From: Kyrylo Tkachov <kyrylo.tkachov@arm.com>
Date: Tue, 24 Nov 2015 14:27:51 +0000 (+0000)
Subject: [RTL-ree] PR rtl-optimization/68194: Restrict copy instruction in presence of conditi... 
X-Git-Tag: releases/gcc-4.9.4~493
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=770c3af64adc6484c2806737cad47f38bf69f0b8;p=thirdparty%2Fgcc.git

[RTL-ree] PR rtl-optimization/68194: Restrict copy instruction in presence of conditional moves

	Backport from mainline
	2015-11-24  Bernd Schmidt <bschmidt@redhat.com>
	            Kyrylo Tkachov  <kyrylo.tkachov@arm.com>

	PR rtl-optimization/68194
	PR rtl-optimization/68328
	PR rtl-optimization/68185
	* ree.c (combine_reaching_defs): Reject copy_needed case if
	copies_list is not empty.

	* gcc.c-torture/execute/pr68185.c: New test.
	* gcc.c-torture/execute/pr68328.c: Likewise.

From-SVN: r230813
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 33584acf3515..f6cab87bb7de 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,15 @@
+2015-11-24  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
+
+	Backport from mainline
+	2015-11-24  Bernd Schmidt <bschmidt@redhat.com>
+	            Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
+
+	PR rtl-optimization/68194
+	PR rtl-optimization/68328
+	PR rtl-optimization/68185
+	* ree.c (combine_reaching_defs): Reject copy_needed case if
+	copies_list is not empty.
+
 2015-11-23  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	Backport from mainline
diff --git a/gcc/ree.c b/gcc/ree.c
index 7d00d816d400..60af8eadeac1 100644
--- a/gcc/ree.c
+++ b/gcc/ree.c
@@ -783,6 +783,12 @@ combine_reaching_defs (ext_cand *cand, const_rtx set_pat, ext_state *state)
       if (state->defs_list.length () != 1)
 	return false;
 
+      /* We don't have the structure described above if there are
+	 conditional moves in between the def and the candidate,
+	 and we will not handle them correctly.  See PR68194.  */
+      if (state->copies_list.length () > 0)
+	return false;
+
       /* We require the candidate not already be modified.  It may,
 	 for example have been changed from a (sign_extend (reg))
 	 into (zero_extend (sign_extend (reg))).
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 08984f016cd0..04a458433e7c 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,14 @@
+2015-11-24  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
+
+	Backport from mainline
+	2015-11-24  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
+
+	PR rtl-optimization/68194
+	PR rtl-optimization/68328
+	PR rtl-optimization/68185
+	* gcc.c-torture/execute/pr68185.c: New test.
+	* gcc.c-torture/execute/pr68328.c: Likewise.
+
 2015-11-23  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	Backport from mainline
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr68185.c b/gcc/testsuite/gcc.c-torture/execute/pr68185.c
new file mode 100644
index 000000000000..826531bf71ba
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr68185.c
@@ -0,0 +1,29 @@
+int a, b, d = 1, e, f, o, u, w = 1, z;
+short c, q, t;
+
+int
+main ()
+{
+  char g;
+  for (; d; d--)
+    {
+      while (o)
+	for (; e;)
+	  {
+	    c = b;
+	    int h = o = z;
+	    for (; u;)
+	      for (; a;)
+		;
+	  }
+      if (t < 1)
+	g = w;
+      f = g;
+      g && (q = 1);
+    }
+
+  if (q != 1)
+    __builtin_abort ();
+
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr68328.c b/gcc/testsuite/gcc.c-torture/execute/pr68328.c
new file mode 100644
index 000000000000..edf244bb3563
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr68328.c
@@ -0,0 +1,44 @@
+int a, b, c = 1, d = 1, e;
+
+__attribute__ ((noinline, noclone))
+     int foo (void)
+{
+  asm volatile ("":::"memory");
+  return 4195552;
+}
+
+__attribute__ ((noinline, noclone))
+     void bar (int x, int y)
+{
+  asm volatile (""::"g" (x), "g" (y):"memory");
+  if (y == 0)
+    __builtin_abort ();
+}
+
+int
+baz (int x)
+{
+  char g, h;
+  int i, j;
+
+  foo ();
+  for (;;)
+    {
+      if (c)
+	h = d;
+      g = h < x ? h : 0;
+      i = (signed char) ((unsigned char) (g - 120) ^ 1);
+      j = i > 97;
+      if (a - j)
+	bar (0x123456, 0);
+      if (!b)
+	return e;
+    }
+}
+
+int
+main ()
+{
+  baz (2);
+  return 0;
+}