[PATCH 4/4] Write CodeView information about static locals in optimized code

[Mark Harmstone]

Write CodeView S_LDATA32 symbols for static locals in optimized code. We have
to handle these separately, as they come after the S_FRAMEPROC, plus you can't
have S_BLOCK32 symbols like you can in unoptimized code.

gcc/
        * dwarf2codeview.cc (write_optimized_static_local_vars): New function.
        (write_function): Call write_optimized_static_local_vars.
---
 gcc/dwarf2codeview.cc | 57 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)

diff --git a/gcc/dwarf2codeview.cc b/gcc/dwarf2codeview.cc
index 88310504cf7..e4c67f921cd 100644
--- a/gcc/dwarf2codeview.cc
+++ b/gcc/dwarf2codeview.cc
@@ -3007,6 +3007,62 @@ write_optimized_function_vars (dw_die_ref die, 
dw_loc_descr_ref fbloc,
   while (c != first_child);
 }
 
+/* There's no way to mark the range of a static local variable in an optimized
+   function: there's no S_DEFRANGE_* symbol for this, and you can't have
+   S_BLOCK32 symbols.  So instead we have to loop through after the S_FRAMEPROC
+   has been written, and write the S_LDATA32s at the end.  */
+
+static void
+write_optimized_static_local_vars (dw_die_ref die)
+{
+  dw_die_ref first_child, c;
+
+  first_child = dw_get_die_child (die);
+
+  if (!first_child)
+    return;
+
+  c = first_child;
+  do
+  {
+    c = dw_get_die_sib (c);
+
+    switch (dw_get_die_tag (c))
+      {
+      case DW_TAG_variable:
+       {
+         dw_attr_node *loc;
+         dw_loc_descr_ref loc_ref;
+
+         loc = get_AT (c, DW_AT_location);
+         if (!loc)
+           break;
+
+         if (loc->dw_attr_val.val_class != dw_val_class_loc)
+           break;
+
+         loc_ref = loc->dw_attr_val.v.val_loc;
+         if (!loc_ref)
+           break;
+
+         if (loc_ref->dw_loc_opc != DW_OP_addr)
+           break;
+
+         write_local_s_ldata32 (c, loc_ref);
+         break;
+       }
+
+      case DW_TAG_lexical_block:
+       write_optimized_static_local_vars (c);
+       break;
+
+      default:
+       break;
+      }
+  }
+  while (c != first_child);
+}
+
 /* Write an S_GPROC32_ID symbol, representing a global function, or an
    S_LPROC32_ID symbol, for a static function.  */
 
@@ -3143,6 +3199,7 @@ write_function (codeview_symbol *s)
       write_optimized_function_vars (s->function.die, fbloc, rtx_low,
                                     rtx_high);
       write_s_frameproc ();
+      write_optimized_static_local_vars (s->function.die);
     }
   else
     {
-- 
2.44.2