luau/tools/lvmexecute_split.py
2023-01-13 12:36:28 -08:00

112 lines
3.6 KiB
Python

#!/usr/bin/python3
# This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
# This code can be used to split lvmexecute.cpp VM switch into separate functions for use as native code generation fallbacks
import sys
import re
input = sys.stdin.readlines()
inst = ""
header = """// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
// This file was generated by 'tools/lvmexecute_split.py' script, do not modify it by hand
#pragma once
#include <stdint.h>
struct lua_State;
struct Closure;
typedef uint32_t Instruction;
typedef struct lua_TValue TValue;
typedef TValue* StkId;
"""
source = """// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
// This code is based on Lua 5.x implementation licensed under MIT License; see lua_LICENSE.txt for details
// This file was generated by 'tools/lvmexecute_split.py' script, do not modify it by hand
#include "Fallbacks.h"
#include "FallbacksProlog.h"
"""
function = ""
signature = ""
includeInsts = ["LOP_NEWCLOSURE", "LOP_NAMECALL", "LOP_FORGPREP", "LOP_GETVARARGS", "LOP_DUPCLOSURE", "LOP_PREPVARARGS", "LOP_BREAK", "LOP_GETGLOBAL", "LOP_SETGLOBAL", "LOP_GETTABLEKS", "LOP_SETTABLEKS"]
state = 0
# parse with the state machine
for line in input:
# find the start of an instruction
if state == 0:
match = re.match("\s+VM_CASE\((LOP_[A-Z_0-9]+)\)", line)
if match:
inst = match[1]
signature = "const Instruction* execute_" + inst + "(lua_State* L, const Instruction* pc, StkId base, TValue* k)"
function = signature + "\n"
function += "{\n"
function += " [[maybe_unused]] Closure* cl = clvalue(L->ci->func);\n"
state = 1
# first line of the instruction which is "{"
elif state == 1:
assert(line == " {\n")
state = 2
# find the end of an instruction
elif state == 2:
# remove jumps back into the native code
if line == "#if LUA_CUSTOM_EXECUTION\n":
state = 3
continue
if line[0] == ' ':
finalline = line[12:-1] + "\n"
else:
finalline = line
finalline = finalline.replace("VM_NEXT();", "return pc;");
finalline = finalline.replace("goto exit;", "return NULL;");
finalline = finalline.replace("return;", "return NULL;");
function += finalline
match = re.match(" }", line)
if match:
# break is not supported
if inst == "LOP_BREAK":
function = "const Instruction* execute_" + inst + "(lua_State* L, const Instruction* pc, StkId base, TValue* k)\n"
function += "{\n LUAU_ASSERT(!\"Unsupported deprecated opcode\");\n LUAU_UNREACHABLE();\n}\n"
# handle fallthrough
elif inst == "LOP_NAMECALL":
function = function[:-len(finalline)]
function += " return pc;\n}\n"
if inst in includeInsts:
header += signature + ";\n"
source += function + "\n"
state = 0
# skip LUA_CUSTOM_EXECUTION code blocks
elif state == 3:
if line == "#endif\n":
state = 4
continue
# skip extra line
elif state == 4:
state = 2
# make sure we found the ending
assert(state == 0)
with open("Fallbacks.h", "w") as fp:
fp.writelines(header)
with open("Fallbacks.cpp", "w") as fp:
fp.writelines(source)