From 5e601bc28e283511b3f5d1bb1d2904251d909563 Mon Sep 17 00:00:00 2001
From: Mark Wielaard <mjw@redhat.com>
Date: Fri, 27 Apr 2012 14:27:14 +0200
Subject: [PATCH] dwarf2out.c: For DWARF 4+, output DW_AT_high_pc as constant
 offset.

        * dwarf2out.h (enum dw_val_class): Add dw_val_class_high_pc.
        * dwarf2out.c (dw_val_equal_p): Handle dw_val_class_high_pc.
        (add_AT_low_high_pc): New function.
        (AT_lbl): Handle dw_val_class_high_pc.
        (print_die): Likewise.
        (attr_checksum): Likewise.
        (attr_checksum_ordered): Likewise.
        (same_dw_val_p): Likewise.
        (size_of_die): Likewise.
        (value_format): Likewise.
        (output_die): Likewise.
        (gen_subprogram_die): Use add_AT_low_high_pc.
        (add_high_low_attributes): Likewise.
        (dwarf2out_finish): Likewise.
---
 gcc/ChangeLog   |   17 +++++++++++
 gcc/dwarf2out.c |   87 +++++++++++++++++++++++++++++++++++++++----------------
 gcc/dwarf2out.h |    3 +-
 3 files changed, 81 insertions(+), 26 deletions(-)

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a93d3cd..66a32ad 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,20 @@
+2012-04-27  Mark Wielaard  <mjw@redhat.com>
+
+	* dwarf2out.h (enum dw_val_class): Add dw_val_class_high_pc.
+	* dwarf2out.c (dw_val_equal_p): Handle dw_val_class_high_pc.
+	(add_AT_low_high_pc): New function.
+	(AT_lbl): Handle dw_val_class_high_pc.
+	(print_die): Likewise.
+	(attr_checksum): Likewise.
+	(attr_checksum_ordered): Likewise.
+	(same_dw_val_p): Likewise.
+	(size_of_die): Likewise.
+	(value_format): Likewise.
+	(output_die): Likewise.
+	(gen_subprogram_die): Use add_AT_low_high_pc.
+	(add_high_low_attributes): Likewise.
+	(dwarf2out_finish): Likewise.
+
 2012-04-25  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/53110
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index 766edba..fa2963b 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -1647,6 +1647,7 @@ dw_val_equal_p (dw_val_node *a, dw_val_node *b)
     case dw_val_class_fde_ref:
       return a->v.val_fde_index == b->v.val_fde_index;
     case dw_val_class_lbl_id:
+    case dw_val_class_high_pc:
       return strcmp (a->v.val_lbl_id, b->v.val_lbl_id) == 0;
     case dw_val_class_str:
       return a->v.val_str == b->v.val_str;
@@ -4350,6 +4351,26 @@ add_AT_data8 (dw_die_ref die, enum dwarf_attribute attr_kind,
   add_dwarf_attr (die, &attr);
 }
 
+/* Add DW_AT_low_pc and DW_AT_high_pc to a DIE.  */
+static inline void
+add_AT_low_high_pc (dw_die_ref die, const char *lbl_low, const char *lbl_high)
+{
+  dw_attr_node attr;
+
+  attr.dw_attr = DW_AT_low_pc;
+  attr.dw_attr_val.val_class = dw_val_class_lbl_id;
+  attr.dw_attr_val.v.val_lbl_id = xstrdup (lbl_low);
+  add_dwarf_attr (die, &attr);
+
+  attr.dw_attr = DW_AT_high_pc;
+  if (dwarf_version < 3)
+    attr.dw_attr_val.val_class = dw_val_class_lbl_id;
+  else
+    attr.dw_attr_val.val_class = dw_val_class_high_pc;
+  attr.dw_attr_val.v.val_lbl_id = xstrdup (lbl_high);
+  add_dwarf_attr (die, &attr);
+}
+
 /* Hash and equality functions for debug_str_hash.  */
 
 static hashval_t
@@ -4723,7 +4744,8 @@ AT_lbl (dw_attr_ref a)
 {
   gcc_assert (a && (AT_class (a) == dw_val_class_lbl_id
 		    || AT_class (a) == dw_val_class_lineptr
-		    || AT_class (a) == dw_val_class_macptr));
+		    || AT_class (a) == dw_val_class_macptr
+		    || AT_class (a) == dw_val_class_high_pc));
   return a->dw_attr_val.v.val_lbl_id;
 }
 
@@ -5602,6 +5624,7 @@ print_die (dw_die_ref die, FILE *outfile)
 	case dw_val_class_lbl_id:
 	case dw_val_class_lineptr:
 	case dw_val_class_macptr:
+	case dw_val_class_high_pc:
 	  fprintf (outfile, "label: %s", AT_lbl (a));
 	  break;
 	case dw_val_class_str:
@@ -5758,6 +5781,7 @@ attr_checksum (dw_attr_ref at, struct md5_ctx *ctx, int *mark)
     case dw_val_class_lbl_id:
     case dw_val_class_lineptr:
     case dw_val_class_macptr:
+    case dw_val_class_high_pc:
       break;
 
     case dw_val_class_file:
@@ -6030,6 +6054,7 @@ attr_checksum_ordered (enum dwarf_tag tag, dw_attr_ref at,
     case dw_val_class_lbl_id:
     case dw_val_class_lineptr:
     case dw_val_class_macptr:
+    case dw_val_class_high_pc:
       break;
 
     case dw_val_class_file:
@@ -6489,6 +6514,7 @@ same_dw_val_p (const dw_val_node *v1, const dw_val_node *v2, int *mark)
     case dw_val_class_lbl_id:
     case dw_val_class_lineptr:
     case dw_val_class_macptr:
+    case dw_val_class_high_pc:
       return 1;
 
     case dw_val_class_file:
@@ -7780,6 +7806,9 @@ size_of_die (dw_die_ref die)
 	case dw_val_class_vms_delta:
 	  size += DWARF_OFFSET_SIZE;
 	  break;
+	case dw_val_class_high_pc:
+	  size += DWARF2_ADDR_SIZE;
+	  break;
 	default:
 	  gcc_unreachable ();
 	}
@@ -8097,6 +8126,17 @@ value_format (dw_attr_ref a)
     case dw_val_class_data8:
       return DW_FORM_data8;
 
+    case dw_val_class_high_pc:
+      switch (DWARF2_ADDR_SIZE)
+	{
+	  case 4:
+	    return DW_FORM_data4;
+	  case 8:
+	    return DW_FORM_data8;
+	  default:
+	    gcc_unreachable ();
+	}
+
     default:
       gcc_unreachable ();
     }
@@ -8521,6 +8561,11 @@ output_die (dw_die_ref die)
 	    break;
 	  }
 
+	case dw_val_class_high_pc:
+	  dw2_asm_output_delta (DWARF2_ADDR_SIZE, AT_lbl (a),
+				get_AT_low_pc (die), "DW_AT_high_pc");
+	  break;
+
 	default:
 	  gcc_unreachable ();
 	}
@@ -17310,19 +17355,18 @@ gen_subprogram_die (tree decl, dw_die_ref context_die)
 	  if (fde->dw_fde_begin)
 	    {
 	      /* We have already generated the labels.  */
-	      add_AT_lbl_id (subr_die, DW_AT_low_pc, fde->dw_fde_begin);
-	      add_AT_lbl_id (subr_die, DW_AT_high_pc, fde->dw_fde_end);
+	      add_AT_low_high_pc (subr_die, fde->dw_fde_begin, fde->dw_fde_end);
 	    }
 	  else
 	    {
 	      /* Create start/end labels and add the range.  */
-	      char label_id[MAX_ARTIFICIAL_LABEL_BYTES];
-	      ASM_GENERATE_INTERNAL_LABEL (label_id, FUNC_BEGIN_LABEL,
+	      char label_id_low[MAX_ARTIFICIAL_LABEL_BYTES];
+	      char label_id_high[MAX_ARTIFICIAL_LABEL_BYTES];
+	      ASM_GENERATE_INTERNAL_LABEL (label_id_low, FUNC_BEGIN_LABEL,
 					   current_function_funcdef_no);
-	      add_AT_lbl_id (subr_die, DW_AT_low_pc, label_id);
-	      ASM_GENERATE_INTERNAL_LABEL (label_id, FUNC_END_LABEL,
+	      ASM_GENERATE_INTERNAL_LABEL (label_id_high, FUNC_END_LABEL,
 					   current_function_funcdef_no);
-	      add_AT_lbl_id (subr_die, DW_AT_high_pc, label_id);
+	      add_AT_low_high_pc (subr_die, label_id_low, label_id_high);
 	    }
 
 #if VMS_DEBUGGING_INFO
@@ -17388,10 +17432,8 @@ gen_subprogram_die (tree decl, dw_die_ref context_die)
 		  dw_die_ref seg_die;
 
 		  /* Do the 'primary' section.   */
-		  add_AT_lbl_id (subr_die, DW_AT_low_pc,
-				 fde->dw_fde_begin);
-		  add_AT_lbl_id (subr_die, DW_AT_high_pc,
-				 fde->dw_fde_end);
+		  add_AT_low_high_pc (subr_die, fde->dw_fde_begin,
+				      fde->dw_fde_end);
 		  /* Add it.   */
 		  add_pubname (decl, subr_die);
 
@@ -17417,18 +17459,15 @@ gen_subprogram_die (tree decl, dw_die_ref context_die)
 		    add_AT_flag (seg_die, DW_AT_artificial, 1);
 
 		  name = concat ("__second_sect_of_", name, NULL); 
-		  add_AT_lbl_id (seg_die, DW_AT_low_pc,
-				 fde->dw_fde_second_begin);
-		  add_AT_lbl_id (seg_die, DW_AT_high_pc,
-				 fde->dw_fde_second_end);
+		  add_AT_low_high_pc (seg_die, fde->dw_fde_second_begin,
+				      fde->dw_fde_second_end);
 		  add_name_attribute (seg_die, name);
 		  add_pubname_string (name, seg_die);
 		}
 	    }
 	  else
 	    {
-	      add_AT_lbl_id (subr_die, DW_AT_low_pc, fde->dw_fde_begin);
-	      add_AT_lbl_id (subr_die, DW_AT_high_pc, fde->dw_fde_end);
+	      add_AT_low_high_pc (subr_die, fde->dw_fde_begin, fde->dw_fde_end);
 	      add_pubname (decl, subr_die);
 	    }
 	}
@@ -18166,12 +18205,12 @@ add_high_low_attributes (tree stmt, dw_die_ref die)
     }
   else
     {
+      char label_high[MAX_ARTIFICIAL_LABEL_BYTES];
       ASM_GENERATE_INTERNAL_LABEL (label, BLOCK_BEGIN_LABEL,
 				   BLOCK_NUMBER (stmt));
-      add_AT_lbl_id (die, DW_AT_low_pc, label);
-      ASM_GENERATE_INTERNAL_LABEL (label, BLOCK_END_LABEL,
+      ASM_GENERATE_INTERNAL_LABEL (label_high, BLOCK_END_LABEL,
 				   BLOCK_NUMBER (stmt));
-      add_AT_lbl_id (die, DW_AT_high_pc, label);
+      add_AT_low_high_pc (die, label, label_high);
     }
 }
 
@@ -22635,10 +22674,8 @@ dwarf2out_finish (const char *filename)
     {
       /* Don't add if the CU has no associated code.  */
       if (text_section_used)
-	{
-	  add_AT_lbl_id (comp_unit_die (), DW_AT_low_pc, text_section_label);
-	  add_AT_lbl_id (comp_unit_die (), DW_AT_high_pc, text_end_label);
-	}
+	add_AT_low_high_pc (comp_unit_die (), text_section_label,
+			    text_end_label);
     }
   else
     {
diff --git a/gcc/dwarf2out.h b/gcc/dwarf2out.h
index 711e8ab..da3a578 100644
--- a/gcc/dwarf2out.h
+++ b/gcc/dwarf2out.h
@@ -154,7 +154,8 @@ enum dw_val_class
   dw_val_class_file,
   dw_val_class_data8,
   dw_val_class_decl_ref,
-  dw_val_class_vms_delta
+  dw_val_class_vms_delta,
+  dw_val_class_high_pc
 };
 
 /* Describe a floating point constant value, or a vector constant value.  */
-- 
1.7.7.6

