import unittest
from copy import copy

from src.optimize.advanced import eliminate_common_subexpressions, \
        fold_constants, copy_propagation, algebraic_transformations
from src.statement import Statement as S, Block as B
import src.liveness as liveness


class TestOptimizeAdvanced(unittest.TestCase):

    def setUp(self):
        self.foo = S('command', 'foo')
        self.bar = S('command', 'bar')

    def tearDown(self):
        del self.foo
        del self.bar

    def test_eliminate_common_subexpressions_simple(self):
        b = B([S('command', 'addu', '$regC', '$regA', '$regB'),
               S('command', 'addu', '$regD', '$regA', '$regB')])
        e = [S('command', 'addu', '$8', '$regA', '$regB'), \
             S('command', 'move', '$regC', '$8'), \
             S('command', 'move', '$regD', '$8')]
        liveness.create_in_out([b])
        eliminate_common_subexpressions(b)
        self.assertEqual(b.statements, e)

    def test_eliminate_common_subexpressions_assigned(self):
        b = B([S('command', 'addu', '$regC', '$regA', '$regB'),
               S('command', 'li', '$regA', '0x00000001'),
               S('command', 'addu', '$regD', '$regA', '$regB')])
        e = copy(b.statements)
        liveness.create_in_out([b])
        eliminate_common_subexpressions(b)
        self.assertEqual(b.statements, e)

    def test_fold_constants(self):
        pass

    def test_copy_propagation_true(self):
        block = B([self.foo,
                   S('command', 'move', '$1', '$2'),
                   self.foo,
                   S('command', 'addu', '$3', '$1', '$4'),
                   self.bar])

        self.assertTrue(copy_propagation(block))
        self.assertEqual(block.statements, [self.foo,
                   S('command', 'move', '$1', '$2'),
                   self.foo,
                   S('command', 'addu', '$3', '$2', '$4'),
                   self.bar])

    def test_copy_propagation_other_arg(self):
        block = B([self.foo,
                   S('command', 'move', '$1', '$2'),
                   self.foo,
                   S('command', 'addu', '$3', '$4', '$1'),
                   self.bar])

        self.assertTrue(copy_propagation(block))
        self.assertEqual(block.statements, [self.foo,
                   S('command', 'move', '$1', '$2'),
                   self.foo,
                   S('command', 'addu', '$3', '$4', '$2'),
                   self.bar])

    def test_copy_propagation_overwrite(self):
        block = B([self.foo, \
                    S('command', 'move', '$1', '$2'),
                    S('command', 'move', '$1', '$5'),
                    S('command', 'addu', '$3', '$1', '$4'),
                    self.bar])

        self.assertTrue(copy_propagation(block))
        self.assertEqual(block.statements, [self.foo,
                   S('command', 'move', '$1', '$2'),
                   S('command', 'move', '$1', '$5'),
                   S('command', 'addu', '$3', '$5', '$4'),
                   self.bar])

    def test_copy_propagation_false(self):
        arguments = [self.foo,
                   S('command', 'move', '$1', '$2'),
                   S('command', 'move', '$10', '$20'),
                   S('command', 'addu', '$1', '$5', 1),
                   S('command', 'addu', '$3', '$1', '$4'),
                   self.bar]
        block = B(arguments)
        self.assertFalse(copy_propagation(block))
        self.assertEqual(block.statements, arguments)

    def test_copy_propagation_false_severalmoves(self):
        arguments = [self.foo,
                   S('command', 'move', '$1', '$2'),
                   self.foo,
                   S('command', 'addu', '$1', '$5', 1),
                   S('command', 'addu', '$3', '$1', '$4'),
                   self.bar]
        block = B(arguments)
        self.assertFalse(copy_propagation(block))
        self.assertEqual(block.statements, arguments)

    def test_algebraic_transforms_add0(self):
        block = B([self.foo,
                   S('command', 'addu', '$1', '$2', 0),
                   self.bar])
        self.assertTrue(algebraic_transformations(block))
        self.assertEqual(block.statements, [self.foo,
                         S('command', 'move', '$1', '$2'),
                         self.bar])

    def test_algebraic_transforms_add1(self):
        arguments = [self.foo,
                   S('command', 'addu', '$1', '$2', 1),
                   self.bar]
        block = B(arguments)

        self.assertFalse(algebraic_transformations(block))
        self.assertEqual(block.statements, arguments)

    def test_algebraic_transforms_sub0(self):
        block = B([self.foo,
                   S('command', 'subu', '$1', '$2', 0),
                   self.bar])

        self.assertTrue(algebraic_transformations(block))
        self.assertEqual(block.statements, [self.foo,
                         S('command', 'move', '$1', '$2'),
                         self.bar])

    def test_algebraic_transforms_sub1(self):
        arguments = [self.foo,
                   S('command', 'subu', '$1', '$2', 1),
                   self.bar]
        block = B(arguments)

        self.assertFalse(algebraic_transformations(block))
        self.assertEqual(block.statements, arguments)

    def test_algebraic_transforms_mult0(self):
        block = B([self.foo,
                   S('command', 'mult', '$2', 0),
                   S('command', 'mflo', '$1'),
                   self.bar])

        self.assertTrue(algebraic_transformations(block))
        self.assertEqual(block.statements, [self.foo,
                         S('command', 'li', '$1', '0x00000000'),
                         self.bar])

    def test_algebraic_transforms_mult1(self):
        block = B([self.foo,
                   S('command', 'mult', '$2', 1),
                   S('command', 'mflo', '$1'),
                   self.bar])

        self.assertTrue(algebraic_transformations(block))
        self.assertEqual(block.statements, [self.foo,
                         S('command', 'move', '$1', '$2'),
                         self.bar])

    def test_algebraic_transforms_mult2(self):
        block = B([self.foo,
                   S('command', 'mult', '$2', 2),
                   S('command', 'mflo', '$1'),
                   self.bar])

        self.assertTrue(algebraic_transformations(block))
        self.assertEqual(block.statements, [self.foo,
                         S('command', 'sll', '$1', '$2', 1),
                         self.bar])

    def test_algebraic_transforms_mult16(self):
        block = B([self.foo,
                   S('command', 'mult', '$2', 16),
                   S('command', 'mflo', '$1'),
                   self.bar])

        self.assertTrue(algebraic_transformations(block))
        self.assertEqual(block.statements, [self.foo,
                         S('command', 'sll', '$1', '$2', 4),
                         self.bar])

    def test_algebraic_transforms_mult3(self):
        arguments = [self.foo,
                     S('command', 'mult', '$2', 3),
                     S('command', 'mflo', '$1'),
                     self.bar]
        block = B(arguments)

        self.assertFalse(algebraic_transformations(block))
        self.assertEqual(block.statements, arguments)