re PR tree-optimization/25680 (Store CCP does not understand REALPART_EXPR < COMPLEX_CST >)

2006-02-18  Andrew Pinski  <pinskia@physics.uc.edu>

        PR tree-opt/25680
        * tree-ssa-ccp.c (ccp_fold): Handle store CCP of REALPART_EXPR and
        IMAGPART_EXPR.
2006-02-18  Andrew Pinski  <pinskia@physics.uc.edu>

        PR tree-opt/25680
        * testsuite/gcc.dg/tree-ssa/complex-3.c: New test.

From-SVN: r111251

gcc/ChangeLog

+2006-02-18  Andrew Pinski  <pinskia@physics.uc.edu>
+
+	PR tree-opt/25680
+	* tree-ssa-ccp.c (ccp_fold): Handle store CCP of REALPART_EXPR and
+	IMAGPART_EXPR.
+
 2006-02-18  Diego Novillo  <dnovillo@redhat.com>
 
 	* tree-flow.h (struct var_ann_d): Rename field is_alias_tag to

gcc/testsuite/ChangeLog

 2006-02-18  Andrew Pinski  <pinskia@physics.uc.edu>
 
+        PR tree-opt/25680
+        * testsuite/gcc.dg/tree-ssa/complex-3.c: New test.
+
+2006-02-18  Andrew Pinski  <pinskia@physics.uc.edu>
+
 	* gcc.dg/tree-ssa/20031106-1.c: Fix the final scan of the
 	variable to take into account the variable name in the
 	function header.

gcc/testsuite/gcc.dg/tree-ssa/complex-3.c

 /* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+int g(_Complex int*);
+int f(void)
+{
+  _Complex int t = 0;
+  int i, j;
+ __real__ t += 2;
+ __imag__ t += 2;
+  return g(&t);
+}
+
+/* { dg-final { scan-tree-dump-times "__complex__" 0 "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
+
+/* { dg-do compile } */
 /* { dg-options "-O -fdump-tree-optimized" } */
 
 typedef _Complex float COMPLEX_FLOAT;

gcc/tree-ssa-ccp.c

@@ -855,11 +855,19 @@ ccp_fold (tree stmt)
       /* If the RHS is a memory load, see if the VUSEs associated with
 	 it are a valid constant for that memory load.  */
       prop_value_t *val = get_value_loaded_by (stmt, const_val);
-      if (val && val->mem_ref
-	  && operand_equal_p (val->mem_ref, rhs, 0))
-	return val->value;
-      else
-	return NULL_TREE;
+      if (val && val->mem_ref)
+	{
+	  if (operand_equal_p (val->mem_ref, rhs, 0))
+	    return val->value;
+
+	  /* If RHS is extracting REALPART_EXPR or IMAGPART_EXPR of a
+	     complex type with a known constant value, return it.  */
+	  if ((TREE_CODE (rhs) == REALPART_EXPR
+	       || TREE_CODE (rhs) == IMAGPART_EXPR)
+	      && operand_equal_p (val->mem_ref, TREE_OPERAND (rhs, 0), 0))
+	    return fold_build1 (TREE_CODE (rhs), TREE_TYPE (rhs), val->value);
+	}
+      return NULL_TREE;
     }
 
   /* Unary operators.  Note that we know the single operand must