 asm code with the code from CRT's memmove, which is better. Now we can close bug #1941 svn path=/trunk/; revision=50116
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1 changed files with 102 additions and 48 deletions
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@ -210,70 +210,124 @@ ByteZero:
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_RtlMoveMemory@12:
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push ebp
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mov ebp, esp
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/* Save volatiles */
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/* Save non-volatiles */
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push esi
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push edi
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/* Get pointers and size */
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mov esi, [esp+16]
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mov edi, [esp+12]
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mov ecx, [esp+20]
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cld
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mov edi, [ebp + 8]
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mov esi, [ebp + 12]
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mov ecx, [ebp + 16]
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/* Check if the destination is higher (or equal) */
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cmp esi, edi
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jbe Overlap
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/* Use downward copy if source < dest and overlapping */
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cmp edi, esi
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jbe .CopyUp
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mov eax, ecx
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add eax, esi
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cmp edi, eax
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jb .CopyDown
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/* Set ULONG size and UCHAR remainder */
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DoMove:
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mov edx, ecx
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and edx, 3
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shr ecx, 2
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.CopyUp:
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cld
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/* Do the move */
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rep movsd
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or ecx, edx
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jnz ByteMove
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/* Check for small moves */
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cmp ecx, 16
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jb .CopyUpBytes
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/* Return */
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pop edi
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pop esi
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ret 12
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/* Check if its already aligned */
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mov edx, ecx
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test edi, 3
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je .CopyUpDwords
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ByteMove:
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/* Move what's left */
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rep movsb
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/* Make the destination dword aligned */
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mov ecx, edi
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and ecx, 3
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sub ecx, 5
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not ecx
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sub edx, ecx
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rep movsb
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mov ecx, edx
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DoneMove:
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/* Restore volatiles */
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pop edi
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pop esi
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ret 12
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.CopyUpDwords:
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shr ecx, 2
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rep movsd
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mov ecx, edx
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and ecx, 3
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Overlap:
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/* Don't copy if they're equal */
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jz DoneMove
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.CopyUpBytes:
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test ecx, ecx
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je .CopyUpEnd
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rep movsb
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/* Compare pointer distance with given length and check for overlap */
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mov eax, edi
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sub eax, esi
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cmp ecx, eax
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jbe DoMove
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.CopyUpEnd:
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mov eax, [ebp + 8]
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pop edi
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pop esi
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pop ebp
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ret 12
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/* Set direction flag for backward move */
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std
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.CopyDown:
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std
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/* Copy byte-by-byte the non-overlapping distance */
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add esi, ecx
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add edi, ecx
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dec esi
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dec edi
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/* Go to the end of the region */
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add edi, ecx
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add esi, ecx
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/* Check for small moves */
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cmp ecx, 16
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jb .CopyDownSmall
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/* Check if its already aligned */
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mov edx, ecx
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test edi, 3
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je .CopyDownAligned
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/* Make the destination dword aligned */
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mov ecx, edi
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and ecx, 3
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sub edx, ecx
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dec esi
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dec edi
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rep movsb
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mov ecx, edx
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sub esi, 3
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sub edi, 3
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.CopyDownDwords:
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shr ecx, 2
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rep movsd
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mov ecx, edx
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and ecx, 3
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je .CopyDownEnd
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add esi, 3
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add edi, 3
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.CopyDownBytes:
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rep movsb
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.CopyDownEnd:
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cld
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mov eax, [ebp + 8]
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pop edi
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pop esi
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pop ebp
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ret 12
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.CopyDownAligned:
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sub edi, 4
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sub esi, 4
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jmp .CopyDownDwords
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.CopyDownSmall:
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test ecx, ecx
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je .CopyDownEnd
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dec esi
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dec edi
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jmp .CopyDownBytes
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/* Do the move, reset flag and return */
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rep movsb
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cld
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jmp DoneMove
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@RtlPrefetchMemoryNonTemporal@8:
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