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[PR,tree-optimization/69270] Exploit VRP information in DOM

Message ID 56985E33.40600@redhat.com
State New
Headers show

Commit Message

Jeff Law Jan. 15, 2016, 2:49 a.m. UTC 
On 01/14/2016 11:27 AM, Jeff Law wrote:
>
>> Apart from what Jakub said we have constant_boolean_node for this,
>>
>>    true_val = constant_boolean_node (true, TREE_TYPE (op0));
> Will update.  Thanks.
Here's the patch which uses constant_boolean_node and verifies the type 
is unsigned when it has a single bit of precision case.

The other part of Jakub's suggestion regresses code generation in the 
final assembly -- we're getting some constant initializations when 
they're not needed.  I'm highly confident we just need to mirror a few 
bits into the uncprop pass, which I'll be looking at directly.

Bootstrapped and regression tested on x86_64.  Installed on the trunk.

Jeff
commit d1bdc38e96ec5ae607a472968134e5d8b0ac4456
Author: law <law@138bc75d-0d04-0410-961f-82ee72b054a4>
Date:   Fri Jan 15 02:45:44 2016 +0000

           PR tree-optimization/69270
            * tree-ssa-dom.c (ssa_name_has_boolean_range): If the type has a
            single bit of precision, verify it's also unsigned.
            (record_edge_info): Use constant_boolean_node rather than fold_convert
            to convert boolean_true/boolean_false to the right type.
    
    git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@232399 138bc75d-0d04-0410-961f-82ee72b054a4
diff mbox

Patch

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 790662511..6f9c6a5 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@ 
+2016-01-14  Jeff Law  <law@redhat.com>
+
+	PR tree-optimization/69270
+	* tree-ssa-dom.c (ssa_name_has_boolean_range): If the type has a
+	single bit of precision, verify it's also unsigned.
+	(record_edge_info): Use constant_boolean_node rather than fold_convert
+	to convert boolean_true/boolean_false to the right type.
+
 2016-01-14  Richard Henderson  <rth@redhat.com>
 
 	PR rtl-opt/69014
diff --git a/gcc/tree-ssa-dom.c b/gcc/tree-ssa-dom.c
index da4faca..f2257b3 100644
--- a/gcc/tree-ssa-dom.c
+++ b/gcc/tree-ssa-dom.c
@@ -319,8 +319,8 @@  record_conditions (struct edge_info *edge_info, tree cond, tree inverted)
 /* Return TRUE is OP, an SSA_NAME has a range of values [0..1], false
    otherwise.
 
-   This can be because it is a boolean type, any type with
-   a single bit of precision, or has known range of [0..1]
+   This can be because it is a boolean type, any unsigned integral
+   type with a single bit of precision, or has known range of [0..1]
    via VRP analysis.  */
 
 static bool
@@ -332,6 +332,7 @@  ssa_name_has_boolean_range (tree op)
 
   /* An integral type with a single bit of precision.  */
   if (INTEGRAL_TYPE_P (TREE_TYPE (op))
+      && TYPE_UNSIGNED (TREE_TYPE (op))
       && TYPE_PRECISION (TREE_TYPE (op)) == 1)
     return true;
 
@@ -425,10 +426,9 @@  record_edge_info (basic_block bb)
 	      && ssa_name_has_boolean_range (op0)
               && is_gimple_min_invariant (op1))
             {
-	      tree true_val = fold_convert (TREE_TYPE (op0),
-					    boolean_true_node);
-	      tree false_val = fold_convert (TREE_TYPE (op0),
-					     boolean_false_node);
+	      tree true_val = constant_boolean_node (true, TREE_TYPE (op0));
+	      tree false_val = constant_boolean_node (false, TREE_TYPE (op0));
+
               if (code == EQ_EXPR)
                 {
                   edge_info = allocate_edge_info (true_edge);