From e4dc1dc22dafd6d65f45843b1b7447edb058cdda Mon Sep 17 00:00:00 2001 From: Alex Ionescu Date: Mon, 26 Sep 2005 21:39:04 +0000 Subject: [PATCH] - Implement alldvrm and aulldvrm and export them from ntoskrnl. This fixes bug 467. svn path=/trunk/; revision=18110 --- reactos/lib/rtl/i386/math.S | 396 +++++++++++++++++++++++++++++++++- reactos/ntoskrnl/ntoskrnl.def | 2 + 2 files changed, 397 insertions(+), 1 deletion(-) diff --git a/reactos/lib/rtl/i386/math.S b/reactos/lib/rtl/i386/math.S index f41965817af..ca1d6caf6eb 100644 --- a/reactos/lib/rtl/i386/math.S +++ b/reactos/lib/rtl/i386/math.S @@ -5,7 +5,34 @@ * FILE: lib/rtl/i386/math.S * PROGRAMER: Alex Ionescu (alex@relsoft.net) * Eric Kohl (ekohl@rz-online.de) - * REVISION HISTORY: 27/07/2005 Created + * + * 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. */ /* GLOBALS ****************************************************************/ @@ -19,6 +46,8 @@ .globl __aullrem .globl __allmul .globl __alldiv +.globl __aulldvrm +.globl __alldvrm /* FUNCTIONS ***************************************************************/ @@ -235,3 +264,368 @@ __ftol: /* Remove stack frame and return*/ leave ret + +__alldvrm: + push edi + push esi + push ebp + +// Set up the local stack and save the index registers. When this is done +// the stack frame will look as follows (assuming that the expression a/b will +// generate a call to alldvrm(a, b)): +// +// ----------------- +// | | +// |---------------| +// | | +// |--divisor (b)--| +// | | +// |---------------| +// | | +// |--dividend (a)-| +// | | +// |---------------| +// | return addr** | +// |---------------| +// | EDI | +// |---------------| +// | ESI | +// |---------------| +// ESP---->| EBP | +// ----------------- +// + +#define DVNDLO [esp + 16] // stack address of dividend (a) +#define DVNDHI [esp + 20] // stack address of dividend (a) +#define DVSRLO [esp + 24] // stack address of divisor (b) +#define DVSRHI [esp + 28] // stack address of divisor (b) + +// Determine sign of the quotient (edi = 0 if result is positive, non-zero +// otherwise) and make operands positive. +// Sign of the remainder is kept in ebp. + + xor edi,edi // result sign assumed positive + xor ebp,ebp // result sign assumed positive + + mov eax,DVNDHI // hi word of a + or eax,eax // test to see if signed + jge short L1 // skip rest if a is already positive + inc edi // complement result sign flag + inc ebp // complement result sign flag + mov edx,DVNDLO // lo word of a + neg eax // make a positive + neg edx + sbb eax,0 + mov DVNDHI,eax // save positive value + mov DVNDLO,edx +L1: + mov eax,DVSRHI // hi word of b + or eax,eax // test to see if signed + jge short L2 // skip rest if b is already positive + inc edi // complement the result sign flag + mov edx,DVSRLO // lo word of a + neg eax // make b positive + neg edx + sbb eax,0 + mov DVSRHI,eax // save positive value + mov DVSRLO,edx +L2: + +// +// Now do the divide. First look to see if the divisor is less than 4194304K. +// If so, then we can use a simple algorithm with word divides, otherwise +// things get a little more complex. +// +// NOTE - eax currently contains the high order word of DVSR +// + + or eax,eax // check to see if divisor < 4194304K + jnz short L3 // nope, gotta do this the hard way + mov ecx,DVSRLO // load divisor + mov eax,DVNDHI // load high word of dividend + xor edx,edx + div ecx // eax <- high order bits of quotient + mov ebx,eax // save high bits of quotient + mov eax,DVNDLO // edx:eax <- remainder:lo word of dividend + div ecx // eax <- low order bits of quotient + mov esi,eax // ebx:esi <- quotient +// +// Now we need to do a multiply so that we can compute the remainder. +// + mov eax,ebx // set up high word of quotient + mul dword ptr DVSRLO // HIWORD(QUOT) * DVSR + mov ecx,eax // save the result in ecx + mov eax,esi // set up low word of quotient + mul dword ptr DVSRLO // LOWORD(QUOT) * DVSR + add edx,ecx // EDX:EAX = QUOT * DVSR + jmp short L4 // complete remainder calculation + +// +// Here we do it the hard way. Remember, eax contains the high word of DVSR +// + +L3: + mov ebx,eax // ebx:ecx <- divisor + mov ecx,DVSRLO + mov edx,DVNDHI // edx:eax <- dividend + mov eax,DVNDLO +L5: + shr ebx,1 // shift divisor right one bit + rcr ecx,1 + shr edx,1 // shift dividend right one bit + rcr eax,1 + or ebx,ebx + jnz short L5 // loop until divisor < 4194304K + div ecx // now divide, ignore remainder + mov esi,eax // save quotient + +// +// We may be off by one, so to check, we will multiply the quotient +// by the divisor and check the result against the orignal dividend +// Note that we must also check for overflow, which can occur if the +// dividend is close to 2**64 and the quotient is off by 1. +// + + mul dword ptr DVSRHI // QUOT * DVSRHI + mov ecx,eax + mov eax,DVSRLO + mul esi // QUOT * DVSRLO + add edx,ecx // EDX:EAX = QUOT * DVSR + jc short L6 // carry means Quotient is off by 1 + +// +// do long compare here between original dividend and the result of the +// multiply in edx:eax. If original is larger or equal, we are ok, otherwise +// subtract one (1) from the quotient. +// + + cmp edx,DVNDHI // compare hi words of result and original + ja short L6 // if result > original, do subtract + jb short L7 // if result < original, we are ok + cmp eax,DVNDLO // hi words are equal, compare lo words + jbe short L7 // if less or equal we are ok, else subtract +L6: + dec esi // subtract 1 from quotient + sub eax,DVSRLO // subtract divisor from result + sbb edx,DVSRHI +L7: + xor ebx,ebx // ebx:esi <- quotient + +L4: +// +// Calculate remainder by subtracting the result from the original dividend. +// Since the result is already in a register, we will do the subtract in the +// opposite direction and negate the result if necessary. +// + + sub eax,DVNDLO // subtract dividend from result + sbb edx,DVNDHI + +// +// Now check the result sign flag to see if the result is supposed to be positive +// or negative. It is currently negated (because we subtracted in the 'wrong' +// direction), so if the sign flag is set we are done, otherwise we must negate +// the result to make it positive again. +// + + dec ebp // check result sign flag + jns short L9 // result is ok, set up the quotient + neg edx // otherwise, negate the result + neg eax + sbb edx,0 + +// +// Now we need to get the quotient into edx:eax and the remainder into ebx:ecx. +// +L9: + mov ecx,edx + mov edx,ebx + mov ebx,ecx + mov ecx,eax + mov eax,esi + +// +// Just the cleanup left to do. edx:eax contains the quotient. Set the sign +// according to the save value, cleanup the stack, and return. +// + + dec edi // check to see if result is negative + jnz short L8 // if EDI == 0, result should be negative + neg edx // otherwise, negate the result + neg eax + sbb edx,0 + +// +// Restore the saved registers and return. +// + +L8: + pop ebp + pop esi + pop edi + + ret 16 + +__aulldvrm: + +// ulldvrm - unsigned long divide and remainder +// +// Purpose: +// Does a unsigned long divide and remainder of the arguments. Arguments +// are not changed. +// +// Entry: +// Arguments are passed on the stack: +// 1st pushed: divisor (QWORD) +// 2nd pushed: dividend (QWORD) +// +// Exit: +// EDX:EAX contains the quotient (dividend/divisor) +// EBX:ECX contains the remainder (divided % divisor) +// NOTE: this routine removes the parameters from the stack. +// +// Uses: +// ECX +// + push esi + +// Set up the local stack and save the index registers. When this is done +// the stack frame will look as follows (assuming that the expression a/b will +// generate a call to aulldvrm(a, b)): +// +// ----------------- +// | | +// |---------------| +// | | +// |--divisor (b)--| +// | | +// |---------------| +// | | +// |--dividend (a)-| +// | | +// |---------------| +// | return addr** | +// |---------------| +// ESP---->| ESI | +// ----------------- +// + +#undef DVNDLO +#undef DVNDHI +#undef DVSRLO +#undef DVSRHI +#define DVNDLO [esp + 8] // stack address of dividend (a) +#define DVNDHI [esp + 8] // stack address of dividend (a) +#define DVSRLO [esp + 16] // stack address of divisor (b) +#define DVSRHI [esp + 20] // stack address of divisor (b) + +// +// Now do the divide. First look to see if the divisor is less than 4194304K. +// If so, then we can use a simple algorithm with word divides, otherwise +// things get a little more complex. +// + + mov eax,DVSRHI // check to see if divisor < 4194304K + or eax,eax + jnz short .L1 // nope, gotta do this the hard way + mov ecx,DVSRLO // load divisor + mov eax,DVNDHI // load high word of dividend + xor edx,edx + div ecx // get high order bits of quotient + mov ebx,eax // save high bits of quotient + mov eax,DVNDLO // edx:eax <- remainder:lo word of dividend + div ecx // get low order bits of quotient + mov esi,eax // ebx:esi <- quotient + +// +// Now we need to do a multiply so that we can compute the remainder. +// + mov eax,ebx // set up high word of quotient + mul dword ptr DVSRLO // HIWORD(QUOT) * DVSR + mov ecx,eax // save the result in ecx + mov eax,esi // set up low word of quotient + mul dword ptr DVSRLO // LOWORD(QUOT) * DVSR + add edx,ecx // EDX:EAX = QUOT * DVSR + jmp short .L2 // complete remainder calculation + +// +// Here we do it the hard way. Remember, eax contains DVSRHI +// + +.L1: + mov ecx,eax // ecx:ebx <- divisor + mov ebx,DVSRLO + mov edx,DVNDHI // edx:eax <- dividend + mov eax,DVNDLO +.L3: + shr ecx,1 // shift divisor right one bit// hi bit <- 0 + rcr ebx,1 + shr edx,1 // shift dividend right one bit// hi bit <- 0 + rcr eax,1 + or ecx,ecx + jnz short .L3 // loop until divisor < 4194304K + div ebx // now divide, ignore remainder + mov esi,eax // save quotient + +// +// We may be off by one, so to check, we will multiply the quotient +// by the divisor and check the result against the orignal dividend +// Note that we must also check for overflow, which can occur if the +// dividend is close to 2**64 and the quotient is off by 1. +// + + mul dword ptr DVSRHI // QUOT * DVSRHI + mov ecx,eax + mov eax,DVSRLO + mul esi // QUOT * DVSRLO + add edx,ecx // EDX:EAX = QUOT * DVSR + jc short .L4 // carry means Quotient is off by 1 + +// +// do long compare here between original dividend and the result of the +// multiply in edx:eax. If original is larger or equal, we are ok, otherwise +// subtract one (1) from the quotient. +// + + cmp edx,DVNDHI // compare hi words of result and original + ja short .L4 // if result > original, do subtract + jb short .L5 // if result < original, we are ok + cmp eax,DVNDLO // hi words are equal, compare lo words + jbe short .L5 // if less or equal we are ok, else subtract +.L4: + dec esi // subtract 1 from quotient + sub eax,DVSRLO // subtract divisor from result + sbb edx,DVSRHI +.L5: + xor ebx,ebx // ebx:esi <- quotient + +.L2: +// +// Calculate remainder by subtracting the result from the original dividend. +// Since the result is already in a register, we will do the subtract in the +// opposite direction and negate the result. +// + + sub eax,DVNDLO // subtract dividend from result + sbb edx,DVNDHI + neg edx // otherwise, negate the result + neg eax + sbb edx,0 + +// +// Now we need to get the quotient into edx:eax and the remainder into ebx:ecx. +// + mov ecx,edx + mov edx,ebx + mov ebx,ecx + mov ecx,eax + mov eax,esi +// +// Just the cleanup left to do. edx:eax contains the quotient. +// Restore the saved registers and return. +// + + pop esi + + ret 16 + diff --git a/reactos/ntoskrnl/ntoskrnl.def b/reactos/ntoskrnl/ntoskrnl.def index 993dfe62a12..17ee641ce2b 100644 --- a/reactos/ntoskrnl/ntoskrnl.def +++ b/reactos/ntoskrnl/ntoskrnl.def @@ -1411,7 +1411,9 @@ _alloca_probe _allrem _allshl _allshr +_alldvrm _aulldiv +_aulldvrm _aullrem _aullshr _except_handler2 -- 2.17.1