rust/src/rustc/middle/trans/uniq.rs

67 lines
2.2 KiB
Rust

import syntax::ast;
import lib::llvm::ValueRef;
import common::*;
import build::*;
import base::*;
import shape::llsize_of;
export trans_uniq, make_free_glue, autoderef, duplicate;
fn trans_uniq(bcx: block, contents: @ast::expr,
node_id: ast::node_id, dest: dest) -> block {
let _icx = bcx.insn_ctxt("uniq::trans_uniq");
let uniq_ty = node_id_type(bcx, node_id);
let contents_ty = content_ty(uniq_ty);
let {box, body} = malloc_unique(bcx, contents_ty);
add_clean_free(bcx, box, true);
let bcx = trans_expr_save_in(bcx, contents, body);
revoke_clean(bcx, box);
ret store_in_dest(bcx, box, dest);
}
fn make_free_glue(bcx: block, vptr: ValueRef, t: ty::t)
-> block {
let _icx = bcx.insn_ctxt("uniq::make_free_glue");
with_cond(bcx, IsNotNull(bcx, vptr)) {|bcx|
let content_ty = content_ty(t);
let body_ptr = opaque_box_body(bcx, content_ty, vptr);
let bcx = drop_ty(bcx, body_ptr, content_ty);
trans_unique_free(bcx, vptr)
}
}
fn content_ty(t: ty::t) -> ty::t {
alt ty::get(t).struct {
ty::ty_uniq({ty: ct, _}) { ct }
_ { core::unreachable(); }
}
}
fn autoderef(bcx: block, v: ValueRef, t: ty::t) -> {v: ValueRef, t: ty::t} {
let content_ty = content_ty(t);
let v = opaque_box_body(bcx, content_ty, v);
ret {v: v, t: content_ty};
}
fn duplicate(bcx: block, v: ValueRef, t: ty::t) -> result {
let _icx = bcx.insn_ctxt("uniq::duplicate");
let content_ty = content_ty(t);
let {box: dst_box, body: dst_body} = malloc_unique(bcx, content_ty);
let src_box = v;
let src_body = opaque_box_body(bcx, content_ty, src_box);
let src_body = load_if_immediate(bcx, src_body, content_ty);
#debug("ST: %?", val_str(bcx.ccx().tn, src_body));
#debug("DT: %?", val_str(bcx.ccx().tn, dst_body));
let bcx = copy_val(bcx, INIT, dst_body, src_body, content_ty);
let src_tydesc_ptr = GEPi(bcx, src_box,
[0u, back::abi::box_field_tydesc]);
let dst_tydesc_ptr = GEPi(bcx, dst_box,
[0u, back::abi::box_field_tydesc]);
let td = Load(bcx, src_tydesc_ptr);
Store(bcx, td, dst_tydesc_ptr);
ret rslt(bcx, dst_box);
}