From: DJ Delorie <dj@redhat.com>
Date: Sat, 30 May 2015 06:05:54 +0000 (-0400)
Subject: expmed.c (extract_bit_field_1): Avoid clobbering a yet-to-be-used base/index register.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=7d21a61eb5c0a7d12fa4b2bf2dfcb5ca7398a5bb;p=gcc.git

expmed.c (extract_bit_field_1): Avoid clobbering a yet-to-be-used base/index register.

* expmed.c (extract_bit_field_1): Avoid clobbering a
yet-to-be-used base/index register.

From-SVN: r223885
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 76992ee4a75..2f3fcaef242 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2015-05-28  DJ Delorie  <dj@redhat.com>
+
+	* expmed.c (extract_bit_field_1): Avoid clobbering a
+	yet-to-be-used base/index register.
+
 2015-05-30  Jan Hubicka  <hubicka@ucw.cz>
 
 	* alias.c (alias_set_entry_d): Add is_pointer and has_pointer.
diff --git a/gcc/expmed.c b/gcc/expmed.c
index fa13f8ced3f..4b2b02659e7 100644
--- a/gcc/expmed.c
+++ b/gcc/expmed.c
@@ -1616,6 +1616,11 @@ extract_bit_field_1 (rtx str_rtx, unsigned HOST_WIDE_INT bitsize,
       if (target == 0 || !REG_P (target) || !valid_multiword_target_p (target))
 	target = gen_reg_rtx (mode);
 
+      /* In case we're about to clobber a base register or something 
+	 (see gcc.c-torture/execute/20040625-1.c).   */
+      if (reg_mentioned_p (target, str_rtx))
+	target = gen_reg_rtx (mode);
+
       /* Indicate for flow that the entire target reg is being set.  */
       emit_clobber (target);