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

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use common::*;
use syntax::ast;
use syntax::ast_util::local_def;
use syntax::ast_map::{path, path_mod, path_name};
use base::{trans_item, get_item_val, no_self, self_arg, trans_fn,
impl_self, decl_internal_cdecl_fn,
set_inline_hint_if_appr, set_inline_hint,
trans_enum_variant, trans_class_ctor, trans_class_dtor,
get_insn_ctxt};
use syntax::parse::token::special_idents;
use type_of::type_of_fn_from_ty;
use back::link::mangle_exported_name;
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use middle::ty::{FnTyBase, FnMeta, FnSig};
fn monomorphic_fn(ccx: @crate_ctxt,
fn_id: ast::def_id,
real_substs: ~[ty::t],
vtables: Option<typeck::vtable_res>,
ref_id: Option<ast::node_id>)
-> {val: ValueRef, must_cast: bool}
{
let _icx = ccx.insn_ctxt("monomorphic_fn");
let mut must_cast = false;
let substs = vec::map(real_substs, |t| {
match normalize_for_monomorphization(ccx.tcx, t) {
Some(t) => { must_cast = true; t }
None => t
}
});
for real_substs.each() |s| { assert !ty::type_has_params(s); }
for substs.each() |s| { assert !ty::type_has_params(s); }
let param_uses = type_use::type_uses_for(ccx, fn_id, substs.len());
let hash_id = make_mono_id(ccx, fn_id, substs, vtables, Some(param_uses));
if vec::any(hash_id.params,
|p| match p { mono_precise(_, _) => false, _ => true }) {
must_cast = true;
}
#debug["monomorphic_fn(fn_id=%? (%s), real_substs=%?, substs=%?, \
hash_id = %?",
fn_id, ty::item_path_str(ccx.tcx, fn_id),
real_substs.map(|s| ty_to_str(ccx.tcx, s)),
substs.map(|s| ty_to_str(ccx.tcx, s)), hash_id];
match ccx.monomorphized.find(hash_id) {
Some(val) => {
debug!("leaving monomorphic fn %s",
ty::item_path_str(ccx.tcx, fn_id));
return {val: val, must_cast: must_cast};
}
None => ()
}
let tpt = ty::lookup_item_type(ccx.tcx, fn_id);
let mut llitem_ty = tpt.ty;
let map_node = session::expect(ccx.sess, ccx.tcx.items.find(fn_id.node),
|| fmt!("While monomorphizing %?, couldn't find it in the item map \
(may have attempted to monomorphize an item defined in a different \
crate?)", fn_id));
// Get the path so that we can create a symbol
let (pt, name, span) = match map_node {
ast_map::node_item(i, pt) => (pt, i.ident, i.span),
ast_map::node_variant(v, enm, pt) => (pt, v.node.name, enm.span),
ast_map::node_method(m, _, pt) => (pt, m.ident, m.span),
ast_map::node_foreign_item(i, ast::foreign_abi_rust_intrinsic, pt)
=> (pt, i.ident, i.span),
ast_map::node_foreign_item(*) => {
// Foreign externs don't have to be monomorphized.
return {val: get_item_val(ccx, fn_id.node),
must_cast: true};
}
ast_map::node_ctor(nm, _, ct, _, pt) => (pt, nm, ct.span),
ast_map::node_dtor(_, dtor, _, pt) =>
(pt, special_idents::dtor, dtor.span),
ast_map::node_trait_method(*) => {
ccx.tcx.sess.bug(~"Can't monomorphize a trait method")
}
ast_map::node_expr(*) => {
ccx.tcx.sess.bug(~"Can't monomorphize an expr")
}
ast_map::node_stmt(*) => {
ccx.tcx.sess.bug(~"Can't monomorphize a stmt")
}
ast_map::node_export(*) => {
ccx.tcx.sess.bug(~"Can't monomorphize an export")
}
ast_map::node_arg(*) => ccx.tcx.sess.bug(~"Can't monomorphize an arg"),
ast_map::node_block(*) => {
ccx.tcx.sess.bug(~"Can't monomorphize a block")
}
ast_map::node_local(*) => {
ccx.tcx.sess.bug(~"Can't monomorphize a local")
}
};
let mono_ty = ty::subst_tps(ccx.tcx, substs, llitem_ty);
let llfty = type_of_fn_from_ty(ccx, mono_ty);
ccx.stats.n_monos += 1;
let depth = option::get_default(ccx.monomorphizing.find(fn_id), 0u);
// Random cut-off -- code that needs to instantiate the same function
// recursively more than ten times can probably safely be assumed to be
// causing an infinite expansion.
if depth > 10u {
ccx.sess.span_fatal(
span, ~"overly deep expansion of inlined function");
}
ccx.monomorphizing.insert(fn_id, depth + 1u);
let pt = vec::append(*pt,
~[path_name(ccx.names(ccx.sess.str_of(name)))]);
let s = mangle_exported_name(ccx, pt, mono_ty);
let mk_lldecl = || {
let lldecl = decl_internal_cdecl_fn(ccx.llmod, s, llfty);
ccx.monomorphized.insert(hash_id, lldecl);
lldecl
};
let psubsts = Some({tys: substs, vtables: vtables, bounds: tpt.bounds});
let lldecl = match map_node {
ast_map::node_item(i@@{node: ast::item_fn(decl, _, _, body), _}, _) => {
let d = mk_lldecl();
set_inline_hint_if_appr(i.attrs, d);
trans_fn(ccx, pt, decl, body, d, no_self, psubsts, fn_id.node);
d
}
ast_map::node_item(*) => {
ccx.tcx.sess.bug(~"Can't monomorphize this kind of item")
}
ast_map::node_foreign_item(i, _, _) => {
let d = mk_lldecl();
foreign::trans_intrinsic(ccx, d, i, pt, option::get(psubsts),
ref_id);
d
}
ast_map::node_variant(v, enum_item, _) => {
let tvs = ty::enum_variants(ccx.tcx, local_def(enum_item.id));
let this_tv = option::get(vec::find(*tvs, |tv| {
tv.id.node == fn_id.node}));
let d = mk_lldecl();
set_inline_hint(d);
match v.node.kind {
ast::tuple_variant_kind(args) => {
trans_enum_variant(ccx, enum_item.id, v, args,
this_tv.disr_val, (*tvs).len() == 1u,
psubsts, d);
}
ast::struct_variant_kind(_) =>
ccx.tcx.sess.bug(~"can't monomorphize struct variants"),
ast::enum_variant_kind(_) =>
ccx.tcx.sess.bug(~"can't monomorphize enum variants")
}
d
}
ast_map::node_method(mth, _, _) => {
let d = mk_lldecl();
set_inline_hint_if_appr(mth.attrs, d);
meth::trans_method(ccx, pt, mth, psubsts, d);
d
}
ast_map::node_ctor(_, tps, ctor, parent_id, _) => {
// ctors don't have attrs, at least not right now
let d = mk_lldecl();
let tp_tys = ty::ty_params_to_tys(ccx.tcx, tps);
trans_class_ctor(ccx, pt, ctor.node.dec, ctor.node.body, d,
option::get_default(psubsts,
{tys:tp_tys, vtables: None, bounds: @~[]}),
fn_id.node, parent_id, ctor.span);
d
}
ast_map::node_dtor(_, dtor, _, pt) => {
let parent_id = match ty::ty_to_def_id(ty::node_id_to_type(ccx.tcx,
dtor.node.self_id)) {
Some(did) => did,
None => ccx.sess.span_bug(dtor.span, ~"Bad self ty in \
dtor")
};
trans_class_dtor(ccx, *pt, dtor.node.body,
dtor.node.id, psubsts, Some(hash_id), parent_id)
}
// Ugh -- but this ensures any new variants won't be forgotten
ast_map::node_expr(*) |
ast_map::node_stmt(*) |
ast_map::node_trait_method(*) |
ast_map::node_export(*) |
ast_map::node_arg(*) |
ast_map::node_block(*) |
ast_map::node_local(*) => {
ccx.tcx.sess.bug(fmt!("Can't monomorphize a %?", map_node))
}
};
ccx.monomorphizing.insert(fn_id, depth);
debug!("leaving monomorphic fn %s", ty::item_path_str(ccx.tcx, fn_id));
{val: lldecl, must_cast: must_cast}
}
fn normalize_for_monomorphization(tcx: ty::ctxt, ty: ty::t) -> Option<ty::t> {
// FIXME[mono] could do this recursively. is that worthwhile? (#2529)
match ty::get(ty).sty {
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ty::ty_box(*) => {
Some(ty::mk_opaque_box(tcx))
}
ty::ty_fn(ref fty) => {
Some(ty::mk_fn(
tcx,
FnTyBase {meta: FnMeta {purity: ast::impure_fn,
proto: fty.meta.proto,
bounds: @~[],
ret_style: ast::return_val},
sig: FnSig {inputs: ~[],
output: ty::mk_nil(tcx)}}))
}
ty::ty_trait(_, _, _) => {
let box_proto = ty::proto_vstore(ty::vstore_box);
Some(ty::mk_fn(
tcx,
FnTyBase {meta: FnMeta {purity: ast::impure_fn,
proto: box_proto,
bounds: @~[],
ret_style: ast::return_val},
sig: FnSig {inputs: ~[],
output: ty::mk_nil(tcx)}}))
}
ty::ty_ptr(_) => {
Some(ty::mk_uint(tcx))
}
_ => {
None
}
}
}
fn make_mono_id(ccx: @crate_ctxt, item: ast::def_id, substs: ~[ty::t],
vtables: Option<typeck::vtable_res>,
param_uses: Option<~[type_use::type_uses]>) -> mono_id {
let precise_param_ids = match vtables {
Some(vts) => {
let bounds = ty::lookup_item_type(ccx.tcx, item).bounds;
let mut i = 0u;
vec::map2(*bounds, substs, |bounds, subst| {
let mut v = ~[];
for vec::each(*bounds) |bound| {
match bound {
ty::bound_trait(_) => {
vec::push(v, meth::vtable_id(ccx, vts[i]));
i += 1u;
}
_ => ()
}
}
(subst, if v.len() > 0u { Some(v) } else { None })
})
}
None => {
vec::map(substs, |subst| (subst, None))
}
};
let param_ids = match param_uses {
Some(uses) => {
vec::map2(precise_param_ids, uses, |id, uses| {
match id {
(a, b@Some(_)) => mono_precise(a, b),
(subst, None) => {
if uses == 0u { mono_any }
else if uses == type_use::use_repr &&
!ty::type_needs_drop(ccx.tcx, subst) {
let llty = type_of::type_of(ccx, subst);
let size = shape::llsize_of_real(ccx, llty);
let align = shape::llalign_of_pref(ccx, llty);
// Special value for nil to prevent problems with undef
// return pointers.
if size == 1u && ty::type_is_nil(subst) {
mono_repr(0u, 0u)
} else { mono_repr(size, align) }
} else { mono_precise(subst, None) }
}
}
})
}
None => precise_param_ids.map(|x| { let (a, b) = x;
mono_precise(a, b) })
};
@{def: item, params: param_ids}
}