re PR debug/47991 (Var-tracking ICE on s390x *setmem_long insn)

PR debug/47991
	* var-tracking.c (find_use_val): Return NULL for
	cui->sets && cui->store_p BLKmode MEMs.

	* gcc.dg/pr47991.c: New test.

From-SVN: r170759

gcc/ChangeLog

@@ -1,3 +1,9 @@
+2011-03-07  Jakub Jelinek  <jakub@redhat.com>
+
+	PR debug/47991
+	* var-tracking.c (find_use_val): Return NULL for
+	cui->sets && cui->store_p BLKmode MEMs.
+
 2011-03-07  Anatoly Sokolov  <aesok@post.ru>
 
 	* config/stormy16/stormy16.h (PRINT_OPERAND, PRINT_OPERAND_ADDRESS):

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2011-03-07  Jakub Jelinek  <jakub@redhat.com>
+
+	PR debug/47991
+	* gcc.dg/pr47991.c: New test.
+
 2011-03-07  Jason Merrill  <jason@redhat.com>
 
 	* g++.dg/abi/mangle46.C: New.

gcc/testsuite/gcc.dg/pr47991.c

@@ -0,0 +1,25 @@
+/* PR debug/47991 */
+/* { dg-do compile } */
+/* { dg-options "-g -Os" } */
+
+typedef __SIZE_TYPE__ size_t;
+extern inline __attribute__ ((__always_inline__))
+void *
+memset (void *x, int y, size_t z)
+{
+  return __builtin___memset_chk (x, y, z, __builtin_object_size (x, 0));
+}
+
+void
+foo (unsigned char *x, unsigned char *y, unsigned char *z,
+     unsigned char *w, unsigned int v, int u, int t)
+{
+  int i;
+  for (i = 0; i < t; i++)
+    {
+      memset (z, x[0], v);
+      memset (w, y[0], v);
+      x += u;
+    }
+  __builtin_memcpy (z, x, u);
+}

gcc/var-tracking.c

@@ -1,5 +1,5 @@
 /* Variable tracking routines for the GNU compiler.
-   Copyright (C) 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010
+   Copyright (C) 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011
    Free Software Foundation, Inc.
 
    This file is part of GCC.
@@ -4790,6 +4790,13 @@ find_use_val (rtx x, enum machine_mode mode, struct count_use_info *cui)
 	 stores.  */
       if (cui->store_p)
 	{
+	  /* Some targets represent memset and memcpy patterns
+	     by (set (mem:BLK ...) (reg:[QHSD]I ...)) or
+	     (set (mem:BLK ...) (const_int ...)) or
+	     (set (mem:BLK ...) (mem:BLK ...)).  Don't return anything
+	     in that case, otherwise we end up with mode mismatches.  */
+	  if (mode == BLKmode && MEM_P (x))
+	    return NULL;
 	  for (i = 0; i < cui->n_sets; i++)
 	    if (cui->sets[i].dest == x)
 	      return cui->sets[i].src_elt;