1 // Copyright 2012 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 use llvm::{AvailableExternallyLinkage, InternalLinkage, SetLinkage};
12 use metadata::csearch;
13 use middle::astencode;
14 use middle::trans::base::{push_ctxt, trans_item, get_item_val, trans_fn};
15 use middle::trans::common::*;
19 use syntax::ast_util::{local_def, PostExpansionMethod};
22 pub fn maybe_instantiate_inline(ccx: &CrateContext, fn_id: ast::DefId)
24 let _icx = push_ctxt("maybe_instantiate_inline");
25 match ccx.external().borrow().find(&fn_id) {
26 Some(&Some(node_id)) => {
28 debug!("maybe_instantiate_inline({}): already inline as node id {}",
29 ty::item_path_str(ccx.tcx(), fn_id), node_id);
30 return local_def(node_id);
33 return fn_id; // Not inlinable
41 csearch::maybe_get_item_ast(
43 |a,b,c,d| astencode::decode_inlined_item(a, b, c, d));
44 return match csearch_result {
45 csearch::not_found => {
46 ccx.external().borrow_mut().insert(fn_id, None);
49 csearch::found(ast::IIItem(item)) => {
50 ccx.external().borrow_mut().insert(fn_id, Some(item.id));
51 ccx.external_srcs().borrow_mut().insert(item.id, fn_id);
53 ccx.stats().n_inlines.set(ccx.stats().n_inlines.get() + 1);
54 trans_item(ccx, &*item);
56 let linkage = match item.node {
57 ast::ItemFn(_, _, _, ref generics, _) => {
58 if generics.is_type_parameterized() {
59 // Generics have no symbol, so they can't be given any
63 if ccx.sess().opts.cg.codegen_units == 1 {
64 // We could use AvailableExternallyLinkage here,
65 // but InternalLinkage allows LLVM to optimize more
66 // aggressively (at the cost of sometimes
70 // With multiple compilation units, duplicated code
71 // is more of a problem. Also, `codegen_units > 1`
72 // means the user is okay with losing some
74 Some(AvailableExternallyLinkage)
78 ast::ItemStatic(_, mutbl, _) => {
79 if !ast_util::static_has_significant_address(mutbl, item.attrs.as_slice()) {
80 // Inlined static items use internal linkage when
81 // possible, so that LLVM will coalesce globals with
82 // identical initializers. (It only does this for
83 // globals with unnamed_addr and either internal or
87 // The address is significant, so we can't create an
88 // internal copy of the static. (The copy would have a
89 // different address from the original.)
90 Some(AvailableExternallyLinkage)
98 let g = get_item_val(ccx, item.id);
99 SetLinkage(g, linkage);
106 csearch::found(ast::IIForeign(item)) => {
107 ccx.external().borrow_mut().insert(fn_id, Some(item.id));
108 ccx.external_srcs().borrow_mut().insert(item.id, fn_id);
111 csearch::found_parent(parent_id, ast::IIItem(item)) => {
112 ccx.external().borrow_mut().insert(parent_id, Some(item.id));
113 ccx.external_srcs().borrow_mut().insert(item.id, parent_id);
117 ast::ItemEnum(_, _) => {
118 let vs_here = ty::enum_variants(ccx.tcx(), local_def(item.id));
119 let vs_there = ty::enum_variants(ccx.tcx(), parent_id);
120 for (here, there) in vs_here.iter().zip(vs_there.iter()) {
121 if there.id == fn_id { my_id = here.id.node; }
122 ccx.external().borrow_mut().insert(there.id, Some(here.id.node));
125 ast::ItemStruct(ref struct_def, _) => {
126 match struct_def.ctor_id {
129 ccx.external().borrow_mut().insert(fn_id, Some(ctor_id));
134 _ => ccx.sess().bug("maybe_instantiate_inline: item has a \
135 non-enum, non-struct parent")
137 trans_item(ccx, &*item);
140 csearch::found_parent(_, _) => {
141 ccx.sess().bug("maybe_get_item_ast returned a found_parent \
142 with a non-item parent");
144 csearch::found(ast::IITraitItem(impl_did, impl_item)) => {
146 ast::ProvidedInlinedTraitItem(mth) |
147 ast::RequiredInlinedTraitItem(mth) => {
148 ccx.external().borrow_mut().insert(fn_id, Some(mth.id));
149 ccx.external_srcs().borrow_mut().insert(mth.id, fn_id);
151 ccx.stats().n_inlines.set(ccx.stats().n_inlines.get() + 1);
156 ast::ProvidedInlinedTraitItem(mth) => {
157 // If this is a default method, we can't look up the
158 // impl type. But we aren't going to translate anyways, so
162 ast::RequiredInlinedTraitItem(mth) => {
163 let impl_tpt = ty::lookup_item_type(ccx.tcx(), impl_did);
164 let unparameterized = impl_tpt.generics.types.is_empty() &&
165 mth.pe_generics().ty_params.is_empty();
168 let llfn = get_item_val(ccx, mth.id);
173 ¶m_substs::empty(),
176 // Use InternalLinkage so LLVM can optimize more
178 SetLinkage(llfn, InternalLinkage);