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refactor asm module parsing code into separate file
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@kripken
kripken committed Aug 2, 2013
1 parent 20f8345 commit ad11d72
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268 changes: 2 additions & 266 deletions emlink.py
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Expand Up @@ -6,9 +6,9 @@
See https://github.com/kripken/emscripten/wiki/Linking
'''

import os, subprocess, sys, re
import os, subprocess, sys
from tools import shared
from tools import js_optimizer
from tools.asm_module import AsmModule

try:
me, main, side, out = sys.argv[:4]
Expand All @@ -22,270 +22,6 @@

shared.try_delete(out)

class AsmModule():
def __init__(self, filename):
self.filename = filename
self.js = open(filename).read()

self.start_asm = self.js.find(js_optimizer.start_asm_marker)
self.start_funcs = self.js.find(js_optimizer.start_funcs_marker)
self.end_funcs = self.js.rfind(js_optimizer.end_funcs_marker)
self.end_asm = self.js.rfind(js_optimizer.end_asm_marker)

# pre
self.pre_js = self.js[:self.start_asm]

# heap initializer
self.staticbump = int(re.search(shared.JS.memory_staticbump_pattern, self.pre_js).group(1))
if self.staticbump:
self.mem_init_js = re.search(shared.JS.memory_initializer_pattern, self.pre_js).group(0)

# global initializers
global_inits = re.search(shared.JS.global_initializers_pattern, self.pre_js)
if global_inits:
self.global_inits_js = global_inits.group(0)
self.global_inits = map(lambda init: init.split('{')[2][1:].split('(')[0], global_inits.groups(0)[0].split(','))
else:
self.global_inits_js = ''
self.global_inits = []

# imports (and global variables)
first_var = self.js.find('var ', self.js.find('var ', self.start_asm)+4)
self.pre_imports_js = self.js[self.start_asm:first_var]
self.imports_js = self.js[first_var:self.start_funcs]
self.imports = {}
for imp in js_optimizer.import_sig.finditer(self.imports_js):
key, value = imp.group(0).split('var ')[1][:-1].split('=', 1)
self.imports[key.strip()] = value.strip()
#print >> sys.stderr, 'imports', self.imports

# funcs
self.funcs_js = self.js[self.start_funcs:self.end_funcs]
self.funcs = set([m.group(2) for m in js_optimizer.func_sig.finditer(self.funcs_js)])
#print 'funcs', self.funcs

# tables and exports
post_js = self.js[self.end_funcs:self.end_asm]
ret = post_js.find('return')
self.tables_js = post_js[:ret]
self.exports_js = post_js[ret:]
self.tables = self.parse_tables(self.tables_js)
self.exports = set([export.strip() for export in self.exports_js[self.exports_js.find('{')+1:self.exports_js.find('}')].split(',')])

# post
self.post_js = self.js[self.end_asm:]
self.sendings = {}
for sending in [sending.strip() for sending in self.post_js[self.post_js.find('}, { ')+5:self.post_js.find(' }, buffer);')].split(',')]:
colon = sending.find(':')
self.sendings[sending[:colon].replace('"', '')] = sending[colon+1:].strip()
self.module_defs = set(re.findall('var [\w\d_$]+ = Module\["[\w\d_$]+"\] = asm\["[\w\d_$]+"\];\n', self.post_js))

def relocate_into(self, main):
# heap initializer
if self.staticbump > 0:
new_mem_init = self.mem_init_js[:self.mem_init_js.rfind(', ')] + ', Runtime.GLOBAL_BASE+%d)' % main.staticbump
main.pre_js = re.sub(shared.JS.memory_staticbump_pattern, 'STATICTOP = STATIC_BASE + %d;\n' % (main.staticbump + side.staticbump) + new_mem_init, main.pre_js, count=1)

# Find function name replacements TODO: do not rename duplicate names with duplicate contents, just merge them
replacements = {}
for func in self.funcs:
rep = func
while rep in main.funcs:
rep += '_'
replacements[func] = rep
#print >> sys.stderr, 'replacements:', replacements

# sendings: add invokes for new tables
all_sendings = main.sendings
added_sending = False
for table in self.tables:
if table not in main.tables:
sig = table[table.rfind('_')+1:]
all_sendings['invoke_%s' % sig] = shared.JS.make_invoke(sig, named=False)
added_sending = True

# imports
all_imports = main.imports
for key, value in self.imports.iteritems():
if key in self.funcs or key in main.funcs: continue # external function in one module, implemented in the other
value_concrete = '.' not in value # env.key means it is an import, an external value, and not a concrete one
main_value = main.imports.get(key)
main_value_concrete = main_value and '.' not in main_value
if value_concrete and main_value_concrete: continue # standard global var
if not main_value or value_concrete:
if '+' in value:
# relocate
value = value.replace('(', '').replace(')', '').replace('| 0', '').replace('|0', '').replace(' ', '')
left, right = value.split('+')
assert left == 'H_BASE'
value = str(main.staticbump + int(right))
all_imports[key] = value
if (value_concrete or main_value_concrete) and key in all_sendings:
del all_sendings[key] # import of external value no longer needed
main.imports_js = '\n'.join(['var %s = %s;' % (key, value) for key, value in all_imports.iteritems()]) + '\n'

# check for undefined references to global variables
def check_import(key, value):
if value.startswith('+') or value.endswith('|0'): # ignore functions
if key not in all_sendings:
print >> sys.stderr, 'warning: external variable %s is still not defined after linking' % key
all_sendings[key] = '0'
for key, value in all_imports.iteritems(): check_import(key, value)

if added_sending:
sendings_js = ', '.join(['%s: %s' % (key, value) for key, value in all_sendings.iteritems()])
sendings_start = main.post_js.find('}, { ')+5
sendings_end = main.post_js.find(' }, buffer);')
main.post_js = main.post_js[:sendings_start] + sendings_js + main.post_js[sendings_end:]

# tables
f_bases = {}
f_sizes = {}
for table, data in self.tables.iteritems():
main.tables[table] = self.merge_tables(table, main.tables.get(table), data, replacements, f_bases, f_sizes)
main.combine_tables()
#print >> sys.stderr, 'f bases', f_bases

# relocate
temp = shared.Building.js_optimizer(self.filename, ['asm', 'relocate', 'last'], extra_info={
'replacements': replacements,
'fBases': f_bases,
'hBase': main.staticbump
})
#print >> sys.stderr, 'relocated side into', temp
relocated_funcs = AsmModule(temp)
shared.try_delete(temp)
main.extra_funcs_js = relocated_funcs.funcs_js.replace(js_optimizer.start_funcs_marker, '\n')

# update function table uses
ft_marker = 'FUNCTION_TABLE_'

def update_fts(what):
updates = []
i = 1 # avoid seeing marker in recursion
while 1:
i = what.find(ft_marker, i)
if i < 0: break;
start = i
end = what.find('[', start)
table = what[i:end]
if table not in f_sizes:
# table was not modified
i += len(ft_marker)
continue
nesting = 1
while nesting > 0:
next = what.find(']', end+1)
nesting -= 1
nesting += what.count('[', end+1, next)
end = next
assert end > 0
mask = what.rfind('&', start, end)
assert mask > 0 and end - mask <= 13
fixed = update_fts(what[start:mask+1] + str(f_sizes[table]-1) + ']')
updates.append((start, end, fixed))
i = end # additional function table uses were done by recursion
# apply updates
if len(updates) == 0: return what
parts = []
so_far = 0
for i in range(len(updates)):
start, end, fixed = updates[i]
parts.append(what[so_far:start])
parts.append(fixed)
so_far = end+1
parts.append(what[so_far:])
return ''.join(parts)

main.funcs_js = update_fts(main.funcs_js)
main.extra_funcs_js = update_fts(main.extra_funcs_js)

# global initializers
if self.global_inits:
my_global_inits = map(lambda init: replacements[init] if init in replacements else init, self.global_inits)
all_global_inits = map(lambda init: '{ func: function() { %s() } }' % init, main.global_inits + my_global_inits)
all_global_inits_js = '/* global initializers */ __ATINIT__.push(' + ','.join(all_global_inits) + ');'
if main.global_inits:
target = main.global_inits_js
else:
target = '// === Body ===\n'
all_global_inits_js = target + all_global_inits_js
main.pre_js = main.pre_js.replace(target, all_global_inits_js)

# exports
def rep_exp(export):
key, value = export.split(':')
if key in replacements:
repped = replacements[key]
return repped + ': ' + repped
return export
my_exports = map(rep_exp, self.exports)
exports = main.exports.union(my_exports)
main.exports_js = 'return {' + ','.join(list(exports)) + '};\n})\n'

# post
def rep_def(deff):
key = deff.split(' ')[1]
if key in replacements:
rep = replacements[key]
return 'var %s = Module["%s"] = asm["%s"];\n' % (rep, rep, rep)
return deff
my_module_defs = map(rep_def, self.module_defs)
new_module_defs = set(my_module_defs).difference(main.module_defs)
if len(new_module_defs) > 0:
position = main.post_js.find('Runtime.') # Runtime is the start of the hardcoded ones
main.post_js = main.post_js[:position] + ''.join(list(new_module_defs)) + '\n' + main.post_js[position:]

def write(self, out):
f = open(out, 'w')
f.write(self.pre_js)
f.write(self.pre_imports_js)
f.write(self.imports_js)
f.write(self.funcs_js)
f.write(self.extra_funcs_js)
f.write(self.tables_js)
f.write(self.exports_js)
f.write(self.post_js)
f.close()

# Utilities

def parse_tables(self, js):
tables = {}
parts = js.split(';')
for part in parts:
if '=' not in part: continue
part = part.split('var ')[1]
name, data = part.split(' = ')
tables[name] = data
return tables

def merge_tables(self, table, main, side, replacements, f_bases, f_sizes):
sig = table.split('_')[-1]
side = side[1:-1].split(',')
side = map(lambda f: replacements[f] if f in replacements else f, side)
if not main:
f_bases[sig] = 0
f_sizes[table] = len(side)
return '[' + ','.join(side) + ']'
main = main[1:-1].split(',')
# TODO: handle non-aliasing case too
assert len(main) % 2 == 0
f_bases[sig] = len(main)
ret = main + side
size = 2
while size < len(ret): size *= 2
aborter = ret[1] # we can assume odd indexes have an aborting function with the right signature
ret = ret + [aborter]*(size - len(ret))
assert len(ret) == size
f_sizes[table] = size
return '[' + ','.join(ret) + ']'

def combine_tables(self):
self.tables_js = '// EMSCRIPTEN_END_FUNCS\n'
for table, data in self.tables.iteritems():
self.tables_js += 'var %s = %s;\n' % (table, data)

main = AsmModule(main)
side = AsmModule(side)

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