readelf: print actual DIE offsets of DW_OP_GNU_<type> ops.

Like DW_OP_GNU_parameter_ref the DW_OP_GNU type conversion ops
DW_OP_GNU_const_type, DW_OP_GNU_regval_type, DW_OP_GNU_deref_type,
DW_OP_GNU_convert and DW_OP_GNU_reinterpret take a CU relative offset
to a DIE (in these cases a DW_TAG_base_type). So handle the DIE offsets
just like in the DW_OP_GNU_parameter_ref case by adding the cu->start
if known (and -U hasn't been given). For DW_OP_GNU_convert and
DW_OP_GNU_reinterpret handle zero specially since it means to "untype"
the result and so isn't an actual DIE reference.

Signed-off-by: Mark Wielaard <mjw@redhat.com>

diff --git a/src/readelf.c b/src/readelf.c
index d6208cbde7577692fa75aa4abdb806b7fbe4f507..119c10003644dcd070b998cc7c0d8e1871025bfc 100644 (file)
--- a/src/readelf.c
+++ b/src/readelf.c
@@ -4042,10 +4042,13 @@ print_ops (Dwfl_Module *dwflmod, Dwarf *dbg, int indent, int indentrest,
          break;
 
        case DW_OP_GNU_const_type:
-         /* DIE offset, size plus block.  */
+         /* uleb128 CU relative DW_TAG_base_type DIE offset, 1-byte
+            unsigned size plus block.  */
          start = data;
          NEED (2);
          get_uleb128 (uleb, data); /* XXX check overrun */
+         if (! print_unresolved_addresses && cu != NULL)
+           uleb += cu->start;
          uint8_t usize = *(uint8_t *) data++;
          NEED (usize);
          printf ("%*s[%4" PRIuMAX "] %s [%6" PRIxMAX "] ",
@@ -4057,21 +4060,29 @@ print_ops (Dwfl_Module *dwflmod, Dwarf *dbg, int indent, int indentrest,
          break;
 
        case DW_OP_GNU_regval_type:
+         /* uleb128 register number, uleb128 CU relative
+            DW_TAG_base_type DIE offset.  */
          start = data;
          NEED (2);
          get_uleb128 (uleb, data); /* XXX check overrun */
          get_uleb128 (uleb2, data); /* XXX check overrun */
-         printf ("%*s[%4" PRIuMAX "] %s %" PRIu64 " %#" PRIx64 "\n",
+         if (! print_unresolved_addresses && cu != NULL)
+           uleb2 += cu->start;
+         printf ("%*s[%4" PRIuMAX "] %s %" PRIu64 " [%6" PRIx64 "]\n",
                  indent, "", (uintmax_t) offset, op_name, uleb, uleb2);
          CONSUME (data - start);
          offset += 1 + (data - start);
          break;
 
        case DW_OP_GNU_deref_type:
+         /* 1-byte unsigned size of value, uleb128 CU relative
+            DW_TAG_base_type DIE offset.  */
          start = data;
          NEED (2);
          usize = *(uint8_t *) data++;
          get_uleb128 (uleb, data); /* XXX check overrun */
+         if (! print_unresolved_addresses && cu != NULL)
+           uleb += cu->start;
          printf ("%*s[%4" PRIuMAX "] %s %" PRIu8 " [%6" PRIxMAX "]\n",
                  indent, "", (uintmax_t) offset,
                  op_name, usize, uleb);
@@ -4081,9 +4092,13 @@ print_ops (Dwfl_Module *dwflmod, Dwarf *dbg, int indent, int indentrest,
 
        case DW_OP_GNU_convert:
        case DW_OP_GNU_reinterpret:
+         /* uleb128 CU relative offset to DW_TAG_base_type, or zero
+            for conversion to untyped.  */
          start = data;
          NEED (1);
          get_uleb128 (uleb, data); /* XXX check overrun */
+         if (uleb != 0 && ! print_unresolved_addresses && cu != NULL)
+           uleb += cu->start;
          printf ("%*s[%4" PRIuMAX "] %s [%6" PRIxMAX "]\n",
                  indent, "", (uintmax_t) offset, op_name, uleb);
          CONSUME (data - start);