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DSP: Further disasm improvements. Make a few mul ops (only two of which I have seen, both in Zelda) behave like Duddie's doc says they should.

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git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@2941 8ced0084-cf51-0410-be5f-012b33b47a6e
This commit is contained in:
hrydgard
2009-04-09 14:33:34 +00:00
parent 0f26228ef2
commit 5166251b2c
6 changed files with 55 additions and 34 deletions
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37
Source/Plugins/Plugin_DSP_LLE/Src/DSPInterpreter.cpp
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@ -589,14 +589,21 @@ void mulc(const UDSPInstruction& opc)
Update_SR_Register64(prod);
}
// MULCMVZ
// 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;
s64 Prod = (s64)dsp_get_acc_m(sreg) * (s64)dsp_get_acc_h(sreg) * GetMultiplyModifier();
u8 treg = (opc.hex >> 11) & 0x1;
s64 Prod = (s64)dsp_get_acc_m(sreg) * (s64)dsp_get_ax_h(treg) * GetMultiplyModifier();
dsp_set_long_prod(Prod);
// update acc
@ -607,13 +614,19 @@ void mulcmvz(const UDSPInstruction& opc)
Update_SR_Register64(acc);
}
// MULCMV
// 110s t11r xxxx xxxx
// Multiply mid part of accumulator register $acS.m by high part $axS.h of
// secondary accumulator $axT (treat them both as signed). Move product
// register before multiplication to accumulator $acR.
void mulcmv(const UDSPInstruction& opc)
{
s64 TempProd = dsp_get_long_prod();
// update prod
u8 sreg = (opc.hex >> 12) & 0x1;
s64 Prod = (s64)dsp_get_acc_m(sreg) * (s64)dsp_get_acc_h(sreg) * GetMultiplyModifier();
u8 treg = (opc.hex >> 11) & 0x1;
s64 Prod = (s64)dsp_get_acc_m(sreg) * (s64)dsp_get_ax_h(sreg) * GetMultiplyModifier();
dsp_set_long_prod(Prod);
// update acc
@ -623,6 +636,8 @@ void mulcmv(const UDSPInstruction& opc)
Update_SR_Register64(TempProd);
}
// CMPAR
// Not described by Duddie's doc - at least not as a separate instruction.
void cmpar(const UDSPInstruction& opc)
{
u8 rreg = ((opc.hex >> 12) & 0x1) + 0x1a;
@ -637,6 +652,9 @@ void cmpar(const UDSPInstruction& opc)
Update_SR_Register64(ar - rr);
}
// CMP
// 1000 0010 xxxx xxxx
// Compares accumulator $ac0 with accumulator $ac1.
void cmp(const UDSPInstruction& opc)
{
s64 acc0 = dsp_get_long_acc(0);
@ -645,6 +663,9 @@ void cmp(const UDSPInstruction& opc)
Update_SR_Register64(acc0 - acc1);
}
// TST
// 1011 r001 xxxx xxxx
// Test accumulator %acR.
void tst(const UDSPInstruction& opc)
{
tsta((opc.hex >> 11) & 0x1);
@ -679,18 +700,24 @@ void addarn(const UDSPInstruction& opc)
g_dsp.r[dreg] += (s16)g_dsp.r[DSP_REG_IX0 + sreg];
}
// 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 TempProd = dsp_get_long_prod();
// update prod
u8 sreg = (opc.hex >> 12) & 0x1;
s64 Prod = (s64)dsp_get_acc_m(sreg) * (s64)dsp_get_acc_h(sreg) * GetMultiplyModifier();
u8 treg = (opc.hex >> 11) & 0x1;
s64 Prod = (s64)dsp_get_acc_m(sreg) * (s64)dsp_get_ax_h(treg) * GetMultiplyModifier();
dsp_set_long_prod(Prod);
// update acc
u8 rreg = (opc.hex >> 8) & 0x1;
s64 acc = TempProd + g_dsp.r[rreg];
s64 acc = TempProd + dsp_get_long_acc(rreg);
dsp_set_long_acc(rreg, acc);
Update_SR_Register64(acc);