#!/usr/bin/env python3 # PYTHON_ARGCOMPLETE_OK import argparse import sys from typing import ( Any, Callable, Dict, Iterator, List, Match, NoReturn, Optional, Pattern, Set, Tuple, Type, Union, ) def fail(msg: str) -> NoReturn: print(msg, file=sys.stderr) sys.exit(1) def static_assert_unreachable(x: NoReturn) -> NoReturn: raise Exception("Unreachable! " + repr(x)) # ==== COMMAND-LINE ==== if __name__ == "__main__": # Prefer to use diff_settings.py from the current working directory sys.path.insert(0, ".") try: import diff_settings except ModuleNotFoundError: fail("Unable to find diff_settings.py in the same directory.") sys.path.pop(0) try: import argcomplete except ModuleNotFoundError: argcomplete = None parser = argparse.ArgumentParser(description="Diff MIPS, PPC or AArch64 assembly.") start_argument = parser.add_argument( "start", help="Function name or address to start diffing from.", ) if argcomplete: def complete_symbol( prefix: str, parsed_args: argparse.Namespace, **kwargs: object ) -> List[str]: if not prefix or prefix.startswith("-"): # skip reading the map file, which would # result in a lot of useless completions return [] config: Dict[str, Any] = {} diff_settings.apply(config, parsed_args) # type: ignore mapfile = config.get("mapfile") if not mapfile: return [] completes = [] with open(mapfile) as f: data = f.read() # assume symbols are prefixed by a space character search = f" {prefix}" pos = data.find(search) while pos != -1: # skip the space character in the search string pos += 1 # assume symbols are suffixed by either a space # character or a (unix-style) line return spacePos = data.find(" ", pos) lineReturnPos = data.find("\n", pos) if lineReturnPos == -1: endPos = spacePos elif spacePos == -1: endPos = lineReturnPos else: endPos = min(spacePos, lineReturnPos) if endPos == -1: match = data[pos:] pos = -1 else: match = data[pos:endPos] pos = data.find(search, endPos) completes.append(match) return completes setattr(start_argument, "completer", complete_symbol) parser.add_argument( "end", nargs="?", help="Address to end diff at.", ) parser.add_argument( "-o", dest="diff_obj", action="store_true", help="""Diff .o files rather than a whole binary. This makes it possible to see symbol names. (Recommended)""", ) parser.add_argument( "-e", "--elf", dest="diff_elf_symbol", metavar="SYMBOL", help="""Diff a given function in two ELFs, one being stripped and the other one non-stripped. Requires objdump from binutils 2.33+.""", ) parser.add_argument( "-c", "--source", dest="source", action="store_true", help="Show source code (if possible). Only works with -o or -e.", ) parser.add_argument( "-C", "--source-old-binutils", dest="source_old_binutils", action="store_true", help="""Tweak --source handling to make it work with binutils < 2.33. Implies --source.""", ) parser.add_argument( "-L", "--line-numbers", dest="show_line_numbers", action="store_const", const=True, help="""Show source line numbers in output, when available. May be enabled by default depending on diff_settings.py.""", ) parser.add_argument( "--no-line-numbers", dest="show_line_numbers", action="store_const", const=False, help="Hide source line numbers in output.", ) parser.add_argument( "--inlines", dest="inlines", action="store_true", help="Show inline function calls (if possible). Only works with -o or -e.", ) parser.add_argument( "--base-asm", dest="base_asm", metavar="FILE", help="Read assembly from given file instead of configured base img.", ) parser.add_argument( "--write-asm", dest="write_asm", metavar="FILE", help="Write the current assembly output to file, e.g. for use with --base-asm.", ) parser.add_argument( "-m", "--make", dest="make", action="store_true", help="Automatically run 'make' on the .o file or binary before diffing.", ) parser.add_argument( "-l", "--skip-lines", dest="skip_lines", metavar="LINES", type=int, default=0, help="Skip the first LINES lines of output.", ) parser.add_argument( "-s", "--stop-jr-ra", dest="stop_jrra", action="store_true", help="""Stop disassembling at the first 'jr ra'. Some functions have multiple return points, so use with care!""", ) parser.add_argument( "-i", "--ignore-large-imms", dest="ignore_large_imms", action="store_true", help="Pretend all large enough immediates are the same.", ) parser.add_argument( "-I", "--ignore-addr-diffs", dest="ignore_addr_diffs", action="store_true", help="Ignore address differences. Currently only affects AArch64.", ) parser.add_argument( "-B", "--no-show-branches", dest="show_branches", action="store_false", help="Don't visualize branches/branch targets.", ) parser.add_argument( "-S", "--base-shift", dest="base_shift", metavar="N", type=str, default="0", help="""Diff position N in our img against position N + shift in the base img. Arithmetic is allowed, so e.g. |-S "0x1234 - 0x4321"| is a reasonable flag to pass if it is known that position 0x1234 in the base img syncs up with position 0x4321 in our img. Not supported together with -o.""", ) parser.add_argument( "-w", "--watch", dest="watch", action="store_true", help="""Automatically update when source/object files change. Recommended in combination with -m.""", ) parser.add_argument( "-3", "--threeway=prev", dest="threeway", action="store_const", const="prev", help="""Show a three-way diff between target asm, current asm, and asm prior to -w rebuild. Requires -w.""", ) parser.add_argument( "-b", "--threeway=base", dest="threeway", action="store_const", const="base", help="""Show a three-way diff between target asm, current asm, and asm when diff.py was started. Requires -w.""", ) parser.add_argument( "--width", dest="column_width", metavar="COLS", type=int, default=50, help="Sets the width of the left and right view column.", ) parser.add_argument( "--algorithm", dest="algorithm", default="levenshtein", choices=["levenshtein", "difflib"], help="""Diff algorithm to use. Levenshtein gives the minimum diff, while difflib aims for long sections of equal opcodes. Defaults to %(default)s.""", ) parser.add_argument( "--max-size", "--max-lines", metavar="LINES", dest="max_lines", type=int, default=1024, help="The maximum length of the diff, in lines.", ) parser.add_argument( "--no-pager", dest="no_pager", action="store_true", help="""Disable the pager; write output directly to stdout, then exit. Incompatible with --watch.""", ) parser.add_argument( "--format", choices=("color", "plain", "html", "json"), default="color", help="Output format, default is color. --format=html or json implies --no-pager.", ) parser.add_argument( "-U", "--compress-matching", metavar="N", dest="compress_matching", type=int, help="""Compress streaks of matching lines, leaving N lines of context around non-matching parts.""", ) parser.add_argument( "-V", "--compress-sameinstr", metavar="N", dest="compress_sameinstr", type=int, help="""Compress streaks of lines with same instructions (but possibly different regalloc), leaving N lines of context around other parts.""", ) # Project-specific flags, e.g. different versions/make arguments. add_custom_arguments_fn = getattr(diff_settings, "add_custom_arguments", None) if add_custom_arguments_fn: add_custom_arguments_fn(parser) if argcomplete: argcomplete.autocomplete(parser) # ==== IMPORTS ==== # (We do imports late to optimize auto-complete performance.) import abc import ast from collections import Counter, defaultdict from dataclasses import asdict, dataclass, field, replace import difflib import enum import html import itertools import json import os import queue import re import string import struct import subprocess import threading import time import traceback MISSING_PREREQUISITES = ( "Missing prerequisite python module {}. " "Run `python3 -m pip install --user colorama watchdog python-Levenshtein cxxfilt` to install prerequisites (cxxfilt only needed with --source)." ) try: from colorama import Back, Fore, Style import watchdog except ModuleNotFoundError as e: fail(MISSING_PREREQUISITES.format(e.name)) # ==== CONFIG ==== @dataclass class ProjectSettings: arch_str: str objdump_executable: str build_command: List[str] map_format: str mw_build_dir: str baseimg: Optional[str] myimg: Optional[str] mapfile: Optional[str] source_directories: Optional[List[str]] source_extensions: List[str] show_line_numbers_default: bool @dataclass class Compress: context: int same_instr: bool @dataclass class Config: arch: "ArchSettings" # Build/objdump options diff_obj: bool make: bool source: bool source_old_binutils: bool inlines: bool max_function_size_lines: int max_function_size_bytes: int # Display options formatter: "Formatter" threeway: Optional[str] base_shift: int skip_lines: int compress: Optional[Compress] show_branches: bool show_line_numbers: bool stop_jrra: bool ignore_large_imms: bool ignore_addr_diffs: bool algorithm: str # Score options score_stack_differences = True penalty_stackdiff = 1 penalty_regalloc = 5 penalty_reordering = 60 penalty_insertion = 100 penalty_deletion = 100 def create_project_settings(settings: Dict[str, Any]) -> ProjectSettings: return ProjectSettings( arch_str=settings.get("arch", "mips"), baseimg=settings.get("baseimg"), myimg=settings.get("myimg"), mapfile=settings.get("mapfile"), build_command=settings.get( "make_command", ["make", *settings.get("makeflags", [])] ), source_directories=settings.get("source_directories"), source_extensions=settings.get( "source_extensions", [".c", ".h", ".cpp", ".hpp", ".s"] ), objdump_executable=get_objdump_executable(settings.get("objdump_executable")), map_format=settings.get("map_format", "gnu"), mw_build_dir=settings.get("mw_build_dir", "build/"), show_line_numbers_default=settings.get("show_line_numbers_default", True), ) def create_config(args: argparse.Namespace, project: ProjectSettings) -> Config: formatter: Formatter if args.format == "plain": formatter = PlainFormatter(column_width=args.column_width) elif args.format == "color": formatter = AnsiFormatter(column_width=args.column_width) elif args.format == "html": formatter = HtmlFormatter() elif args.format == "json": formatter = JsonFormatter(arch_str=project.arch_str) else: raise ValueError(f"Unsupported --format: {args.format}") compress = None if args.compress_matching is not None: compress = Compress(args.compress_matching, False) if args.compress_sameinstr is not None: if compress is not None: raise ValueError( "Cannot pass both --compress-matching and --compress-sameinstr" ) compress = Compress(args.compress_sameinstr, True) show_line_numbers = args.show_line_numbers if show_line_numbers is None: show_line_numbers = project.show_line_numbers_default return Config( arch=get_arch(project.arch_str), # Build/objdump options diff_obj=args.diff_obj, make=args.make, source=args.source or args.source_old_binutils, source_old_binutils=args.source_old_binutils, inlines=args.inlines, max_function_size_lines=args.max_lines, max_function_size_bytes=args.max_lines * 4, # Display options formatter=formatter, threeway=args.threeway, base_shift=eval_int( args.base_shift, "Failed to parse --base-shift (-S) argument as an integer." ), skip_lines=args.skip_lines, compress=compress, show_branches=args.show_branches, show_line_numbers=show_line_numbers, stop_jrra=args.stop_jrra, ignore_large_imms=args.ignore_large_imms, ignore_addr_diffs=args.ignore_addr_diffs, algorithm=args.algorithm, ) def get_objdump_executable(objdump_executable: Optional[str]) -> str: if objdump_executable is not None: return objdump_executable for objdump_cand in ["mips-linux-gnu-objdump", "mips64-elf-objdump"]: try: subprocess.check_call( [objdump_cand, "--version"], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL, ) return objdump_cand except subprocess.CalledProcessError: pass except FileNotFoundError: pass return fail( "Missing binutils; please ensure mips-linux-gnu-objdump or mips64-elf-objdump exist, or configure objdump_executable." ) def get_arch(arch_str: str) -> "ArchSettings": if arch_str == "mips": return MIPS_SETTINGS if arch_str == "aarch64": return AARCH64_SETTINGS if arch_str == "ppc": return PPC_SETTINGS return fail(f"Unknown architecture: {arch_str}") BUFFER_CMD: List[str] = ["tail", "-c", str(10 ** 9)] # -S truncates long lines instead of wrapping them # -R interprets color escape sequences # -i ignores case when searching # -c something about how the screen gets redrawn; I don't remember the purpose # -#6 makes left/right arrow keys scroll by 6 characters LESS_CMD: List[str] = ["less", "-SRic", "-#6"] DEBOUNCE_DELAY: float = 0.1 # ==== FORMATTING ==== @enum.unique class BasicFormat(enum.Enum): NONE = enum.auto() IMMEDIATE = enum.auto() STACK = enum.auto() REGISTER = enum.auto() DELAY_SLOT = enum.auto() DIFF_CHANGE = enum.auto() DIFF_ADD = enum.auto() DIFF_REMOVE = enum.auto() SOURCE_FILENAME = enum.auto() SOURCE_FUNCTION = enum.auto() SOURCE_LINE_NUM = enum.auto() SOURCE_OTHER = enum.auto() @dataclass(frozen=True) class RotationFormat: group: str index: int key: str Format = Union[BasicFormat, RotationFormat] FormatFunction = Callable[[str], Format] class Text: segments: List[Tuple[str, Format]] def __init__(self, line: str = "", f: Format = BasicFormat.NONE) -> None: self.segments = [(line, f)] if line else [] def reformat(self, f: Format) -> "Text": return Text(self.plain(), f) def plain(self) -> str: return "".join(s for s, f in self.segments) def __repr__(self) -> str: return f"" def __bool__(self) -> bool: return any(s for s, f in self.segments) def __str__(self) -> str: # Use Formatter.apply(...) instead return NotImplemented def __eq__(self, other: object) -> bool: return NotImplemented def __add__(self, other: Union["Text", str]) -> "Text": if isinstance(other, str): other = Text(other) result = Text() # If two adjacent segments have the same format, merge their lines if ( self.segments and other.segments and self.segments[-1][1] == other.segments[0][1] ): result.segments = ( self.segments[:-1] + [(self.segments[-1][0] + other.segments[0][0], self.segments[-1][1])] + other.segments[1:] ) else: result.segments = self.segments + other.segments return result def __radd__(self, other: Union["Text", str]) -> "Text": if isinstance(other, str): other = Text(other) return other + self def finditer(self, pat: Pattern[str]) -> Iterator[Match[str]]: """Replacement for `pat.finditer(text)` that operates on the inner text, and returns the exact same matches as `Text.sub(pat, ...)`.""" for chunk, f in self.segments: for match in pat.finditer(chunk): yield match def sub(self, pat: Pattern[str], sub_fn: Callable[[Match[str]], "Text"]) -> "Text": result = Text() for chunk, f in self.segments: i = 0 for match in pat.finditer(chunk): start, end = match.start(), match.end() assert i <= start <= end <= len(chunk) sub = sub_fn(match) if i != start: result.segments.append((chunk[i:start], f)) result.segments.extend(sub.segments) i = end if chunk[i:]: result.segments.append((chunk[i:], f)) return result def ljust(self, column_width: int) -> "Text": length = sum(len(x) for x, _ in self.segments) return self + " " * max(column_width - length, 0) @dataclass class TableMetadata: headers: Tuple[Text, ...] current_score: int previous_score: Optional[int] class Formatter(abc.ABC): @abc.abstractmethod def apply_format(self, chunk: str, f: Format) -> str: """Apply the formatting `f` to `chunk` and escape the contents.""" ... @abc.abstractmethod def table(self, meta: TableMetadata, lines: List[Tuple["OutputLine", ...]]) -> str: """Format a multi-column table with metadata""" ... def apply(self, text: Text) -> str: return "".join(self.apply_format(chunk, f) for chunk, f in text.segments) @staticmethod def outputline_texts(lines: Tuple["OutputLine", ...]) -> Tuple[Text, ...]: return tuple([lines[0].base or Text()] + [line.fmt2 for line in lines[1:]]) @dataclass class PlainFormatter(Formatter): column_width: int def apply_format(self, chunk: str, f: Format) -> str: return chunk def table(self, meta: TableMetadata, lines: List[Tuple["OutputLine", ...]]) -> str: rows = [meta.headers] + [self.outputline_texts(ls) for ls in lines] return "\n".join( "".join(self.apply(x.ljust(self.column_width)) for x in row) for row in rows ) @dataclass class AnsiFormatter(Formatter): # Additional ansi escape codes not in colorama. See: # https://en.wikipedia.org/wiki/ANSI_escape_code#SGR_(Select_Graphic_Rendition)_parameters STYLE_UNDERLINE = "\x1b[4m" STYLE_NO_UNDERLINE = "\x1b[24m" STYLE_INVERT = "\x1b[7m" BASIC_ANSI_CODES = { BasicFormat.NONE: "", BasicFormat.IMMEDIATE: Fore.LIGHTBLUE_EX, BasicFormat.STACK: Fore.YELLOW, BasicFormat.REGISTER: Fore.YELLOW, BasicFormat.DELAY_SLOT: Fore.LIGHTBLACK_EX, BasicFormat.DIFF_CHANGE: Fore.LIGHTBLUE_EX, BasicFormat.DIFF_ADD: Fore.GREEN, BasicFormat.DIFF_REMOVE: Fore.RED, BasicFormat.SOURCE_FILENAME: Style.DIM + Style.BRIGHT, BasicFormat.SOURCE_FUNCTION: Style.DIM + Style.BRIGHT + STYLE_UNDERLINE, BasicFormat.SOURCE_LINE_NUM: Fore.LIGHTBLACK_EX, BasicFormat.SOURCE_OTHER: Style.DIM, } BASIC_ANSI_CODES_UNDO = { BasicFormat.NONE: "", BasicFormat.SOURCE_FILENAME: Style.NORMAL, BasicFormat.SOURCE_FUNCTION: Style.NORMAL + STYLE_NO_UNDERLINE, BasicFormat.SOURCE_OTHER: Style.NORMAL, } ROTATION_ANSI_COLORS = [ Fore.MAGENTA, Fore.CYAN, Fore.GREEN, Fore.RED, Fore.LIGHTYELLOW_EX, Fore.LIGHTMAGENTA_EX, Fore.LIGHTCYAN_EX, Fore.LIGHTGREEN_EX, Fore.LIGHTBLACK_EX, ] column_width: int def apply_format(self, chunk: str, f: Format) -> str: if f == BasicFormat.NONE: return chunk undo_ansi_code = Fore.RESET if isinstance(f, BasicFormat): ansi_code = self.BASIC_ANSI_CODES[f] undo_ansi_code = self.BASIC_ANSI_CODES_UNDO.get(f, undo_ansi_code) elif isinstance(f, RotationFormat): ansi_code = self.ROTATION_ANSI_COLORS[ f.index % len(self.ROTATION_ANSI_COLORS) ] else: static_assert_unreachable(f) return f"{ansi_code}{chunk}{undo_ansi_code}" def table(self, meta: TableMetadata, lines: List[Tuple["OutputLine", ...]]) -> str: rows = [(meta.headers, False)] + [ (self.outputline_texts(line), line[1].is_data_ref) for line in lines ] return "\n".join( "".join( (self.STYLE_INVERT if is_data_ref else "") + self.apply(x.ljust(self.column_width)) for x in row ) for (row, is_data_ref) in rows ) @dataclass class HtmlFormatter(Formatter): rotation_formats: int = 9 def apply_format(self, chunk: str, f: Format) -> str: chunk = html.escape(chunk) if f == BasicFormat.NONE: return chunk if isinstance(f, BasicFormat): class_name = f.name.lower().replace("_", "-") data_attr = "" elif isinstance(f, RotationFormat): class_name = f"rotation-{f.index % self.rotation_formats}" rotation_key = html.escape(f"{f.group};{f.key}", quote=True) data_attr = f'data-rotation="{rotation_key}"' else: static_assert_unreachable(f) return f"{chunk}" def table(self, meta: TableMetadata, lines: List[Tuple["OutputLine", ...]]) -> str: def table_row(line: Tuple[Text, ...], is_data_ref: bool, cell_el: str) -> str: tr_attrs = " class='data-ref'" if is_data_ref else "" output_row = f" " for cell in line: cell_html = self.apply(cell) output_row += f"<{cell_el}>{cell_html}" output_row += "\n" return output_row output = "\n" output += " \n" output += table_row(meta.headers, False, "th") output += " \n" output += " \n" output += "".join( table_row(self.outputline_texts(line), line[1].is_data_ref, "td") for line in lines ) output += " \n" output += "
\n" return output @dataclass class JsonFormatter(Formatter): arch_str: str def apply_format(self, chunk: str, f: Format) -> str: # This method is unused by this formatter return NotImplemented def table(self, meta: TableMetadata, rows: List[Tuple["OutputLine", ...]]) -> str: def serialize_format(s: str, f: Format) -> Dict[str, Any]: if f == BasicFormat.NONE: return {"text": s} elif isinstance(f, BasicFormat): return {"text": s, "format": f.name.lower()} elif isinstance(f, RotationFormat): attrs = asdict(f) attrs.update( { "text": s, "format": "rotation", } ) return attrs else: static_assert_unreachable(f) def serialize(text: Optional[Text]) -> List[Dict[str, Any]]: if text is None: return [] return [serialize_format(s, f) for s, f in text.segments] is_threeway = len(meta.headers) == 3 output: Dict[str, Any] = {} output["arch_str"] = self.arch_str output["header"] = { name: serialize(h) for h, name in zip(meta.headers, ("base", "current", "previous")) } output["current_score"] = meta.current_score if meta.previous_score is not None: output["previous_score"] = meta.previous_score output_rows: List[Dict[str, Any]] = [] for row in rows: output_row: Dict[str, Any] = {} output_row["key"] = row[0].key2 output_row["is_data_ref"] = row[1].is_data_ref iters = [ ("base", row[0].base, row[0].line1), ("current", row[1].fmt2, row[1].line2), ] if is_threeway: iters.append(("previous", row[2].fmt2, row[2].line2)) if all(line is None for _, _, line in iters): # Skip rows that were only for displaying source code continue for column_name, text, line in iters: column: Dict[str, Any] = {} column["text"] = serialize(text) if line: if line.line_num is not None: column["line"] = line.line_num if line.branch_target is not None: column["branch"] = line.branch_target if line.source_lines: column["src"] = line.source_lines if line.comment is not None: column["src_comment"] = line.comment if line.source_line_num is not None: column["src_line"] = line.source_line_num if line or column["text"]: output_row[column_name] = column output_rows.append(output_row) output["rows"] = output_rows return json.dumps(output) def format_fields( pat: Pattern[str], out1: Text, out2: Text, color1: FormatFunction, color2: Optional[FormatFunction] = None, ) -> Tuple[Text, Text]: diffs = [ of.group() != nf.group() for (of, nf) in zip(out1.finditer(pat), out2.finditer(pat)) ] it = iter(diffs) def maybe_color(color: FormatFunction, s: str) -> Text: return Text(s, color(s)) if next(it, False) else Text(s) out1 = out1.sub(pat, lambda m: maybe_color(color1, m.group())) it = iter(diffs) out2 = out2.sub(pat, lambda m: maybe_color(color2 or color1, m.group())) return out1, out2 def symbol_formatter(group: str, base_index: int) -> FormatFunction: symbol_formats: Dict[str, Format] = {} def symbol_format(s: str) -> Format: # TODO: it would be nice to use a unique Format for each symbol, so we could # add extra UI elements in the HTML version f = symbol_formats.get(s) if f is None: index = len(symbol_formats) + base_index f = RotationFormat(key=s, index=index, group=group) symbol_formats[s] = f return f return symbol_format # ==== LOGIC ==== ObjdumpCommand = Tuple[List[str], str, Optional[str]] def maybe_eval_int(expr: str) -> Optional[int]: try: ret = ast.literal_eval(expr) if not isinstance(ret, int): raise Exception("not an integer") return ret except Exception: return None def eval_int(expr: str, emsg: str) -> int: ret = maybe_eval_int(expr) if ret is None: fail(emsg) return ret def eval_line_num(expr: str) -> Optional[int]: expr = expr.strip().replace(":", "") if expr == "": return None return int(expr, 16) def run_make(target: str, project: ProjectSettings) -> None: subprocess.check_call(project.build_command + [target]) def run_make_capture_output( target: str, project: ProjectSettings ) -> "subprocess.CompletedProcess[bytes]": return subprocess.run( project.build_command + [target], stderr=subprocess.PIPE, stdout=subprocess.PIPE, ) def restrict_to_function(dump: str, fn_name: str) -> str: try: ind = dump.index("\n", dump.index(f"<{fn_name}>:")) return dump[ind + 1 :] except ValueError: return "" def serialize_data_references(references: List[Tuple[int, int, str]]) -> str: return "".join( f"DATAREF {text_offset} {from_offset} {from_section}\n" for (text_offset, from_offset, from_section) in references ) def maybe_get_objdump_source_flags(config: Config) -> List[str]: flags = [] if config.show_line_numbers or config.source: flags.append("--line-numbers") if config.source: flags.append("--source") if not config.source_old_binutils: flags.append("--source-comment=│ ") if config.inlines: flags.append("--inlines") return flags def run_objdump(cmd: ObjdumpCommand, config: Config, project: ProjectSettings) -> str: flags, target, restrict = cmd try: out = subprocess.run( [project.objdump_executable] + config.arch.arch_flags + flags + [target], check=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE, universal_newlines=True, ).stdout except subprocess.CalledProcessError as e: print(e.stdout) print(e.stderr) if "unrecognized option '--source-comment" in e.stderr: fail("** Try using --source-old-binutils instead of --source **") raise e if restrict is not None: out = restrict_to_function(out, restrict) if config.diff_obj: with open(target, "rb") as f: data = f.read() out = serialize_data_references(parse_elf_data_references(data)) + out else: for i in range(7): out = out[out.find("\n") + 1 :] out = out.rstrip("\n") return out def search_map_file( fn_name: str, project: ProjectSettings ) -> Tuple[Optional[str], Optional[int]]: if not project.mapfile: fail(f"No map file configured; cannot find function {fn_name}.") try: with open(project.mapfile) as f: contents = f.read() except Exception: fail(f"Failed to open map file {project.mapfile} for reading.") if project.map_format == "gnu": lines = contents.split("\n") try: cur_objfile = None ram_to_rom = None cands = [] last_line = "" for line in lines: if line.startswith(" .text"): cur_objfile = line.split()[3] if "load address" in line: tokens = last_line.split() + line.split() ram = int(tokens[1], 0) rom = int(tokens[5], 0) ram_to_rom = rom - ram if line.endswith(" " + fn_name): ram = int(line.split()[0], 0) if cur_objfile is not None and ram_to_rom is not None: cands.append((cur_objfile, ram + ram_to_rom)) last_line = line except Exception as e: traceback.print_exc() fail(f"Internal error while parsing map file") if len(cands) > 1: fail(f"Found multiple occurrences of function {fn_name} in map file.") if len(cands) == 1: return cands[0] elif project.map_format == "mw": find = re.findall( re.compile( # ram elf rom r" \S+ \S+ (\S+) (\S+) . " + fn_name # object name + r"(?: \(entry of \.(?:init|text)\))? \t(\S+)" ), contents, ) if len(find) > 1: fail(f"Found multiple occurrences of function {fn_name} in map file.") if len(find) == 1: rom = int(find[0][1], 16) objname = find[0][2] # The metrowerks linker map format does not contain the full object path, # so we must complete it manually. objfiles = [ os.path.join(dirpath, f) for dirpath, _, filenames in os.walk(project.mw_build_dir) for f in filenames if f == objname ] if len(objfiles) > 1: all_objects = "\n".join(objfiles) fail( f"Found multiple objects of the same name {objname} in {project.mw_build_dir}, " f"cannot determine which to diff against: \n{all_objects}" ) if len(objfiles) == 1: objfile = objfiles[0] # TODO Currently the ram-rom conversion only works for diffing ELF # executables, but it would likely be more convenient to diff DOLs. # At this time it is recommended to always use -o when running the diff # script as this mode does not make use of the ram-rom conversion. return objfile, rom else: fail(f"Linker map format {project.map_format} unrecognised.") return None, None def parse_elf_data_references(data: bytes) -> List[Tuple[int, int, str]]: e_ident = data[:16] if e_ident[:4] != b"\x7FELF": return [] SHT_SYMTAB = 2 SHT_REL = 9 SHT_RELA = 4 is_32bit = e_ident[4] == 1 is_little_endian = e_ident[5] == 1 str_end = "<" if is_little_endian else ">" str_off = "I" if is_32bit else "Q" sym_size = {"B": 1, "H": 2, "I": 4, "Q": 8} def read(spec: str, offset: int) -> Tuple[int, ...]: spec = spec.replace("P", str_off) size = struct.calcsize(spec) return struct.unpack(str_end + spec, data[offset : offset + size]) ( e_type, e_machine, e_version, e_entry, e_phoff, e_shoff, e_flags, e_ehsize, e_phentsize, e_phnum, e_shentsize, e_shnum, e_shstrndx, ) = read("HHIPPPIHHHHHH", 16) if e_type != 1: # relocatable return [] assert e_shoff != 0 assert e_shnum != 0 # don't support > 0xFF00 sections assert e_shstrndx != 0 @dataclass class Section: sh_name: int sh_type: int sh_flags: int sh_addr: int sh_offset: int sh_size: int sh_link: int sh_info: int sh_addralign: int sh_entsize: int sections = [ Section(*read("IIPPPPIIPP", e_shoff + i * e_shentsize)) for i in range(e_shnum) ] shstr = sections[e_shstrndx] sec_name_offs = [shstr.sh_offset + s.sh_name for s in sections] sec_names = [data[offset : data.index(b"\0", offset)] for offset in sec_name_offs] symtab_sections = [i for i in range(e_shnum) if sections[i].sh_type == SHT_SYMTAB] assert len(symtab_sections) == 1 symtab = sections[symtab_sections[0]] text_sections = [i for i in range(e_shnum) if sec_names[i] == b".text"] assert len(text_sections) == 1 text_section = text_sections[0] ret: List[Tuple[int, int, str]] = [] for s in sections: if s.sh_type == SHT_REL or s.sh_type == SHT_RELA: if s.sh_info == text_section: # Skip .text -> .text references continue sec_name = sec_names[s.sh_info].decode("latin1") sec_base = sections[s.sh_info].sh_offset for i in range(0, s.sh_size, s.sh_entsize): if s.sh_type == SHT_REL: r_offset, r_info = read("PP", s.sh_offset + i) else: r_offset, r_info, r_addend = read("PPP", s.sh_offset + i) if is_32bit: r_sym = r_info >> 8 r_type = r_info & 0xFF sym_offset = symtab.sh_offset + symtab.sh_entsize * r_sym st_name, st_value, st_size, st_info, st_other, st_shndx = read( "IIIBBH", sym_offset ) else: r_sym = r_info >> 32 r_type = r_info & 0xFFFFFFFF sym_offset = symtab.sh_offset + symtab.sh_entsize * r_sym st_name, st_info, st_other, st_shndx, st_value, st_size = read( "IBBHQQ", sym_offset ) if st_shndx == text_section: if s.sh_type == SHT_REL: if e_machine == 8 and r_type == 2: # R_MIPS_32 (r_addend,) = read("I", sec_base + r_offset) else: continue text_offset = (st_value + r_addend) & 0xFFFFFFFF ret.append((text_offset, r_offset, sec_name)) return ret def dump_elf( start: str, end: Optional[str], diff_elf_symbol: str, config: Config, project: ProjectSettings, ) -> Tuple[str, ObjdumpCommand, ObjdumpCommand]: if not project.baseimg or not project.myimg: fail("Missing myimg/baseimg in config.") if config.base_shift: fail("--base-shift not compatible with -e") start_addr = eval_int(start, "Start address must be an integer expression.") if end is not None: end_addr = eval_int(end, "End address must be an integer expression.") else: end_addr = start_addr + config.max_function_size_bytes flags1 = [ f"--start-address={start_addr}", f"--stop-address={end_addr}", ] flags2 = [ f"--disassemble={diff_elf_symbol}", ] objdump_flags = ["-drz", "-j", ".text"] return ( project.myimg, (objdump_flags + flags1, project.baseimg, None), ( objdump_flags + flags2 + maybe_get_objdump_source_flags(config), project.myimg, None, ), ) def dump_objfile( start: str, end: Optional[str], config: Config, project: ProjectSettings ) -> Tuple[str, ObjdumpCommand, ObjdumpCommand]: if config.base_shift: fail("--base-shift not compatible with -o") if end is not None: fail("end address not supported together with -o") if start.startswith("0"): fail("numerical start address not supported with -o; pass a function name") objfile, _ = search_map_file(start, project) if not objfile: fail("Not able to find .o file for function.") if config.make: run_make(objfile, project) if not os.path.isfile(objfile): fail(f"Not able to find .o file for function: {objfile} is not a file.") refobjfile = "expected/" + objfile if not os.path.isfile(refobjfile): fail(f'Please ensure an OK .o file exists at "{refobjfile}".') objdump_flags = ["-drz", "-j", ".text"] return ( objfile, (objdump_flags, refobjfile, start), (objdump_flags + maybe_get_objdump_source_flags(config), objfile, start), ) def dump_binary( start: str, end: Optional[str], config: Config, project: ProjectSettings ) -> Tuple[str, ObjdumpCommand, ObjdumpCommand]: if not project.baseimg or not project.myimg: fail("Missing myimg/baseimg in config.") if config.make: run_make(project.myimg, project) start_addr = maybe_eval_int(start) if start_addr is None: _, start_addr = search_map_file(start, project) if start_addr is None: fail("Not able to find function in map file.") if end is not None: end_addr = eval_int(end, "End address must be an integer expression.") else: end_addr = start_addr + config.max_function_size_bytes objdump_flags = ["-Dz", "-bbinary", "-EB"] flags1 = [ f"--start-address={start_addr + config.base_shift}", f"--stop-address={end_addr + config.base_shift}", ] flags2 = [f"--start-address={start_addr}", f"--stop-address={end_addr}"] return ( project.myimg, (objdump_flags + flags1, project.baseimg, None), (objdump_flags + flags2, project.myimg, None), ) class DifferenceNormalizer: def __init__(self, config: Config) -> None: self.config = config def normalize(self, mnemonic: str, row: str) -> str: """This should be called exactly once for each line.""" arch = self.config.arch row = self._normalize_arch_specific(mnemonic, row) if self.config.ignore_large_imms and mnemonic not in arch.branch_instructions: row = re.sub(self.config.arch.re_large_imm, "", row) return row def _normalize_arch_specific(self, mnemonic: str, row: str) -> str: return row class DifferenceNormalizerAArch64(DifferenceNormalizer): def __init__(self, config: Config) -> None: super().__init__(config) self._adrp_pair_registers: Set[str] = set() def _normalize_arch_specific(self, mnemonic: str, row: str) -> str: if self.config.ignore_addr_diffs: row = self._normalize_adrp_differences(mnemonic, row) row = self._normalize_bl(mnemonic, row) return row def _normalize_bl(self, mnemonic: str, row: str) -> str: if mnemonic != "bl": return row row, _ = split_off_address(row) return row + "" def _normalize_adrp_differences(self, mnemonic: str, row: str) -> str: """Identifies ADRP + LDR/ADD pairs that are used to access the GOT and suppresses any immediate differences. Whenever an ADRP is seen, the destination register is added to the set of registers that are part of an ADRP + LDR/ADD pair. Registers are removed from the set as soon as they are used for an LDR or ADD instruction which completes the pair. This method is somewhat crude but should manage to detect most such pairs. """ row_parts = row.split("\t", 1) if mnemonic == "adrp": self._adrp_pair_registers.add(row_parts[1].strip().split(",")[0]) row, _ = split_off_address(row) return row + "" elif mnemonic == "ldr": for reg in self._adrp_pair_registers: # ldr xxx, [reg] # ldr xxx, [reg, ] if f", [{reg}" in row_parts[1]: self._adrp_pair_registers.remove(reg) return normalize_imms(row, AARCH64_SETTINGS) elif mnemonic == "add": for reg in self._adrp_pair_registers: # add reg, reg, if row_parts[1].startswith(f"{reg}, {reg}, "): self._adrp_pair_registers.remove(reg) return normalize_imms(row, AARCH64_SETTINGS) return row @dataclass class ArchSettings: re_int: Pattern[str] re_comment: Pattern[str] re_reg: Pattern[str] re_sprel: Pattern[str] re_large_imm: Pattern[str] re_imm: Pattern[str] branch_instructions: Set[str] instructions_with_address_immediates: Set[str] forbidden: Set[str] = field(default_factory=lambda: set(string.ascii_letters + "_")) arch_flags: List[str] = field(default_factory=list) branch_likely_instructions: Set[str] = field(default_factory=set) difference_normalizer: Type[DifferenceNormalizer] = DifferenceNormalizer MIPS_BRANCH_LIKELY_INSTRUCTIONS = { "beql", "bnel", "beqzl", "bnezl", "bgezl", "bgtzl", "blezl", "bltzl", "bc1tl", "bc1fl", } MIPS_BRANCH_INSTRUCTIONS = MIPS_BRANCH_LIKELY_INSTRUCTIONS.union( { "b", "beq", "bne", "beqz", "bnez", "bgez", "bgtz", "blez", "bltz", "bc1t", "bc1f", } ) AARCH64_BRANCH_INSTRUCTIONS = { "bl", "b", "b.eq", "b.ne", "b.cs", "b.hs", "b.cc", "b.lo", "b.mi", "b.pl", "b.vs", "b.vc", "b.hi", "b.ls", "b.ge", "b.lt", "b.gt", "b.le", "cbz", "cbnz", "tbz", "tbnz", } PPC_BRANCH_INSTRUCTIONS = { "b", "beq", "beq+", "beq-", "bne", "bne+", "bne-", "blt", "blt+", "blt-", "ble", "ble+", "ble-", "bdnz", "bdnz+", "bdnz-", "bge", "bge+", "bge-", "bgt", "bgt+", "bgt-", } MIPS_SETTINGS = ArchSettings( re_int=re.compile(r"[0-9]+"), re_comment=re.compile(r"<.*?>"), re_reg=re.compile( r"\$?\b(a[0-3]|t[0-9]|s[0-8]|at|v[01]|f[12]?[0-9]|f3[01]|k[01]|fp|ra|zero)\b" ), re_sprel=re.compile(r"(?<=,)([0-9]+|0x[0-9a-f]+)\(sp\)"), re_large_imm=re.compile(r"-?[1-9][0-9]{2,}|-?0x[0-9a-f]{3,}"), re_imm=re.compile(r"(\b|-)([0-9]+|0x[0-9a-fA-F]+)\b(?!\(sp)|%(lo|hi)\([^)]*\)"), arch_flags=["-m", "mips:4300"], branch_likely_instructions=MIPS_BRANCH_LIKELY_INSTRUCTIONS, branch_instructions=MIPS_BRANCH_INSTRUCTIONS, instructions_with_address_immediates=MIPS_BRANCH_INSTRUCTIONS.union({"jal", "j"}), ) AARCH64_SETTINGS = ArchSettings( re_int=re.compile(r"[0-9]+"), re_comment=re.compile(r"(<.*?>|//.*$)"), # GPRs and FP registers: X0-X30, W0-W30, [DSHQ]0..31 # The zero registers and SP should not be in this list. re_reg=re.compile(r"\$?\b([dshq][12]?[0-9]|[dshq]3[01]|[xw][12]?[0-9]|[xw]30)\b"), re_sprel=re.compile(r"sp, #-?(0x[0-9a-fA-F]+|[0-9]+)\b"), re_large_imm=re.compile(r"-?[1-9][0-9]{2,}|-?0x[0-9a-f]{3,}"), re_imm=re.compile(r"(?|//.*$)"), re_reg=re.compile(r"\$?\b([rf][0-9]+)\b"), re_sprel=re.compile(r"(?<=,)(-?[0-9]+|-?0x[0-9a-f]+)\(r1\)"), re_large_imm=re.compile(r"-?[1-9][0-9]{2,}|-?0x[0-9a-f]{3,}"), re_imm=re.compile(r"(\b|-)([0-9]+|0x[0-9a-fA-F]+)\b(?!\(r1)|[^@]*@(ha|h|lo)"), branch_instructions=PPC_BRANCH_INSTRUCTIONS, instructions_with_address_immediates=PPC_BRANCH_INSTRUCTIONS.union({"bl"}), ) def hexify_int(row: str, pat: Match[str], arch: ArchSettings) -> str: full = pat.group(0) if len(full) <= 1: # leave one-digit ints alone return full start, end = pat.span() if start and row[start - 1] in arch.forbidden: return full if end < len(row) and row[end] in arch.forbidden: return full return hex(int(full)) def parse_relocated_line(line: str) -> Tuple[str, str, str]: for c in ",\t ": if c in line: ind2 = line.rindex(c) break else: raise Exception(f"failed to parse relocated line: {line}") before = line[: ind2 + 1] after = line[ind2 + 1 :] ind2 = after.find("(") if ind2 == -1: imm, after = after, "" else: imm, after = after[:ind2], after[ind2:] if imm == "0x0": imm = "0" return before, imm, after def process_mips_reloc(row: str, prev: str, arch: ArchSettings) -> str: before, imm, after = parse_relocated_line(prev) repl = row.split()[-1] if imm != "0": # MIPS uses relocations with addends embedded in the code as immediates. # If there is an immediate, show it as part of the relocation. Ideally # we'd show this addend in both %lo/%hi, but annoyingly objdump's output # doesn't include enough information to pair up %lo's and %hi's... # TODO: handle unambiguous cases where all addends for a symbol are the # same, or show "+???". mnemonic = prev.split()[0] if ( mnemonic in arch.instructions_with_address_immediates and not imm.startswith("0x") ): imm = "0x" + imm repl += "+" + imm if int(imm, 0) > 0 else imm if "R_MIPS_LO16" in row: repl = f"%lo({repl})" elif "R_MIPS_HI16" in row: # Ideally we'd pair up R_MIPS_LO16 and R_MIPS_HI16 to generate a # correct addend for each, but objdump doesn't give us the order of # the relocations, so we can't find the right LO16. :( repl = f"%hi({repl})" elif "R_MIPS_26" in row: # Function calls pass elif "R_MIPS_PC16" in row: # Branch to glabel. This gives confusing output, but there's not much # we can do here. pass else: assert False, f"unknown relocation type '{row}' for line '{prev}'" return before + repl + after def process_ppc_reloc(row: str, prev: str) -> str: assert any( r in row for r in ["R_PPC_REL24", "R_PPC_ADDR16", "R_PPC_EMB_SDA21"] ), f"unknown relocation type '{row}' for line '{prev}'" before, imm, after = parse_relocated_line(prev) repl = row.split()[-1] if "R_PPC_REL24" in row: # function calls pass elif "R_PPC_ADDR16_HI" in row: # absolute hi of addr repl = f"{repl}@h" elif "R_PPC_ADDR16_HA" in row: # adjusted hi of addr repl = f"{repl}@ha" elif "R_PPC_ADDR16_LO" in row: # lo of addr repl = f"{repl}@l" elif "R_PPC_ADDR16" in row: # 16-bit absolute addr if "+0x7" in repl: # remove the very large addends as they are an artifact of (label-_SDA(2)_BASE_) # computations and are unimportant in a diff setting. if int(repl.split("+")[1], 16) > 0x70000000: repl = repl.split("+")[0] elif "R_PPC_EMB_SDA21" in row: # small data area pass return before + repl + after def pad_mnemonic(line: str) -> str: if "\t" not in line: return line mn, args = line.split("\t", 1) return f"{mn:<7s} {args}" @dataclass class Line: mnemonic: str diff_row: str original: str normalized_original: str scorable_line: str line_num: Optional[int] = None branch_target: Optional[int] = None source_filename: Optional[str] = None source_line_num: Optional[int] = None source_lines: List[str] = field(default_factory=list) comment: Optional[str] = None def process(dump: str, config: Config) -> List[Line]: arch = config.arch normalizer = arch.difference_normalizer(config) skip_next = False source_lines = [] source_filename = None source_line_num = None i = 0 num_instr = 0 data_refs: Dict[int, Dict[str, List[int]]] = defaultdict(lambda: defaultdict(list)) output: List[Line] = [] stop_after_delay_slot = False lines = dump.split("\n") while i < len(lines): row = lines[i] i += 1 if config.diff_obj and (">:" in row or not row): continue if row.startswith("DATAREF"): parts = row.split(" ", 3) text_offset = int(parts[1]) from_offset = int(parts[2]) from_section = parts[3] data_refs[text_offset][from_section].append(from_offset) continue if config.diff_obj and num_instr >= config.max_function_size_lines: output.append( Line( mnemonic="...", diff_row="...", original="...", normalized_original="...", scorable_line="...", ) ) break # This regex is conservative, and assumes the file path does not contain "weird" # characters like colons, tabs, or angle brackets. if ( config.show_line_numbers and row and re.match( r"^[^ \t<>:][^\t<>:]*:[0-9]+( \(discriminator [0-9]+\))?$", row ) ): source_filename, _, tail = row.rpartition(":") source_line_num = int(tail.partition(" ")[0]) if config.source: source_lines.append(row) continue if config.source and not config.source_old_binutils and (row and row[0] != " "): source_lines.append(row) continue if ( config.source and config.source_old_binutils and (row and not re.match(r"^ +[0-9a-f]+:\t", row)) ): source_lines.append(row) continue # `objdump --line-numbers` includes function markers, even without `--source` if config.show_line_numbers and row and re.match(r"^[^ \t]+\(\):$", row): continue m_comment = re.search(arch.re_comment, row) comment = m_comment[0] if m_comment else None row = re.sub(arch.re_comment, "", row) row = row.rstrip() tabs = row.split("\t") row = "\t".join(tabs[2:]) line_num = eval_line_num(tabs[0].strip()) if line_num in data_refs: refs = data_refs[line_num] ref_str = "; ".join( section_name + "+" + ",".join(hex(off) for off in offs) for section_name, offs in refs.items() ) output.append( Line( mnemonic="", diff_row="", original=ref_str, normalized_original=ref_str, scorable_line="", ) ) if "\t" in row: row_parts = row.split("\t", 1) else: # powerpc-eabi-objdump doesn't use tabs row_parts = [part.lstrip() for part in row.split(" ", 1)] mnemonic = row_parts[0].strip() if mnemonic not in arch.instructions_with_address_immediates: row = re.sub(arch.re_int, lambda m: hexify_int(row, m, arch), row) # Let 'original' be 'row' with relocations applied, while we continue # transforming 'row' into a coarser version that ignores registers and # immediates. original = row while i < len(lines): reloc_row = lines[i] if "R_AARCH64_" in reloc_row: # TODO: handle relocation pass elif "R_MIPS_" in reloc_row: original = process_mips_reloc(reloc_row, original, arch) elif "R_PPC_" in reloc_row: original = process_ppc_reloc(reloc_row, original) else: break i += 1 normalized_original = normalizer.normalize(mnemonic, original) scorable_line = normalized_original if not config.score_stack_differences: scorable_line = re.sub(arch.re_sprel, "addr(sp)", scorable_line) if mnemonic in arch.branch_instructions: # Replace the final argument with "" scorable_line = re.sub(r"[^, \t]+$", "", scorable_line) if skip_next: skip_next = False row = "" mnemonic = "" scorable_line = "" if mnemonic in arch.branch_likely_instructions: skip_next = True row = re.sub(arch.re_reg, "", row) row = re.sub(arch.re_sprel, "addr(sp)", row) row_with_imm = row if mnemonic in arch.instructions_with_address_immediates: row = row.strip() row, _ = split_off_address(row) row += "" else: row = normalize_imms(row, arch) branch_target = None if mnemonic in arch.branch_instructions: branch_target = int(row_parts[1].strip().split(",")[-1], 16) if mnemonic in arch.branch_likely_instructions: branch_target -= 4 output.append( Line( mnemonic=mnemonic, diff_row=row, original=original, normalized_original=normalized_original, scorable_line=scorable_line, line_num=line_num, branch_target=branch_target, source_filename=source_filename, source_line_num=source_line_num, source_lines=source_lines, comment=comment, ) ) num_instr += 1 source_lines = [] if config.stop_jrra and mnemonic == "jr" and row_parts[1].strip() == "ra": stop_after_delay_slot = True elif stop_after_delay_slot: break return output def normalize_imms(row: str, arch: ArchSettings) -> str: return re.sub(arch.re_imm, "", row) def normalize_stack(row: str, arch: ArchSettings) -> str: return re.sub(arch.re_sprel, "addr(sp)", row) def imm_matches_everything(row: str, arch: ArchSettings) -> bool: # (this should probably be arch-specific) return "(." in row def split_off_address(line: str) -> Tuple[str, str]: """Split e.g. 'beqz $r0,1f0' into 'beqz $r0,' and '1f0'.""" parts = line.split(",") if len(parts) < 2: parts = line.split(None, 1) off = len(line) - len(parts[-1]) return line[:off], line[off:] def diff_sequences_difflib( seq1: List[str], seq2: List[str] ) -> List[Tuple[str, int, int, int, int]]: differ = difflib.SequenceMatcher(a=seq1, b=seq2, autojunk=False) return differ.get_opcodes() def diff_sequences( seq1: List[str], seq2: List[str], algorithm: str ) -> List[Tuple[str, int, int, int, int]]: if ( algorithm != "levenshtein" or len(seq1) * len(seq2) > 4 * 10 ** 8 or len(seq1) + len(seq2) >= 0x110000 ): return diff_sequences_difflib(seq1, seq2) # The Levenshtein library assumes that we compare strings, not lists. Convert. # (Per the check above we know we have fewer than 0x110000 unique elements, so chr() works.) remapping: Dict[str, str] = {} def remap(seq: List[str]) -> str: seq = seq[:] for i in range(len(seq)): val = remapping.get(seq[i]) if val is None: val = chr(len(remapping)) remapping[seq[i]] = val seq[i] = val return "".join(seq) rem1 = remap(seq1) rem2 = remap(seq2) import Levenshtein ret: List[Tuple[str, int, int, int, int]] = Levenshtein.opcodes(rem1, rem2) return ret def diff_lines( lines1: List[Line], lines2: List[Line], algorithm: str, ) -> List[Tuple[Optional[Line], Optional[Line]]]: ret = [] for (tag, i1, i2, j1, j2) in diff_sequences( [line.mnemonic for line in lines1], [line.mnemonic for line in lines2], algorithm, ): for line1, line2 in itertools.zip_longest(lines1[i1:i2], lines2[j1:j2]): if tag == "replace": if line1 is None: tag = "insert" elif line2 is None: tag = "delete" elif tag == "insert": assert line1 is None elif tag == "delete": assert line2 is None ret.append((line1, line2)) return ret def score_diff_lines( lines: List[Tuple[Optional[Line], Optional[Line]]], config: Config ) -> int: # This logic is copied from `scorer.py` from the decomp permuter project # https://github.com/simonlindholm/decomp-permuter/blob/main/src/scorer.py score = 0 deletions = [] insertions = [] def lo_hi_match(old: str, new: str) -> bool: # TODO: Make this arch-independent, like `imm_matches_everything()` old_lo = old.find("%lo") old_hi = old.find("%hi") new_lo = new.find("%lo") new_hi = new.find("%hi") if old_lo != -1 and new_lo != -1: old_idx = old_lo new_idx = new_lo elif old_hi != -1 and new_hi != -1: old_idx = old_hi new_idx = new_hi else: return False if old[:old_idx] != new[:new_idx]: return False old_inner = old[old_idx + 4 : -1] new_inner = new[new_idx + 4 : -1] return old_inner.startswith(".") or new_inner.startswith(".") def diff_sameline(old: str, new: str) -> None: nonlocal score if old == new: return if lo_hi_match(old, new): return ignore_last_field = False if config.score_stack_differences: oldsp = re.search(config.arch.re_sprel, old) newsp = re.search(config.arch.re_sprel, new) if oldsp and newsp: oldrel = int(oldsp.group(1) or "0", 0) newrel = int(newsp.group(1) or "0", 0) score += abs(oldrel - newrel) * config.penalty_stackdiff ignore_last_field = True # Probably regalloc difference, or signed vs unsigned # Compare each field in order newfields, oldfields = new.split(","), old.split(",") if ignore_last_field: newfields = newfields[:-1] oldfields = oldfields[:-1] for nf, of in zip(newfields, oldfields): if nf != of: score += config.penalty_regalloc # Penalize any extra fields score += abs(len(newfields) - len(oldfields)) * config.penalty_regalloc def diff_insert(line: str) -> None: # Reordering or totally different codegen. # Defer this until later when we can tell. insertions.append(line) def diff_delete(line: str) -> None: deletions.append(line) # Find the end of the last long streak of matching mnemonics, if it looks # like the objdump output was truncated. This is used to skip scoring # misaligned lines at the end of the diff. last_mismatch = -1 max_index = None lines_were_truncated = False for index, (line1, line2) in enumerate(lines): if (line1 and line1.original == "...") or (line2 and line2.original == "..."): lines_were_truncated = True if line1 and line2 and line1.mnemonic == line2.mnemonic: if index - last_mismatch >= 50: max_index = index else: last_mismatch = index if not lines_were_truncated: max_index = None for index, (line1, line2) in enumerate(lines): if max_index is not None and index > max_index: break if line1 and line2 and line1.mnemonic == line2.mnemonic: diff_sameline(line1.scorable_line, line2.scorable_line) else: if line1: diff_delete(line1.scorable_line) if line2: diff_insert(line2.scorable_line) insertions_co = Counter(insertions) deletions_co = Counter(deletions) for item in insertions_co + deletions_co: ins = insertions_co[item] dels = deletions_co[item] common = min(ins, dels) score += ( (ins - common) * config.penalty_insertion + (dels - common) * config.penalty_deletion + config.penalty_reordering * common ) return score @dataclass(frozen=True) class OutputLine: base: Optional[Text] = field(compare=False) fmt2: Text = field(compare=False) key2: Optional[str] boring: bool = field(compare=False) is_data_ref: bool = field(compare=False) line1: Optional[Line] = field(compare=False) line2: Optional[Line] = field(compare=False) @dataclass(frozen=True) class Diff: lines: List[OutputLine] score: int def do_diff(lines1: List[Line], lines2: List[Line], config: Config) -> Diff: if config.source: import cxxfilt arch = config.arch fmt = config.formatter output: List[OutputLine] = [] sc1 = symbol_formatter("base-reg", 0) sc2 = symbol_formatter("my-reg", 0) sc3 = symbol_formatter("base-stack", 4) sc4 = symbol_formatter("my-stack", 4) sc5 = symbol_formatter("base-branch", 0) sc6 = symbol_formatter("my-branch", 0) bts1: Set[int] = set() bts2: Set[int] = set() if config.show_branches: for (lines, btset, sc) in [ (lines1, bts1, sc5), (lines2, bts2, sc6), ]: for line in lines: bt = line.branch_target if bt is not None: btset.add(bt) sc(str(bt)) diffed_lines = diff_lines(lines1, lines2, config.algorithm) score = score_diff_lines(diffed_lines, config) line_num_base = -1 line_num_offset = 0 line_num_2to1 = {} for (line1, line2) in diffed_lines: if line1 is not None and line1.line_num is not None: line_num_base = line1.line_num line_num_offset = 0 else: line_num_offset += 1 if line2 is not None and line2.line_num is not None: line_num_2to1[line2.line_num] = (line_num_base, line_num_offset) for (line1, line2) in diffed_lines: line_color1 = line_color2 = sym_color = BasicFormat.NONE line_prefix = " " is_data_ref = False out1 = Text() if not line1 else Text(pad_mnemonic(line1.original)) out2 = Text() if not line2 else Text(pad_mnemonic(line2.original)) if line1 and line2 and line1.diff_row == line2.diff_row: if line1.diff_row == "": if line1.normalized_original != line2.normalized_original: line_prefix = "i" sym_color = BasicFormat.DIFF_CHANGE out1 = out1.reformat(sym_color) out2 = out2.reformat(sym_color) is_data_ref = True elif ( line1.normalized_original == line2.normalized_original and line2.branch_target is None ): # Fast path: no coloring needed. We don't include branch instructions # in this case because we need to check that their targets line up in # the diff, and don't just happen to have the are the same address # by accident. pass elif line1.diff_row == "": # Don't draw attention to differing branch-likely delay slots: they # typically mirror the branch destination - 1 so the real difference # is elsewhere. Still, do mark them as different to avoid confusion. # No need to consider branches because delay slots can't branch. out1 = out1.reformat(BasicFormat.DELAY_SLOT) out2 = out2.reformat(BasicFormat.DELAY_SLOT) else: mnemonic = line1.original.split()[0] branchless1, address1 = out1.plain(), "" branchless2, address2 = out2.plain(), "" if mnemonic in arch.instructions_with_address_immediates: branchless1, address1 = split_off_address(branchless1) branchless2, address2 = split_off_address(branchless2) out1 = Text(branchless1) out2 = Text(branchless2) out1, out2 = format_fields( arch.re_imm, out1, out2, lambda _: BasicFormat.IMMEDIATE ) if line2.branch_target is not None: target = line2.branch_target line2_target = line_num_2to1.get(line2.branch_target) if line2_target is None: # If the target is outside the disassembly, extrapolate. # This only matters near the bottom. assert line2.line_num is not None line2_line = line_num_2to1[line2.line_num] line2_target = (line2_line[0] + (target - line2.line_num), 0) # Set the key for three-way diffing to a normalized version. norm2, norm_branch2 = split_off_address(line2.normalized_original) if norm_branch2 != "": line2.normalized_original = norm2 + str(line2_target) same_target = line2_target == (line1.branch_target, 0) else: # Do a naive comparison for non-branches (e.g. function calls). same_target = address1 == address2 if normalize_imms(branchless1, arch) == normalize_imms( branchless2, arch ): if imm_matches_everything(branchless2, arch): # ignore differences due to %lo(.rodata + ...) vs symbol out1 = out1.reformat(BasicFormat.NONE) out2 = out2.reformat(BasicFormat.NONE) elif line2.branch_target is not None and same_target: # same-target branch, don't color pass else: # must have an imm difference (or else we would have hit the # fast path) sym_color = BasicFormat.IMMEDIATE line_prefix = "i" else: out1, out2 = format_fields(arch.re_sprel, out1, out2, sc3, sc4) if normalize_stack(branchless1, arch) == normalize_stack( branchless2, arch ): # only stack differences (luckily stack and imm # differences can't be combined in MIPS, so we # don't have to think about that case) sym_color = BasicFormat.STACK line_prefix = "s" else: # reg differences and maybe imm as well out1, out2 = format_fields(arch.re_reg, out1, out2, sc1, sc2) line_color1 = line_color2 = sym_color = BasicFormat.REGISTER line_prefix = "r" if same_target: address_imm_fmt = BasicFormat.NONE else: address_imm_fmt = BasicFormat.IMMEDIATE out1 += Text(address1, address_imm_fmt) out2 += Text(address2, address_imm_fmt) elif line1 and line2: line_prefix = "|" line_color1 = line_color2 = sym_color = BasicFormat.DIFF_CHANGE out1 = out1.reformat(line_color1) out2 = out2.reformat(line_color2) elif line1: line_prefix = "<" line_color1 = sym_color = BasicFormat.DIFF_REMOVE out1 = out1.reformat(line_color1) out2 = Text() elif line2: line_prefix = ">" line_color2 = sym_color = BasicFormat.DIFF_ADD out1 = Text() out2 = out2.reformat(line_color2) if config.source and line2 and line2.comment: out2 += f" {line2.comment}" def format_part( out: Text, line: Optional[Line], line_color: Format, btset: Set[int], sc: FormatFunction, ) -> Optional[Text]: if line is None: return None if line.line_num is None: return out in_arrow = Text(" ") out_arrow = Text() if config.show_branches: if line.line_num in btset: in_arrow = Text("~>", sc(str(line.line_num))) if line.branch_target is not None: out_arrow = " " + Text("~>", sc(str(line.branch_target))) formatted_line_num = Text(hex(line.line_num)[2:] + ":", line_color) return formatted_line_num + " " + in_arrow + " " + out + out_arrow part1 = format_part(out1, line1, line_color1, bts1, sc5) part2 = format_part(out2, line2, line_color2, bts2, sc6) if line2: for source_line in line2.source_lines: line_format = BasicFormat.SOURCE_OTHER if config.source_old_binutils: if source_line and re.fullmatch(".*\.c(?:pp)?:\d+", source_line): line_format = BasicFormat.SOURCE_FILENAME elif source_line and source_line.endswith("():"): line_format = BasicFormat.SOURCE_FUNCTION try: source_line = cxxfilt.demangle( source_line[:-3], external_only=False ) except: pass else: # File names and function names if source_line and source_line[0] != "│": line_format = BasicFormat.SOURCE_FILENAME # Function names if source_line.endswith("():"): line_format = BasicFormat.SOURCE_FUNCTION try: source_line = cxxfilt.demangle( source_line[:-3], external_only=False ) except: pass padding = " " * 7 if config.show_line_numbers else " " * 2 output.append( OutputLine( base=None, fmt2=padding + Text(source_line, line_format), key2=source_line, boring=True, is_data_ref=False, line1=None, line2=None, ) ) key2 = line2.normalized_original if line2 else None boring = False if line_prefix == " ": boring = True elif config.compress and config.compress.same_instr and line_prefix in "irs": boring = True if config.show_line_numbers: if line2 and line2.source_line_num is not None: num_color = ( BasicFormat.SOURCE_LINE_NUM if sym_color == BasicFormat.NONE else sym_color ) num2 = Text(f"{line2.source_line_num:5}", num_color) else: num2 = Text(" " * 5) else: num2 = Text() fmt2 = Text(line_prefix, sym_color) + num2 + " " + (part2 or Text()) output.append( OutputLine( base=part1, fmt2=fmt2, key2=key2, boring=boring, is_data_ref=is_data_ref, line1=line1, line2=line2, ) ) return Diff(lines=output, score=score) def chunk_diff_lines( diff: List[OutputLine], ) -> List[Union[List[OutputLine], OutputLine]]: """Chunk a diff into an alternating list like A B A B ... A, where: * A is a List[OutputLine] of insertions, * B is a single non-insertion OutputLine, with .base != None.""" cur_right: List[OutputLine] = [] chunks: List[Union[List[OutputLine], OutputLine]] = [] for output_line in diff: if output_line.base is not None: chunks.append(cur_right) chunks.append(output_line) cur_right = [] else: cur_right.append(output_line) chunks.append(cur_right) return chunks def compress_matching( li: List[Tuple[OutputLine, ...]], context: int ) -> List[Tuple[OutputLine, ...]]: ret: List[Tuple[OutputLine, ...]] = [] matching_streak: List[Tuple[OutputLine, ...]] = [] context = max(context, 0) def flush_matching() -> None: if len(matching_streak) <= 2 * context + 1: ret.extend(matching_streak) else: ret.extend(matching_streak[:context]) skipped = len(matching_streak) - 2 * context filler = OutputLine( base=Text(f"<{skipped} lines>", BasicFormat.SOURCE_OTHER), fmt2=Text(), key2=None, boring=False, is_data_ref=False, line1=None, line2=None, ) columns = len(matching_streak[0]) ret.append(tuple([filler] * columns)) if context > 0: ret.extend(matching_streak[-context:]) matching_streak.clear() for line in li: if line[0].boring: matching_streak.append(line) else: flush_matching() ret.append(line) flush_matching() return ret def align_diffs( old_diff: Diff, new_diff: Diff, config: Config ) -> Tuple[TableMetadata, List[Tuple[OutputLine, ...]]]: meta: TableMetadata diff_lines: List[Tuple[OutputLine, ...]] padding = " " * 7 if config.show_line_numbers else " " * 2 if config.threeway: meta = TableMetadata( headers=( Text("TARGET"), Text(f"{padding}CURRENT ({new_diff.score})"), Text(f"{padding}PREVIOUS ({old_diff.score})"), ), current_score=new_diff.score, previous_score=old_diff.score, ) old_chunks = chunk_diff_lines(old_diff.lines) new_chunks = chunk_diff_lines(new_diff.lines) diff_lines = [] empty = OutputLine(Text(), Text(), None, True, False, None, None) assert len(old_chunks) == len(new_chunks), "same target" for old_chunk, new_chunk in zip(old_chunks, new_chunks): if isinstance(old_chunk, list): assert isinstance(new_chunk, list) if not old_chunk and not new_chunk: # Most of the time lines sync up without insertions/deletions, # and there's no interdiffing to be done. continue differ = difflib.SequenceMatcher( a=old_chunk, b=new_chunk, autojunk=False ) for (tag, i1, i2, j1, j2) in differ.get_opcodes(): if tag in ["equal", "replace"]: for i, j in zip(range(i1, i2), range(j1, j2)): diff_lines.append((empty, new_chunk[j], old_chunk[i])) if tag in ["insert", "replace"]: for j in range(j1 + i2 - i1, j2): diff_lines.append((empty, new_chunk[j], empty)) if tag in ["delete", "replace"]: for i in range(i1 + j2 - j1, i2): diff_lines.append((empty, empty, old_chunk[i])) else: assert isinstance(new_chunk, OutputLine) # old_chunk.base and new_chunk.base have the same text since # both diffs are based on the same target, but they might # differ in color. Use the new version. diff_lines.append((new_chunk, new_chunk, old_chunk)) diff_lines = [ (base, new, old if old != new else empty) for base, new, old in diff_lines ] else: meta = TableMetadata( headers=( Text("TARGET"), Text(f"{padding}CURRENT ({new_diff.score})"), ), current_score=new_diff.score, previous_score=None, ) diff_lines = [(line, line) for line in new_diff.lines] if config.compress: diff_lines = compress_matching(diff_lines, config.compress.context) return meta, diff_lines def debounced_fs_watch( targets: List[str], outq: "queue.Queue[Optional[float]]", config: Config, project: ProjectSettings, ) -> None: import watchdog.events import watchdog.observers class WatchEventHandler(watchdog.events.FileSystemEventHandler): def __init__( self, queue: "queue.Queue[float]", file_targets: List[str] ) -> None: self.queue = queue self.file_targets = file_targets def on_modified(self, ev: object) -> None: if isinstance(ev, watchdog.events.FileModifiedEvent): self.changed(ev.src_path) def on_moved(self, ev: object) -> None: if isinstance(ev, watchdog.events.FileMovedEvent): self.changed(ev.dest_path) def should_notify(self, path: str) -> bool: for target in self.file_targets: if os.path.normpath(path) == target: return True if config.make and any( path.endswith(suffix) for suffix in project.source_extensions ): return True return False def changed(self, path: str) -> None: if self.should_notify(path): self.queue.put(time.time()) def debounce_thread() -> NoReturn: listenq: "queue.Queue[float]" = queue.Queue() file_targets: List[str] = [] event_handler = WatchEventHandler(listenq, file_targets) observer = watchdog.observers.Observer() observed = set() for target in targets: if os.path.isdir(target): observer.schedule(event_handler, target, recursive=True) else: file_targets.append(os.path.normpath(target)) target = os.path.dirname(target) or "." if target not in observed: observed.add(target) observer.schedule(event_handler, target) observer.start() while True: t = listenq.get() more = True while more: delay = t + DEBOUNCE_DELAY - time.time() if delay > 0: time.sleep(delay) # consume entire queue more = False try: while True: t = listenq.get(block=False) more = True except queue.Empty: pass outq.put(t) th = threading.Thread(target=debounce_thread, daemon=True) th.start() class Display: basedump: str mydump: str last_refresh_key: object config: Config emsg: Optional[str] last_diff_output: Optional[Diff] pending_update: Optional[str] ready_queue: "queue.Queue[None]" watch_queue: "queue.Queue[Optional[float]]" less_proc: "Optional[subprocess.Popen[bytes]]" def __init__(self, basedump: str, mydump: str, config: Config) -> None: self.config = config self.base_lines = process(basedump, config) self.mydump = mydump self.emsg = None self.last_refresh_key = None self.last_diff_output = None def run_diff(self) -> Tuple[str, object]: if self.emsg is not None: return (self.emsg, self.emsg) my_lines = process(self.mydump, self.config) diff_output = do_diff(self.base_lines, my_lines, self.config) last_diff_output = self.last_diff_output or diff_output if self.config.threeway != "base" or not self.last_diff_output: self.last_diff_output = diff_output meta, diff_lines = align_diffs(last_diff_output, diff_output, self.config) diff_lines = diff_lines[self.config.skip_lines :] output = self.config.formatter.table(meta, diff_lines) refresh_key = ( [[col.key2 for col in x[1:]] for x in diff_lines], diff_output.score, ) return (output, refresh_key) def run_less( self, output: str ) -> "Tuple[subprocess.Popen[bytes], subprocess.Popen[bytes]]": # Pipe the output through 'tail' and only then to less, to ensure the # write call doesn't block. ('tail' has to buffer all its input before # it starts writing.) This also means we don't have to deal with pipe # closure errors. buffer_proc = subprocess.Popen( BUFFER_CMD, stdin=subprocess.PIPE, stdout=subprocess.PIPE ) less_proc = subprocess.Popen(LESS_CMD, stdin=buffer_proc.stdout) assert buffer_proc.stdin assert buffer_proc.stdout buffer_proc.stdin.write(output.encode()) buffer_proc.stdin.close() buffer_proc.stdout.close() return (buffer_proc, less_proc) def run_sync(self) -> None: output, _ = self.run_diff() proca, procb = self.run_less(output) procb.wait() proca.wait() def run_async(self, watch_queue: "queue.Queue[Optional[float]]") -> None: self.watch_queue = watch_queue self.ready_queue = queue.Queue() self.pending_update = None output, refresh_key = self.run_diff() self.last_refresh_key = refresh_key dthread = threading.Thread(target=self.display_thread, args=(output,)) dthread.start() self.ready_queue.get() def display_thread(self, initial_output: str) -> None: proca, procb = self.run_less(initial_output) self.less_proc = procb self.ready_queue.put(None) while True: ret = procb.wait() proca.wait() self.less_proc = None if ret != 0: # fix the terminal os.system("tput reset") if ret != 0 and self.pending_update is not None: # killed by program with the intent to refresh output = self.pending_update self.pending_update = None proca, procb = self.run_less(output) self.less_proc = procb self.ready_queue.put(None) else: # terminated by user, or killed self.watch_queue.put(None) self.ready_queue.put(None) break def progress(self, msg: str) -> None: # Write message to top-left corner sys.stdout.write("\x1b7\x1b[1;1f{}\x1b8".format(msg + " ")) sys.stdout.flush() def update(self, text: str, error: bool) -> None: if not error and not self.emsg and text == self.mydump: self.progress("Unchanged. ") return if not error: self.mydump = text self.emsg = None else: self.emsg = text output, refresh_key = self.run_diff() if refresh_key == self.last_refresh_key: self.progress("Unchanged. ") return self.last_refresh_key = refresh_key self.pending_update = output if not self.less_proc: return self.less_proc.kill() self.ready_queue.get() def terminate(self) -> None: if not self.less_proc: return self.less_proc.kill() self.ready_queue.get() def main() -> None: args = parser.parse_args() # Apply project-specific configuration. settings: Dict[str, Any] = {} diff_settings.apply(settings, args) # type: ignore project = create_project_settings(settings) config = create_config(args, project) if config.algorithm == "levenshtein": try: import Levenshtein except ModuleNotFoundError as e: fail(MISSING_PREREQUISITES.format(e.name)) if config.source: try: import cxxfilt except ModuleNotFoundError as e: fail(MISSING_PREREQUISITES.format(e.name)) if config.threeway and not args.watch: fail("Threeway diffing requires -w.") if args.diff_elf_symbol: make_target, basecmd, mycmd = dump_elf( args.start, args.end, args.diff_elf_symbol, config, project ) elif config.diff_obj: make_target, basecmd, mycmd = dump_objfile( args.start, args.end, config, project ) else: make_target, basecmd, mycmd = dump_binary(args.start, args.end, config, project) map_build_target_fn = getattr(diff_settings, "map_build_target", None) if map_build_target_fn: make_target = map_build_target_fn(make_target=make_target) if args.write_asm is not None: mydump = run_objdump(mycmd, config, project) with open(args.write_asm, "w") as f: f.write(mydump) print(f"Wrote assembly to {args.write_asm}.") sys.exit(0) if args.base_asm is not None: with open(args.base_asm) as f: basedump = f.read() else: basedump = run_objdump(basecmd, config, project) mydump = run_objdump(mycmd, config, project) display = Display(basedump, mydump, config) if args.no_pager or args.format in ("html", "json"): print(display.run_diff()[0]) elif not args.watch: display.run_sync() else: if not args.make: yn = input( "Warning: watch-mode (-w) enabled without auto-make (-m). " "You will have to run make manually. Ok? (Y/n) " ) if yn.lower() == "n": return if args.make: watch_sources = None watch_sources_for_target_fn = getattr( diff_settings, "watch_sources_for_target", None ) if watch_sources_for_target_fn: watch_sources = watch_sources_for_target_fn(make_target) watch_sources = watch_sources or project.source_directories if not watch_sources: fail("Missing source_directories config, don't know what to watch.") else: watch_sources = [make_target] q: "queue.Queue[Optional[float]]" = queue.Queue() debounced_fs_watch(watch_sources, q, config, project) display.run_async(q) last_build = 0.0 try: while True: t = q.get() if t is None: break if t < last_build: continue last_build = time.time() if args.make: display.progress("Building...") ret = run_make_capture_output(make_target, project) if ret.returncode != 0: display.update( ret.stderr.decode("utf-8-sig", "replace") or ret.stdout.decode("utf-8-sig", "replace"), error=True, ) continue mydump = run_objdump(mycmd, config, project) display.update(mydump, error=False) except KeyboardInterrupt: display.terminate() if __name__ == "__main__": main()