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More optimizations

git-svn-id: svn://svn.cc65.org/cc65/trunk@839 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
cuz 2001-08-05 21:19:50 +00:00
parent 24403e151e
commit 0529c2044a

View File

@ -1839,6 +1839,198 @@ static unsigned OptPtrLoad1 (CodeSeg* S)
static unsigned OptPtrLoad2 (CodeSeg* S)
/* Search for the sequence:
*
* adc xxx
* tay
* txa
* adc yyy
* tax
* tya
* ldy
* jsr ldauidx
*
* and replace it by:
*
* adc xxx
* sta ptr1
* txa
* adc yyy
* sta ptr1+1
* ldy
* ldx #$00
* lda (ptr1),y
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[8];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_ADC &&
CS_GetEntries (S, L+1, I+1, 7) &&
L[1]->OPC == OP65_TAY &&
!CE_HasLabel (L[1]) &&
L[2]->OPC == OP65_TXA &&
!CE_HasLabel (L[2]) &&
L[3]->OPC == OP65_ADC &&
!CE_HasLabel (L[3]) &&
L[4]->OPC == OP65_TAX &&
!CE_HasLabel (L[4]) &&
L[5]->OPC == OP65_TYA &&
!CE_HasLabel (L[5]) &&
L[6]->OPC == OP65_LDY &&
!CE_HasLabel (L[6]) &&
L[7]->OPC == OP65_JSR &&
strcmp (L[7]->Arg, "ldauidx") == 0 &&
!CE_HasLabel (L[7])) {
CodeEntry* X;
/* Store the low byte and remove the TAY instead */
X = NewCodeEntry (OP65_STA, AM65_ZP, "ptr1", 0, L[0]->LI);
CS_InsertEntry (S, X, I+1);
CS_DelEntry (S, I+2);
/* Store the high byte */
X = NewCodeEntry (OP65_STA, AM65_ZP, "ptr1+1", 0, L[3]->LI);
CS_InsertEntry (S, X, I+4);
/* Delete more transfer insns */
CS_DelEntry (S, I+6);
CS_DelEntry (S, I+5);
/* Delete the call to ldauidx */
CS_DelEntry (S, I+6);
/* Load high and low byte */
X = NewCodeEntry (OP65_LDX, AM65_IMM, "$00", 0, L[6]->LI);
CS_InsertEntry (S, X, I+6);
X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "ptr1", 0, L[6]->LI);
CS_InsertEntry (S, X, I+7);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
static unsigned OptPtrLoad3 (CodeSeg* S)
/* Search for the sequence:
*
* adc xxx
* pha
* txa
* iny
* adc yyy
* tax
* pla
* ldy
* jsr ldauidx
*
* and replace it by:
*
* adc xxx
* sta ptr1
* txa
* iny
* adc yyy
* sta ptr1+1
* ldy
* ldx #$00
* lda (ptr1),y
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[9];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_ADC &&
CS_GetEntries (S, L+1, I+1, 8) &&
L[1]->OPC == OP65_PHA &&
!CE_HasLabel (L[1]) &&
L[2]->OPC == OP65_TXA &&
!CE_HasLabel (L[2]) &&
L[3]->OPC == OP65_INY &&
!CE_HasLabel (L[3]) &&
L[4]->OPC == OP65_ADC &&
!CE_HasLabel (L[4]) &&
L[5]->OPC == OP65_TAX &&
!CE_HasLabel (L[5]) &&
L[6]->OPC == OP65_PLA &&
!CE_HasLabel (L[6]) &&
L[7]->OPC == OP65_LDY &&
!CE_HasLabel (L[7]) &&
L[8]->OPC == OP65_JSR &&
strcmp (L[8]->Arg, "ldauidx") == 0 &&
!CE_HasLabel (L[8])) {
CodeEntry* X;
/* Store the low byte and remove the PHA instead */
X = NewCodeEntry (OP65_STA, AM65_ZP, "ptr1", 0, L[0]->LI);
CS_InsertEntry (S, X, I+1);
CS_DelEntry (S, I+2);
/* Store the high byte */
X = NewCodeEntry (OP65_STA, AM65_ZP, "ptr1+1", 0, L[4]->LI);
CS_InsertEntry (S, X, I+5);
/* Delete more transfer and PLA insns */
CS_DelEntry (S, I+7);
CS_DelEntry (S, I+6);
/* Delete the call to ldauidx */
CS_DelEntry (S, I+7);
/* Load high and low byte */
X = NewCodeEntry (OP65_LDX, AM65_IMM, "$00", 0, L[6]->LI);
CS_InsertEntry (S, X, I+7);
X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "ptr1", 0, L[6]->LI);
CS_InsertEntry (S, X, I+8);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
static unsigned OptPtrLoad4 (CodeSeg* S)
/* Search for the sequence
*
* ldy ...
@ -1941,8 +2133,10 @@ static OptFunc OptFuncs [] = {
OptEntry (OptPtrStore1, optPre),
OptEntry (OptPtrStore2, optPre),
/* Optimize loads through pointers */
OptEntry (OptPtrLoad1, optMain),
OptEntry (OptPtrLoad2, optMain),
OptEntry (OptPtrLoad1, optPre),
OptEntry (OptPtrLoad2, optPre),
OptEntry (OptPtrLoad3, optPre),
OptEntry (OptPtrLoad4, optMain),
/* Optimize calls to nega */
OptEntry (OptNegA1, optMain),
OptEntry (OptNegA2, optMain),