From: Jakub Jelinek <jakub@redhat.com>
Date: Mon, 8 Jul 2013 08:17:35 +0000 (+0200)
Subject: re PR rtl-optimization/57829 (Wrong constant folding)
X-Git-Tag: releases/gcc-4.7.4~591
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8650444c174a14c38a72785576d56e45ddd78609;p=thirdparty%2Fgcc.git

re PR rtl-optimization/57829 (Wrong constant folding)

	PR rtl-optimization/57829
	* simplify-rtx.c (simplify_binary_operation_1) <case IOR>: Ensure that
	mask bits outside of mode are just sign-extension from mode to HWI.

	* gcc.c-torture/execute/pr57829.c: New test.

From-SVN: r200773
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 37b67a5215f2..a4b9337986fd 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2013-07-08  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/57829
+	* simplify-rtx.c (simplify_binary_operation_1) <case IOR>: Ensure that
+	mask bits outside of mode are just sign-extension from mode to HWI.
+
 2013-07-05  Uros Bizjak  <ubizjak@gmail.com>
 
 	Backport from mainline
diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c
index 550759af7e77..a0c4395f1138 100644
--- a/gcc/simplify-rtx.c
+++ b/gcc/simplify-rtx.c
@@ -2558,6 +2558,7 @@ simplify_binary_operation_1 (enum rtx_code code, enum machine_mode mode,
           HOST_WIDE_INT mask = INTVAL (trueop1) << count;
 
           if (mask >> count == INTVAL (trueop1)
+	      && trunc_int_for_mode (mask, mode) == mask
               && (mask & nonzero_bits (XEXP (op0, 0), mode)) == 0)
 	    return simplify_gen_binary (ASHIFTRT, mode,
 					plus_constant (XEXP (op0, 0), mask),
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 6fd55a6a3082..a0b8748770cb 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2013-07-08  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/57829
+	* gcc.c-torture/execute/pr57829.c: New test.
+
 2013-07-05  Uros Bizjak  <ubizjak@gmail.com>
 
 	Backport from mainline
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr57829.c b/gcc/testsuite/gcc.c-torture/execute/pr57829.c
new file mode 100644
index 000000000000..b5c3d185d0a9
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr57829.c
@@ -0,0 +1,31 @@
+/* PR rtl-optimization/57829 */
+
+__attribute__((noinline, noclone))
+int
+f1 (int k)
+{
+  return 2 | ((k - 1) >> ((int) sizeof (int) * __CHAR_BIT__ - 1));
+}
+
+__attribute__((noinline, noclone))
+long int
+f2 (long int k)
+{
+  return 2L | ((k - 1L) >> ((int) sizeof (long int) * __CHAR_BIT__ - 1));
+}
+
+__attribute__((noinline, noclone))
+int
+f3 (int k)
+{
+  k &= 63;
+  return 4 | ((k + 2) >> 5);
+}
+
+int
+main ()
+{
+  if (f1 (1) != 2 || f2 (1L) != 2L || f3 (63) != 6 || f3 (1) != 4)
+    __builtin_abort ();
+  return 0;
+}