65C02 optimizations

git-svn-id: svn://svn.cc65.org/cc65/trunk@548 b7a2c559-68d2-44c3-8de9-860c34a00d81

diff --git a/src/cc65/optimize.c b/src/cc65/optimize.c
index 4421a9bb6b1efc54b2bec39eea038e117bb7c91b..8889e4fb8b59a3d5f0eff710113c864cefebf673 100644 (file)
--- a/src/cc65/optimize.c
+++ b/src/cc65/optimize.c
@@ -4106,10 +4106,18 @@ static Line* OptOneBlock (Line* L)
                Delete = 1;
            } else if (LineMatch (L, "\tlda\t(")) {
                if (IsXAddrMode (L)) {
-                   /* lda (zp,x) - if Y and X are both zero, replace by
-                    * load indirect y and save one cycle in some cases.
+                   /* lda (zp,x). */
+                   /* If X is zero and we have a 65C02 cpu, replace it by
+                    * an indirect load.
                     */
-                   if (X == 0 && Y == 0) {
+                   if (X == 0 && CPU == CPU_65C02) { 
+                       unsigned Len = strlen (L->Line);
+                       L->Line [Len-3] = ')';
+                       L->Line [Len-2] = '\0';
+                           /* If Y and X are both zero, replace by load indirect
+                    * y and save one cycle in some cases.
+                    */
+                   } else if (X == 0 && Y == 0) {
                        char Buf [256];
                        const char* S = L->Line + 6;
                        char* T = Buf + 6;
@@ -4123,6 +4131,15 @@ static Line* OptOneBlock (Line* L)
                        *T   = '\0';
                        L = ReplaceLine (L, Buf);
                    }
+               } else if (IsYAddrMode (L)) {
+                   /* lda (zp),y. If Y is zero and we have a 65C02 CPU,
+                    * replace it by an indirect load.
+                    */
+                   if (Y == 0 && CPU == CPU_65C02) {
+                       unsigned Len = strlen (L->Line);
+                       L->Line [Len-3] = ')';
+                       L->Line [Len-2] = '\0';
+                   }
                }
                /* In any case invalidate A */
                A = -1;