re PR middle-end/18908 (Missed folding opportunities with bools)

2011-07-20  Richard Guenther  <rguenther@suse.de>

	PR middle-end/18908
	* tree.c (integer_all_onesp): Use TYPE_PRECISION, not mode precision.
	* tree-ssa-forwprop.c (simplify_bitwise_binary): Remove bogus
	ADDR_EXPR folding.  Canonicalize X ^ ~0 as ~X.

	* gcc.dg/tree-ssa/pr18908.c: New testcase.
	* gcc.dg/tree-ssa/bitwise-sink.c: Adjust.

From-SVN: r176508

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index de9172ad03974b7a278c8782f12ecbb6364ce6b2..6a9b143b96c78fb02883c77869ee27eeeb8c0665 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2011-07-20  Richard Guenther  <rguenther@suse.de>
+
+       PR middle-end/18908
+       * tree.c (integer_all_onesp): Use TYPE_PRECISION, not mode precision.
+       * tree-ssa-forwprop.c (simplify_bitwise_binary): Remove bogus
+       ADDR_EXPR folding.  Canonicalize X ^ ~0 as ~X.
+
 2011-07-20  Vladimir Makarov  <vmakarov@redhat.com>
 
        * config/frv/frv.c (frv_register_move_cost): Define explicitly

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 9138237f036dab1a05d11661eff85071b27e9e96..1e2bc1c07cdee10ef095e36cbf1aa946246486c6 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2011-07-20  Richard Guenther  <rguenther@suse.de>
+
+       PR middle-end/18908
+       * gcc.dg/tree-ssa/pr18908.c: New testcase.
+       * gcc.dg/tree-ssa/bitwise-sink.c: Adjust.
+
 2011-07-20  Chung-Lin Tang  <cltang@codesourcery.com>
 
        * gcc.target/arm/combine-movs.c: New.

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/bitwise-sink.c b/gcc/testsuite/gcc.dg/tree-ssa/bitwise-sink.c
index f44529995b7748ce014a88c426c3c4ebf600c938..1de04bc84317e18c3d4ca6d12509c5ad4c73bdb1 100644 (file)
--- a/gcc/testsuite/gcc.dg/tree-ssa/bitwise-sink.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/bitwise-sink.c
@@ -7,5 +7,5 @@ foo (_Bool x)
   return (x ^ 1);
 }
 
-/* { dg-final { scan-tree-dump-times "x\[^ \]* \\^ 1" 1 "optimized" } } */
+/* { dg-final { scan-tree-dump-times "~x" 1 "optimized" } } */
 /* { dg-final { cleanup-tree-dump "optimized" } } */

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr18908.c b/gcc/testsuite/gcc.dg/tree-ssa/pr18908.c
new file mode 100644 (file)
index 0000000..cfc92fe
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr18908.c
@@ -0,0 +1,9 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-forwprop1" } */
+
+_Bool f3(_Bool *p) { *p ^= 1; }
+
+/* We should be able to canonicalize the above to use bitwise not.  */
+/* { dg-final { scan-tree-dump "~D" "forwprop1" } } */
+/* { dg-final { scan-tree-dump-not "\\\^ 1" "forwprop1" } } */
+/* { dg-final { cleanup-tree-dump "forwprop1" } } */

diff --git a/gcc/tree-ssa-forwprop.c b/gcc/tree-ssa-forwprop.c
index 5a40f5e604ebce0334de4a2aa77981d69be52528..577609b20149a289a54b61fba316f6927b684868 100644 (file)
--- a/gcc/tree-ssa-forwprop.c
+++ b/gcc/tree-ssa-forwprop.c
@@ -1710,37 +1710,6 @@ simplify_bitwise_binary (gimple_stmt_iterator *gsi)
   tree def1_arg1, def2_arg1;
   enum tree_code def1_code, def2_code;
 
-  /* If the first argument is an SSA name that is itself a result of a
-     typecast of an ADDR_EXPR to an integer, feed the ADDR_EXPR to the
-     folder rather than the ssa name.  */
-  if (code == BIT_AND_EXPR
-      && TREE_CODE (arg2) == INTEGER_CST
-      && TREE_CODE (arg1) == SSA_NAME)
-    {
-      gimple def = SSA_NAME_DEF_STMT (arg1);
-      tree op = arg1;
-
-      /* ???  This looks bogus - the conversion could be truncating.  */
-      if (is_gimple_assign (def)
-         && CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (def))
-         && INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
-       {
-         tree opp = gimple_assign_rhs1 (def);
-         if (TREE_CODE (opp) == ADDR_EXPR)
-           op = opp;
-       }
-
-      res = fold_binary_loc (gimple_location (stmt),
-                            BIT_AND_EXPR, TREE_TYPE (gimple_assign_lhs (stmt)),
-                            op, arg2);
-      if (res && is_gimple_min_invariant (res))
-       {
-         gimple_assign_set_rhs_from_tree (gsi, res);
-         update_stmt (stmt);
-         return true;
-       }
-    }
-
   def1_code = TREE_CODE (arg1);
   def1_arg1 = arg1;
   if (TREE_CODE (arg1) == SSA_NAME)
@@ -1862,6 +1831,17 @@ simplify_bitwise_binary (gimple_stmt_iterator *gsi)
       return true;
     }
 
+  /* Canonicalize X ^ ~0 to ~X.  */
+  if (code == BIT_XOR_EXPR
+      && TREE_CODE (arg2) == INTEGER_CST
+      && integer_all_onesp (arg2))
+    {
+      gimple_assign_set_rhs_with_ops (gsi, BIT_NOT_EXPR, arg1, NULL_TREE);
+      gcc_assert (gsi_stmt (*gsi) == stmt);
+      update_stmt (stmt);
+      return true;
+    }
+
   /* Try simple folding for X op !X, and X op X.  */
   res = simplify_bitwise_binary_1 (code, TREE_TYPE (arg1), arg1, arg2);
   if (res != NULL_TREE)