2016-10-12 Richard Biener <rguenther@suse.de>

	* tree-ssa-propagate.c
	(substitute_and_fold_dom_walker::before_dom_children): Do not
	ignore ASSERT_EXPRs but only preserve them.
	* tree-vrp.c (remove_range_assertions): Deal with ASSERT_EXPRs
	that have been propagated into.
	(vrp_finalize): Enable DCE for substitute_and_fold.

	* gcc.dg/tree-ssa/vrp35.c: Adjust.
	* gcc.dg/tree-ssa/vrp36.c: Likewise.
	* gcc.dg/tree-ssa/vrp46.c: Likewise.

From-SVN: r241021

7 files changed, 33 insertions, 21 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 92a45d9..30c186a 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,14 @@
 2016-10-12  Richard Biener  <rguenther@suse.de>
 
+	* tree-ssa-propagate.c
+	(substitute_and_fold_dom_walker::before_dom_children): Do not
+	ignore ASSERT_EXPRs but only preserve them.
+	* tree-vrp.c (remove_range_assertions): Deal with ASSERT_EXPRs
+	that have been propagated into.
+	(vrp_finalize): Enable DCE for substitute_and_fold.
+
+2016-10-12  Richard Biener  <rguenther@suse.de>
+
 	PR tree-optimization/77920
 	* tree-vrp.c (simplify_div_or_mod_using_ranges): Simplify.
 	(simplify_min_or_max_using_ranges): Pass in gsi and use it.
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 1ebd9bd..1c4d4cf 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,11 @@
 2016-10-12  Richard Biener  <rguenther@suse.de>
 
+	* gcc.dg/tree-ssa/vrp35.c: Adjust.
+	* gcc.dg/tree-ssa/vrp36.c: Likewise.
+	* gcc.dg/tree-ssa/vrp46.c: Likewise.
+
+2016-10-12  Richard Biener  <rguenther@suse.de>
+
 	PR tree-optimization/77920
 	* gcc.dg/torture/pr77920.c: New testcase.
 
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/vrp35.c b/gcc/testsuite/gcc.dg/tree-ssa/vrp35.c
index 1cf310b..20112ea 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/vrp35.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/vrp35.c
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
-/* { dg-options "-O2 -fdump-tree-vrp1" } */
+/* { dg-options "-O2 -fdump-tree-vrp1-details" } */
 
 int test1(int i, int k)
 {
@@ -11,4 +11,4 @@ int test1(int i, int k)
   return 1;
 }
 
-/* { dg-final { scan-tree-dump "Folding predicate j_.* == 10 to 0" "vrp1" } } */
+/* { dg-final { scan-tree-dump "Removing dead stmt \[^\r\n\]* = j_.* == 10" "vrp1" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/vrp36.c b/gcc/testsuite/gcc.dg/tree-ssa/vrp36.c
index 873a7c9..3933254 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/vrp36.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/vrp36.c
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
-/* { dg-options "-O2 -fdump-tree-vrp1" } */
+/* { dg-options "-O2 -fdump-tree-vrp1-details" } */
 
 int foo(int i)
 {
@@ -8,4 +8,4 @@ int foo(int i)
   return 1;
 }
 
-/* { dg-final { scan-tree-dump "Folding predicate i_.* == 1 to 0" "vrp1" } } */
+/* { dg-final { scan-tree-dump "Removing dead stmt \[^\r\n\]* = i_.* == 1" "vrp1" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/vrp46.c b/gcc/testsuite/gcc.dg/tree-ssa/vrp46.c
index d3c9ed1..ebdc2e3 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/vrp46.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/vrp46.c
@@ -27,6 +27,6 @@ func_18 ( int t )
     }
 }
 
-/* There should be a single if left.  */
+/* There should be no if left.  */
 
-/* { dg-final { scan-tree-dump-times "if" 1 "vrp1" } } */
+/* { dg-final { scan-tree-dump-times "if" 0 "vrp1" } } */
diff --git a/gcc/tree-ssa-propagate.c b/gcc/tree-ssa-propagate.c
index cd1cbd2..0f940cc 100644
--- a/gcc/tree-ssa-propagate.c
+++ b/gcc/tree-ssa-propagate.c
@@ -1035,15 +1035,6 @@ substitute_and_fold_dom_walker::before_dom_children (basic_block bb)
     {
       bool did_replace;
       gimple *stmt = gsi_stmt (i);
-      enum gimple_code code = gimple_code (stmt);
-
-      /* Ignore ASSERT_EXPRs.  They are used by VRP to generate
-	 range information for names and they are discarded
-	 afterwards.  */
-
-      if (code == GIMPLE_ASSIGN
-	  && TREE_CODE (gimple_assign_rhs1 (stmt)) == ASSERT_EXPR)
-	continue;
 
       /* No point propagating into a stmt we have a value for we
          can propagate into all uses.  Mark it for removal instead.  */
@@ -1056,7 +1047,10 @@ substitute_and_fold_dom_walker::before_dom_children (basic_block bb)
 	      && sprime != lhs
 	      && may_propagate_copy (lhs, sprime)
 	      && !stmt_could_throw_p (stmt)
-	      && !gimple_has_side_effects (stmt))
+	      && !gimple_has_side_effects (stmt)
+	      /* We have to leave ASSERT_EXPRs around for jump-threading.  */
+	      && (!is_gimple_assign (stmt)
+		  || gimple_assign_rhs_code (stmt) != ASSERT_EXPR))
 	    {
 	      stmts_to_remove.safe_push (stmt);
 	      continue;
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index e46f7fc..8d5fa66 100644
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -6894,9 +6894,9 @@ remove_range_assertions (void)
 	    imm_use_iterator iter;
 
 	    var = ASSERT_EXPR_VAR (rhs);
-	    gcc_assert (TREE_CODE (var) == SSA_NAME);
 
-	    if (!POINTER_TYPE_P (TREE_TYPE (lhs))
+	    if (TREE_CODE (var) == SSA_NAME
+		&& !POINTER_TYPE_P (TREE_TYPE (lhs))
 		&& SSA_NAME_RANGE_INFO (lhs))
 	      {
 		if (is_unreachable == -1)
@@ -6928,8 +6928,11 @@ remove_range_assertions (void)
 
 	    /* Propagate the RHS into every use of the LHS.  */
 	    FOR_EACH_IMM_USE_STMT (use_stmt, iter, lhs)
-	      FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
-		SET_USE (use_p, var);
+	      {
+		FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
+		  SET_USE (use_p, var);
+		update_stmt (use_stmt);
+	      }
 
 	    /* And finally, remove the copy, it is not needed.  */
 	    gsi_remove (&si, true);
@@ -10611,7 +10614,7 @@ vrp_finalize (bool warn_array_bounds_p)
       }
 
   substitute_and_fold (op_with_constant_singleton_value_range,
-		       vrp_fold_stmt, false);
+		       vrp_fold_stmt, true);
 
   if (warn_array_bounds && warn_array_bounds_p)
     check_all_array_refs ();