re PR debug/19124 (gcc generates incorrect dwarf2 debug info)

2005-01-20  Daniel Berlin  <dberlin@dberlin.org>

	Fix PR debug/19124
	* dwarf2out.c (concat_loc_descriptor): We don't know we can use
	fbreg, so we have to assume we can't.
	(loc_descriptor_from_tree_1): Ditto.
	(containing_function_has_frame_base): New function.
	(add_location_or_const_value_attribute): Use it.
	Also try to generate a frame_base from a single element location
	list.

From-SVN: r93979

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 53d41dbc2f4ba8b7bc188bee3c18b74a924d6809..cf511fa1dd8e4e23f46cea07baea3796b950065b 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,14 @@
+2005-01-20  Daniel Berlin  <dberlin@dberlin.org>
+
+       Fix PR debug/19124
+       * dwarf2out.c (concat_loc_descriptor): We don't know we can use
+       fbreg, so we have to assume we can't.
+       (loc_descriptor_from_tree_1): Ditto.
+       (containing_function_has_frame_base): New function.
+       (add_location_or_const_value_attribute): Use it.
+       Also try to generate a frame_base from a single element location
+       list.
+       
 2005-01-20  Kazu Hirata  <kazu@cs.umass.edu>
 
        PR tree-optimization/15349

diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index 76f67a5d0c6c01f187f48601aca2ae0e9a8b949f..6336cf69dba8b283d842e8f333af738ea4912f34 100644 (file)
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -8714,8 +8714,8 @@ static dw_loc_descr_ref
 concat_loc_descriptor (rtx x0, rtx x1)
 {
   dw_loc_descr_ref cc_loc_result = NULL;
-  dw_loc_descr_ref x0_ref = loc_descriptor (x0, true);
-  dw_loc_descr_ref x1_ref = loc_descriptor (x1, true);
+  dw_loc_descr_ref x0_ref = loc_descriptor (x0, false);
+  dw_loc_descr_ref x1_ref = loc_descriptor (x1, false);
 
   if (x0_ref == 0 || x1_ref == 0)
     return 0;
@@ -8934,7 +8934,7 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
 
            /* Certain constructs can only be represented at top-level.  */
            if (want_address == 2)
-             return loc_descriptor (rtl, true);
+             return loc_descriptor (rtl, false);
 
            mode = GET_MODE (rtl);
            if (MEM_P (rtl))
@@ -8942,7 +8942,7 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
                rtl = XEXP (rtl, 0);
                have_address = 1;
              }
-           ret = mem_loc_descriptor (rtl, mode, true);
+           ret = mem_loc_descriptor (rtl, mode, false);
          }
       }
       break;
@@ -9021,7 +9021,7 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
          return 0;
        mode = GET_MODE (rtl);
        rtl = XEXP (rtl, 0);
-       ret = mem_loc_descriptor (rtl, mode, true);
+       ret = mem_loc_descriptor (rtl, mode, false);
        have_address = 1;
        break;
       }
@@ -9971,6 +9971,29 @@ rtl_for_decl_location (tree decl)
   return rtl;
 }
 
+/* Return true if DECL's containing function has a frame base attribute.
+   Return false otherwise.  */
+
+static bool
+containing_function_has_frame_base (tree decl)
+{
+  tree declcontext = decl_function_context (decl);
+  dw_die_ref context;
+  dw_attr_ref attr;
+  
+  if (!declcontext)
+    return false;
+
+  context = lookup_decl_die (declcontext);
+  if (!context)
+    return false;
+
+  for (attr = context->die_attr; attr; attr = attr->dw_attr_next)
+    if (attr->dw_attr == DW_AT_frame_base)
+      return true;
+  return false;
+}
+  
 /* Generate *either* a DW_AT_location attribute or else a DW_AT_const_value
    data attribute for a variable or a parameter.  We generate the
    DW_AT_const_value attribute only in those cases where the given variable
@@ -9989,12 +10012,15 @@ add_location_or_const_value_attribute (dw_die_ref die, tree decl,
   rtx rtl;
   dw_loc_descr_ref descr;
   var_loc_list *loc_list;
-
+  bool can_use_fb;
+  struct var_loc_node *node;
   if (TREE_CODE (decl) == ERROR_MARK)
     return;
 
   gcc_assert (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == PARM_DECL
              || TREE_CODE (decl) == RESULT_DECL);
+            
+  can_use_fb = containing_function_has_frame_base (decl);
 
   /* See if we possibly have multiple locations for this variable.  */
   loc_list = lookup_decl_loc (decl);
@@ -10007,7 +10033,7 @@ add_location_or_const_value_attribute (dw_die_ref die, tree decl,
       const char *endname;
       dw_loc_list_ref list;
       rtx varloc;
-      struct var_loc_node *node;
+
 
       /* We need to figure out what section we should use as the base
         for the address ranges where a given location is valid.
@@ -10046,7 +10072,7 @@ add_location_or_const_value_attribute (dw_die_ref die, tree decl,
 
       node = loc_list->first;
       varloc = NOTE_VAR_LOCATION (node->var_loc_note);
-      list = new_loc_list (loc_descriptor (varloc, attr != DW_AT_frame_base),
+      list = new_loc_list (loc_descriptor (varloc, can_use_fb),
                           node->label, node->next->label, secname, 1);
       node = node->next;
 
@@ -10058,7 +10084,7 @@ add_location_or_const_value_attribute (dw_die_ref die, tree decl,
            varloc = NOTE_VAR_LOCATION (node->var_loc_note);
            add_loc_descr_to_loc_list (&list,
                                       loc_descriptor (varloc,
-                                                      attr != DW_AT_frame_base),
+                                                      can_use_fb),
                                       node->label, node->next->label, secname);
          }
 
@@ -10079,7 +10105,7 @@ add_location_or_const_value_attribute (dw_die_ref die, tree decl,
            }
          add_loc_descr_to_loc_list (&list,
                                     loc_descriptor (varloc,
-                                                    attr != DW_AT_frame_base),
+                                                    can_use_fb),
                                     node->label, endname, secname);
        }
 
@@ -10088,16 +10114,36 @@ add_location_or_const_value_attribute (dw_die_ref die, tree decl,
       return;
     }
 
+  /* Try to get some constant RTL for this decl, and use that as the value of
+     the location.  */
+  
   rtl = rtl_for_decl_location (decl);
   if (rtl && (CONSTANT_P (rtl) || GET_CODE (rtl) == CONST_STRING))
     {
       add_const_value_attribute (die, rtl);
       return;
     }
-
+  
+  /* We couldn't get any rtl, and we had no >1 element location list, so try
+     directly generating the location description from the tree.  */
   descr = loc_descriptor_from_tree (decl);
   if (descr)
-    add_AT_location_description (die, attr, descr);
+    {
+      add_AT_location_description (die, attr, descr);
+      return;
+    }
+  
+  /* Lastly, if we have tried to generate the location otherwise, and it
+     didn't work out (we wouldn't be here if we did), and we have a one entry
+     location list, try generating a location from that.  */
+  if (loc_list && loc_list->first)
+    {
+      node = loc_list->first;
+      descr = loc_descriptor (NOTE_VAR_LOCATION (node->var_loc_note), 
+                             can_use_fb);
+      if (descr)
+       add_AT_location_description (die, attr, descr);
+    }
 }
 
 /* If we don't have a copy of this variable in memory for some reason (such