Remove a sorting operation from used_crates

This commit is contained in:
bjorn3 2021-06-07 15:23:44 +02:00
parent 9a27044f42
commit 2977dff116
2 changed files with 18 additions and 29 deletions

View file

@ -19,7 +19,7 @@ use rustc_hir::def_id::{DefId, LOCAL_CRATE};
use rustc_hir::lang_items::LangItem;
use rustc_index::vec::Idx;
use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
use rustc_middle::middle::cstore::{self, EncodedMetadata};
use rustc_middle::middle::cstore::EncodedMetadata;
use rustc_middle::middle::lang_items;
use rustc_middle::mir::mono::{CodegenUnit, CodegenUnitNameBuilder, MonoItem};
use rustc_middle::ty::layout::{HasTyCtxt, TyAndLayout};
@ -769,6 +769,22 @@ impl CrateInfo {
subsystem.to_string()
});
// This list is used when generating the command line to pass through to
// system linker. The linker expects undefined symbols on the left of the
// command line to be defined in libraries on the right, not the other way
// around. For more info, see some comments in the add_used_library function
// below.
//
// In order to get this left-to-right dependency ordering, we use the reverse
// postorder of all crates putting the leaves at the right-most positions.
let used_crates = tcx
.postorder_cnums(())
.iter()
.rev()
.copied()
.filter(|&cnum| !tcx.dep_kind(cnum).macros_only())
.collect();
let mut info = CrateInfo {
local_crate_name,
panic_runtime: None,
@ -778,7 +794,7 @@ impl CrateInfo {
native_libraries: Default::default(),
used_libraries: tcx.native_libraries(LOCAL_CRATE).iter().map(Into::into).collect(),
crate_name: Default::default(),
used_crates: cstore::used_crates(tcx),
used_crates,
used_crate_source: Default::default(),
lang_item_to_crate: Default::default(),
missing_lang_items: Default::default(),

View file

@ -197,30 +197,3 @@ pub trait CrateStore {
}
pub type CrateStoreDyn = dyn CrateStore + sync::Sync;
// This method is used when generating the command line to pass through to
// system linker. The linker expects undefined symbols on the left of the
// command line to be defined in libraries on the right, not the other way
// around. For more info, see some comments in the add_used_library function
// below.
//
// In order to get this left-to-right dependency ordering, we perform a
// topological sort of all crates putting the leaves at the right-most
// positions.
pub fn used_crates(tcx: TyCtxt<'_>) -> Vec<CrateNum> {
let mut libs = tcx
.crates(())
.iter()
.cloned()
.filter_map(|cnum| {
if tcx.dep_kind(cnum).macros_only() {
return None;
}
Some(cnum)
})
.collect::<Vec<_>>();
let mut ordering = tcx.postorder_cnums(()).to_owned();
ordering.reverse();
libs.sort_by_cached_key(|&a| ordering.iter().position(|x| *x == a));
libs
}