blob: 3ea0d9a16575da3d672fc7faa7237d24a49363c4 [file] [log] [blame]
#!/usr/bin/env python3
#
# Copyright (C) 2018 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# This script looks through compiled object file (stored human readable text),
# and looks for the compile-time constants (added through custom "asm" block).
# For example: .ascii ">>OBJECT_ALIGNMENT_MASK $7 $0<<"
#
# It will transform each such line to #define which is usabe in assembly code.
# For example: #define OBJECT_ALIGNMENT_MASK 0x7
#
# Usage: make_header.py out/soong/.intermediates/.../asm_defines.o
#
import argparse
import re
import sys
def convert(input):
"""Find all defines in the compiler generated assembly and convert them to #define pragmas"""
asm_define_re = re.compile(r'">>(\w+) (?:\$|#)?([-0-9]+) (?:\$|#)?(0|1)<<"')
asm_defines = asm_define_re.findall(input)
if not asm_defines:
raise RuntimeError("Failed to find any asm defines in the input")
# Convert the found constants to #define pragmas.
# In case the C++ compiler decides to reorder the AsmDefinesFor_${name} functions,
# we don't want the order of the .h file to change from one compilation to another.
# Sorting ensures deterministic order of the #defines.
output = []
for name, value, negative_value in sorted(asm_defines):
value = int(value)
if value < 0 and negative_value == "0":
# Overflow - uint64_t constant was pretty printed as negative value.
value += 2 ** 64 # Python will use arbitrary precision arithmetic.
output.append("#define {0} {1:#x}".format(name, value))
return "\n".join(output)
if __name__ == "__main__":
parser = argparse.ArgumentParser()
parser.add_argument('input', help="Object file as text")
args = parser.parse_args()
print(convert(open(args.input, "r").read()))