added DUMMY_READ_VOLATILE:

[fw/sdcc] / src / SDCCcse.c

diff --git a/src/SDCCcse.c b/src/SDCCcse.c
index 16553d4a748edd9e92fbc736f4a29363be65f94d..a25b9f488ff8f08b525c8d12711c3f66213df829 100644 (file)
--- a/src/SDCCcse.c
+++ b/src/SDCCcse.c
@@ -633,8 +633,8 @@ iCode *findBackwardDef(operand *op,iCode *ic)
 /*-----------------------------------------------------------------*/
 /* algebraicOpts - does some algebraic optimizations               */
 /*-----------------------------------------------------------------*/
-void 
-algebraicOpts (iCode * ic)
+static void
+algebraicOpts (iCode * ic, eBBlock * ebp)
 {
   /* we don't deal with the following iCodes
      here */
@@ -951,29 +951,30 @@ algebraicOpts (iCode * ic)
        }
       break;
     case BITWISEAND:
-      if (IS_OP_LITERAL (IC_LEFT (ic)))
+      /* if both operands are equal */
+      /* if yes turn it into assignment */
+      if (isOperandEqual (IC_LEFT (ic), IC_RIGHT (ic)))
         {
-         /* if BITWISEAND then check if one of them is a zero */
-         /* if yes turn it into 0 assignment */
-         if (operandLitValue (IC_LEFT (ic)) == 0.0)
+          if (IS_OP_VOLATILE (IC_LEFT (ic)))
            {
-             if (IS_OP_VOLATILE (IC_RIGHT (ic)))
-               return;
-             ic->op = '=';
-             IC_RIGHT (ic) = IC_LEFT (ic);
-             IC_LEFT (ic) = NULL;
-             SET_RESULT_RIGHT (ic);
-             return;
-           }
-         /* if BITWISEAND then check if one of them is 0xff... */
-         /* if yes turn it into assignment */
-         if (operandLitValue (IC_LEFT (ic)) == -1.0)
-           {
-             ic->op = '=';
-             IC_LEFT (ic) = NULL;
-             SET_RESULT_RIGHT (ic);
-             return;
+             iCode *newic = newiCode (DUMMY_READ_VOLATILE, NULL, IC_LEFT (ic));
+             IC_RESULT (newic) = IC_LEFT (ic);
+             newic->lineno = ic->lineno;
+             addiCodeToeBBlock (ebp, newic, ic->next);
            }
+         ic->op = '=';
+         IC_LEFT (ic) = NULL;
+         SET_RESULT_RIGHT (ic);
+         return;
+       }
+      /* swap literal to right ic */
+      if (IS_OP_LITERAL (IC_LEFT (ic)))
+        {
+         operand *op;
+
+         op = IC_LEFT (ic);
+         IC_LEFT (ic) = IC_RIGHT (ic);
+         IC_RIGHT (ic) = op;
        }
       if (IS_OP_LITERAL (IC_RIGHT (ic)))
         {
@@ -982,7 +983,12 @@ algebraicOpts (iCode * ic)
          if (operandLitValue (IC_RIGHT (ic)) == 0.0)
            {
              if (IS_OP_VOLATILE (IC_LEFT (ic)))
-               return;
+               {
+                 iCode *newic = newiCode (DUMMY_READ_VOLATILE, NULL, IC_LEFT (ic));
+                 IC_RESULT (newic) = IC_LEFT (ic);
+                 newic->lineno = ic->lineno;
+                 addiCodeToeBBlock (ebp, newic, ic->next);
+               }
              ic->op = '=';
              IC_LEFT (ic) = NULL;
              SET_RESULT_RIGHT (ic);
@@ -990,7 +996,24 @@ algebraicOpts (iCode * ic)
            }
          /* if BITWISEAND then check if one of them is 0xff... */
          /* if yes turn it into assignment */
-         if (operandLitValue (IC_RIGHT (ic)) == -1.0)
+         {
+           long val;
+
+           switch (getSize (operandType (IC_RIGHT (ic))))
+             {
+             case 1:
+               val = 0xff;
+               break;
+             case 2:
+               val = 0xffff;
+               break;
+             case 4:
+               val = 0xffffffff;
+               break;
+             default:
+               return;
+             }
+           if (((long) operandLitValue (IC_RIGHT (ic)) & val) == val)
            {
              ic->op = '=';
              IC_RIGHT (ic) = IC_LEFT (ic);
@@ -998,30 +1021,34 @@ algebraicOpts (iCode * ic)
              SET_RESULT_RIGHT (ic);
              return;
            }
+         }
        }
       break;
     case '|':
-      if (IS_OP_LITERAL (IC_LEFT (ic)))
+      /* if both operands are equal */
+      /* if yes turn it into assignment */
+      if (isOperandEqual (IC_LEFT (ic), IC_RIGHT (ic)))
         {
-         /* if BITWISEOR then check if one of them is a zero */
-         /* if yes turn it into assignment */
-         if (operandLitValue (IC_LEFT (ic)) == 0.0)
+          if (IS_OP_VOLATILE (IC_LEFT (ic)))
            {
-             ic->op = '=';
-             IC_LEFT (ic) = NULL;
-             SET_RESULT_RIGHT (ic);
-             return;
-           }
-         /* if BITWISEOR then check if one of them is 0xff... */
-         /* if yes turn it into 0xff... assignment */
-         if (operandLitValue (IC_LEFT (ic)) == -1.0)
-           {
-             ic->op = '=';
-             IC_RIGHT (ic) = IC_LEFT (ic);
-             IC_LEFT (ic) = NULL;
-             SET_RESULT_RIGHT (ic);
-             return;
+             iCode *newic = newiCode (DUMMY_READ_VOLATILE, NULL, IC_LEFT (ic));
+             IC_RESULT (newic) = IC_LEFT (ic);
+             newic->lineno = ic->lineno;
+             addiCodeToeBBlock (ebp, newic, ic->next);
            }
+           ic->op = '=';
+           IC_LEFT (ic) = NULL;
+           SET_RESULT_RIGHT (ic);
+           return;
+       }
+      /* swap literal to right ic */
+      if (IS_OP_LITERAL (IC_LEFT (ic)))
+        {
+         operand *op;
+
+         op = IC_LEFT (ic);
+         IC_LEFT (ic) = IC_RIGHT (ic);
+         IC_RIGHT (ic) = op;
        }
       if (IS_OP_LITERAL (IC_RIGHT (ic)))
         {
@@ -1037,34 +1064,84 @@ algebraicOpts (iCode * ic)
            }
          /* if BITWISEOR then check if one of them is 0xff... */
          /* if yes turn it into 0xff... assignment */
-         if (operandLitValue (IC_RIGHT (ic)) == -1.0)
-           {
-             ic->op = '=';
-             IC_LEFT (ic) = NULL;
-             SET_RESULT_RIGHT (ic);
-             return;
-           }
+         {
+           long val;
+
+           switch (getSize (operandType (IC_RIGHT (ic))))
+             {
+             case 1:
+               val = 0xff;
+               break;
+             case 2:
+               val = 0xffff;
+               break;
+             case 4:
+               val = 0xffffffff;
+               break;
+             default:
+               return;
+             }
+           if (((long) operandLitValue (IC_RIGHT (ic)) & val) == val)
+             {
+               if (IS_OP_VOLATILE (IC_LEFT (ic)))
+               {
+                 iCode *newic = newiCode (DUMMY_READ_VOLATILE, NULL, IC_LEFT (ic));
+                 IC_RESULT (newic) = IC_LEFT (ic);
+                 newic->lineno = ic->lineno;
+                 addiCodeToeBBlock (ebp, newic, ic->next);
+               }
+               ic->op = '=';
+               IC_LEFT (ic) = NULL;
+               SET_RESULT_RIGHT (ic);
+               return;
+             }
+         }
        }
       break;
     case '^':
+      /* if both operands are equal */
+      /* if yes turn it into 0 assignment */
+      if (isOperandEqual (IC_LEFT (ic), IC_RIGHT (ic)))
+        {
+          if (IS_OP_VOLATILE (IC_LEFT (ic)))
+           {
+             iCode *newic = newiCode (DUMMY_READ_VOLATILE, NULL, IC_LEFT (ic));
+             IC_RESULT (newic) = IC_LEFT (ic);
+             newic->lineno = ic->lineno;
+             addiCodeToeBBlock (ebp, newic, ic->next);
+
+             newic = newiCode (DUMMY_READ_VOLATILE, NULL, IC_LEFT (ic));
+             IC_RESULT (newic) = IC_LEFT (ic);
+             newic->lineno = ic->lineno;
+             addiCodeToeBBlock (ebp, newic, ic->next);
+           }
+           ic->op = '=';
+           IC_RIGHT (ic) = operandFromLit (0);
+           IC_LEFT (ic) = NULL;
+           SET_RESULT_RIGHT (ic);
+           return;
+       }
+      /* swap literal to right ic */
+      if (IS_OP_LITERAL (IC_LEFT (ic)))
+        {
+         operand *op;
+
+         op = IC_LEFT (ic);
+         IC_LEFT (ic) = IC_RIGHT (ic);
+         IC_RIGHT (ic) = op;
+       }
       /* if XOR then check if one of them is a zero */
       /* if yes turn it into assignment */
-      if (IS_OP_LITERAL (IC_LEFT (ic)) &&
-         operandLitValue (IC_LEFT (ic)) == 0.0)
-       {
-         ic->op = '=';
-         IC_LEFT (ic) = NULL;
-         SET_RESULT_RIGHT (ic);
-         return;
-       }
-      if (IS_OP_LITERAL (IC_RIGHT (ic)) &&
-         operandLitValue (IC_RIGHT (ic)) == 0.0)
+      if (IS_OP_LITERAL (IC_RIGHT (ic)))
        {
-         ic->op = '=';
-         IC_RIGHT (ic) = IC_LEFT (ic);
-         IC_LEFT (ic) = NULL;
-         SET_RESULT_RIGHT (ic);
-         return;
+         if (operandLitValue (IC_RIGHT (ic)) == 0.0)
+           {
+             ic->op = '=';
+             IC_RIGHT (ic) = IC_LEFT (ic);
+             IC_LEFT (ic) = NULL;
+             SET_RESULT_RIGHT (ic);
+             return;
+           }
        }
       break;
     }
@@ -1409,9 +1486,9 @@ deleteGetPointers (set ** cseSet, set ** pss, operand * op, eBBlock * ebb)
             list . This will take care of situations like
             iTemp1 = iTemp0 + 8;
             iTemp2 = iTemp1 + 8; */
-         if (isinSetWith (compItems, (void*)IC_LEFT (cdp->diCode), 
+         if (isinSetWith (compItems, (void*)IC_LEFT (cdp->diCode),
                           (insetwithFunc)isOperandEqual) ||
-             isinSetWith (compItems, (void*)IC_RIGHT (cdp->diCode), 
+             isinSetWith (compItems, (void*)IC_RIGHT (cdp->diCode),
                           (insetwithFunc)isOperandEqual))
            {
              addSet (&compItems, IC_RESULT (cdp->diCode));
@@ -1459,7 +1536,7 @@ DEFSETFUNC (delGetPointerSucc)
 /*-----------------------------------------------------------------*/
 /* fixUpTypes - KLUGE HACK fixup a lowering problem                */
 /*-----------------------------------------------------------------*/
-static void 
+static void
 fixUpTypes (iCode * ic)
 {
   sym_link *t1 = operandType (IC_LEFT (ic)), *t2;
@@ -1536,7 +1613,7 @@ static int isSignedOp (iCode *ic)
 /*             system. also the most important, since almost all   */
 /*             data flow related information is computed by it     */
 /*-----------------------------------------------------------------*/
-int 
+int
 cseBBlock (eBBlock * ebb, int computeOnly,
           eBBlock ** ebbs, int count)
 {
@@ -1670,7 +1747,7 @@ cseBBlock (eBBlock * ebb, int computeOnly,
 
       if (!computeOnly) {
        /* do some algebraic optimizations if possible */
-       algebraicOpts (ic);
+       algebraicOpts (ic, ebb);
        while (constFold (ic, cseSet));
       }
 
@@ -1781,7 +1858,7 @@ cseBBlock (eBBlock * ebb, int computeOnly,
       /* if left or right changed then do algebraic */
       if (!computeOnly && change)
        {
-         algebraicOpts (ic);
+         algebraicOpts (ic, ebb);
          while (constFold (ic, cseSet));
        }
 
@@ -1946,7 +2023,7 @@ cseBBlock (eBBlock * ebb, int computeOnly,
 /*-----------------------------------------------------------------*/
 /* cseAllBlocks - will sequentially go thru & do cse for all blocks */
 /*-----------------------------------------------------------------*/
-int 
+int
 cseAllBlocks (eBBlock ** ebbs, int count, int computeOnly)
 {
   int i;