From: Tom de Vries <tom@codesourcery.com>
Date: Mon, 6 Aug 2012 08:32:20 +0000 (+0000)
Subject: tree-switch-conversion.c (emit_case_bit_tests): Generate MINUS_EXPR in unsigned type.
X-Git-Tag: releases/gcc-4.8.0~4105
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d9e408ded1129fa823d55137eb1cb2c1a9979adb;p=thirdparty%2Fgcc.git

tree-switch-conversion.c (emit_case_bit_tests): Generate MINUS_EXPR in unsigned type.

2012-08-06  Tom de Vries  <tom@codesourcery.com>

	* tree-switch-conversion.c (emit_case_bit_tests): Generate MINUS_EXPR in
	unsigned type.

From-SVN: r190168
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e228bfb2c6dc..2169ca5627e0 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2012-08-06  Tom de Vries  <tom@codesourcery.com>
+
+	* tree-switch-conversion.c (emit_case_bit_tests): Generate MINUS_EXPR in
+	unsigned type.
+
 2012-08-05  Venkataramanan Kumar  <venkataramanan.kumar@amd.com>
 
 	* doc/invoke.texi: Document AMD btver2.
diff --git a/gcc/tree-switch-conversion.c b/gcc/tree-switch-conversion.c
index 0630f1a5b933..6c61eca3b612 100644
--- a/gcc/tree-switch-conversion.c
+++ b/gcc/tree-switch-conversion.c
@@ -384,10 +384,10 @@ emit_case_bit_tests (gimple swtch, tree index_expr,
 
   gsi = gsi_last_bb (switch_bb);
 
-  /* idx = (unsigned) (x - minval) */
-  idx = fold_build2 (MINUS_EXPR, index_type, index_expr,
-		     fold_convert (index_type, minval));
-  idx = fold_convert (unsigned_index_type, idx);
+  /* idx = (unsigned)x - minval.  */
+  idx = fold_convert (unsigned_index_type, index_expr);
+  idx = fold_build2 (MINUS_EXPR, unsigned_index_type, idx,
+		     fold_convert (unsigned_index_type, minval));
   idx = force_gimple_operand_gsi (&gsi, idx,
 				  /*simple=*/true, NULL_TREE,
 				  /*before=*/true, GSI_SAME_STMT);