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 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 if not isinstance(node.func, ast.Attribute): raise BaseException("Wrong type of function") 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_get_rep_works_and_doesnt(): g = generated_code() s1 = statement.iftest("true") g.set_rep("dude", 5) assert 5 is g.get_rep("dude") g.pop_scope() assert None is g.get_rep("dude")
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 test_nothing_else_starts_with_top_level_scope(): top = gc_scope_top_level() g = generated_code() s1 = statement.iftest("true") g.add_statement(s1) scope_1 = g.current_scope() assert not top.starts_with(scope_1)
def test_everything_starts_with_top_level_scope(): top = gc_scope_top_level() g = generated_code() s1 = statement.iftest("true") g.add_statement(s1) scope_1 = g.current_scope() assert scope_1.starts_with(top)
def test_get_rep_hidden(): g = generated_code() g.set_rep("dude", 5) s1 = statement.iftest("true") g.add_statement(s1) g.set_rep("dude", 10) assert 10 is g.get_rep("dude") g.pop_scope() assert 5 is g.get_rep("dude")
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', top_level_scope(), 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. # Protect against sequence of sequences (LOVE type checkers, which caught this as a possibility) w_val = seq.sequence_value() if isinstance(w_val, crep.cpp_sequence): raise BaseException( "Internal error: don't know how to look at a sequence") new_sequence_var = w_val.copy_with_new_scope(self._gc.current_scope()) node.rep = crep.cpp_sequence(new_sequence_var, seq.iterator_value()) self._result = node.rep
def test_get_rep_when_set_level_up(): g = generated_code() g.set_rep("dude", 5) s1 = statement.iftest("true") g.add_statement(s1) assert 5 is g.get_rep("dude")