From patchwork Tue Aug 24 19:19:26 2010
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Subject: Avoid creating invalid gimple in eliminate_redundant_comparison (PR
 tree-optimization/45059)
Date: Tue, 24 Aug 2010 09:19:26 -0000
From: Jakub Jelinek <jakub@redhat.com>
X-Patchwork-Id: 62620
Message-Id: <20100824191926.GS702@tyan-ft48-01.lab.bos.redhat.com>
To: gcc-patches@gcc.gnu.org

Hi!

In some cases the operands of the comparison won't have the desired type,
e.g. if there were any (useless) differences in types of the operands.
Having a NOP_EXPR as gimple comparison's operand is invalid though.

Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux.
Ok for trunk?

2010-08-24  Jakub Jelinek  <jakub@redhat.com>

	PR tree-optimization/45059
	* tree-ssa-reassoc.c (eliminate_redundant_comparison): Strip useless
	type conversions from newop{1,2}.  Assert t is a comparison and
	newop{1,2} after the stripping are gimple vals.

	* gcc.c-torture/compile/pr45059.c: New test.


	Jakub


--- gcc/tree-ssa-reassoc.c.jj	2010-08-20 16:05:41.000000000 +0200
+++ gcc/tree-ssa-reassoc.c	2010-08-24 19:16:57.000000000 +0200
@@ -1314,9 +1314,14 @@ eliminate_redundant_comparison (enum tre
 	  enum tree_code subcode;
 	  tree newop1;
 	  tree newop2;
+	  gcc_assert (COMPARISON_CLASS_P (t));
 	  tmpvar = create_tmp_var (TREE_TYPE (t), NULL);
 	  add_referenced_var (tmpvar);
 	  extract_ops_from_tree (t, &subcode, &newop1, &newop2);
+	  STRIP_USELESS_TYPE_CONVERSION (newop1);
+	  STRIP_USELESS_TYPE_CONVERSION (newop2);
+	  gcc_checking_assert (is_gimple_val (newop1)
+			       && is_gimple_val (newop2));
 	  sum = build_and_add_sum (tmpvar, newop1, newop2, subcode);
 	  curr->op = gimple_get_lhs (sum);
 	}
--- gcc/testsuite/gcc.c-torture/compile/pr45059.c.jj	2010-08-24 19:05:44.000000000 +0200
+++ gcc/testsuite/gcc.c-torture/compile/pr45059.c	2010-08-24 19:05:25.000000000 +0200
@@ -0,0 +1,23 @@
+/* PR tree-optimization/45059 */
+
+typedef unsigned int T;
+extern void foo (signed char *, int);
+
+static signed char a;
+static T b[1] = { -1 };
+static unsigned char c;
+
+static inline short int
+bar (short v)
+{
+  c |= a < b[0];
+  return 0;
+}
+
+int
+main ()
+{
+  signed char *e = &a;
+  foo (e, bar (bar (c)));
+  return 0;
+}