[gentoo-commits] gentoo commit in src/patchsets/gcc/4.9.0/gentoo: 94_all_pr60902-ffmpeg-miscompile.patch README.history

[Ryan Hill (rhill)]

rhill       14/05/04 18:56:03

  Modified:             README.history
  Added:                94_all_pr60902-ffmpeg-miscompile.patch
  Log:
  Add patch for PR60902.

Revision  Changes    Path
1.2                  src/patchsets/gcc/4.9.0/gentoo/README.history

file : http://sources.gentoo.org/viewvc.cgi/gentoo/src/patchsets/gcc/4.9.0/gentoo/README.history?rev=1.2&view=markup
plain: http://sources.gentoo.org/viewvc.cgi/gentoo/src/patchsets/gcc/4.9.0/gentoo/README.history?rev=1.2&content-type=text/plain
diff : http://sources.gentoo.org/viewvc.cgi/gentoo/src/patchsets/gcc/4.9.0/gentoo/README.history?r1=1.1&r2=1.2

Index: README.history
===================================================================
RCS file: /var/cvsroot/gentoo/src/patchsets/gcc/4.9.0/gentoo/README.history,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- README.history	1 May 2014 05:14:25 -0000	1.1
+++ README.history	4 May 2014 18:56:03 -0000	1.2
@@ -21,3 +21,4 @@
 	+ 74_all_gcc49_cloog-dl.patch
 	+ 90_all_pr55930-dependency-tracking.patch
 	+ 92_all_freebsd-pie.patch
+	+ 94_all_pr60902-ffmpeg-miscompile.patch



1.1                  src/patchsets/gcc/4.9.0/gentoo/94_all_pr60902-ffmpeg-miscompile.patch

file : http://sources.gentoo.org/viewvc.cgi/gentoo/src/patchsets/gcc/4.9.0/gentoo/94_all_pr60902-ffmpeg-miscompile.patch?rev=1.1&view=markup
plain: http://sources.gentoo.org/viewvc.cgi/gentoo/src/patchsets/gcc/4.9.0/gentoo/94_all_pr60902-ffmpeg-miscompile.patch?rev=1.1&content-type=text/plain

Index: 94_all_pr60902-ffmpeg-miscompile.patch
===================================================================
http://gcc.gnu.org/PR60902


--- a/gcc/tree-ssa-threadedge.c
+++ b/gcc/tree-ssa-threadedge.c
@@ -387,7 +387,34 @@ record_temporary_equivalences_from_stmts_at_dest (edge e,
           && (gimple_code (stmt) != GIMPLE_CALL
               || gimple_call_lhs (stmt) == NULL_TREE
               || TREE_CODE (gimple_call_lhs (stmt)) != SSA_NAME))
+	{
+	  /* STMT might still have DEFS and we need to invalidate any known
+	     equivalences for them.
+
+	     Consider if STMT is a GIMPLE_ASM with one or more outputs that
+	     feeds a conditional inside a loop.  We might derive an equivalence
+	     due to the conditional.  */
+	  tree op;
+	  ssa_op_iter iter;
+
+	  if (backedge_seen)
+	    FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_DEF)
+	      {
+		/* This call only invalidates equivalences created by
+		   PHI nodes.  This is by design to keep the cost of
+		   of invalidation reasonable.  */
+		invalidate_equivalences (op, stack, src_map, dst_map);
+
+		/* However, conditionals can imply values for real
+		   operands as well.  And those won't be recorded in the
+		   maps.  In fact, those equivalences may be recorded totally
+		   outside the threading code.  We can just create a new
+		   temporary NULL equivalence here.  */
+	        record_temporary_equivalence (op, NULL_TREE, stack);
+	      }
+
 	continue;
+	}
 
       /* The result of __builtin_object_size depends on all the arguments
 	 of a phi node. Temporarily using only one edge produces invalid
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr60902.c
@@ -0,0 +1,32 @@
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+extern void abort ();
+extern void exit (int);
+
+int x;
+
+foo()
+{
+  static int count;
+  count++;
+  if (count > 1)
+    abort ();
+}
+
+static inline int
+frob ()
+{
+  int a;
+  __asm__ ("mov %1, %0\n\t" : "=r" (a) : "m" (x));
+  x++;
+  return a;
+}
+
+int
+main ()
+{
+  int i;
+  for (i = 0; i < 10 && frob () == 0; i++)
+    foo();
+  exit (0);
+}