def transform_Mul(self, node):
if node.is_int:
return ir.IntConst(node.evaluate_int(self.prog))
# We are guaranteed that node.a will be an integer, so we don't need to worry about transforming it
c = node.a.evaluate_int(prog) # copy of a
negative = False
if c == 0:
return ir.IntConst(0)
if c < 0:
negative = True
c = -c
self.expr_depth += 1
power = self.transform(node.b)
self.expr_depth -= 1
s = ir.IntConst(0)
while True:
if c & 1 == 1:
s = ir.Add(power, s)
c = c // 2
if c <= 0:
break
power = ir.Add(power, power)
if negative:
return ir.Sub(ir.IntConst(0), s)
else:
return s
def transform_Div(self, node):
if node.is_int:
return ir.IntConst(node.evaluate_int(self.prog))
new_var = VarRef(ir.IRNode.fresh_name())
return self.transform(
PredicateExpr(
new_var.var_name,
TypeHint(new_var, node.a, Equals(node.a, Mul(node.b,
new_var)))))
def transform_Mul(self, node):
# If they are both ints, translate to an IR node that will multiply
# This will fail at runtime if one/both of the variables doesn't get substituted before this runs
if not node.a.is_int and not node.b.is_int:
return ir.Mul(self.transform(node.a), self.transform(node.b))
# We assumed above that a was the int, but it might not be; if it wasn't, just swap the two
if not node.a.is_int:
node.a, node.b = node.b, node.a
if node.is_int:
return ir.IntConst(node.evaluate_int(self.prog))
# We are guaranteed that node.a will be an integer, so we don't need to worry about transforming it
c = node.a.evaluate_int(prog) # copy of a
negative = False
if c == 0:
return ir.IntConst(0)
if c < 0:
negative = True
c = -c
self.expr_depth += 1
power = self.transform(node.b)
self.expr_depth -= 1
s = ir.IntConst(0)
while True:
if c & 1 == 1:
s = ir.Add(power, s)
c = c // 2
if c <= 0:
break
power = ir.Add(power, power)
if negative:
return ir.Sub(ir.IntConst(0), s)
else:
return s
def transform_IntConst(self, node):
return ir.IntConst(node.val)