Optimize decaxn

git-svn-id: svn://svn.cc65.org/cc65/trunk@3726 b7a2c559-68d2-44c3-8de9-860c34a00d81

diff --git a/src/cc65/codeopt.c b/src/cc65/codeopt.c
index 4420fb8d6acc751a449b1612daeddd512ce2ae08..eef303e592964dca23ee6f6f8a629d101c3948e9 100644 (file)
--- a/src/cc65/codeopt.c
+++ b/src/cc65/codeopt.c
@@ -6,7 +6,7 @@
 /*                                                                           */
 /*                                                                           */
 /*                                                                           */
-/* (C) 2001-2003 Ullrich von Bassewitz                                       */
+/* (C) 2001-2006 Ullrich von Bassewitz                                       */
 /*               Römerstraße 52                                              */
 /*               D-70794 Filderstadt                                         */
 /* EMail:        uz@cc65.org                                                 */
@@ -1868,6 +1868,7 @@ static OptFunc DOptStore4       = { OptStore4,       "OptStore4",        50, 0,
 static OptFunc DOptStoreLoad           = { OptStoreLoad,    "OptStoreLoad",      0, 0, 0, 0, 0, 0 };
 static OptFunc DOptSub1                = { OptSub1,         "OptSub1",         100, 0, 0, 0, 0, 0 };
 static OptFunc DOptSub2                = { OptSub2,         "OptSub2",         100, 0, 0, 0, 0, 0 };
+static OptFunc DOptSub3                = { OptSub3,         "OptSub3",         100, 0, 0, 0, 0, 0 };
 static OptFunc DOptTest1               = { OptTest1,        "OptTest1",        100, 0, 0, 0, 0, 0 };
 static OptFunc DOptTransfers1          = { OptTransfers1,   "OptTransfers1",     0, 0, 0, 0, 0, 0 };
 static OptFunc DOptTransfers2          = { OptTransfers2,   "OptTransfers2",    60, 0, 0, 0, 0, 0 };
@@ -1941,6 +1942,7 @@ static OptFunc* OptFuncs[] = {
     &DOptStoreLoad,
     &DOptSub1,
     &DOptSub2,
+    &DOptSub3,
     &DOptTest1,
     &DOptTransfers1,
     &DOptTransfers2,
@@ -2245,6 +2247,7 @@ static unsigned RunOptGroup3 (CodeSeg* S)
                C += RunOptFunc (S, &DOptNegA2, 1);
                C += RunOptFunc (S, &DOptSub1, 1);
                C += RunOptFunc (S, &DOptSub2, 1);
+               C += RunOptFunc (S, &DOptSub3, 1);
                C += RunOptFunc (S, &DOptAdd5, 1);
                C += RunOptFunc (S, &DOptAdd6, 1);
                C += RunOptFunc (S, &DOptStackOps, 1);

diff --git a/src/cc65/coptsub.c b/src/cc65/coptsub.c
index cbd09caa0a9bcb9eab9e69151bdeca4b04d2e1ac..5449889f6228e5a9602dcc6ff6f5dbf317fcf7c0 100644 (file)
--- a/src/cc65/coptsub.c
+++ b/src/cc65/coptsub.c
@@ -6,10 +6,10 @@
 /*                                                                           */
 /*                                                                           */
 /*                                                                           */
-/* (C) 2001      Ullrich von Bassewitz                                       */
-/*               Wacholderweg 14                                             */
-/*               D-70597 Stuttgart                                           */
-/* EMail:        uz@cc65.org                                                 */
+/* (C) 2001-2006, Ullrich von Bassewitz                                      */
+/*                Römerstrasse 52                                            */
+/*                D-70794 Filderstadt                                        */
+/* EMail:         uz@cc65.org                                                */
 /*                                                                           */
 /*                                                                           */
 /* This software is provided 'as-is', without any expressed or implied       */
@@ -33,6 +33,9 @@
 
 
 
+/* common */
+#include "chartype.h"
+
 /* cc65 */
 #include "codeent.h"
 #include "codeinfo.h"
@@ -175,4 +178,56 @@ unsigned OptSub2 (CodeSeg* S)
 
 
 
+unsigned OptSub3 (CodeSeg* S)
+/* Search for a call to decaxn and replace it by an 8 bit sub if the X register
+ * is not used later.
+ */
+{
+    unsigned Changes = 0;
+
+    /* Walk over the entries */
+    unsigned I = 0;
+    while (I < CS_GetEntryCount (S)) {
+
+       CodeEntry* E;
+
+       /* Get next entry */
+               E = CS_GetEntry (S, I);
+
+       /* Check for the sequence */
+        if (E->OPC == OP65_JSR                          &&
+            strncmp (E->Arg, "decax", 5) == 0           &&
+            IsDigit (E->Arg[5])                         &&
+            E->Arg[6] == '\0'                           &&
+            !RegXUsed (S, I+1)) {
+
+            CodeEntry* X;
+            const char* Arg;
+
+            /* Insert new code behind the sequence */
+           X = NewCodeEntry (OP65_SEC, AM65_IMP, 0, 0, E->LI);
+           CS_InsertEntry (S, X, I+1);
+
+           Arg = MakeHexArg (E->Arg[5] - '0');
+                   X = NewCodeEntry (OP65_SBC, AM65_IMM, Arg, 0, E->LI);
+           CS_InsertEntry (S, X, I+2);
+
+                   /* Delete the old code */
+           CS_DelEntry (S, I);
+
+           /* Remember, we had changes */
+           ++Changes;
+
+       }
+
+       /* Next entry */
+       ++I;
+
+    }
+
+    /* Return the number of changes made */
+    return Changes;
+}
+
+
 

diff --git a/src/cc65/coptsub.h b/src/cc65/coptsub.h
index c9e40b8003946b5d51b7d8bb01c5324763392657..828a1d417b9b8f15b5385f64066534fd14b51310 100644 (file)
--- a/src/cc65/coptsub.h
+++ b/src/cc65/coptsub.h
@@ -6,10 +6,10 @@
 /*                                                                           */
 /*                                                                           */
 /*                                                                           */
-/* (C) 2001      Ullrich von Bassewitz                                       */
-/*               Wacholderweg 14                                             */
-/*               D-70597 Stuttgart                                           */
-/* EMail:        uz@cc65.org                                                 */
+/* (C) 2001-2006, Ullrich von Bassewitz                                      */
+/*                Römerstrasse 52                                            */
+/*                D-70794 Filderstadt                                        */
+/* EMail:         uz@cc65.org                                                */
 /*                                                                           */
 /*                                                                           */
 /* This software is provided 'as-is', without any expressed or implied       */
@@ -78,6 +78,11 @@ unsigned OptSub2 (CodeSeg* S);
  *      sta     yy
  */
 
+unsigned OptSub3 (CodeSeg* S);
+/* Search for a call to decaxn and replace it by an 8 bit sub if the X register
+ * is not used later.
+ */
+
 
 
 /* End of coptsub.h */