def transform_dictionary_comprehension(builder: IRBuilder, o: DictionaryComprehension) -> Value:
d = builder.primitive_op(new_dict_op, [], o.line)
loop_params = list(zip(o.indices, o.sequences, o.condlists))
def gen_inner_stmts() -> None:
k = builder.accept(o.key)
v = builder.accept(o.value)
builder.primitive_op(dict_set_item_op, [d, k, v], o.line)
comprehension_helper(builder, loop_params, gen_inner_stmts, o.line)
return d
def transform_set_comprehension(builder: IRBuilder, o: SetComprehension) -> Value:
gen = o.generator
set_ops = builder.primitive_op(new_set_op, [], o.line)
loop_params = list(zip(gen.indices, gen.sequences, gen.condlists))
def gen_inner_stmts() -> None:
e = builder.accept(gen.left_expr)
builder.primitive_op(set_add_op, [set_ops, e], o.line)
comprehension_helper(builder, loop_params, gen_inner_stmts, o.line)
return set_ops
def transform_dictionary_comprehension(builder: IRBuilder, o: DictionaryComprehension) -> Value:
if any(o.is_async):
builder.error('async comprehensions are unimplemented', o.line)
d = builder.call_c(dict_new_op, [], o.line)
loop_params = list(zip(o.indices, o.sequences, o.condlists))
def gen_inner_stmts() -> None:
k = builder.accept(o.key)
v = builder.accept(o.value)
builder.call_c(dict_set_item_op, [d, k, v], o.line)
comprehension_helper(builder, loop_params, gen_inner_stmts, o.line)
return d
def translate_next_call(builder: IRBuilder, expr: CallExpr,
callee: RefExpr) -> Optional[Value]:
"""Special case for calling next() on a generator expression, an
idiom that shows up some in mypy.
For example, next(x for x in l if x.id == 12, None) will
generate code that searches l for an element where x.id == 12
and produce the first such object, or None if no such element
exists.
"""
if not (expr.arg_kinds in ([ARG_POS], [ARG_POS, ARG_POS])
and isinstance(expr.args[0], GeneratorExpr)):
return None
gen = expr.args[0]
retval = Register(builder.node_type(expr))
default_val = None
if len(expr.args) > 1:
default_val = builder.accept(expr.args[1])
exit_block = BasicBlock()
def gen_inner_stmts() -> None:
# next takes the first element of the generator, so if
# something gets produced, we are done.
builder.assign(retval, builder.accept(gen.left_expr),
gen.left_expr.line)
builder.goto(exit_block)
loop_params = list(zip(gen.indices, gen.sequences, gen.condlists))
comprehension_helper(builder, loop_params, gen_inner_stmts, gen.line)
# Now we need the case for when nothing got hit. If there was
# a default value, we produce it, and otherwise we raise
# StopIteration.
if default_val:
builder.assign(retval, default_val, gen.left_expr.line)
builder.goto(exit_block)
else:
builder.add(
RaiseStandardError(RaiseStandardError.STOP_ITERATION, None,
expr.line))
builder.add(Unreachable())
builder.activate_block(exit_block)
return retval
def any_all_helper(builder: IRBuilder,
gen: GeneratorExpr,
initial_value: Callable[[], Value],
modify: Callable[[Value], Value],
new_value: Callable[[], Value]) -> Value:
retval = Register(bool_rprimitive)
builder.assign(retval, initial_value(), -1)
loop_params = list(zip(gen.indices, gen.sequences, gen.condlists))
true_block, false_block, exit_block = BasicBlock(), BasicBlock(), BasicBlock()
def gen_inner_stmts() -> None:
comparison = modify(builder.accept(gen.left_expr))
builder.add_bool_branch(comparison, true_block, false_block)
builder.activate_block(true_block)
builder.assign(retval, new_value(), -1)
builder.goto(exit_block)
builder.activate_block(false_block)
comprehension_helper(builder, loop_params, gen_inner_stmts, gen.line)
builder.goto_and_activate(exit_block)
return retval
def translate_sum_call(builder: IRBuilder, expr: CallExpr,
callee: RefExpr) -> Optional[Value]:
# specialized implementation is used if:
# - only one or two arguments given (if not, sum() has been given invalid arguments)
# - first argument is a Generator (there is no benefit to optimizing the performance of eg.
# sum([1, 2, 3]), so non-Generator Iterables are not handled)
if not (len(expr.args) in (1, 2) and expr.arg_kinds[0] == ARG_POS
and isinstance(expr.args[0], GeneratorExpr)):
return None
# handle 'start' argument, if given
if len(expr.args) == 2:
# ensure call to sum() was properly constructed
if not expr.arg_kinds[1] in (ARG_POS, ARG_NAMED):
return None
start_expr = expr.args[1]
else:
start_expr = IntExpr(0)
gen_expr = expr.args[0]
target_type = builder.node_type(expr)
retval = Register(target_type)
builder.assign(retval,
builder.coerce(builder.accept(start_expr), target_type, -1),
-1)
def gen_inner_stmts() -> None:
call_expr = builder.accept(gen_expr.left_expr)
builder.assign(retval, builder.binary_op(retval, call_expr, '+', -1),
-1)
loop_params = list(
zip(gen_expr.indices, gen_expr.sequences, gen_expr.condlists))
comprehension_helper(builder, loop_params, gen_inner_stmts, gen_expr.line)
return retval
