dolphin/Source/Core/DSPCore/Src/DspIntMultiplier.cpp

554 lines
15 KiB
C++

// Copyright (C) 2003 Dolphin Project.
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License 2.0 for more details.
// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/
// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/
// Additional copyrights go to Duddie and Tratax (c) 2004
// Multiplier and product register control
#include "DSPInterpreter.h"
#include "DSPIntCCUtil.h"
#include "DSPIntUtil.h"
namespace DSPInterpreter {
// Only MULX family instructions have unsigned support.
inline s64 dsp_get_multiply_prod(u16 a, u16 b, bool sign)
{
s64 prod;
if (sign && g_dsp.r[DSP_REG_SR] & SR_MUL_UNSIGNED)
prod = (u64)a * (u64)b; // won't overflow 32-bits
else
prod = (s32)(s16)a * (s32)(s16)b; // won't overflow 32-bits
// Conditionally multiply by 2.
if ((g_dsp.r[DSP_REG_SR] & SR_MUL_MODIFY) == 0)
prod <<= 1;
return prod;
}
// Sets prod as a side effect.
s64 dsp_multiply(u16 a, u16 b, bool sign = false)
{
s64 prod = dsp_get_multiply_prod(a, b, sign);
// Store the product, and return it, in case the caller wants to read it.
// dsp_set_long_prod(prod);
return prod;
}
s64 dsp_multiply_add(u16 a, u16 b, bool sign = false)
{
s64 prod = dsp_get_multiply_prod(a, b, sign) + dsp_get_long_prod();
// Store the product, and return it, in case the caller wants to read it.
// dsp_set_long_prod(prod);
return prod;
}
s64 dsp_multiply_sub(u16 a, u16 b, bool sign = false)
{
s64 prod = dsp_get_long_prod() - dsp_get_multiply_prod(a, b, sign);
// Store the product, and return it, in case the caller wants to read it.
// dsp_set_long_prod(prod);
return prod;
}
// CLRP
// 1000 0100 xxxx xxxx
// Clears product register $prod.
void clrp(const UDSPInstruction& opc)
{
// Magic numbers taken from duddie's doc
// These are probably a bad idea to put here.
zeroWriteBackLog();
g_dsp.r[0x14] = 0x0000;
g_dsp.r[0x15] = 0xfff0;
g_dsp.r[0x16] = 0x00ff;
g_dsp.r[0x17] = 0x0010;
}
// MOVP $acD
// 0110 111d xxxx xxxx
// Moves multiply product from $prod register to accumulator $acD register.
void movp(const UDSPInstruction& opc)
{
u8 dreg = (opc.hex >> 8) & 0x1;
s64 prod = dsp_get_long_prod();
zeroWriteBackLog();
dsp_set_long_acc(dreg, prod);
Update_SR_Register64(prod);
}
// MOVNP $acD
// 0111 111d xxxx xxxx
// Moves negative of multiply product from $prod register to accumulator
// $acD register.
void movnp(const UDSPInstruction& opc)
{
u8 dreg = (opc.hex >> 8) & 0x1;
s64 prod = dsp_get_long_prod();
s64 acc = -prod;
zeroWriteBackLog();
dsp_set_long_acc(dreg, acc);
Update_SR_Register64(acc);
}
// ADDPAXZ $acD, $axS
// 1111 10sd xxxx xxxx
// Adds secondary accumulator $axS to product register and stores result
// in accumulator register. Low 16-bits of $acD ($acD.l) are set to 0.
void addpaxz(const UDSPInstruction& opc)
{
u8 dreg = (opc.hex >> 8) & 0x1;
u8 sreg = (opc.hex >> 9) & 0x1;
s64 prod = dsp_get_long_prod() & ~0xffff; // hm, should we really mask here?
s64 ax = dsp_get_long_acx(sreg);
s64 acc = (prod + ax) & ~0xffff;
zeroWriteBackLog();
dsp_set_long_acc(dreg, acc);
Update_SR_Register64(acc);
}
// MOVPZ $acD
// 1111 111d xxxx xxxx
// Moves multiply product from $prod register to accumulator $acD
// register and sets $acD.l to 0
void movpz(const UDSPInstruction& opc)
{
u8 dreg = (opc.hex >> 8) & 0x01;
// overwrite acc and clear low part
s64 prod = dsp_get_long_prod();
s64 acc = prod & ~0xffff;
zeroWriteBackLog();
dsp_set_long_acc(dreg, acc);
Update_SR_Register64(acc);
}
// MULC $acS.m, $axT.h
// 110s t000 xxxx xxxx
// Multiply mid part of accumulator register $acS.m by high part $axS.h of
// secondary accumulator $axS (treat them both as signed).
void mulc(const UDSPInstruction& opc)
{
u8 sreg = (opc.hex >> 11) & 0x1;
u8 treg = (opc.hex >> 12) & 0x1;
u16 accm = dsp_get_acc_m(sreg);
u16 axh = dsp_get_ax_h(treg);
s64 prod = dsp_multiply(accm, axh);
zeroWriteBackLog();
dsp_set_long_prod(prod);
Update_SR_Register64(prod);
}
// MULCMVZ $acS.m, $axT.h, $acR
// 110s t01r xxxx xxxx
// (fixed possible bug in duddie's description, s->t)
// Multiply mid part of accumulator register $acS.m by high part $axT.h of
// secondary accumulator $axT (treat them both as signed). Move product
// register before multiplication to accumulator $acR, set low part of
// accumulator $acR.l to zero.
void mulcmvz(const UDSPInstruction& opc)
{
s64 TempProd = dsp_get_long_prod();
// update prod
u8 sreg = (opc.hex >> 12) & 0x1;
u8 treg = (opc.hex >> 11) & 0x1;
u16 accm = dsp_get_acc_m(sreg);
u16 axh = dsp_get_ax_h(treg);
s64 prod = dsp_multiply(accm, axh);
zeroWriteBackLog();
dsp_set_long_prod(prod);
// update acc
u8 rreg = (opc.hex >> 8) & 0x1;
s64 acc = TempProd & ~0xffff; // clear lower 4 bytes
dsp_set_long_acc(rreg, acc);
Update_SR_Register64(acc);
}
// MULCMV $acS.m, $axT.h, $acR
// 110s t11r xxxx xxxx
// Multiply mid part of accumulator register $acS.m by high part $axT.h of
// secondary accumulator $axT (treat them both as signed). Move product
// register before multiplication to accumulator $acR.
// possible mistake in duddie's doc axT.h rather than axS.h
void mulcmv(const UDSPInstruction& opc)
{
s64 old_prod = dsp_get_long_prod();
// update prod
u8 sreg = (opc.hex >> 12) & 0x1;
u8 treg = (opc.hex >> 11) & 0x1;
u16 accm = dsp_get_acc_m(sreg);
u16 axh = dsp_get_ax_h(treg);
u8 rreg = (opc.hex >> 8) & 0x1;
s64 prod = dsp_multiply(accm, axh);
zeroWriteBackLog();
dsp_set_long_prod(prod);
// update acc
dsp_set_long_acc(rreg, old_prod);
Update_SR_Register64(old_prod);
}
// MULCAC $acS.m, $axT.h, $acR
// 110s t10r xxxx xxxx
// Multiply mid part of accumulator register $acS.m by high part $axS.h of
// secondary accumulator $axS (treat them both as signed). Add product
// register before multiplication to accumulator $acR.
void mulcac(const UDSPInstruction& opc)
{
s64 old_prod = dsp_get_long_prod();
// update prod
u8 sreg = (opc.hex >> 12) & 0x1;
u8 treg = (opc.hex >> 11) & 0x1;
u16 accm = dsp_get_acc_m(sreg);
u16 axh = dsp_get_ax_h(treg);
s64 prod = dsp_multiply(accm, axh);
u8 rreg = (opc.hex >> 8) & 0x1;
s64 acc = old_prod + dsp_get_long_acc(rreg);
zeroWriteBackLog();
dsp_set_long_prod(prod);
// update acc
dsp_set_long_acc(rreg, acc);
Update_SR_Register64(acc);
}
// MUL $axS.l, $axS.h
// 1001 s000 xxxx xxxx
// Multiply low part $axS.l of secondary accumulator $axS by high part
// $axS.h of secondary accumulator $axS (treat them both as signed).
void mul(const UDSPInstruction& opc)
{
u8 sreg = (opc.hex >> 11) & 0x1;
u16 axl = dsp_get_ax_l(sreg);
u16 axh = dsp_get_ax_h(sreg);
s64 prod = dsp_multiply(axh, axl);
zeroWriteBackLog();
dsp_set_long_prod(prod);
// FIXME: no update in duddie's docs
Update_SR_Register64(prod);
}
// MULAC $axS.l, $axS.h, $acR
// 1001 s10r xxxx xxxx
// Add product register to accumulator register $acR. Multiply low part
// $axS.l of secondary accumulator $axS by high part $axS.h of secondary
// accumulator $axS (treat them both as signed).
void mulac(const UDSPInstruction& opc)
{
// add old prod to acc
u8 rreg = (opc.hex >> 8) & 0x1;
u8 sreg = (opc.hex >> 11) & 0x1;
s64 acR = dsp_get_long_acc(rreg) + dsp_get_long_prod();
u16 axl = dsp_get_ax_l(sreg);
u16 axh = dsp_get_ax_h(sreg);
s64 prod = dsp_multiply(axl, axh);
zeroWriteBackLog();
dsp_set_long_acc(rreg, acR);
dsp_set_long_prod(prod);
// FIXME: no update in duddie's docs
Update_SR_Register64(prod);
}
// MULMV $axS.l, $axS.h, $acR
// 1001 s11r xxxx xxxx
// Move product register to accumulator register $acR. Multiply low part
// $axS.l of secondary accumulator $axS by high part $axS.h of secondary
// accumulator $axS (treat them both as signed).
void mulmv(const UDSPInstruction& opc)
{
u8 rreg = (opc.hex >> 8) & 0x1;
u8 sreg = ((opc.hex >> 11) & 0x1);
s64 acc = dsp_get_long_prod();
u16 axl = dsp_get_ax_l(sreg);
u16 axh = dsp_get_ax_h(sreg);
s64 prod = dsp_multiply(axl, axh);
zeroWriteBackLog();
dsp_set_long_acc(rreg, acc);
dsp_set_long_prod(prod);
Update_SR_Register64(prod);
}
// MULMVZ $axS.l, $axS.h, $acR
// 1001 s01r xxxx xxxx
// Move product register to accumulator register $acR and clear low part
// of accumulator register $acR.l. Multiply low part $axS.l of secondary
// accumulator $axS by high part $axS.h of secondary accumulator $axS (treat
// them both as signed).
void mulmvz(const UDSPInstruction& opc)
{
u8 sreg = (opc.hex >> 11) & 0x1;
u8 rreg = (opc.hex >> 8) & 0x1;
// overwrite acc and clear low part
s64 acc = dsp_get_long_prod() & ~0xffff;
u16 axl = dsp_get_ax_l(sreg);
u16 axh = dsp_get_ax_h(sreg);
s64 prod = dsp_multiply(axl, axh);
zeroWriteBackLog();
dsp_set_long_acc(rreg, acc);
dsp_set_long_prod(prod);
Update_SR_Register64(prod);
}
// MULX $ax0.S, $ax1.T
// 101s t000 xxxx xxxx
// Multiply one part $ax0 by one part $ax1 (treat them both as signed).
// Part is selected by S and T bits. Zero selects low part, one selects high part.
void mulx(const UDSPInstruction& opc)
{
u8 sreg = ((opc.hex >> 12) & 0x1);
u8 treg = ((opc.hex >> 11) & 0x1);
u16 val1 = (sreg == 0) ? dsp_get_ax_l(0) : dsp_get_ax_h(0);
u16 val2 = (treg == 0) ? dsp_get_ax_l(1) : dsp_get_ax_h(1);
s64 prod = dsp_multiply(val1, val2, true);
zeroWriteBackLog();
dsp_set_long_prod(prod);
Update_SR_Register64(prod);
}
// MULXAC $ax0.S, $ax1.T, $acR
// 101s t01r xxxx xxxx
// Add product register to accumulator register $acR. Multiply one part
// $ax0 by one part $ax1 (treat them both as signed). Part is selected by S and
// T bits. Zero selects low part, one selects high part.
void mulxac(const UDSPInstruction& opc)
{
// add old prod to acc
u8 rreg = (opc.hex >> 8) & 0x1;
s64 acR = dsp_get_long_acc(rreg) + dsp_get_long_prod();
// math new prod
u8 sreg = (opc.hex >> 12) & 0x1;
u8 treg = (opc.hex >> 11) & 0x1;
u16 val1 = (sreg == 0) ? dsp_get_ax_l(0) : dsp_get_ax_h(0);
u16 val2 = (treg == 0) ? dsp_get_ax_l(1) : dsp_get_ax_h(1);
s64 prod = dsp_multiply(val1, val2, true);
zeroWriteBackLog();
dsp_set_long_acc(rreg, acR);
dsp_set_long_prod(prod);
Update_SR_Register64(prod);
}
// MULXMV $ax0.S, $ax1.T, $acR
// 101s t11r xxxx xxxx
// Move product register to accumulator register $acR. Multiply one part
// $ax0 by one part $ax1 (treat them both as signed). Part is selected by S and
// T bits. Zero selects low part, one selects high part.
void mulxmv(const UDSPInstruction& opc)
{
// add old prod to acc
u8 rreg = ((opc.hex >> 8) & 0x1);
s64 acR = dsp_get_long_prod();
// math new prod
u8 sreg = (opc.hex >> 12) & 0x1;
u8 treg = (opc.hex >> 11) & 0x1;
s16 val1 = (sreg == 0) ? dsp_get_ax_l(0) : dsp_get_ax_h(0);
s16 val2 = (treg == 0) ? dsp_get_ax_l(1) : dsp_get_ax_h(1);
s64 prod = dsp_multiply(val1, val2, true);
zeroWriteBackLog();
dsp_set_long_acc(rreg, acR);
dsp_set_long_prod(prod);
Update_SR_Register64(prod);
}
// MULXMV $ax0.S, $ax1.T, $acR
// 101s t01r xxxx xxxx
// Move product register to accumulator register $acR and clear low part
// of accumulator register $acR.l. Multiply one part $ax0 by one part $ax1 (treat
// them both as signed). Part is selected by S and T bits. Zero selects low part,
// one selects high part.
void mulxmvz(const UDSPInstruction& opc)
{
// overwrite acc and clear low part
u8 rreg = (opc.hex >> 8) & 0x1;
s64 acc = dsp_get_long_prod() & ~0xffff;
// math prod
u8 sreg = (opc.hex >> 12) & 0x1;
u8 treg = (opc.hex >> 11) & 0x1;
u16 val1 = (sreg == 0) ? dsp_get_ax_l(0) : dsp_get_ax_h(0);
u16 val2 = (treg == 0) ? dsp_get_ax_l(1) : dsp_get_ax_h(1);
s64 prod = dsp_multiply(val1, val2, true);
zeroWriteBackLog();
dsp_set_long_acc(rreg, acc);
dsp_set_long_prod(prod);
Update_SR_Register64(prod);
}
// MADDX ax0.S ax1.T
// 1110 00st xxxx xxxx
// Multiply one part of secondary accumulator $ax0 (selected by S) by
// one part of secondary accumulator $ax1 (selected by T) (treat them both as
// signed) and add result to product register.
void maddx(const UDSPInstruction& opc)
{
u8 sreg = (opc.hex >> 9) & 0x1;
u8 treg = (opc.hex >> 8) & 0x1;
u16 val1 = (sreg == 0) ? dsp_get_ax_l(0) : dsp_get_ax_h(0);
u16 val2 = (treg == 0) ? dsp_get_ax_l(1) : dsp_get_ax_h(1);
s64 prod = dsp_multiply_add(val1, val2, true);
zeroWriteBackLog();
dsp_set_long_prod(prod);
Update_SR_Register64(prod);
}
// MSUBX $(0x18+S*2), $(0x19+T*2)
// 1110 01st xxxx xxxx
// Multiply one part of secondary accumulator $ax0 (selected by S) by
// one part of secondary accumulator $ax1 (selected by T) (treat them both as
// signed) and subtract result from product register.
void msubx(const UDSPInstruction& opc)
{
u8 sreg = (opc.hex >> 9) & 0x1;
u8 treg = (opc.hex >> 8) & 0x1;
u16 val1 = (sreg == 0) ? dsp_get_ax_l(0) : dsp_get_ax_h(0);
u16 val2 = (treg == 0) ? dsp_get_ax_l(1) : dsp_get_ax_h(1);
s64 prod = dsp_multiply_sub(val1, val2, true);
zeroWriteBackLog();
dsp_set_long_prod(prod);
Update_SR_Register64(prod);
}
// MADDC $acS.m, $axT.h
// 1110 10st xxxx xxxx
// Multiply middle part of accumulator $acS.m by high part of secondary
// accumulator $axT.h (treat them both as signed) and add result to product
// register.
void maddc(const UDSPInstruction& opc)
{
u32 sreg = (opc.hex >> 9) & 0x1;
u32 treg = (opc.hex >> 8) & 0x1;
u16 accm = dsp_get_acc_m(sreg);
u16 axh = dsp_get_ax_h(treg);
s64 prod = dsp_multiply_add(accm, axh);
zeroWriteBackLog();
dsp_set_long_prod(prod);
Update_SR_Register64(prod);
}
// MSUBC $acS.m, $axT.h
// 1110 11st xxxx xxxx
// Multiply middle part of accumulator $acS.m by high part of secondary
// accumulator $axT.h (treat them both as signed) and subtract result from
// product register.
void msubc(const UDSPInstruction& opc)
{
u32 sreg = (opc.hex >> 9) & 0x1;
u32 treg = (opc.hex >> 8) & 0x1;
u16 accm = dsp_get_acc_m(sreg);
u16 axh = dsp_get_ax_h(treg);
s64 prod = dsp_multiply_sub(accm, axh);
zeroWriteBackLog();
dsp_set_long_prod(prod);
Update_SR_Register64(prod);
}
// MADD $axS.l, $axS.h
// 1111 001s xxxx xxxx
// Multiply low part $axS.l of secondary accumulator $axS by high part
// $axS.h of secondary accumulator $axS (treat them both as signed) and add
// result to product register.
void madd(const UDSPInstruction& opc)
{
u8 sreg = (opc.hex >> 8) & 0x1;
u16 axl = dsp_get_ax_l(sreg);
u16 axh = dsp_get_ax_h(sreg);
s64 prod = dsp_multiply_add(axl, axh);
zeroWriteBackLog();
dsp_set_long_prod(prod);
Update_SR_Register64(prod);
}
// MSUB $axS.l, $axS.h
// 1111 011s xxxx xxxx
// Multiply low part $axS.l of secondary accumulator $axS by high part
// $axS.h of secondary accumulator $axS (treat them both as signed) and
// subtract result from product register.
void msub(const UDSPInstruction& opc)
{
u8 sreg = (opc.hex >> 8) & 0x1;
u16 axl = dsp_get_ax_l(sreg);
u16 axh = dsp_get_ax_h(sreg);
s64 prod = dsp_multiply_sub(axl, axh);
zeroWriteBackLog();
dsp_set_long_prod(prod);
Update_SR_Register64(prod);
}
} // namespace