tree-ssa-pre.c (eliminate_dom_walker::before_dom_children): Rewrite to propagate…

tree-ssa-pre.c (eliminate_dom_walker::before_dom_children): Rewrite to propagate the VN result into all uses where possible and to remove...

2014-06-13  Richard Biener  <rguenther@suse.de>

	* tree-ssa-pre.c (eliminate_dom_walker::before_dom_children):
	Rewrite to propagate the VN result into all uses where
	possible and to remove stmts becoming dead because of that.
	(eliminate): Generalize stmt removal handling, remove in
	reverse dominator order to support proper debug stmt
	generation.  Update stmts before removing stmts.
	* tree-ssa-propagate.c (propagate_tree_value): Remove
	bogus assert.

	* c-c++-common/pr46562-2.c: Adjust.
	* g++.dg/tree-ssa/pr8781.C: Likewise.
	* gcc.dg/tree-ssa/ssa-fre-24.c: Likewise.
	* gcc.dg/tree-ssa/ssa-fre-25.c: Likewise.
	* gcc.dg/tree-ssa/ssa-fre-32.c: Likewise.
	* gcc.dg/tree-ssa/ssa-fre-39.c: Likewise.
	* gcc.dg/tree-ssa/ssa-pre-16.c: Likewise.

From-SVN: r211625

gcc/ChangeLog

+2014-06-13  Richard Biener  <rguenther@suse.de>
+
+	* tree-ssa-pre.c (eliminate_dom_walker::before_dom_children):
+	Rewrite to propagate the VN result into all uses where
+	possible and to remove stmts becoming dead because of that.
+	(eliminate): Generalize stmt removal handling, remove in
+	reverse dominator order to support proper debug stmt
+	generation.  Update stmts before removing stmts.
+	* tree-ssa-propagate.c (propagate_tree_value): Remove
+	bogus assert.
+
 2014-06-13  Thomas Preud'homme  <thomas.preudhomme@arm.com>
 
 	PR tree-optimization/61375

gcc/testsuite/ChangeLog

+2014-06-13  Richard Biener  <rguenther@suse.de>
+
+	* c-c++-common/pr46562-2.c: Adjust.
+	* g++.dg/tree-ssa/pr8781.C: Likewise.
+	* gcc.dg/tree-ssa/ssa-fre-24.c: Likewise.
+	* gcc.dg/tree-ssa/ssa-fre-25.c: Likewise.
+	* gcc.dg/tree-ssa/ssa-fre-32.c: Likewise.
+	* gcc.dg/tree-ssa/ssa-fre-39.c: Likewise.
+	* gcc.dg/tree-ssa/ssa-pre-16.c: Likewise.
+
 2014-06-13  Thomas Preud'homme  <thomas.preudhomme@arm.com>
 
 	PR tree-optimization/61375

gcc/testsuite/c-c++-common/pr46562-2.c

@@ -9,5 +9,5 @@ int foo(void)
   return *p;
 }
 
-/* { dg-final { scan-tree-dump "= 0;" "fre1" } } */
+/* { dg-final { scan-tree-dump "return 0;" "fre1" } } */
 /* { dg-final { cleanup-tree-dump "fre1" } } */

gcc/testsuite/g++.dg/tree-ssa/pr8781.C

 /* { dg-do compile } */
-/* { dg-options "-O -fno-tree-sra -fdump-tree-fre1-details" } */
+/* { dg-options "-O -fno-tree-sra -fdump-tree-fre1" } */
 
 int f();
 
@@ -24,5 +24,5 @@ int x()
 
 /* We should optimize this to a direct call.  */
 
-/* { dg-final { scan-tree-dump "converting indirect call to function int f()" "fre1" } } */
+/* { dg-final { scan-tree-dump-times "= f \\(\\);" 1 "fre1" } } */
 /* { dg-final { cleanup-tree-dump "fre1" } } */

gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-24.c

@@ -30,5 +30,5 @@ int bazzoo (void)
   return b.i;
 }
 
-/* { dg-final { scan-tree-dump-times "= 0;" 5 "fre1" } } */
+/* { dg-final { scan-tree-dump-times "return 0;" 4 "fre1" } } */
 /* { dg-final { cleanup-tree-dump "fre1" } } */

gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-25.c

@@ -14,5 +14,5 @@ int foo (struct X *p)
 
 /* We should optimize this to return 0.  */
 
-/* { dg-final { scan-tree-dump "= 0;" "fre1" } } */
+/* { dg-final { scan-tree-dump "return 0;" "fre1" } } */
 /* { dg-final { cleanup-tree-dump "fre1" } } */

gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-32.c

@@ -23,6 +23,6 @@ bar (_Complex float x)
   return z;
 } 
 
-/* We should CSE all the way to replace the final assignment to z with x.  */
-/* { dg-final { scan-tree-dump-times "with x_1\\\(D\\\) in z" 3 "fre1" } } */
+/* We should CSE all the way to replace the return value with x.  */
+/* { dg-final { scan-tree-dump-times "return x_\\d\+\\(D\\);" 2 "fre1" } } */
 /* { dg-final { cleanup-tree-dump "fre1" } } */

gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-39.c

@@ -15,5 +15,5 @@ int foo (int i)
 
 /* We should be able to value-number the final assignment to k to 1.  */
 
-/* { dg-final { scan-tree-dump "k_. = 1;" "fre1" } } */
+/* { dg-final { scan-tree-dump "return 1;" "fre1" } } */
 /* { dg-final { cleanup-tree-dump "fre1" } } */

gcc/testsuite/gcc.dg/tree-ssa/ssa-pre-16.c

@@ -11,5 +11,5 @@ int foo(int k, int *x)
   }  while (++j<k);
   return res;
 }
-/* { dg-final { scan-tree-dump-times "Eliminated: 1" 1 "pre"} } */
+/* { dg-final { scan-tree-dump-times "Eliminated: 2" 1 "pre"} } */
 /* { dg-final { cleanup-tree-dump "pre" } } */

gcc/tree-ssa-propagate.c

@@ -1410,11 +1410,6 @@ replace_exp (use_operand_p op_p, tree val)
 void
 propagate_tree_value (tree *op_p, tree val)
 {
-  gcc_checking_assert (!(TREE_CODE (val) == SSA_NAME
-			 && *op_p
-			 && TREE_CODE (*op_p) == SSA_NAME
-			 && !may_propagate_copy (*op_p, val)));
-
   if (TREE_CODE (val) == SSA_NAME)
     *op_p = val;
   else