factor function in llvm assembler

factor

@str = internal constant [4 x i8] c"%d\0a\00"

declare i32 @printf(i8*, ...)

define i32 @factor(i32 %n) {
head:
  %cast_message = getelementptr [4 x i8]* @str, i32 0, i32 0
  %i = alloca i32
  store i32 2, i32* %i
  br label %loop

loop:
  %val = load i32* %i
  %rem = urem i32 %n, %val
  %isdivider = icmp eq i32 %rem, 0
  br i1 %isdivider, label %print, label %next

print:
  call i32 (i8*, ...)* @printf(i8* %cast_message, i32 %val)
  br label %next

next:
  %ival = add i32 %val, 1
  store i32 %ival, i32* %i
  %b = icmp sle i32 %ival, %n
  br i1 %b, label %loop, label %tail

tail:
  ret i32 0
}

define i32 @main() {
  call i32(i32)* @factor(i32 40)
  ret i32 0
}