738 lines
25 KiB
Rust
738 lines
25 KiB
Rust
// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
|
|
// file at the top-level directory of this distribution and at
|
|
// http://rust-lang.org/COPYRIGHT.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
|
|
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
|
|
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
|
|
// option. This file may not be copied, modified, or distributed
|
|
// except according to those terms.
|
|
|
|
//!
|
|
//
|
|
// Handles translation of callees as well as other call-related
|
|
// things. Callees are a superset of normal rust values and sometimes
|
|
// have different representations. In particular, top-level fn items
|
|
// and methods are represented as just a fn ptr and not a full
|
|
// closure.
|
|
|
|
use core::prelude::*;
|
|
|
|
use lib::llvm::ValueRef;
|
|
use middle::trans::base::{get_item_val, trans_external_path};
|
|
use middle::trans::build::*;
|
|
use middle::trans::callee;
|
|
use middle::trans::closure;
|
|
use middle::trans::common::{block, node_id_type_params};
|
|
use middle::trans::datum::*;
|
|
use middle::trans::datum::Datum;
|
|
use middle::trans::inline;
|
|
use middle::trans::meth;
|
|
use middle::trans::monomorphize;
|
|
use middle::typeck;
|
|
use util::common::indenter;
|
|
|
|
use syntax::ast;
|
|
use syntax::print::pprust::{expr_to_str, stmt_to_str, path_to_str};
|
|
use syntax::visit;
|
|
|
|
// Represents a (possibly monomorphized) top-level fn item or method
|
|
// item. Note that this is just the fn-ptr and is not a Rust closure
|
|
// value (which is a pair).
|
|
struct FnData {
|
|
llfn: ValueRef,
|
|
}
|
|
|
|
struct MethodData {
|
|
llfn: ValueRef,
|
|
llself: ValueRef,
|
|
self_ty: ty::t,
|
|
self_mode: ast::rmode
|
|
}
|
|
|
|
enum CalleeData {
|
|
Closure(Datum),
|
|
Fn(FnData),
|
|
Method(MethodData)
|
|
}
|
|
|
|
struct Callee {
|
|
bcx: block,
|
|
data: CalleeData
|
|
}
|
|
|
|
fn trans(bcx: block, expr: @ast::expr) -> Callee {
|
|
let _icx = bcx.insn_ctxt("trans_callee");
|
|
|
|
// pick out special kinds of expressions that can be called:
|
|
match expr.node {
|
|
ast::expr_path(_) => {
|
|
return trans_def(bcx, bcx.def(expr.id), expr);
|
|
}
|
|
ast::expr_field(base, _, _) => {
|
|
match bcx.ccx().maps.method_map.find(expr.id) {
|
|
Some(ref origin) => { // An impl method
|
|
return meth::trans_method_callee(bcx, expr.id,
|
|
base, (*origin));
|
|
}
|
|
None => {} // not a method, just a field
|
|
}
|
|
}
|
|
_ => {}
|
|
}
|
|
|
|
// any other expressions are closures:
|
|
return closure_callee(&expr::trans_to_datum(bcx, expr));
|
|
|
|
fn closure_callee(db: &DatumBlock) -> Callee {
|
|
return Callee {bcx: db.bcx, data: Closure(db.datum)};
|
|
}
|
|
|
|
fn fn_callee(bcx: block, fd: FnData) -> Callee {
|
|
return Callee {bcx: bcx, data: Fn(fd)};
|
|
}
|
|
|
|
fn trans_def(bcx: block, def: ast::def, ref_expr: @ast::expr) -> Callee {
|
|
match def {
|
|
ast::def_fn(did, _) | ast::def_static_method(did, None, _) => {
|
|
fn_callee(bcx, trans_fn_ref(bcx, did, ref_expr.id))
|
|
}
|
|
ast::def_static_method(impl_did, Some(trait_did), _) => {
|
|
fn_callee(bcx, meth::trans_static_method_callee(bcx, impl_did,
|
|
trait_did,
|
|
ref_expr.id))
|
|
}
|
|
ast::def_variant(tid, vid) => {
|
|
// nullary variants are not callable
|
|
assert ty::enum_variant_with_id(bcx.tcx(),
|
|
tid,
|
|
vid).args.len() > 0u;
|
|
fn_callee(bcx, trans_fn_ref(bcx, vid, ref_expr.id))
|
|
}
|
|
ast::def_struct(def_id) => {
|
|
fn_callee(bcx, trans_fn_ref(bcx, def_id, ref_expr.id))
|
|
}
|
|
ast::def_arg(*) |
|
|
ast::def_local(*) |
|
|
ast::def_binding(*) |
|
|
ast::def_upvar(*) |
|
|
ast::def_self(*) => {
|
|
closure_callee(&expr::trans_to_datum(bcx, ref_expr))
|
|
}
|
|
ast::def_mod(*) | ast::def_foreign_mod(*) |
|
|
ast::def_const(*) | ast::def_ty(*) | ast::def_prim_ty(*) |
|
|
ast::def_use(*) | ast::def_typaram_binder(*) |
|
|
ast::def_region(*) | ast::def_label(*) | ast::def_ty_param(*) |
|
|
ast::def_self_ty(*) => {
|
|
bcx.tcx().sess.span_bug(
|
|
ref_expr.span,
|
|
fmt!("Cannot translate def %? \
|
|
to a callable thing!", def));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn trans_fn_ref_to_callee(bcx: block,
|
|
def_id: ast::def_id,
|
|
ref_id: ast::node_id) -> Callee
|
|
{
|
|
Callee {bcx: bcx,
|
|
data: Fn(trans_fn_ref(bcx, def_id, ref_id))}
|
|
}
|
|
|
|
fn trans_fn_ref(bcx: block,
|
|
def_id: ast::def_id,
|
|
ref_id: ast::node_id) -> FnData {
|
|
/*!
|
|
*
|
|
* Translates a reference (with id `ref_id`) to the fn/method
|
|
* with id `def_id` into a function pointer. This may require
|
|
* monomorphization or inlining. */
|
|
|
|
let _icx = bcx.insn_ctxt("trans_fn");
|
|
|
|
let type_params = node_id_type_params(bcx, ref_id);
|
|
|
|
let vtables = node_vtables(bcx, ref_id);
|
|
trans_fn_ref_with_vtables(bcx, def_id, ref_id, type_params, vtables)
|
|
}
|
|
|
|
fn trans_fn_ref_with_vtables_to_callee(bcx: block,
|
|
def_id: ast::def_id,
|
|
ref_id: ast::node_id,
|
|
+type_params: ~[ty::t],
|
|
vtables: Option<typeck::vtable_res>)
|
|
-> Callee
|
|
{
|
|
Callee {bcx: bcx,
|
|
data: Fn(trans_fn_ref_with_vtables(bcx, def_id, ref_id,
|
|
type_params, vtables))}
|
|
}
|
|
|
|
fn trans_fn_ref_with_vtables(
|
|
bcx: block, //
|
|
def_id: ast::def_id, // def id of fn
|
|
ref_id: ast::node_id, // node id of use of fn; may be zero if N/A
|
|
+type_params: ~[ty::t], // values for fn's ty params
|
|
vtables: Option<typeck::vtable_res>)
|
|
-> FnData
|
|
{
|
|
//!
|
|
//
|
|
// Translates a reference to a fn/method item, monomorphizing and
|
|
// inlining as it goes.
|
|
//
|
|
// # Parameters
|
|
//
|
|
// - `bcx`: the current block where the reference to the fn occurs
|
|
// - `def_id`: def id of the fn or method item being referenced
|
|
// - `ref_id`: node id of the reference to the fn/method, if applicable.
|
|
// This parameter may be zero; but, if so, the resulting value may not
|
|
// have the right type, so it must be cast before being used.
|
|
// - `type_params`: values for each of the fn/method's type parameters
|
|
// - `vtables`: values for each bound on each of the type parameters
|
|
|
|
let _icx = bcx.insn_ctxt("trans_fn_with_vtables");
|
|
let ccx = bcx.ccx();
|
|
let tcx = ccx.tcx;
|
|
|
|
debug!("trans_fn_ref_with_vtables(bcx=%s, def_id=%?, ref_id=%?, \
|
|
type_params=%?, vtables=%?)",
|
|
bcx.to_str(), def_id, ref_id,
|
|
type_params.map(|t| bcx.ty_to_str(*t)),
|
|
vtables);
|
|
let _indenter = indenter();
|
|
|
|
// Polytype of the function item (may have type params)
|
|
let fn_tpt = ty::lookup_item_type(tcx, def_id);
|
|
|
|
// Modify the def_id if this is a default method; we want to be
|
|
// monomorphizing the trait's code.
|
|
let (def_id, opt_impl_did) =
|
|
match tcx.provided_method_sources.find(def_id) {
|
|
None => (def_id, None),
|
|
Some(source) => (source.method_id, Some(source.impl_id))
|
|
};
|
|
|
|
// Check whether this fn has an inlined copy and, if so, redirect
|
|
// def_id to the local id of the inlined copy.
|
|
let def_id = {
|
|
if def_id.crate != ast::local_crate {
|
|
let may_translate = opt_impl_did.is_none();
|
|
inline::maybe_instantiate_inline(ccx, def_id, may_translate)
|
|
} else {
|
|
def_id
|
|
}
|
|
};
|
|
|
|
// We must monomorphise if the fn has type parameters, is a rust
|
|
// intrinsic, or is a default method. In particular, if we see an
|
|
// intrinsic that is inlined from a different crate, we want to reemit the
|
|
// intrinsic instead of trying to call it in the other crate.
|
|
let must_monomorphise;
|
|
if type_params.len() > 0 || opt_impl_did.is_some() {
|
|
must_monomorphise = true;
|
|
} else if def_id.crate == ast::local_crate {
|
|
let map_node = session::expect(
|
|
ccx.sess,
|
|
ccx.tcx.items.find(def_id.node),
|
|
|| fmt!("local item should be in ast map"));
|
|
|
|
match map_node {
|
|
ast_map::node_foreign_item(_,
|
|
ast::foreign_abi_rust_intrinsic,
|
|
_) => {
|
|
must_monomorphise = true;
|
|
}
|
|
_ => {
|
|
must_monomorphise = false;
|
|
}
|
|
}
|
|
} else {
|
|
must_monomorphise = false;
|
|
}
|
|
|
|
// Create a monomorphic verison of generic functions
|
|
if must_monomorphise {
|
|
// Should be either intra-crate or inlined.
|
|
assert def_id.crate == ast::local_crate;
|
|
|
|
let mut {val, must_cast} =
|
|
monomorphize::monomorphic_fn(ccx, def_id, type_params,
|
|
vtables, opt_impl_did, Some(ref_id));
|
|
if must_cast && ref_id != 0 {
|
|
// Monotype of the REFERENCE to the function (type params
|
|
// are subst'd)
|
|
let ref_ty = common::node_id_type(bcx, ref_id);
|
|
|
|
val = PointerCast(
|
|
bcx, val, T_ptr(type_of::type_of_fn_from_ty(ccx, ref_ty)));
|
|
}
|
|
return FnData {llfn: val};
|
|
}
|
|
|
|
// Find the actual function pointer.
|
|
let mut val = {
|
|
if def_id.crate == ast::local_crate {
|
|
// Internal reference.
|
|
get_item_val(ccx, def_id.node)
|
|
} else {
|
|
// External reference.
|
|
trans_external_path(ccx, def_id, fn_tpt.ty)
|
|
}
|
|
};
|
|
|
|
return FnData {llfn: val};
|
|
}
|
|
|
|
// ______________________________________________________________________
|
|
// Translating calls
|
|
|
|
fn trans_call(in_cx: block,
|
|
call_ex: @ast::expr,
|
|
f: @ast::expr,
|
|
args: CallArgs,
|
|
id: ast::node_id,
|
|
dest: expr::Dest)
|
|
-> block
|
|
{
|
|
let _icx = in_cx.insn_ctxt("trans_call");
|
|
trans_call_inner(
|
|
in_cx, call_ex.info(), expr_ty(in_cx, f), node_id_type(in_cx, id),
|
|
|cx| trans(cx, f), args, dest, DontAutorefArg)
|
|
}
|
|
|
|
fn trans_method_call(in_cx: block,
|
|
call_ex: @ast::expr,
|
|
rcvr: @ast::expr,
|
|
args: CallArgs,
|
|
dest: expr::Dest)
|
|
-> block {
|
|
let _icx = in_cx.insn_ctxt("trans_method_call");
|
|
trans_call_inner(
|
|
in_cx,
|
|
call_ex.info(),
|
|
node_id_type(in_cx, call_ex.callee_id),
|
|
expr_ty(in_cx, call_ex),
|
|
|cx| {
|
|
match cx.ccx().maps.method_map.find(call_ex.id) {
|
|
Some(ref origin) => {
|
|
meth::trans_method_callee(cx,
|
|
call_ex.callee_id,
|
|
rcvr,
|
|
(*origin))
|
|
}
|
|
None => {
|
|
cx.tcx().sess.span_bug(call_ex.span,
|
|
~"method call expr wasn't in \
|
|
method map")
|
|
}
|
|
}
|
|
},
|
|
args,
|
|
dest,
|
|
DontAutorefArg)
|
|
}
|
|
|
|
fn trans_rtcall_or_lang_call(bcx: block, did: ast::def_id, args: ~[ValueRef],
|
|
dest: expr::Dest) -> block {
|
|
let fty = if did.crate == ast::local_crate {
|
|
ty::node_id_to_type(bcx.ccx().tcx, did.node)
|
|
} else {
|
|
csearch::get_type(bcx.ccx().tcx, did).ty
|
|
};
|
|
let rty = ty::ty_fn_ret(fty);
|
|
return callee::trans_call_inner(
|
|
bcx, None, fty, rty,
|
|
|bcx| trans_fn_ref_with_vtables_to_callee(bcx, did, 0, ~[], None),
|
|
ArgVals(args), dest, DontAutorefArg);
|
|
}
|
|
|
|
fn trans_rtcall_or_lang_call_with_type_params(bcx: block,
|
|
did: ast::def_id,
|
|
args: ~[ValueRef],
|
|
type_params: ~[ty::t],
|
|
dest: expr::Dest) -> block {
|
|
let fty;
|
|
if did.crate == ast::local_crate {
|
|
fty = ty::node_id_to_type(bcx.tcx(), did.node);
|
|
} else {
|
|
fty = csearch::get_type(bcx.tcx(), did).ty;
|
|
}
|
|
|
|
let rty = ty::ty_fn_ret(fty);
|
|
return callee::trans_call_inner(
|
|
bcx, None, fty, rty,
|
|
|bcx| {
|
|
let callee =
|
|
trans_fn_ref_with_vtables_to_callee(bcx, did, 0,
|
|
copy type_params,
|
|
None);
|
|
|
|
let new_llval;
|
|
match callee.data {
|
|
Fn(fn_data) => {
|
|
let substituted = ty::subst_tps(callee.bcx.tcx(),
|
|
type_params,
|
|
None,
|
|
fty);
|
|
let mut llfnty = type_of::type_of(callee.bcx.ccx(),
|
|
substituted);
|
|
llfnty = T_ptr(struct_elt(llfnty, 0));
|
|
new_llval = PointerCast(callee.bcx, fn_data.llfn, llfnty);
|
|
}
|
|
_ => fail
|
|
}
|
|
Callee { bcx: callee.bcx, data: Fn(FnData { llfn: new_llval }) }
|
|
},
|
|
ArgVals(args), dest, DontAutorefArg);
|
|
}
|
|
|
|
fn body_contains_ret(body: ast::blk) -> bool {
|
|
let cx = {mut found: false};
|
|
visit::visit_block(body, cx, visit::mk_vt(@visit::Visitor {
|
|
visit_item: |_i, _cx, _v| { },
|
|
visit_expr: |e: @ast::expr, cx: {mut found: bool}, v| {
|
|
if !cx.found {
|
|
match e.node {
|
|
ast::expr_ret(_) => cx.found = true,
|
|
_ => visit::visit_expr(e, cx, v),
|
|
}
|
|
}
|
|
},
|
|
..*visit::default_visitor()
|
|
}));
|
|
cx.found
|
|
}
|
|
|
|
// See [Note-arg-mode]
|
|
fn trans_call_inner(
|
|
++in_cx: block,
|
|
call_info: Option<node_info>,
|
|
fn_expr_ty: ty::t,
|
|
ret_ty: ty::t,
|
|
get_callee: fn(block) -> Callee,
|
|
args: CallArgs,
|
|
dest: expr::Dest,
|
|
autoref_arg: AutorefArg) -> block
|
|
{
|
|
do base::with_scope(in_cx, call_info, ~"call") |cx| {
|
|
let ret_in_loop = match /*bad*/copy args {
|
|
ArgExprs(args) => {
|
|
args.len() > 0u && match vec::last(args).node {
|
|
ast::expr_loop_body(@{
|
|
node: ast::expr_fn_block(_, ref body, _),
|
|
_
|
|
}) => body_contains_ret((*body)),
|
|
_ => false
|
|
}
|
|
}
|
|
_ => false
|
|
};
|
|
|
|
let callee = get_callee(cx);
|
|
let mut bcx = callee.bcx;
|
|
let ccx = cx.ccx();
|
|
let ret_flag = if ret_in_loop {
|
|
let flag = alloca(bcx, T_bool());
|
|
Store(bcx, C_bool(false), flag);
|
|
Some(flag)
|
|
} else { None };
|
|
|
|
let (llfn, llenv) = unsafe {
|
|
match callee.data {
|
|
Fn(d) => {
|
|
(d.llfn, llvm::LLVMGetUndef(T_opaque_box_ptr(ccx)))
|
|
}
|
|
Method(d) => {
|
|
// Weird but true: we pass self in the *environment* slot!
|
|
let llself = PointerCast(bcx, d.llself,
|
|
T_opaque_box_ptr(ccx));
|
|
(d.llfn, llself)
|
|
}
|
|
Closure(d) => {
|
|
// Closures are represented as (llfn, llclosure) pair:
|
|
// load the requisite values out.
|
|
let pair = d.to_ref_llval(bcx);
|
|
let llfn = GEPi(bcx, pair, [0u, abi::fn_field_code]);
|
|
let llfn = Load(bcx, llfn);
|
|
let llenv = GEPi(bcx, pair, [0u, abi::fn_field_box]);
|
|
let llenv = Load(bcx, llenv);
|
|
(llfn, llenv)
|
|
}
|
|
}
|
|
};
|
|
|
|
let args_res = trans_args(bcx, llenv, /*bad*/copy args, fn_expr_ty,
|
|
dest, ret_flag, autoref_arg);
|
|
bcx = args_res.bcx;
|
|
let mut llargs = /*bad*/copy args_res.args;
|
|
|
|
let llretslot = args_res.retslot;
|
|
|
|
// Now that the arguments have finished evaluating, we need to revoke
|
|
// the cleanup for the self argument, if it exists
|
|
match callee.data {
|
|
Method(d) if d.self_mode == ast::by_copy => {
|
|
revoke_clean(bcx, d.llself);
|
|
}
|
|
_ => {}
|
|
}
|
|
|
|
// Uncomment this to debug calls.
|
|
/*
|
|
io::println(fmt!("calling: %s", bcx.val_str(llfn)));
|
|
for llargs.each |llarg| {
|
|
io::println(fmt!("arg: %s", bcx.val_str(*llarg)));
|
|
}
|
|
io::println("---");
|
|
*/
|
|
|
|
// If the block is terminated, then one or more of the args
|
|
// has type _|_. Since that means it diverges, the code for
|
|
// the call itself is unreachable.
|
|
bcx = base::invoke(bcx, llfn, llargs);
|
|
match dest { // drop the value if it is not being saved.
|
|
expr::Ignore => {
|
|
unsafe {
|
|
if llvm::LLVMIsUndef(llretslot) != lib::llvm::True {
|
|
bcx = glue::drop_ty(bcx, llretslot, ret_ty);
|
|
}
|
|
}
|
|
}
|
|
expr::SaveIn(_) => { }
|
|
}
|
|
if ty::type_is_bot(ret_ty) {
|
|
Unreachable(bcx);
|
|
} else if ret_in_loop {
|
|
bcx = do with_cond(bcx, Load(bcx, ret_flag.get())) |bcx| {
|
|
do option::iter(© bcx.fcx.loop_ret) |lret| {
|
|
Store(bcx, C_bool(true), lret.flagptr);
|
|
Store(bcx, C_bool(false), bcx.fcx.llretptr);
|
|
}
|
|
base::cleanup_and_leave(bcx, None, Some(bcx.fcx.llreturn));
|
|
Unreachable(bcx);
|
|
bcx
|
|
}
|
|
}
|
|
bcx
|
|
}
|
|
}
|
|
|
|
|
|
enum CallArgs {
|
|
ArgExprs(~[@ast::expr]),
|
|
ArgVals(~[ValueRef])
|
|
}
|
|
|
|
fn trans_args(cx: block,
|
|
llenv: ValueRef,
|
|
+args: CallArgs,
|
|
fn_ty: ty::t,
|
|
dest: expr::Dest,
|
|
ret_flag: Option<ValueRef>,
|
|
+autoref_arg: AutorefArg)
|
|
-> {bcx: block, args: ~[ValueRef], retslot: ValueRef}
|
|
{
|
|
let _icx = cx.insn_ctxt("trans_args");
|
|
let mut temp_cleanups = ~[];
|
|
let arg_tys = ty::ty_fn_args(fn_ty);
|
|
let mut llargs: ~[ValueRef] = ~[];
|
|
|
|
let mut bcx = cx;
|
|
|
|
let retty = ty::ty_fn_ret(fn_ty);
|
|
|
|
// Arg 0: Output pointer.
|
|
let llretslot = match dest {
|
|
expr::SaveIn(dst) => dst,
|
|
expr::Ignore => {
|
|
if ty::type_is_nil(retty) {
|
|
unsafe {
|
|
llvm::LLVMGetUndef(T_ptr(T_nil()))
|
|
}
|
|
} else {
|
|
alloc_ty(bcx, retty)
|
|
}
|
|
}
|
|
};
|
|
llargs.push(llretslot);
|
|
|
|
// Arg 1: Env (closure-bindings / self value)
|
|
llargs.push(llenv);
|
|
|
|
// ... then explicit args.
|
|
|
|
// First we figure out the caller's view of the types of the arguments.
|
|
// This will be needed if this is a generic call, because the callee has
|
|
// to cast her view of the arguments to the caller's view.
|
|
match args {
|
|
ArgExprs(arg_exprs) => {
|
|
let last = arg_exprs.len() - 1u;
|
|
for vec::eachi(arg_exprs) |i, arg_expr| {
|
|
let arg_val = unpack_result!(bcx, {
|
|
trans_arg_expr(bcx, arg_tys[i], *arg_expr, &mut temp_cleanups,
|
|
if i == last { ret_flag } else { None },
|
|
autoref_arg)
|
|
});
|
|
llargs.push(arg_val);
|
|
}
|
|
}
|
|
ArgVals(vs) => {
|
|
llargs.push_all(vs);
|
|
}
|
|
}
|
|
|
|
// now that all arguments have been successfully built, we can revoke any
|
|
// temporary cleanups, as they are only needed if argument construction
|
|
// should fail (for example, cleanup of copy mode args).
|
|
for vec::each(temp_cleanups) |c| {
|
|
revoke_clean(bcx, *c)
|
|
}
|
|
|
|
return {bcx: bcx, args: llargs, retslot: llretslot};
|
|
}
|
|
|
|
enum AutorefArg {
|
|
DontAutorefArg,
|
|
DoAutorefArg
|
|
}
|
|
|
|
// temp_cleanups: cleanups that should run only if failure occurs before the
|
|
// call takes place:
|
|
fn trans_arg_expr(bcx: block,
|
|
formal_ty: ty::arg,
|
|
arg_expr: @ast::expr,
|
|
temp_cleanups: &mut ~[ValueRef],
|
|
ret_flag: Option<ValueRef>,
|
|
+autoref_arg: AutorefArg)
|
|
-> Result
|
|
{
|
|
let _icx = bcx.insn_ctxt("trans_arg_expr");
|
|
let ccx = bcx.ccx();
|
|
|
|
debug!("trans_arg_expr(formal_ty=(%?,%s), arg_expr=%s, \
|
|
ret_flag=%?)",
|
|
formal_ty.mode, bcx.ty_to_str(formal_ty.ty),
|
|
bcx.expr_to_str(arg_expr),
|
|
ret_flag.map(|v| bcx.val_str(*v)));
|
|
let _indenter = indenter();
|
|
|
|
// translate the arg expr to a datum
|
|
let arg_datumblock = match ret_flag {
|
|
None => expr::trans_to_datum(bcx, arg_expr),
|
|
|
|
// If there is a ret_flag, this *must* be a loop body
|
|
Some(_) => {
|
|
match arg_expr.node {
|
|
ast::expr_loop_body(
|
|
// XXX: Bad copy.
|
|
blk@@{
|
|
node: ast::expr_fn_block(copy decl, ref body, cap),
|
|
_
|
|
}) =>
|
|
{
|
|
let scratch_ty = expr_ty(bcx, blk);
|
|
let scratch = alloc_ty(bcx, scratch_ty);
|
|
let arg_ty = expr_ty(bcx, arg_expr);
|
|
let proto = ty::ty_fn_proto(arg_ty);
|
|
let bcx = closure::trans_expr_fn(
|
|
bcx, proto, decl, /*bad*/copy *body, blk.id, cap,
|
|
Some(ret_flag), expr::SaveIn(scratch));
|
|
DatumBlock {bcx: bcx,
|
|
datum: Datum {val: scratch,
|
|
ty: scratch_ty,
|
|
mode: ByRef,
|
|
source: FromRvalue}}
|
|
}
|
|
_ => {
|
|
bcx.sess().impossible_case(
|
|
arg_expr.span, ~"ret_flag with non-loop-\
|
|
body expr");
|
|
}
|
|
}
|
|
}
|
|
};
|
|
let mut arg_datum = arg_datumblock.datum;
|
|
let mut bcx = arg_datumblock.bcx;
|
|
|
|
debug!(" arg datum: %s", arg_datum.to_str(bcx.ccx()));
|
|
|
|
// finally, deal with the various modes
|
|
let arg_mode = ty::resolved_mode(ccx.tcx, formal_ty.mode);
|
|
let mut val;
|
|
if ty::type_is_bot(arg_datum.ty) {
|
|
// For values of type _|_, we generate an
|
|
// "undef" value, as such a value should never
|
|
// be inspected. It's important for the value
|
|
// to have type lldestty (the callee's expected type).
|
|
let llformal_ty = type_of::type_of(ccx, formal_ty.ty);
|
|
unsafe {
|
|
val = llvm::LLVMGetUndef(llformal_ty);
|
|
}
|
|
} else {
|
|
// FIXME(#3548) use the adjustments table
|
|
match autoref_arg {
|
|
DoAutorefArg => { val = arg_datum.to_ref_llval(bcx); }
|
|
DontAutorefArg => {
|
|
match arg_mode {
|
|
ast::by_ref => {
|
|
val = arg_datum.to_ref_llval(bcx);
|
|
}
|
|
|
|
ast::by_val => {
|
|
// NB: avoid running the take glue.
|
|
val = arg_datum.to_value_llval(bcx);
|
|
}
|
|
|
|
ast::by_copy | ast::by_move => {
|
|
let scratch = scratch_datum(bcx, arg_datum.ty, false);
|
|
|
|
if arg_mode == ast::by_move {
|
|
// NDM---Doesn't seem like this should be
|
|
// necessary
|
|
if !arg_datum.store_will_move() {
|
|
bcx.sess().span_bug(
|
|
arg_expr.span,
|
|
fmt!("move mode but datum will not \
|
|
store: %s",
|
|
arg_datum.to_str(bcx.ccx())));
|
|
}
|
|
}
|
|
|
|
arg_datum.store_to_datum(bcx, INIT, scratch);
|
|
|
|
// Technically, ownership of val passes to the callee.
|
|
// However, we must cleanup should we fail before the
|
|
// callee is actually invoked.
|
|
scratch.add_clean(bcx);
|
|
temp_cleanups.push(scratch.val);
|
|
|
|
match arg_datum.appropriate_mode() {
|
|
ByValue => {
|
|
val = Load(bcx, scratch.val);
|
|
}
|
|
ByRef => {
|
|
val = scratch.val;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if formal_ty.ty != arg_datum.ty {
|
|
// this could happen due to e.g. subtyping
|
|
let llformal_ty = type_of::type_of_explicit_arg(ccx, formal_ty);
|
|
debug!("casting actual type (%s) to match formal (%s)",
|
|
bcx.val_str(val), bcx.llty_str(llformal_ty));
|
|
val = PointerCast(bcx, val, llformal_ty);
|
|
}
|
|
}
|
|
|
|
debug!("--- trans_arg_expr passing %s", val_str(bcx.ccx().tn, val));
|
|
return rslt(bcx, val);
|
|
}
|
|
|