def test_get(self):
self.assertEqual("00000", UUID_TICKETS.get())
self.assertEqual("label_00000", LABEL_TICKETS.get())
self.assertEqual("ireg_00000", INT_REGISTER_TICKETS.get())
self.assertEqual("freg_00000", FLOAT_REGISTER_TICKETS.get())
self.assertEqual("00001", UUID_TICKETS.get())
self.assertEqual("label_00001", LABEL_TICKETS.get())
self.assertEqual("ireg_00001", INT_REGISTER_TICKETS.get())
self.assertEqual("freg_00001", FLOAT_REGISTER_TICKETS.get())
def test_overrun_of_spill_memory_fails(self):
with self.assertRaises(OutOfSpillMemoryException):
# 6 is precisely enough to run out of spill memory
pseudo_registers = [
INT_REGISTER_TICKETS.get() for _ in range(0, 6)
]
for pseudo_register in pseudo_registers:
self.register_use_table.acquire(pseudo_register)
def test_register_spill(self):
pseudo_registers = [INT_REGISTER_TICKETS.get() for _ in range(0, 3)]
self.register_use_table.acquire(pseudo_registers[0])
self.register_use_table.acquire(pseudo_registers[1])
self.assertSequenceEqual([], self.register_use_table.available_registers, 'the registers should be used up')
expected_result = {'register': mips.T0, 'code': [assembler.SW(mips.T0, assembler.offset_label_immediate(SPILL_MEM_LABEL, 0))]}
result = self.register_use_table.acquire(pseudo_registers[2])
self.assertEqual(expected_result, result)
def test_spill_recovery(self):
pseudo_registers = [INT_REGISTER_TICKETS.get() for _ in range(0, 3)]
self.register_use_table.acquire(pseudo_registers[0])
self.register_use_table.acquire(pseudo_registers[1])
self.assertSequenceEqual([], self.register_use_table.available_registers, 'the registers should be used up')
expected_result = {'register': mips.T0, 'code': [assembler.SW(mips.T0, assembler.offset_label_immediate(SPILL_MEM_LABEL, 0))]}
result = self.register_use_table.acquire(pseudo_registers[2])
self.assertEqual(expected_result, result)
# recovering a spilled register's value from memory should not only get the register, but also provide the
# mips code that swaps the values for the temporaries using the spill memory
expected_result = {'register': mips.T1, 'code': [assembler.SW(mips.T1, assembler.offset_label_immediate(SPILL_MEM_LABEL, 4)),
assembler.LW(mips.T1, assembler.offset_label_immediate(SPILL_MEM_LABEL, 0))]}
result = self.register_use_table.acquire(pseudo_registers[0])
self.assertEqual(expected_result, result)
def test_single_register_use(self):
pseudo_register = INT_REGISTER_TICKETS.get()
self.assertFalse(pseudo_register in self.register_use_table.lru_cache)
result = self.register_use_table.acquire(pseudo_register)
expected_result = {'register': mips.T0, 'code': []}
self.assertEqual(expected_result, result, 'register $t0 should have been returned and no code required')
# since no spilling occurred, we should get the same register back with no code needed
result = self.register_use_table.acquire(pseudo_register)
self.assertEqual(expected_result, result, 'register $t0 should have been returned and no code required')
self.register_use_table.release(pseudo_register)
self.assertFalse(pseudo_register in self.register_use_table.lru_cache)
self.assertSequenceEqual([mips.T1, mips.T0], self.register_use_table.available_registers)
def test_register_spill(self):
pseudo_registers = [INT_REGISTER_TICKETS.get() for _ in range(0, 3)]
self.register_use_table.acquire(pseudo_registers[0])
self.register_use_table.acquire(pseudo_registers[1])
self.assertSequenceEqual([],
self.register_use_table.available_registers,
'the registers should be used up')
expected_result = {
'register':
mips.T0,
'code': [
assembler.SW(
mips.T0,
assembler.offset_label_immediate(SPILL_MEM_LABEL, 0))
]
}
result = self.register_use_table.acquire(pseudo_registers[2])
self.assertEqual(expected_result, result)
def test_spill_recovery(self):
pseudo_registers = [INT_REGISTER_TICKETS.get() for _ in range(0, 3)]
self.register_use_table.acquire(pseudo_registers[0])
self.register_use_table.acquire(pseudo_registers[1])
self.assertSequenceEqual([],
self.register_use_table.available_registers,
'the registers should be used up')
expected_result = {
'register':
mips.T0,
'code': [
assembler.SW(
mips.T0,
assembler.offset_label_immediate(SPILL_MEM_LABEL, 0))
]
}
result = self.register_use_table.acquire(pseudo_registers[2])
self.assertEqual(expected_result, result)
# recovering a spilled register's value from memory should not only get the register, but also provide the
# mips code that swaps the values for the temporaries using the spill memory
expected_result = {
'register':
mips.T1,
'code': [
assembler.SW(
mips.T1,
assembler.offset_label_immediate(SPILL_MEM_LABEL, 4)),
assembler.LW(
mips.T1,
assembler.offset_label_immediate(SPILL_MEM_LABEL, 0))
]
}
result = self.register_use_table.acquire(pseudo_registers[0])
self.assertEqual(expected_result, result)
def test_single_register_use(self):
pseudo_register = INT_REGISTER_TICKETS.get()
self.assertFalse(pseudo_register in self.register_use_table.lru_cache)
result = self.register_use_table.acquire(pseudo_register)
expected_result = {'register': mips.T0, 'code': []}
self.assertEqual(
expected_result, result,
'register $t0 should have been returned and no code required')
# since no spilling occurred, we should get the same register back with no code needed
result = self.register_use_table.acquire(pseudo_register)
self.assertEqual(
expected_result, result,
'register $t0 should have been returned and no code required')
self.register_use_table.release(pseudo_register)
self.assertFalse(pseudo_register in self.register_use_table.lru_cache)
self.assertSequenceEqual([mips.T1, mips.T0],
self.register_use_table.available_registers)
def test_overrun_of_spill_memory_fails(self):
with self.assertRaises(OutOfSpillMemoryException):
# 6 is precisely enough to run out of spill memory
pseudo_registers = [INT_REGISTER_TICKETS.get() for _ in range(0, 6)]
for pseudo_register in pseudo_registers:
self.register_use_table.acquire(pseudo_register)
