diff options
Diffstat (limited to 'EdkCompatibilityPkg/Foundation/Library/EfiCommonLib/Ia32/EfiSetMem.c')
-rw-r--r-- | EdkCompatibilityPkg/Foundation/Library/EfiCommonLib/Ia32/EfiSetMem.c | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/EdkCompatibilityPkg/Foundation/Library/EfiCommonLib/Ia32/EfiSetMem.c b/EdkCompatibilityPkg/Foundation/Library/EfiCommonLib/Ia32/EfiSetMem.c new file mode 100644 index 0000000000..2543679c58 --- /dev/null +++ b/EdkCompatibilityPkg/Foundation/Library/EfiCommonLib/Ia32/EfiSetMem.c @@ -0,0 +1,139 @@ +/*++
+
+Copyright (c) 2006, Intel Corporation
+All rights reserved. This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution. The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+Module Name:
+
+ EfiSetMem.c
+
+Abstract:
+
+ This is the code that supports IA32-optimized SetMem service
+
+--*/
+
+#include "Tiano.h"
+
+VOID
+EfiCommonLibSetMem (
+ IN VOID *Buffer,
+ IN UINTN Count,
+ IN UINT8 Value
+ )
+/*++
+
+Input: VOID *Buffer - Pointer to buffer to write
+ UINTN Count - Number of bytes to write
+ UINT8 Value - Value to write
+
+Output: None.
+
+Saves:
+
+Modifies:
+
+Description: This function is an optimized set-memory function.
+
+Notes: This function tries to set memory 8 bytes at a time. As a result,
+ it first picks up any misaligned bytes, then words, before getting
+ in the main loop that does the 8-byte clears.
+
+--*/
+{
+ UINT64 QWordValue;
+ UINT64 MmxSave;
+ __asm {
+ mov edx, Count
+ test edx, edx
+ je _SetMemDone
+
+ push ebx
+
+ mov eax, Buffer
+ mov bl, Value
+ mov edi, eax
+ mov bh, bl
+
+ cmp edx, 256
+ jb _SetRemindingByte
+
+ and al, 07h
+ test al, al
+ je _SetBlock
+
+ mov eax, edi
+ shr eax, 3
+ inc eax
+ shl eax, 3
+ sub eax, edi
+ cmp eax, edx
+ jnb _SetRemindingByte
+
+ sub edx, eax
+ mov ecx, eax
+
+ mov al, bl
+ rep stosb
+
+_SetBlock:
+ mov eax, edx
+ shr eax, 6
+ test eax, eax
+ je _SetRemindingByte
+
+ shl eax, 6
+ sub edx, eax
+ shr eax, 6
+
+ mov WORD PTR QWordValue[0], bx
+ mov WORD PTR QWordValue[2], bx
+ mov WORD PTR QWordValue[4], bx
+ mov WORD PTR QWordValue[6], bx
+
+
+ movq MmxSave, mm0
+ movq mm0, QWordValue
+
+_B:
+ movq QWORD PTR ds:[edi], mm0
+ movq QWORD PTR ds:[edi+8], mm0
+ movq QWORD PTR ds:[edi+16], mm0
+ movq QWORD PTR ds:[edi+24], mm0
+ movq QWORD PTR ds:[edi+32], mm0
+ movq QWORD PTR ds:[edi+40], mm0
+ movq QWORD PTR ds:[edi+48], mm0
+ movq QWORD PTR ds:[edi+56], mm0
+ add edi, 64
+ dec eax
+ jnz _B
+
+; Restore mm0
+ movq mm0, MmxSave
+ emms ; Exit MMX Instruction
+
+_SetRemindingByte:
+ mov ecx, edx
+
+ mov eax, ebx
+ shl eax, 16
+ mov ax, bx
+ shr ecx, 2
+ rep stosd
+
+ mov ecx, edx
+ and ecx, 3
+ rep stosb
+
+ pop ebx
+
+_SetMemDone:
+
+ }
+}
|