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Added a peephole optimization step for global array accesses

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git-svn-id: svn://svn.cc65.org/cc65/trunk@957 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
cuz 2001-09-20 19:47:32 +00:00
parent 03273a03f8
commit d694b9e88a
1 changed files with 216 additions and 3 deletions
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219
src/cc65/codeopt.c
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@ -1,4 +1,3 @@
/*****************************************************************************/
/* */
/* codeopt.c */
@ -40,6 +39,7 @@
#include "abend.h"
#include "chartype.h"
#include "print.h"
#include "xmalloc.h"
#include "xsprintf.h"
/* cc65 */
@ -2220,6 +2220,217 @@ static unsigned OptPtrLoad3 (CodeSeg* S)
static unsigned OptPtrLoad4 (CodeSeg* S)
/* Search for the sequence:
*
* lda #<(label+0)
* ldx #>(label+0)
* clc
* adc xxx
* bcc L
* inx
* L: ldy #$00
* jsr ldauidx
*
* and replace it by:
*
* ldy xxx
* ldx #$00
* lda label,y
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[8];
unsigned Len;
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_LDA &&
L[0]->AM == AM65_IMM &&
CS_GetEntries (S, L+1, I+1, 7) &&
L[1]->OPC == OP65_LDX &&
L[1]->AM == AM65_IMM &&
!CE_HasLabel (L[1]) &&
L[2]->OPC == OP65_CLC &&
!CE_HasLabel (L[2]) &&
L[3]->OPC == OP65_ADC &&
(L[3]->AM == AM65_ABS || L[3]->AM == AM65_ZP) &&
!CE_HasLabel (L[3]) &&
(L[4]->OPC == OP65_BCC || L[4]->OPC == OP65_JCC) &&
L[4]->JumpTo != 0 &&
L[4]->JumpTo->Owner == L[6] &&
!CE_HasLabel (L[4]) &&
L[5]->OPC == OP65_INX &&
!CE_HasLabel (L[5]) &&
L[6]->OPC == OP65_LDY &&
CE_KnownImm (L[6]) &&
L[6]->Num == 0 &&
L[7]->OPC == OP65_JSR &&
strcmp (L[7]->Arg, "ldauidx") == 0 &&
!CE_HasLabel (L[7]) &&
/* Check the label last because this is quite costly */
(Len = strlen (L[0]->Arg)) > 3 &&
L[0]->Arg[0] == '<' &&
L[0]->Arg[1] == '(' &&
strlen (L[1]->Arg) == Len &&
L[1]->Arg[0] == '>' &&
memcmp (L[0]->Arg+1, L[1]->Arg+1, Len-1) == 0) {
CodeEntry* X;
char* Label;
/* We will create all the new stuff behind the current one so
* we keep the line references.
*/
X = NewCodeEntry (OP65_LDY, L[3]->AM, L[3]->Arg, 0, L[0]->LI);
CS_InsertEntry (S, X, I+8);
X = NewCodeEntry (OP65_LDX, AM65_IMM, "$00", 0, L[0]->LI);
CS_InsertEntry (S, X, I+9);
Label = memcpy (xmalloc (Len-2), L[0]->Arg+2, Len-3);
Label[Len-3] = '\0';
X = NewCodeEntry (OP65_LDA, AM65_ABSY, Label, 0, L[0]->LI);
CS_InsertEntry (S, X, I+10);
xfree (Label);
/* Remove the old code */
CS_DelEntries (S, I, 8);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
static unsigned OptPtrLoad5 (CodeSeg* S)
/* Search for the sequence:
*
* lda #<(label+0)
* ldx #>(label+0)
* ldy #$xx
* clc
* adc (sp),y
* bcc L
* inx
* L: ldy #$00
* jsr ldauidx
*
* and replace it by:
*
* ldy #$xx
* ldx #$00
* lda (sp),y
* tay
* lda label,y
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[9];
unsigned Len;
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_LDA &&
L[0]->AM == AM65_IMM &&
CS_GetEntries (S, L+1, I+1, 8) &&
L[1]->OPC == OP65_LDX &&
L[1]->AM == AM65_IMM &&
!CE_HasLabel (L[1]) &&
L[2]->OPC == OP65_LDY &&
CE_KnownImm (L[2]) &&
!CE_HasLabel (L[2]) &&
L[3]->OPC == OP65_CLC &&
!CE_HasLabel (L[3]) &&
L[4]->OPC == OP65_ADC &&
L[4]->AM == AM65_ZP_INDY &&
!CE_HasLabel (L[4]) &&
(L[5]->OPC == OP65_BCC || L[5]->OPC == OP65_JCC) &&
L[5]->JumpTo != 0 &&
L[5]->JumpTo->Owner == L[7] &&
!CE_HasLabel (L[5]) &&
L[6]->OPC == OP65_INX &&
!CE_HasLabel (L[6]) &&
L[7]->OPC == OP65_LDY &&
CE_KnownImm (L[7]) &&
L[7]->Num == 0 &&
L[8]->OPC == OP65_JSR &&
strcmp (L[8]->Arg, "ldauidx") == 0 &&
!CE_HasLabel (L[8]) &&
/* Check the label last because this is quite costly */
(Len = strlen (L[0]->Arg)) > 3 &&
L[0]->Arg[0] == '<' &&
L[0]->Arg[1] == '(' &&
strlen (L[1]->Arg) == Len &&
L[1]->Arg[0] == '>' &&
memcmp (L[0]->Arg+1, L[1]->Arg+1, Len-1) == 0) {
CodeEntry* X;
char* Label;
/* Add the ldx */
X = NewCodeEntry (OP65_LDX, AM65_IMM, "$00", 0, L[0]->LI);
CS_InsertEntry (S, X, I+3);
/* Add the lda */
X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, L[4]->Arg, 0, L[0]->LI);
CS_InsertEntry (S, X, I+4);
/* Add the tay */
X = NewCodeEntry (OP65_TAY, AM65_IMP, 0, 0, L[0]->LI);
CS_InsertEntry (S, X, I+5);
/* Add the lda */
Label = memcpy (xmalloc (Len-2), L[0]->Arg+2, Len-3);
Label[Len-3] = '\0';
X = NewCodeEntry (OP65_LDA, AM65_ABSY, Label, 0, L[0]->LI);
CS_InsertEntry (S, X, I+6);
xfree (Label);
/* Remove the old code */
CS_DelEntries (S, I, 2);
CS_DelEntries (S, I+5, 6);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
static unsigned OptPtrLoad6 (CodeSeg* S)
/* Search for the sequence
*
* ldy ...
@ -2309,7 +2520,7 @@ typedef struct OptFunc OptFunc;
struct OptFunc {
unsigned (*Func) (CodeSeg*); /* Optimizer function */
const char* Name; /* Name of optimizer step */
unsigned char Type; /* Type of this step */
unsigned char Type; /* Type of this step */
char Disabled; /* True if pass disabled */
};
@ -2325,7 +2536,9 @@ static OptFunc OptFuncs [] = {
OptEntry (OptPtrLoad1, optPre),
OptEntry (OptPtrLoad2, optPre),
OptEntry (OptPtrLoad3, optPre),
OptEntry (OptPtrLoad4, optMain),
OptEntry (OptPtrLoad4, optPre),
OptEntry (OptPtrLoad5, optPre),
OptEntry (OptPtrLoad6, optMain),
/* Optimize calls to nega */
OptEntry (OptNegA1, optMain),
OptEntry (OptNegA2, optMain),