blob: 9cd6b52f099505fbd1c935cb8774f456c70f783e [file] [log] [blame]
#!/usr/bin/env python
# Script that tries to find how much stack space each function in an
# object is using.
#
# Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
#
# This file may be distributed under the terms of the GNU GPLv3 license.
# Usage:
# objdump -m i386 -M i8086 -M suffix -d out/rom16.o | tools/checkstack.py
import sys
import re
#IGNORE = ['screenc', 'bvprintf']
IGNORE = ['screenc']
# Find out maximum stack usage for a function
def calcmaxstack(funcs, func):
info = funcs[func]
if func.split('.')[0] in IGNORE:
# Function is hardcoded to report 0 stack usage
info[1] = 0
return
# Find max of all nested calls.
max = info[0]
for addr, callfname, usage in info[2]:
callinfo = funcs[callfname]
if callinfo[1] is None:
calcmaxstack(funcs, callfname)
totusage = usage + callinfo[1]
if totusage > max:
max = totusage
info[1] = max
hex_s = r'[0-9a-f]+'
re_func = re.compile(r'^' + hex_s + r' <(?P<func>.*)>:$')
re_asm = re.compile(
r'^[ ]*(?P<addr>' + hex_s + r'):\t.*\t'
r'(?P<insn>[a-z0-9]+ [^<]*)( <(?P<ref>.*)>)?$')
re_usestack = re.compile(
r'^(push.*)|(sub.* [$](?P<num>0x' + hex_s + r'),%esp)$')
def calc():
# funcs = {funcname: [basicstackusage, maxstackusage
# , [(addr, callfname, stackusage), ...]] }
funcs = {}
cur = None
atstart = 0
stackusage = 0
# Parse input lines
for line in sys.stdin.readlines():
m = re_func.match(line)
if m is not None:
# Found function
cur = [0, None, []]
funcs[m.group('func')] = cur
stackusage = 0
atstart = 1
continue
m = re_asm.match(line)
if m is not None:
insn = m.group('insn')
im = re_usestack.match(insn)
if im is not None:
if insn[:4] == 'push':
stackusage += 4
continue
stackusage += int(im.group('num'), 16)
if atstart:
cur[0] = stackusage
atstart = 0
ref = m.group('ref')
if ref is not None and '+' not in ref:
if insn[:1] == 'j':
# Tail call
stackusage = 0
elif insn[:4] == 'call':
stackusage += 4
else:
print "unknown call", ref
cur[2].append((m.group('addr'), ref, stackusage))
# Reset stack usage to preamble usage
stackusage = cur[0]
continue
#print "other", repr(line)
# Calculate maxstackusage
for func, info in funcs.items():
if info[1] is not None:
continue
calcmaxstack(funcs, func)
# Show all functions
funcnames = funcs.keys()
funcnames.sort()
for func in funcnames:
basicusage, maxusage, calls = funcs[func]
if maxusage == 0:
continue
print "\n%s[%d,%d]:" % (func, basicusage, maxusage)
for addr, callfname, stackusage in calls:
callinfo = funcs[callfname]
print " %04s:%-30s[%d+%d,%d]" % (
addr, callfname, stackusage, callinfo[0], stackusage+callinfo[1])
def main():
calc()
if __name__ == '__main__':
main()