S/390: PR79904: Disallow reg + sym_ref literal pool addresses.

We accept reg + sym_ref as valid address if sym_ref is a literal pool
reference knowing that it will be rewritten as r13 + reg + offset.
However, annotate_constant_pool_refs was never able to handle that.

With the patch only single sym_refs are accepted.

Regression tested on s390x.

2017-03-24  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	PR target/79904
	* config/s390/s390.c (s390_decompose_address): Reject reg +
	sym_ref literal pool references.

gcc/testsuite/ChangeLog:

2017-03-24  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	* gcc.dg/ubsan/pr79904-2.c: New test.

From-SVN: r246443

gcc/config/s390/s390.c

@@ -2842,13 +2842,10 @@ s390_decompose_address (rtx addr, struct s390_address *out)
      displacements by basing them off the base register.  */
   if (disp && GET_CODE (disp) == SYMBOL_REF && CONSTANT_POOL_ADDRESS_P (disp))
     {
-      /* Either base or index must be free to hold the base register.  */
-      if (!base)
-        base = fake_pool_base, literal_pool = true;
-      else if (!indx)
-        indx = fake_pool_base, literal_pool = true;
-      else
-        return false;
+      if (base || indx)
+	return false;
+
+      base = fake_pool_base, literal_pool = true;
 
       /* Mark up the displacement.  */
       disp = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, disp),

gcc/testsuite/ChangeLog

 2017-03-24  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
 
+	* gcc.dg/ubsan/pr79904-2.c: New test.
+
+2017-03-24  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
+
 	PR target/79893
 	* gcc.target/s390/zvector/pr79893.c: New test.
 

gcc/testsuite/gcc.dg/ubsan/pr79904-2.c

+/* PR sanitizer/79904 */
+/* { dg-do compile } */
+/* { dg-options "-fsanitize=signed-integer-overflow" } */
+
+typedef signed char V __attribute__((vector_size (8))); 
+
+void
+foo (V *a) 
+{ 
+  *a = *a * (V) { 3, 4, 5, 6, 7, 8, 9, 10 }; 
+}