bjoernager/rust
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Don't export of __rust_* alloc symbols if not codegened

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This commit is contained in:
Collin Baker 2023-02-13 18:48:06 -05:00
parent 9bb87eb681
commit cb41803899
3 changed files with 37 additions and 40 deletions
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44
compiler/rustc_codegen_ssa/src/base.rs
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@ -13,6 +13,7 @@ use crate::mir::place::PlaceRef;
use crate::traits::*;
use crate::{CachedModuleCodegen, CompiledModule, CrateInfo, MemFlags, ModuleCodegen, ModuleKind};
use rustc_ast::expand::allocator::AllocatorKind;
use rustc_attr as attr;
use rustc_data_structures::fx::{FxHashMap, FxHashSet};
use rustc_data_structures::profiling::{get_resident_set_size, print_time_passes_entry};
@ -545,6 +546,23 @@ pub fn collect_debugger_visualizers_transitive(
.collect::<BTreeSet<_>>()
}
/// Decide allocator kind to codegen. If `Some(_)` this will be the same as
/// `tcx.allocator_kind`, but it may be `None` in more cases (e.g. if using
/// allocator definitions from a dylib dependency).
pub fn allocator_kind_for_codegen(tcx: TyCtxt<'_>) -> Option<AllocatorKind> {
// If the crate doesn't have an `allocator_kind` set then there's definitely
// no shim to generate. Otherwise we also check our dependency graph for all
// our output crate types. If anything there looks like its a `Dynamic`
// linkage, then it's already got an allocator shim and we'll be using that
// one instead. If nothing exists then it's our job to generate the
// allocator!
let any_dynamic_crate = tcx.dependency_formats(()).iter().any(|(_, list)| {
use rustc_middle::middle::dependency_format::Linkage;
list.iter().any(|&linkage| linkage == Linkage::Dynamic)
});
if any_dynamic_crate { None } else { tcx.allocator_kind(()) }
}
pub fn codegen_crate<B: ExtraBackendMethods>(
backend: B,
tcx: TyCtxt<'_>,
@ -615,20 +633,7 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
);
// Codegen an allocator shim, if necessary.
//
// If the crate doesn't have an `allocator_kind` set then there's definitely
// no shim to generate. Otherwise we also check our dependency graph for all
// our output crate types. If anything there looks like its a `Dynamic`
// linkage, then it's already got an allocator shim and we'll be using that
// one instead. If nothing exists then it's our job to generate the
// allocator!
let any_dynamic_crate = tcx.dependency_formats(()).iter().any(|(_, list)| {
use rustc_middle::middle::dependency_format::Linkage;
list.iter().any(|&linkage| linkage == Linkage::Dynamic)
});
let allocator_module = if any_dynamic_crate {
None
} else if let Some(kind) = tcx.allocator_kind(()) {
if let Some(kind) = allocator_kind_for_codegen(tcx) {
let llmod_id =
cgu_name_builder.build_cgu_name(LOCAL_CRATE, &["crate"], Some("allocator")).to_string();
let module_llvm = tcx.sess.time("write_allocator_module", || {
@ -642,13 +647,10 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
)
});
Some(ModuleCodegen { name: llmod_id, module_llvm, kind: ModuleKind::Allocator })
} else {
None
};
if let Some(allocator_module) = allocator_module {
ongoing_codegen.submit_pre_codegened_module_to_llvm(tcx, allocator_module);
ongoing_codegen.submit_pre_codegened_module_to_llvm(
tcx,
ModuleCodegen { name: llmod_id, module_llvm, kind: ModuleKind::Allocator },
);
}
// For better throughput during parallel processing by LLVM, we used to sort