def test_value_pool_no_default():
test1, test2 = object(), object()
pool = ValuePool(None)
assert pool.index_for(test1) == 0
assert pool.value_at(0) == test1
assert pool.index_for(test2) == 1
assert pool.value_at(1) == test2
def test_value_pool_default():
test = object()
pool = ValuePool(None, default=test)
assert pool.value_at(0) == test
assert pool.index_for(test) == 0
assert pool.index_for(1) == 1
assert pool.index_for(1) == 1
assert pool.value_at(0) == test
assert pool.value_at(1) == 1
def __init__(self, local_names):
self.local_names = local_names
self.locals = ValuePool(None)
for i in local_names:
self.locals.index_for(i)
self.instructions = []
self._stack_depth = 0
self._scope_depth = 0
self.max_local_count = len(local_names)
self.max_stack_depth = 0
self.max_scope_depth = 0
# jump-like instructions
self.jumps = []
# name -> Label
self.labels = {}
self.flags = 0
def __init__(self):
self.int = ValuePool(self, 0)
# don't match -- pushuint is dumb
self.uint = ValuePool(self, 0, lambda v: False)
self.double = ValuePool(self, float('nan'), isnan)
# don't match due to https://bugzilla.mozilla.org/show_bug.cgi?id=628031
self.utf8 = ValuePool(self, "", lambda v: False)
self.namespace = ValuePool(self, ANY_NAMESPACE)
self.nsset = ValuePool(self, "non-existant", lambda v: False)
self.multiname = ValuePool(self, QName("*"))
def test_value_pool_no_default():
test1, test2 = object(), object()
pool = ValuePool(None)
assert pool.index_for(test1) == 0
assert pool.value_at(0) == test1
assert pool.index_for(test2) == 1
assert pool.value_at(1) == test2
def __init__(self, constants=None):
self.constants = constants or ConstantPool()
self.methods = ValuePool(self)
self.metadatas = ValuePool(self)
self.instances = ValuePool(self)
self.classes = ValuePool(self)
self.scripts = ValuePool(self)
self.bodies = ValuePool(self)
def test_value_pool_default():
test = object()
pool = ValuePool(None, default=test)
assert pool.value_at(0) == test
assert pool.index_for(test) == 0
assert pool.index_for(1) == 1
assert pool.index_for(1) == 1
assert pool.value_at(0) == test
assert pool.value_at(1) == 1
def __init__(self, local_names):
self.local_names = local_names
self.locals = ValuePool(None)
for i in local_names:
self.locals.index_for(i)
self.instructions = []
self._stack_depth = 0
self._scope_depth = 0
self.max_local_count = len(local_names)
self.max_stack_depth = 0
self.max_scope_depth = 0
# jump-like instructions
self.jumps = []
# name -> Label
self.labels = {}
self.flags = 0
class CodeAssembler(object):
implements(IConstantPoolWriter)
def __init__(self, local_names):
self.local_names = local_names
self.locals = ValuePool(None)
for i in local_names:
self.locals.index_for(i)
self.instructions = []
self._stack_depth = 0
self._scope_depth = 0
self.max_local_count = len(local_names)
self.max_stack_depth = 0
self.max_scope_depth = 0
# jump-like instructions
self.jumps = []
# name -> Label
self.labels = {}
self.flags = 0
def make_label(self, name):
label = Label(name)
label.stack_depth, label.scope_depth = self.stack_depth, self.scope_depth
return self.labels.setdefault(name, label)
def emit(self, name, *a, **kw):
"""
Emit an instruction, with given arguments.
"""
return self.add_instruction(get_instruction(name)(*a, **kw))
def add_instruction(self, instruction):
"""
Add an instruction to this block.
"""
self.instructions.append(instruction)
instruction.assembler_added(self)
return instruction
def add_instructions(self, instructions):
"""
Iterate over the given argument and add these instructions,
one by one, to this assembler.
"""
for i in instructions:
self.add_instruction(i)
def optimize(self):
"""
Do some not so simple optimizations.
"""
for _ in xrange(2):
jumps = {}
# instructions to remove
remv_inst = set()
# register -> set([prev, curr])
remv_regs = {}
institer = iter(self.instructions)
instructions = [institer.next()]
# First pass - mark anything needed for the second pass.
for newinst in institer:
instructions.append(newinst)
prev, curr = instructions[-2:]
# Gather all jumps by their respective labels.
if curr.jumplike:
jumps.setdefault(curr.labelname, []).append(curr)
S = set((prev, curr))
# Detect if there are any references to this register other than
# the setlocal/getlocal sequence here.
if prev.name in SET_LOCALS and \
curr.name in GET_LOCALS and \
prev.argument == curr.argument:
remv_inst.update(S)
remv_regs[curr.argument] = S
# PyPy-specific optimization: some opcodes have an unnecessary
# StoreResult at the end, so callpropvoid and some setproperty's
# have a pushnull and an unused register afterwards. Stop that.
elif prev.name in ("pushnull", "pushundefined") and \
curr.name in SET_LOCALS:
remv_inst.update(S)
remv_regs[curr.argument] = S
elif curr.name in GET_LOCALS:
if curr.argument in remv_regs:
remv_inst -= remv_regs[curr.argument]
elif curr.name in SET_LOCALS:
# If we have any
remv_regs.pop(curr.argument, None)
elif curr.name == "kill":
# If we're going to remove this register, mark the kill for deletion too.
if curr.argument in remv_regs:
remv_inst.add(curr)
prev = curr
institer = iter(self.instructions)
instructions = [institer.next()]
# Second pass
for newinst in institer:
instructions.append(newinst)
keep_going = True
while keep_going:
prev, curr = instructions[-2:]
test = prev.name, curr.name
# Prevent errors with jumps and lone labels.
if curr.name == "label" and curr.labelname not in jumps:
instructions = instructions[:-1]
# Branch optimizations geared for PyPy.
elif test in BRANCH_OPTIMIZE:
instructions = instructions[:-2]
new = get_instruction(BRANCH_OPTIMIZE[test])(
curr.labelname)
jumps[curr.labelname].remove(curr)
jumps[curr.labelname].append(new)
instructions.append(new)
# Two opcodes in a row that do nothing should be removed.
elif prev.name in GET_LOCALS and curr.name in SET_LOCALS \
and prev.argument == curr.argument:
instructions = instructions[:-2]
# jump then label -> remove the jump.
elif test == ("jump", "label"
) and prev.labelname == curr.labelname:
# Don't remove the label, we may need it for a backref later on.
instructions.pop(-2)
jumps[prev.labelname].remove(prev)
# return after return -> remove the second return.
elif prev.name in ("returnvalue", "returnvoid") and \
curr.name in ("returnvalue", "returnvoid"):
instructions.pop()
# label then jump -> remove both and rename.
elif test == ("label", "jump"):
for jump in jumps[prev.labelname]:
jump.labelname = curr.labelname
jumps[curr.labelname].remove(curr)
jumps[curr.labelname].extend(jumps[prev.labelname])
del jumps[prev.labelname]
instructions = instructions[:-2]
elif curr in remv_inst:
instructions.pop()
else:
keep_going = False
self.instructions = instructions
# Third pass - pack in those registers.
institer = iter(self.instructions)
inst = [institer.next()]
# local_names is the arguments to the method
used_registers = dict((i, i) for i in xrange(len(self.local_names)))
for newinst in institer:
curr = inst[-1]
if curr.name in SET_LOCALS:
index = used_registers.setdefault(curr.argument,
len(used_registers))
instructions[-1] = get_instruction('setlocal')(index)
elif curr.name in GET_LOCALS:
inst[-1] = get_instruction('getlocal')(used_registers.get(
curr.argument, curr.argument))
elif curr.name == "kill":
inst[-1] = get_instruction('kill')(used_registers.get(
curr.argument, curr.argument))
self.numlocals = len(used_registers)
self.instructions = instructions
# ========================================
# STACK DEPTH and SCOPE DEPTH tracking
def get_stack_depth(self):
return self._stack_depth
def set_stack_depth(self, value):
self._stack_depth = value
if value > self.max_stack_depth:
self.max_stack_depth = value
stack_depth = property(get_stack_depth, set_stack_depth)
def get_scope_depth(self):
return self._scope_depth
def set_scope_depth(self, value):
self._scope_depth = value
if value > self.max_scope_depth:
self.max_scope_depth = value
scope_depth = property(get_scope_depth, set_scope_depth)
# ========================================
# LOCAL tracking
@property
def next_free_local(self):
"""
Return the index of the next empty local.
"""
return self.locals.next_free()
def set_local(self, name):
"""
Mark the register named "name" as set and return
the index.
"""
index = self.locals.index_for(name)
if self.local_count > self.max_local_count:
self.max_local_count = self.local_count
return index
def get_local(self, name):
"""
Return the index for the local named "name".
"""
return self.locals.get_index(name)
def kill_local(self, name):
"""
Mark the register named "name" as free and return
the index.
"""
index = self.locals.kill(name)
if self.local_count > self.max_local_count:
self.max_local_count = self.local_count
return index
def has_local(self, name):
"""
Returns True if we have a register named "name" in the current
assembler context.
"""
return name in self.locals
@property
def local_count(self):
"""
The current local count.
"""
return len(self.locals)
def dump_instructions(self, exceptions=[], use_label_names=False):
"""
Dump this assembler's instructions to a string, with the given
"indent" prepended to each line. If "use_label_names" is True,
then the label names will be used when dumping, otherwise
label names will be generated. Label names are not kept in
compiled code, so it makes to set this to False when dumping
parsed code.
"""
# label name => remapped label name
lblmap = {}
# address => [exception, ...]
exc_from = {}
exc_to = {}
for exc in exceptions:
exc_from.setdefault(exc.from_, []).append(exc)
exc_to.setdefault(exc.to_, []).append(exc)
for inst in self.instructions:
inst.assembler_pass1(self)
if inst.label and not use_label_names:
lblmap[inst.label.name] = "L%d" % (len(lblmap) + 1)
dump, offset = [], 0
for inst in self.instructions:
if inst.label:
lblname = inst.label.name
lblname = lblmap.get(lblname, lblname)
if inst.jumplike:
# we're jumping to the label -- get us a mapped label
inst.labelname = lblname
else:
# we're defining a label
dump.append("\n%s:" % (lblname, ))
for exc in exc_from.get(offset, []):
dump.append("<%s %d" % (exc.exc_type, exc.target))
for exc in exc_to.get(offset, []):
dump.append(">%s %d" % (exc.exc_type, exc.target))
dump.append("%d\t%s" % (offset, inst))
offset += len(inst)
return '\n'.join(dump)
def pass1(self):
"""
Do assembler pass 1.
"""
# Pass 1.
for inst in self.instructions:
inst.assembler_pass1(self)
def write_constants(self, pool):
for inst in self.instructions:
pool.write(inst)
def serialize(self):
"""
Serialize this code to a string, and also
resolve any jump offsets.
"""
code = StringIO()
# Pass 2. Generate code.
for inst in self.instructions:
inst.assembler_pass2(self, code.tell())
code.write(inst.serialize())
# Patch up jumps.
for inst in self.jumps:
assert inst in self.instructions
code.seek(inst.address + 1)
code.write(inst.label.relative_offset(inst.address + 4))
return code.getvalue()
@classmethod
def parse(cls, bitstream, abc, constants, local_count):
asm = cls(["_loc%d" % (i, ) for i in xrange(local_count)])
codelen = bitstream.read(U32)
finish = bitstream.tell() + codelen * 8
while bitstream.tell() < finish:
asm.add_instruction(
parse_instruction(bitstream, abc, constants, asm))
return asm
class CodeAssembler(object):
implements(IConstantPoolWriter)
def __init__(self, local_names):
self.local_names = local_names
self.locals = ValuePool(None)
for i in local_names:
self.locals.index_for(i)
self.instructions = []
self._stack_depth = 0
self._scope_depth = 0
self.max_local_count = len(local_names)
self.max_stack_depth = 0
self.max_scope_depth = 0
# jump-like instructions
self.jumps = []
# name -> Label
self.labels = {}
self.flags = 0
def make_label(self, name):
label = Label(name)
label.stack_depth, label.scope_depth = self.stack_depth, self.scope_depth
return self.labels.setdefault(name, label)
def emit(self, name, *a, **kw):
"""
Emit an instruction, with given arguments.
"""
print " ", name, a
return self.add_instruction(get_instruction(name)(*a, **kw))
def add_instruction(self, instruction):
"""
Add an instruction to this block.
"""
self.instructions.append(instruction)
instruction.assembler_added(self)
return instruction
def add_instructions(self, instructions):
"""
Iterate over the given argument and add these instructions,
one by one, to this assembler.
"""
for i in instructions:
self.add_instruction(i)
def optimize(self):
"""
Do some not so simple optimizations.
"""
for _ in xrange(2):
jumps = {}
# instructions to remove
remv_inst = set()
# register -> set([prev, curr])
remv_regs = {}
institer = iter(self.instructions)
instructions = [institer.next()]
# First pass - mark anything needed for the second pass.
for newinst in institer:
instructions.append(newinst)
prev, curr = instructions[-2:]
# Gather all jumps by their respective labels.
if curr.jumplike:
jumps.setdefault(curr.labelname, []).append(curr)
S = set((prev, curr))
# Detect if there are any references to this register other than
# the setlocal/getlocal sequence here.
if prev.name in SET_LOCALS and curr.name in GET_LOCALS and prev.argument == curr.argument:
remv_inst.update(S)
remv_regs[curr.argument] = S
# PyPy-specific optimization: some opcodes have an unnecessary
# StoreResult at the end, so callpropvoid and some setproperty's
# have a pushnull and an unused register afterwards. Stop that.
elif prev.name in ("pushnull", "pushundefined") and curr.name in SET_LOCALS:
remv_inst.update(S)
remv_regs[curr.argument] = S
elif curr.name in GET_LOCALS:
if curr.argument in remv_regs:
remv_inst -= remv_regs[curr.argument]
elif curr.name in SET_LOCALS:
# If we have any
remv_regs.pop(curr.argument, None)
elif curr.name == "kill":
# If we're going to remove this register, mark the kill for deletion too.
if curr.argument in remv_regs:
remv_inst.add(curr)
prev = curr
institer = iter(self.instructions)
instructions = [institer.next()]
# Second pass
for newinst in institer:
instructions.append(newinst)
keep_going = True
while keep_going:
prev, curr = instructions[-2:]
test = prev.name, curr.name
# Prevent errors with jumps and lone labels.
if curr.name == "label" and curr.labelname not in jumps:
instructions = instructions[:-1]
# Branch optimizations geared for PyPy.
elif test in BRANCH_OPTIMIZE:
instructions = instructions[:-2]
new = get_instruction(BRANCH_OPTIMIZE[test])(curr.labelname)
jumps[curr.labelname].remove(curr)
jumps[curr.labelname].append(new)
instructions.append(new)
# Two opcodes in a row that do nothing should be removed.
elif prev.name in GET_LOCALS and curr.name in SET_LOCALS and prev.argument == curr.argument:
instructions = instructions[:-2]
# jump then label -> remove the jump.
elif test == ("jump", "label") and prev.labelname == curr.labelname:
# Don't remove the label, we may need it for a backref later on.
instructions.pop(-2)
jumps[prev.labelname].remove(prev)
# return after return -> remove the second return.
elif prev.name in ("returnvalue", "returnvoid") and curr.name in ("returnvalue", "returnvoid"):
instructions.pop()
# label then jump -> remove both and rename.
elif test == ("label", "jump"):
for jump in jumps[prev.labelname]:
jump.labelname = curr.labelname
jumps[curr.labelname].remove(curr)
jumps[curr.labelname].extend(jumps[prev.labelname])
del jumps[prev.labelname]
instructions = instructions[:-2]
elif curr in remv_inst:
instructions.pop()
else:
keep_going = False
self.instructions = instructions
# Third pass - pack in those registers.
institer = iter(self.instructions)
inst = [institer.next()]
# local_names is the arguments to the method
used_registers = dict((i, i) for i in xrange(len(self.local_names)))
for newinst in institer:
curr = inst[-1]
if curr.name in SET_LOCALS:
index = used_registers.setdefault(curr.argument, len(used_registers))
instructions[-1] = get_instruction("setlocal")(index)
elif curr.name in GET_LOCALS:
inst[-1] = get_instruction("getlocal")(used_registers.get(curr.argument, curr.argument))
elif curr.name == "kill":
inst[-1] = get_instruction("kill")(used_registers.get(curr.argument, curr.argument))
self.numlocals = len(used_registers)
self.instructions = instructions
# ========================================
# STACK DEPTH and SCOPE DEPTH tracking
def get_stack_depth(self):
return self._stack_depth
def set_stack_depth(self, value):
self._stack_depth = value
if value > self.max_stack_depth:
self.max_stack_depth = value
stack_depth = property(get_stack_depth, set_stack_depth)
def get_scope_depth(self):
return self._scope_depth
def set_scope_depth(self, value):
self._scope_depth = value
if value > self.max_scope_depth:
self.max_scope_depth = value
scope_depth = property(get_scope_depth, set_scope_depth)
# ========================================
# LOCAL tracking
@property
def next_free_local(self):
"""
Return the index of the next empty local.
"""
return self.locals.next_free()
def set_local(self, name):
"""
Mark the register named "name" as set and return
the index.
"""
index = self.locals.index_for(name)
if self.local_count > self.max_local_count:
self.max_local_count = self.local_count
return index
def get_local(self, name):
"""
Return the index for the local named "name".
"""
return self.locals.get_index(name)
def kill_local(self, name):
"""
Mark the register named "name" as free and return
the index.
"""
index = self.locals.kill(name)
if self.local_count > self.max_local_count:
self.max_local_count = self.local_count
return index
def has_local(self, name):
"""
Returns True if we have a register named "name" in the current
assembler context.
"""
return name in self.locals
@property
def local_count(self):
"""
The current local count.
"""
return len(self.locals)
def dump_instructions(self, exceptions=[], use_label_names=False):
"""
Dump this assembler's instructions to a string, with the given
"indent" prepended to each line. If "use_label_names" is True,
then the label names will be used when dumping, otherwise
label names will be generated. Label names are not kept in
compiled code, so it makes to set this to False when dumping
parsed code.
"""
# label name => remapped label name
lblmap = {}
# address => [exception, ...]
exc_from = {}
exc_to = {}
for exc in exceptions:
exc_from.setdefault(exc.from_, []).append(exc)
exc_to.setdefault(exc.to_, []).append(exc)
for inst in self.instructions:
inst.assembler_pass1(self)
if inst.label and not use_label_names:
lblmap[inst.label.name] = "L%d" % (len(lblmap) + 1)
dump, offset = [], 0
for inst in self.instructions:
if inst.label:
lblname = inst.label.name
lblname = lblmap.get(lblname, lblname)
if inst.jumplike:
# we're jumping to the label -- get us a mapped label
inst.labelname = lblname
else:
# we're defining a label
dump.append("\n%s:" % (lblname,))
for exc in exc_from.get(offset, []):
dump.append("<%s %d" % (exc.exc_type, exc.target))
for exc in exc_to.get(offset, []):
dump.append(">%s %d" % (exc.exc_type, exc.target))
dump.append("%d\t%s" % (offset, inst))
offset += len(inst)
return "\n".join(dump)
def pass1(self):
"""
Do assembler pass 1.
"""
# Pass 1.
for inst in self.instructions:
inst.assembler_pass1(self)
def write_constants(self, pool):
for inst in self.instructions:
pool.write(inst)
def serialize(self):
"""
Serialize this code to a string, and also
resolve any jump offsets.
"""
code = StringIO()
# Pass 2. Generate code.
for inst in self.instructions:
inst.assembler_pass2(self, code.tell())
code.write(inst.serialize())
# Patch up jumps.
for inst in self.jumps:
assert inst in self.instructions
code.seek(inst.address + 1)
code.write(inst.label.relative_offset(inst.address + 4))
return code.getvalue()
@classmethod
def parse(cls, bitstream, abc, constants, local_count):
asm = cls(["_loc%d" % (i,) for i in xrange(local_count)])
codelen = bitstream.read(U32)
finish = bitstream.tell() + codelen * 8
while bitstream.tell() < finish:
asm.add_instruction(parse_instruction(bitstream, abc, constants, asm))
return asm