More optimizations

git-svn-id: svn://svn.cc65.org/cc65/trunk@836 b7a2c559-68d2-44c3-8de9-860c34a00d81

diff --git a/src/cc65/codeopt.c b/src/cc65/codeopt.c
index 35edcab6c634faae0b3ddb3ddabe263d936ae120..e8a40cc915390009711cf289d23b0584838a79b6 100644 (file)
--- a/src/cc65/codeopt.c
+++ b/src/cc65/codeopt.c
@@ -1431,7 +1431,142 @@ static unsigned OptNegAX4 (CodeSeg* S)
 
 
 
+static unsigned OptPtrStore1Sub (CodeSeg* S, unsigned I, CodeEntry** const L)
+/* Check if this is one of the allowed suboperation for OptPtrStore1 */
+{
+    /* Check for a label attached to the entry */
+    if (CE_HasLabel (L[0])) {
+       return 0;
+    }
+
+    /* Check for single insn sub ops */
+    if (L[0]->OPC == OP65_AND                                           ||
+       L[0]->OPC == OP65_EOR                                           ||
+       L[0]->OPC == OP65_ORA                                           ||
+       (L[0]->OPC == OP65_JSR && strncmp (L[0]->Arg, "shlax", 5) == 0) ||
+               (L[0]->OPC == OP65_JSR && strncmp (L[0]->Arg, "shrax", 5) == 0)) {
+
+       /* One insn */
+       return 1;
+
+    } else if (L[0]->OPC == OP65_CLC                      &&
+                      (L[1] = CS_GetNextEntry (S, I)) != 0       &&
+              L[1]->OPC == OP65_ADC                      &&
+              !CE_HasLabel (L[1])) {
+       return 2;
+    } else if (L[0]->OPC == OP65_SEC                      &&
+              (L[1] = CS_GetNextEntry (S, I)) != 0       &&
+              L[1]->OPC == OP65_SBC                      &&
+              !CE_HasLabel (L[1])) {
+       return 2;
+    }
+
+
+
+    /* Not found */
+    return 0;
+}
+
+
+
 static unsigned OptPtrStore1 (CodeSeg* S)
+/* Search for the sequence:
+ *
+ *     jsr     pushax
+ *      ldy     xxx
+ *      jsr     ldauidx
+ *      subop
+ *      ldy     yyy
+ *     jsr     staspidx
+ *
+ * and replace it by:
+ *
+ *      sta     ptr1
+ *      stx     ptr1+1
+ *      ldy     xxx
+ *      ldx     #$00
+ *      lda     (ptr1),y
+ *     subop
+ *      ldy     yyy
+ *      sta     (ptr1),y
+ */
+{
+    unsigned Changes = 0;
+
+    /* Walk over the entries */
+    unsigned I = 0;
+    while (I < CS_GetEntryCount (S)) {
+
+       unsigned K;
+       CodeEntry* L[10];
+
+       /* Get next entry */
+               L[0] = CS_GetEntry (S, I);
+
+       /* Check for the sequence */
+               if (L[0]->OPC == OP65_JSR                   &&
+           strcmp (L[0]->Arg, "pushax") == 0       &&
+                   CS_GetEntries (S, L+1, I+1, 3)          &&
+                   L[1]->OPC == OP65_LDY                   &&
+           CE_KnownImm (L[1])                      &&
+           !CE_HasLabel (L[1])                     &&
+           L[2]->OPC == OP65_JSR                   &&
+           strcmp (L[2]->Arg, "ldauidx") == 0      &&
+           !CE_HasLabel (L[2])                     &&
+                   (K = OptPtrStore1Sub (S, I+3, L+3)) > 0 &&
+           CS_GetEntries (S, L+3+K, I+3+K, 2)      &&
+                   L[3+K]->OPC == OP65_LDY                 &&
+           CE_KnownImm (L[3+K])                    &&
+           !CE_HasLabel (L[3+K])                   &&
+           L[4+K]->OPC == OP65_JSR                 &&
+           strcmp (L[4+K]->Arg, "staspidx") == 0   &&
+           !CE_HasLabel (L[4+K])) {
+
+           CodeEntry* X;
+
+           /* Create and insert the stores */
+                   X = NewCodeEntry (OP65_STA, AM65_ZP, "ptr1", 0, L[0]->LI);
+           CS_InsertEntry (S, X, I+1);
+
+           X = NewCodeEntry (OP65_STX, AM65_ZP, "ptr1+1", 0, L[0]->LI);
+           CS_InsertEntry (S, X, I+2);
+
+           /* Delete the call to pushax */
+           CS_DelEntry (S, I);
+
+           /* Delete the call to ldauidx */
+           CS_DelEntry (S, I+3);
+
+           /* Insert the load from ptr1 */
+           X = NewCodeEntry (OP65_LDX, AM65_IMM, "$00", 0, L[3]->LI);
+           CS_InsertEntry (S, X, I+3);
+           X = NewCodeEntry (OP65_LDA, AM65_ZP_INDY, "ptr1", 0, L[2]->LI);
+           CS_InsertEntry (S, X, I+4);
+
+           /* Insert the store through ptr1 */
+           X = NewCodeEntry (OP65_STA, AM65_ZP_INDY, "ptr1", 0, L[3]->LI);
+           CS_InsertEntry (S, X, I+6+K);
+
+           /* Delete the call to staspidx */
+           CS_DelEntry (S, I+7+K);
+
+           /* Remember, we had changes */
+           ++Changes;
+
+       }
+
+       /* Next entry */
+       ++I;
+
+    }
+
+    /* Return the number of changes made */
+    return Changes;
+}
+
+
+
+static unsigned OptPtrStore2 (CodeSeg* S)
 /* Search for the sequence:
  *
  *     jsr     pushax
@@ -1693,12 +1828,13 @@ struct OptFunc {
 static OptFunc OptFuncs [] = {
     /* Optimizes stores through pointers */
     OptEntry (OptPtrStore1, optPre),
+    OptEntry (OptPtrStore2, optPre),
     /* Optimize loads through pointers */
     OptEntry (OptPtrLoad1, optMain),
     OptEntry (OptPtrLoad2, optMain),
     /* Optimize calls to nega */
-    OptEntry (OptNegA1, optPre),
-    OptEntry (OptNegA2, optPre),
+    OptEntry (OptNegA1, optMain),
+    OptEntry (OptNegA2, optMain),
     /* Optimize calls to negax */
     OptEntry (OptNegAX1, optPre),
     OptEntry (OptNegAX2, optPre),