36f18f2d3a
`codegen_allocator` and `write_metadata` mutate the underlying LLVM module. As such, it makes sense for these two functions to receive a mutable reference to the module (as opposed to an immutable one).
999 lines
36 KiB
Rust
999 lines
36 KiB
Rust
//! Codegen the completed AST to the LLVM IR.
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//!
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//! Some functions here, such as codegen_block and codegen_expr, return a value --
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//! the result of the codegen to LLVM -- while others, such as codegen_fn
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//! and mono_item, are called only for the side effect of adding a
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//! particular definition to the LLVM IR output we're producing.
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//!
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//! Hopefully useful general knowledge about codegen:
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//!
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//! * There's no way to find out the `Ty` type of a Value. Doing so
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//! would be "trying to get the eggs out of an omelette" (credit:
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//! pcwalton). You can, instead, find out its `llvm::Type` by calling `val_ty`,
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//! but one `llvm::Type` corresponds to many `Ty`s; for instance, `tup(int, int,
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//! int)` and `rec(x=int, y=int, z=int)` will have the same `llvm::Type`.
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use crate::{ModuleCodegen, ModuleKind, CachedModuleCodegen};
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use rustc::dep_graph::cgu_reuse_tracker::CguReuse;
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use rustc::hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
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use rustc::middle::lang_items::StartFnLangItem;
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use rustc::middle::weak_lang_items;
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use rustc::mir::mono::{Stats, CodegenUnitNameBuilder};
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use rustc::ty::{self, Ty, TyCtxt};
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use rustc::ty::layout::{self, Align, TyLayout, LayoutOf, VariantIdx, HasTyCtxt};
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use rustc::ty::query::Providers;
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use rustc::middle::cstore::{self, LinkagePreference};
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use rustc::util::common::{time, print_time_passes_entry};
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use rustc::util::profiling::ProfileCategory;
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use rustc::session::config::{self, EntryFnType, Lto};
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use rustc::session::Session;
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use rustc_mir::monomorphize::item::DefPathBasedNames;
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use rustc::util::time_graph;
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use rustc_mir::monomorphize::Instance;
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use rustc_mir::monomorphize::partitioning::{CodegenUnit, CodegenUnitExt};
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use rustc::util::nodemap::FxHashMap;
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use rustc_data_structures::indexed_vec::Idx;
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use rustc_data_structures::sync::Lrc;
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use rustc_codegen_utils::{symbol_names_test, check_for_rustc_errors_attr};
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use rustc::ty::layout::{FAT_PTR_ADDR, FAT_PTR_EXTRA};
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use crate::mir::place::PlaceRef;
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use crate::back::write::{OngoingCodegen, start_async_codegen, submit_pre_lto_module_to_llvm,
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submit_post_lto_module_to_llvm};
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use crate::{MemFlags, CrateInfo};
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use crate::callee;
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use crate::common::{RealPredicate, TypeKind, IntPredicate};
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use crate::meth;
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use crate::mir;
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use crate::mono_item::MonoItem;
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use crate::traits::*;
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use std::any::Any;
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use std::cmp;
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use std::ops::{Deref, DerefMut};
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use std::time::{Instant, Duration};
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use std::sync::mpsc;
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use syntax_pos::Span;
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use syntax::attr;
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use rustc::hir;
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use crate::mir::operand::OperandValue;
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use std::marker::PhantomData;
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pub struct StatRecorder<'a, 'tcx, Cx: 'a + CodegenMethods<'tcx>> {
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cx: &'a Cx,
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name: Option<String>,
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istart: usize,
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_marker: PhantomData<&'tcx ()>,
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}
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impl<'a, 'tcx, Cx: CodegenMethods<'tcx>> StatRecorder<'a, 'tcx, Cx> {
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pub fn new(cx: &'a Cx, name: String) -> Self {
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let istart = cx.stats().borrow().n_llvm_insns;
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StatRecorder {
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cx,
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name: Some(name),
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istart,
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_marker: PhantomData,
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}
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}
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}
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impl<'a, 'tcx, Cx: CodegenMethods<'tcx>> Drop for StatRecorder<'a, 'tcx, Cx> {
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fn drop(&mut self) {
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if self.cx.sess().codegen_stats() {
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let mut stats = self.cx.stats().borrow_mut();
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let iend = stats.n_llvm_insns;
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stats.fn_stats.push((self.name.take().unwrap(), iend - self.istart));
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stats.n_fns += 1;
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// Reset LLVM insn count to avoid compound costs.
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stats.n_llvm_insns = self.istart;
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}
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}
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}
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pub fn bin_op_to_icmp_predicate(op: hir::BinOpKind,
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signed: bool)
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-> IntPredicate {
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match op {
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hir::BinOpKind::Eq => IntPredicate::IntEQ,
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hir::BinOpKind::Ne => IntPredicate::IntNE,
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hir::BinOpKind::Lt => if signed { IntPredicate::IntSLT } else { IntPredicate::IntULT },
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hir::BinOpKind::Le => if signed { IntPredicate::IntSLE } else { IntPredicate::IntULE },
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hir::BinOpKind::Gt => if signed { IntPredicate::IntSGT } else { IntPredicate::IntUGT },
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hir::BinOpKind::Ge => if signed { IntPredicate::IntSGE } else { IntPredicate::IntUGE },
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op => {
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bug!("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: hir::BinOpKind) -> RealPredicate {
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match op {
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hir::BinOpKind::Eq => RealPredicate::RealOEQ,
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hir::BinOpKind::Ne => RealPredicate::RealUNE,
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hir::BinOpKind::Lt => RealPredicate::RealOLT,
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hir::BinOpKind::Le => RealPredicate::RealOLE,
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hir::BinOpKind::Gt => RealPredicate::RealOGT,
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hir::BinOpKind::Ge => RealPredicate::RealOGE,
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op => {
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bug!("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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pub fn compare_simd_types<'a, 'tcx: 'a, 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: hir::BinOpKind
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) -> Bx::Value {
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let signed = match t.sty {
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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 funny. It is intended for use
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/// in an upcast, where the new vtable for an object will be derived
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/// from the old one.
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pub fn unsized_info<'tcx, Cx: CodegenMethods<'tcx>>(
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cx: &Cx,
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source: Ty<'tcx>,
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target: Ty<'tcx>,
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old_info: Option<Cx::Value>,
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) -> Cx::Value {
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let (source, target) = cx.tcx().struct_lockstep_tails(source, target);
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match (&source.sty, &target.sty) {
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(&ty::Array(_, len), &ty::Slice(_)) => {
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cx.const_usize(len.unwrap_usize(cx.tcx()))
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}
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(&ty::Dynamic(..), &ty::Dynamic(..)) => {
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// For now, upcasts are limited to changes in marker
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// traits, and hence never actually require an actual
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// change to the vtable.
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old_info.expect("unsized_info: missing old info for trait upcast")
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}
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(_, &ty::Dynamic(ref data, ..)) => {
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let vtable_ptr = cx.layout_of(cx.tcx().mk_mut_ptr(target))
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.field(cx, FAT_PTR_EXTRA);
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cx.const_ptrcast(meth::get_vtable(cx, source, data.principal()),
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cx.backend_type(vtable_ptr))
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}
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_ => bug!("unsized_info: invalid unsizing {:?} -> {:?}",
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source,
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target),
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}
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}
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/// Coerce `src` to `dst_ty`. `src_ty` must be a thin pointer.
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pub fn unsize_thin_ptr<'a, 'tcx: 'a, 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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) -> (Bx::Value, Bx::Value) {
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debug!("unsize_thin_ptr: {:?} => {:?}", src_ty, dst_ty);
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match (&src_ty.sty, &dst_ty.sty) {
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(&ty::Ref(_, a, _),
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&ty::Ref(_, b, _)) |
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(&ty::Ref(_, a, _),
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&ty::RawPtr(ty::TypeAndMut { ty: b, .. })) |
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(&ty::RawPtr(ty::TypeAndMut { ty: a, .. }),
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&ty::RawPtr(ty::TypeAndMut { ty: b, .. })) => {
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assert!(bx.cx().type_is_sized(a));
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let ptr_ty = bx.cx().type_ptr_to(bx.cx().backend_type(bx.cx().layout_of(b)));
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(bx.pointercast(src, ptr_ty), unsized_info(bx.cx(), a, b, None))
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}
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(&ty::Adt(def_a, _), &ty::Adt(def_b, _)) if def_a.is_box() && def_b.is_box() => {
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let (a, b) = (src_ty.boxed_ty(), dst_ty.boxed_ty());
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assert!(bx.cx().type_is_sized(a));
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let ptr_ty = bx.cx().type_ptr_to(bx.cx().backend_type(bx.cx().layout_of(b)));
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(bx.pointercast(src, ptr_ty), unsized_info(bx.cx(), a, b, None))
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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);
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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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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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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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if src_f.is_zst() {
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continue;
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}
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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_thin_ptr(bx, src, src_f.ty, dst_f.ty));
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}
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let (lldata, llextra) = result.unwrap();
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// HACK(eddyb) have to bitcast pointers until LLVM removes pointee types.
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(bx.bitcast(lldata, bx.cx().scalar_pair_element_backend_type(dst_layout, 0, true)),
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bx.bitcast(llextra, bx.cx().scalar_pair_element_backend_type(dst_layout, 1, true)))
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}
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_ => bug!("unsize_thin_ptr: called on bad types"),
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}
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}
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/// Coerce `src`, which is a reference to a value of type `src_ty`,
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/// to a value of type `dst_ty` and store the result in `dst`
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pub fn coerce_unsized_into<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
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bx: &mut Bx,
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src: PlaceRef<'tcx, Bx::Value>,
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dst: PlaceRef<'tcx, Bx::Value>
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) {
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let src_ty = src.layout.ty;
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let dst_ty = dst.layout.ty;
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let mut coerce_ptr = || {
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let (base, info) = match bx.load_operand(src).val {
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OperandValue::Pair(base, info) => {
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// fat-ptr to fat-ptr unsize preserves the vtable
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// i.e., &'a fmt::Debug+Send => &'a fmt::Debug
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// So we need to pointercast the base to ensure
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// the types match up.
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let thin_ptr = dst.layout.field(bx.cx(), FAT_PTR_ADDR);
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(bx.pointercast(base, bx.cx().backend_type(thin_ptr)), info)
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}
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OperandValue::Immediate(base) => {
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unsize_thin_ptr(bx, base, src_ty, dst_ty)
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}
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OperandValue::Ref(..) => bug!()
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};
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OperandValue::Pair(base, info).store(bx, dst);
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};
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match (&src_ty.sty, &dst_ty.sty) {
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(&ty::Ref(..), &ty::Ref(..)) |
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(&ty::Ref(..), &ty::RawPtr(..)) |
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(&ty::RawPtr(..), &ty::RawPtr(..)) => {
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coerce_ptr()
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}
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(&ty::Adt(def_a, _), &ty::Adt(def_b, _)) if def_a.is_box() && def_b.is_box() => {
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coerce_ptr()
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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);
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for i in 0..def_a.variants[VariantIdx::new(0)].fields.len() {
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let src_f = src.project_field(bx, i);
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let dst_f = dst.project_field(bx, i);
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if dst_f.layout.is_zst() {
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continue;
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}
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if src_f.layout.ty == dst_f.layout.ty {
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memcpy_ty(bx, dst_f.llval, dst_f.align, src_f.llval, src_f.align,
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src_f.layout, MemFlags::empty());
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} else {
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coerce_unsized_into(bx, src_f, dst_f);
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}
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}
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}
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_ => bug!("coerce_unsized_into: invalid coercion {:?} -> {:?}",
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src_ty,
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dst_ty),
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}
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}
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pub fn cast_shift_expr_rhs<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
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bx: &mut Bx,
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op: hir::BinOpKind,
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lhs: Bx::Value,
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rhs: Bx::Value
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) -> Bx::Value {
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cast_shift_rhs(bx, op, lhs, rhs)
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}
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fn cast_shift_rhs<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
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bx: &mut Bx,
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op: hir::BinOpKind,
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lhs: Bx::Value,
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rhs: Bx::Value,
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) -> Bx::Value {
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// Shifts may have any size int on the rhs
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if op.is_shift() {
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let mut rhs_llty = bx.cx().val_ty(rhs);
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let mut lhs_llty = bx.cx().val_ty(lhs);
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if bx.cx().type_kind(rhs_llty) == TypeKind::Vector {
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rhs_llty = bx.cx().element_type(rhs_llty)
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}
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if bx.cx().type_kind(lhs_llty) == TypeKind::Vector {
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lhs_llty = bx.cx().element_type(lhs_llty)
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}
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let rhs_sz = bx.cx().int_width(rhs_llty);
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let lhs_sz = bx.cx().int_width(lhs_llty);
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if lhs_sz < rhs_sz {
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bx.trunc(rhs, lhs_llty)
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} else if lhs_sz > rhs_sz {
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// FIXME (#1877: If in the future shifting by negative
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// values is no longer undefined then this is wrong.
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bx.zext(rhs, lhs_llty)
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} else {
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rhs
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}
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} else {
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rhs
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}
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}
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/// Returns `true` if this session's target will use SEH-based unwinding.
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///
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/// This is only true for MSVC targets, and even then the 64-bit MSVC target
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/// currently uses SEH-ish unwinding with DWARF info tables to the side (same as
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/// 64-bit MinGW) instead of "full SEH".
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pub fn wants_msvc_seh(sess: &Session) -> bool {
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sess.target.target.options.is_like_msvc
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||
}
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pub fn from_immediate<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
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bx: &mut Bx,
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val: Bx::Value
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) -> Bx::Value {
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if bx.cx().val_ty(val) == bx.cx().type_i1() {
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bx.zext(val, bx.cx().type_i8())
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} else {
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val
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||
}
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||
}
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pub fn to_immediate<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
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bx: &mut Bx,
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val: Bx::Value,
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layout: layout::TyLayout,
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||
) -> Bx::Value {
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||
if let layout::Abi::Scalar(ref scalar) = layout.abi {
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return to_immediate_scalar(bx, val, scalar);
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||
}
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val
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||
}
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pub fn to_immediate_scalar<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
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bx: &mut Bx,
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||
val: Bx::Value,
|
||
scalar: &layout::Scalar,
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||
) -> Bx::Value {
|
||
if scalar.is_bool() {
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return bx.trunc(val, bx.cx().type_i1());
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||
}
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val
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||
}
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pub fn memcpy_ty<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
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bx: &mut Bx,
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dst: Bx::Value,
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dst_align: Align,
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src: Bx::Value,
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src_align: Align,
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layout: TyLayout<'tcx>,
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flags: MemFlags,
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) {
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let size = layout.size.bytes();
|
||
if size == 0 {
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return;
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||
}
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bx.memcpy(dst, dst_align, src, src_align, bx.cx().const_usize(size), flags);
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||
}
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pub fn codegen_instance<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
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cx: &'a Bx::CodegenCx,
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instance: Instance<'tcx>,
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) {
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let _s = if cx.sess().codegen_stats() {
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let mut instance_name = String::new();
|
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DefPathBasedNames::new(cx.tcx(), true, true)
|
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.push_def_path(instance.def_id(), &mut instance_name);
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Some(StatRecorder::new(cx, instance_name))
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||
} else {
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None
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||
};
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||
|
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// this is an info! to allow collecting monomorphization statistics
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||
// and to allow finding the last function before LLVM aborts from
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// release builds.
|
||
info!("codegen_instance({})", instance);
|
||
|
||
let sig = instance.fn_sig(cx.tcx());
|
||
let sig = cx.tcx().normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), &sig);
|
||
|
||
let lldecl = cx.instances().borrow().get(&instance).cloned().unwrap_or_else(||
|
||
bug!("Instance `{:?}` not already declared", instance));
|
||
|
||
cx.stats().borrow_mut().n_closures += 1;
|
||
|
||
let mir = cx.tcx().instance_mir(instance.def);
|
||
mir::codegen_mir::<Bx>(cx, lldecl, &mir, instance, sig);
|
||
}
|
||
|
||
/// Creates the `main` function which will initialize the rust runtime and call
|
||
/// users main function.
|
||
pub fn maybe_create_entry_wrapper<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
|
||
cx: &'a Bx::CodegenCx
|
||
) {
|
||
let (main_def_id, span) = match cx.tcx().entry_fn(LOCAL_CRATE) {
|
||
Some((def_id, _)) => { (def_id, cx.tcx().def_span(def_id)) },
|
||
None => return,
|
||
};
|
||
|
||
let instance = Instance::mono(cx.tcx(), main_def_id);
|
||
|
||
if !cx.codegen_unit().contains_item(&MonoItem::Fn(instance)) {
|
||
// We want to create the wrapper in the same codegen unit as Rust's main
|
||
// function.
|
||
return;
|
||
}
|
||
|
||
let main_llfn = cx.get_fn(instance);
|
||
|
||
let et = cx.tcx().entry_fn(LOCAL_CRATE).map(|e| e.1);
|
||
match et {
|
||
Some(EntryFnType::Main) => create_entry_fn::<Bx>(cx, span, main_llfn, main_def_id, true),
|
||
Some(EntryFnType::Start) => create_entry_fn::<Bx>(cx, span, main_llfn, main_def_id, false),
|
||
None => {} // Do nothing.
|
||
}
|
||
|
||
fn create_entry_fn<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
|
||
cx: &'a Bx::CodegenCx,
|
||
sp: Span,
|
||
rust_main: Bx::Value,
|
||
rust_main_def_id: DefId,
|
||
use_start_lang_item: bool,
|
||
) {
|
||
let llfty =
|
||
cx.type_func(&[cx.type_int(), cx.type_ptr_to(cx.type_i8p())], cx.type_int());
|
||
|
||
let main_ret_ty = cx.tcx().fn_sig(rust_main_def_id).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().erase_regions(
|
||
&main_ret_ty.no_bound_vars().unwrap(),
|
||
);
|
||
|
||
if cx.get_defined_value("main").is_some() {
|
||
// FIXME: We should be smart and show a better diagnostic here.
|
||
cx.sess().struct_span_err(sp, "entry symbol `main` defined multiple times")
|
||
.help("did you use #[no_mangle] on `fn main`? Use #[start] instead")
|
||
.emit();
|
||
cx.sess().abort_if_errors();
|
||
bug!();
|
||
}
|
||
let llfn = cx.declare_cfn("main", llfty);
|
||
|
||
// `main` should respect same config for frame pointer elimination as rest of code
|
||
cx.set_frame_pointer_elimination(llfn);
|
||
cx.apply_target_cpu_attr(llfn);
|
||
|
||
let mut bx = Bx::new_block(&cx, llfn, "top");
|
||
|
||
bx.insert_reference_to_gdb_debug_scripts_section_global();
|
||
|
||
// Params from native main() used as args for rust start function
|
||
let param_argc = cx.get_param(llfn, 0);
|
||
let param_argv = cx.get_param(llfn, 1);
|
||
let arg_argc = bx.intcast(param_argc, cx.type_isize(), true);
|
||
let arg_argv = param_argv;
|
||
|
||
let (start_fn, args) = if use_start_lang_item {
|
||
let start_def_id = cx.tcx().require_lang_item(StartFnLangItem);
|
||
let start_fn = callee::resolve_and_get_fn(
|
||
cx,
|
||
start_def_id,
|
||
cx.tcx().intern_substs(&[main_ret_ty.into()]),
|
||
);
|
||
(start_fn, vec![bx.pointercast(rust_main, cx.type_ptr_to(cx.type_i8p())),
|
||
arg_argc, arg_argv])
|
||
} else {
|
||
debug!("using user-defined start fn");
|
||
(rust_main, vec![arg_argc, arg_argv])
|
||
};
|
||
|
||
let result = bx.call(start_fn, &args, None);
|
||
let cast = bx.intcast(result, cx.type_int(), true);
|
||
bx.ret(cast);
|
||
}
|
||
}
|
||
|
||
pub const CODEGEN_WORKER_ID: usize = ::std::usize::MAX;
|
||
pub const CODEGEN_WORKER_TIMELINE: time_graph::TimelineId =
|
||
time_graph::TimelineId(CODEGEN_WORKER_ID);
|
||
pub const CODEGEN_WORK_PACKAGE_KIND: time_graph::WorkPackageKind =
|
||
time_graph::WorkPackageKind(&["#DE9597", "#FED1D3", "#FDC5C7", "#B46668", "#88494B"]);
|
||
|
||
|
||
pub fn codegen_crate<B: ExtraBackendMethods>(
|
||
backend: B,
|
||
tcx: TyCtxt<'a, 'tcx, 'tcx>,
|
||
rx: mpsc::Receiver<Box<dyn Any + Send>>
|
||
) -> OngoingCodegen<B> {
|
||
|
||
check_for_rustc_errors_attr(tcx);
|
||
|
||
let cgu_name_builder = &mut CodegenUnitNameBuilder::new(tcx);
|
||
|
||
// Codegen the metadata.
|
||
tcx.sess.profiler(|p| p.start_activity(ProfileCategory::Codegen));
|
||
|
||
let metadata_cgu_name = cgu_name_builder.build_cgu_name(LOCAL_CRATE,
|
||
&["crate"],
|
||
Some("metadata")).as_str()
|
||
.to_string();
|
||
let mut metadata_llvm_module = backend.new_metadata(tcx, &metadata_cgu_name);
|
||
let metadata = time(tcx.sess, "write metadata", || {
|
||
backend.write_metadata(tcx, &mut metadata_llvm_module)
|
||
});
|
||
tcx.sess.profiler(|p| p.end_activity(ProfileCategory::Codegen));
|
||
|
||
let metadata_module = ModuleCodegen {
|
||
name: metadata_cgu_name,
|
||
module_llvm: metadata_llvm_module,
|
||
kind: ModuleKind::Metadata,
|
||
};
|
||
|
||
let time_graph = if tcx.sess.opts.debugging_opts.codegen_time_graph {
|
||
Some(time_graph::TimeGraph::new())
|
||
} else {
|
||
None
|
||
};
|
||
|
||
// Skip crate items and just output metadata in -Z no-codegen mode.
|
||
if tcx.sess.opts.debugging_opts.no_codegen ||
|
||
!tcx.sess.opts.output_types.should_codegen() {
|
||
let ongoing_codegen = start_async_codegen(
|
||
backend,
|
||
tcx,
|
||
time_graph,
|
||
metadata,
|
||
rx,
|
||
1);
|
||
|
||
ongoing_codegen.submit_pre_codegened_module_to_llvm(tcx, metadata_module);
|
||
ongoing_codegen.codegen_finished(tcx);
|
||
|
||
assert_and_save_dep_graph(tcx);
|
||
|
||
ongoing_codegen.check_for_errors(tcx.sess);
|
||
|
||
return ongoing_codegen;
|
||
}
|
||
|
||
// Run the monomorphization collector and partition the collected items into
|
||
// codegen units.
|
||
let codegen_units = tcx.collect_and_partition_mono_items(LOCAL_CRATE).1;
|
||
let codegen_units = (*codegen_units).clone();
|
||
|
||
// 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.codegen_unit(cgu.name().clone());
|
||
}
|
||
}
|
||
|
||
let ongoing_codegen = start_async_codegen(
|
||
backend.clone(),
|
||
tcx,
|
||
time_graph.clone(),
|
||
metadata,
|
||
rx,
|
||
codegen_units.len());
|
||
let ongoing_codegen = AbortCodegenOnDrop::<B>(Some(ongoing_codegen));
|
||
|
||
// 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.sess.dependency_formats.borrow()
|
||
.iter()
|
||
.any(|(_, list)| {
|
||
use rustc::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.sess.allocator_kind.get() {
|
||
let llmod_id = cgu_name_builder.build_cgu_name(LOCAL_CRATE,
|
||
&["crate"],
|
||
Some("allocator")).as_str()
|
||
.to_string();
|
||
let mut modules = backend.new_metadata(tcx, &llmod_id);
|
||
time(tcx.sess, "write allocator module", || {
|
||
backend.codegen_allocator(tcx, &mut modules, kind)
|
||
});
|
||
|
||
Some(ModuleCodegen {
|
||
name: llmod_id,
|
||
module_llvm: modules,
|
||
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, metadata_module);
|
||
|
||
// We sort the codegen units by size. This way we can schedule work for LLVM
|
||
// a bit more efficiently.
|
||
let codegen_units = {
|
||
let mut codegen_units = codegen_units;
|
||
codegen_units.sort_by_cached_key(|cgu| cmp::Reverse(cgu.size_estimate()));
|
||
codegen_units
|
||
};
|
||
|
||
let mut total_codegen_time = Duration::new(0, 0);
|
||
let mut all_stats = Stats::default();
|
||
|
||
for cgu in codegen_units.into_iter() {
|
||
ongoing_codegen.wait_for_signal_to_codegen_item();
|
||
ongoing_codegen.check_for_errors(tcx.sess);
|
||
|
||
let cgu_reuse = determine_cgu_reuse(tcx, &cgu);
|
||
tcx.sess.cgu_reuse_tracker.set_actual_reuse(&cgu.name().as_str(), cgu_reuse);
|
||
|
||
match cgu_reuse {
|
||
CguReuse::No => {
|
||
let _timing_guard = time_graph.as_ref().map(|time_graph| {
|
||
time_graph.start(CODEGEN_WORKER_TIMELINE,
|
||
CODEGEN_WORK_PACKAGE_KIND,
|
||
&format!("codegen {}", cgu.name()))
|
||
});
|
||
let start_time = Instant::now();
|
||
let stats = backend.compile_codegen_unit(tcx, *cgu.name());
|
||
all_stats.extend(stats);
|
||
total_codegen_time += start_time.elapsed();
|
||
false
|
||
}
|
||
CguReuse::PreLto => {
|
||
submit_pre_lto_module_to_llvm(&backend, tcx, CachedModuleCodegen {
|
||
name: cgu.name().to_string(),
|
||
source: cgu.work_product(tcx),
|
||
});
|
||
true
|
||
}
|
||
CguReuse::PostLto => {
|
||
submit_post_lto_module_to_llvm(&backend, tcx, CachedModuleCodegen {
|
||
name: cgu.name().to_string(),
|
||
source: cgu.work_product(tcx),
|
||
});
|
||
true
|
||
}
|
||
};
|
||
}
|
||
|
||
ongoing_codegen.codegen_finished(tcx);
|
||
|
||
// Since the main thread is sometimes blocked during codegen, we keep track
|
||
// -Ztime-passes output manually.
|
||
print_time_passes_entry(tcx.sess.time_passes(),
|
||
"codegen to LLVM IR",
|
||
total_codegen_time);
|
||
|
||
::rustc_incremental::assert_module_sources::assert_module_sources(tcx);
|
||
|
||
symbol_names_test::report_symbol_names(tcx);
|
||
|
||
if tcx.sess.codegen_stats() {
|
||
println!("--- codegen stats ---");
|
||
println!("n_glues_created: {}", all_stats.n_glues_created);
|
||
println!("n_null_glues: {}", all_stats.n_null_glues);
|
||
println!("n_real_glues: {}", all_stats.n_real_glues);
|
||
|
||
println!("n_fns: {}", all_stats.n_fns);
|
||
println!("n_inlines: {}", all_stats.n_inlines);
|
||
println!("n_closures: {}", all_stats.n_closures);
|
||
println!("fn stats:");
|
||
all_stats.fn_stats.sort_by_key(|&(_, insns)| insns);
|
||
for &(ref name, insns) in all_stats.fn_stats.iter() {
|
||
println!("{} insns, {}", insns, *name);
|
||
}
|
||
}
|
||
|
||
if tcx.sess.count_llvm_insns() {
|
||
for (k, v) in all_stats.llvm_insns.iter() {
|
||
println!("{:7} {}", *v, *k);
|
||
}
|
||
}
|
||
|
||
ongoing_codegen.check_for_errors(tcx.sess);
|
||
|
||
assert_and_save_dep_graph(tcx);
|
||
ongoing_codegen.into_inner()
|
||
}
|
||
|
||
/// A curious wrapper structure whose only purpose is to call `codegen_aborted`
|
||
/// when it's dropped abnormally.
|
||
///
|
||
/// In the process of working on rust-lang/rust#55238 a mysterious segfault was
|
||
/// stumbled upon. The segfault was never reproduced locally, but it was
|
||
/// suspected to be related to the fact that codegen worker threads were
|
||
/// sticking around by the time the main thread was exiting, causing issues.
|
||
///
|
||
/// This structure is an attempt to fix that issue where the `codegen_aborted`
|
||
/// message will block until all workers have finished. This should ensure that
|
||
/// even if the main codegen thread panics we'll wait for pending work to
|
||
/// complete before returning from the main thread, hopefully avoiding
|
||
/// segfaults.
|
||
///
|
||
/// If you see this comment in the code, then it means that this workaround
|
||
/// worked! We may yet one day track down the mysterious cause of that
|
||
/// segfault...
|
||
struct AbortCodegenOnDrop<B: ExtraBackendMethods>(Option<OngoingCodegen<B>>);
|
||
|
||
impl<B: ExtraBackendMethods> AbortCodegenOnDrop<B> {
|
||
fn into_inner(mut self) -> OngoingCodegen<B> {
|
||
self.0.take().unwrap()
|
||
}
|
||
}
|
||
|
||
impl<B: ExtraBackendMethods> Deref for AbortCodegenOnDrop<B> {
|
||
type Target = OngoingCodegen<B>;
|
||
|
||
fn deref(&self) -> &OngoingCodegen<B> {
|
||
self.0.as_ref().unwrap()
|
||
}
|
||
}
|
||
|
||
impl<B: ExtraBackendMethods> DerefMut for AbortCodegenOnDrop<B> {
|
||
fn deref_mut(&mut self) -> &mut OngoingCodegen<B> {
|
||
self.0.as_mut().unwrap()
|
||
}
|
||
}
|
||
|
||
impl<B: ExtraBackendMethods> Drop for AbortCodegenOnDrop<B> {
|
||
fn drop(&mut self) {
|
||
if let Some(codegen) = self.0.take() {
|
||
codegen.codegen_aborted();
|
||
}
|
||
}
|
||
}
|
||
|
||
fn assert_and_save_dep_graph<'ll, 'tcx>(tcx: TyCtxt<'ll, 'tcx, 'tcx>) {
|
||
time(tcx.sess,
|
||
"assert dep graph",
|
||
|| ::rustc_incremental::assert_dep_graph(tcx));
|
||
|
||
time(tcx.sess,
|
||
"serialize dep graph",
|
||
|| ::rustc_incremental::save_dep_graph(tcx));
|
||
}
|
||
|
||
impl CrateInfo {
|
||
pub fn new(tcx: TyCtxt) -> CrateInfo {
|
||
let mut info = CrateInfo {
|
||
panic_runtime: None,
|
||
compiler_builtins: None,
|
||
profiler_runtime: None,
|
||
sanitizer_runtime: None,
|
||
is_no_builtins: Default::default(),
|
||
native_libraries: Default::default(),
|
||
used_libraries: tcx.native_libraries(LOCAL_CRATE),
|
||
link_args: tcx.link_args(LOCAL_CRATE),
|
||
crate_name: Default::default(),
|
||
used_crates_dynamic: cstore::used_crates(tcx, LinkagePreference::RequireDynamic),
|
||
used_crates_static: cstore::used_crates(tcx, LinkagePreference::RequireStatic),
|
||
used_crate_source: Default::default(),
|
||
wasm_imports: Default::default(),
|
||
lang_item_to_crate: Default::default(),
|
||
missing_lang_items: Default::default(),
|
||
};
|
||
let lang_items = tcx.lang_items();
|
||
|
||
let load_wasm_items = tcx.sess.crate_types.borrow()
|
||
.iter()
|
||
.any(|c| *c != config::CrateType::Rlib) &&
|
||
tcx.sess.opts.target_triple.triple() == "wasm32-unknown-unknown";
|
||
|
||
if load_wasm_items {
|
||
info.load_wasm_imports(tcx, LOCAL_CRATE);
|
||
}
|
||
|
||
let crates = tcx.crates();
|
||
|
||
let n_crates = crates.len();
|
||
info.native_libraries.reserve(n_crates);
|
||
info.crate_name.reserve(n_crates);
|
||
info.used_crate_source.reserve(n_crates);
|
||
info.missing_lang_items.reserve(n_crates);
|
||
|
||
for &cnum in crates.iter() {
|
||
info.native_libraries.insert(cnum, tcx.native_libraries(cnum));
|
||
info.crate_name.insert(cnum, tcx.crate_name(cnum).to_string());
|
||
info.used_crate_source.insert(cnum, tcx.used_crate_source(cnum));
|
||
if tcx.is_panic_runtime(cnum) {
|
||
info.panic_runtime = Some(cnum);
|
||
}
|
||
if tcx.is_compiler_builtins(cnum) {
|
||
info.compiler_builtins = Some(cnum);
|
||
}
|
||
if tcx.is_profiler_runtime(cnum) {
|
||
info.profiler_runtime = Some(cnum);
|
||
}
|
||
if tcx.is_sanitizer_runtime(cnum) {
|
||
info.sanitizer_runtime = Some(cnum);
|
||
}
|
||
if tcx.is_no_builtins(cnum) {
|
||
info.is_no_builtins.insert(cnum);
|
||
}
|
||
if load_wasm_items {
|
||
info.load_wasm_imports(tcx, cnum);
|
||
}
|
||
let missing = tcx.missing_lang_items(cnum);
|
||
for &item in missing.iter() {
|
||
if let Ok(id) = lang_items.require(item) {
|
||
info.lang_item_to_crate.insert(item, id.krate);
|
||
}
|
||
}
|
||
|
||
// No need to look for lang items that are whitelisted and don't
|
||
// actually need to exist.
|
||
let missing = missing.iter()
|
||
.cloned()
|
||
.filter(|&l| !weak_lang_items::whitelisted(tcx, l))
|
||
.collect();
|
||
info.missing_lang_items.insert(cnum, missing);
|
||
}
|
||
|
||
return info
|
||
}
|
||
|
||
fn load_wasm_imports(&mut self, tcx: TyCtxt, cnum: CrateNum) {
|
||
self.wasm_imports.extend(tcx.wasm_import_module_map(cnum).iter().map(|(&id, module)| {
|
||
let instance = Instance::mono(tcx, id);
|
||
let import_name = tcx.symbol_name(instance);
|
||
|
||
(import_name.to_string(), module.clone())
|
||
}));
|
||
}
|
||
}
|
||
|
||
fn is_codegened_item(tcx: TyCtxt, id: DefId) -> bool {
|
||
let (all_mono_items, _) =
|
||
tcx.collect_and_partition_mono_items(LOCAL_CRATE);
|
||
all_mono_items.contains(&id)
|
||
}
|
||
|
||
pub fn provide_both(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);
|
||
for id in &*defids {
|
||
let hir::CodegenFnAttrs { optimize, .. } = tcx.codegen_fn_attrs(*id);
|
||
match optimize {
|
||
attr::OptimizeAttr::None => continue,
|
||
attr::OptimizeAttr::Size => continue,
|
||
attr::OptimizeAttr::Speed => {
|
||
return for_speed;
|
||
}
|
||
}
|
||
}
|
||
return tcx.sess.opts.optimize;
|
||
};
|
||
|
||
providers.dllimport_foreign_items = |tcx, krate| {
|
||
let module_map = tcx.foreign_modules(krate);
|
||
let module_map = module_map.iter()
|
||
.map(|lib| (lib.def_id, lib))
|
||
.collect::<FxHashMap<_, _>>();
|
||
|
||
let dllimports = tcx.native_libraries(krate)
|
||
.iter()
|
||
.filter(|lib| {
|
||
if lib.kind != cstore::NativeLibraryKind::NativeUnknown {
|
||
return false
|
||
}
|
||
let cfg = match lib.cfg {
|
||
Some(ref cfg) => cfg,
|
||
None => return true,
|
||
};
|
||
attr::cfg_matches(cfg, &tcx.sess.parse_sess, None)
|
||
})
|
||
.filter_map(|lib| lib.foreign_module)
|
||
.map(|id| &module_map[&id])
|
||
.flat_map(|module| module.foreign_items.iter().cloned())
|
||
.collect();
|
||
Lrc::new(dllimports)
|
||
};
|
||
|
||
providers.is_dllimport_foreign_item = |tcx, def_id| {
|
||
tcx.dllimport_foreign_items(def_id.krate).contains(&def_id)
|
||
};
|
||
}
|
||
|
||
fn determine_cgu_reuse<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, '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.dep_graph.try_mark_green(tcx, &dep_node).is_some() {
|
||
// We can re-use either the pre- or the post-thinlto state
|
||
if tcx.sess.lto() != Lto::No {
|
||
CguReuse::PreLto
|
||
} else {
|
||
CguReuse::PostLto
|
||
}
|
||
} else {
|
||
CguReuse::No
|
||
}
|
||
}
|