2. Split x86LowLevel.c into a bunch of C files to make images linked with BaseLib smaller. 3. Fixed a few minor bugs. git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@1066 6f19259b-4bc3-4df7-8a09-765794883524
		
			
				
	
	
		
			93 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			NASM
		
	
	
	
	
	
			
		
		
	
	
			93 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			NASM
		
	
	
	
	
	
| ;------------------------------------------------------------------------------
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| ;
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| ; Copyright (c) 2006, Intel Corporation
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| ; All rights reserved. This program and the accompanying materials
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| ; are licensed and made available under the terms and conditions of the BSD License
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| ; which accompanies this distribution.  The full text of the license may be found at
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| ; http://opensource.org/licenses/bsd-license.php
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| ;
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| ; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
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| ; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
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| ;
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| ; Module Name:
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| ;
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| ;   DivU64x64Remainder.asm
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| ;
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| ; Abstract:
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| ;
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| ;   Calculate the quotient of a 64-bit integer by a 64-bit integer and returns
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| ;   both the quotient and the remainder
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| ;
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| ;------------------------------------------------------------------------------
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| 
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|     .386
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|     .model  flat,C
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|     .code
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| 
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| EXTERN  InternalMathDivRemU64x32:PROC
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| 
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| ;------------------------------------------------------------------------------
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| ; UINT64
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| ; EFIAPI
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| ; InternalMathDivRemU64x64 (
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| ;   IN      UINT64                    Dividend,
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| ;   IN      UINT64                    Divisor,
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| ;   OUT     UINT64                    *Remainder    OPTIONAL
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| ;   );
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| ;------------------------------------------------------------------------------
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| InternalMathDivRemU64x64    PROC
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|     mov     ecx, [esp + 16]
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|     test    ecx, ecx
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|     jnz     _@DivRemU64x64              ; call _@DivRemU64x64 if Divisor > 2^32
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|     mov     ecx, [esp + 20]
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|     jecxz   @F
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|     and     dword ptr [ecx + 4], 0
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|     mov     [esp + 16], ecx
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| @@:
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|     jmp     InternalMathDivRemU64x32
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| InternalMathDivRemU64x64    ENDP
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| 
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| _@DivRemU64x64  PROC    USES    ebx esi edi
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|     mov     edx, dword ptr [esp + 20]
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|     mov     eax, dword ptr [esp + 16]   ; edx:eax <- dividend
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|     mov     edi, edx
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|     mov     esi, eax                    ; edi:esi <- dividend
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|     mov     ebx, dword ptr [esp + 24]   ; ecx:ebx <- divisor
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| @@:
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|     shr     edx, 1
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|     rcr     eax, 1
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|     shrd    ebx, ecx, 1
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|     shr     ecx, 1
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|     jnz     @B
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|     div     ebx
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|     mov     ebx, eax                    ; ebx <- quotient
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|     mov     ecx, [esp + 28]
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|     mul     dword ptr [esp + 24]
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|     imul    ecx, ebx
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|     add     edx, ecx
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|     mov     ecx, dword ptr [esp + 32]
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|     jc      @TooLarge                   ; product > 2^64
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|     cmp     edi, edx                    ; compare high 32 bits
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|     ja      @Correct
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|     jb      @TooLarge                   ; product > dividend
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|     cmp     esi, eax
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|     jae     @Correct                    ; product <= dividend
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| @TooLarge:
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|     dec     ebx                         ; adjust quotient by -1
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|     jecxz   @Return                     ; return if Remainder == NULL
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|     sub     eax, dword ptr [esp + 24]
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|     sbb     edx, dword ptr [esp + 28]
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| @Correct:
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|     jecxz   @Return
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|     sub     esi, eax
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|     sbb     edi, edx                    ; edi:esi <- remainder
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|     mov     [ecx], esi
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|     mov     [ecx + 4], edi
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| @Return:
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|     mov     eax, ebx                    ; eax <- quotient
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|     xor     edx, edx
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|     ret
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| _@DivRemU64x64  ENDP
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| 
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|     END
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