1#!/usr/bin/env python3 2# 3# Copyright (C) 2018 The Android Open Source Project 4# 5# Licensed under the Apache License, Version 2.0 (the "License"); 6# you may not use this file except in compliance with the License. 7# You may obtain a copy of the License at 8# 9# http://www.apache.org/licenses/LICENSE-2.0 10# 11# Unless required by applicable law or agreed to in writing, software 12# distributed under the License is distributed on an "AS IS" BASIS, 13# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14# See the License for the specific language governing permissions and 15# limitations under the License. 16 17# This script looks through compiled object file (stored human readable text), 18# and looks for the compile-time constants (added through custom "asm" block). 19# For example: .ascii ">>OBJECT_ALIGNMENT_MASK $7 $0<<" 20# 21# It will transform each such line to #define which is usabe in assembly code. 22# For example: #define OBJECT_ALIGNMENT_MASK 0x7 23# 24# Usage: make_header.py out/soong/.intermediates/.../asm_defines.o 25# 26 27import argparse 28import re 29import sys 30 31def convert(input): 32 """Find all defines in the compiler generated assembly and convert them to #define pragmas""" 33 34 asm_define_re = re.compile(r'">>(\w+) (?:\$|#)?([-0-9]+) (?:\$|#)?(0|1)<<"') 35 asm_defines = asm_define_re.findall(input) 36 if not asm_defines: 37 raise RuntimeError("Failed to find any asm defines in the input") 38 39 # Convert the found constants to #define pragmas. 40 # In case the C++ compiler decides to reorder the AsmDefinesFor_${name} functions, 41 # we don't want the order of the .h file to change from one compilation to another. 42 # Sorting ensures deterministic order of the #defines. 43 output = [] 44 for name, value, negative_value in sorted(asm_defines): 45 value = int(value) 46 if value < 0 and negative_value == "0": 47 # Overflow - uint64_t constant was pretty printed as negative value. 48 value += 2 ** 64 # Python will use arbitrary precision arithmetic. 49 output.append("#define {0} {1:#x}".format(name, value)) 50 return "\n".join(output) 51 52if __name__ == "__main__": 53 parser = argparse.ArgumentParser() 54 parser.add_argument('input', help="Object file as text") 55 args = parser.parse_args() 56 print(convert(open(args.input, "r").read())) 57