refactor asm module parsing code into separate file

1 files changed, 270 insertions, 0 deletions

diff --git a/tools/asm_module.py b/tools/asm_module.py
new file mode 100644
index 00000000..e3fc9a76
--- /dev/null
+++ b/tools/asm_module.py
@@ -0,0 +1,270 @@
+
+import sys, re
+
+import shared, js_optimizer
+
+
+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 + self.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)
+