+++ /dev/null
-/*
- * COPYRIGHT: See COPYING in the top level directory
- * PROJECT: ReactOS kernel
- * PURPOSE: Run-Time Library
- * FILE: lib/sdk/crt/math/i386/allmul_asm.s
- * PROGRAMER: Alex Ionescu (alex@relsoft.net)
- *
- * Copyright (C) 2002 Michael Ringgaard.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the project nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
-
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES// LOSS OF USE, DATA, OR PROFITS// OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#include <asm.inc>
-
-PUBLIC __allmul
-
-/* FUNCTIONS ***************************************************************/
-.code
-
-//
-// llmul - long multiply routine
-//
-// Purpose:
-// Does a long multiply (same for signed/unsigned)
-// Parameters are not changed.
-//
-// Entry:
-// Parameters are passed on the stack:
-// 1st pushed: multiplier (QWORD)
-// 2nd pushed: multiplicand (QWORD)
-//
-// Exit:
-// EDX:EAX - product of multiplier and multiplicand
-// NOTE: parameters are removed from the stack
-//
-// Uses:
-// ECX
-//
-
-__allmul:
-
-#define ALO [esp + 4] // stack address of a
-#define AHI [esp + 8] // stack address of a
-#define BLO [esp + 12] // stack address of b
-#define BHI [esp + 16] // stack address of b
-
-//
-// AHI, BHI : upper 32 bits of A and B
-// ALO, BLO : lower 32 bits of A and B
-//
-// ALO * BLO
-// ALO * BHI
-// + BLO * AHI
-// ---------------------
-//
-
- mov eax,AHI
- mov ecx,BHI
- or ecx,eax //test for both hiwords zero.
- mov ecx,BLO
- jnz short hard //both are zero, just mult ALO and BLO
-
- mov eax,ALO
- mul ecx
-
- ret 16 // callee restores the stack
-
-hard:
- push ebx
-
-// must redefine A and B since esp has been altered
-
-#define A2LO [esp + 8] // stack address of a
-#define A2HI [esp + 12] // stack address of a
-#define B2LO [esp + 16] // stack address of b
-#define B2HI [esp + 20] // stack address of b
-
- mul ecx //eax has AHI, ecx has BLO, so AHI * BLO
- mov ebx,eax //save result
-
- mov eax,A2LO
- mul dword ptr B2HI //ALO * BHI
- add ebx,eax //ebx = ((ALO * BHI) + (AHI * BLO))
-
- mov eax,A2LO //ecx = BLO
- mul ecx //so edx:eax = ALO*BLO
- add edx,ebx //now edx has all the LO*HI stuff
-
- pop ebx
-
- ret 16 // callee restores the stack
-
-END
projects / reactos.git / blobdiff