From: Kyrylo Tkachov <kyrylo.tkachov@arm.com>
Date: Mon, 14 Dec 2015 11:33:00 +0000 (+0000)
Subject: [combine] Don't create LSHIFTRT of zero bits in change_zero_ext
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=adb48173b8a6e7cba100e890c0ec60a9fb2188c6;p=gcc.git

[combine] Don't create LSHIFTRT of zero bits in change_zero_ext

	* combine.c (change_zero_ext): Do not create a shift of zero length.

From-SVN: r231613
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 6d3210f63c8..c79b65c9141 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2015-12-14  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
+
+	* combine.c (change_zero_ext): Do not create a shift of zero length.
+
 2015-12-14  Claudiu Zissulescu  <claziss@synopsys.com>
 
 	* config/arc/arc.c (TARGET_NO_SPECULATION_IN_DELAY_SLOTS_P):
diff --git a/gcc/combine.c b/gcc/combine.c
index 71b1656ba33..317a4b0e12a 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -11045,7 +11045,8 @@ change_zero_ext (rtx *src)
 	  if (BITS_BIG_ENDIAN)
 	    start = GET_MODE_PRECISION (mode) - size - start;
 
-	  x = gen_rtx_LSHIFTRT (mode, XEXP (x, 0), GEN_INT (start));
+	  x = simplify_gen_binary (LSHIFTRT, mode,
+				   XEXP (x, 0), GEN_INT (start));
 	}
       else if (GET_CODE (x) == ZERO_EXTEND
 	       && GET_CODE (XEXP (x, 0)) == SUBREG