// Copyright (c) 1997-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// This component and the accompanying materials are made available
// under the terms of the License "Eclipse Public License v1.0"
// which accompanies this distribution, and is available
// at the URL "http://www.eclipse.org/legal/epl-v10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
// e32\euser\epoc\arm\uc_i64.cia
//
//
#include <u32std.h>
#include <e32math.h>
#if defined(__GCC32__)
extern "C" void __division_by_zero();
#define DIV_BY_ZERO " __division_by_zero "
#elif defined(__EABI__)
extern "C" void __rt_div0 (void);
#define DIV_BY_ZERO " __cpp(__rt_div0) "
#endif
EXPORT_C __NAKED__ void Math::Mul64(Int64 /*aX*/, Int64 /*aY*/, Int64& /*aOutH*/, Uint64& /*aOutL*/)
/**
Multiply aX by aY to generate a 128 bit result.
The high order 64 bits of this calculation are stored in aOutH,
and the low order 64 bits are stored in aOutL.
@param aX The first 64-bit operand.
@param aY The second 64-bit operand.
@param aOutH The high order 64 bits of the result.
@param aOutL The low order 64 bits of the result.
*/
{
// Enter with r1:r0=aX, r3:r2=aY, [sp]=&aOutH, [sp+4]=&aOutL
asm("stmfd sp!, {r4-r5,lr} ");
asm("umull r4, r5, r0, r2 "); // r5:r4 = x0 * y0
asm("mov r12, #0 "); // clear r12 initially
asm("umlal r5, r12, r0, r3 "); // r12:r5:r4 = x0 * y
asm("mov r14, #0 "); // clear r14 initially
asm("smlal r12, r14, r1, r3 "); // r14:r12:r5:r4 = x0 * y + (x1*y1)<<64
asm("and r3, r0, r3, asr #32 "); // if aY<0, r3=x0 else r3=0
asm("and r0, r2, r1, asr #32 "); // if aX<0, r0=y0 else r0=0
asm("subs r12, r12, r3 ");
asm("sbcs r14, r14, #0 ");
asm("subs r12, r12, r0 ");
asm("sbcs r14, r14, #0 ");
asm("umull r0, r3, r1, r2 "); // r3:r0 = x1 * y0
asm("ldr r1, [sp, #12] "); // r1=&aOutH
asm("ldr r2, [sp, #16] "); // r1=&aOutL
asm("adds r5, r5, r0 "); // shift left by 32 and add to give final result
asm("adcs r12, r12, r3 ");
asm("adcs r14, r14, #0 "); // final result now in r14:r12:r5:r4
asm("stmia r2, {r4,r5} "); // store low 64
asm("stmia r1, {r12,r14} "); // store high 64
__POPRET("r4-r5,");
}
EXPORT_C __NAKED__ void Math::UMul64(Uint64 /*aX*/, Uint64 /*aY*/, Uint64& /*aOutH*/, Uint64& /*aOutL*/)
/**
Multiply aX by aY to generate a 128 bit result.
The high order 64 bits of this calculation are stored in aOutH,
and the low order 64 bits are stored in aOutL.
@param aX The first 64-bit operand.
@param aY The second 64-bit operand.
@param aOutH The high order 64 bits of the result.
@param aOutL The low order 64 bits of the result.
*/
{
// Enter with r1:r0=aX, r3:r2=aY, [sp]=&aOutH, [sp+4]=&aOutL
asm("stmfd sp!, {r4-r5,lr} ");
asm("umull r4, r5, r0, r2 "); // r5:r4 = x0 * y0
asm("mov r12, #0 "); // clear r12 initially
asm("umlal r5, r12, r0, r3 "); // r12:r5:r4 = x0 * y
asm("mov r14, #0 "); // clear r14 initially
asm("umlal r12, r14, r1, r3 "); // r14:r12:r5:r4 = x0 * y + (x1*y1)<<64
// r0, r3 no longer required
asm("umull r0, r3, r1, r2 "); // r3:r0 = x1 * y0
asm("ldr r1, [sp, #12] "); // r1=&aOutH
asm("ldr r2, [sp, #16] "); // r1=&aOutL
asm("adds r5, r5, r0 "); // shift left by 32 and add to give final result
asm("adcs r12, r12, r3 ");
asm("adcs r14, r14, #0 "); // final result now in r14:r12:r5:r4
asm("stmia r2, {r4,r5} "); // store low 64
asm("stmia r1, {r12,r14} "); // store high 64
__POPRET("r4-r5,");
}
EXPORT_C __NAKED__ Int64 Math::DivMod64(Int64 /*aDividend*/, Int64 /*aDivisor*/, Int64& /*aRemainder*/)
/**
Divides aDividend by aDivisor.
The quotient is returned, and the remainder is stored in aRemainder.
The remainder has same sign as the dividend.
@param aDividend The 64-bit dividend.
@param aDivisor The 64-bit divisor.
@param aRemainder The 64-bit remainder.
@return The 64-bit quotient.
*/
{
// Enter with: r1:r0=dividend, r3:r2=divisor, [sp]=&aRemainder
// Return quotient in r1:r0
asm("stmfd sp!, {r4-r8,lr} ");
__EH_FRAME_PUSH2(r4-r8,lr)
asm("mov r8, r1, asr #1 "); // r8 bit 31 = r8 bit 30 = dividend sign
asm("eor r8, r8, r3, lsr #1 "); // r8 bit 31 = dividend sign, r8 bit 30 = quotient sign
asm("cmp r1, #0 ");
asm("bpl 1f ");
asm("rsbs r0, r0, #0 "); // r1:r0=ABS(dividend)
asm("rscs r1, r1, #0 ");
asm("1: ");
asm("cmp r3, #0 ");
asm("bpl 2f ");
asm("rsbs r2, r2, #0 "); // r3:r2=ABS(divisor)
asm("rscs r3, r3, #0 ");
asm("2: ");
#ifndef __EABI__
asm(".extern UDiv01 ");
asm("bl UDiv01 "); // do division, quotient->r5:r4, rem->r6:r3
asm("mov r2, r3"); // move to make regs same as EABI function
asm("mov r0, r4");
asm("mov r1, r5");
asm("mov r3, r6");
#else //__EABI__
asm(".extern __aeabi_uldivmod ");
asm("bl __aeabi_uldivmod "); // do division, quotient->r1:r0, rem->r3:r2
#endif //__EABI__
asm("add ip, r8, r8 "); // ip bit 31 = quotient sign
asm("ldr r6, [sp, #24] "); // r6 = &aRemainder
asm("eors r4, r0, ip, asr #32 "); // quotient into r5:r4, inverted if quotient -ve
asm("eors r5, r1, ip, asr #32 ");
asm("adcs r0, r4, #0 "); // if quotient -ve, add 1 whilst moving back to r1:r0
asm("adcs r1, r5, #0 ");
asm("cmp r8, #0 ");
asm("bpl 3f ");
asm("rsbs r2, r2, #0 "); // if dividend -ve, negate remainder
asm("rscs r3, r3, #0 ");
asm("3: ");
asm("stmia r6, {r2,r3} "); // store remainder
__POPRET("r4-r8,");
}
EXPORT_C __NAKED__ Uint64 Math::UDivMod64(Uint64 /*aDividend*/, Uint64 /*aDivisor*/, Uint64& /*aRemainder*/)
/**
Divides aDividend by aDivisor.
The quotient is returned, and the remainder is stored in aRemainder.
@param aDividend The 64-bit dividend.
@param aDivisor The 64-bit divisor.
@param aRemainder The 64-bit remainder.
@return The 64-bit quotient.
*/
{
// Enter with: r1:r0=dividend, r3:r2=divisor, [sp]=&aRemainder
// Return quotient in r1:r0
#ifdef __EABI__
// need to keep sp 8-byte aligned
asm("stmfd sp!, {r4-r8,lr} ");
__EH_FRAME_PUSH2(r4-r8,lr)
#else
asm("stmfd sp!, {r4-r7,lr} ");
#endif
#ifndef __EABI__
asm(".extern UDiv01 ");
asm("bl UDiv01 "); // do division, quotient->r5:r4, rem->r6:r3
asm("mov r2, r3"); // move to make regs same as EABI function
asm("mov r0, r4");
asm("mov r1, r5");
asm("mov r3, r6");
#else //__EABI__
asm("bl __aeabi_uldivmod "); // do division, quotient->r1:r0, rem->r3:r2
#endif //__EABI__
#ifdef __EABI__
asm("ldr r6, [sp, #24] "); // r6 = &aRemainder
#else
asm("ldr r6, [sp, #20] "); // r6 = &aRemainder
#endif
asm("stmia r6, {r2,r3} "); // store remainder
#ifdef __EABI__
__POPRET("r4-r8,");
#else
__POPRET("r4-r7,");
#endif
}