static unsigned OptDecouple (CodeSeg* S)
/* Decouple operations, that is, do the following replacements:
**
** dex -> ldx #imm
** inx -> ldx #imm
** dey -> ldy #imm
** iny -> ldy #imm
** tax -> ldx #imm
** txa -> lda #imm
** tay -> ldy #imm
** tya -> lda #imm
** lda zp -> lda #imm
** ldx zp -> ldx #imm
** ldy zp -> ldy #imm
**
** Provided that the register values are known of course.
*/
{
unsigned Changes = 0;
unsigned I;
/* Walk over the entries */
I = 0;
while (I < CS_GetEntryCount (S)) {
const char* Arg;
/* Get next entry and it's input register values */
CodeEntry* E = CS_GetEntry (S, I);
const RegContents* In = &E->RI->In;
/* Assume we have no replacement */
CodeEntry* X = 0;
/* Check the instruction */
switch (E->OPC) {
case OP65_DEA:
if (RegValIsKnown (In->RegA)) {
Arg = MakeHexArg ((In->RegA - 1) & 0xFF);
X = NewCodeEntry (OP65_LDA, AM65_IMM, Arg, 0, E->LI);
}
break;
case OP65_DEX:
if (RegValIsKnown (In->RegX)) {
Arg = MakeHexArg ((In->RegX - 1) & 0xFF);
X = NewCodeEntry (OP65_LDX, AM65_IMM, Arg, 0, E->LI);
}
break;
case OP65_DEY:
if (RegValIsKnown (In->RegY)) {
Arg = MakeHexArg ((In->RegY - 1) & 0xFF);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
}
break;
case OP65_INA:
if (RegValIsKnown (In->RegA)) {
Arg = MakeHexArg ((In->RegA + 1) & 0xFF);
X = NewCodeEntry (OP65_LDA, AM65_IMM, Arg, 0, E->LI);
}
break;
case OP65_INX:
if (RegValIsKnown (In->RegX)) {
Arg = MakeHexArg ((In->RegX + 1) & 0xFF);
X = NewCodeEntry (OP65_LDX, AM65_IMM, Arg, 0, E->LI);
}
break;
case OP65_INY:
if (RegValIsKnown (In->RegY)) {
Arg = MakeHexArg ((In->RegY + 1) & 0xFF);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
}
break;
case OP65_LDA:
if (E->AM == AM65_ZP) {
switch (GetKnownReg (E->Use & REG_ZP, In)) {
case REG_TMP1:
Arg = MakeHexArg (In->Tmp1);
X = NewCodeEntry (OP65_LDA, AM65_IMM, Arg, 0, E->LI);
break;
case REG_PTR1_LO:
Arg = MakeHexArg (In->Ptr1Lo);
X = NewCodeEntry (OP65_LDA, AM65_IMM, Arg, 0, E->LI);
break;
case REG_PTR1_HI:
Arg = MakeHexArg (In->Ptr1Hi);
X = NewCodeEntry (OP65_LDA, AM65_IMM, Arg, 0, E->LI);
break;
case REG_SREG_LO:
Arg = MakeHexArg (In->SRegLo);
X = NewCodeEntry (OP65_LDA, AM65_IMM, Arg, 0, E->LI);
break;
case REG_SREG_HI:
Arg = MakeHexArg (In->SRegHi);
X = NewCodeEntry (OP65_LDA, AM65_IMM, Arg, 0, E->LI);
break;
}
}
break;
case OP65_LDX:
if (E->AM == AM65_ZP) {
switch (GetKnownReg (E->Use & REG_ZP, In)) {
case REG_TMP1:
Arg = MakeHexArg (In->Tmp1);
X = NewCodeEntry (OP65_LDX, AM65_IMM, Arg, 0, E->LI);
break;
case REG_PTR1_LO:
Arg = MakeHexArg (In->Ptr1Lo);
X = NewCodeEntry (OP65_LDX, AM65_IMM, Arg, 0, E->LI);
break;
case REG_PTR1_HI:
Arg = MakeHexArg (In->Ptr1Hi);
X = NewCodeEntry (OP65_LDX, AM65_IMM, Arg, 0, E->LI);
break;
case REG_SREG_LO:
Arg = MakeHexArg (In->SRegLo);
X = NewCodeEntry (OP65_LDX, AM65_IMM, Arg, 0, E->LI);
break;
case REG_SREG_HI:
Arg = MakeHexArg (In->SRegHi);
X = NewCodeEntry (OP65_LDX, AM65_IMM, Arg, 0, E->LI);
break;
}
}
break;
case OP65_LDY:
if (E->AM == AM65_ZP) {
switch (GetKnownReg (E->Use, In)) {
case REG_TMP1:
Arg = MakeHexArg (In->Tmp1);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
break;
case REG_PTR1_LO:
Arg = MakeHexArg (In->Ptr1Lo);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
break;
case REG_PTR1_HI:
Arg = MakeHexArg (In->Ptr1Hi);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
break;
case REG_SREG_LO:
Arg = MakeHexArg (In->SRegLo);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
break;
case REG_SREG_HI:
Arg = MakeHexArg (In->SRegHi);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
break;
}
}
break;
case OP65_TAX:
if (E->RI->In.RegA >= 0) {
Arg = MakeHexArg (In->RegA);
X = NewCodeEntry (OP65_LDX, AM65_IMM, Arg, 0, E->LI);
}
break;
case OP65_TAY:
if (E->RI->In.RegA >= 0) {
Arg = MakeHexArg (In->RegA);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, E->LI);
}
break;
case OP65_TXA:
if (E->RI->In.RegX >= 0) {
Arg = MakeHexArg (In->RegX);
X = NewCodeEntry (OP65_LDA, AM65_IMM, Arg, 0, E->LI);
}
break;
case OP65_TYA:
if (E->RI->In.RegY >= 0) {
Arg = MakeHexArg (In->RegY);
X = NewCodeEntry (OP65_LDA, AM65_IMM, Arg, 0, E->LI);
}
break;
default:
/* Avoid gcc warnings */
break;
}
/* Insert the replacement if we have one */
if (X) {
CS_InsertEntry (S, X, I+1);
CS_DelEntry (S, I);
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
void CE_GenRegInfo (CodeEntry* E, RegContents* InputRegs)
/* Generate register info for this instruction. If an old info exists, it is
** overwritten.
*/
{
/* Pointers to the register contents */
RegContents* In;
RegContents* Out;
/* Function register usage */
unsigned short Use, Chg;
/* If we don't have a register info struct, allocate one. */
if (E->RI == 0) {
E->RI = NewRegInfo (InputRegs);
} else {
if (InputRegs) {
E->RI->In = *InputRegs;
} else {
RC_Invalidate (&E->RI->In);
}
E->RI->Out2 = E->RI->Out = E->RI->In;
}
/* Get pointers to the register contents */
In = &E->RI->In;
Out = &E->RI->Out;
/* Handle the different instructions */
switch (E->OPC) {
case OP65_ADC:
/* We don't know the value of the carry, so the result is
** always unknown.
*/
Out->RegA = UNKNOWN_REGVAL;
break;
case OP65_AND:
if (RegValIsKnown (In->RegA)) {
if (CE_IsConstImm (E)) {
Out->RegA = In->RegA & (short) E->Num;
} else if (E->AM == AM65_ZP) {
switch (GetKnownReg (E->Use & REG_ZP, In)) {
case REG_TMP1:
Out->RegA = In->RegA & In->Tmp1;
break;
case REG_PTR1_LO:
Out->RegA = In->RegA & In->Ptr1Lo;
break;
case REG_PTR1_HI:
Out->RegA = In->RegA & In->Ptr1Hi;
break;
case REG_SREG_LO:
Out->RegA = In->RegA & In->SRegLo;
break;
case REG_SREG_HI:
Out->RegA = In->RegA & In->SRegHi;
break;
default:
Out->RegA = UNKNOWN_REGVAL;
break;
}
} else {
Out->RegA = UNKNOWN_REGVAL;
}
} else if (CE_IsKnownImm (E, 0)) {
/* A and $00 does always give zero */
Out->RegA = 0;
}
break;
case OP65_ASL:
if (E->AM == AM65_ACC && RegValIsKnown (In->RegA)) {
Out->RegA = (In->RegA << 1) & 0xFF;
} else if (E->AM == AM65_ZP) {
switch (GetKnownReg (E->Chg & REG_ZP, In)) {
case REG_TMP1:
Out->Tmp1 = (In->Tmp1 << 1) & 0xFF;
break;
case REG_PTR1_LO:
Out->Ptr1Lo = (In->Ptr1Lo << 1) & 0xFF;
break;
case REG_PTR1_HI:
Out->Ptr1Hi = (In->Ptr1Hi << 1) & 0xFF;
break;
case REG_SREG_LO:
Out->SRegLo = (In->SRegLo << 1) & 0xFF;
break;
case REG_SREG_HI:
Out->SRegHi = (In->SRegHi << 1) & 0xFF;
break;
}
} else if (E->AM == AM65_ZPX) {
/* Invalidates all ZP registers */
RC_InvalidateZP (Out);
}
break;
case OP65_BCC:
break;
case OP65_BCS:
break;
case OP65_BEQ:
break;
case OP65_BIT:
break;
case OP65_BMI:
break;
case OP65_BNE:
break;
case OP65_BPL:
break;
case OP65_BRA:
break;
case OP65_BRK:
break;
case OP65_BVC:
break;
case OP65_BVS:
break;
case OP65_CLC:
break;
case OP65_CLD:
break;
case OP65_CLI:
break;
case OP65_CLV:
break;
case OP65_CMP:
break;
case OP65_CPX:
break;
case OP65_CPY:
break;
case OP65_DEA:
if (RegValIsKnown (In->RegA)) {
Out->RegA = (In->RegA - 1) & 0xFF;
}
break;
case OP65_DEC:
if (E->AM == AM65_ACC && RegValIsKnown (In->RegA)) {
Out->RegA = (In->RegA - 1) & 0xFF;
} else if (E->AM == AM65_ZP) {
switch (GetKnownReg (E->Chg & REG_ZP, In)) {
case REG_TMP1:
Out->Tmp1 = (In->Tmp1 - 1) & 0xFF;
break;
case REG_PTR1_LO:
Out->Ptr1Lo = (In->Ptr1Lo - 1) & 0xFF;
break;
case REG_PTR1_HI:
Out->Ptr1Hi = (In->Ptr1Hi - 1) & 0xFF;
break;
case REG_SREG_LO:
Out->SRegLo = (In->SRegLo - 1) & 0xFF;
break;
case REG_SREG_HI:
Out->SRegHi = (In->SRegHi - 1) & 0xFF;
break;
}
} else if (E->AM == AM65_ZPX) {
/* Invalidates all ZP registers */
RC_InvalidateZP (Out);
}
break;
case OP65_DEX:
if (RegValIsKnown (In->RegX)) {
Out->RegX = (In->RegX - 1) & 0xFF;
}
break;
case OP65_DEY:
if (RegValIsKnown (In->RegY)) {
Out->RegY = (In->RegY - 1) & 0xFF;
}
break;
case OP65_EOR:
if (RegValIsKnown (In->RegA)) {
if (CE_IsConstImm (E)) {
Out->RegA = In->RegA ^ (short) E->Num;
} else if (E->AM == AM65_ZP) {
switch (GetKnownReg (E->Use & REG_ZP, In)) {
case REG_TMP1:
Out->RegA = In->RegA ^ In->Tmp1;
break;
case REG_PTR1_LO:
Out->RegA = In->RegA ^ In->Ptr1Lo;
break;
case REG_PTR1_HI:
Out->RegA = In->RegA ^ In->Ptr1Hi;
break;
case REG_SREG_LO:
Out->RegA = In->RegA ^ In->SRegLo;
break;
case REG_SREG_HI:
Out->RegA = In->RegA ^ In->SRegHi;
break;
default:
Out->RegA = UNKNOWN_REGVAL;
break;
}
} else {
Out->RegA = UNKNOWN_REGVAL;
}
}
break;
case OP65_INA:
if (RegValIsKnown (In->RegA)) {
Out->RegA = (In->RegA + 1) & 0xFF;
}
break;
case OP65_INC:
if (E->AM == AM65_ACC && RegValIsKnown (In->RegA)) {
Out->RegA = (In->RegA + 1) & 0xFF;
} else if (E->AM == AM65_ZP) {
switch (GetKnownReg (E->Chg & REG_ZP, In)) {
case REG_TMP1:
Out->Tmp1 = (In->Tmp1 + 1) & 0xFF;
break;
case REG_PTR1_LO:
Out->Ptr1Lo = (In->Ptr1Lo + 1) & 0xFF;
break;
case REG_PTR1_HI:
Out->Ptr1Hi = (In->Ptr1Hi + 1) & 0xFF;
break;
case REG_SREG_LO:
Out->SRegLo = (In->SRegLo + 1) & 0xFF;
break;
case REG_SREG_HI:
Out->SRegHi = (In->SRegHi + 1) & 0xFF;
break;
}
} else if (E->AM == AM65_ZPX) {
/* Invalidates all ZP registers */
RC_InvalidateZP (Out);
}
break;
case OP65_INX:
if (RegValIsKnown (In->RegX)) {
Out->RegX = (In->RegX + 1) & 0xFF;
}
break;
case OP65_INY:
if (RegValIsKnown (In->RegY)) {
Out->RegY = (In->RegY + 1) & 0xFF;
}
break;
case OP65_JCC:
break;
case OP65_JCS:
break;
case OP65_JEQ:
break;
case OP65_JMI:
break;
case OP65_JMP:
break;
case OP65_JNE:
break;
case OP65_JPL:
break;
case OP65_JSR:
/* Get the code info for the function */
GetFuncInfo (E->Arg, &Use, &Chg);
if (Chg & REG_A) {
Out->RegA = UNKNOWN_REGVAL;
}
if (Chg & REG_X) {
Out->RegX = UNKNOWN_REGVAL;
}
if (Chg & REG_Y) {
Out->RegY = UNKNOWN_REGVAL;
}
if (Chg & REG_TMP1) {
Out->Tmp1 = UNKNOWN_REGVAL;
}
if (Chg & REG_PTR1_LO) {
Out->Ptr1Lo = UNKNOWN_REGVAL;
}
if (Chg & REG_PTR1_HI) {
Out->Ptr1Hi = UNKNOWN_REGVAL;
}
if (Chg & REG_SREG_LO) {
Out->SRegLo = UNKNOWN_REGVAL;
}
if (Chg & REG_SREG_HI) {
Out->SRegHi = UNKNOWN_REGVAL;
}
/* ## FIXME: Quick hack for some known functions: */
if (strcmp (E->Arg, "complax") == 0) {
if (RegValIsKnown (In->RegA)) {
Out->RegA = (In->RegA ^ 0xFF);
}
if (RegValIsKnown (In->RegX)) {
Out->RegX = (In->RegX ^ 0xFF);
}
} else if (strcmp (E->Arg, "tosandax") == 0) {
if (In->RegA == 0) {
Out->RegA = 0;
}
if (In->RegX == 0) {
Out->RegX = 0;
}
} else if (strcmp (E->Arg, "tosaslax") == 0) {
if (RegValIsKnown (In->RegA) && (In->RegA & 0x0F) >= 8) {
printf ("Hey!\n");
Out->RegA = 0;
}
} else if (strcmp (E->Arg, "tosorax") == 0) {
if (In->RegA == 0xFF) {
Out->RegA = 0xFF;
}
if (In->RegX == 0xFF) {
Out->RegX = 0xFF;
}
} else if (strcmp (E->Arg, "tosshlax") == 0) {
if ((In->RegA & 0x0F) >= 8) {
Out->RegA = 0;
}
} else if (FindBoolCmpCond (E->Arg) != CMP_INV ||
FindTosCmpCond (E->Arg) != CMP_INV) {
/* Result is boolean value, so X is zero on output */
Out->RegX = 0;
}
break;
case OP65_JVC:
break;
case OP65_JVS:
break;
case OP65_LDA:
if (CE_IsConstImm (E)) {
Out->RegA = (unsigned char) E->Num;
} else if (E->AM == AM65_ZP) {
switch (GetKnownReg (E->Use & REG_ZP, In)) {
case REG_TMP1:
Out->RegA = In->Tmp1;
break;
case REG_PTR1_LO:
Out->RegA = In->Ptr1Lo;
break;
case REG_PTR1_HI:
Out->RegA = In->Ptr1Hi;
break;
case REG_SREG_LO:
Out->RegA = In->SRegLo;
break;
case REG_SREG_HI:
Out->RegA = In->SRegHi;
break;
default:
Out->RegA = UNKNOWN_REGVAL;
break;
}
} else {
/* A is now unknown */
Out->RegA = UNKNOWN_REGVAL;
}
break;
case OP65_LDX:
if (CE_IsConstImm (E)) {
Out->RegX = (unsigned char) E->Num;
} else if (E->AM == AM65_ZP) {
switch (GetKnownReg (E->Use & REG_ZP, In)) {
case REG_TMP1:
Out->RegX = In->Tmp1;
break;
case REG_PTR1_LO:
Out->RegX = In->Ptr1Lo;
break;
case REG_PTR1_HI:
Out->RegX = In->Ptr1Hi;
break;
case REG_SREG_LO:
Out->RegX = In->SRegLo;
break;
case REG_SREG_HI:
Out->RegX = In->SRegHi;
break;
default:
Out->RegX = UNKNOWN_REGVAL;
break;
}
} else {
/* X is now unknown */
Out->RegX = UNKNOWN_REGVAL;
}
break;
case OP65_LDY:
if (CE_IsConstImm (E)) {
Out->RegY = (unsigned char) E->Num;
} else if (E->AM == AM65_ZP) {
switch (GetKnownReg (E->Use & REG_ZP, In)) {
case REG_TMP1:
Out->RegY = In->Tmp1;
break;
case REG_PTR1_LO:
Out->RegY = In->Ptr1Lo;
break;
case REG_PTR1_HI:
Out->RegY = In->Ptr1Hi;
break;
case REG_SREG_LO:
Out->RegY = In->SRegLo;
break;
case REG_SREG_HI:
Out->RegY = In->SRegHi;
break;
default:
Out->RegY = UNKNOWN_REGVAL;
break;
}
} else {
/* Y is now unknown */
Out->RegY = UNKNOWN_REGVAL;
}
break;
case OP65_LSR:
if (E->AM == AM65_ACC && RegValIsKnown (In->RegA)) {
Out->RegA = (In->RegA >> 1) & 0xFF;
} else if (E->AM == AM65_ZP) {
