rust/src/librustc/middle/trans/reflect.rs

419 lines
16 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.
use back::link::mangle_internal_name_by_path_and_seq;
use lib::llvm::{ValueRef, llvm};
use middle::trans::adt;
use middle::trans::base::*;
use middle::trans::build::*;
use middle::trans::callee::ArgVals;
use middle::trans::callee;
use middle::trans::common::*;
use middle::trans::datum::*;
use middle::trans::glue;
use middle::trans::machine;
use middle::trans::meth;
use middle::trans::type_::Type;
use middle::trans::type_of::*;
use middle::ty;
use util::ppaux::ty_to_str;
use arena::TypedArena;
use std::libc::c_uint;
use std::option::{Some,None};
use std::vec;
use syntax::ast::DefId;
use syntax::ast;
use syntax::ast_map;
use syntax::parse::token::{InternedString, special_idents};
use syntax::parse::token;
pub struct Reflector<'a> {
visitor_val: ValueRef,
visitor_methods: @~[@ty::Method],
final_bcx: &'a Block<'a>,
tydesc_ty: Type,
bcx: &'a Block<'a>
}
impl<'a> Reflector<'a> {
pub fn c_uint(&mut self, u: uint) -> ValueRef {
C_uint(self.bcx.ccx(), u)
}
pub fn c_int(&mut self, i: int) -> ValueRef {
C_int(self.bcx.ccx(), i)
}
pub fn c_bool(&mut self, b: bool) -> ValueRef {
C_bool(b)
}
pub fn c_slice(&mut self, s: InternedString) -> ValueRef {
// We're careful to not use first class aggregates here because that
// will kick us off fast isel. (Issue #4352.)
let bcx = self.bcx;
let str_vstore = ty::vstore_slice(ty::ReStatic);
let str_ty = ty::mk_str(bcx.tcx(), str_vstore);
let scratch = rvalue_scratch_datum(bcx, str_ty, "");
let len = C_uint(bcx.ccx(), s.get().len());
let c_str = PointerCast(bcx, C_cstr(bcx.ccx(), s), Type::i8p());
Store(bcx, c_str, GEPi(bcx, scratch.val, [ 0, 0 ]));
Store(bcx, len, GEPi(bcx, scratch.val, [ 0, 1 ]));
scratch.val
}
pub fn c_size_and_align(&mut self, t: ty::t) -> ~[ValueRef] {
let tr = type_of(self.bcx.ccx(), t);
let s = machine::llsize_of_real(self.bcx.ccx(), tr);
let a = machine::llalign_of_min(self.bcx.ccx(), tr);
return ~[self.c_uint(s as uint),
self.c_uint(a as uint)];
}
pub fn c_tydesc(&mut self, t: ty::t) -> ValueRef {
let bcx = self.bcx;
let static_ti = get_tydesc(bcx.ccx(), t);
glue::lazily_emit_visit_glue(bcx.ccx(), static_ti);
PointerCast(bcx, static_ti.tydesc, self.tydesc_ty.ptr_to())
}
pub fn c_mt(&mut self, mt: &ty::mt) -> ~[ValueRef] {
~[self.c_uint(mt.mutbl as uint),
self.c_tydesc(mt.ty)]
}
pub fn visit(&mut self, ty_name: &str, args: &[ValueRef]) {
let fcx = self.bcx.fcx;
let tcx = self.bcx.tcx();
let mth_idx = ty::method_idx(
token::str_to_ident(~"visit_" + ty_name),
*self.visitor_methods).expect(format!("couldn't find visit method \
for {}", ty_name));
let mth_ty =
ty::mk_bare_fn(tcx, self.visitor_methods[mth_idx].fty.clone());
let v = self.visitor_val;
debug!("passing {} args:", args.len());
let mut bcx = self.bcx;
for (i, a) in args.iter().enumerate() {
debug!("arg {}: {}", i, bcx.val_to_str(*a));
}
let bool_ty = ty::mk_bool();
let result = unpack_result!(bcx, callee::trans_call_inner(
self.bcx, None, mth_ty, bool_ty,
|bcx, _| meth::trans_trait_callee_from_llval(bcx,
mth_ty,
mth_idx,
v),
ArgVals(args), None));
let result = bool_to_i1(bcx, result);
let next_bcx = fcx.new_temp_block("next");
CondBr(bcx, result, next_bcx.llbb, self.final_bcx.llbb);
self.bcx = next_bcx
}
pub fn bracketed(&mut self,
bracket_name: &str,
extra: &[ValueRef],
inner: |&mut Reflector|) {
self.visit("enter_" + bracket_name, extra);
inner(self);
self.visit("leave_" + bracket_name, extra);
}
pub fn vstore_name_and_extra(&mut self,
t: ty::t,
vstore: ty::vstore)
-> (~str, ~[ValueRef]) {
match vstore {
ty::vstore_fixed(n) => {
let extra = vec::append(~[self.c_uint(n)],
self.c_size_and_align(t));
(~"fixed", extra)
}
ty::vstore_slice(_) => (~"slice", ~[]),
ty::vstore_uniq => (~"uniq", ~[]),
}
}
pub fn leaf(&mut self, name: &str) {
self.visit(name, []);
}
// Entrypoint
pub fn visit_ty(&mut self, t: ty::t) {
let bcx = self.bcx;
let tcx = bcx.ccx().tcx;
debug!("reflect::visit_ty {}", ty_to_str(bcx.ccx().tcx, t));
match ty::get(t).sty {
ty::ty_bot => self.leaf("bot"),
ty::ty_nil => self.leaf("nil"),
ty::ty_bool => self.leaf("bool"),
ty::ty_char => self.leaf("char"),
ty::ty_int(ast::TyI) => self.leaf("int"),
ty::ty_int(ast::TyI8) => self.leaf("i8"),
ty::ty_int(ast::TyI16) => self.leaf("i16"),
ty::ty_int(ast::TyI32) => self.leaf("i32"),
ty::ty_int(ast::TyI64) => self.leaf("i64"),
ty::ty_uint(ast::TyU) => self.leaf("uint"),
ty::ty_uint(ast::TyU8) => self.leaf("u8"),
ty::ty_uint(ast::TyU16) => self.leaf("u16"),
ty::ty_uint(ast::TyU32) => self.leaf("u32"),
ty::ty_uint(ast::TyU64) => self.leaf("u64"),
ty::ty_float(ast::TyF32) => self.leaf("f32"),
ty::ty_float(ast::TyF64) => self.leaf("f64"),
ty::ty_unboxed_vec(ref mt) => {
let values = self.c_mt(mt);
self.visit("vec", values)
}
// Should rename to str_*/vec_*.
ty::ty_str(vst) => {
let (name, extra) = self.vstore_name_and_extra(t, vst);
self.visit(~"estr_" + name, extra)
}
ty::ty_vec(ref mt, vst) => {
let (name, extra) = self.vstore_name_and_extra(t, vst);
let extra = extra + self.c_mt(mt);
self.visit(~"evec_" + name, extra)
}
// Should remove mt from box and uniq.
ty::ty_box(typ) => {
let extra = self.c_mt(&ty::mt {
ty: typ,
mutbl: ast::MutImmutable,
});
self.visit("box", extra)
}
ty::ty_uniq(typ) => {
let extra = self.c_mt(&ty::mt {
ty: typ,
mutbl: ast::MutImmutable,
});
self.visit("uniq", extra)
}
ty::ty_ptr(ref mt) => {
let extra = self.c_mt(mt);
self.visit("ptr", extra)
}
ty::ty_rptr(_, ref mt) => {
let extra = self.c_mt(mt);
self.visit("rptr", extra)
}
ty::ty_tup(ref tys) => {
let extra = ~[self.c_uint(tys.len())]
+ self.c_size_and_align(t);
self.bracketed("tup", extra, |this| {
for (i, t) in tys.iter().enumerate() {
let extra = ~[this.c_uint(i), this.c_tydesc(*t)];
this.visit("tup_field", extra);
}
})
}
// FIXME (#2594): fetch constants out of intrinsic
// FIXME (#4809): visitor should break out bare fns from other fns
ty::ty_closure(ref fty) => {
let pureval = ast_purity_constant(fty.purity);
let sigilval = ast_sigil_constant(fty.sigil);
let retval = if ty::type_is_bot(fty.sig.output) {0u} else {1u};
let extra = ~[self.c_uint(pureval),
self.c_uint(sigilval),
self.c_uint(fty.sig.inputs.len()),
self.c_uint(retval)];
self.visit("enter_fn", extra);
self.visit_sig(retval, &fty.sig);
self.visit("leave_fn", extra);
}
// FIXME (#2594): fetch constants out of intrinsic:: for the
// numbers.
ty::ty_bare_fn(ref fty) => {
let pureval = ast_purity_constant(fty.purity);
let sigilval = 0u;
let retval = if ty::type_is_bot(fty.sig.output) {0u} else {1u};
let extra = ~[self.c_uint(pureval),
self.c_uint(sigilval),
self.c_uint(fty.sig.inputs.len()),
self.c_uint(retval)];
self.visit("enter_fn", extra);
self.visit_sig(retval, &fty.sig);
self.visit("leave_fn", extra);
}
ty::ty_struct(did, ref substs) => {
let fields = ty::struct_fields(tcx, did, substs);
let mut named_fields = false;
if !fields.is_empty() {
named_fields =
fields[0].ident.name != special_idents::unnamed_field.name;
}
let extra = ~[
self.c_slice(token::intern_and_get_ident(ty_to_str(tcx,
t))),
self.c_bool(named_fields),
self.c_uint(fields.len())
] + self.c_size_and_align(t);
self.bracketed("class", extra, |this| {
for (i, field) in fields.iter().enumerate() {
let extra = ~[
this.c_uint(i),
this.c_slice(token::get_ident(field.ident)),
this.c_bool(named_fields)
] + this.c_mt(&field.mt);
this.visit("class_field", extra);
}
})
}
// FIXME (#2595): visiting all the variants in turn is probably
// not ideal. It'll work but will get costly on big enums. Maybe
// let the visitor tell us if it wants to visit only a particular
// variant?
ty::ty_enum(did, ref substs) => {
let ccx = bcx.ccx();
let repr = adt::represent_type(bcx.ccx(), t);
let variants = ty::substd_enum_variants(ccx.tcx, did, substs);
let llptrty = type_of(ccx, t).ptr_to();
let opaquety = ty::get_opaque_ty(ccx.tcx).unwrap();
let opaqueptrty = ty::mk_ptr(ccx.tcx, ty::mt { ty: opaquety,
mutbl: ast::MutImmutable });
let make_get_disr = || {
let sym = mangle_internal_name_by_path_and_seq(
ast_map::Values([].iter()).chain(None), "get_disr");
let llfdecl = decl_internal_rust_fn(ccx, false, [opaqueptrty], ty::mk_u64(), sym);
let arena = TypedArena::new();
let fcx = new_fn_ctxt(ccx, llfdecl, -1, false,
ty::mk_u64(), None, None, &arena);
init_function(&fcx, false, ty::mk_u64(), None);
let arg = unsafe {
//
// we know the return type of llfdecl is an int here, so
// no need for a special check to see if the return type
// is immediate.
//
llvm::LLVMGetParam(llfdecl, fcx.arg_pos(0u) as c_uint)
};
let bcx = fcx.entry_bcx.get().unwrap();
let arg = BitCast(bcx, arg, llptrty);
let ret = adt::trans_get_discr(bcx, repr, arg, Some(Type::i64()));
Store(bcx, ret, fcx.llretptr.get().unwrap());
match fcx.llreturn.get() {
Some(llreturn) => Br(bcx, llreturn),
None => {}
};
finish_fn(&fcx, bcx);
llfdecl
};
let enum_args = ~[self.c_uint(variants.len()), make_get_disr()]
+ self.c_size_and_align(t);
self.bracketed("enum", enum_args, |this| {
for (i, v) in variants.iter().enumerate() {
let name = token::get_ident(v.name);
let variant_args = ~[this.c_uint(i),
C_u64(v.disr_val),
this.c_uint(v.args.len()),
this.c_slice(name)];
this.bracketed("enum_variant", variant_args, |this| {
for (j, a) in v.args.iter().enumerate() {
let bcx = this.bcx;
let null = C_null(llptrty);
let ptr = adt::trans_field_ptr(bcx, repr, null, v.disr_val, j);
let offset = p2i(ccx, ptr);
let field_args = ~[this.c_uint(j),
offset,
this.c_tydesc(*a)];
this.visit("enum_variant_field", field_args);
}
})
}
})
}
ty::ty_trait(_, _, _, _, _) => {
let extra = [
self.c_slice(token::intern_and_get_ident(ty_to_str(tcx, t)))
];
self.visit("trait", extra);
}
// Miscellaneous extra types
ty::ty_infer(_) => self.leaf("infer"),
ty::ty_err => self.leaf("err"),
ty::ty_param(ref p) => {
let extra = ~[self.c_uint(p.idx)];
self.visit("param", extra)
}
ty::ty_self(..) => self.leaf("self")
}
}
pub fn visit_sig(&mut self, retval: uint, sig: &ty::FnSig) {
for (i, arg) in sig.inputs.iter().enumerate() {
let modeval = 5u; // "by copy"
let extra = ~[self.c_uint(i),
self.c_uint(modeval),
self.c_tydesc(*arg)];
self.visit("fn_input", extra);
}
let extra = ~[self.c_uint(retval),
self.c_bool(sig.variadic),
self.c_tydesc(sig.output)];
self.visit("fn_output", extra);
}
}
// Emit a sequence of calls to visit_ty::visit_foo
pub fn emit_calls_to_trait_visit_ty<'a>(
bcx: &'a Block<'a>,
t: ty::t,
visitor_val: ValueRef,
visitor_trait_id: DefId)
-> &'a Block<'a> {
let fcx = bcx.fcx;
let final = fcx.new_temp_block("final");
let tydesc_ty = ty::get_tydesc_ty(bcx.ccx().tcx).unwrap();
let tydesc_ty = type_of(bcx.ccx(), tydesc_ty);
let mut r = Reflector {
visitor_val: visitor_val,
visitor_methods: ty::trait_methods(bcx.tcx(), visitor_trait_id),
final_bcx: final,
tydesc_ty: tydesc_ty,
bcx: bcx
};
r.visit_ty(t);
Br(r.bcx, final.llbb);
return final;
}
pub fn ast_sigil_constant(sigil: ast::Sigil) -> uint {
match sigil {
ast::OwnedSigil => 2u,
ast::ManagedSigil => 3u,
ast::BorrowedSigil => 4u,
}
}
pub fn ast_purity_constant(purity: ast::Purity) -> uint {
match purity {
ast::UnsafeFn => 1u,
ast::ImpureFn => 2u,
ast::ExternFn => 3u
}
}