[PATCH][committed] Fix FRAME_RELATED_P marker for rx port

[Jeff Law]

Another maybe_record_trace_start issue found by my tester.  This time
the rx port.

We failed to add suitable notes for the CFI machinery.  There's still
paths (particularly those which save/restore the accumulators) that may
need further adjustment.  However, this patch is enough to get
libgcc/newlib building.

Tested by verifying that rx-elf will successfully build libgcc and newlib.

Installing on the trunk.

Jeff

        * config/rx/rx.c (add_pop_cfi_notes): New function.;
        (pop_regs): Use it.

diff --git a/gcc/config/rx/rx.c b/gcc/config/rx/rx.c
index be8229818a..c3845a8f6d 100644
--- a/gcc/config/rx/rx.c
+++ b/gcc/config/rx/rx.c
@@ -1644,6 +1644,20 @@ mark_frame_related (rtx insn)
     }
 }
 
+/* Create CFI notes for register pops.  */
+static void
+add_pop_cfi_notes (rtx_insn *insn, unsigned int high, unsigned int low)
+{
+  rtx t = plus_constant (Pmode, stack_pointer_rtx,
+                        (high - low + 1) * UNITS_PER_WORD);
+  t = gen_rtx_SET (stack_pointer_rtx, t);
+  add_reg_note (insn, REG_CFA_ADJUST_CFA, t);
+  RTX_FRAME_RELATED_P (insn) = 1;
+  for (unsigned int i = low; i <= high; i++)
+    add_reg_note (insn, REG_CFA_RESTORE, gen_rtx_REG (word_mode, i));
+}
+
+
 static bool
 ok_for_max_constant (HOST_WIDE_INT val)
 {
@@ -2029,11 +2044,14 @@ rx_can_use_simple_return (void)
 static void
 pop_regs (unsigned int high, unsigned int low)
 {
+  rtx_insn *insn;
   if (high == low)
-    emit_insn (gen_stack_pop (gen_rtx_REG (SImode, low)));
+    insn = emit_insn (gen_stack_pop (gen_rtx_REG (SImode, low)));
   else
-    emit_insn (gen_stack_popm (GEN_INT (((high - low) + 1) * UNITS_PER_WORD),
-                              gen_rx_popm_vector (low, high)));
+    insn = emit_insn (gen_stack_popm (GEN_INT (((high - low) + 1)
+                                               * UNITS_PER_WORD),
+                                     gen_rx_popm_vector (low, high)));
+  add_pop_cfi_notes (insn, high, low);
 }
 
 void