Files
wasmtime/lib/simplejit/examples/simplejit-minimal.rs
Dan Gohman 8d6a8e9069 Remove Module's finalize_function and finalize_data. (#519)
* Remove `Module`'s `finalize_function` and `finalize_data`.

Remove the ability to finalize individiual functions and data objects,
and instead just provide a way to finalize everything that's been
defined but not yet finalized. This allows SimpleJIT to share an
allocation between multiple functions without having to worry about
individual functions being finalized and needing to be published
without the other functions in the same allocation.

Users of the return values of `Module`'s `finalize_function` and
`finalize_data` should now use `get_finalized_function` and
`get_finalized_data` to obtain these values.
2018-09-21 20:13:33 -07:00

83 lines
2.6 KiB
Rust

extern crate cranelift;
extern crate cranelift_module;
extern crate cranelift_simplejit;
use cranelift::prelude::*;
use cranelift_module::{Linkage, Module};
use cranelift_simplejit::{SimpleJITBackend, SimpleJITBuilder};
use std::mem;
fn main() {
let mut module: Module<SimpleJITBackend> = Module::new(SimpleJITBuilder::new());
let mut ctx = module.make_context();
let mut func_ctx = FunctionBuilderContext::new();
let mut sig_a = module.make_signature();
sig_a.params.push(AbiParam::new(types::I32));
sig_a.returns.push(AbiParam::new(types::I32));
let mut sig_b = module.make_signature();
sig_b.returns.push(AbiParam::new(types::I32));
let func_a = module
.declare_function("a", Linkage::Local, &sig_a)
.unwrap();
let func_b = module
.declare_function("b", Linkage::Local, &sig_b)
.unwrap();
ctx.func.signature = sig_a;
ctx.func.name = ExternalName::user(0, func_a.index() as u32);
{
let mut bcx: FunctionBuilder = FunctionBuilder::new(&mut ctx.func, &mut func_ctx);
let ebb = bcx.create_ebb();
bcx.switch_to_block(ebb);
bcx.append_ebb_params_for_function_params(ebb);
let param = bcx.ebb_params(ebb)[0];
let cst = bcx.ins().iconst(types::I32, 37);
let add = bcx.ins().iadd(cst, param);
bcx.ins().return_(&[add]);
bcx.seal_all_blocks();
bcx.finalize();
}
module.define_function(func_a, &mut ctx).unwrap();
module.clear_context(&mut ctx);
ctx.func.signature = sig_b;
ctx.func.name = ExternalName::user(0, func_b.index() as u32);
{
let mut bcx: FunctionBuilder = FunctionBuilder::new(&mut ctx.func, &mut func_ctx);
let ebb = bcx.create_ebb();
bcx.switch_to_block(ebb);
let local_func = module.declare_func_in_func(func_a, &mut bcx.func);
let arg = bcx.ins().iconst(types::I32, 5);
let call = bcx.ins().call(local_func, &[arg]);
let value = {
let results = bcx.inst_results(call);
assert_eq!(results.len(), 1);
results[0].clone()
};
bcx.ins().return_(&[value]);
bcx.seal_all_blocks();
bcx.finalize();
}
module.define_function(func_b, &mut ctx).unwrap();
module.clear_context(&mut ctx);
// Perform linking.
module.finalize_definitions();
// Get a raw pointer to the generated code.
let code_b = module.get_finalized_function(func_b);
// Cast it to a rust function pointer type.
let ptr_b = unsafe { mem::transmute::<_, fn() -> u32>(code_b) };
// Call it!
let res = ptr_b();
assert_eq!(res, 42);
}