Inline ASM in .c file is specific to MS tool-chain. Other tool-chain (such as Intel compiler) may not support it. Add in .asm files to make these function to be built by Assembler so that they are avaliable too for other tool-chain.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@5529 6f19259b-4bc3-4df7-8a09-765794883524
This commit is contained in:
qwang12
2008-07-21 01:49:04 +00:00
parent 22353b17c0
commit 478db76bbe
10 changed files with 1026 additions and 0 deletions

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;/*++
;
;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:
;
; EfiZeroMem.c
;
;Abstract:
;
; This is the code that supports IA32-optimized ZeroMem service
;
;--*/
;---------------------------------------------------------------------------
.686
.model flat,C
.mmx
.code
;---------------------------------------------------------------------------
;VOID
;EfiCommonLibZeroMem (
; IN VOID *Buffer,
; IN UINTN Count
; )
;/*++
;
;Input: VOID *Buffer - Pointer to buffer to clear
; UINTN Count - Number of bytes to clear
;
;Output: None.
;
;Saves:
;
;Modifies:
;
;Description: This function is an optimized zero-memory function.
;
;Notes: This function tries to zero 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.
;
;--*/
EfiCommonLibZeroMem PROC
; UINT64 MmxSave;
push ebp
mov ebp, esp
push ecx ; Reserve space for local variable MmxSave
push ecx
push edi
mov ecx, [ebp + 0Ch] ; Count
mov edi, [ebp + 8]; Buffer
; Pick up misaligned start bytes (get pointer 4-byte aligned)
_StartByteZero:
mov eax, edi
and al, 3 ; check lower 2 bits of address
test al, al
je _ZeroBlocks ; already aligned?
cmp ecx, 0
je _ZeroMemDone
; Clear the byte memory location
mov BYTE PTR [edi], 0
inc edi
; Decrement our count
dec ecx
jmp _StartByteZero ; back to top of loop
_ZeroBlocks:
; Compute how many 64-byte blocks we can clear
mov edx, ecx
shr ecx, 6 ; convert to 64-byte count
shl ecx, 6 ; convert back to bytes
sub edx, ecx ; subtract from the original count
shr ecx, 6 ; and this is how many 64-byte blocks
; If no 64-byte blocks, then skip
cmp ecx, 0
je _ZeroRemaining
; Save mm0
movq [ebp - 8], mm0 ; Save mm0 to MmxSave
pxor mm0, mm0 ; Clear mm0
_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 ecx
jnz _B
; Restore mm0
movq mm0, [ebp - 8] ; Restore mm0 from MmxSave
emms ; Exit MMX Instruction
_ZeroRemaining:
; Zero out as many DWORDS as possible
mov ecx, edx
shr ecx, 2
xor eax, eax
rep stosd
; Zero out remaining as bytes
mov ecx, edx
and ecx, 03
rep stosb
_ZeroMemDone:
pop edi
leave
ret
EfiCommonLibZeroMem ENDP
END