re PR tree-optimization/26421 (tree-ssa-alias.c:find_used_portions considers…

re PR tree-optimization/26421 (tree-ssa-alias.c:find_used_portions considers foo(&var) use all elements of var)

2006-02-26  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/26421
	* tree-ssa-alias.c (find_used_portions): Don't treat parameters
	in function calls that are ADDR_EXPRs as using the whole structure.

	* gcc.dg/tree-ssa/pr26421.c: New testcase.

From-SVN: r111461

gcc/ChangeLog

+2006-02-26  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/26421
+	* tree-ssa-alias.c (find_used_portions): Don't treat parameters
+	in function calls that are ADDR_EXPRs as using the whole structure.
+
 2006-02-26  Steven Bosscher  <stevenb.gcc@gmail.com>
 
 	* common.opt (-floop-optimize, -frerun-loop-opt): Remove.

gcc/testsuite/ChangeLog

+2006-02-26  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/26421
+	* gcc.dg/tree-ssa/pr26421.c: New testcase.
+
 2006-02-26  Steven Bosscher  <stevenb.gcc@gmail.com>
 
 	* gcc.dg/20031201-1.c: Don't use -frerun-loop-opt.

gcc/testsuite/gcc.dg/tree-ssa/pr26421.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-alias1-vops" } */
+
+typedef struct {
+  int i;
+  int j;
+  int k;
+} Foo;
+
+void bar(Foo*);
+void foo(void)
+{
+  Foo a;
+  a.i = 1;
+  bar(&a);
+}
+
+/* { dg-final { scan-tree-dump-times "V_MAY_DEF" 1 "alias1" } } */
+/* { dg-final { cleanup-tree-dump "alias1" } } */

gcc/tree-ssa-alias.c

@@ -3078,6 +3078,17 @@ find_used_portions (tree *tp, int *walk_subtrees, void *lhs_p)
 	  }
       }
       break;
+    case CALL_EXPR:
+      {
+	tree *arg;
+	for (arg = &TREE_OPERAND (*tp, 1); *arg; arg = &TREE_CHAIN (*arg))
+	  {
+	    if (TREE_CODE (TREE_VALUE (*arg)) != ADDR_EXPR)
+              find_used_portions (&TREE_VALUE (*arg), walk_subtrees, NULL);
+	  }
+	*walk_subtrees = 0;
+	return NULL_TREE;
+      }
     case VAR_DECL:
     case PARM_DECL:
     case RESULT_DECL: