cc65/src/cc65/coptadd.c

556 lines
16 KiB
C

/*****************************************************************************/
/* */
/* coptadd.c */
/* */
/* Optimize addition sequences */
/* */
/* */
/* */
/* (C) 2001-2005, Ullrich von Bassewitz */
/* Roemerstrasse 52 */
/* D-70794 Filderstadt */
/* EMail: uz@cc65.org */
/* */
/* */
/* This software is provided 'as-is', without any expressed or implied */
/* warranty. In no event will the authors be held liable for any damages */
/* arising from the use of this software. */
/* */
/* Permission is granted to anyone to use this software for any purpose, */
/* including commercial applications, and to alter it and redistribute it */
/* freely, subject to the following restrictions: */
/* */
/* 1. The origin of this software must not be misrepresented; you must not */
/* claim that you wrote the original software. If you use this software */
/* in a product, an acknowledgment in the product documentation would be */
/* appreciated but is not required. */
/* 2. Altered source versions must be plainly marked as such, and must not */
/* be misrepresented as being the original software. */
/* 3. This notice may not be removed or altered from any source */
/* distribution. */
/* */
/*****************************************************************************/
/* common */
#include "chartype.h"
/* cc65 */
#include "codeent.h"
#include "codeinfo.h"
#include "coptadd.h"
/*****************************************************************************/
/* Optimize additions */
/*****************************************************************************/
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 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;
}
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 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 OptAdd5 (CodeSeg* S)
/* Search for a call to incaxn and replace it by an 8 bit add if the X register
** is not used later.
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* E;
/* Get next entry */
E = CS_GetEntry (S, I);
/* Check for the sequence */
if (E->OPC == OP65_JSR &&
strncmp (E->Arg, "incax", 5) == 0 &&
IsDigit (E->Arg[5]) &&
E->Arg[6] == '\0' &&
!RegXUsed (S, I+1)) {
CodeEntry* X;
const char* Arg;
/* Insert new code behind the sequence */
X = NewCodeEntry (OP65_CLC, AM65_IMP, 0, 0, E->LI);
CS_InsertEntry (S, X, I+1);
Arg = MakeHexArg (E->Arg[5] - '0');
X = NewCodeEntry (OP65_ADC, AM65_IMM, Arg, 0, E->LI);
CS_InsertEntry (S, X, I+2);
/* Delete the old code */
CS_DelEntry (S, I);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptAdd6 (CodeSeg* S)
/* Search for the sequence
**
** adc ...
** bcc L
** inx
** L:
**
** and remove the handling of the high byte if X is not used later.
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[3];
/* Get next entry */
CodeEntry* E = CS_GetEntry (S, I);
/* Check for the sequence */
if (E->OPC == OP65_ADC &&
CS_GetEntries (S, L, I+1, 3) &&
(L[0]->OPC == OP65_BCC || L[0]->OPC == OP65_JCC) &&
L[0]->JumpTo != 0 &&
!CE_HasLabel (L[0]) &&
L[1]->OPC == OP65_INX &&
!CE_HasLabel (L[1]) &&
L[0]->JumpTo->Owner == L[2] &&
!RegXUsed (S, I+3)) {
/* Remove the bcs/dex */
CS_DelEntries (S, I+1, 2);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}