gdb/

	Remove excessive DWARF expressions memory duplication.
	* dwarf2loc.c (per_cu_dwarf_call): Remove variable back_to and its use
	for block.data.
	(indirect_pieced_value): Remove variable result.  Remove variable
	back_to and its use for baton.data.
	(dwarf2_compile_expr_to_ax): Remove variable back_to and its use for
	block.data.
	* dwarf2read.c (dwarf2_fetch_die_location_block): Remove xmemdup.
	Update the function comment.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index fcb60b9..34e8eb0 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,15 @@
+2011-09-13  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
+       Remove excessive DWARF expressions memory duplication.
+       * dwarf2loc.c (per_cu_dwarf_call): Remove variable back_to and its use
+       for block.data.
+       (indirect_pieced_value): Remove variable result.  Remove variable
+       back_to and its use for baton.data.
+       (dwarf2_compile_expr_to_ax): Remove variable back_to and its use for
+       block.data.
+       * dwarf2read.c (dwarf2_fetch_die_location_block): Remove xmemdup.
+       Update the function comment.
+
 2011-09-13  Pedro Alves  <pedro@codesourcery.com>
 
        * inferior.h (ALL_INFERIORS): New.

diff --git a/gdb/dwarf2loc.c b/gdb/dwarf2loc.c
index 41891bb..12b4997 100644 (file)
--- a/gdb/dwarf2loc.c
+++ b/gdb/dwarf2loc.c
@@ -265,19 +265,14 @@ per_cu_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset,
                   void *baton)
 {
   struct dwarf2_locexpr_baton block;
-  struct cleanup *back_to;
 
   block = dwarf2_fetch_die_location_block (die_offset, per_cu,
                                           get_frame_pc, baton);
 
-  back_to = make_cleanup (xfree, (void *) block.data);
-
   /* DW_OP_call_ref is currently not supported.  */
   gdb_assert (block.per_cu == per_cu);
 
   dwarf_expr_eval (ctx, block.data, block.size);
-
-  do_cleanups (back_to);
 }
 
 /* Helper interface of per_cu_dwarf_call for dwarf2_evaluate_loc_desc.  */
@@ -969,9 +964,7 @@ indirect_pieced_value (struct value *value)
   struct dwarf2_locexpr_baton baton;
   int i, bit_offset, bit_length;
   struct dwarf_expr_piece *piece = NULL;
-  struct value *result;
   LONGEST byte_offset;
-  struct cleanup *back_to;
 
   type = check_typedef (value_type (value));
   if (TYPE_CODE (type) != TYPE_CODE_PTR)
@@ -1021,15 +1014,9 @@ indirect_pieced_value (struct value *value)
                                           get_frame_address_in_block_wrapper,
                                           frame);
 
-  back_to = make_cleanup (xfree, (void *) baton.data);
-
-  result = dwarf2_evaluate_loc_desc_full (TYPE_TARGET_TYPE (type), frame,
-                                         baton.data, baton.size, baton.per_cu,
-                                         piece->v.ptr.offset + byte_offset);
-
-  do_cleanups (back_to);
-
-  return result;
+  return dwarf2_evaluate_loc_desc_full (TYPE_TARGET_TYPE (type), frame,
+                                       baton.data, baton.size, baton.per_cu,
+                                       piece->v.ptr.offset + byte_offset);
 }
 
 static void *
@@ -2147,14 +2134,12 @@ dwarf2_compile_expr_to_ax (struct agent_expr *expr, struct axs_value *loc,
          {
            struct dwarf2_locexpr_baton block;
            int size = (op == DW_OP_call2 ? 2 : 4);
-           struct cleanup *back_to;
 
            uoffset = extract_unsigned_integer (op_ptr, size, byte_order);
            op_ptr += size;
 
            block = dwarf2_fetch_die_location_block (uoffset, per_cu,
                                                     get_ax_pc, expr);
-           back_to = make_cleanup (xfree, (void *) block.data);
 
            /* DW_OP_call_ref is currently not supported.  */
            gdb_assert (block.per_cu == per_cu);
@@ -2162,8 +2147,6 @@ dwarf2_compile_expr_to_ax (struct agent_expr *expr, struct axs_value *loc,
            dwarf2_compile_expr_to_ax (expr, loc, arch, addr_size,
                                       block.data, block.data + block.size,
                                       per_cu);
-
-           do_cleanups (back_to);
          }
          break;
 

diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 6b87d2a..fc6a4d5 100644 (file)
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -13854,9 +13854,9 @@ follow_die_ref (struct die_info *src_die, struct attribute *attr,
   return die;
 }
 
-/* Return DWARF block and its CU referenced by OFFSET at PER_CU.  Returned
-   value is intended for DW_OP_call*.  You must call xfree on returned
-   dwarf2_locexpr_baton->data.  */
+/* Return DWARF block referenced by DW_AT_location of DIE at OFFSET at PER_CU.
+   Returned value is intended for DW_OP_call*.  Returned
+   dwarf2_locexpr_baton->data has lifetime of PER_CU->OBJFILE.  */
 
 struct dwarf2_locexpr_baton
 dwarf2_fetch_die_location_block (unsigned int offset,
@@ -13912,9 +13912,6 @@ dwarf2_fetch_die_location_block (unsigned int offset,
     }
   retval.per_cu = cu->per_cu;
 
-  if (retval.data)
-    retval.data = xmemdup (retval.data, retval.size, retval.size);
-
   age_cached_comp_units ();
 
   return retval;