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Reordered/splitted the optimization module

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git-svn-id: svn://svn.cc65.org/cc65/trunk@981 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
cuz 2001-09-29 11:09:25 +00:00
parent 2b07a07e57
commit 21111ba235
11 changed files with 1986 additions and 1402 deletions
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1612
src/cc65/codeopt.c
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src/cc65/coptadd.c Normal file
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/*****************************************************************************/
/* */
/* coptadd.c */
/* */
/* Optimize addition sequences */
/* */
/* */
/* */
/* (C) 2001 Ullrich von Bassewitz */
/* Wacholderweg 14 */
/* D-70597 Stuttgart */
/* 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. */
/* */
/*****************************************************************************/
#include <string.h>
/* common */
#include "xsprintf.h"
/* cc65 */
#include "codeent.h"
#include "codeinfo.h"
#include "coptadd.h"
/*****************************************************************************/
/* Optimize additions */
/*****************************************************************************/
unsigned OptAdd1 (CodeSeg* S)
/* Search for the sequence
*
* jsr pushax
* ldy xxx
* ldx #$00
* lda (sp),y
* jsr tosaddax
*
* and replace it by:
*
* ldy xxx-2
* clc
* adc (sp),y
* bcc L
* inx
* L:
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[5];
/* Get next entry */
CodeEntry* E = CS_GetEntry (S, I);
/* Check for the sequence */
if (E->OPC == OP65_JSR &&
strcmp (E->Arg, "pushax") == 0 &&
CS_GetEntries (S, L, I+1, 5) &&
L[0]->OPC == OP65_LDY &&
CE_KnownImm (L[0]) &&
!CE_HasLabel (L[0]) &&
L[1]->OPC == OP65_LDX &&
CE_KnownImm (L[1]) &&
L[1]->Num == 0 &&
!CE_HasLabel (L[1]) &&
L[2]->OPC == OP65_LDA &&
!CE_HasLabel (L[2]) &&
L[3]->OPC == OP65_JSR &&
strcmp (L[3]->Arg, "tosaddax") == 0 &&
!CE_HasLabel (L[3])) {
CodeEntry* X;
CodeLabel* Label;
/* Remove the call to pushax */
CS_DelEntry (S, I);
/* Correct the stack offset (needed since pushax was removed) */
CE_SetNumArg (L[0], L[0]->Num - 2);
/* Add the clc . */
X = NewCodeEntry (OP65_CLC, AM65_IMP, 0, 0, L[3]->LI);
CS_InsertEntry (S, X, I+1);
/* Remove the load */
CS_DelEntry (S, I+3); /* lda */
CS_DelEntry (S, I+2); /* ldx */
/* Add the adc */
X = NewCodeEntry (OP65_ADC, AM65_ZP_INDY, "sp", 0, L[3]->LI);
CS_InsertEntry (S, X, I+2);
/* Generate the branch label and the branch */
Label = CS_GenLabel (S, L[4]);
X = NewCodeEntry (OP65_BCC, AM65_BRA, Label->Name, Label, L[3]->LI);
CS_InsertEntry (S, X, I+3);
/* Generate the increment of the high byte */
X = NewCodeEntry (OP65_INX, AM65_IMP, 0, 0, L[3]->LI);
CS_InsertEntry (S, X, I+4);
/* Delete the call to tosaddax */
CS_DelEntry (S, I+5);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptAdd2 (CodeSeg* S)
/* Search for the sequence
*
* ldy #xx
* lda (sp),y
* tax
* dey
* lda (sp),y
* ldy #$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[7];
/* Get next entry */
L[0] = CS_GetEntry (S, I);
/* Check for the sequence */
if (L[0]->OPC == OP65_LDY &&
CE_KnownImm (L[0]) &&
CS_GetEntries (S, L+1, I+1, 6) &&
L[1]->OPC == OP65_LDA &&
L[1]->AM == AM65_ZP_INDY &&
!CE_HasLabel (L[1]) &&
L[2]->OPC == OP65_TAX &&
!CE_HasLabel (L[2]) &&
L[3]->OPC == OP65_DEY &&
!CE_HasLabel (L[3]) &&
L[4]->OPC == OP65_LDA &&
L[4]->AM == AM65_ZP_INDY &&
!CE_HasLabel (L[4]) &&
L[5]->OPC == OP65_LDY &&
CE_KnownImm (L[5]) &&
!CE_HasLabel (L[5]) &&
L[6]->OPC == OP65_JSR &&
strcmp (L[6]->Arg, "addeqysp") == 0 &&
!CE_HasLabel (L[6]) &&
(GetRegInfo (S, I+7, REG_AX) & REG_AX) == 0) {
char Buf [20];
CodeEntry* X;
/* Adjust the operand of the first LDY */
CE_SetNumArg (L[0], L[0]->Num - 1);
/* Load Y with the low offset of the target variable */
X = NewCodeEntry (OP65_LDY, AM65_IMM, L[5]->Arg, 0, L[1]->LI);
CS_InsertEntry (S, X, I+2);
/* Add the CLC */
X = NewCodeEntry (OP65_CLC, AM65_IMP, 0, 0, L[1]->LI);
CS_InsertEntry (S, X, I+3);
/* Remove the TAX/DEY sequence */
CS_DelEntry (S, I+5); /* dey */
CS_DelEntry (S, I+4); /* tax */
/* Addition of the low byte */
X = NewCodeEntry (OP65_ADC, AM65_ZP_INDY, "sp", 0, L[4]->LI);
CS_InsertEntry (S, X, I+4);
X = NewCodeEntry (OP65_STA, AM65_ZP_INDY, "sp", 0, L[4]->LI);
CS_InsertEntry (S, X, I+5);
/* LDY */
xsprintf (Buf, sizeof (Buf), "$%02X", (int) (L[0]->Num+1));
X = NewCodeEntry (OP65_LDY, AM65_IMM, Buf, 0, L[4]->LI);
CS_InsertEntry (S, X, I+6);
/* Addition of the high byte */
xsprintf (Buf, sizeof (Buf), "$%02X", (int)(L[5]->Num+1));
X = NewCodeEntry (OP65_LDY, AM65_IMM, Buf, 0, L[5]->LI);
CS_InsertEntry (S, X, I+8);
X = NewCodeEntry (OP65_ADC, AM65_ZP_INDY, "sp", 0, L[6]->LI);
CS_InsertEntry (S, X, I+9);
X = NewCodeEntry (OP65_STA, AM65_ZP_INDY, "sp", 0, L[6]->LI);
CS_InsertEntry (S, X, I+10);
/* Delete the remaining stuff */
CS_DelEntry (S, I+12);
CS_DelEntry (S, I+11);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptAdd3 (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;
}

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/*****************************************************************************/
/* */
/* coptadd.h */
/* */
/* Optimize addition sequences */
/* */
/* */
/* */
/* (C) 2001 Ullrich von Bassewitz */
/* Wacholderweg 14 */
/* D-70597 Stuttgart */
/* 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. */
/* */
/*****************************************************************************/
#ifndef COPTADD_H
#define COPTADD_H
/* cc65 */
#include "codeseg.h"
/*****************************************************************************/
/* Optimize additions */
/*****************************************************************************/
unsigned OptAdd1 (CodeSeg* S);
/* Search for the sequence
*
* jsr pushax
* ldy xxx
* ldx #$00
* lda (sp),y
* jsr tosaddax
*
* and replace it by:
*
* ldy xxx-2
* clc
* adc (sp),y
* bcc L
* inx
* L:
*/
unsigned OptAdd2 (CodeSeg* S);
/* Search for the sequence
*
* ldy #xx
* lda (sp),y
* tax
* dey
* lda (sp),y
* ldy #$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 OptAdd3 (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.
*/
/* End of coptadd.h */
#endif

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/*****************************************************************************/
/* */
/* coptcmp.c */
/* */
/* Optimize compares */
/* */
/* */
/* */
/* (C) 2001 Ullrich von Bassewitz */
/* Wacholderweg 14 */
/* D-70597 Stuttgart */
/* 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. */
/* */
/*****************************************************************************/
#include <string.h>
/* cc65 */
#include "codeent.h"
#include "codeinfo.h"
#include "error.h"
#include "coptcmp.h"
/*****************************************************************************/
/* Data */
/*****************************************************************************/
/* Defines for the conditions in a compare */
typedef enum {
CMP_INV = -1,
CMP_EQ,
CMP_NE,
CMP_GT,
CMP_GE,
CMP_LT,
CMP_LE,
CMP_UGT,
CMP_UGE,
CMP_ULT,
CMP_ULE
} cmp_t;
/* Table with the compare suffixes */
static const char CmpSuffixTab [][4] = {
"eq", "ne", "gt", "ge", "lt", "le", "ugt", "uge", "ult", "ule"
};
/* Table used to invert a condition, indexed by condition */
static const unsigned char CmpInvertTab [] = {
CMP_NE, CMP_EQ,
CMP_LE, CMP_LT, CMP_GE, CMP_GT,
CMP_ULE, CMP_ULT, CMP_UGE, CMP_UGT
};
/* Table to show which compares are signed (use the N flag) */
static const char CmpSignedTab [] = {
0, 0, 1, 1, 1, 1, 0, 0, 0, 0
};
/*****************************************************************************/
/* Helper functions */
/*****************************************************************************/
static cmp_t FindCmpCond (const char* Code, unsigned CodeLen)
/* Search for a compare condition by the given code using the given length */
{
unsigned I;
/* Linear search */
for (I = 0; I < sizeof (CmpSuffixTab) / sizeof (CmpSuffixTab [0]); ++I) {
if (strncmp (Code, CmpSuffixTab [I], CodeLen) == 0) {
/* Found */
return I;
}
}
/* Not found */
return CMP_INV;
}
static cmp_t FindBoolCmpCond (const char* Name)
/* Map a condition suffix to a code. Return the code or CMP_INV on failure */
{
/* Check for the correct subroutine name */
if (strncmp (Name, "bool", 4) == 0) {
/* Name is ok, search for the code in the table */
return FindCmpCond (Name+4, strlen(Name)-4);
} else {
/* Not found */
return CMP_INV;
}
}
static cmp_t FindTosCmpCond (const char* Name)
/* Check if this is a call to one of the TOS compare functions (tosgtax).
* Return the condition code or CMP_INV on failure.
*/
{
unsigned Len = strlen (Name);
/* Check for the correct subroutine name */
if (strncmp (Name, "tos", 3) == 0 && strcmp (Name+Len-2, "ax") == 0) {
/* Name is ok, search for the code in the table */
return FindCmpCond (Name+3, Len-3-2);
} else {
/* Not found */
return CMP_INV;
}
}
static void ReplaceCmp (CodeSeg* S, unsigned I, cmp_t Cond)
/* Helper function for the replacement of routines that return a boolean
* followed by a conditional jump. Instead of the boolean value, the condition
* codes are evaluated directly.
* I is the index of the conditional branch, the sequence is already checked
* to be correct.
*/
{
CodeEntry* N;
CodeLabel* L;
/* Get the entry */
CodeEntry* E = CS_GetEntry (S, I);
/* Replace the conditional branch */
switch (Cond) {
case CMP_EQ:
CE_ReplaceOPC (E, OP65_JEQ);
break;
case CMP_NE:
CE_ReplaceOPC (E, OP65_JNE);
break;
case CMP_GT:
/* Replace by
* beq @L
* jpl Target
* @L: ...
*/
if ((N = CS_GetNextEntry (S, I)) == 0) {
/* No such entry */
Internal ("Invalid program flow");
}
L = CS_GenLabel (S, N);
N = NewCodeEntry (OP65_BEQ, AM65_BRA, L->Name, L, E->LI);
CS_InsertEntry (S, N, I);
CE_ReplaceOPC (E, OP65_JPL);
break;
case CMP_GE:
CE_ReplaceOPC (E, OP65_JPL);
break;
case CMP_LT:
CE_ReplaceOPC (E, OP65_JMI);
break;
case CMP_LE:
/* Replace by
* jmi Target
* jeq Target
*/
CE_ReplaceOPC (E, OP65_JMI);
L = E->JumpTo;
N = NewCodeEntry (OP65_JEQ, AM65_BRA, L->Name, L, E->LI);
CS_InsertEntry (S, N, I+1);
break;
case CMP_UGT:
/* Replace by
* beq @L
* jcs Target
* @L: ...
*/
if ((N = CS_GetNextEntry (S, I)) == 0) {
/* No such entry */
Internal ("Invalid program flow");
}
L = CS_GenLabel (S, N);
N = NewCodeEntry (OP65_BEQ, AM65_BRA, L->Name, L, E->LI);
CS_InsertEntry (S, N, I);
CE_ReplaceOPC (E, OP65_JCS);
break;
case CMP_UGE:
CE_ReplaceOPC (E, OP65_JCS);
break;
case CMP_ULT:
CE_ReplaceOPC (E, OP65_JCC);
break;
case CMP_ULE:
/* Replace by
* jcc Target
* jeq Target
*/
CE_ReplaceOPC (E, OP65_JCC);
L = E->JumpTo;
N = NewCodeEntry (OP65_JEQ, AM65_BRA, L->Name, L, E->LI);
CS_InsertEntry (S, N, I+1);
break;
default:
Internal ("Unknown jump condition: %d", Cond);
}
}
static int IsImmCmp16 (CodeSeg* S, CodeEntry** L)
/* Check if the instructions at L are an immidiate compare of a/x:
*
*
*/
{
return (L[0]->OPC == OP65_CPX &&
L[0]->AM == AM65_IMM &&
(L[0]->Flags & CEF_NUMARG) != 0 &&
!CE_HasLabel (L[0]) &&
(L[1]->OPC == OP65_JNE || L[1]->OPC == OP65_BNE) &&
L[1]->JumpTo != 0 &&
!CE_HasLabel (L[1]) &&
L[2]->OPC == OP65_CMP &&
L[2]->AM == AM65_IMM &&
(L[2]->Flags & CEF_NUMARG) != 0 &&
(L[3]->Info & OF_ZBRA) != 0 &&
L[3]->JumpTo != 0 &&
(L[1]->JumpTo->Owner == L[3] || L[1]->JumpTo == L[3]->JumpTo));
}
static int GetCmpRegVal (const CodeEntry* E)
/* Return the register value for an immediate compare */
{
switch (E->OPC) {
case OP65_CMP: return E->RI->In.RegA;
case OP65_CPX: return E->RI->In.RegX;
case OP65_CPY: return E->RI->In.RegY;
default: Internal ("Invalid opcode in GetCmpRegVal");
return 0; /* Not reached */
}
}
static int IsCmpToZero (const CodeEntry* E)
/* Check if the given instrcuction is a compare to zero instruction */
{
return (E->OPC == OP65_CMP &&
E->AM == AM65_IMM &&
(E->Flags & CEF_NUMARG) != 0 &&
E->Num == 0);
}
static int IsSpLoad (const CodeEntry* E)
/* Return true if this is the load of A from the stack */
{
return E->OPC == OP65_LDA && E->AM == AM65_ZP_INDY && strcmp (E->Arg, "sp") == 0;
}
static int IsLocalLoad16 (CodeSeg* S, unsigned Index,
CodeEntry** L, unsigned Count)
/* Check if a 16 bit load of a local variable follows:
*
* ldy #$xx
* lda (sp),y
* tax
* dey
* lda (sp),y
*
* If so, read Count entries following the first ldy into L and return true
* if this is possible. Otherwise return false.
*/
{
/* Be sure we read enough entries for the check */
CHECK (Count >= 5);
/* Read the first entry */
L[0] = CS_GetEntry (S, Index);
/* Check for the sequence */
return (L[0]->OPC == OP65_LDY &&
L[0]->AM == AM65_IMM &&
(L[0]->Flags & CEF_NUMARG) != 0 &&
CS_GetEntries (S, L+1, Index+1, Count-1) &&
IsSpLoad (L[1]) &&
!CE_HasLabel (L[1]) &&
L[2]->OPC == OP65_TAX &&
!CE_HasLabel (L[2]) &&
L[3]->OPC == OP65_DEY &&
!CE_HasLabel (L[3]) &&
IsSpLoad (L[4]) &&
!CE_HasLabel (L[4]));
}
/*****************************************************************************/
/* Remove calls to the bool transformer subroutines */
/*****************************************************************************/
unsigned OptBoolTrans (CodeSeg* S)
/* Try to remove the call to boolean transformer routines where the call is
* not really needed.
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* N;
cmp_t Cond;
/* Get next entry */
CodeEntry* E = CS_GetEntry (S, I);
/* Check for a boolean transformer */
if (E->OPC == OP65_JSR &&
(Cond = FindBoolCmpCond (E->Arg)) != CMP_INV &&
(N = CS_GetNextEntry (S, I)) != 0 &&
(N->Info & OF_ZBRA) != 0) {
/* Make the boolean transformer unnecessary by changing the
* the conditional jump to evaluate the condition flags that
* are set after the compare directly. Note: jeq jumps if
* the condition is not met, jne jumps if the condition is met.
* Invert the code if we jump on condition not met.
*/
if (GetBranchCond (N->OPC) == BC_EQ) {
/* Jumps if condition false, invert condition */
Cond = CmpInvertTab [Cond];
}
/* Check if we can replace the code by something better */
ReplaceCmp (S, I+1, Cond);
/* Remove the call to the bool transformer */
CS_DelEntry (S, I);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
/*****************************************************************************/
/* Optimizations for compares */
/*****************************************************************************/
unsigned OptCmp1 (CodeSeg* S)
/* Search for the sequence
*
* stx xx
* stx tmp1
* ora tmp1
*
* and replace it by
*
* stx xx
* ora xx
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[2];
/* Get next entry */
CodeEntry* E = CS_GetEntry (S, I);
/* Check for the sequence */
if (E->OPC == OP65_STX &&
CS_GetEntries (S, L, I+1, 2) &&
L[0]->OPC == OP65_STX &&
strcmp (L[0]->Arg, "tmp1") == 0 &&
!CE_HasLabel (L[0]) &&
L[1]->OPC == OP65_ORA &&
strcmp (L[1]->Arg, "tmp1") == 0 &&
!CE_HasLabel (L[1])) {
/* Remove the remaining instructions */
CS_DelEntries (S, I+1, 2);
/* Insert the ora instead */
CS_InsertEntry (S, NewCodeEntry (OP65_ORA, E->AM, E->Arg, 0, E->LI), I+1);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptCmp2 (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[2];
/* Get next entry */
CodeEntry* E = CS_GetEntry (S, I);
/* Check for the sequence */
if ((E->OPC == OP65_ADC ||
E->OPC == OP65_AND ||
E->OPC == OP65_DEA ||
E->OPC == OP65_EOR ||
E->OPC == OP65_INA ||
E->OPC == OP65_LDA ||
E->OPC == OP65_ORA ||
E->OPC == OP65_PLA ||
E->OPC == OP65_SBC ||
E->OPC == OP65_TXA ||
E->OPC == OP65_TYA) &&
CS_GetEntries (S, L, I+1, 2) &&
IsCmpToZero (L[0]) &&
!CE_HasLabel (L[0]) &&
((L[1]->Info & OF_FBRA) != 0 ||
(L[1]->OPC == OP65_JSR &&
FindBoolCmpCond (L[1]->Arg) != CMP_INV)) &&
!CE_HasLabel (L[1])) {
/* Remove the compare */
CS_DelEntry (S, I+1);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptCmp3 (CodeSeg* S)
/* Search for
*
* lda x
* ldx y
* cpx #a
* bne L1
* cmp #b
* jne/jeq L2
*
* If a is zero, we may remove the compare. If a and b are both zero, we may
* replace it by the sequence
*
* lda x
* ora x+1
* jne/jeq ...
*
* L1 may be either the label at the branch instruction, or the target label
* of this instruction.
*/
{
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_GetEntries (S, L, I+1, 5) &&
L[0]->OPC == OP65_LDX &&
!CE_HasLabel (L[0]) &&
IsImmCmp16 (S, L+1)) {
if (L[1]->Num == 0 && L[3]->Num == 0) {
/* The value is zero, we may use the simple code version. */
CE_ReplaceOPC (L[0], OP65_ORA);
CS_DelEntries (S, I+2, 3);
} else {
/* Move the lda instruction after the first branch. This will
* improve speed, since the load is delayed after the first
* test.
*/
CS_MoveEntry (S, I, I+4);
/* We will replace the ldx/cpx by lda/cmp */
CE_ReplaceOPC (L[0], OP65_LDA);
CE_ReplaceOPC (L[1], OP65_CMP);
/* Beware: If the first LDA instruction had a label, we have
* to move this label to the top of the sequence again.
*/
if (CE_HasLabel (E)) {
CS_MoveLabels (S, E, L[0]);
}
}
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptCmp4 (CodeSeg* S)
/* Optimize compares of local variables:
*
* ldy #o
* lda (sp),y
* tax
* dey
* lda (sp),y
* cpx #a
* bne L1
* cmp #b
* jne/jeq L2
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[9];
/* Check for the sequence */
if (IsLocalLoad16 (S, I, L, 9) && IsImmCmp16 (S, L+5)) {
if (L[5]->Num == 0 && L[7]->Num == 0) {
/* The value is zero, we may use the simple code version:
* ldy #o
* lda (sp),y
* dey
* ora (sp),y
* jne/jeq ...
*/
CE_ReplaceOPC (L[4], OP65_ORA);
CS_DelEntries (S, I+5, 3); /* cpx/bne/cmp */
CS_DelEntry (S, I+2); /* tax */
} else {
/* Change the code to just use the A register. Move the load
* of the low byte after the first branch if possible:
*
* ldy #o
* lda (sp),y
* cmp #a
* bne L1
* dey
* lda (sp),y
* cmp #b
* jne/jeq ...
*/
CS_DelEntry (S, I+2); /* tax */
CE_ReplaceOPC (L[5], OP65_CMP); /* cpx -> cmp */
CS_MoveEntry (S, I+4, I+2); /* cmp */
CS_MoveEntry (S, I+5, I+3); /* bne */
}
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptCmp5 (CodeSeg* S)
/* Search for calls to compare subroutines followed by a conditional branch
* and replace them by cheaper versions, since the branch means that the
* boolean value returned by these routines is not needed (we may also check
* that explicitly, but for the current code generator it is always true).
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* N;
cmp_t Cond;
/* Get next entry */
CodeEntry* E = CS_GetEntry (S, I);
/* Check for the sequence */
if (E->OPC == OP65_JSR &&
(Cond = FindTosCmpCond (E->Arg)) != CMP_INV &&
(N = CS_GetNextEntry (S, I)) != 0 &&
(N->Info & OF_ZBRA) != 0 &&
!CE_HasLabel (N)) {
/* The tos... functions will return a boolean value in a/x and
* the Z flag says if this value is zero or not. We will call
* a cheaper subroutine instead, one that does not return a
* boolean value but only valid flags. Note: jeq jumps if
* the condition is not met, jne jumps if the condition is met.
* Invert the code if we jump on condition not met.
*/
if (GetBranchCond (N->OPC) == BC_EQ) {
/* Jumps if condition false, invert condition */
Cond = CmpInvertTab [Cond];
}
/* Replace the subroutine call. */
E = NewCodeEntry (OP65_JSR, AM65_ABS, "tosicmp", 0, E->LI);
CS_InsertEntry (S, E, I+1);
CS_DelEntry (S, I);
/* Replace the conditional branch */
ReplaceCmp (S, I+1, Cond);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptCmp6 (CodeSeg* S)
/* Search for a sequence ldx/txa/branch and remove the txa if A is not
* used later.
*/
{
unsigned Changes = 0;
/* Walk over the entries */
unsigned I = 0;
while (I < CS_GetEntryCount (S)) {
CodeEntry* L[2];
/* Get next entry */
CodeEntry* E = CS_GetEntry (S, I);
/* Check for the sequence */
if ((E->OPC == OP65_LDX) &&
CS_GetEntries (S, L, I+1, 2) &&
L[0]->OPC == OP65_TXA &&
!CE_HasLabel (L[0]) &&
(L[1]->Info & OF_FBRA) != 0 &&
!CE_HasLabel (L[1]) &&
!RegAUsed (S, I+3)) {
/* Remove the txa */
CS_DelEntry (S, I+1);
/* Remember, we had changes */
++Changes;
}
/* Next entry */
++I;
}
/* Return the number of changes made */
return Changes;
}
unsigned OptCmp7 (CodeSeg* S)
/* Check for register compares where the contents of the register and therefore
* the result of the compare is known.
*/
{
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)) {
int RegVal;
/* Get next entry */
CodeEntry* E = CS_GetEntry (S, I);
/* Check for a compare against an immediate value */
if ((E->Info & OF_CMP) != 0 &&
(RegVal = GetCmpRegVal (E)) >= 0 &&
CE_KnownImm (E)) {
/* We are able to evaluate the compare at compile time. Check if
* one or more branches are ahead.
*/
unsigned JumpsChanged = 0;
CodeEntry* N;
while ((N = CS_GetNextEntry (S, I)) != 0 && /* Followed by something.. */
(N->Info & OF_CBRA) != 0 && /* ..that is a cond branch.. */
!CE_HasLabel (N)) { /* ..and has no label */
/* Evaluate the branch condition */
int Cond;
switch (GetBranchCond (N->OPC)) {
case BC_CC:
Cond = ((unsigned char)RegVal) < ((unsigned char)E->Num);
break;
case BC_CS:
Cond = ((unsigned char)RegVal) >= ((unsigned char)E->Num);
break;
case BC_EQ:
Cond = ((unsigned char)RegVal) == ((unsigned char)E->Num);
break;
case BC_MI:
Cond = ((signed char)RegVal) < ((signed char)E->Num);
break;
case BC_NE:
Cond = ((unsigned char)RegVal) != ((unsigned char)E->Num);
break;
case BC_PL:
Cond = ((signed char)RegVal) >= ((signed char)E->Num);
break;
case BC_VC:
case BC_VS:
/* Not set by the compare operation, bail out (Note:
* Just skipping anything here is rather stupid, but
* the sequence is never generated by the compiler,
* so it's quite safe to skip).
*/
goto NextEntry;
default:
Internal ("Unknown branch condition");
}
/* If the condition is false, we may remove the jump. Otherwise
* the branch will always be taken, so we may replace it by a
* jump (and bail out).
*/
if (!Cond) {
CS_DelEntry (S, I+1);
} else {
CodeLabel* L = N->JumpTo;
CodeEntry* X = NewCodeEntry (OP65_JMP, AM65_BRA, L->Name, L, N->LI);
CS_InsertEntry (S, X, I+2);
CS_DelEntry (S, I+1);
}
/* Remember, we had changes */
++JumpsChanged;
++Changes;
}
/* If we have made changes above, we may also remove the compare */
if (JumpsChanged) {
CS_DelEntry (S, I);
}
}
NextEntry:
/* Next entry */
++I;
}
/* Free register info */
CS_FreeRegInfo (S);
/* Return the number of changes made */
return Changes;
}

151
src/cc65/coptcmp.h Normal file
View File

@ -0,0 +1,151 @@
/*****************************************************************************/
/* */
/* coptcmp.h */
/* */
/* Optimize compares */
/* */
/* */
/* */
/* (C) 2001 Ullrich von Bassewitz */
/* Wacholderweg 14 */
/* D-70597 Stuttgart */
/* 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. */
/* */
/*****************************************************************************/
#ifndef COPTCMP_H
#define COPTCMP_H
/* cc65 */
#include "codeseg.h"
/*****************************************************************************/
/* Remove calls to the bool transformer subroutines */
/*****************************************************************************/
unsigned OptBoolTrans (CodeSeg* S);
/* Try to remove the call to boolean transformer routines where the call is
* not really needed.
*/
/*****************************************************************************/
/* Optimizations for compares */
/*****************************************************************************/
unsigned OptCmp1 (CodeSeg* S);
/* Search for the sequence
*
* stx xx
* stx tmp1
* ora tmp1
*
* and replace it by
*
* stx xx
* ora xx
*/
unsigned OptCmp2 (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 OptCmp3 (CodeSeg* S);
/* Search for
*
* lda x
* ldx y
* cpx #a
* bne L1
* cmp #b
* jne/jeq L2
*
* If a is zero, we may remove the compare. If a and b are both zero, we may
* replace it by the sequence
*
* lda x
* ora x+1
* jne/jeq ...
*
* L1 may be either the label at the branch instruction, or the target label
* of this instruction.
*/
unsigned OptCmp4 (CodeSeg* S);
/* Optimize compares of local variables:
*
* ldy #o
* lda (sp),y
* tax
* dey
* lda (sp),y
* cpx #a
* bne L1
* cmp #b
* jne/jeq L2
*/
unsigned OptCmp5 (CodeSeg* S);
/* Search for calls to compare subroutines followed by a conditional branch
* and replace them by cheaper versions, since the branch means that the
* boolean value returned by these routines is not needed (we may also check
* that explicitly, but for the current code generator it is always true).
*/
unsigned OptCmp6 (CodeSeg* S);
/* Search for a sequence ldx/txa/branch and remove the txa if A is not
* used later.
*/
unsigned OptCmp7 (CodeSeg* S);
/* Check for register compares where the contents of the register and therefore
* the result of the compare is known.
*/
/* End of coptcmp.h */
#endif

2
src/cc65/coptind.c
View File

@ -691,7 +691,7 @@ unsigned OptUnusedStores (CodeSeg* S)
unsigned OptDuplicateLoads (CodeSeg* S)
unsigned OptDupLoads (CodeSeg* S)
/* Remove loads of registers where the value loaded is already in the register. */
{
unsigned Changes = 0;

2
src/cc65/coptind.h
View File

@ -93,7 +93,7 @@ unsigned OptUnusedLoads (CodeSeg* S);
unsigned OptUnusedStores (CodeSeg* S);
/* Remove stores into zero page registers that aren't used later */
unsigned OptDuplicateLoads (CodeSeg* S);
unsigned OptDupLoads (CodeSeg* S);
/* Remove loads of registers where the value loaded is already in the register. */
unsigned OptStoreLoad (CodeSeg* S);

184
src/cc65/coptsub.c Normal file
View File

@ -0,0 +1,184 @@
/*****************************************************************************/
/* */
/* coptsub.c */
/* */
/* Optimize subtraction sequences */
/* */
/* */
/* */
/* (C) 2001 Ullrich von Bassewitz */
/* Wacholderweg 14 */
/* D-70597 Stuttgart */
/* 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. */
/* */
/*****************************************************************************/
#include <string.h>
/* cc65 */
#include "codeent.h"
#include "codeinfo.h"
#include "coptsub.h"
/*****************************************************************************/
/* Optimize subtractions */
/*****************************************************************************/
unsigned OptSub1 (CodeSeg* S)
/* Search for the sequence
*
* sbc ...
* bcs L
* dex
* 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_SBC &&
CS_GetEntries (S, L, I+1, 3) &&
(L[0]->OPC == OP65_BCS || L[0]->OPC == OP65_JCS) &&
L[0]->JumpTo != 0 &&
!CE_HasLabel (L[0]) &&
L[1]->OPC == OP65_DEX &&
!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;
}
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_GetEntries (S, L, I+1, 5) &&
L[0]->OPC == OP65_SEC &&
!CE_HasLabel (L[0]) &&
L[1]->OPC == OP65_STA &&
strcmp (L[1]->Arg, "tmp1") == 0 &&
!CE_HasLabel (L[1]) &&
L[2]->OPC == OP65_LDA &&
!CE_HasLabel (L[2]) &&
L[3]->OPC == OP65_SBC &&
strcmp (L[3]->Arg, "tmp1") == 0 &&
!CE_HasLabel (L[3]) &&
L[4]->OPC == OP65_STA &&
strcmp (L[4]->Arg, L[2]->Arg) == 0 &&
!CE_HasLabel (L[4])) {
/* 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;
}

88
src/cc65/coptsub.h Normal file
View File

@ -0,0 +1,88 @@
/*****************************************************************************/
/* */
/* coptsub.h */
/* */
/* Optimize subtraction sequences */
/* */
/* */
/* */
/* (C) 2001 Ullrich von Bassewitz */
/* Wacholderweg 14 */
/* D-70597 Stuttgart */
/* 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. */
/* */
/*****************************************************************************/
#ifndef COPTSUB_H
#define COPTSUB_H
/* cc65 */
#include "codeseg.h"
/*****************************************************************************/
/* Optimize subtractions */
/*****************************************************************************/
unsigned OptSub1 (CodeSeg* S);
/* Search for the sequence
*
* sbc ...
* bcs L
* dex
* L:
*
* and remove the handling of the high byte if X is not used later.
*/
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
*/
/* End of coptsub.h */
#endif

5
src/cc65/make/gcc.mak
View File

@ -33,8 +33,11 @@ OBJS = anonname.o \
codeopt.o \
codeseg.o \
compile.o \
coptadd.o \
coptcmp.o \
coptind.o \
coptstop.o \
coptsub.o \
cpu.o \
dataseg.o \
datatype.o \
@ -106,4 +109,4 @@ depend dep: $(OBJS:.o=.c)
$(CC) -I$(COMMON) -MM $^ > .depend

6
src/cc65/make/watcom.mak
View File

@ -78,8 +78,11 @@ OBJS = anonname.obj \
codeopt.obj \
codeseg.obj \
compile.obj \
coptadd.obj \
coptcmp.obj \
coptind.obj \
coptstop.obj \
coptsub.obj \
cpu.obj \
dataseg.obj \
datatype.obj \
@ -148,8 +151,11 @@ FILE codeinfo.obj
FILE codeopt.obj
FILE codeseg.obj
FILE compile.obj
FILE coptadd.obj
FILE coptcmp.obj
FILE coptind.obj
FILE coptstop.obj
FILE coptsub.obj
FILE cpu.obj
FILE dataseg.obj
FILE datatype.obj