Fixed the incorrect caching of pointer reference in a loop containing function call

git-svn-id: https://sdcc.svn.sourceforge.net/svnroot/sdcc/trunk/sdcc@710 4a8a32a2-be11-0410-ad9d-d568d2c75423

diff --git a/src/SDCCloop.c b/src/SDCCloop.c
index ef79a6b90a0df3a210ef3fb3bf002723343ff1c8..6a5b239fcb5be9b961f5f1c477a39c79dfef49cd 100644 (file)
--- a/src/SDCCloop.c
+++ b/src/SDCCloop.c
@@ -408,6 +408,7 @@ loopInvariants (region * theLoop, eBBlock ** ebbs, int count)
   set *lInvars = NULL;
 
   int change = 0;
+  int fCallsInBlock;
 
   /* if the preHeader does not exist then do nothing */
   /* or no exits then do nothing ( have to think about this situation */
@@ -429,6 +430,12 @@ loopInvariants (region * theLoop, eBBlock ** ebbs, int count)
       domsAllExits = (applyToSet (theLoop->exits, dominatedBy, lBlock) ==
                      elementsInSet (theLoop->exits));
 
+      /* find out if we have a function call in this block */
+      for (ic = lBlock->sch, fCallsInBlock=0; ic; ic = ic->next) {
+       if (SKIP_IC(ic)) {
+         fCallsInBlock++;
+       }
+      }
 
       /* now we go thru the instructions of this block and */
       /* collect those instructions with invariant operands */
@@ -438,6 +445,13 @@ loopInvariants (region * theLoop, eBBlock ** ebbs, int count)
          int lin, rin;
          cseDef *ivar;
 
+         /* if there are function calls in this block and this
+            is a pointer get, the function could have changed it
+            so skip, ISO-C99 according to David A. Long */
+         if (fCallsInBlock && POINTER_GET(ic)) {
+           continue;
+         }
+
          if (SKIP_IC (ic) || POINTER_SET (ic) || ic->op == IFX)
            continue;
 
@@ -453,26 +467,28 @@ loopInvariants (region * theLoop, eBBlock ** ebbs, int count)
            continue;
 
          lin = rin = 0;
-
+         
          /* special case */
          /* if address of then it is an invariant */
          if (ic->op == ADDRESS_OF &&
              IS_SYMOP (IC_LEFT (ic)) &&
              IS_AGGREGATE (operandType (IC_LEFT (ic))))
            lin++;
-         else
+         else {
            /* check if left operand is an invariant */
-         if ((lin = isOperandInvariant (IC_LEFT (ic), theLoop, lInvars)))
-           /* if this is a pointer get then make sure
-              that the pointer set does not exist in
-              any of the blocks */
-           if (POINTER_GET (ic) &&
-           (applyToSet (theLoop->regBlocks, pointerAssigned, IC_LEFT (ic))))
-             lin = 0;
-
+           if ((lin = isOperandInvariant (IC_LEFT (ic), theLoop, lInvars)))
+             /* if this is a pointer get then make sure
+                that the pointer set does not exist in
+                any of the blocks */
+             if (POINTER_GET (ic) &&
+                 (applyToSet (theLoop->regBlocks, 
+                              pointerAssigned, IC_LEFT (ic))))
+               lin = 0;
+         }
+         
          /* do the same for right */
          rin = isOperandInvariant (IC_RIGHT (ic), theLoop, lInvars);
-
+         
          /* if this is a POINTER_GET then special case, make sure all
             usages within the loop are POINTER_GET any other usage
             would mean that this is not an invariant , since the pointer