diff options
Diffstat (limited to 'EDK/Foundation/Library/EdkIIGlueLib/Library/BaseLib/Ia32/DivU64x64Remainder.asm')
-rw-r--r-- | EDK/Foundation/Library/EdkIIGlueLib/Library/BaseLib/Ia32/DivU64x64Remainder.asm | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/EDK/Foundation/Library/EdkIIGlueLib/Library/BaseLib/Ia32/DivU64x64Remainder.asm b/EDK/Foundation/Library/EdkIIGlueLib/Library/BaseLib/Ia32/DivU64x64Remainder.asm new file mode 100644 index 0000000..eb16032 --- /dev/null +++ b/EDK/Foundation/Library/EdkIIGlueLib/Library/BaseLib/Ia32/DivU64x64Remainder.asm @@ -0,0 +1,90 @@ +; Copyright (c) 2004, 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: +; +; DivU64x64Remainder.asm +; +; Abstract: +; +; Calculate the quotient of a 64-bit integer by a 64-bit integer and returns +; both the quotient and the remainder +; +;------------------------------------------------------------------------------ + + .386 + .model flat,C + .code + +EXTERN InternalMathDivRemU64x32:PROC + +;------------------------------------------------------------------------------ +; UINT64 +; EFIAPI +; InternalMathDivRemU64x64 ( +; IN UINT64 Dividend, +; IN UINT64 Divisor, +; OUT UINT64 *Remainder OPTIONAL +; ); +;------------------------------------------------------------------------------ +InternalMathDivRemU64x64 PROC + mov ecx, [esp + 16] + test ecx, ecx + jnz _@DivRemU64x64 ; call _@DivRemU64x64 if Divisor > 2^32 + mov ecx, [esp + 20] + jecxz @F + and dword ptr [ecx + 4], 0 + mov [esp + 16], ecx +@@: + jmp InternalMathDivRemU64x32 +InternalMathDivRemU64x64 ENDP + +_@DivRemU64x64 PROC USES ebx esi edi + mov edx, dword ptr [esp + 20] + mov eax, dword ptr [esp + 16] ; edx:eax <- dividend + mov edi, edx + mov esi, eax ; edi:esi <- dividend + mov ebx, dword ptr [esp + 24] ; ecx:ebx <- divisor +@@: + shr edx, 1 + rcr eax, 1 + shrd ebx, ecx, 1 + shr ecx, 1 + jnz @B + div ebx + mov ebx, eax ; ebx <- quotient + mov ecx, [esp + 28] + mul dword ptr [esp + 24] + imul ecx, ebx + add edx, ecx + mov ecx, dword ptr [esp + 32] + jc @TooLarge ; product > 2^64 + cmp edi, edx ; compare high 32 bits + ja @Correct + jb @TooLarge ; product > dividend + cmp esi, eax + jae @Correct ; product <= dividend +@TooLarge: + dec ebx ; adjust quotient by -1 + jecxz @Return ; return if Remainder == NULL + sub eax, dword ptr [esp + 24] + sbb edx, dword ptr [esp + 28] +@Correct: + jecxz @Return + sub esi, eax + sbb edi, edx ; edi:esi <- remainder + mov [ecx], esi + mov [ecx + 4], edi +@Return: + mov eax, ebx ; eax <- quotient + xor edx, edx + ret +_@DivRemU64x64 ENDP + + END |