unsigned OptCmp1 (CodeSeg* S)
/* Search for the sequence
*
* ldx xx
* stx tmp1
* ora tmp1
*
* and replace it by
*
* ora xx
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[3];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_LDX &&
!CS_RangeHasLabel (S, I+1, 2) &&
CS_GetEntries (S, L+1, I+1, 2) &&
L[1]->OPC == OP65_STX &&
strcmp (L[1]->Arg, "tmp1") == 0 &&
L[2]->OPC == OP65_ORA &&
strcmp (L[2]->Arg, "tmp1") == 0) {
CodeEntry* X;
/* Insert the ora instead */
X = NewCodeEntry (OP65_ORA, L[0]->AM, L[0]->Arg, 0, L[0]->LI);
CS_InsertEntry (S, X, I);
/* Remove all other instructions */
CS_DelEntries (S, I+1, 3);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptStore4 (CodeSeg* S)
/* Search for the sequence
**
** sta xx
** stx yy
** lda xx
** ldx yy
**
** and remove the useless load, provided that the next insn doesn't use flags
** from the load.
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[5];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_STA &&
(L[0]->AM == AM65_ABS || L[0]->AM == AM65_ZP) &&
!CS_RangeHasLabel (S, I+1, 3) &&
CS_GetEntries (S, L+1, I+1, 4) &&
L[1]->OPC == OP65_STX &&
L[1]->AM == L[0]->AM &&
L[2]->OPC == OP65_LDA &&
L[2]->AM == L[0]->AM &&
L[3]->OPC == OP65_LDX &&
L[3]->AM == L[1]->AM &&
strcmp (L[0]->Arg, L[2]->Arg) == 0 &&
strcmp (L[1]->Arg, L[3]->Arg) == 0 &&
!CE_UseLoadFlags (L[4])) {
/* Register has already the correct value, remove the loads */
CS_DelEntries (S, I+2, 2);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptStore1 (CodeSeg* S)
/* Search for the sequence
**
** ldy #n
** jsr staxysp
** ldy #n+1
** jsr ldaxysp
**
** and remove the useless load.
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[4];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_LDY &&
CE_IsConstImm (L[0]) &&
L[0]->Num < 0xFF &&
!CS_RangeHasLabel (S, I+1, 3) &&
CS_GetEntries (S, L+1, I+1, 3) &&
CE_IsCallTo (L[1], "staxysp") &&
L[2]->OPC == OP65_LDY &&
CE_IsKnownImm (L[2], L[0]->Num + 1) &&
CE_IsCallTo (L[3], "ldaxysp")) {
/* Register has already the correct value, remove the loads */
CS_DelEntries (S, I+2, 2);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptStore5 (CodeSeg* S)
/* Search for the sequence
**
** lda foo
** ldx bar
** sta something
** stx something-else
**
** and replace it by
**
** lda foo
** sta something
** lda bar
** sta something-else
**
** if X is not used later. This replacement doesn't save any cycles or bytes,
** but it keeps the value of X, which may be reused later.
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[4];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_LDA &&
!CS_RangeHasLabel (S, I+1, 3) &&
CS_GetEntries (S, L+1, I+1, 3) &&
L[1]->OPC == OP65_LDX &&
L[2]->OPC == OP65_STA &&
L[3]->OPC == OP65_STX &&
!RegXUsed (S, I+4)) {
CodeEntry* X;
/* Insert the code after the sequence */
X = NewCodeEntry (OP65_LDA, L[1]->AM, L[1]->Arg, 0, L[1]->LI);
CS_InsertEntry (S, X, I+4);
X = NewCodeEntry (OP65_STA, L[3]->AM, L[3]->Arg, 0, L[3]->LI);
CS_InsertEntry (S, X, I+5);
/* Delete the old code */
CS_DelEntry (S, I+3);
CS_DelEntry (S, I+1);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptSub2 (CodeSeg* S)
/* Search for the sequence
**
** lda xx
** sec
** sta tmp1
** lda yy
** sbc tmp1
** sta yy
**
** and replace it by
**
** sec
** lda yy
** sbc xx
** sta yy
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[5];
/* Get next entry */
CodeEntry* E = CS_GetEntry (S, I);
/* Check for the sequence */
if (E->OPC == OP65_LDA &&
!CS_RangeHasLabel (S, I+1, 5) &&
CS_GetEntries (S, L, I+1, 5) &&
L[0]->OPC == OP65_SEC &&
L[1]->OPC == OP65_STA &&
strcmp (L[1]->Arg, "tmp1") == 0 &&
L[2]->OPC == OP65_LDA &&
L[3]->OPC == OP65_SBC &&
strcmp (L[3]->Arg, "tmp1") == 0 &&
L[4]->OPC == OP65_STA &&
strcmp (L[4]->Arg, L[2]->Arg) == 0) {
/* Remove the store to tmp1 */
CS_DelEntry (S, I+2);
/* Remove the subtraction */
CS_DelEntry (S, I+3);
/* Move the lda to the position of the subtraction and change the
** op to SBC.
*/
CS_MoveEntry (S, I, I+3);
CE_ReplaceOPC (E, OP65_SBC);
/* If the sequence head had a label, move this label back to the
** head.
*/
if (CE_HasLabel (E)) {
CS_MoveLabels (S, E, L[0]);
}
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned Opt65C02BitOps (CodeSeg* S)
/* Use special bit op instructions of the C02 */
{
unsigned Changes = 0;
unsigned I;
/* Generate register info for this step */
CS_GenRegInfo (S);
/* Walk over the entries */
I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[3];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_LDA &&
(L[0]->AM == AM65_ZP || L[0]->AM == AM65_ABS) &&
!CS_RangeHasLabel (S, I+1, 2) &&
CS_GetEntries (S, L+1, I+1, 2) &&
(L[1]->OPC == OP65_AND || L[1]->OPC == OP65_ORA) &&
CE_IsConstImm (L[1]) &&
L[2]->OPC == OP65_STA &&
L[2]->AM == L[0]->AM &&
strcmp (L[2]->Arg, L[0]->Arg) == 0 &&
!RegAUsed (S, I+3)) {
char Buf[32];
CodeEntry* X;
/* Use TRB for AND and TSB for ORA */
if (L[1]->OPC == OP65_AND) {
/* LDA #XX */
sprintf (Buf, "$%02X", (int) ((~L[1]->Num) & 0xFF));
X = NewCodeEntry (OP65_LDA, AM65_IMM, Buf, 0, L[1]->LI);
CS_InsertEntry (S, X, I+3);
/* TRB */
X = NewCodeEntry (OP65_TRB, L[0]->AM, L[0]->Arg, 0, L[0]->LI);
CS_InsertEntry (S, X, I+4);
} else {
/* LDA #XX */
sprintf (Buf, "$%02X", (int) L[1]->Num);
X = NewCodeEntry (OP65_LDA, AM65_IMM, Buf, 0, L[1]->LI);
CS_InsertEntry (S, X, I+3);
/* TSB */
X = NewCodeEntry (OP65_TSB, L[0]->AM, L[0]->Arg, 0, L[0]->LI);
CS_InsertEntry (S, X, I+4);
}
/* Delete the old stuff */
CS_DelEntries (S, I, 3);
/* We had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Free register info */
CS_FreeRegInfo (S);
/* Return the number of changes made */
return Changes;
}
static unsigned OptLoad2 (CodeSeg* S)
/* Replace calls to ldaxysp by inline code */
{
unsigned I;
unsigned Changes = 0;
/* Walk over the entries */
I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[3];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (CE_IsCallTo (L[0], "ldaxysp")) {
CodeEntry* X;
/* Followed by sta abs/stx abs? */
if (CS_GetEntries (S, L+1, I+1, 2) &&
L[1]->OPC == OP65_STA &&
L[2]->OPC == OP65_STX &&
(L[1]->Arg == 0 ||
L[2]->Arg == 0 ||
strcmp (L[1]->Arg, L[2]->Arg) != 0) &&
!CS_RangeHasLabel (S, I+1, 2) &&
!RegXUsed (S, I+3)) {
/* A/X are stored into memory somewhere and X is not used
** later
*/
/* lda (sp),y */
X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "sp", 0, L[0]->LI);
CS_InsertEntry (S, X, I+3);
/* sta abs */
X = NewCodeEntry (OP65_STA, L[2]->AM, L[2]->Arg, 0, L[2]->LI);
CS_InsertEntry (S, X, I+4);
/* dey */
X = NewCodeEntry (OP65_DEY, AM65_IMP, 0, 0, L[0]->LI);
CS_InsertEntry (S, X, I+5);
/* lda (sp),y */
X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "sp", 0, L[0]->LI);
CS_InsertEntry (S, X, I+6);
/* sta abs */
X = NewCodeEntry (OP65_STA, L[1]->AM, L[1]->Arg, 0, L[1]->LI);
CS_InsertEntry (S, X, I+7);
/* Now remove the call to the subroutine and the sta/stx */
CS_DelEntries (S, I, 3);
} else {
/* Standard replacement */
/* lda (sp),y */
X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "sp", 0, L[0]->LI);
CS_InsertEntry (S, X, I+1);
/* tax */
X = NewCodeEntry (OP65_TAX, AM65_IMP, 0, 0, L[0]->LI);
CS_InsertEntry (S, X, I+2);
/* dey */
X = NewCodeEntry (OP65_DEY, AM65_IMP, 0, 0, L[0]->LI);
CS_InsertEntry (S, X, I+3);
/* lda (sp),y */
X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "sp", 0, L[0]->LI);
CS_InsertEntry (S, X, I+4);
/* Now remove the call to the subroutine */
CS_DelEntry (S, I);
}
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptCmp3 (CodeSeg* S)
/* Search for
*
* lda/and/ora/eor ...
* cmp #$00
* jeq/jne
* or
* lda/and/ora/eor ...
* cmp #$00
* jsr boolxx
*
* and remove the cmp.
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[3];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if ((L[0]->OPC == OP65_ADC ||
L[0]->OPC == OP65_AND ||
L[0]->OPC == OP65_ASL ||
L[0]->OPC == OP65_DEA ||
L[0]->OPC == OP65_EOR ||
L[0]->OPC == OP65_INA ||
L[0]->OPC == OP65_LDA ||
L[0]->OPC == OP65_LSR ||
L[0]->OPC == OP65_ORA ||
L[0]->OPC == OP65_PLA ||
L[0]->OPC == OP65_SBC ||
L[0]->OPC == OP65_TXA ||
L[0]->OPC == OP65_TYA) &&
!CS_RangeHasLabel (S, I+1, 2) &&
CS_GetEntries (S, L+1, I+1, 2) &&
L[1]->OPC == OP65_CMP &&
CE_IsKnownImm (L[1], 0)) {
int Delete = 0;
/* Check for the call to boolxx. We only remove the compare if
* the carry flag is not evaluated later, because the load will
* not set the carry flag.
*/
if (L[2]->OPC == OP65_JSR) {
switch (FindBoolCmpCond (L[2]->Arg)) {
case CMP_EQ:
case CMP_NE:
case CMP_GT:
case CMP_GE:
case CMP_LT:
case CMP_LE:
/* Remove the compare */
Delete = 1;
break;
case CMP_UGT:
case CMP_UGE:
case CMP_ULT:
case CMP_ULE:
case CMP_INV:
/* Leave it alone */
break;
}
} else if ((L[2]->Info & OF_FBRA) != 0) {
/* The following insn branches on the condition of the load,
* so the compare instruction might be removed. For safety,
* do some more checks if the carry isn't used later, since
* the compare does set the carry, but the load does not.
*/
CodeEntry* E;
CodeEntry* N;
if ((E = CS_GetNextEntry (S, I+2)) != 0 &&
L[2]->JumpTo != 0 &&
(N = L[2]->JumpTo->Owner) != 0 &&
N->OPC != OP65_BCC &&
N->OPC != OP65_BCS &&
N->OPC != OP65_JCC &&
N->OPC != OP65_JCS &&
(N->OPC != OP65_JSR ||
FindBoolCmpCond (N->Arg) == CMP_INV)) {
/* The following insn branches on the condition of a load,
* and there's no use of the carry flag in sight, so the
* compare instruction can be removed.
*/
Delete = 1;
}
}
/* Delete the compare if we can */
if (Delete) {
CS_DelEntry (S, I+1);
++Changes;
}
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptShift5 (CodeSeg* S)
/* Search for the sequence
*
* lda xxx
* ldx yyy
* jsr aslax1/asrax1/shlax1/shrax1
* sta aaa
* stx bbb
*
* and replace it by
*
* lda xxx
* asl a
* sta aaa
* lda yyy
* rol a
* sta bbb
*
* or similar, provided that a/x is not used later
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
unsigned ShiftType;
CodeEntry* L[5];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_LDA &&
(L[0]->AM == AM65_ABS || L[0]->AM == AM65_ZP) &&
CS_GetEntries (S, L+1, I+1, 4) &&
!CS_RangeHasLabel (S, I+1, 4) &&
L[1]->OPC == OP65_LDX &&
(L[1]->AM == AM65_ABS || L[1]->AM == AM65_ZP) &&
L[2]->OPC == OP65_JSR &&
(ShiftType = GetShift (L[2]->Arg)) != SHIFT_NONE &&
SHIFT_COUNT(ShiftType) == 1 &&
L[3]->OPC == OP65_STA &&
(L[3]->AM == AM65_ABS || L[3]->AM == AM65_ZP) &&
L[4]->OPC == OP65_STX &&
(L[4]->AM == AM65_ABS || L[4]->AM == AM65_ZP) &&
!RegAXUsed (S, I+5)) {
CodeEntry* X;
/* Handle the four shift types differently */
switch (ShiftType) {
case SHIFT_ASR_1:
X = NewCodeEntry (OP65_LDA, L[1]->AM, L[1]->Arg, 0, L[1]->LI);
CS_InsertEntry (S, X, I+5);
X = NewCodeEntry (OP65_CMP, AM65_IMM, "$80", 0, L[2]->LI);
CS_InsertEntry (S, X, I+6);
X = NewCodeEntry (OP65_ROR, AM65_ACC, "a", 0, L[2]->LI);
CS_InsertEntry (S, X, I+7);
X = NewCodeEntry (OP65_STA, L[4]->AM, L[4]->Arg, 0, L[4]->LI);
CS_InsertEntry (S, X, I+8);
X = NewCodeEntry (OP65_LDA, L[0]->AM, L[0]->Arg, 0, L[0]->LI);
CS_InsertEntry (S, X, I+9);
X = NewCodeEntry (OP65_ROR, AM65_ACC, "a", 0, L[2]->LI);
CS_InsertEntry (S, X, I+10);
X = NewCodeEntry (OP65_STA, L[3]->AM, L[3]->Arg, 0, L[3]->LI);
CS_InsertEntry (S, X, I+11);
CS_DelEntries (S, I, 5);
break;
case SHIFT_LSR_1:
X = NewCodeEntry (OP65_LDA, L[1]->AM, L[1]->Arg, 0, L[1]->LI);
CS_InsertEntry (S, X, I+5);
X = NewCodeEntry (OP65_LSR, AM65_ACC, "a", 0, L[2]->LI);
CS_InsertEntry (S, X, I+6);
X = NewCodeEntry (OP65_STA, L[4]->AM, L[4]->Arg, 0, L[4]->LI);
CS_InsertEntry (S, X, I+7);
X = NewCodeEntry (OP65_LDA, L[0]->AM, L[0]->Arg, 0, L[0]->LI);
CS_InsertEntry (S, X, I+8);
X = NewCodeEntry (OP65_ROR, AM65_ACC, "a", 0, L[2]->LI);
CS_InsertEntry (S, X, I+9);
X = NewCodeEntry (OP65_STA, L[3]->AM, L[3]->Arg, 0, L[3]->LI);
CS_InsertEntry (S, X, I+10);
CS_DelEntries (S, I, 5);
break;
case SHIFT_LSL_1:
case SHIFT_ASL_1:
/* These two are identical */
X = NewCodeEntry (OP65_ASL, AM65_ACC, "a", 0, L[2]->LI);
CS_InsertEntry (S, X, I+1);
X = NewCodeEntry (OP65_STA, L[3]->AM, L[3]->Arg, 0, L[3]->LI);
CS_InsertEntry (S, X, I+2);
X = NewCodeEntry (OP65_LDA, L[1]->AM, L[1]->Arg, 0, L[1]->LI);
CS_InsertEntry (S, X, I+3);
X = NewCodeEntry (OP65_ROL, AM65_ACC, "a", 0, L[2]->LI);
CS_InsertEntry (S, X, I+4);
X = NewCodeEntry (OP65_STA, L[4]->AM, L[4]->Arg, 0, L[4]->LI);
CS_InsertEntry (S, X, I+5);
CS_DelEntries (S, I+6, 4);
break;
}
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptBNegAX2 (CodeSeg* S)
/* Search for the sequence:
*
* ldy #xx
* jsr ldaxysp
* jsr bnegax
* jne/jeq ...
*
* and replace it by
*
* ldy #xx
* lda (sp),y
* dey
* ora (sp),y
* jeq/jne ...
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[4];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_LDY &&
CE_IsConstImm (L[0]) &&
!CS_RangeHasLabel (S, I+1, 3) &&
CS_GetEntries (S, L+1, I+1, 3) &&
CE_IsCallTo (L[1], "ldaxysp") &&
CE_IsCallTo (L[2], "bnegax") &&
(L[3]->Info & OF_ZBRA) != 0) {
CodeEntry* X;
/* lda (sp),y */
X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "sp", 0, L[1]->LI);
CS_InsertEntry (S, X, I+1);
/* dey */
X = NewCodeEntry (OP65_DEY, AM65_IMP, 0, 0, L[1]->LI);
CS_InsertEntry (S, X, I+2);
/* ora (sp),y */
X = NewCodeEntry (OP65_ORA, AM65_ZP_INDY, "sp", 0, L[1]->LI);
CS_InsertEntry (S, X, I+3);
/* Invert the branch */
CE_ReplaceOPC (L[3], GetInverseBranch (L[3]->OPC));
/* Delete the entries no longer needed. */
CS_DelEntries (S, I+4, 2);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptShift3 (CodeSeg* S)
/* The sequence
*
* bcc L
* inx
* L: jsr shrax1
*
* may get replaced by
*
* ror a
*
* if X is zero on entry. For shift counts > 1, more
*
* shr a
*
* must be added.
*/
{
unsigned Changes = 0;
unsigned I;
/* Walk over the entries */
I = 0;
while (I < CS_GetEntryCount (S)) {
unsigned Shift;
unsigned Count;
CodeEntry* L[3];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if ((L[0]->OPC == OP65_BCC || L[0]->OPC == OP65_JCC) &&
L[0]->JumpTo != 0 &&
L[0]->RI->In.RegX == 0 &&
CS_GetEntries (S, L+1, I+1, 2) &&
L[1]->OPC == OP65_INX &&
L[0]->JumpTo->Owner == L[2] &&
!CS_RangeHasLabel (S, I, 2) &&
L[2]->OPC == OP65_JSR &&
(Shift = GetShift (L[2]->Arg)) != SHIFT_NONE &&
SHIFT_DIR (Shift) == SHIFT_DIR_RIGHT &&
(Count = SHIFT_COUNT (Shift)) > 0) {
/* Add the replacement insn instead */
CodeEntry* X = NewCodeEntry (OP65_ROR, AM65_ACC, "a", 0, L[2]->LI);
CS_InsertEntry (S, X, I+3);
while (--Count) {
X = NewCodeEntry (OP65_LSR, AM65_ACC, "a", 0, L[2]->LI);
CS_InsertEntry (S, X, I+4);
}
/* Remove the bcs/dex/jsr */
CS_DelEntries (S, I, 3);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptAdd1 (CodeSeg* S)
/* Search for the sequence
*
* ldy #xx
* jsr ldaxysp
* jsr pushax
* ldy #yy
* jsr ldaxysp
* jsr tosaddax
*
* and replace it by:
*
* ldy #xx-1
* lda (sp),y
* ldy #yy-3
* clc
* adc (sp),y
* pha
* ldy #xx
* lda (sp),y
* ldy #yy-2
* adc (sp),y
* tax
* pla
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[6];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_LDY &&
CE_IsConstImm (L[0]) &&
!CS_RangeHasLabel (S, I+1, 5) &&
CS_GetEntries (S, L+1, I+1, 5) &&
CE_IsCallTo (L[1], "ldaxysp") &&
CE_IsCallTo (L[2], "pushax") &&
L[3]->OPC == OP65_LDY &&
CE_IsConstImm (L[3]) &&
CE_IsCallTo (L[4], "ldaxysp") &&
CE_IsCallTo (L[5], "tosaddax")) {
CodeEntry* X;
const char* Arg;
/* Correct the stack of the first Y register load */
CE_SetNumArg (L[0], L[0]->Num - 1);
/* lda (sp),y */
X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "sp", 0, L[1]->LI);
CS_InsertEntry (S, X, I+1);
/* ldy #yy-3 */
Arg = MakeHexArg (L[3]->Num - 3);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, L[4]->LI);
CS_InsertEntry (S, X, I+2);
/* clc */
X = NewCodeEntry (OP65_CLC, AM65_IMP, 0, 0, L[5]->LI);
CS_InsertEntry (S, X, I+3);
/* adc (sp),y */
X = NewCodeEntry (OP65_ADC, AM65_ZP_INDY, "sp", 0, L[5]->LI);
CS_InsertEntry (S, X, I+4);
/* pha */
X = NewCodeEntry (OP65_PHA, AM65_IMP, 0, 0, L[5]->LI);
CS_InsertEntry (S, X, I+5);
/* ldy #xx (beware: L[0] has changed) */
Arg = MakeHexArg (L[0]->Num + 1);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, L[1]->LI);
CS_InsertEntry (S, X, I+6);
/* lda (sp),y */
X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "sp", 0, L[1]->LI);
CS_InsertEntry (S, X, I+7);
/* ldy #yy-2 */
Arg = MakeHexArg (L[3]->Num - 2);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, L[4]->LI);
CS_InsertEntry (S, X, I+8);
/* adc (sp),y */
X = NewCodeEntry (OP65_ADC, AM65_ZP_INDY, "sp", 0, L[5]->LI);
CS_InsertEntry (S, X, I+9);
/* tax */
X = NewCodeEntry (OP65_TAX, AM65_IMP, 0, 0, L[5]->LI);
CS_InsertEntry (S, X, I+10);
/* pla */
X = NewCodeEntry (OP65_PLA, AM65_IMP, 0, 0, L[5]->LI);
CS_InsertEntry (S, X, I+11);
/* Delete the old code */
CS_DelEntries (S, I+12, 5);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptAdd4 (CodeSeg* S)
/* Search for the sequence
*
* jsr pushax
* lda xxx
* ldx yyy
* jsr tosaddax
*
* and replace it by
*
* clc
* adc xxx
* pha
* txa
* adc yyy
* tax
* pla
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[4];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (CE_IsCallTo (L[0], "pushax") &&
CS_GetEntries (S, L+1, I+1, 3) &&
!CS_RangeHasLabel (S, I+1, 3) &&
L[1]->OPC == OP65_LDA &&
(L[1]->AM == AM65_ABS || L[1]->AM == AM65_ZP) &&
L[2]->OPC == OP65_LDX &&
(L[2]->AM == AM65_ABS || L[2]->AM == AM65_ZP) &&
CE_IsCallTo (L[3], "tosaddax")) {
CodeEntry* X;
/* Insert new code behind the sequence */
X = NewCodeEntry (OP65_CLC, AM65_IMP, 0, 0, L[3]->LI);
CS_InsertEntry (S, X, I+4);
/* adc xxx */
X = NewCodeEntry (OP65_ADC, L[1]->AM, L[1]->Arg, 0, L[3]->LI);
CS_InsertEntry (S, X, I+5);
/* pha */
X = NewCodeEntry (OP65_PHA, AM65_IMP, 0, 0, L[3]->LI);
CS_InsertEntry (S, X, I+6);
/* txa */
X = NewCodeEntry (OP65_TXA, AM65_IMP, 0, 0, L[3]->LI);
CS_InsertEntry (S, X, I+7);
/* adc yyy */
X = NewCodeEntry (OP65_ADC, L[2]->AM, L[2]->Arg, 0, L[3]->LI);
CS_InsertEntry (S, X, I+8);
/* tax */
X = NewCodeEntry (OP65_TAX, AM65_IMP, 0, 0, L[3]->LI);
CS_InsertEntry (S, X, I+9);
/* pla */
X = NewCodeEntry (OP65_PLA, AM65_IMP, 0, 0, L[3]->LI);
CS_InsertEntry (S, X, I+10);
/* Delete the old code */
CS_DelEntries (S, I, 4);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptAdd3 (CodeSeg* S)
/* Search for the sequence
*
* jsr pushax
* ldx #$00
* lda xxx
* jsr tosaddax
*
* and replace it by
*
* clc
* adc xxx
* bcc L1
* inx
* L1:
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[5];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (CE_IsCallTo (L[0], "pushax") &&
CS_GetEntries (S, L+1, I+1, 4) &&
!CS_RangeHasLabel (S, I+1, 3) &&
L[1]->OPC == OP65_LDX &&
CE_IsKnownImm (L[1], 0) &&
L[2]->OPC == OP65_LDA &&
CE_IsCallTo (L[3], "tosaddax")) {
CodeEntry* X;
CodeLabel* Label;
/* Insert new code behind the sequence */
X = NewCodeEntry (OP65_CLC, AM65_IMP, 0, 0, L[3]->LI);
CS_InsertEntry (S, X, I+4);
/* adc xxx */
X = NewCodeEntry (OP65_ADC, L[2]->AM, L[2]->Arg, 0, L[3]->LI);
CS_InsertEntry (S, X, I+5);
/* bcc L1 */
Label = CS_GenLabel (S, L[4]);
X = NewCodeEntry (OP65_BCC, AM65_BRA, Label->Name, Label, L[3]->LI);
CS_InsertEntry (S, X, I+6);
/* inx */
X = NewCodeEntry (OP65_INX, AM65_IMP, 0, 0, L[3]->LI);
CS_InsertEntry (S, X, I+7);
/* Delete the old code */
CS_DelEntries (S, I, 4);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptAdd2 (CodeSeg* S)
/* Search for the sequence
*
* ldy #xx
* jsr ldaxysp
* ldy #yy
* jsr addeqysp
*
* and replace it by:
*
* ldy #xx-1
* lda (sp),y
* ldy #yy
* clc
* adc (sp),y
* sta (sp),y
* ldy #xx
* lda (sp),y
* ldy #yy+1
* adc (sp),y
* sta (sp),y
*
* provided that a/x is not used later.
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[4];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_LDY &&
CE_IsConstImm (L[0]) &&
!CS_RangeHasLabel (S, I+1, 3) &&
CS_GetEntries (S, L+1, I+1, 3) &&
CE_IsCallTo (L[1], "ldaxysp") &&
L[2]->OPC == OP65_LDY &&
CE_IsConstImm (L[2]) &&
CE_IsCallTo (L[3], "addeqysp") &&
(GetRegInfo (S, I+4, REG_AX) & REG_AX) == 0) {
/* Insert new code behind the addeqysp */
const char* Arg;
CodeEntry* X;
/* ldy #xx-1 */
Arg = MakeHexArg (L[0]->Num-1);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, L[0]->LI);
CS_InsertEntry (S, X, I+4);
/* lda (sp),y */
X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "sp", 0, L[1]->LI);
CS_InsertEntry (S, X, I+5);
/* ldy #yy */
X = NewCodeEntry (OP65_LDY, AM65_IMM, L[2]->Arg, 0, L[2]->LI);
CS_InsertEntry (S, X, I+6);
/* clc */
X = NewCodeEntry (OP65_CLC, AM65_IMP, 0, 0, L[3]->LI);
CS_InsertEntry (S, X, I+7);
/* adc (sp),y */
X = NewCodeEntry (OP65_ADC, AM65_ZP_INDY, "sp", 0, L[3]->LI);
CS_InsertEntry (S, X, I+8);
/* sta (sp),y */
X = NewCodeEntry (OP65_STA, AM65_ZP_INDY, "sp", 0, L[3]->LI);
CS_InsertEntry (S, X, I+9);
/* ldy #xx */
X = NewCodeEntry (OP65_LDY, AM65_IMM, L[0]->Arg, 0, L[0]->LI);
CS_InsertEntry (S, X, I+10);
/* lda (sp),y */
X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "sp", 0, L[1]->LI);
CS_InsertEntry (S, X, I+11);
/* ldy #yy+1 */
Arg = MakeHexArg (L[2]->Num+1);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, L[2]->LI);
CS_InsertEntry (S, X, I+12);
/* adc (sp),y */
X = NewCodeEntry (OP65_ADC, AM65_ZP_INDY, "sp", 0, L[3]->LI);
CS_InsertEntry (S, X, I+13);
/* sta (sp),y */
X = NewCodeEntry (OP65_STA, AM65_ZP_INDY, "sp", 0, L[3]->LI);
CS_InsertEntry (S, X, I+14);
/* Delete the old code */
CS_DelEntries (S, I, 4);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
