Do not instrument register variables in object-size sanitizer (PR sanitizer/70878).

2017-04-11  Martin Liska  <mliska@suse.cz>

	PR sanitizer/70878
	* ubsan.c (instrument_object_size): Do not instrument register
	variables.
2017-04-11  Martin Liska  <mliska@suse.cz>

	PR sanitizer/70878
	* gcc.dg/ubsan/pr70878.c: New test.

From-SVN: r246837

gcc/ChangeLog

+2017-04-11  Martin Liska  <mliska@suse.cz>
+
+	PR sanitizer/70878
+	* ubsan.c (instrument_object_size): Do not instrument register
+	variables.
+
 2017-04-11  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/80381

gcc/testsuite/ChangeLog

+2017-04-11  Martin Liska  <mliska@suse.cz>
+
+	PR sanitizer/70878
+	* gcc.dg/ubsan/pr70878.c: New test.
+
 2017-04-11  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/80381

gcc/testsuite/gcc.dg/ubsan/pr70878.c

+/* PR sanitizer/80878 */
+/* { dg-do compile { target { { i?86-*-* x86_64-*-* } && lp64 } } } */
+/* { dg-options "-fsanitize=object-size" } */
+
+void * sbrk ()
+{
+ volatile register unsigned int sp_r1 __asm__ ("ebx");
+ return __builtin_strcat ((char*)sp_r1, 0); /* { dg-warning "cast to pointer from integer of different size" } */
+}

gcc/ubsan.c

@@ -1806,7 +1806,11 @@ instrument_object_size (gimple_stmt_iterator *gsi, bool is_lhs)
   bool decl_p = DECL_P (inner);
   tree base;
   if (decl_p)
+    {
+      if (DECL_REGISTER (inner))
+	return;
       base = inner;
+    }
   else if (TREE_CODE (inner) == MEM_REF)
     base = TREE_OPERAND (inner, 0);
   else