cpython/Tools/cases_generator/target_generator.py
Ken Jin 359c7dde3b
gh-129989: Properly disable tailcall interp in configure (GH-129991)
Co-authored-by: Zanie Blue <contact@zanie.dev>
2025-02-16 03:01:24 +08:00

94 lines
2.9 KiB
Python

"""Generate targets for computed goto dispatch
Reads the instruction definitions from bytecodes.c.
Writes the table to opcode_targets.h by default.
"""
import argparse
from analyzer import (
Analysis,
analyze_files,
)
from generators_common import (
DEFAULT_INPUT,
ROOT,
)
from tier1_generator import UNKNOWN_OPCODE_HANDLER
from cwriter import CWriter
DEFAULT_OUTPUT = ROOT / "Python/opcode_targets.h"
def write_opcode_targets(analysis: Analysis, out: CWriter) -> None:
"""Write header file that defines the jump target table"""
targets = ["&&_unknown_opcode,\n"] * 256
for name, op in analysis.opmap.items():
if op < 256:
targets[op] = f"&&TARGET_{name},\n"
out.emit("#if !Py_TAIL_CALL_INTERP\n")
out.emit("static void *opcode_targets[256] = {\n")
for target in targets:
out.emit(target)
out.emit("};\n")
out.emit("#else /* Py_TAIL_CALL_INTERP */\n")
def function_proto(name: str) -> str:
return f"Py_PRESERVE_NONE_CC static PyObject *_TAIL_CALL_{name}(TAIL_CALL_PARAMS)"
def write_tailcall_dispatch_table(analysis: Analysis, out: CWriter) -> None:
out.emit("static py_tail_call_funcptr INSTRUCTION_TABLE[256];\n")
out.emit("\n")
# Emit function prototypes for labels.
for name in analysis.labels:
out.emit(f"{function_proto(name)};\n")
out.emit("\n")
# Emit function prototypes for opcode handlers.
for name in sorted(analysis.instructions.keys()):
out.emit(f"{function_proto(name)};\n")
out.emit("\n")
# Emit unknown opcode handler.
out.emit(function_proto("UNKNOWN_OPCODE"))
out.emit(" {\n")
out.emit("int opcode = next_instr->op.code;\n")
out.emit(UNKNOWN_OPCODE_HANDLER)
out.emit("}\n")
out.emit("\n")
# Emit the dispatch table.
out.emit("static py_tail_call_funcptr INSTRUCTION_TABLE[256] = {\n")
for name in sorted(analysis.instructions.keys()):
out.emit(f"[{name}] = _TAIL_CALL_{name},\n")
named_values = analysis.opmap.values()
for rest in range(256):
if rest not in named_values:
out.emit(f"[{rest}] = _TAIL_CALL_UNKNOWN_OPCODE,\n")
out.emit("};\n")
outfile.write("#endif /* Py_TAIL_CALL_INTERP */\n")
arg_parser = argparse.ArgumentParser(
description="Generate the file with dispatch targets.",
formatter_class=argparse.ArgumentDefaultsHelpFormatter,
)
arg_parser.add_argument(
"-o", "--output", type=str, help="Generated code", default=DEFAULT_OUTPUT
)
arg_parser.add_argument(
"input", nargs=argparse.REMAINDER, help="Instruction definition file(s)"
)
if __name__ == "__main__":
args = arg_parser.parse_args()
if len(args.input) == 0:
args.input.append(DEFAULT_INPUT)
data = analyze_files(args.input)
with open(args.output, "w") as outfile:
out = CWriter(outfile, 0, False)
write_opcode_targets(data, out)
write_tailcall_dispatch_table(data, out)