File gcc41-ppc32-retaddr.patch of Package gcc7.21370
2005-11-28 Jakub Jelinek <jakub@redhat.com>
* config/rs6000/rs6000.c (rs6000_return_addr): If COUNT == 0,
read word RETURN_ADDRESS_OFFSET bytes above arg_pointer_rtx
instead of doing an extran indirection from frame_pointer_rtx.
* gcc.dg/20051128-1.c: New test.
#Index: gcc/config/rs6000/rs6000.c
#===================================================================
#--- gcc/config/rs6000/rs6000.c.orig 2013-11-26 15:42:33.000000000 +0100
#+++ gcc/config/rs6000/rs6000.c 2013-11-26 16:44:14.566089231 +0100
#@@ -20878,18 +20878,22 @@ rs6000_return_addr (int count, rtx frame
if (count != 0
|| ((DEFAULT_ABI == ABI_V4 || DEFAULT_ABI == ABI_DARWIN) && flag_pic))
{
+ rtx x;
cfun->machine->ra_needs_full_frame = 1;
- return
- gen_rtx_MEM
- (Pmode,
- memory_address
- (Pmode,
- plus_constant (Pmode,
- copy_to_reg
- (gen_rtx_MEM (Pmode,
- memory_address (Pmode, frame))),
- RETURN_ADDRESS_OFFSET)));
+ if (count == 0)
+ {
+ gcc_assert (frame == frame_pointer_rtx);
+ x = arg_pointer_rtx;
+ }
+ else
+ {
+ x = memory_address (Pmode, frame);
+ x = copy_to_reg (gen_rtx_MEM (Pmode, x));
+ }
+
+ x = plus_constant (Pmode, x, RETURN_ADDRESS_OFFSET);
+ return gen_rtx_MEM (Pmode, memory_address (Pmode, x));
}
cfun->machine->ra_need_lr = 1;
Index: gcc/testsuite/gcc.dg/20051128-1.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ gcc/testsuite/gcc.dg/20051128-1.c 2013-11-26 16:44:14.566089231 +0100
@@ -0,0 +1,41 @@
+/* { dg-do run } */
+/* { dg-options "-O2 -fpic" } */
+
+extern void exit (int);
+extern void abort (void);
+
+int b;
+
+struct A
+{
+ void *pad[147];
+ void *ra, *h;
+ long o;
+};
+
+void
+__attribute__((noinline))
+foo (struct A *a, void *x)
+{
+ __builtin_memset (a, 0, sizeof (a));
+ if (!b)
+ exit (0);
+}
+
+void
+__attribute__((noinline))
+bar (void)
+{
+ struct A a;
+
+ __builtin_unwind_init ();
+ foo (&a, __builtin_return_address (0));
+}
+
+int
+main (void)
+{
+ bar ();
+ abort ();
+ return 0;
+}