def analyze_loop(settings, code, index):
instr = code[index]
if not (instr[0] == byteplay.FOR_ITER and
(index >= 2 and code[index - 2][0] == byteplay.GET_ITER)):
return 0
# Now we found GET_ITER and FOR_ITER instructions
# Try to find SETUP_LOOP
for rel_index in orig_xrange(index - 3, -1, -1):
if code[rel_index][0] == byteplay.SETUP_LOOP:
setup_index = rel_index
break
else:
return 0
# Try to find JUMP_ABSOLUTE and POP_BLOCK by label from FOR_ITER
pop_block_label = instr[1]
for rel_index in orig_xrange(index + 1, len(code) - 1):
if code[rel_index][0] is pop_block_label:
pop_block_index = rel_index + 1
break
else:
return 0
if not (code[pop_block_index - 2][0] == byteplay.JUMP_ABSOLUTE
and code[pop_block_index - 2][1] is code[index - 1][0]
and code[pop_block_index][0] == byteplay.POP_BLOCK):
return 0
# It's busy to check POP_BLOCK instruction existence to
# distinguish real for-loops from a list comprehensions
# Try to find marker of current line's number
for rel_index in orig_xrange(setup_index - 1, -1, -1):
if code[rel_index][0] == byteplay.SetLineno:
head_lineno = code[rel_index][1]
break
else:
head_lineno = None
head = code[setup_index + 1:index - 2]
body = code[index + 1:pop_block_index - 2]
# Don't forget that "else_body" loop part is also exists
settings['head_lineno'] = head_lineno
try:
state = recompiler.recompile_body(settings, body)
except recompiler.RecompileError as err:
if settings['profile']:
profiler.exc(settings, 'Recompilation failed', err)
return 0
# Insert head_handler right before GET_ITER instruction
head_hook = hook.create_head_hook(state, pop_block_label)
code[index - 2:index - 2] = head_hook
if settings['profile']:
profiler.note(settings, 'Recompilation succeeded')
# Return length of analyzed code
return len(head_hook)
def check_iterable(settings, iterable):
if not isinstance(iterable, (xrange, CPMRange)):
raise TypeError(
'Iterator has type %s instead of type "xrange"' % type(iterable)
)
iters_count = iterable.__len__()
if iters_count <= settings['iters_limit']:
if settings['profile']:
profiler.note(settings,
'Skipped optimization of %s iterations' % iters_count)
return None
start = iterable[0]
step = iterable[1] - start
last = iterable[-1]
return start, step, iters_count, last
def check_iterable(settings, iterable):
if not isinstance(iterable, (xrange, CPMRange)):
raise TypeError('Iterator has type %s instead of type "xrange"' %
type(iterable))
iters_count = iterable.__len__()
if iters_count <= settings['iters_limit']:
if settings['profile']:
profiler.note(
settings,
'Skipped optimization of %s iterations' % iters_count)
return None
start = iterable[0]
step = iterable[1] - start
last = iterable[-1]
return start, step, iters_count, last
def analyze_loop(settings, code, index):
instr = code[index]
if not (
instr[0] == byteplay.FOR_ITER and
(index >= 2 and code[index - 2][0] == byteplay.GET_ITER)
):
return 0
# Now we found GET_ITER and FOR_ITER instructions
# Try to find SETUP_LOOP
for rel_index in orig_xrange(index - 3, -1, -1):
if code[rel_index][0] == byteplay.SETUP_LOOP:
setup_index = rel_index
break
else:
return 0
# Try to find JUMP_ABSOLUTE and POP_BLOCK by label from FOR_ITER
pop_block_label = instr[1]
for rel_index in orig_xrange(index + 1, len(code) - 1):
if code[rel_index][0] is pop_block_label:
pop_block_index = rel_index + 1
break
else:
return 0
if not (
code[pop_block_index - 2][0] == byteplay.JUMP_ABSOLUTE and
code[pop_block_index - 2][1] is code[index - 1][0] and
code[pop_block_index][0] == byteplay.POP_BLOCK
):
return 0
# It's busy to check POP_BLOCK instruction existence to
# distinguish real for-loops from a list comprehensions
# Try to find marker of current line's number
for rel_index in orig_xrange(setup_index - 1, -1, -1):
if code[rel_index][0] == byteplay.SetLineno:
head_lineno = code[rel_index][1]
break
else:
head_lineno = None
head = code[setup_index + 1:index - 2]
body = code[index + 1:pop_block_index - 2]
# Don't forget that "else_body" loop part is also exists
settings['head_lineno'] = head_lineno
try:
state = recompiler.recompile_body(settings, body)
except recompiler.RecompileError as err:
if settings['profile']:
profiler.exc(settings, 'Recompilation failed', err)
return 0
# Insert head_handler right before GET_ITER instruction
head_hook = hook.create_head_hook(state, pop_block_label)
code[index - 2:index - 2] = head_hook
if settings['profile']:
profiler.note(settings, 'Recompilation succeeded')
# Return length of analyzed code
return len(head_hook)
