/*****************************************************************************/
/* */
-/* coptpush.c */
+/* coptpush.c */
/* */
-/* Optimize push sequences */
+/* Optimize push sequences */
/* */
/* */
/* */
-/* (C) 2001-2002 Ullrich von Bassewitz */
-/* Wacholderweg 14 */
-/* D-70597 Stuttgart */
-/* EMail: uz@cc65.org */
+/* (C) 2001-2012, Ullrich von Bassewitz */
+/* Roemerstrasse 52 */
+/* D-70794 Filderstadt */
+/* EMail: uz@cc65.org */
/* */
/* */
/* This software is provided 'as-is', without any expressed or implied */
/*****************************************************************************/
-/* Code */
+/* Code */
/*****************************************************************************/
unsigned OptPush1 (CodeSeg* S)
/* Given a sequence
*
- * ldy #xx
* jsr ldaxysp
* jsr pushax
*
- * If a/x are not used later, replace that by
+ * If a/x are not used later, and Y is known, replace that by
*
* ldy #xx+2
* jsr pushwysp
* saving 3 bytes and several cycles.
*/
{
+ unsigned I;
unsigned Changes = 0;
/* Walk over the entries */
- unsigned I = 0;
+ I = 0;
while (I < CS_GetEntryCount (S)) {
- CodeEntry* L[3];
+ CodeEntry* L[2];
- /* Get next entry */
- L[0] = CS_GetEntry (S, I);
+ /* Get next entry */
+ L[0] = CS_GetEntry (S, I);
- /* Check for the sequence */
- if (L[0]->OPC == OP65_LDY &&
- CE_KnownImm (L[0]) &&
- L[0]->Num < 0xFE &&
- !CS_RangeHasLabel (S, I+1, 2) &&
- CS_GetEntries (S, L+1, I+1, 2) &&
- CE_IsCallTo (L[1], "ldaxysp") &&
- CE_IsCallTo (L[2], "pushax") &&
- !RegAXUsed (S, I+3)) {
+ /* Check for the sequence */
+ if (CE_IsCallTo (L[0], "ldaxysp") &&
+ RegValIsKnown (L[0]->RI->In.RegY) &&
+ L[0]->RI->In.RegY < 0xFE &&
+ (L[1] = CS_GetNextEntry (S, I)) != 0 &&
+ !CE_HasLabel (L[1]) &&
+ CE_IsCallTo (L[1], "pushax") &&
+ !RegAXUsed (S, I+2)) {
- /* Insert new code behind the pushax */
- const char* Arg;
- CodeEntry* X;
+ /* Insert new code behind the pushax */
+ const char* Arg;
+ CodeEntry* X;
- /* ldy #xx+1 */
- Arg = MakeHexArg (L[0]->Num+2);
- X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, L[0]->LI);
- CS_InsertEntry (S, X, I+3);
+ /* ldy #xx+1 */
+ Arg = MakeHexArg (L[0]->RI->In.RegY+2);
+ X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, L[0]->LI);
+ CS_InsertEntry (S, X, I+2);
- /* jsr pushwysp */
- X = NewCodeEntry (OP65_JSR, AM65_ABS, "pushwysp", 0, L[2]->LI);
- CS_InsertEntry (S, X, I+4);
+ /* jsr pushwysp */
+ X = NewCodeEntry (OP65_JSR, AM65_ABS, "pushwysp", 0, L[1]->LI);
+ CS_InsertEntry (S, X, I+3);
- /* Delete the old code */
- CS_DelEntries (S, I, 3);
+ /* Delete the old code */
+ CS_DelEntries (S, I, 2);
- /* Remember, we had changes */
- ++Changes;
+ /* Remember, we had changes */
+ ++Changes;
- }
+ }
- /* Next entry */
- ++I;
+ /* Next entry */
+ ++I;
}
+unsigned OptPush2 (CodeSeg* S)
+/* A sequence
+ *
+ * jsr ldaxidx
+ * jsr pushax
+ *
+ * may get replaced by
+ *
+ * jsr pushwidx
+ *
+ */
+{
+ unsigned I;
+ unsigned Changes = 0;
+
+ /* Walk over the entries */
+ I = 0;
+ while (I < CS_GetEntryCount (S)) {
+
+ CodeEntry* L[2];
+
+ /* Get next entry */
+ L[0] = CS_GetEntry (S, I);
+
+ /* Check for the sequence */
+ if (CE_IsCallTo (L[0], "ldaxidx") &&
+ (L[1] = CS_GetNextEntry (S, I)) != 0 &&
+ !CE_HasLabel (L[1]) &&
+ CE_IsCallTo (L[1], "pushax")) {
+
+ /* Insert new code behind the pushax */
+ CodeEntry* X;
+
+ /* jsr pushwidx */
+ X = NewCodeEntry (OP65_JSR, AM65_ABS, "pushwidx", 0, L[1]->LI);
+ CS_InsertEntry (S, X, I+2);
+
+ /* Delete the old code */
+ CS_DelEntries (S, I, 2);
+
+ /* Remember, we had changes */
+ ++Changes;
+
+ }
+
+ /* Next entry */
+ ++I;
+
+ }
+
+ /* Return the number of changes made */
+ return Changes;
+}