* src/SDCCcse.c (algebraicOpts): fixed loss of volatility

  for fields at offset 0 of a struct or union as reported
  on 2005-07-07 in the developer mailing list.

git-svn-id: https://sdcc.svn.sourceforge.net/svnroot/sdcc/trunk/sdcc@3803 4a8a32a2-be11-0410-ad9d-d568d2c75423

diff --git a/ChangeLog b/ChangeLog
index b4ab4ce2a4eed5d4533cdea1e57a17b18c29d1f1..b6e9d1d673f0cc3251c74c2b64e655222001f24d 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2005-07-16 Erik Petrich <epetrich AT ivorytower.norman.ok.us>
+
+       * src/SDCCcse.c (algebraicOpts): fixed loss of volatility
+         for fields at offset 0 of a struct or union as reported
+         on 2005-07-07 in the developer mailing list.
+
 2005-07-15 Maarten Brock <sourceforge.brock AT dse.nl>
 
        * src/SDCCmem.c: fixed bug 1238386

diff --git a/src/SDCCcse.c b/src/SDCCcse.c
index 83863baa234830078142284f6f23996615e10d52..8e68739ec2487a728c631120b6c3dcb3bc686752 100644 (file)
--- a/src/SDCCcse.c
+++ b/src/SDCCcse.c
@@ -829,8 +829,10 @@ algebraicOpts (iCode * ic, eBBlock * ebp)
       if (IS_OP_LITERAL (IC_LEFT (ic)) &&
           operandLitValue (IC_LEFT (ic)) == 0.0)
         {
-          if (compareType (operandType (IC_RESULT (ic)),
-                           operandType (IC_RIGHT (ic)))<0)
+          int typematch;
+          typematch = compareType (operandType (IC_RESULT (ic)),
+                                   operandType (IC_RIGHT (ic)));
+          if (typematch<0)
             {
               ic->op = CAST;
               IC_LEFT (ic) = operandFromLink (operandType (IC_RESULT (ic)));
@@ -839,6 +841,12 @@ algebraicOpts (iCode * ic, eBBlock * ebp)
             {
               ic->op = '=';
               IC_LEFT (ic) = NULL;
+              if (typematch==0)
+                {
+                  /* for completely different types, preserve the source type */
+                  IC_RIGHT (ic) = operandFromOperand (IC_RIGHT (ic));
+                  setOperandType (IC_RIGHT (ic), operandType (IC_RESULT (ic)));
+                }
             }
           SET_ISADDR (IC_RESULT (ic), 0);
           SET_ISADDR (IC_RIGHT (ic), 0);
@@ -847,8 +855,10 @@ algebraicOpts (iCode * ic, eBBlock * ebp)
       if (IS_OP_LITERAL (IC_RIGHT (ic)) &&
           operandLitValue (IC_RIGHT (ic)) == 0.0)
         {
-          if (compareType (operandType (IC_RESULT (ic)),
-                           operandType (IC_LEFT (ic)))<0)
+          int typematch;
+          typematch = compareType (operandType (IC_RESULT (ic)),
+                                   operandType (IC_LEFT (ic)));
+          if (typematch<0)
             {
               ic->op = CAST;
               IC_RIGHT (ic) = IC_LEFT (ic);
@@ -859,6 +869,12 @@ algebraicOpts (iCode * ic, eBBlock * ebp)
               ic->op = '=';
               IC_RIGHT (ic) = IC_LEFT (ic);
               IC_LEFT (ic) = NULL;
+              if (typematch==0)
+                {
+                  /* for completely different types, preserve the source type */
+                  IC_RIGHT (ic) = operandFromOperand (IC_RIGHT (ic));
+                  setOperandType (IC_RIGHT (ic), operandType (IC_RESULT (ic)));
+                }
             }
           SET_ISADDR (IC_RIGHT (ic), 0);
           SET_ISADDR (IC_RESULT (ic), 0);