Add addition example

Author: TomBebbington

examples/add.rs

@@ -0,0 +1,21 @@
+extern crate llvm;
+use llvm::*;
+use llvm::Attribute::*;
+fn main() {
+    let ctx = Context::new();
+    let module = Module::new("add", &ctx);
+    let func = module.add_function("add", Type::get::<fn(f64, f64) -> f64>(&ctx));
+    func.add_attributes(&[NoUnwind, ReadNone]);
+    let entry = func.append("entry");
+    let builder = Builder::new(&ctx);
+    builder.position_at_end(entry);
+    let a = &func[0];
+    let b = &func[1];
+    let value = builder.build_add(a, b);
+    builder.build_ret(value);
+    module.verify().unwrap();
+    let ee = JitEngine::new(&module, JitOptions {opt_level: 3}).unwrap();
+    ee.with_function(func, |add:extern fn((f64, f64)) -> f64| {
+        println!("{} + {} = {}", 1., 2., add((1., 2.)));
+    });
+}