From: Eric Botcazou <ebotcazou@adacore.com>
Date: Fri, 1 Feb 2013 10:26:07 +0000 (+0000)
Subject: fold-const.c (make_range_step): Bail out if the range isn't testing for zero.
X-Git-Tag: releases/gcc-4.6.4~166
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=71ae3542386c133734697c093710d6f61b4ffb0b;p=thirdparty%2Fgcc.git

fold-const.c (make_range_step): Bail out if the range isn't testing for zero.

	* fold-const.c (make_range_step) <TRUTH_NOT_EXPR>: Bail out if the
	range isn't testing for zero.

From-SVN: r195644
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b9cbffc5cd0f..45e913cf2475 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2013-02-01  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* fold-const.c (make_range_step) <TRUTH_NOT_EXPR>: Bail out if the
+	range isn't testing for zero.
+
 2013-01-27  Uros Bizjak  <ubizjak@gmail.com>
 
 	Backport from mainline
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index f11ddf14b75f..49f5e34c1b23 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -3873,6 +3873,10 @@ make_range (tree exp, int *pin_p, tree *plow, tree *phigh,
       switch (code)
 	{
 	case TRUTH_NOT_EXPR:
+	  /* We can only do something if the range is testing for zero.  */
+	  if (low == NULL_TREE || high == NULL_TREE
+	      || ! integer_zerop (low) || ! integer_zerop (high))
+	    break;
 	  in_p = ! in_p, exp = arg0;
 	  continue;
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 3b56128e1461..8c32bae9cf49 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2013-02-01  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gnat.dg/opt26.adb: New test.
+
 2013-01-24  Martin Jambor  <mjambor@suse.cz>
 
 	Backport from mainline
diff --git a/gcc/testsuite/gnat.dg/opt26.adb b/gcc/testsuite/gnat.dg/opt26.adb
new file mode 100644
index 000000000000..61f8b5b1eb99
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/opt26.adb
@@ -0,0 +1,37 @@
+-- { dg-do run }
+-- { dg-options "-gnato -O" }
+
+with Interfaces; use Interfaces;
+
+procedure Opt26 is
+
+   procedure Shift_Left_Bool
+     (Bool : in Boolean;
+      U8 : out Interfaces.Unsigned_8)
+   is
+   begin
+      U8 := Shift_Left (Boolean'Pos (Bool), 6);
+   end Shift_Left_Bool;
+
+   procedure Shift_Left_Not_Bool
+     (Bool : in Boolean;
+      U8 : out Interfaces.Unsigned_8)
+   is
+   begin
+      U8 := Shift_Left (Boolean'Pos (not Bool), 6);
+   end Shift_Left_Not_Bool;
+
+   Bool         : constant Boolean := True;
+   Byte1, Byte2 : Interfaces.Unsigned_8;
+
+begin
+
+   Shift_Left_Bool (Bool, Byte1);
+
+   Shift_Left_Not_Bool (Bool, Byte2);
+
+   if Byte1 + Byte2 /= 64 then
+     raise Program_Error;
+   end if;
+
+end;