re PR tree-optimization/21658 (CCP does not propagate ADDR_EXPR far enough.)

gcc/
	PR tree-optimization/21658
	* tree-ssa-ccp.c (ccp_fold): Call fold_binary instead of
	fold_binary_to_constant.  Likewise, call fold_unary instead of
	fold_unary_to_constant.

testsuite/
	PR tree-optimization/21658
	* gcc.dg/tree-ssa/pr21658.c: New.

From-SVN: r100266

gcc/ChangeLog

+2005-05-27  Kazu Hirata  <kazu@cs.umass.edu>
+
+	PR tree-optimization/21658
+	* tree-ssa-ccp.c (ccp_fold): Call fold_binary instead of
+	fold_binary_to_constant.  Likewise, call fold_unary instead of
+	fold_unary_to_constant.
+
 2005-05-27  Nathan Sidwell  <nathan@codesourcery.com>
 
 	* vec.h: Implement integral type vector specialization.

gcc/testsuite/ChangeLog

+2005-05-27  Kazu Hirata  <kazu@cs.umass.edu>
+
+	PR tree-optimization/21658
+	* gcc.dg/tree-ssa/pr21658.c: New.
+
 2005-05-27  Nathan Sidwell  <nathan@codesourcery.com>
 
 	PR c++/21455

gcc/testsuite/gcc.dg/tree-ssa/pr21658.c

+/* PR tree-optimization/21658
+   CCP did not propagate an ADDR_EXPR far enough, preventing the "if"
+   statement below from being folded.  */
+
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-tree-dominator-opts -fdump-tree-ccp-details" } */
+
+void link_error (void);
+
+void
+f (void)
+{
+  int a[10];
+  int *p = &a[5];
+  int *q = p - 1;
+  if (q != &a[4])
+    link_error ();
+}
+
+/* { dg-final { scan-tree-dump-times "with if \\(0\\)" 1 "ccp"} } */
+/* { dg-final { cleanup-tree-dump "ccp" } } */

gcc/tree-ssa-ccp.c

@@ -849,7 +849,7 @@ ccp_fold (tree stmt)
 	    op0 = get_value (op0, true)->value;
 	}
 
-      retval = fold_unary_to_constant (code, TREE_TYPE (rhs), op0);
+      retval = fold_unary (code, TREE_TYPE (rhs), op0);
 
       /* If we folded, but did not create an invariant, then we can not
 	 use this expression.  */
@@ -900,7 +900,7 @@ ccp_fold (tree stmt)
 	    op1 = val->value;
 	}
 
-      retval = fold_binary_to_constant (code, TREE_TYPE (rhs), op0, op1);
+      retval = fold_binary (code, TREE_TYPE (rhs), op0, op1);
 
       /* If we folded, but did not create an invariant, then we can not
 	 use this expression.  */