def cgen_for(node):
emit_comment('cgen_for')
expr1 = node.ref_child[0]
expr2 = node.ref_child[1]
expr3 = node.ref_child[2]
stmt = node.ref_child[3]
top = ut.disFp
l1 = create_label()
l2 = create_label()
node.attribute[AttName.exit_label] = l2
if expr1.data != "nothing":
cgen_expr(expr1)
align_stack(top)
emit_label(l1)
t = cgen_expr(expr2)
if t.attribute[AttName.type] != Type.bool:
raise TypeError("error in node " + str(node) +
"\n type of the decision statement must be bool!")
t.attribute[AttName.address].load_address()
emit_load("$t0", "$s0")
align_stack(top)
emit("beqz $t0, " + l2)
cgen_stmt(stmt)
align_stack(top)
if expr3.data != "nothing":
cgen_expr(expr3)
align_stack(top)
emit_jump(l1)
emit_label(l2)
emit_li("$t6", top)
ut.emit_add("$t6", "$t6", "$fp")
emit_move("$sp", "$t6")
return
def print_double():
l1 = create_label()
l2 = create_label()
emit('la $s0, __epsilon')
emit('l.s $f1, 0($s0)')
emit('abs.s $f7, $f0')
emit('c.eq.s $f7, $f0')
emit('bc1t ' + l1)
emit('sub.s $f0, $f0, $f1')
emit_jump(l2)
emit_label(l1)
emit('add.s $f0, $f0, $f1')
emit_label(l2)
emit('cvt.w.s $f1, $f0')
emit('mfc1 $a0, $f1')
emit_li('$v0', 1)
emit_syscall()
emit('la $a0, __dot')
emit_li('$v0', 4)
emit_syscall()
emit('abs.s $f0, $f0')
emit('cvt.w.s $f1, $f0')
emit('cvt.s.w $f1, $f1')
emit('sub.s $f0, $f0, $f1')
emit('la $s0, __ten')
emit('l.s $f3, 0($s0)')
for i in range(4):
emit('mul.s $f0, $f0, $f3')
emit('cvt.w.s $f1, $f0')
emit('mfc1 $a0, $f1')
emit('cvt.s.w $f1, $f1')
emit('sub.s $f0, $f0, $f1')
emit_li('$v0', 1)
emit_syscall()
def cgen_if1(expr, stmt1, stmt2):
emit_comment('cgen_if1')
l1 = create_label()
l2 = create_label()
top = ut.disFp
t1 = cgen_expr(expr)
if t1.attribute[AttName.type] != Type.bool:
raise TypeError("error in node " + str(expr) +
"\n type of the decision statement must be bool!")
t1.attribute[AttName.address].load_address()
emit_load("$t0", "$s0")
align_stack(top)
emit("beqz $t0, " + l1)
st1 = cgen_stmt(stmt1)
ret = 0
if st1.attribute[AttName.has_return]:
ret += 1
align_stack(top)
emit_jump(l2)
emit_label(l1)
st2 = cgen_stmt(stmt2)
if st2.attribute[AttName.has_return]:
ret += 1
align_stack(top)
emit_label(l2)
return ret
def cgen_expr_equal(node):
emit_comment('cgen_expr_equal')
stack_handler.add_checkpoint()
left_child = cgen_expr(node.ref_child[0])
right_child = cgen_expr(node.ref_child[2])
left_child_address = left_child.get_address()
right_child_address = right_child.get_address()
if not expr_convertable(left_child.get_type(),
right_child.get_type()) and not expr_convertable(
right_child.get_type(), left_child.get_type()):
emit_li("$s0", 0)
elif left_child.get_type() == Type.double:
expr_float_cmp(left_child_address, right_child_address, 'eq')
elif left_child.get_type() == Type.string:
left_child_address.load()
emit_move('$s1', '$s0')
right_child_address.load()
emit_move('$s2', '$s0')
emit_li('$s0', 1)
first_label = create_label()
second_label = create_label()
out_label = create_label()
emit_label(first_label)
emit_load_byte('$t0', '$s1')
emit_load_byte('$t1', '$s2')
emit_addi('$s1', '$s1', '1')
emit_addi('$s2', '$s2', '1')
emit('beq $t0, $t1, ' + second_label)
emit_li('$s0', 0)
emit_label(second_label)
emit('beqz $t0, ' + out_label)
emit('beqz $t1, ' + out_label)
emit_jump(first_label)
emit_label(out_label)
else:
left_child_address.load()
emit_move('$s1', '$s0')
right_child_address.load()
emit("xor $t0, $s0, $s1")
emit("slt $t1, $t0, $zero")
emit("slt $t0, $zero, $t0")
emit("or $t0, $t0, $t1")
emit("li $t1, 1")
emit("sub $s0, $t1, $t0")
emit("")
stack_handler.back_to_last_checkpoint()
expr_set_node_attributes(node, Type.bool)
node.get_address().store()
return node
def cgen_readline(
node): # after calling this function address of the string is in $S0
emit_comment('cgen_readline()')
l1 = create_label()
l2 = create_label()
l3 = create_label()
l4 = create_label()
ut.disFp -= 4
node.set_address(Address(ut.disFp, 0, False))
node.set_type(Type.string)
emit_addi("$sp", "$sp", "-4")
emit('''li $v0, 8
li $a1, 400
la $a0, __read
syscall
li $a1, 1
li $a2, 0''')
emit_label(l1)
emit('''lbu $a2, 0($a0)
li $a3, 10''')
emit("beq $a2, $a3, " + l2)
emit_li('$a3', 13)
emit("beq $a2, $a3, " + l2)
emit_li('$a3', 0)
emit("beq $a2, $a3, " + l2)
emit_addi('$a1', '$a1', '1')
emit_addi('$a0', '$a0', '1')
emit_jump(l1)
emit_label(l2)
emit('''li $v0, 9
move $a0, $a1
syscall
move $v1, $v0
la $a0, __read''')
emit_label(l3)
emit('''lbu $a2, 0($a0)
sb $zero, 0($a0)
li $a3, 10''')
emit("beq $a2, $a3, " + l4)
emit_li('$a3', 13)
emit("beq $a2, $a3, " + l4)
emit_li('$a3', 0)
emit("beq $a2, $a3, " + l4)
emit('''sb $a2, 0($v0)
addi $v0, $v0, 1
addi $a0, $a0, 1''')
emit_jump(l3)
emit_label(l4)
emit("sw $v1, 0($sp)")
return node
def cgen_break(node):
emit_comment('cgen_break')
parent = node.ref_parent
while parent is not None:
data = parent.data
if data == "whilestmt" or data == "forstmt":
break
parent = parent.ref_parent
if parent is None:
error("Error in break statement, break isn't in a loop!")
emit_jump(parent.attribute[AttName.exit_label])
return
def cgen_print_stmt(node):
emit_comment('cgen_print_stmt')
top = ut.disFp
for child in node.ref_child:
expr = cgen_expr(child)
address = expr.attribute[AttName.address]
type = expr.attribute[AttName.type]
address.load_address()
if type == Type.double:
emit_load_double("$f12", "$s0")
emit_li("$v0", 2)
emit_syscall()
#print_double()
elif type == "string":
emit_load("$a0", "$s0")
emit_li("$v0", 4)
emit_syscall()
elif type == Type.bool:
l1 = create_label()
l2 = create_label()
emit_load('$s0', '$s0')
emit('beqz $s0, ' + l1)
emit('la $a0, __true')
emit_jump(l2)
emit_label(l1)
emit('la $a0, __false')
emit_label(l2)
emit_li("$v0", 4)
emit_syscall()
else:
emit_load("$a0", "$s0")
emit_li("$v0", 1)
emit_syscall()
align_stack(top)
emit('la $a0, __newLine')
emit_li("$v0", 4)
emit_syscall()
def cgen_readint(node):
L1 = create_label()
L2 = create_label()
L3 = create_label()
L4 = create_label()
L5 = create_label()
L6 = create_label()
L7 = create_label()
L8 = create_label()
L9 = create_label()
L10 = create_label()
L7_ = create_label()
L_1 = create_label()
L_2 = create_label()
L_3 = create_label()
L_4 = create_label()
L_5 = create_label()
L_6 = create_label()
L_7 = create_label()
exitt = create_label()
exit = create_label()
LL1 = create_label()
LL2 = create_label()
LL3 = create_label()
LL4 = create_label()
LL5 = create_label()
LL6 = create_label()
LL7 = create_label()
LL8 = create_label()
expr_set_node_attributes(node, Type.int)
emit_li('$v0', 8)
emit_li('$a1', 400)
emit('la $a0, __read')
emit_li('$t0', 0)
emit_li('$t1', 0)
emit_li('$t4', 10)
emit_syscall()
emit_load_byte('$t2', '$a0')
emit_addi('$a0', '$a0', '1')
emit_li('$t3', 13)
emit('bne $t3, $t2, ' + LL1)
emit_jump(exit)
emit_label(LL1)
emit_li('$t3', 0)
emit('bne $t3, $t2, ' + LL2)
emit_jump(exit)
emit_label(LL2)
emit_li('$t3', 10)
emit('bne $t3, $t2, ' + L1)
emit_jump(exit)
emit_label(L1)
emit_li('$t3', 45)
emit('bne $t3, $t2, ' + L2)
emit_li('$t1', 1)
emit_jump(L3)
emit_label(L2)
emit_li('$t3', 43)
emit('bne $t3, $t2, ' + L4)
emit_label(L3)
emit_load_byte('$t2', '$a0')
emit_addi('$a0', '$a0', '1')
emit_label(L4)
emit_li('$t3', 13)
emit('bne $t2, $t3, ' + LL3)
emit_jump(exit)
emit_label(LL3)
emit_li('$t3', 0)
emit('bne $t2, $t3, ' + LL4)
emit_jump(exit)
emit_label(LL4)
emit_li('$t3', 10)
emit('bne $t2, $t3, ' + L_7)
emit_jump(exit)
emit_label(L_7)
emit_addi('$t2', '$t2', '-48')
emit_li('$t3', 0)
emit('bge $t2, $t3, ' + L5)
emit_li('$t1', -1)
emit_jump(L_1)
emit_label(L5)
emit_li('$t3', 10)
emit('bgt $t3, $t2, ' + L6)
emit_li('$t1', -1)
emit_jump(L_1)
emit_label(L6)
emit_li('$t3', 0)
emit_move('$t0', '$t2')
emit('bne $t2, $t3, ' + L_1)
emit_load_byte('$t2', '$a0')
emit_addi('$a0', '$a0', '1')
emit_li('$t3', 13)
emit('bne $t2, $t3, ' + LL5)
emit_jump(exit)
emit_label(LL5)
emit_li('$t3', 0)
emit('bne $t2, $t3, ' + LL6)
emit_jump(exit)
emit_label(LL6)
emit_li('$t3', 10)
emit('bne $t2, $t3, ' + L7)
emit_jump(exit)
emit_label(L7)
emit_li('$t3', 88)
emit('beq $t2, $t3, ' + L7_)
emit_li('$t3', 120)
emit('beq $t2, $t3, ' + L7_)
emit_jump(L8)
emit_label(L7_)
emit_li('$t4', 16)
emit_jump(L_1)
emit_label(L8)
emit_li('$t3', 48)
emit('bge $t2, $t3, ' + L9)
emit_li('$t1', -1)
emit_jump(L_1)
emit_label(L9)
emit_li('$t3', 57)
emit('ble $t2, $t3, ' + L10)
emit_li('$t1', -1)
emit_jump(L_1)
emit_label(L10)
emit_addi('$t2', '$t2', '-48')
emit_move('$t0', '$t2')
emit_label(L_1)
emit_load_byte('$t2', '$a0')
emit_addi('$a0', '$a0', '1')
emit_li('$t3', 13)
emit('bne $t2, $t3, ' + LL7)
emit_jump(exitt)
emit_label(LL7)
emit_li('$t3', 0)
emit('bne $t2, $t3, ' + LL8)
emit_jump(exitt)
emit_label(LL8)
emit_li('$t3', 10)
emit('bne $t2, $t3, ' + L_2)
emit_jump(exitt)
emit_label(L_2)
emit_li('$t3', 48)
emit('blt $t2, $t3, ' + L_5)
emit_li('$t3', 57)
emit('bgt $t2, $t3, ' + L_3)
emit_addi('$t2', '$t2', '-48')
emit('mul $t0, $t0, $t4')
emit('add $t0, $t0, $t2')
emit_jump(L_1)
emit_label(L_3)
emit_li('$t3', 65)
emit('blt $t2, $t3, ' + L_5)
emit_li('$t3', 70)
emit('bgt $t2, $t3, ' + L_4)
emit_addi('$t2', '$t2', '-55')
emit('bge $t2, $t4, ' + L_5)
emit('mul $t0, $t0, $t4')
emit('add $t0, $t0, $t2')
emit_jump(L_1)
emit_label(L_4)
emit_li('$t3', 97)
emit('blt $t2, $t3, ' + L_5)
emit_li('$t3', 102)
emit('bgt $t2, $t3, ' + L_5)
emit_addi('$t2', '$t2', '-87')
emit('bge $t2, $t4, ' + L_5)
emit('mul $t0, $t0, $t4')
emit('add $t0, $t0, $t2')
emit_jump(L_1)
emit_label(L_5)
emit_li('$t1', -1)
emit_jump(L_1)
emit_label(exitt)
emit_li('$t4', -1)
emit('bne $t4, $t1, ' + L_6)
emit_li('$t0', 0)
emit_jump(exit)
emit_label(L_6)
emit_li('$t4', 1)
emit('bne $t4, $t1, ' + exit)
emit('sub $t0, $zero, $t0')
emit_label(exit)
emit_move('$s0', '$t0')
node.get_address().store()
return node