fix genPlus bogus code generation demonstrated by Karl's eth.c

git-svn-id: https://sdcc.svn.sourceforge.net/svnroot/sdcc/trunk/sdcc@851 4a8a32a2-be11-0410-ad9d-d568d2c75423

diff --git a/src/ds390/gen.c b/src/ds390/gen.c
index 006cc10e235dc98a1fc4a54b0ff4e3cf0d613d96..0f7c943ad1cede334659abde9f5e561678fe19d1 100644 (file)
--- a/src/ds390/gen.c
+++ b/src/ds390/gen.c
@@ -3337,7 +3337,7 @@ genPlus (iCode * ic)
   _startLazyDPSEvaluation ();
   while (size--)
     {
-      if (AOP_TYPE (IC_LEFT (ic)) == AOP_ACC)
+      if (AOP_TYPE(IC_LEFT(ic)) == AOP_ACC && !AOP_NEEDSACC(IC_RIGHT(ic)))
        {
          MOVA (aopGet (AOP (IC_LEFT (ic)), offset, FALSE, FALSE, TRUE));
          if (offset == 0)
@@ -3349,13 +3349,33 @@ genPlus (iCode * ic)
        }
       else
        {
+         if (AOP_TYPE(IC_LEFT(ic)) == AOP_ACC && (offset == 0))
+         {
+             /* right is going to use ACC or we would have taken the
+              * above branch.
+              */
+             assert(AOP_NEEDSACC(IC_RIGHT(ic)));
+             D(emitcode(";", "+ AOP_ACC special case."););
+             emitcode("xch", "a, %s", DP2_RESULT_REG);
+         }
          MOVA (aopGet (AOP (IC_RIGHT (ic)), offset, FALSE, FALSE, TRUE));
          if (offset == 0)
-           emitcode ("add", "a,%s",
-                 aopGet (AOP (IC_LEFT (ic)), offset, FALSE, FALSE, FALSE));
+         {
+           if (AOP_TYPE(IC_LEFT(ic)) == AOP_ACC)
+           {
+               emitcode("add", "a, %s", DP2_RESULT_REG); 
+           }
+           else
+           {
+               emitcode ("add", "a,%s",
+                       aopGet (AOP(IC_LEFT(ic)), offset, FALSE, FALSE, FALSE));
+           }
+          }
          else
+         {
            emitcode ("addc", "a,%s",
                  aopGet (AOP (IC_LEFT (ic)), offset, FALSE, FALSE, FALSE));
+         }
        }
       if (!pushResult)
        {