From: Vladimir Makarov <vmakarov@redhat.com>
Date: Mon, 15 Dec 2014 20:04:04 +0000 (+0000)
Subject: re PR target/62642 (x86 rdtsc is moved through barrier)
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=d8c1674416836c4b4573172b541992ddd12df713;p=gcc.git

re PR target/62642 (x86 rdtsc is moved through barrier)

2014-12-15  Vladimir Makarov  <vmakarov@redhat.com>

	PR target/62642
	* ira.c (rtx_moveable_p): Prevent UNSPEC_VOLATILE moves.

From-SVN: r218761
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 8276d646c5d..87ee0f9f475 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,9 +1,14 @@
+2014-12-15  Vladimir Makarov  <vmakarov@redhat.com>
+
+	PR target/62642
+	* ira.c (rtx_moveable_p): Prevent UNSPEC_VOLATILE moves.
+
 2014-12-15  Vladimir Makarov  <vmakarov@redhat.com>
 
 	* ira-int.h (ira_prohibited_class_mode_regs): Remove.
 	(struct target_ira_int): Move x_ira_prohibited_class_mode_regs to
 	...
-	* ira.h (struct target_ira_int): ... here.
+	* ira.h (struct target_ira): ... here.
 	(ira_prohibited_class_mode_regs): Define.
 	* lra-constraints.c (process_alt_operands): Add one more condition
 	to refuse alternative when reload pseudo of given class can not
diff --git a/gcc/ira.c b/gcc/ira.c
index e610d358177..f08aa23e408 100644
--- a/gcc/ira.c
+++ b/gcc/ira.c
@@ -4358,6 +4358,12 @@ rtx_moveable_p (rtx *loc, enum op_type type)
     case CLOBBER:
       return rtx_moveable_p (&SET_DEST (x), OP_OUT);
 
+    case UNSPEC_VOLATILE:
+      /* It is a bad idea to consider insns with with such rtl
+	 as moveable ones.  The insn scheduler also considers them as barrier
+	 for a reason.  */
+      return false;
+
     default:
       break;
     }