1056 lines
42 KiB
Rust
1056 lines
42 KiB
Rust
use crate::assert_module_sources::CguReuse;
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use crate::back::link::are_upstream_rust_objects_already_included;
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use crate::back::metadata::create_compressed_metadata_file;
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use crate::back::write::{
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compute_per_cgu_lto_type, start_async_codegen, submit_codegened_module_to_llvm,
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submit_post_lto_module_to_llvm, submit_pre_lto_module_to_llvm, ComputedLtoType, OngoingCodegen,
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};
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use crate::common::{self, IntPredicate, RealPredicate, TypeKind};
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use crate::errors;
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use crate::meth;
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use crate::mir;
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use crate::mir::operand::OperandValue;
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use crate::mir::place::PlaceRef;
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use crate::traits::*;
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use crate::{CachedModuleCodegen, CompiledModule, CrateInfo, ModuleCodegen, ModuleKind};
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use rustc_ast::expand::allocator::{global_fn_name, AllocatorKind, ALLOCATOR_METHODS};
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use rustc_attr as attr;
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use rustc_data_structures::fx::{FxHashMap, FxIndexSet};
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use rustc_data_structures::profiling::{get_resident_set_size, print_time_passes_entry};
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use rustc_data_structures::sync::par_map;
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use rustc_data_structures::unord::UnordMap;
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use rustc_hir::def_id::{DefId, LOCAL_CRATE};
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use rustc_hir::lang_items::LangItem;
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use rustc_metadata::EncodedMetadata;
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use rustc_middle::bug;
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use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
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use rustc_middle::middle::debugger_visualizer::{DebuggerVisualizerFile, DebuggerVisualizerType};
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use rustc_middle::middle::exported_symbols;
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use rustc_middle::middle::exported_symbols::SymbolExportKind;
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use rustc_middle::middle::lang_items;
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use rustc_middle::mir::mono::{CodegenUnit, CodegenUnitNameBuilder, MonoItem};
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use rustc_middle::mir::BinOp;
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use rustc_middle::query::Providers;
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use rustc_middle::ty::layout::{HasTyCtxt, LayoutOf, TyAndLayout};
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use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
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use rustc_session::config::{self, CrateType, EntryFnType, OptLevel, OutputType};
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use rustc_session::Session;
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use rustc_span::symbol::sym;
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use rustc_span::{Symbol, DUMMY_SP};
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use rustc_target::abi::FIRST_VARIANT;
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use std::cmp;
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use std::collections::BTreeSet;
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use std::time::{Duration, Instant};
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use itertools::Itertools;
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use tracing::{debug, info};
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pub fn bin_op_to_icmp_predicate(op: BinOp, signed: bool) -> IntPredicate {
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match op {
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BinOp::Eq => IntPredicate::IntEQ,
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BinOp::Ne => IntPredicate::IntNE,
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BinOp::Lt => {
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if signed {
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IntPredicate::IntSLT
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} else {
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IntPredicate::IntULT
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}
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}
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BinOp::Le => {
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if signed {
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IntPredicate::IntSLE
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} else {
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IntPredicate::IntULE
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}
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}
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BinOp::Gt => {
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if signed {
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IntPredicate::IntSGT
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} else {
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IntPredicate::IntUGT
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}
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}
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BinOp::Ge => {
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if signed {
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IntPredicate::IntSGE
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} else {
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IntPredicate::IntUGE
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}
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}
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op => bug!(
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"comparison_op_to_icmp_predicate: expected comparison operator, \
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found {:?}",
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op
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),
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}
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}
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pub fn bin_op_to_fcmp_predicate(op: BinOp) -> RealPredicate {
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match op {
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BinOp::Eq => RealPredicate::RealOEQ,
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BinOp::Ne => RealPredicate::RealUNE,
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BinOp::Lt => RealPredicate::RealOLT,
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BinOp::Le => RealPredicate::RealOLE,
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BinOp::Gt => RealPredicate::RealOGT,
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BinOp::Ge => RealPredicate::RealOGE,
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op => {
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bug!(
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"comparison_op_to_fcmp_predicate: expected comparison operator, \
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found {:?}",
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op
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);
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}
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}
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}
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pub fn compare_simd_types<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
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bx: &mut Bx,
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lhs: Bx::Value,
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rhs: Bx::Value,
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t: Ty<'tcx>,
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ret_ty: Bx::Type,
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op: BinOp,
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) -> Bx::Value {
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let signed = match t.kind() {
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ty::Float(_) => {
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let cmp = bin_op_to_fcmp_predicate(op);
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let cmp = bx.fcmp(cmp, lhs, rhs);
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return bx.sext(cmp, ret_ty);
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}
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ty::Uint(_) => false,
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ty::Int(_) => true,
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_ => bug!("compare_simd_types: invalid SIMD type"),
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};
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let cmp = bin_op_to_icmp_predicate(op, signed);
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let cmp = bx.icmp(cmp, lhs, rhs);
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// LLVM outputs an `< size x i1 >`, so we need to perform a sign extension
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// to get the correctly sized type. This will compile to a single instruction
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// once the IR is converted to assembly if the SIMD instruction is supported
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// by the target architecture.
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bx.sext(cmp, ret_ty)
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}
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/// Retrieves the information we are losing (making dynamic) in an unsizing
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/// adjustment.
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///
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/// The `old_info` argument is a bit odd. It is intended for use in an upcast,
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/// where the new vtable for an object will be derived from the old one.
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pub fn unsized_info<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
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bx: &mut Bx,
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source: Ty<'tcx>,
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target: Ty<'tcx>,
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old_info: Option<Bx::Value>,
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) -> Bx::Value {
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let cx = bx.cx();
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let (source, target) =
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cx.tcx().struct_lockstep_tails_erasing_lifetimes(source, target, bx.param_env());
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match (source.kind(), target.kind()) {
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(&ty::Array(_, len), &ty::Slice(_)) => {
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cx.const_usize(len.eval_target_usize(cx.tcx(), ty::ParamEnv::reveal_all()))
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}
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(&ty::Dynamic(data_a, _, src_dyn_kind), &ty::Dynamic(data_b, _, target_dyn_kind))
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if src_dyn_kind == target_dyn_kind =>
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{
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let old_info =
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old_info.expect("unsized_info: missing old info for trait upcasting coercion");
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if data_a.principal_def_id() == data_b.principal_def_id() {
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// A NOP cast that doesn't actually change anything, should be allowed even with invalid vtables.
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return old_info;
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}
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// trait upcasting coercion
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let vptr_entry_idx = cx.tcx().supertrait_vtable_slot((source, target));
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if let Some(entry_idx) = vptr_entry_idx {
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let ptr_size = bx.data_layout().pointer_size;
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let ptr_align = bx.data_layout().pointer_align.abi;
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let vtable_byte_offset = u64::try_from(entry_idx).unwrap() * ptr_size.bytes();
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let gep = bx.inbounds_ptradd(old_info, bx.const_usize(vtable_byte_offset));
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let new_vptr = bx.load(bx.type_ptr(), gep, ptr_align);
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bx.nonnull_metadata(new_vptr);
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// VTable loads are invariant.
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bx.set_invariant_load(new_vptr);
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new_vptr
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} else {
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old_info
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}
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}
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(_, ty::Dynamic(data, _, _)) => meth::get_vtable(cx, source, data.principal()),
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_ => bug!("unsized_info: invalid unsizing {:?} -> {:?}", source, target),
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}
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}
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/// Coerces `src` to `dst_ty`. `src_ty` must be a pointer.
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pub fn unsize_ptr<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
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bx: &mut Bx,
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src: Bx::Value,
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src_ty: Ty<'tcx>,
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dst_ty: Ty<'tcx>,
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old_info: Option<Bx::Value>,
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) -> (Bx::Value, Bx::Value) {
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debug!("unsize_ptr: {:?} => {:?}", src_ty, dst_ty);
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match (src_ty.kind(), dst_ty.kind()) {
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(&ty::Ref(_, a, _), &ty::Ref(_, b, _) | &ty::RawPtr(b, _))
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| (&ty::RawPtr(a, _), &ty::RawPtr(b, _)) => {
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assert_eq!(bx.cx().type_is_sized(a), old_info.is_none());
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(src, unsized_info(bx, a, b, old_info))
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}
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(&ty::Adt(def_a, _), &ty::Adt(def_b, _)) => {
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assert_eq!(def_a, def_b); // implies same number of fields
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let src_layout = bx.cx().layout_of(src_ty);
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let dst_layout = bx.cx().layout_of(dst_ty);
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if src_ty == dst_ty {
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return (src, old_info.unwrap());
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}
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let mut result = None;
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for i in 0..src_layout.fields.count() {
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let src_f = src_layout.field(bx.cx(), i);
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if src_f.is_1zst() {
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// We are looking for the one non-1-ZST field; this is not it.
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continue;
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}
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assert_eq!(src_layout.fields.offset(i).bytes(), 0);
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assert_eq!(dst_layout.fields.offset(i).bytes(), 0);
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assert_eq!(src_layout.size, src_f.size);
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let dst_f = dst_layout.field(bx.cx(), i);
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assert_ne!(src_f.ty, dst_f.ty);
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assert_eq!(result, None);
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result = Some(unsize_ptr(bx, src, src_f.ty, dst_f.ty, old_info));
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}
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result.unwrap()
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}
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_ => bug!("unsize_ptr: called on bad types"),
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}
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}
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/// Coerces `src` to `dst_ty` which is guaranteed to be a `dyn*` type.
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pub fn cast_to_dyn_star<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
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bx: &mut Bx,
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src: Bx::Value,
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src_ty_and_layout: TyAndLayout<'tcx>,
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dst_ty: Ty<'tcx>,
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old_info: Option<Bx::Value>,
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) -> (Bx::Value, Bx::Value) {
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debug!("cast_to_dyn_star: {:?} => {:?}", src_ty_and_layout.ty, dst_ty);
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assert!(
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matches!(dst_ty.kind(), ty::Dynamic(_, _, ty::DynStar)),
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||
"destination type must be a dyn*"
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||
);
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||
let src = match bx.cx().type_kind(bx.cx().backend_type(src_ty_and_layout)) {
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||
TypeKind::Pointer => src,
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TypeKind::Integer => bx.inttoptr(src, bx.type_ptr()),
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||
// FIXME(dyn-star): We probably have to do a bitcast first, then inttoptr.
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kind => bug!("unexpected TypeKind for left-hand side of `dyn*` cast: {kind:?}"),
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||
};
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(src, unsized_info(bx, src_ty_and_layout.ty, dst_ty, old_info))
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||
}
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||
|
||
/// Coerces `src`, which is a reference to a value of type `src_ty`,
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||
/// to a value of type `dst_ty`, and stores the result in `dst`.
|
||
pub fn coerce_unsized_into<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
|
||
bx: &mut Bx,
|
||
src: PlaceRef<'tcx, Bx::Value>,
|
||
dst: PlaceRef<'tcx, Bx::Value>,
|
||
) {
|
||
let src_ty = src.layout.ty;
|
||
let dst_ty = dst.layout.ty;
|
||
match (src_ty.kind(), dst_ty.kind()) {
|
||
(&ty::Ref(..), &ty::Ref(..) | &ty::RawPtr(..)) | (&ty::RawPtr(..), &ty::RawPtr(..)) => {
|
||
let (base, info) = match bx.load_operand(src).val {
|
||
OperandValue::Pair(base, info) => unsize_ptr(bx, base, src_ty, dst_ty, Some(info)),
|
||
OperandValue::Immediate(base) => unsize_ptr(bx, base, src_ty, dst_ty, None),
|
||
OperandValue::Ref(..) | OperandValue::ZeroSized => bug!(),
|
||
};
|
||
OperandValue::Pair(base, info).store(bx, dst);
|
||
}
|
||
|
||
(&ty::Adt(def_a, _), &ty::Adt(def_b, _)) => {
|
||
assert_eq!(def_a, def_b); // implies same number of fields
|
||
|
||
for i in def_a.variant(FIRST_VARIANT).fields.indices() {
|
||
let src_f = src.project_field(bx, i.as_usize());
|
||
let dst_f = dst.project_field(bx, i.as_usize());
|
||
|
||
if dst_f.layout.is_zst() {
|
||
// No data here, nothing to copy/coerce.
|
||
continue;
|
||
}
|
||
|
||
if src_f.layout.ty == dst_f.layout.ty {
|
||
bx.typed_place_copy(dst_f.val, src_f.val, src_f.layout);
|
||
} else {
|
||
coerce_unsized_into(bx, src_f, dst_f);
|
||
}
|
||
}
|
||
}
|
||
_ => bug!("coerce_unsized_into: invalid coercion {:?} -> {:?}", src_ty, dst_ty,),
|
||
}
|
||
}
|
||
|
||
/// Returns `rhs` sufficiently masked, truncated, and/or extended so that it can be used to shift
|
||
/// `lhs`: it has the same size as `lhs`, and the value, when interpreted unsigned (no matter its
|
||
/// type), will not exceed the size of `lhs`.
|
||
///
|
||
/// Shifts in MIR are all allowed to have mismatched LHS & RHS types, and signed RHS.
|
||
/// The shift methods in `BuilderMethods`, however, are fully homogeneous
|
||
/// (both parameters and the return type are all the same size) and assume an unsigned RHS.
|
||
///
|
||
/// If `is_unchecked` is false, this masks the RHS to ensure it stays in-bounds,
|
||
/// as the `BuilderMethods` shifts are UB for out-of-bounds shift amounts.
|
||
/// For 32- and 64-bit types, this matches the semantics
|
||
/// of Java. (See related discussion on #1877 and #10183.)
|
||
///
|
||
/// If `is_unchecked` is true, this does no masking, and adds sufficient `assume`
|
||
/// calls or operation flags to preserve as much freedom to optimize as possible.
|
||
pub fn build_shift_expr_rhs<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
|
||
bx: &mut Bx,
|
||
lhs: Bx::Value,
|
||
mut rhs: Bx::Value,
|
||
is_unchecked: bool,
|
||
) -> Bx::Value {
|
||
// Shifts may have any size int on the rhs
|
||
let mut rhs_llty = bx.cx().val_ty(rhs);
|
||
let mut lhs_llty = bx.cx().val_ty(lhs);
|
||
|
||
let mask = common::shift_mask_val(bx, lhs_llty, rhs_llty, false);
|
||
if !is_unchecked {
|
||
rhs = bx.and(rhs, mask);
|
||
}
|
||
|
||
if bx.cx().type_kind(rhs_llty) == TypeKind::Vector {
|
||
rhs_llty = bx.cx().element_type(rhs_llty)
|
||
}
|
||
if bx.cx().type_kind(lhs_llty) == TypeKind::Vector {
|
||
lhs_llty = bx.cx().element_type(lhs_llty)
|
||
}
|
||
let rhs_sz = bx.cx().int_width(rhs_llty);
|
||
let lhs_sz = bx.cx().int_width(lhs_llty);
|
||
if lhs_sz < rhs_sz {
|
||
if is_unchecked && bx.sess().opts.optimize != OptLevel::No {
|
||
// FIXME: Use `trunc nuw` once that's available
|
||
let inrange = bx.icmp(IntPredicate::IntULE, rhs, mask);
|
||
bx.assume(inrange);
|
||
}
|
||
|
||
bx.trunc(rhs, lhs_llty)
|
||
} else if lhs_sz > rhs_sz {
|
||
// We zero-extend even if the RHS is signed. So e.g. `(x: i32) << -1i8` will zero-extend the
|
||
// RHS to `255i32`. But then we mask the shift amount to be within the size of the LHS
|
||
// anyway so the result is `31` as it should be. All the extra bits introduced by zext
|
||
// are masked off so their value does not matter.
|
||
// FIXME: if we ever support 512bit integers, this will be wrong! For such large integers,
|
||
// the extra bits introduced by zext are *not* all masked away any more.
|
||
assert!(lhs_sz <= 256);
|
||
bx.zext(rhs, lhs_llty)
|
||
} else {
|
||
rhs
|
||
}
|
||
}
|
||
|
||
// Returns `true` if this session's target will use native wasm
|
||
// exceptions. This means that the VM does the unwinding for
|
||
// us
|
||
pub fn wants_wasm_eh(sess: &Session) -> bool {
|
||
sess.target.is_like_wasm && sess.target.os != "emscripten"
|
||
}
|
||
|
||
/// Returns `true` if this session's target will use SEH-based unwinding.
|
||
///
|
||
/// This is only true for MSVC targets, and even then the 64-bit MSVC target
|
||
/// currently uses SEH-ish unwinding with DWARF info tables to the side (same as
|
||
/// 64-bit MinGW) instead of "full SEH".
|
||
pub fn wants_msvc_seh(sess: &Session) -> bool {
|
||
sess.target.is_like_msvc
|
||
}
|
||
|
||
/// Returns `true` if this session's target requires the new exception
|
||
/// handling LLVM IR instructions (catchpad / cleanuppad / ... instead
|
||
/// of landingpad)
|
||
pub fn wants_new_eh_instructions(sess: &Session) -> bool {
|
||
wants_wasm_eh(sess) || wants_msvc_seh(sess)
|
||
}
|
||
|
||
pub fn codegen_instance<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
|
||
cx: &'a Bx::CodegenCx,
|
||
instance: Instance<'tcx>,
|
||
) {
|
||
// this is an info! to allow collecting monomorphization statistics
|
||
// and to allow finding the last function before LLVM aborts from
|
||
// release builds.
|
||
info!("codegen_instance({})", instance);
|
||
|
||
mir::codegen_mir::<Bx>(cx, instance);
|
||
}
|
||
|
||
/// Creates the `main` function which will initialize the rust runtime and call
|
||
/// users main function.
|
||
pub fn maybe_create_entry_wrapper<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
|
||
cx: &'a Bx::CodegenCx,
|
||
) -> Option<Bx::Function> {
|
||
let (main_def_id, entry_type) = cx.tcx().entry_fn(())?;
|
||
let main_is_local = main_def_id.is_local();
|
||
let instance = Instance::mono(cx.tcx(), main_def_id);
|
||
|
||
if main_is_local {
|
||
// We want to create the wrapper in the same codegen unit as Rust's main
|
||
// function.
|
||
if !cx.codegen_unit().contains_item(&MonoItem::Fn(instance)) {
|
||
return None;
|
||
}
|
||
} else if !cx.codegen_unit().is_primary() {
|
||
// We want to create the wrapper only when the codegen unit is the primary one
|
||
return None;
|
||
}
|
||
|
||
let main_llfn = cx.get_fn_addr(instance);
|
||
|
||
let entry_fn = create_entry_fn::<Bx>(cx, main_llfn, main_def_id, entry_type);
|
||
return Some(entry_fn);
|
||
|
||
fn create_entry_fn<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
|
||
cx: &'a Bx::CodegenCx,
|
||
rust_main: Bx::Value,
|
||
rust_main_def_id: DefId,
|
||
entry_type: EntryFnType,
|
||
) -> Bx::Function {
|
||
// The entry function is either `int main(void)` or `int main(int argc, char **argv)`, or
|
||
// `usize efi_main(void *handle, void *system_table)` depending on the target.
|
||
let llfty = if cx.sess().target.os.contains("uefi") {
|
||
cx.type_func(&[cx.type_ptr(), cx.type_ptr()], cx.type_isize())
|
||
} else if cx.sess().target.main_needs_argc_argv {
|
||
cx.type_func(&[cx.type_int(), cx.type_ptr()], cx.type_int())
|
||
} else {
|
||
cx.type_func(&[], cx.type_int())
|
||
};
|
||
|
||
let main_ret_ty = cx.tcx().fn_sig(rust_main_def_id).no_bound_vars().unwrap().output();
|
||
// Given that `main()` has no arguments,
|
||
// then its return type cannot have
|
||
// late-bound regions, since late-bound
|
||
// regions must appear in the argument
|
||
// listing.
|
||
let main_ret_ty = cx.tcx().normalize_erasing_regions(
|
||
ty::ParamEnv::reveal_all(),
|
||
main_ret_ty.no_bound_vars().unwrap(),
|
||
);
|
||
|
||
let Some(llfn) = cx.declare_c_main(llfty) else {
|
||
// FIXME: We should be smart and show a better diagnostic here.
|
||
let span = cx.tcx().def_span(rust_main_def_id);
|
||
cx.tcx().dcx().emit_fatal(errors::MultipleMainFunctions { span });
|
||
};
|
||
|
||
// `main` should respect same config for frame pointer elimination as rest of code
|
||
cx.set_frame_pointer_type(llfn);
|
||
cx.apply_target_cpu_attr(llfn);
|
||
|
||
let llbb = Bx::append_block(cx, llfn, "top");
|
||
let mut bx = Bx::build(cx, llbb);
|
||
|
||
bx.insert_reference_to_gdb_debug_scripts_section_global();
|
||
|
||
let isize_ty = cx.type_isize();
|
||
let ptr_ty = cx.type_ptr();
|
||
let (arg_argc, arg_argv) = get_argc_argv(cx, &mut bx);
|
||
|
||
let (start_fn, start_ty, args, instance) = if let EntryFnType::Main { sigpipe } = entry_type
|
||
{
|
||
let start_def_id = cx.tcx().require_lang_item(LangItem::Start, None);
|
||
let start_instance = ty::Instance::expect_resolve(
|
||
cx.tcx(),
|
||
ty::ParamEnv::reveal_all(),
|
||
start_def_id,
|
||
cx.tcx().mk_args(&[main_ret_ty.into()]),
|
||
DUMMY_SP,
|
||
);
|
||
let start_fn = cx.get_fn_addr(start_instance);
|
||
|
||
let i8_ty = cx.type_i8();
|
||
let arg_sigpipe = bx.const_u8(sigpipe);
|
||
|
||
let start_ty = cx.type_func(&[cx.val_ty(rust_main), isize_ty, ptr_ty, i8_ty], isize_ty);
|
||
(
|
||
start_fn,
|
||
start_ty,
|
||
vec![rust_main, arg_argc, arg_argv, arg_sigpipe],
|
||
Some(start_instance),
|
||
)
|
||
} else {
|
||
debug!("using user-defined start fn");
|
||
let start_ty = cx.type_func(&[isize_ty, ptr_ty], isize_ty);
|
||
(rust_main, start_ty, vec![arg_argc, arg_argv], None)
|
||
};
|
||
|
||
let result = bx.call(start_ty, None, None, start_fn, &args, None, instance);
|
||
if cx.sess().target.os.contains("uefi") {
|
||
bx.ret(result);
|
||
} else {
|
||
let cast = bx.intcast(result, cx.type_int(), true);
|
||
bx.ret(cast);
|
||
}
|
||
|
||
llfn
|
||
}
|
||
}
|
||
|
||
/// Obtain the `argc` and `argv` values to pass to the rust start function.
|
||
fn get_argc_argv<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
|
||
cx: &'a Bx::CodegenCx,
|
||
bx: &mut Bx,
|
||
) -> (Bx::Value, Bx::Value) {
|
||
if cx.sess().target.os.contains("uefi") {
|
||
// Params for UEFI
|
||
let param_handle = bx.get_param(0);
|
||
let param_system_table = bx.get_param(1);
|
||
let ptr_size = bx.tcx().data_layout.pointer_size;
|
||
let ptr_align = bx.tcx().data_layout.pointer_align.abi;
|
||
let arg_argc = bx.const_int(cx.type_isize(), 2);
|
||
let arg_argv = bx.alloca(2 * ptr_size, ptr_align);
|
||
bx.store(param_handle, arg_argv, ptr_align);
|
||
let arg_argv_el1 = bx.inbounds_ptradd(arg_argv, bx.const_usize(ptr_size.bytes()));
|
||
bx.store(param_system_table, arg_argv_el1, ptr_align);
|
||
(arg_argc, arg_argv)
|
||
} else if cx.sess().target.main_needs_argc_argv {
|
||
// Params from native `main()` used as args for rust start function
|
||
let param_argc = bx.get_param(0);
|
||
let param_argv = bx.get_param(1);
|
||
let arg_argc = bx.intcast(param_argc, cx.type_isize(), true);
|
||
let arg_argv = param_argv;
|
||
(arg_argc, arg_argv)
|
||
} else {
|
||
// The Rust start function doesn't need `argc` and `argv`, so just pass zeros.
|
||
let arg_argc = bx.const_int(cx.type_int(), 0);
|
||
let arg_argv = bx.const_null(cx.type_ptr());
|
||
(arg_argc, arg_argv)
|
||
}
|
||
}
|
||
|
||
/// This function returns all of the debugger visualizers specified for the
|
||
/// current crate as well as all upstream crates transitively that match the
|
||
/// `visualizer_type` specified.
|
||
pub fn collect_debugger_visualizers_transitive(
|
||
tcx: TyCtxt<'_>,
|
||
visualizer_type: DebuggerVisualizerType,
|
||
) -> BTreeSet<DebuggerVisualizerFile> {
|
||
tcx.debugger_visualizers(LOCAL_CRATE)
|
||
.iter()
|
||
.chain(
|
||
tcx.crates(())
|
||
.iter()
|
||
.filter(|&cnum| {
|
||
let used_crate_source = tcx.used_crate_source(*cnum);
|
||
used_crate_source.rlib.is_some() || used_crate_source.rmeta.is_some()
|
||
})
|
||
.flat_map(|&cnum| tcx.debugger_visualizers(cnum)),
|
||
)
|
||
.filter(|visualizer| visualizer.visualizer_type == visualizer_type)
|
||
.cloned()
|
||
.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<'_>,
|
||
target_cpu: String,
|
||
metadata: EncodedMetadata,
|
||
need_metadata_module: bool,
|
||
) -> OngoingCodegen<B> {
|
||
// Skip crate items and just output metadata in -Z no-codegen mode.
|
||
if tcx.sess.opts.unstable_opts.no_codegen || !tcx.sess.opts.output_types.should_codegen() {
|
||
let ongoing_codegen = start_async_codegen(backend, tcx, target_cpu, metadata, None);
|
||
|
||
ongoing_codegen.codegen_finished(tcx);
|
||
|
||
ongoing_codegen.check_for_errors(tcx.sess);
|
||
|
||
return ongoing_codegen;
|
||
}
|
||
|
||
let cgu_name_builder = &mut CodegenUnitNameBuilder::new(tcx);
|
||
|
||
// Run the monomorphization collector and partition the collected items into
|
||
// codegen units.
|
||
let codegen_units = tcx.collect_and_partition_mono_items(()).1;
|
||
|
||
// Force all codegen_unit queries so they are already either red or green
|
||
// when compile_codegen_unit accesses them. We are not able to re-execute
|
||
// the codegen_unit query from just the DepNode, so an unknown color would
|
||
// lead to having to re-execute compile_codegen_unit, possibly
|
||
// unnecessarily.
|
||
if tcx.dep_graph.is_fully_enabled() {
|
||
for cgu in codegen_units {
|
||
tcx.ensure().codegen_unit(cgu.name());
|
||
}
|
||
}
|
||
|
||
let metadata_module = need_metadata_module.then(|| {
|
||
// Emit compressed metadata object.
|
||
let metadata_cgu_name =
|
||
cgu_name_builder.build_cgu_name(LOCAL_CRATE, &["crate"], Some("metadata")).to_string();
|
||
tcx.sess.time("write_compressed_metadata", || {
|
||
let file_name =
|
||
tcx.output_filenames(()).temp_path(OutputType::Metadata, Some(&metadata_cgu_name));
|
||
let data = create_compressed_metadata_file(
|
||
tcx.sess,
|
||
&metadata,
|
||
&exported_symbols::metadata_symbol_name(tcx),
|
||
);
|
||
if let Err(error) = std::fs::write(&file_name, data) {
|
||
tcx.dcx().emit_fatal(errors::MetadataObjectFileWrite { error });
|
||
}
|
||
CompiledModule {
|
||
name: metadata_cgu_name,
|
||
kind: ModuleKind::Metadata,
|
||
object: Some(file_name),
|
||
dwarf_object: None,
|
||
bytecode: None,
|
||
assembly: None,
|
||
llvm_ir: None,
|
||
}
|
||
})
|
||
});
|
||
|
||
let ongoing_codegen =
|
||
start_async_codegen(backend.clone(), tcx, target_cpu, metadata, metadata_module);
|
||
|
||
// Codegen an allocator shim, if necessary.
|
||
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", || {
|
||
backend.codegen_allocator(
|
||
tcx,
|
||
&llmod_id,
|
||
kind,
|
||
// If allocator_kind is Some then alloc_error_handler_kind must
|
||
// also be Some.
|
||
tcx.alloc_error_handler_kind(()).unwrap(),
|
||
)
|
||
});
|
||
|
||
ongoing_codegen.wait_for_signal_to_codegen_item();
|
||
ongoing_codegen.check_for_errors(tcx.sess);
|
||
|
||
// These modules are generally cheap and won't throw off scheduling.
|
||
let cost = 0;
|
||
submit_codegened_module_to_llvm(
|
||
&backend,
|
||
&ongoing_codegen.coordinator.sender,
|
||
ModuleCodegen { name: llmod_id, module_llvm, kind: ModuleKind::Allocator },
|
||
cost,
|
||
);
|
||
}
|
||
|
||
// For better throughput during parallel processing by LLVM, we used to sort
|
||
// CGUs largest to smallest. This would lead to better thread utilization
|
||
// by, for example, preventing a large CGU from being processed last and
|
||
// having only one LLVM thread working while the rest remained idle.
|
||
//
|
||
// However, this strategy would lead to high memory usage, as it meant the
|
||
// LLVM-IR for all of the largest CGUs would be resident in memory at once.
|
||
//
|
||
// Instead, we can compromise by ordering CGUs such that the largest and
|
||
// smallest are first, second largest and smallest are next, etc. If there
|
||
// are large size variations, this can reduce memory usage significantly.
|
||
let codegen_units: Vec<_> = {
|
||
let mut sorted_cgus = codegen_units.iter().collect::<Vec<_>>();
|
||
sorted_cgus.sort_by_key(|cgu| cmp::Reverse(cgu.size_estimate()));
|
||
|
||
let (first_half, second_half) = sorted_cgus.split_at(sorted_cgus.len() / 2);
|
||
first_half.iter().interleave(second_half.iter().rev()).copied().collect()
|
||
};
|
||
|
||
// Calculate the CGU reuse
|
||
let cgu_reuse = tcx.sess.time("find_cgu_reuse", || {
|
||
codegen_units.iter().map(|cgu| determine_cgu_reuse(tcx, cgu)).collect::<Vec<_>>()
|
||
});
|
||
|
||
crate::assert_module_sources::assert_module_sources(tcx, &|cgu_reuse_tracker| {
|
||
for (i, cgu) in codegen_units.iter().enumerate() {
|
||
let cgu_reuse = cgu_reuse[i];
|
||
cgu_reuse_tracker.set_actual_reuse(cgu.name().as_str(), cgu_reuse);
|
||
}
|
||
});
|
||
|
||
let mut total_codegen_time = Duration::new(0, 0);
|
||
let start_rss = tcx.sess.opts.unstable_opts.time_passes.then(|| get_resident_set_size());
|
||
|
||
// The non-parallel compiler can only translate codegen units to LLVM IR
|
||
// on a single thread, leading to a staircase effect where the N LLVM
|
||
// threads have to wait on the single codegen threads to generate work
|
||
// for them. The parallel compiler does not have this restriction, so
|
||
// we can pre-load the LLVM queue in parallel before handing off
|
||
// coordination to the OnGoingCodegen scheduler.
|
||
//
|
||
// This likely is a temporary measure. Once we don't have to support the
|
||
// non-parallel compiler anymore, we can compile CGUs end-to-end in
|
||
// parallel and get rid of the complicated scheduling logic.
|
||
let mut pre_compiled_cgus = if tcx.sess.threads() > 1 {
|
||
tcx.sess.time("compile_first_CGU_batch", || {
|
||
// Try to find one CGU to compile per thread.
|
||
let cgus: Vec<_> = cgu_reuse
|
||
.iter()
|
||
.enumerate()
|
||
.filter(|&(_, reuse)| reuse == &CguReuse::No)
|
||
.take(tcx.sess.threads())
|
||
.collect();
|
||
|
||
// Compile the found CGUs in parallel.
|
||
let start_time = Instant::now();
|
||
|
||
let pre_compiled_cgus = par_map(cgus, |(i, _)| {
|
||
let module = backend.compile_codegen_unit(tcx, codegen_units[i].name());
|
||
(i, module)
|
||
});
|
||
|
||
total_codegen_time += start_time.elapsed();
|
||
|
||
pre_compiled_cgus
|
||
})
|
||
} else {
|
||
FxHashMap::default()
|
||
};
|
||
|
||
for (i, cgu) in codegen_units.iter().enumerate() {
|
||
ongoing_codegen.wait_for_signal_to_codegen_item();
|
||
ongoing_codegen.check_for_errors(tcx.sess);
|
||
|
||
let cgu_reuse = cgu_reuse[i];
|
||
|
||
match cgu_reuse {
|
||
CguReuse::No => {
|
||
let (module, cost) = if let Some(cgu) = pre_compiled_cgus.remove(&i) {
|
||
cgu
|
||
} else {
|
||
let start_time = Instant::now();
|
||
let module = backend.compile_codegen_unit(tcx, cgu.name());
|
||
total_codegen_time += start_time.elapsed();
|
||
module
|
||
};
|
||
// This will unwind if there are errors, which triggers our `AbortCodegenOnDrop`
|
||
// guard. Unfortunately, just skipping the `submit_codegened_module_to_llvm` makes
|
||
// compilation hang on post-monomorphization errors.
|
||
tcx.dcx().abort_if_errors();
|
||
|
||
submit_codegened_module_to_llvm(
|
||
&backend,
|
||
&ongoing_codegen.coordinator.sender,
|
||
module,
|
||
cost,
|
||
);
|
||
}
|
||
CguReuse::PreLto => {
|
||
submit_pre_lto_module_to_llvm(
|
||
&backend,
|
||
tcx,
|
||
&ongoing_codegen.coordinator.sender,
|
||
CachedModuleCodegen {
|
||
name: cgu.name().to_string(),
|
||
source: cgu.previous_work_product(tcx),
|
||
},
|
||
);
|
||
}
|
||
CguReuse::PostLto => {
|
||
submit_post_lto_module_to_llvm(
|
||
&backend,
|
||
&ongoing_codegen.coordinator.sender,
|
||
CachedModuleCodegen {
|
||
name: cgu.name().to_string(),
|
||
source: cgu.previous_work_product(tcx),
|
||
},
|
||
);
|
||
}
|
||
}
|
||
}
|
||
|
||
ongoing_codegen.codegen_finished(tcx);
|
||
|
||
// Since the main thread is sometimes blocked during codegen, we keep track
|
||
// -Ztime-passes output manually.
|
||
if tcx.sess.opts.unstable_opts.time_passes {
|
||
let end_rss = get_resident_set_size();
|
||
|
||
print_time_passes_entry(
|
||
"codegen_to_LLVM_IR",
|
||
total_codegen_time,
|
||
start_rss.unwrap(),
|
||
end_rss,
|
||
tcx.sess.opts.unstable_opts.time_passes_format,
|
||
);
|
||
}
|
||
|
||
ongoing_codegen.check_for_errors(tcx.sess);
|
||
ongoing_codegen
|
||
}
|
||
|
||
impl CrateInfo {
|
||
pub fn new(tcx: TyCtxt<'_>, target_cpu: String) -> CrateInfo {
|
||
let crate_types = tcx.crate_types().to_vec();
|
||
let exported_symbols = crate_types
|
||
.iter()
|
||
.map(|&c| (c, crate::back::linker::exported_symbols(tcx, c)))
|
||
.collect();
|
||
let linked_symbols =
|
||
crate_types.iter().map(|&c| (c, crate::back::linker::linked_symbols(tcx, c))).collect();
|
||
let local_crate_name = tcx.crate_name(LOCAL_CRATE);
|
||
let crate_attrs = tcx.hir().attrs(rustc_hir::CRATE_HIR_ID);
|
||
let subsystem = attr::first_attr_value_str_by_name(crate_attrs, sym::windows_subsystem);
|
||
let windows_subsystem = subsystem.map(|subsystem| {
|
||
if subsystem != sym::windows && subsystem != sym::console {
|
||
tcx.dcx().emit_fatal(errors::InvalidWindowsSubsystem { subsystem });
|
||
}
|
||
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 mut compiler_builtins = None;
|
||
let mut used_crates: Vec<_> = tcx
|
||
.postorder_cnums(())
|
||
.iter()
|
||
.rev()
|
||
.copied()
|
||
.filter(|&cnum| {
|
||
let link = !tcx.dep_kind(cnum).macros_only();
|
||
if link && tcx.is_compiler_builtins(cnum) {
|
||
compiler_builtins = Some(cnum);
|
||
return false;
|
||
}
|
||
link
|
||
})
|
||
.collect();
|
||
// `compiler_builtins` are always placed last to ensure that they're linked correctly.
|
||
used_crates.extend(compiler_builtins);
|
||
|
||
let crates = tcx.crates(());
|
||
let n_crates = crates.len();
|
||
let mut info = CrateInfo {
|
||
target_cpu,
|
||
crate_types,
|
||
exported_symbols,
|
||
linked_symbols,
|
||
local_crate_name,
|
||
compiler_builtins,
|
||
profiler_runtime: None,
|
||
is_no_builtins: Default::default(),
|
||
native_libraries: Default::default(),
|
||
used_libraries: tcx.native_libraries(LOCAL_CRATE).iter().map(Into::into).collect(),
|
||
crate_name: UnordMap::with_capacity(n_crates),
|
||
used_crates,
|
||
used_crate_source: UnordMap::with_capacity(n_crates),
|
||
dependency_formats: tcx.dependency_formats(()).clone(),
|
||
windows_subsystem,
|
||
natvis_debugger_visualizers: Default::default(),
|
||
};
|
||
|
||
info.native_libraries.reserve(n_crates);
|
||
|
||
for &cnum in crates.iter() {
|
||
info.native_libraries
|
||
.insert(cnum, tcx.native_libraries(cnum).iter().map(Into::into).collect());
|
||
info.crate_name.insert(cnum, tcx.crate_name(cnum));
|
||
|
||
let used_crate_source = tcx.used_crate_source(cnum);
|
||
info.used_crate_source.insert(cnum, used_crate_source.clone());
|
||
if tcx.is_profiler_runtime(cnum) {
|
||
info.profiler_runtime = Some(cnum);
|
||
}
|
||
if tcx.is_no_builtins(cnum) {
|
||
info.is_no_builtins.insert(cnum);
|
||
}
|
||
}
|
||
|
||
// Handle circular dependencies in the standard library.
|
||
// See comment before `add_linked_symbol_object` function for the details.
|
||
// If global LTO is enabled then almost everything (*) is glued into a single object file,
|
||
// so this logic is not necessary and can cause issues on some targets (due to weak lang
|
||
// item symbols being "privatized" to that object file), so we disable it.
|
||
// (*) Native libs, and `#[compiler_builtins]` and `#[no_builtins]` crates are not glued,
|
||
// and we assume that they cannot define weak lang items. This is not currently enforced
|
||
// by the compiler, but that's ok because all this stuff is unstable anyway.
|
||
let target = &tcx.sess.target;
|
||
if !are_upstream_rust_objects_already_included(tcx.sess) {
|
||
let missing_weak_lang_items: FxIndexSet<Symbol> = info
|
||
.used_crates
|
||
.iter()
|
||
.flat_map(|&cnum| tcx.missing_lang_items(cnum))
|
||
.filter(|l| l.is_weak())
|
||
.filter_map(|&l| {
|
||
let name = l.link_name()?;
|
||
lang_items::required(tcx, l).then_some(name)
|
||
})
|
||
.collect();
|
||
let prefix = match (target.is_like_windows, target.arch.as_ref()) {
|
||
(true, "x86") => "_",
|
||
(true, "arm64ec") => "#",
|
||
_ => "",
|
||
};
|
||
|
||
// This loop only adds new items to values of the hash map, so the order in which we
|
||
// iterate over the values is not important.
|
||
#[allow(rustc::potential_query_instability)]
|
||
info.linked_symbols
|
||
.iter_mut()
|
||
.filter(|(crate_type, _)| {
|
||
!matches!(crate_type, CrateType::Rlib | CrateType::Staticlib)
|
||
})
|
||
.for_each(|(_, linked_symbols)| {
|
||
let mut symbols = missing_weak_lang_items
|
||
.iter()
|
||
.map(|item| (format!("{prefix}{item}"), SymbolExportKind::Text))
|
||
.collect::<Vec<_>>();
|
||
symbols.sort_unstable_by(|a, b| a.0.cmp(&b.0));
|
||
linked_symbols.extend(symbols);
|
||
if tcx.allocator_kind(()).is_some() {
|
||
// At least one crate needs a global allocator. This crate may be placed
|
||
// after the crate that defines it in the linker order, in which case some
|
||
// linkers return an error. By adding the global allocator shim methods to
|
||
// the linked_symbols list, linking the generated symbols.o will ensure that
|
||
// circular dependencies involving the global allocator don't lead to linker
|
||
// errors.
|
||
linked_symbols.extend(ALLOCATOR_METHODS.iter().map(|method| {
|
||
(
|
||
format!("{prefix}{}", global_fn_name(method.name).as_str()),
|
||
SymbolExportKind::Text,
|
||
)
|
||
}));
|
||
}
|
||
});
|
||
}
|
||
|
||
let embed_visualizers = tcx.crate_types().iter().any(|&crate_type| match crate_type {
|
||
CrateType::Executable | CrateType::Dylib | CrateType::Cdylib => {
|
||
// These are crate types for which we invoke the linker and can embed
|
||
// NatVis visualizers.
|
||
true
|
||
}
|
||
CrateType::ProcMacro => {
|
||
// We could embed NatVis for proc macro crates too (to improve the debugging
|
||
// experience for them) but it does not seem like a good default, since
|
||
// this is a rare use case and we don't want to slow down the common case.
|
||
false
|
||
}
|
||
CrateType::Staticlib | CrateType::Rlib => {
|
||
// We don't invoke the linker for these, so we don't need to collect the NatVis for them.
|
||
false
|
||
}
|
||
});
|
||
|
||
if target.is_like_msvc && embed_visualizers {
|
||
info.natvis_debugger_visualizers =
|
||
collect_debugger_visualizers_transitive(tcx, DebuggerVisualizerType::Natvis);
|
||
}
|
||
|
||
info
|
||
}
|
||
}
|
||
|
||
pub fn provide(providers: &mut Providers) {
|
||
providers.backend_optimization_level = |tcx, cratenum| {
|
||
let for_speed = match tcx.sess.opts.optimize {
|
||
// If globally no optimisation is done, #[optimize] has no effect.
|
||
//
|
||
// This is done because if we ended up "upgrading" to `-O2` here, we’d populate the
|
||
// pass manager and it is likely that some module-wide passes (such as inliner or
|
||
// cross-function constant propagation) would ignore the `optnone` annotation we put
|
||
// on the functions, thus necessarily involving these functions into optimisations.
|
||
config::OptLevel::No => return config::OptLevel::No,
|
||
// If globally optimise-speed is already specified, just use that level.
|
||
config::OptLevel::Less => return config::OptLevel::Less,
|
||
config::OptLevel::Default => return config::OptLevel::Default,
|
||
config::OptLevel::Aggressive => return config::OptLevel::Aggressive,
|
||
// If globally optimize-for-size has been requested, use -O2 instead (if optimize(size)
|
||
// are present).
|
||
config::OptLevel::Size => config::OptLevel::Default,
|
||
config::OptLevel::SizeMin => config::OptLevel::Default,
|
||
};
|
||
|
||
let (defids, _) = tcx.collect_and_partition_mono_items(cratenum);
|
||
|
||
let any_for_speed = defids.items().any(|id| {
|
||
let CodegenFnAttrs { optimize, .. } = tcx.codegen_fn_attrs(*id);
|
||
match optimize {
|
||
attr::OptimizeAttr::None | attr::OptimizeAttr::Size => false,
|
||
attr::OptimizeAttr::Speed => true,
|
||
}
|
||
});
|
||
|
||
if any_for_speed {
|
||
return for_speed;
|
||
}
|
||
|
||
tcx.sess.opts.optimize
|
||
};
|
||
}
|
||
|
||
pub fn determine_cgu_reuse<'tcx>(tcx: TyCtxt<'tcx>, cgu: &CodegenUnit<'tcx>) -> CguReuse {
|
||
if !tcx.dep_graph.is_fully_enabled() {
|
||
return CguReuse::No;
|
||
}
|
||
|
||
let work_product_id = &cgu.work_product_id();
|
||
if tcx.dep_graph.previous_work_product(work_product_id).is_none() {
|
||
// We don't have anything cached for this CGU. This can happen
|
||
// if the CGU did not exist in the previous session.
|
||
return CguReuse::No;
|
||
}
|
||
|
||
// Try to mark the CGU as green. If it we can do so, it means that nothing
|
||
// affecting the LLVM module has changed and we can re-use a cached version.
|
||
// If we compile with any kind of LTO, this means we can re-use the bitcode
|
||
// of the Pre-LTO stage (possibly also the Post-LTO version but we'll only
|
||
// know that later). If we are not doing LTO, there is only one optimized
|
||
// version of each module, so we re-use that.
|
||
let dep_node = cgu.codegen_dep_node(tcx);
|
||
assert!(
|
||
!tcx.dep_graph.dep_node_exists(&dep_node),
|
||
"CompileCodegenUnit dep-node for CGU `{}` already exists before marking.",
|
||
cgu.name()
|
||
);
|
||
|
||
if tcx.try_mark_green(&dep_node) {
|
||
// We can re-use either the pre- or the post-thinlto state. If no LTO is
|
||
// being performed then we can use post-LTO artifacts, otherwise we must
|
||
// reuse pre-LTO artifacts
|
||
match compute_per_cgu_lto_type(
|
||
&tcx.sess.lto(),
|
||
&tcx.sess.opts,
|
||
tcx.crate_types(),
|
||
ModuleKind::Regular,
|
||
) {
|
||
ComputedLtoType::No => CguReuse::PostLto,
|
||
_ => CguReuse::PreLto,
|
||
}
|
||
} else {
|
||
CguReuse::No
|
||
}
|
||
}
|