rust/src/librustc_trans/trans/collector.rs

1598 lines
62 KiB
Rust

// Copyright 2014 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.
//! Translation Item Collection
//! ===========================
//!
//! This module is responsible for discovering all items that will contribute to
//! to code generation of the crate. The important part here is that it not only
//! needs to find syntax-level items (functions, structs, etc) but also all
//! their monomorphized instantiations. Every non-generic, non-const function
//! maps to one LLVM artifact. Every generic function can produce
//! from zero to N artifacts, depending on the sets of type arguments it
//! is instantiated with.
//! This also applies to generic items from other crates: A generic definition
//! in crate X might produce monomorphizations that are compiled into crate Y.
//! We also have to collect these here.
//!
//! The following kinds of "translation items" are handled here:
//!
//! - Functions
//! - Methods
//! - Closures
//! - Statics
//! - Drop glue
//!
//! The following things also result in LLVM artifacts, but are not collected
//! here, since we instantiate them locally on demand when needed in a given
//! codegen unit:
//!
//! - Constants
//! - Vtables
//! - Object Shims
//!
//!
//! General Algorithm
//! -----------------
//! Let's define some terms first:
//!
//! - A "translation item" is something that results in a function or global in
//! the LLVM IR of a codegen unit. Translation items do not stand on their
//! own, they can reference other translation items. For example, if function
//! `foo()` calls function `bar()` then the translation item for `foo()`
//! references the translation item for function `bar()`. In general, the
//! definition for translation item A referencing a translation item B is that
//! the LLVM artifact produced for A references the LLVM artifact produced
//! for B.
//!
//! - Translation items and the references between them for a directed graph,
//! where the translation items are the nodes and references form the edges.
//! Let's call this graph the "translation item graph".
//!
//! - The translation item graph for a program contains all translation items
//! that are needed in order to produce the complete LLVM IR of the program.
//!
//! The purpose of the algorithm implemented in this module is to build the
//! translation item graph for the current crate. It runs in two phases:
//!
//! 1. Discover the roots of the graph by traversing the HIR of the crate.
//! 2. Starting from the roots, find neighboring nodes by inspecting the MIR
//! representation of the item corresponding to a given node, until no more
//! new nodes are found.
//!
//! ### Discovering roots
//!
//! The roots of the translation item graph correspond to the non-generic
//! syntactic items in the source code. We find them by walking the HIR of the
//! crate, and whenever we hit upon a function, method, or static item, we
//! create a translation item consisting of the items DefId and, since we only
//! consider non-generic items, an empty type-substitution set.
//!
//! ### Finding neighbor nodes
//! Given a translation item node, we can discover neighbors by inspecting its
//! MIR. We walk the MIR and any time we hit upon something that signifies a
//! reference to another translation item, we have found a neighbor. Since the
//! translation item we are currently at is always monomorphic, we also know the
//! concrete type arguments of its neighbors, and so all neighbors again will be
//! monomorphic. The specific forms a reference to a neighboring node can take
//! in MIR are quite diverse. Here is an overview:
//!
//! #### Calling Functions/Methods
//! The most obvious form of one translation item referencing another is a
//! function or method call (represented by a CALL terminator in MIR). But
//! calls are not the only thing that might introduce a reference between two
//! function translation items, and as we will see below, they are just a
//! specialized of the form described next, and consequently will don't get any
//! special treatment in the algorithm.
//!
//! #### Taking a reference to a function or method
//! A function does not need to actually be called in order to be a neighbor of
//! another function. It suffices to just take a reference in order to introduce
//! an edge. Consider the following example:
//!
//! ```rust
//! fn print_val<T: Display>(x: T) {
//! println!("{}", x);
//! }
//!
//! fn call_fn(f: &Fn(i32), x: i32) {
//! f(x);
//! }
//!
//! fn main() {
//! let print_i32 = print_val::<i32>;
//! call_fn(&print_i32, 0);
//! }
//! ```
//! The MIR of none of these functions will contain an explicit call to
//! `print_val::<i32>`. Nonetheless, in order to translate this program, we need
//! an instance of this function. Thus, whenever we encounter a function or
//! method in operand position, we treat it as a neighbor of the current
//! translation item. Calls are just a special case of that.
//!
//! #### Closures
//! In a way, closures are a simple case. Since every closure object needs to be
//! constructed somewhere, we can reliably discover them by observing
//! `RValue::Aggregate` expressions with `AggregateKind::Closure`. This is also
//! true for closures inlined from other crates.
//!
//! #### Drop glue
//! Drop glue translation items are introduced by MIR drop-statements. The
//! generated translation item will again have drop-glue item neighbors if the
//! type to be dropped contains nested values that also need to be dropped. It
//! might also have a function item neighbor for the explicit `Drop::drop`
//! implementation of its type.
//!
//! #### Unsizing Casts
//! A subtle way of introducing neighbor edges is by casting to a trait object.
//! Since the resulting fat-pointer contains a reference to a vtable, we need to
//! instantiate all object-save methods of the trait, as we need to store
//! pointers to these functions even if they never get called anywhere. This can
//! be seen as a special case of taking a function reference.
//!
//! #### Boxes
//! Since `Box` expression have special compiler support, no explicit calls to
//! `exchange_malloc()` and `exchange_free()` may show up in MIR, even if the
//! compiler will generate them. We have to observe `Rvalue::Box` expressions
//! and Box-typed drop-statements for that purpose.
//!
//!
//! Interaction with Cross-Crate Inlining
//! -------------------------------------
//! The binary of a crate will not only contain machine code for the items
//! defined in the source code of that crate. It will also contain monomorphic
//! instantiations of any extern generic functions and of functions marked with
//! #[inline].
//! The collection algorithm handles this more or less transparently. If it is
//! about to create a translation item for something with an external `DefId`,
//! it will take a look if the MIR for that item is available, and if so just
//! proceed normally. If the MIR is not available, it assumes that that item is
//! just linked to and no node is created; which is exactly what we want, since
//! no machine code should be generated in the current crate for such an item.
//!
//! Eager and Lazy Collection Mode
//! ------------------------------
//! Translation item collection can be performed in one of two modes:
//!
//! - Lazy mode means that items will only be instantiated when actually
//! referenced. The goal is to produce the least amount of machine code
//! possible.
//!
//! - Eager mode is meant to be used in conjunction with incremental compilation
//! where a stable set of translation items is more important than a minimal
//! one. Thus, eager mode will instantiate drop-glue for every drop-able type
//! in the crate, even of no drop call for that type exists (yet). It will
//! also instantiate default implementations of trait methods, something that
//! otherwise is only done on demand.
//!
//!
//! Open Issues
//! -----------
//! Some things are not yet fully implemented in the current version of this
//! module.
//!
//! ### Initializers of Constants and Statics
//! Since no MIR is constructed yet for initializer expressions of constants and
//! statics we cannot inspect these properly.
//!
//! ### Const Fns
//! Ideally, no translation item should be generated for const fns unless there
//! is a call to them that cannot be evaluated at compile time. At the moment
//! this is not implemented however: a translation item will be produced
//! regardless of whether it is actually needed or not.
use rustc_front::hir;
use rustc_front::intravisit as hir_visit;
use rustc::front::map as hir_map;
use rustc::middle::def_id::DefId;
use rustc::middle::lang_items::{ExchangeFreeFnLangItem, ExchangeMallocFnLangItem};
use rustc::middle::{ty, traits};
use rustc::middle::subst::{self, Substs, Subst};
use rustc::middle::ty::adjustment::CustomCoerceUnsized;
use rustc::middle::ty::fold::TypeFoldable;
use rustc::mir::repr as mir;
use rustc::mir::visit as mir_visit;
use rustc::mir::visit::Visitor as MirVisitor;
use syntax::ast::{self, NodeId};
use syntax::codemap::DUMMY_SP;
use syntax::errors;
use syntax::parse::token;
use trans::base::custom_coerce_unsize_info;
use trans::context::CrateContext;
use trans::common::{fulfill_obligation, normalize_and_test_predicates,
type_is_sized};
use trans::glue;
use trans::meth;
use trans::monomorphize;
use util::nodemap::{FnvHashSet, FnvHashMap, DefIdMap};
use std::hash::{Hash, Hasher};
use std::rc::Rc;
#[derive(PartialEq, Eq, Hash, Clone, Copy, Debug)]
pub enum TransItemCollectionMode {
Eager,
Lazy
}
#[derive(Eq, Clone, Copy, Debug)]
pub enum TransItem<'tcx> {
DropGlue(ty::Ty<'tcx>),
Fn {
def_id: DefId,
substs: &'tcx Substs<'tcx>
},
Static(NodeId)
}
impl<'tcx> Hash for TransItem<'tcx> {
fn hash<H: Hasher>(&self, s: &mut H) {
match *self {
TransItem::DropGlue(t) => {
0u8.hash(s);
t.hash(s);
},
TransItem::Fn { def_id, substs } => {
1u8.hash(s);
def_id.hash(s);
(substs as *const Substs<'tcx> as usize).hash(s);
}
TransItem::Static(node_id) => {
3u8.hash(s);
node_id.hash(s);
}
};
}
}
impl<'tcx> PartialEq for TransItem<'tcx> {
fn eq(&self, other: &Self) -> bool {
match (*self, *other) {
(TransItem::DropGlue(t1), TransItem::DropGlue(t2)) => t1 == t2,
(TransItem::Fn { def_id: def_id1, substs: substs1 },
TransItem::Fn { def_id: def_id2, substs: substs2 }) => {
def_id1 == def_id2 && substs1 == substs2
},
(TransItem::Static(node_id1), TransItem::Static(node_id2)) => {
node_id1 == node_id2
},
_ => false
}
}
}
pub fn collect_crate_translation_items<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
mode: TransItemCollectionMode)
-> FnvHashSet<TransItem<'tcx>> {
// We are not tracking dependencies of this pass as it has to be re-executed
// every time no matter what.
ccx.tcx().dep_graph.with_ignore(|| {
let roots = collect_roots(ccx, mode);
debug!("Building translation item graph, beginning at roots");
let mut visited = FnvHashSet();
let mut recursion_depths = DefIdMap();
let mut mir_cache = DefIdMap();
for root in roots {
collect_items_rec(ccx,
root,
&mut visited,
&mut recursion_depths,
&mut mir_cache);
}
visited
})
}
// Find all non-generic items by walking the HIR. These items serve as roots to
// start monomorphizing from.
fn collect_roots<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
mode: TransItemCollectionMode)
-> Vec<TransItem<'tcx>> {
debug!("Collecting roots");
let mut roots = Vec::new();
{
let mut visitor = RootCollector {
ccx: ccx,
mode: mode,
output: &mut roots,
enclosing_item: None,
trans_empty_substs: ccx.tcx().mk_substs(Substs::trans_empty()),
};
ccx.tcx().map.krate().visit_all_items(&mut visitor);
}
roots
}
#[derive(Clone)]
enum CachedMir<'mir, 'tcx: 'mir> {
Ref(&'mir mir::Mir<'tcx>),
Owned(Rc<mir::Mir<'tcx>>)
}
impl<'mir, 'tcx: 'mir> CachedMir<'mir, 'tcx> {
fn get_ref<'a>(&'a self) -> &'a mir::Mir<'tcx> {
match *self {
CachedMir::Ref(r) => r,
CachedMir::Owned(ref rc) => &**rc,
}
}
}
// Collect all monomorphized translation items reachable from `starting_point`
fn collect_items_rec<'a, 'tcx: 'a>(ccx: &CrateContext<'a, 'tcx>,
starting_point: TransItem<'tcx>,
visited: &mut FnvHashSet<TransItem<'tcx>>,
recursion_depths: &mut DefIdMap<usize>,
mir_cache: &mut DefIdMap<CachedMir<'a, 'tcx>>) {
if !visited.insert(starting_point.clone()) {
// We've been here already, no need to search again.
return;
}
debug!("BEGIN collect_items_rec({})", starting_point.to_string(ccx));
let mut neighbors = Vec::new();
let recursion_depth_reset;
match starting_point {
TransItem::DropGlue(t) => {
find_drop_glue_neighbors(ccx, t, &mut neighbors);
recursion_depth_reset = None;
}
TransItem::Static(_) => {
recursion_depth_reset = None;
}
TransItem::Fn { def_id, substs: ref param_substs } => {
// Keep track of the monomorphization recursion depth
recursion_depth_reset = Some(check_recursion_limit(ccx,
def_id,
recursion_depths));
// Scan the MIR in order to find function calls, closures, and
// drop-glue
let mir = load_mir(ccx, def_id, mir_cache);
let mut visitor = MirNeighborCollector {
ccx: ccx,
mir: mir.get_ref(),
output: &mut neighbors,
param_substs: param_substs
};
visitor.visit_mir(mir.get_ref());
}
}
for neighbour in neighbors {
collect_items_rec(ccx, neighbour, visited, recursion_depths, mir_cache);
}
if let Some((def_id, depth)) = recursion_depth_reset {
recursion_depths.insert(def_id, depth);
}
debug!("END collect_items_rec({})", starting_point.to_string(ccx));
}
fn load_mir<'a, 'tcx: 'a>(ccx: &CrateContext<'a, 'tcx>,
def_id: DefId,
mir_cache: &mut DefIdMap<CachedMir<'a, 'tcx>>)
-> CachedMir<'a, 'tcx> {
let mir_not_found_error_message = || {
format!("Could not find MIR for function: {}",
ccx.tcx().item_path_str(def_id))
};
if def_id.is_local() {
let node_id = ccx.tcx().map.as_local_node_id(def_id).unwrap();
let mir_opt = ccx.mir_map().map.get(&node_id);
let mir = errors::expect(ccx.sess().diagnostic(),
mir_opt,
mir_not_found_error_message);
CachedMir::Ref(mir)
} else {
if let Some(mir) = mir_cache.get(&def_id) {
return mir.clone();
}
let mir_opt = ccx.sess().cstore.maybe_get_item_mir(ccx.tcx(), def_id);
let mir = errors::expect(ccx.sess().diagnostic(),
mir_opt,
mir_not_found_error_message);
let cached = CachedMir::Owned(Rc::new(mir));
mir_cache.insert(def_id, cached.clone());
cached
}
}
fn check_recursion_limit<'a, 'tcx: 'a>(ccx: &CrateContext<'a, 'tcx>,
def_id: DefId,
recursion_depths: &mut DefIdMap<usize>)
-> (DefId, usize) {
let recursion_depth = recursion_depths.get(&def_id)
.map(|x| *x)
.unwrap_or(0);
debug!(" => recursion depth={}", recursion_depth);
// Code that needs to instantiate the same function recursively
// more than the recursion limit is assumed to be causing an
// infinite expansion.
if recursion_depth > ccx.sess().recursion_limit.get() {
if let Some(node_id) = ccx.tcx().map.as_local_node_id(def_id) {
ccx.sess().span_fatal(ccx.tcx().map.span(node_id),
"reached the recursion limit during monomorphization");
} else {
let error = format!("reached the recursion limit during \
monomorphization of '{}'",
ccx.tcx().item_path_str(def_id));
ccx.sess().fatal(&error[..]);
}
}
recursion_depths.insert(def_id, recursion_depth + 1);
(def_id, recursion_depth)
}
struct MirNeighborCollector<'a, 'tcx: 'a> {
ccx: &'a CrateContext<'a, 'tcx>,
mir: &'a mir::Mir<'tcx>,
output: &'a mut Vec<TransItem<'tcx>>,
param_substs: &'tcx Substs<'tcx>
}
impl<'a, 'tcx> MirVisitor<'tcx> for MirNeighborCollector<'a, 'tcx> {
fn visit_rvalue(&mut self, rvalue: &mir::Rvalue<'tcx>) {
debug!("visiting rvalue {:?}", *rvalue);
match *rvalue {
mir::Rvalue::Aggregate(mir::AggregateKind::Closure(def_id,
ref substs), _) => {
assert!(can_have_local_instance(self.ccx, def_id));
let trans_item = create_fn_trans_item(self.ccx,
def_id,
substs.func_substs,
self.param_substs);
self.output.push(trans_item);
}
// When doing an cast from a regular pointer to a fat pointer, we
// have to instantiate all methods of the trait being cast to, so we
// can build the appropriate vtable.
mir::Rvalue::Cast(mir::CastKind::Unsize, ref operand, target_ty) => {
let target_ty = monomorphize::apply_param_substs(self.ccx.tcx(),
self.param_substs,
&target_ty);
let source_ty = self.mir.operand_ty(self.ccx.tcx(), operand);
let source_ty = monomorphize::apply_param_substs(self.ccx.tcx(),
self.param_substs,
&source_ty);
let (source_ty, target_ty) = find_vtable_types_for_unsizing(self.ccx,
source_ty,
target_ty);
// This could also be a different Unsize instruction, like
// from a fixed sized array to a slice. But we are only
// interested in things that produce a vtable.
if target_ty.is_trait() && !source_ty.is_trait() {
create_trans_items_for_vtable_methods(self.ccx,
target_ty,
source_ty,
self.output);
}
}
mir::Rvalue::Box(_) => {
let exchange_malloc_fn_def_id =
self.ccx
.tcx()
.lang_items
.require(ExchangeMallocFnLangItem)
.expect("Could not find ExchangeMallocFnLangItem");
assert!(can_have_local_instance(self.ccx, exchange_malloc_fn_def_id));
let exchange_malloc_fn_trans_item =
create_fn_trans_item(self.ccx,
exchange_malloc_fn_def_id,
&Substs::trans_empty(),
self.param_substs);
self.output.push(exchange_malloc_fn_trans_item);
}
_ => { /* not interesting */ }
}
self.super_rvalue(rvalue);
}
fn visit_lvalue(&mut self,
lvalue: &mir::Lvalue<'tcx>,
context: mir_visit::LvalueContext) {
debug!("visiting lvalue {:?}", *lvalue);
if let mir_visit::LvalueContext::Drop = context {
let ty = self.mir.lvalue_ty(self.ccx.tcx(), lvalue)
.to_ty(self.ccx.tcx());
let ty = monomorphize::apply_param_substs(self.ccx.tcx(),
self.param_substs,
&ty);
let ty = self.ccx.tcx().erase_regions(&ty);
let ty = glue::get_drop_glue_type(self.ccx, ty);
self.output.push(TransItem::DropGlue(ty));
}
self.super_lvalue(lvalue, context);
}
fn visit_operand(&mut self, operand: &mir::Operand<'tcx>) {
debug!("visiting operand {:?}", *operand);
let callee = match *operand {
mir::Operand::Constant(mir::Constant {
literal: mir::Literal::Item {
def_id,
kind,
substs
},
..
}) if is_function_or_method(kind) => Some((def_id, substs)),
_ => None
};
if let Some((callee_def_id, callee_substs)) = callee {
debug!(" => operand is callable");
// `callee_def_id` might refer to a trait method instead of a
// concrete implementation, so we have to find the actual
// implementation. For example, the call might look like
//
// std::cmp::partial_cmp(0i32, 1i32)
//
// Calling do_static_dispatch() here will map the def_id of
// `std::cmp::partial_cmp` to the def_id of `i32::partial_cmp<i32>`
let dispatched = do_static_dispatch(self.ccx,
callee_def_id,
callee_substs,
self.param_substs);
if let Some((callee_def_id, callee_substs)) = dispatched {
// if we have a concrete impl (which we might not have
// in the case of something compiler generated like an
// object shim or a closure that is handled differently),
// we check if the callee is something that will actually
// result in a translation item ...
if can_result_in_trans_item(self.ccx, callee_def_id) {
// ... and create one if it does.
let trans_item = create_fn_trans_item(self.ccx,
callee_def_id,
callee_substs,
self.param_substs);
self.output.push(trans_item);
}
}
}
self.super_operand(operand);
fn is_function_or_method(item_kind: mir::ItemKind) -> bool {
match item_kind {
mir::ItemKind::Constant => false,
mir::ItemKind::Function |
mir::ItemKind::Method => true
}
}
fn can_result_in_trans_item<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
def_id: DefId)
-> bool {
if !match ccx.tcx().lookup_item_type(def_id).ty.sty {
ty::TyBareFn(Some(def_id), _) => {
// Some constructors also have type TyBareFn but they are
// always instantiated inline and don't result in
// translation item.
match ccx.tcx().map.get_if_local(def_id) {
Some(hir_map::NodeVariant(_)) |
Some(hir_map::NodeStructCtor(_)) => false,
Some(_) => true,
None => {
ccx.sess().cstore.variant_kind(def_id).is_none()
}
}
}
ty::TyClosure(..) => true,
_ => false
} {
return false;
}
can_have_local_instance(ccx, def_id)
}
}
}
fn can_have_local_instance<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
def_id: DefId)
-> bool {
// Take a look if we have the definition available. If not, we
// will not emit code for this item in the local crate, and thus
// don't create a translation item for it.
def_id.is_local() || ccx.sess().cstore.is_item_mir_available(def_id)
}
fn find_drop_glue_neighbors<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
ty: ty::Ty<'tcx>,
output: &mut Vec<TransItem<'tcx>>)
{
debug!("find_drop_glue_neighbors: {}", type_to_string(ccx, ty));
// Make sure the exchange_free_fn() lang-item gets translated if
// there is a boxed value.
if let ty::TyBox(_) = ty.sty {
let exchange_free_fn_def_id = ccx.tcx()
.lang_items
.require(ExchangeFreeFnLangItem)
.expect("Could not find ExchangeFreeFnLangItem");
assert!(can_have_local_instance(ccx, exchange_free_fn_def_id));
let exchange_free_fn_trans_item =
create_fn_trans_item(ccx,
exchange_free_fn_def_id,
&Substs::trans_empty(),
&Substs::trans_empty());
output.push(exchange_free_fn_trans_item);
}
// If the type implements Drop, also add a translation item for the
// monomorphized Drop::drop() implementation.
let destructor_did = match ty.sty {
ty::TyStruct(def, _) |
ty::TyEnum(def, _) => def.destructor(),
_ => None
};
if let Some(destructor_did) = destructor_did {
use rustc::middle::ty::ToPolyTraitRef;
let drop_trait_def_id = ccx.tcx()
.lang_items
.drop_trait()
.unwrap();
let self_type_substs = ccx.tcx().mk_substs(
Substs::trans_empty().with_self_ty(ty));
let trait_ref = ty::TraitRef {
def_id: drop_trait_def_id,
substs: self_type_substs,
}.to_poly_trait_ref();
let substs = match fulfill_obligation(ccx, DUMMY_SP, trait_ref) {
traits::VtableImpl(data) => data.substs,
_ => unreachable!()
};
if can_have_local_instance(ccx, destructor_did) {
let trans_item = create_fn_trans_item(ccx,
destructor_did,
ccx.tcx().mk_substs(substs),
&Substs::trans_empty());
output.push(trans_item);
}
}
// Finally add the types of nested values
match ty.sty {
ty::TyBool |
ty::TyChar |
ty::TyInt(_) |
ty::TyUint(_) |
ty::TyStr |
ty::TyFloat(_) |
ty::TyRawPtr(_) |
ty::TyRef(..) |
ty::TyBareFn(..) |
ty::TySlice(_) |
ty::TyTrait(_) => {
/* nothing to do */
}
ty::TyStruct(ref adt_def, substs) |
ty::TyEnum(ref adt_def, substs) => {
for field in adt_def.all_fields() {
let field_type = monomorphize::apply_param_substs(ccx.tcx(),
substs,
&field.unsubst_ty());
let field_type = glue::get_drop_glue_type(ccx, field_type);
if glue::type_needs_drop(ccx.tcx(), field_type) {
output.push(TransItem::DropGlue(field_type));
}
}
}
ty::TyClosure(_, ref substs) => {
for upvar_ty in &substs.upvar_tys {
let upvar_ty = glue::get_drop_glue_type(ccx, upvar_ty);
if glue::type_needs_drop(ccx.tcx(), upvar_ty) {
output.push(TransItem::DropGlue(upvar_ty));
}
}
}
ty::TyBox(inner_type) |
ty::TyArray(inner_type, _) => {
let inner_type = glue::get_drop_glue_type(ccx, inner_type);
if glue::type_needs_drop(ccx.tcx(), inner_type) {
output.push(TransItem::DropGlue(inner_type));
}
}
ty::TyTuple(ref args) => {
for arg in args {
let arg = glue::get_drop_glue_type(ccx, arg);
if glue::type_needs_drop(ccx.tcx(), arg) {
output.push(TransItem::DropGlue(arg));
}
}
}
ty::TyProjection(_) |
ty::TyParam(_) |
ty::TyInfer(_) |
ty::TyError => {
ccx.sess().bug("encountered unexpected type");
}
}
}
fn do_static_dispatch<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
fn_def_id: DefId,
fn_substs: &'tcx Substs<'tcx>,
param_substs: &'tcx Substs<'tcx>)
-> Option<(DefId, &'tcx Substs<'tcx>)> {
debug!("do_static_dispatch(fn_def_id={}, fn_substs={:?}, param_substs={:?})",
def_id_to_string(ccx, fn_def_id, None),
fn_substs,
param_substs);
let is_trait_method = ccx.tcx().trait_of_item(fn_def_id).is_some();
if is_trait_method {
match ccx.tcx().impl_or_trait_item(fn_def_id) {
ty::MethodTraitItem(ref method) => {
match method.container {
ty::TraitContainer(trait_def_id) => {
debug!(" => trait method, attempting to find impl");
do_static_trait_method_dispatch(ccx,
method,
trait_def_id,
fn_substs,
param_substs)
}
ty::ImplContainer(_) => {
// This is already a concrete implementation
debug!(" => impl method");
Some((fn_def_id, fn_substs))
}
}
}
_ => unreachable!()
}
} else {
debug!(" => regular function");
// The function is not part of an impl or trait, no dispatching
// to be done
Some((fn_def_id, fn_substs))
}
}
// Given a trait-method and substitution information, find out the actual
// implementation of the trait method.
fn do_static_trait_method_dispatch<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
trait_method: &ty::Method,
trait_id: DefId,
callee_substs: &'tcx Substs<'tcx>,
param_substs: &'tcx Substs<'tcx>)
-> Option<(DefId, &'tcx Substs<'tcx>)> {
let tcx = ccx.tcx();
debug!("do_static_trait_method_dispatch(trait_method={}, \
trait_id={}, \
callee_substs={:?}, \
param_substs={:?}",
def_id_to_string(ccx, trait_method.def_id, None),
def_id_to_string(ccx, trait_id, None),
callee_substs,
param_substs);
let rcvr_substs = monomorphize::apply_param_substs(tcx,
param_substs,
callee_substs);
let trait_ref = ty::Binder(rcvr_substs.to_trait_ref(tcx, trait_id));
let vtbl = fulfill_obligation(ccx, DUMMY_SP, trait_ref);
// Now that we know which impl is being used, we can dispatch to
// the actual function:
match vtbl {
traits::VtableImpl(traits::VtableImplData {
impl_def_id: impl_did,
substs: impl_substs,
nested: _ }) =>
{
let callee_substs = impl_substs.with_method_from(&rcvr_substs);
let impl_method = tcx.get_impl_method(impl_did,
callee_substs,
trait_method.name);
Some((impl_method.method.def_id, tcx.mk_substs(impl_method.substs)))
}
// If we have a closure or a function pointer, we will also encounter
// the concrete closure/function somewhere else (during closure or fn
// pointer construction). That's where we track those things.
traits::VtableClosure(..) |
traits::VtableFnPointer(..) |
traits::VtableObject(..) => {
None
}
_ => {
tcx.sess.bug(&format!("static call to invalid vtable: {:?}", vtbl))
}
}
}
/// For given pair of source and target type that occur in an unsizing coercion,
/// this function finds the pair of types that determines the vtable linking
/// them.
///
/// For example, the source type might be `&SomeStruct` and the target type\
/// might be `&SomeTrait` in a cast like:
///
/// let src: &SomeStruct = ...;
/// let target = src as &SomeTrait;
///
/// Then the output of this function would be (SomeStruct, SomeTrait) since for
/// constructing the `target` fat-pointer we need the vtable for that pair.
///
/// Things can get more complicated though because there's also the case where
/// the unsized type occurs as a field:
///
/// ```rust
/// struct ComplexStruct<T: ?Sized> {
/// a: u32,
/// b: f64,
/// c: T
/// }
/// ```
///
/// In this case, if `T` is sized, `&ComplexStruct<T>` is a thin pointer. If `T`
/// is unsized, `&SomeStruct` is a fat pointer, and the vtable it points to is
/// for the pair of `T` (which is a trait) and the concrete type that `T` was
/// originally coerced from:
///
/// let src: &ComplexStruct<SomeStruct> = ...;
/// let target = src as &ComplexStruct<SomeTrait>;
///
/// Again, we want this `find_vtable_types_for_unsizing()` to provide the pair
/// `(SomeStruct, SomeTrait)`.
///
/// Finally, there is also the case of custom unsizing coercions, e.g. for
/// smart pointers such as `Rc` and `Arc`.
fn find_vtable_types_for_unsizing<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
source_ty: ty::Ty<'tcx>,
target_ty: ty::Ty<'tcx>)
-> (ty::Ty<'tcx>, ty::Ty<'tcx>) {
match (&source_ty.sty, &target_ty.sty) {
(&ty::TyBox(a), &ty::TyBox(b)) |
(&ty::TyRef(_, ty::TypeAndMut { ty: a, .. }),
&ty::TyRef(_, ty::TypeAndMut { ty: b, .. })) |
(&ty::TyRef(_, ty::TypeAndMut { ty: a, .. }),
&ty::TyRawPtr(ty::TypeAndMut { ty: b, .. })) |
(&ty::TyRawPtr(ty::TypeAndMut { ty: a, .. }),
&ty::TyRawPtr(ty::TypeAndMut { ty: b, .. })) => {
let (inner_source, inner_target) = (a, b);
if !type_is_sized(ccx.tcx(), inner_source) {
(inner_source, inner_target)
} else {
ccx.tcx().struct_lockstep_tails(inner_source, inner_target)
}
}
(&ty::TyStruct(source_adt_def, source_substs),
&ty::TyStruct(target_adt_def, target_substs)) => {
assert_eq!(source_adt_def, target_adt_def);
let kind = custom_coerce_unsize_info(ccx, source_ty, target_ty);
let coerce_index = match kind {
CustomCoerceUnsized::Struct(i) => i
};
let source_fields = &source_adt_def.struct_variant().fields;
let target_fields = &target_adt_def.struct_variant().fields;
assert!(coerce_index < source_fields.len() &&
source_fields.len() == target_fields.len());
find_vtable_types_for_unsizing(ccx,
source_fields[coerce_index].ty(ccx.tcx(),
source_substs),
target_fields[coerce_index].ty(ccx.tcx(),
target_substs))
}
_ => ccx.sess()
.bug(&format!("find_vtable_types_for_unsizing: invalid coercion {:?} -> {:?}",
source_ty,
target_ty))
}
}
fn create_fn_trans_item<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
def_id: DefId,
fn_substs: &Substs<'tcx>,
param_substs: &Substs<'tcx>)
-> TransItem<'tcx>
{
debug!("create_fn_trans_item(def_id={}, fn_substs={:?}, param_substs={:?})",
def_id_to_string(ccx, def_id, None),
fn_substs,
param_substs);
// We only get here, if fn_def_id either designates a local item or
// an inlineable external item. Non-inlineable external items are
// ignored because we don't want to generate any code for them.
let concrete_substs = monomorphize::apply_param_substs(ccx.tcx(),
param_substs,
fn_substs);
let concrete_substs = ccx.tcx().erase_regions(&concrete_substs);
let trans_item = TransItem::Fn {
def_id: def_id,
substs: ccx.tcx().mk_substs(concrete_substs),
};
return trans_item;
}
/// Creates a `TransItem` for each method that is referenced by the vtable for
/// the given trait/impl pair.
fn create_trans_items_for_vtable_methods<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
trait_ty: ty::Ty<'tcx>,
impl_ty: ty::Ty<'tcx>,
output: &mut Vec<TransItem<'tcx>>) {
assert!(!trait_ty.needs_subst() && !impl_ty.needs_subst());
if let ty::TyTrait(ref trait_ty) = trait_ty.sty {
let poly_trait_ref = trait_ty.principal_trait_ref_with_self_ty(ccx.tcx(),
impl_ty);
// Walk all methods of the trait, including those of its supertraits
for trait_ref in traits::supertraits(ccx.tcx(), poly_trait_ref) {
let vtable = fulfill_obligation(ccx, DUMMY_SP, trait_ref);
match vtable {
traits::VtableImpl(
traits::VtableImplData {
impl_def_id,
substs,
nested: _ }) => {
let items = meth::get_vtable_methods(ccx, impl_def_id, substs)
.into_iter()
// filter out None values
.filter_map(|opt_impl_method| opt_impl_method)
// create translation items
.filter_map(|impl_method| {
if can_have_local_instance(ccx, impl_method.method.def_id) {
let substs = ccx.tcx().mk_substs(impl_method.substs);
Some(create_fn_trans_item(ccx,
impl_method.method.def_id,
substs,
&Substs::trans_empty()))
} else {
None
}
})
.collect::<Vec<_>>();
output.extend(items.into_iter());
}
_ => { /* */ }
}
}
}
}
//=-----------------------------------------------------------------------------
// Root Collection
//=-----------------------------------------------------------------------------
struct RootCollector<'b, 'a: 'b, 'tcx: 'a + 'b> {
ccx: &'b CrateContext<'a, 'tcx>,
mode: TransItemCollectionMode,
output: &'b mut Vec<TransItem<'tcx>>,
enclosing_item: Option<&'tcx hir::Item>,
trans_empty_substs: &'tcx Substs<'tcx>
}
impl<'b, 'a, 'v> hir_visit::Visitor<'v> for RootCollector<'b, 'a, 'v> {
fn visit_item(&mut self, item: &'v hir::Item) {
let old_enclosing_item = self.enclosing_item;
self.enclosing_item = Some(item);
match item.node {
hir::ItemExternCrate(..) |
hir::ItemUse(..) |
hir::ItemForeignMod(..) |
hir::ItemTy(..) |
hir::ItemDefaultImpl(..) |
hir::ItemTrait(..) |
hir::ItemConst(..) |
hir::ItemMod(..) => {
// Nothing to do, just keep recursing...
}
hir::ItemImpl(..) => {
if self.mode == TransItemCollectionMode::Eager {
create_trans_items_for_default_impls(self.ccx,
item,
self.trans_empty_substs,
self.output);
}
}
hir::ItemEnum(_, ref generics) |
hir::ItemStruct(_, ref generics) => {
if !generics.is_parameterized() {
let ty = {
let tables = self.ccx.tcx().tables.borrow();
tables.node_types[&item.id]
};
if self.mode == TransItemCollectionMode::Eager {
debug!("RootCollector: ADT drop-glue for {}",
def_id_to_string(self.ccx,
self.ccx.tcx().map.local_def_id(item.id),
None));
let ty = glue::get_drop_glue_type(self.ccx, ty);
self.output.push(TransItem::DropGlue(ty));
}
}
}
hir::ItemStatic(..) => {
debug!("RootCollector: ItemStatic({})",
def_id_to_string(self.ccx,
self.ccx.tcx().map.local_def_id(item.id),
None));
self.output.push(TransItem::Static(item.id));
}
hir::ItemFn(_, _, constness, _, ref generics, _) => {
if !generics.is_type_parameterized() &&
constness == hir::Constness::NotConst {
let def_id = self.ccx.tcx().map.local_def_id(item.id);
debug!("RootCollector: ItemFn({})",
def_id_to_string(self.ccx, def_id, None));
self.output.push(TransItem::Fn {
def_id: def_id,
substs: self.trans_empty_substs
});
}
}
}
hir_visit::walk_item(self, item);
self.enclosing_item = old_enclosing_item;
}
fn visit_impl_item(&mut self, ii: &'v hir::ImplItem) {
match ii.node {
hir::ImplItemKind::Method(hir::MethodSig {
ref generics,
constness,
..
}, _) if constness == hir::Constness::NotConst => {
let hir_map = &self.ccx.tcx().map;
let parent_node_id = hir_map.get_parent_node(ii.id);
let is_impl_generic = match hir_map.expect_item(parent_node_id) {
&hir::Item {
node: hir::ItemImpl(_, _, ref generics, _, _, _),
..
} => {
generics.is_type_parameterized()
}
_ => {
unreachable!()
}
};
if !generics.is_type_parameterized() && !is_impl_generic {
let def_id = self.ccx.tcx().map.local_def_id(ii.id);
debug!("RootCollector: MethodImplItem({})",
def_id_to_string(self.ccx, def_id, None));
self.output.push(TransItem::Fn {
def_id: def_id,
substs: self.trans_empty_substs
});
}
}
_ => { /* Nothing to do here */ }
}
hir_visit::walk_impl_item(self, ii)
}
}
fn create_trans_items_for_default_impls<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
item: &'tcx hir::Item,
trans_empty_substs: &'tcx Substs<'tcx>,
output: &mut Vec<TransItem<'tcx>>) {
match item.node {
hir::ItemImpl(_,
_,
ref generics,
_,
_,
ref items) => {
if generics.is_type_parameterized() {
return
}
let tcx = ccx.tcx();
let impl_def_id = tcx.map.local_def_id(item.id);
debug!("create_trans_items_for_default_impls(item={})",
def_id_to_string(ccx, impl_def_id, None));
if let Some(trait_ref) = tcx.impl_trait_ref(impl_def_id) {
let default_impls = tcx.provided_trait_methods(trait_ref.def_id);
let callee_substs = tcx.mk_substs(tcx.erase_regions(trait_ref.substs));
let overridden_methods: FnvHashSet<_> = items.iter()
.map(|item| item.name)
.collect();
for default_impl in default_impls {
if overridden_methods.contains(&default_impl.name) {
continue;
}
if default_impl.generics.has_type_params(subst::FnSpace) {
continue;
}
// The substitutions we have are on the impl, so we grab
// the method type from the impl to substitute into.
let mth = tcx.get_impl_method(impl_def_id,
callee_substs.clone(),
default_impl.name);
assert!(mth.is_provided);
let predicates = mth.method.predicates.predicates.subst(tcx, &mth.substs);
if !normalize_and_test_predicates(ccx, predicates.into_vec()) {
continue;
}
if can_have_local_instance(ccx, default_impl.def_id) {
let item = create_fn_trans_item(ccx,
default_impl.def_id,
callee_substs,
trans_empty_substs);
output.push(item);
}
}
}
}
_ => {
unreachable!()
}
}
}
//=-----------------------------------------------------------------------------
// TransItem String Keys
//=-----------------------------------------------------------------------------
// The code below allows for producing a unique string key for a trans item.
// These keys are used by the handwritten auto-tests, so they need to be
// predictable and human-readable.
//
// Note: A lot of this could looks very similar to what's already in the
// ppaux module. It would be good to refactor things so we only have one
// parameterizable implementation for printing types.
/// Same as `unique_type_name()` but with the result pushed onto the given
/// `output` parameter.
pub fn push_unique_type_name<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
t: ty::Ty<'tcx>,
output: &mut String) {
match t.sty {
ty::TyBool => output.push_str("bool"),
ty::TyChar => output.push_str("char"),
ty::TyStr => output.push_str("str"),
ty::TyInt(ast::TyIs) => output.push_str("isize"),
ty::TyInt(ast::TyI8) => output.push_str("i8"),
ty::TyInt(ast::TyI16) => output.push_str("i16"),
ty::TyInt(ast::TyI32) => output.push_str("i32"),
ty::TyInt(ast::TyI64) => output.push_str("i64"),
ty::TyUint(ast::TyUs) => output.push_str("usize"),
ty::TyUint(ast::TyU8) => output.push_str("u8"),
ty::TyUint(ast::TyU16) => output.push_str("u16"),
ty::TyUint(ast::TyU32) => output.push_str("u32"),
ty::TyUint(ast::TyU64) => output.push_str("u64"),
ty::TyFloat(ast::TyF32) => output.push_str("f32"),
ty::TyFloat(ast::TyF64) => output.push_str("f64"),
ty::TyStruct(adt_def, substs) |
ty::TyEnum(adt_def, substs) => {
push_item_name(cx, adt_def.did, output);
push_type_params(cx, substs, &[], output);
},
ty::TyTuple(ref component_types) => {
output.push('(');
for &component_type in component_types {
push_unique_type_name(cx, component_type, output);
output.push_str(", ");
}
if !component_types.is_empty() {
output.pop();
output.pop();
}
output.push(')');
},
ty::TyBox(inner_type) => {
output.push_str("Box<");
push_unique_type_name(cx, inner_type, output);
output.push('>');
},
ty::TyRawPtr(ty::TypeAndMut { ty: inner_type, mutbl } ) => {
output.push('*');
match mutbl {
hir::MutImmutable => output.push_str("const "),
hir::MutMutable => output.push_str("mut "),
}
push_unique_type_name(cx, inner_type, output);
},
ty::TyRef(_, ty::TypeAndMut { ty: inner_type, mutbl }) => {
output.push('&');
if mutbl == hir::MutMutable {
output.push_str("mut ");
}
push_unique_type_name(cx, inner_type, output);
},
ty::TyArray(inner_type, len) => {
output.push('[');
push_unique_type_name(cx, inner_type, output);
output.push_str(&format!("; {}", len));
output.push(']');
},
ty::TySlice(inner_type) => {
output.push('[');
push_unique_type_name(cx, inner_type, output);
output.push(']');
},
ty::TyTrait(ref trait_data) => {
push_item_name(cx, trait_data.principal.skip_binder().def_id, output);
push_type_params(cx,
&trait_data.principal.skip_binder().substs,
&trait_data.bounds.projection_bounds,
output);
},
ty::TyBareFn(_, &ty::BareFnTy{ unsafety, abi, ref sig } ) => {
if unsafety == hir::Unsafety::Unsafe {
output.push_str("unsafe ");
}
if abi != ::syntax::abi::Rust {
output.push_str("extern \"");
output.push_str(abi.name());
output.push_str("\" ");
}
output.push_str("fn(");
let sig = cx.tcx().erase_late_bound_regions(sig);
if !sig.inputs.is_empty() {
for &parameter_type in &sig.inputs {
push_unique_type_name(cx, parameter_type, output);
output.push_str(", ");
}
output.pop();
output.pop();
}
if sig.variadic {
if !sig.inputs.is_empty() {
output.push_str(", ...");
} else {
output.push_str("...");
}
}
output.push(')');
match sig.output {
ty::FnConverging(result_type) if result_type.is_nil() => {}
ty::FnConverging(result_type) => {
output.push_str(" -> ");
push_unique_type_name(cx, result_type, output);
}
ty::FnDiverging => {
output.push_str(" -> !");
}
}
},
ty::TyClosure(def_id, ref closure_substs) => {
push_item_name(cx, def_id, output);
output.push_str("{");
output.push_str(&format!("{}:{}", def_id.krate, def_id.index.as_usize()));
output.push_str("}");
push_type_params(cx, closure_substs.func_substs, &[], output);
}
ty::TyError |
ty::TyInfer(_) |
ty::TyProjection(..) |
ty::TyParam(_) => {
cx.sess().bug(&format!("debuginfo: Trying to create type name for \
unexpected type: {:?}", t));
}
}
}
fn push_item_name(ccx: &CrateContext,
def_id: DefId,
output: &mut String) {
if def_id.is_local() {
let node_id = ccx.tcx().map.as_local_node_id(def_id).unwrap();
let inlined_from = ccx.external_srcs()
.borrow()
.get(&node_id)
.map(|def_id| *def_id);
if let Some(extern_def_id) = inlined_from {
push_item_name(ccx, extern_def_id, output);
return;
}
output.push_str(&ccx.link_meta().crate_name);
output.push_str("::");
}
for part in ccx.tcx().def_path(def_id) {
output.push_str(&format!("{}[{}]::",
part.data.as_interned_str(),
part.disambiguator));
}
output.pop();
output.pop();
}
fn push_type_params<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
substs: &Substs<'tcx>,
projections: &[ty::PolyProjectionPredicate<'tcx>],
output: &mut String) {
if substs.types.is_empty() && projections.is_empty() {
return;
}
output.push('<');
for &type_parameter in &substs.types {
push_unique_type_name(cx, type_parameter, output);
output.push_str(", ");
}
for projection in projections {
let projection = projection.skip_binder();
let name = token::get_ident_interner().get(projection.projection_ty.item_name);
output.push_str(&name[..]);
output.push_str("=");
push_unique_type_name(cx, projection.ty, output);
output.push_str(", ");
}
output.pop();
output.pop();
output.push('>');
}
fn push_def_id_as_string<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
def_id: DefId,
substs: Option<&Substs<'tcx>>,
output: &mut String) {
push_item_name(ccx, def_id, output);
if let Some(substs) = substs {
push_type_params(ccx, substs, &[], output);
}
}
fn def_id_to_string<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
def_id: DefId,
substs: Option<&Substs<'tcx>>)
-> String {
let mut output = String::new();
push_def_id_as_string(ccx, def_id, substs, &mut output);
output
}
fn type_to_string<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
ty: ty::Ty<'tcx>)
-> String {
let mut output = String::new();
push_unique_type_name(ccx, ty, &mut output);
output
}
impl<'tcx> TransItem<'tcx> {
pub fn to_string<'a>(&self, ccx: &CrateContext<'a, 'tcx>) -> String {
let hir_map = &ccx.tcx().map;
return match *self {
TransItem::DropGlue(t) => {
let mut s = String::with_capacity(32);
s.push_str("drop-glue ");
push_unique_type_name(ccx, t, &mut s);
s
}
TransItem::Fn { def_id, ref substs } => {
to_string_internal(ccx, "fn ", def_id, Some(substs))
},
TransItem::Static(node_id) => {
let def_id = hir_map.local_def_id(node_id);
to_string_internal(ccx, "static ", def_id, None)
},
};
fn to_string_internal<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
prefix: &str,
def_id: DefId,
substs: Option<&Substs<'tcx>>)
-> String {
let mut result = String::with_capacity(32);
result.push_str(prefix);
push_def_id_as_string(ccx, def_id, substs, &mut result);
result
}
}
fn to_raw_string(&self) -> String {
match *self {
TransItem::DropGlue(t) => {
format!("DropGlue({})", t as *const _ as usize)
}
TransItem::Fn { def_id, substs } => {
format!("Fn({:?}, {})",
def_id,
substs as *const _ as usize)
}
TransItem::Static(id) => {
format!("Static({:?})", id)
}
}
}
}
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
pub enum TransItemState {
PredictedAndGenerated,
PredictedButNotGenerated,
NotPredictedButGenerated,
}
pub fn collecting_debug_information(ccx: &CrateContext) -> bool {
return cfg!(debug_assertions) &&
ccx.sess().opts.debugging_opts.print_trans_items.is_some();
}
pub fn print_collection_results<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>) {
use std::hash::{Hash, SipHasher, Hasher};
if !collecting_debug_information(ccx) {
return;
}
fn hash<T: Hash>(t: &T) -> u64 {
let mut s = SipHasher::new();
t.hash(&mut s);
s.finish()
}
let trans_items = ccx.translation_items().borrow();
{
// Check for duplicate item keys
let mut item_keys = FnvHashMap();
for (item, item_state) in trans_items.iter() {
let k = item.to_string(&ccx);
if item_keys.contains_key(&k) {
let prev: (TransItem, TransItemState) = item_keys[&k];
debug!("DUPLICATE KEY: {}", k);
debug!(" (1) {:?}, {:?}, hash: {}, raw: {}",
prev.0,
prev.1,
hash(&prev.0),
prev.0.to_raw_string());
debug!(" (2) {:?}, {:?}, hash: {}, raw: {}",
*item,
*item_state,
hash(item),
item.to_raw_string());
} else {
item_keys.insert(k, (*item, *item_state));
}
}
}
let mut predicted_but_not_generated = FnvHashSet();
let mut not_predicted_but_generated = FnvHashSet();
let mut predicted = FnvHashSet();
let mut generated = FnvHashSet();
for (item, item_state) in trans_items.iter() {
let item_key = item.to_string(&ccx);
match *item_state {
TransItemState::PredictedAndGenerated => {
predicted.insert(item_key.clone());
generated.insert(item_key);
}
TransItemState::PredictedButNotGenerated => {
predicted_but_not_generated.insert(item_key.clone());
predicted.insert(item_key);
}
TransItemState::NotPredictedButGenerated => {
not_predicted_but_generated.insert(item_key.clone());
generated.insert(item_key);
}
}
}
debug!("Total number of translation items predicted: {}", predicted.len());
debug!("Total number of translation items generated: {}", generated.len());
debug!("Total number of translation items predicted but not generated: {}",
predicted_but_not_generated.len());
debug!("Total number of translation items not predicted but generated: {}",
not_predicted_but_generated.len());
if generated.len() > 0 {
debug!("Failed to predict {}% of translation items",
(100 * not_predicted_but_generated.len()) / generated.len());
}
if generated.len() > 0 {
debug!("Predict {}% too many translation items",
(100 * predicted_but_not_generated.len()) / generated.len());
}
debug!("");
debug!("Not predicted but generated:");
debug!("============================");
for item in not_predicted_but_generated {
debug!(" - {}", item);
}
debug!("");
debug!("Predicted but not generated:");
debug!("============================");
for item in predicted_but_not_generated {
debug!(" - {}", item);
}
}