08e5594cf3
* load_const and load_fast aren't families for now * Don't decref unmoved names * Modernize GET_ANEXT * Modernize GET_AWAITABLE * Modernize ASYNC_GEN_WRAP * Modernize YIELD_VALUE * Modernize POP_EXCEPT (in more than one way) * Modernize PREP_RERAISE_STAR * Modernize LOAD_ASSERTION_ERROR * Modernize LOAD_BUILD_CLASS * Modernize STORE_NAME * Modernize LOAD_NAME * Modernize LOAD_CLASSDEREF * Modernize LOAD_DEREF * Modernize STORE_DEREF * Modernize COPY_FREE_VARS (mark it as done) * Modernize LIST_TO_TUPLE * Modernize LIST_EXTEND * Modernize SET_UPDATE * Modernize SETUP_ANNOTATIONS * Modernize DICT_UPDATE * Modernize DICT_MERGE * Modernize MAP_ADD * Modernize IS_OP * Modernize CONTAINS_OP * Modernize CHECK_EXC_MATCH * Modernize IMPORT_NAME * Modernize IMPORT_STAR * Modernize IMPORT_FROM * Modernize JUMP_FORWARD (mark it as done) * Modernize JUMP_BACKWARD (mark it as done) |
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| .. | ||
| generate_cases.py | ||
| lexer.py | ||
| parser.py | ||
| plexer.py | ||
| README.md | ||
Tooling to generate interpreters
What's currently here:
lexer.py: lexer for C, originally written by Mark Shannonplexer.py: OO interface on top of lexer.py; main class:PLexerparser.py: Parser for instruction definition DSL; main classParsergenerate_cases.py: driver script to readPython/bytecodes.cand writePython/generated_cases.c.h
The DSL for the instruction definitions in Python/bytecodes.c is described
here.
Note that there is some dummy C code at the top and bottom of the file
to fool text editors like VS Code into believing this is valid C code.
A bit about the parser
The parser class uses a pretty standard recursive descent scheme,
but with unlimited backtracking.
The PLexer class tokenizes the entire input before parsing starts.
We do not run the C preprocessor.
Each parsing method returns either an AST node (a Node instance)
or None, or raises SyntaxError (showing the error in the C source).
Most parsing methods are decorated with @contextual, which automatically
resets the tokenizer input position when None is returned.
Parsing methods may also raise SyntaxError, which is irrecoverable.
When a parsing method returns None, it is possible that after backtracking
a different parsing method returns a valid AST.
Neither the lexer nor the parsers are complete or fully correct.
Most known issues are tersely indicated by # TODO: comments.
We plan to fix issues as they become relevant.