From c404826ee516d5309154f0b2dd74c0f52c1c2e40 Mon Sep 17 00:00:00 2001 From: Seva Alekseyev Date: Sat, 9 Sep 2023 22:30:11 -0400 Subject: [PATCH] Support for DW_OP_WASM_location (#500) Co-authored-by: Seva Alekseyev --- elftools/dwarf/dwarf_expr.py | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/elftools/dwarf/dwarf_expr.py b/elftools/dwarf/dwarf_expr.py index cc081dd..7d6fc7f 100644 --- a/elftools/dwarf/dwarf_expr.py +++ b/elftools/dwarf/dwarf_expr.py @@ -10,6 +10,7 @@ from collections import namedtuple from io import BytesIO from ..common.utils import struct_parse, bytelist2string, read_blob +from ..common.exceptions import DWARFError # DWARF expression opcodes. name -> opcode mapping @@ -84,6 +85,7 @@ DW_OP_name2opcode = dict( DW_OP_reinterpret=0xa9, DW_OP_lo_user=0xe0, DW_OP_GNU_push_tls_address=0xe0, + DW_OP_WASM_location=0xed, DW_OP_GNU_implicit_pointer=0xf2, DW_OP_GNU_entry_value=0xf3, DW_OP_GNU_const_type=0xf4, @@ -196,6 +198,19 @@ def _init_dispatch_table(structs): # ULEB128 with datatype DIE offset, then byte, then a blob of that size def parse_typedblob(): return lambda stream: [struct_parse(structs.Dwarf_uleb128(''), stream), read_blob(stream, struct_parse(structs.Dwarf_uint8(''), stream))] + + # https://yurydelendik.github.io/webassembly-dwarf/ + # Byte, then variant: 0, 1, 2 => uleb128, 3 => uint32 + def parse_wasmloc(): + def parse(stream): + op = struct_parse(structs.Dwarf_uint8(''), stream) + if 0 <= op <= 2: + return [op, struct_parse(structs.Dwarf_uleb128(''), stream)] + elif op == 3: + return [op, struct_parse(structs.Dwarf_uint32(''), stream)] + else: + raise DWARFError("Unknown operation code in DW_OP_WASM_location: %d" % (op,)) + return parse add('DW_OP_addr', parse_op_addr()) add('DW_OP_addrx', parse_arg_struct(structs.Dwarf_uleb128(''))) @@ -263,5 +278,6 @@ def _init_dispatch_table(structs): structs.Dwarf_sleb128(''))) add('DW_OP_GNU_parameter_ref', parse_arg_struct(structs.Dwarf_offset(''))) add('DW_OP_GNU_convert', parse_arg_struct(structs.Dwarf_uleb128(''))) + add('DW_OP_WASM_location', parse_wasmloc()) return table -- 2.30.2