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;
+ /* Generate register info */
+ CS_GenRegInfo (S);
+
/* 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);
/* 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)) {
+ 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;
/* ldy #xx+1 */
- Arg = MakeHexArg (L[0]->Num+2);
+ Arg = MakeHexArg (L[0]->RI->In.RegY+2);
X = NewCodeEntry (OP65_LDY, AM65_IMM, Arg, 0, L[0]->LI);
- CS_InsertEntry (S, X, I+3);
+ 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);
+ 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, 2);
+
+ /* Remember, we had changes */
+ ++Changes;
+
+ }
+
+ /* Next entry */
+ ++I;
+
+ }
+
+ /* Free the register info */
+ CS_FreeRegInfo (S);
+
+ /* Return the number of changes made */
+ return Changes;
+}
+
+
+
+unsigned OptPush2 (CodeSeg* S)
+/* A sequence
+ *
+ * jsr ldaxidx
+ * jsr pushax
+ *
+ * may get replaced by
+ *
+ * jsr pushwidx
+ *
+ */
+{
+ unsigned I;
+ unsigned Changes = 0;
+
+ /* Generate register info */
+ CS_GenRegInfo (S);
+
+ /* 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, 3);
+ CS_DelEntries (S, I, 2);
/* Remember, we had changes */
++Changes;
}
+ /* Free the register info */
+ CS_FreeRegInfo (S);
+
/* Return the number of changes made */
return Changes;
}