extern crate llvm;
use llvm::*;
use llvm::Attribute::*;
fn main() {
let ctx = Context::new();
let module = Module::new("simple", &ctx);
let func = module.add_function("fib", Type::get::<fn(u64) -> u64>(&ctx));
func.add_attributes(&[NoUnwind, ReadNone]);
let value = &func[0];
let entry = func.append("entry");
let on_zero = func.append("on_zero");
let on_one = func.append("on_one");
let default = func.append("default");
let builder = Builder::new(&ctx);
let zero = 0u64.compile(&ctx);
let one = 1u64.compile(&ctx);
builder.position_at_end(entry);
builder.build_switch(value, default, &[
(zero, on_zero),
(one, on_one)
]);
builder.position_at_end(on_zero);
builder.build_ret(zero);
builder.position_at_end(on_one);
builder.build_ret(one);
builder.position_at_end(default);
let two = 2u64.compile(&ctx);
let a = builder.build_sub(value, one);
let b = builder.build_sub(value, two);
let fa = builder.build_tail_call(func, &[a]);
let fb = builder.build_tail_call(func, &[b]);
builder.build_ret(builder.build_add(fa, fb));
module.verify().unwrap();
let ee = JitEngine::new(&module, JitOptions {opt_level: 0}).unwrap();
ee.with_function(func, |fib: extern fn(u64) -> u64| {
for i in 0..10 {
println!("fib {} = {}", i, fib(i))
}
});
}