From: Sergey Ostanevich <sergos.gnu@gmail.com>
Date: Mon, 7 Nov 2011 08:41:55 +0000 (+0000)
Subject: re PR rtl-optimization/47698 (CMOV accessing volatile memory with read side effect)
X-Git-Tag: releases/gcc-4.7.0~2418
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b3242a4c75342dc2a5260fd452b9ea5c9d604296;p=thirdparty%2Fgcc.git

re PR rtl-optimization/47698 (CMOV accessing volatile memory with read side effect)

gcc/
	PR rtl-optimization/47698
	* ifconv.c (noce_operand_ok): prevent CMOV generation
	for volatile mem.

gcc/testsuite/
	PR rtl-optimization/47698
	* gcc.target/i386/47698.c: New test.

From-SVN: r181075
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f8f33d90a821..95809a3a0293 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2011-11-07  Sergey Ostanevich  <sergos.gnu@gmail.com>
+
+	PR rtl-optimization/47698
+	* ifconv.c (noce_operand_ok): prevent CMOV generation
+	for volatile mem.
+
 2011-11-07  Tristan Gingold  <gingold@adacore.com>
 
 	* common/config/alpha/alpha-common.c (alpha_option_init_struct):
diff --git a/gcc/ifcvt.c b/gcc/ifcvt.c
index 784e2e8b106b..3b05c2a8ad87 100644
--- a/gcc/ifcvt.c
+++ b/gcc/ifcvt.c
@@ -2329,12 +2329,12 @@ noce_operand_ok (const_rtx op)
 {
   /* We special-case memories, so handle any of them with
      no address side effects.  */
-  if (MEM_P (op))
-    return ! side_effects_p (XEXP (op, 0));
-
   if (side_effects_p (op))
     return FALSE;
 
+  if (MEM_P (op))
+    return ! side_effects_p (XEXP (op, 0));
+
   return ! may_trap_p (op);
 }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 1f9aa8103030..7e7209c1d63e 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+
+2011-11-07  Sergey Ostanevich  <sergos.gnu@gmail.com>
+
+	PR rtl-optimization/47698
+	* gcc.target/i386/47698.c: New test.
+
 2011-11-06  Jason Merrill  <jason@redhat.com>
 
 	PR c++/35688
diff --git a/gcc/testsuite/gcc.target/i386/47698.c b/gcc/testsuite/gcc.target/i386/47698.c
new file mode 100644
index 000000000000..2c751093ae37
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/47698.c
@@ -0,0 +1,10 @@
+/* { dg-options "-Os" } */
+/* { dg-final { scan-assembler-not "cmov" } } */
+
+extern volatile unsigned long mmio;
+unsigned long foo(int cond)
+{
+      if (cond)
+              return mmio;
+        return 0;
+}