From: Richard Guenther <rguenther@suse.de>
Date: Tue, 20 Apr 2010 13:09:42 +0000 (+0000)
Subject: re PR rtl-optimization/43438 (possible wrong code bug)
X-Git-Tag: releases/gcc-4.3.5~88
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b1a597aef307523a256c38f33f1d666fa59a9148;p=thirdparty%2Fgcc.git

re PR rtl-optimization/43438 (possible wrong code bug)

2010-04-20  Richard Guenther  <rguenther@suse.de>

	PR rtl-optimization/43438
	* combine.c (make_extraction): Properly zero-/sign-extend an
	extraction of the low part of a CONST_INT.

	* gcc.c-torture/execute/pr43438.c: New testcase.

From-SVN: r158555
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index c8d59b35b91c..794475166e07 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2010-04-20  Richard Guenther  <rguenther@suse.de>
+
+	PR rtl-optimization/43438
+	* combine.c (make_extraction): Properly zero-/sign-extend an
+	extraction of the low part of a CONST_INT.
+
 2010-04-20  Richard Guenther  <rguenther@suse.de>
 
 	PR tree-optimization/43629
diff --git a/gcc/combine.c b/gcc/combine.c
index 5d8239d0d9c0..49246d35f623 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -6552,7 +6552,8 @@ make_extraction (enum machine_mode mode, rtx inner, HOST_WIDE_INT pos,
 	return new;
 
       if (GET_CODE (new) == CONST_INT)
-	return gen_int_mode (INTVAL (new), mode);
+	return simplify_unary_operation (unsignedp ? ZERO_EXTEND : SIGN_EXTEND,
+					 mode, new, tmode);
 
       /* If we know that no extraneous bits are set, and that the high
 	 bit is not set, convert the extraction to the cheaper of
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index bbbee43d9860..45553b688a1a 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2010-04-20  Richard Guenther  <rguenther@suse.de>
+
+	PR rtl-optimization/43438
+	* gcc.c-torture/execute/pr43438.c: New testcase.
+
 2010-04-20  Richard Guenther  <rguenther@suse.de>
 
 	PR tree-optimization/43629
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr43438.c b/gcc/testsuite/gcc.c-torture/execute/pr43438.c
new file mode 100644
index 000000000000..aa901ce0f904
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr43438.c
@@ -0,0 +1,23 @@
+extern void abort (void);
+
+static unsigned char g_2 = 1;
+static int g_9;
+static int *l_8 = &g_9;
+
+static void func_12(int p_13)
+{
+  int * l_17 = &g_9;
+  *l_17 &= 0 < p_13;
+}
+
+int main(void)
+{
+  unsigned char l_11 = 254;
+  *l_8 |= g_2;
+  l_11 |= *l_8;
+  func_12(l_11);
+  if (g_9 != 1)
+    abort ();
+  return 0;
+} 
+