def test_deepest_scope_one_greater():
g = generated_code()
s1 = statement.iftest("true")
s2 = statement.iftest("true")
g.add_statement(s1)
scope_1 = g.current_scope()
g.add_statement(s2)
scope_2 = g.current_scope()
v1 = crep.cpp_value("v1", scope_1, ctyp.terminal('int'))
v2 = crep.cpp_value("v2", scope_2, ctyp.terminal('int'))
assert v2 == deepest_scope(v1, v2)
assert v2 == deepest_scope(v2, v1)
def visit_BoolOp(self, node):
'''A bool op like And or Or on a set of values
This is a bit more complex than just "anding" things as we want to make sure to short-circuit the
evaluation if we need to.
'''
# The result of this test
result = crep.cpp_variable(unique_name('bool_op'),
self._gc.current_scope(),
cpp_type='bool')
self._gc.declare_variable(result)
# How we check and short-circuit depends on if we are doing and or or.
check_expr = result.as_cpp() if type(
node.op) == ast.And else '!{0}'.format(result.as_cpp())
check = crep.cpp_value(check_expr,
self._gc.current_scope(),
cpp_type='bool')
first = True
scope = self._gc.current_scope()
for v in node.values:
if not first:
self._gc.add_statement(statement.iftest(check))
rep_v = self.get_rep(v)
self._gc.add_statement(statement.set_var(result, rep_v))
if not first:
self._gc.set_scope(scope)
first = False
# Cache result variable so those above us have something to use.
self._result = result
node.rep = result
def visit_IfExp(self, node):
r'''
We'd like to be able to use the "?" operator in C++, but the
problem is lazy evaluation. It could be when we look at one or the
other item, a bunch of prep work has to be done - and that will
show up in separate statements. So we have to use if/then/else with
a result value.
'''
# The result we'll store everything in.
result = crep.cpp_variable(unique_name("if_else_result"),
self._gc.current_scope(),
cpp_type=ctyp.terminal("double"))
self._gc.declare_variable(result)
# We always have to evaluate the test.
current_scope = self._gc.current_scope()
test_expr = self.get_rep(node.test)
self._gc.add_statement(statement.iftest(test_expr))
if_scope = self._gc.current_scope()
# Next, we do the true and false if statement.
self._gc.add_statement(
statement.set_var(result, self.get_rep(node.body)))
self._gc.set_scope(if_scope)
self._gc.pop_scope()
self._gc.add_statement(statement.elsephrase())
self._gc.add_statement(
statement.set_var(result, self.get_rep(node.orelse)))
self._gc.set_scope(current_scope)
# Done, the result is the rep of this node!
node.rep = result
self._result = result
def test_insert_in_middle():
s1 = statement.iftest("true")
s2 = statement.set_var("v1", "true")
g = generated_code()
g.add_statement(s1)
g.add_statement(s2)
s3 = statement.iftest("fork")
g.add_statement(s3, below=s1)
assert 1 == len(s1._statements)
assert 1 == len(s3._statements)
assert s1._statements[0] is s3
assert s3._statements[0] is s2
def visit_Call_Aggregate_only(self, node: ast.Call):
'''
- (acc lambda): the accumulator is set to the first element, and the lambda is called to
update it after that. This is called `agg_only`.
'''
agg_lambda = node.args[0]
# Get the sequence we are calling against and the accumulator
seq = self.as_sequence(node.func.value)
accumulator, accumulator_scope = self.create_accumulator(seq)
# We have to do a simple if statement here so that the first time through we can set the
# accumulator, and the second time we can add to it.
is_first_iter = crep.cpp_variable(unique_name("is_first"),
self._gc.current_scope(),
cpp_type=ctyp.terminal('bool'),
initial_value=crep.cpp_value(
'true', self._gc.current_scope(),
ctyp.terminal('bool')))
accumulator_scope.declare_variable(is_first_iter)
# Set the scope where we will be doing the accumulation
sv = seq.sequence_value()
if isinstance(sv, crep.cpp_sequence):
self._gc.set_scope(sv.iterator_value().scope()[-1])
else:
self._gc.set_scope(sv.scope())
# Code up if statement to select out the first element.
if_first = statement.iftest(is_first_iter)
self._gc.add_statement(if_first)
self._gc.add_statement(
statement.set_var(
is_first_iter,
crep.cpp_value("false", self._gc.current_scope(),
ctyp.terminal('bool'))))
# Set the accumulator
self._gc.add_statement(
statement.set_var(accumulator, seq.sequence_value()))
self._gc.pop_scope()
# Now do the if statement and make the call to calculate the accumulation.
self._gc.add_statement(statement.elsephrase())
call = ast.Call(
func=agg_lambda,
args=[accumulator.as_ast(),
seq.sequence_value().as_ast()])
self._gc.add_statement(
statement.set_var(accumulator, self.get_rep(call)))
# Finally, since this is a terminal, we need to pop off the top.
self._gc.set_scope(accumulator_scope)
# Cache the results in our result in case we are skipping nodes in the AST.
node.rep = accumulator
self._result = accumulator
def test_insert_two_levels():
s1 = statement.iftest("true")
s2 = statement.set_var("v1", "true")
g = generated_code()
g.add_statement(s1)
g.add_statement(s2)
assert 1 == len(s1._statements)
def visit_First(self, node):
'We are in a sequence. Take the first element of the sequence and use that for future things.'
# Make sure we are in a loop.
seq = self.as_sequence(node.source)
# The First terminal works by protecting the code with a if (first_time) {} block.
# We need to declare the first_time variable outside the block where the thing we are
# looping over here is defined. This is a little tricky, so we delegate to another method.
loop_scope = seq.iterator_value().scope()
outside_block_scope = loop_scope[-1]
# Define the variable to track this outside that block.
is_first = crep.cpp_variable(unique_name('is_first'),
outside_block_scope,
cpp_type=ctyp.terminal('bool'),
initial_value=crep.cpp_value(
'true', self._gc.current_scope(),
ctyp.terminal('bool')))
outside_block_scope.declare_variable(is_first)
# Now, as long as is_first is true, we can execute things inside this statement.
# The trick is putting the if statement in the right place. We need to locate it just one level
# below where we defined the scope above.
s = statement.iftest(is_first)
s.add_statement(
statement.set_var(
is_first,
crep.cpp_value('false', None, cpp_type=ctyp.terminal('bool'))))
sv = seq.sequence_value()
if isinstance(sv, crep.cpp_sequence):
self._gc.set_scope(sv.iterator_value().scope()[-1])
else:
self._gc.set_scope(sv.scope())
self._gc.add_statement(s)
# If we just found the first sequence in a sequence, return that.
# Otherwise return a new version of the value.
first_value = sv if isinstance(
sv, crep.cpp_sequence) else sv.copy_with_new_scope(
self._gc.current_scope())
node.rep = first_value
self._result = first_value
def visit_Where(self, node):
'Apply a filtering to the current loop.'
# Make sure we are in a loop
seq = self.as_sequence(node.source)
# Simulate the filtering call - we want the resulting value to test.
filter = lambda_unwrap(node.filter)
c = ast.Call(func=filter, args=[seq.sequence_value().as_ast()])
rep = self.get_rep(c)
# Create an if statement
self._gc.add_statement(statement.iftest(rep))
# Ok - new sequence. This the same as the old sequence, only the sequence value is updated.
new_sequence_var = seq.sequence_value().copy_with_new_scope(
self._gc.current_scope())
node.rep = crep.cpp_sequence(new_sequence_var, seq.iterator_value())
self._result = node.rep