diff options
Diffstat (limited to 'compiler/rustc_mir_transform/src')
16 files changed, 275 insertions, 15 deletions
diff --git a/compiler/rustc_mir_transform/src/add_moves_for_packed_drops.rs b/compiler/rustc_mir_transform/src/add_moves_for_packed_drops.rs index 8716fd1c098..b33326cb873 100644 --- a/compiler/rustc_mir_transform/src/add_moves_for_packed_drops.rs +++ b/compiler/rustc_mir_transform/src/add_moves_for_packed_drops.rs @@ -1,8 +1,8 @@ -use rustc_middle::mir::patch::MirPatch; use rustc_middle::mir::*; use rustc_middle::ty::{self, TyCtxt}; use tracing::debug; +use crate::patch::MirPatch; use crate::util; /// This pass moves values being dropped that are within a packed diff --git a/compiler/rustc_mir_transform/src/add_subtyping_projections.rs b/compiler/rustc_mir_transform/src/add_subtyping_projections.rs index e41f47db545..b5cd4133459 100644 --- a/compiler/rustc_mir_transform/src/add_subtyping_projections.rs +++ b/compiler/rustc_mir_transform/src/add_subtyping_projections.rs @@ -1,8 +1,9 @@ -use rustc_middle::mir::patch::MirPatch; use rustc_middle::mir::visit::MutVisitor; use rustc_middle::mir::*; use rustc_middle::ty::TyCtxt; +use crate::patch::MirPatch; + pub(super) struct Subtyper; struct SubTypeChecker<'a, 'tcx> { diff --git a/compiler/rustc_mir_transform/src/coroutine.rs b/compiler/rustc_mir_transform/src/coroutine.rs index ba19a2b5004..afc49c5cc54 100644 --- a/compiler/rustc_mir_transform/src/coroutine.rs +++ b/compiler/rustc_mir_transform/src/coroutine.rs @@ -1061,9 +1061,8 @@ fn insert_switch<'tcx>( } fn elaborate_coroutine_drops<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - use rustc_middle::mir::patch::MirPatch; - use crate::elaborate_drop::{Unwind, elaborate_drop}; + use crate::patch::MirPatch; use crate::shim::DropShimElaborator; // Note that `elaborate_drops` only drops the upvars of a coroutine, and diff --git a/compiler/rustc_mir_transform/src/deref_separator.rs b/compiler/rustc_mir_transform/src/deref_separator.rs index a54bdaa4075..bc914ea6564 100644 --- a/compiler/rustc_mir_transform/src/deref_separator.rs +++ b/compiler/rustc_mir_transform/src/deref_separator.rs @@ -1,9 +1,10 @@ -use rustc_middle::mir::patch::MirPatch; use rustc_middle::mir::visit::NonUseContext::VarDebugInfo; use rustc_middle::mir::visit::{MutVisitor, PlaceContext}; use rustc_middle::mir::*; use rustc_middle::ty::TyCtxt; +use crate::patch::MirPatch; + pub(super) struct Derefer; struct DerefChecker<'a, 'tcx> { diff --git a/compiler/rustc_mir_transform/src/early_otherwise_branch.rs b/compiler/rustc_mir_transform/src/early_otherwise_branch.rs index eb335a1e4a7..57f7893be1b 100644 --- a/compiler/rustc_mir_transform/src/early_otherwise_branch.rs +++ b/compiler/rustc_mir_transform/src/early_otherwise_branch.rs @@ -1,11 +1,11 @@ use std::fmt::Debug; -use rustc_middle::mir::patch::MirPatch; use rustc_middle::mir::*; use rustc_middle::ty::{Ty, TyCtxt}; use tracing::trace; use super::simplify::simplify_cfg; +use crate::patch::MirPatch; /// This pass optimizes something like /// ```ignore (syntax-highlighting-only) diff --git a/compiler/rustc_mir_transform/src/elaborate_box_derefs.rs b/compiler/rustc_mir_transform/src/elaborate_box_derefs.rs index 6d3b5d9851b..5c344a80688 100644 --- a/compiler/rustc_mir_transform/src/elaborate_box_derefs.rs +++ b/compiler/rustc_mir_transform/src/elaborate_box_derefs.rs @@ -4,12 +4,13 @@ use rustc_abi::FieldIdx; use rustc_hir::def_id::DefId; -use rustc_middle::mir::patch::MirPatch; use rustc_middle::mir::visit::MutVisitor; use rustc_middle::mir::*; use rustc_middle::span_bug; use rustc_middle::ty::{Ty, TyCtxt}; +use crate::patch::MirPatch; + /// Constructs the types used when accessing a Box's pointer fn build_ptr_tys<'tcx>( tcx: TyCtxt<'tcx>, diff --git a/compiler/rustc_mir_transform/src/elaborate_drop.rs b/compiler/rustc_mir_transform/src/elaborate_drop.rs index 46eb861e384..ed4903017f3 100644 --- a/compiler/rustc_mir_transform/src/elaborate_drop.rs +++ b/compiler/rustc_mir_transform/src/elaborate_drop.rs @@ -3,7 +3,6 @@ use std::{fmt, iter, mem}; use rustc_abi::{FIRST_VARIANT, FieldIdx, VariantIdx}; use rustc_hir::lang_items::LangItem; use rustc_index::Idx; -use rustc_middle::mir::patch::MirPatch; use rustc_middle::mir::*; use rustc_middle::span_bug; use rustc_middle::ty::adjustment::PointerCoercion; @@ -13,6 +12,8 @@ use rustc_span::DUMMY_SP; use rustc_span::source_map::Spanned; use tracing::{debug, instrument}; +use crate::patch::MirPatch; + /// Describes how/if a value should be dropped. #[derive(Debug)] pub(crate) enum DropStyle { diff --git a/compiler/rustc_mir_transform/src/elaborate_drops.rs b/compiler/rustc_mir_transform/src/elaborate_drops.rs index ff426626249..2d74fcff415 100644 --- a/compiler/rustc_mir_transform/src/elaborate_drops.rs +++ b/compiler/rustc_mir_transform/src/elaborate_drops.rs @@ -3,7 +3,6 @@ use std::fmt; use rustc_abi::{FieldIdx, VariantIdx}; use rustc_index::IndexVec; use rustc_index::bit_set::DenseBitSet; -use rustc_middle::mir::patch::MirPatch; use rustc_middle::mir::*; use rustc_middle::ty::{self, TyCtxt}; use rustc_mir_dataflow::impls::{MaybeInitializedPlaces, MaybeUninitializedPlaces}; @@ -17,6 +16,7 @@ use tracing::{debug, instrument}; use crate::deref_separator::deref_finder; use crate::elaborate_drop::{DropElaborator, DropFlagMode, DropStyle, Unwind, elaborate_drop}; +use crate::patch::MirPatch; /// During MIR building, Drop terminators are inserted in every place where a drop may occur. /// However, in this phase, the presence of these terminators does not guarantee that a destructor diff --git a/compiler/rustc_mir_transform/src/lib.rs b/compiler/rustc_mir_transform/src/lib.rs index b7c72866fba..46abdcb2a87 100644 --- a/compiler/rustc_mir_transform/src/lib.rs +++ b/compiler/rustc_mir_transform/src/lib.rs @@ -54,6 +54,7 @@ mod errors; mod ffi_unwind_calls; mod lint; mod lint_tail_expr_drop_order; +mod patch; mod shim; mod ssa; diff --git a/compiler/rustc_mir_transform/src/match_branches.rs b/compiler/rustc_mir_transform/src/match_branches.rs index 500116580d5..9db37bf5a07 100644 --- a/compiler/rustc_mir_transform/src/match_branches.rs +++ b/compiler/rustc_mir_transform/src/match_branches.rs @@ -2,7 +2,6 @@ use std::iter; use rustc_abi::Integer; use rustc_index::IndexSlice; -use rustc_middle::mir::patch::MirPatch; use rustc_middle::mir::*; use rustc_middle::ty::layout::{IntegerExt, TyAndLayout}; use rustc_middle::ty::{self, ScalarInt, Ty, TyCtxt}; @@ -10,6 +9,7 @@ use rustc_type_ir::TyKind::*; use tracing::instrument; use super::simplify::simplify_cfg; +use crate::patch::MirPatch; pub(super) struct MatchBranchSimplification; diff --git a/compiler/rustc_mir_transform/src/patch.rs b/compiler/rustc_mir_transform/src/patch.rs new file mode 100644 index 00000000000..72cd9c224f6 --- /dev/null +++ b/compiler/rustc_mir_transform/src/patch.rs @@ -0,0 +1,252 @@ +use rustc_index::{Idx, IndexVec}; +use rustc_middle::mir::*; +use rustc_middle::ty::Ty; +use rustc_span::Span; +use tracing::debug; + +/// This struct represents a patch to MIR, which can add +/// new statements and basic blocks and patch over block +/// terminators. +pub(crate) struct MirPatch<'tcx> { + patch_map: IndexVec<BasicBlock, Option<TerminatorKind<'tcx>>>, + new_blocks: Vec<BasicBlockData<'tcx>>, + new_statements: Vec<(Location, StatementKind<'tcx>)>, + new_locals: Vec<LocalDecl<'tcx>>, + resume_block: Option<BasicBlock>, + // Only for unreachable in cleanup path. + unreachable_cleanup_block: Option<BasicBlock>, + // Only for unreachable not in cleanup path. + unreachable_no_cleanup_block: Option<BasicBlock>, + // Cached block for UnwindTerminate (with reason) + terminate_block: Option<(BasicBlock, UnwindTerminateReason)>, + body_span: Span, + next_local: usize, +} + +impl<'tcx> MirPatch<'tcx> { + pub(crate) fn new(body: &Body<'tcx>) -> Self { + let mut result = MirPatch { + patch_map: IndexVec::from_elem(None, &body.basic_blocks), + new_blocks: vec![], + new_statements: vec![], + new_locals: vec![], + next_local: body.local_decls.len(), + resume_block: None, + unreachable_cleanup_block: None, + unreachable_no_cleanup_block: None, + terminate_block: None, + body_span: body.span, + }; + + for (bb, block) in body.basic_blocks.iter_enumerated() { + // Check if we already have a resume block + if matches!(block.terminator().kind, TerminatorKind::UnwindResume) + && block.statements.is_empty() + { + result.resume_block = Some(bb); + continue; + } + + // Check if we already have an unreachable block + if matches!(block.terminator().kind, TerminatorKind::Unreachable) + && block.statements.is_empty() + { + if block.is_cleanup { + result.unreachable_cleanup_block = Some(bb); + } else { + result.unreachable_no_cleanup_block = Some(bb); + } + continue; + } + + // Check if we already have a terminate block + if let TerminatorKind::UnwindTerminate(reason) = block.terminator().kind + && block.statements.is_empty() + { + result.terminate_block = Some((bb, reason)); + continue; + } + } + + result + } + + pub(crate) fn resume_block(&mut self) -> BasicBlock { + if let Some(bb) = self.resume_block { + return bb; + } + + let bb = self.new_block(BasicBlockData { + statements: vec![], + terminator: Some(Terminator { + source_info: SourceInfo::outermost(self.body_span), + kind: TerminatorKind::UnwindResume, + }), + is_cleanup: true, + }); + self.resume_block = Some(bb); + bb + } + + pub(crate) fn unreachable_cleanup_block(&mut self) -> BasicBlock { + if let Some(bb) = self.unreachable_cleanup_block { + return bb; + } + + let bb = self.new_block(BasicBlockData { + statements: vec![], + terminator: Some(Terminator { + source_info: SourceInfo::outermost(self.body_span), + kind: TerminatorKind::Unreachable, + }), + is_cleanup: true, + }); + self.unreachable_cleanup_block = Some(bb); + bb + } + + pub(crate) fn unreachable_no_cleanup_block(&mut self) -> BasicBlock { + if let Some(bb) = self.unreachable_no_cleanup_block { + return bb; + } + + let bb = self.new_block(BasicBlockData { + statements: vec![], + terminator: Some(Terminator { + source_info: SourceInfo::outermost(self.body_span), + kind: TerminatorKind::Unreachable, + }), + is_cleanup: false, + }); + self.unreachable_no_cleanup_block = Some(bb); + bb + } + + pub(crate) fn terminate_block(&mut self, reason: UnwindTerminateReason) -> BasicBlock { + if let Some((cached_bb, cached_reason)) = self.terminate_block + && reason == cached_reason + { + return cached_bb; + } + + let bb = self.new_block(BasicBlockData { + statements: vec![], + terminator: Some(Terminator { + source_info: SourceInfo::outermost(self.body_span), + kind: TerminatorKind::UnwindTerminate(reason), + }), + is_cleanup: true, + }); + self.terminate_block = Some((bb, reason)); + bb + } + + pub(crate) fn is_patched(&self, bb: BasicBlock) -> bool { + self.patch_map[bb].is_some() + } + + pub(crate) fn new_local_with_info( + &mut self, + ty: Ty<'tcx>, + span: Span, + local_info: LocalInfo<'tcx>, + ) -> Local { + let index = self.next_local; + self.next_local += 1; + let mut new_decl = LocalDecl::new(ty, span); + **new_decl.local_info.as_mut().assert_crate_local() = local_info; + self.new_locals.push(new_decl); + Local::new(index) + } + + pub(crate) fn new_temp(&mut self, ty: Ty<'tcx>, span: Span) -> Local { + let index = self.next_local; + self.next_local += 1; + self.new_locals.push(LocalDecl::new(ty, span)); + Local::new(index) + } + + pub(crate) fn new_block(&mut self, data: BasicBlockData<'tcx>) -> BasicBlock { + let block = BasicBlock::new(self.patch_map.len()); + debug!("MirPatch: new_block: {:?}: {:?}", block, data); + self.new_blocks.push(data); + self.patch_map.push(None); + block + } + + pub(crate) fn patch_terminator(&mut self, block: BasicBlock, new: TerminatorKind<'tcx>) { + assert!(self.patch_map[block].is_none()); + debug!("MirPatch: patch_terminator({:?}, {:?})", block, new); + self.patch_map[block] = Some(new); + } + + pub(crate) fn add_statement(&mut self, loc: Location, stmt: StatementKind<'tcx>) { + debug!("MirPatch: add_statement({:?}, {:?})", loc, stmt); + self.new_statements.push((loc, stmt)); + } + + pub(crate) fn add_assign(&mut self, loc: Location, place: Place<'tcx>, rv: Rvalue<'tcx>) { + self.add_statement(loc, StatementKind::Assign(Box::new((place, rv)))); + } + + pub(crate) fn apply(self, body: &mut Body<'tcx>) { + debug!( + "MirPatch: {:?} new temps, starting from index {}: {:?}", + self.new_locals.len(), + body.local_decls.len(), + self.new_locals + ); + debug!( + "MirPatch: {} new blocks, starting from index {}", + self.new_blocks.len(), + body.basic_blocks.len() + ); + let bbs = if self.patch_map.is_empty() && self.new_blocks.is_empty() { + body.basic_blocks.as_mut_preserves_cfg() + } else { + body.basic_blocks.as_mut() + }; + bbs.extend(self.new_blocks); + body.local_decls.extend(self.new_locals); + for (src, patch) in self.patch_map.into_iter_enumerated() { + if let Some(patch) = patch { + debug!("MirPatch: patching block {:?}", src); + bbs[src].terminator_mut().kind = patch; + } + } + + let mut new_statements = self.new_statements; + new_statements.sort_by_key(|s| s.0); + + let mut delta = 0; + let mut last_bb = START_BLOCK; + for (mut loc, stmt) in new_statements { + if loc.block != last_bb { + delta = 0; + last_bb = loc.block; + } + debug!("MirPatch: adding statement {:?} at loc {:?}+{}", stmt, loc, delta); + loc.statement_index += delta; + let source_info = Self::source_info_for_index(&body[loc.block], loc); + body[loc.block] + .statements + .insert(loc.statement_index, Statement { source_info, kind: stmt }); + delta += 1; + } + } + + fn source_info_for_index(data: &BasicBlockData<'_>, loc: Location) -> SourceInfo { + match data.statements.get(loc.statement_index) { + Some(stmt) => stmt.source_info, + None => data.terminator().source_info, + } + } + + pub(crate) fn source_info_for_location(&self, body: &Body<'tcx>, loc: Location) -> SourceInfo { + let data = match loc.block.index().checked_sub(body.basic_blocks.len()) { + Some(new) => &self.new_blocks[new], + None => &body[loc.block], + }; + Self::source_info_for_index(data, loc) + } +} diff --git a/compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs b/compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs index 9cdd52bec7b..1dd34005d66 100644 --- a/compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs +++ b/compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs @@ -1,10 +1,11 @@ use rustc_index::bit_set::DenseBitSet; -use rustc_middle::mir::patch::MirPatch; use rustc_middle::mir::*; use rustc_middle::ty::TyCtxt; use rustc_target::spec::PanicStrategy; use tracing::debug; +use crate::patch::MirPatch; + /// A pass that removes noop landing pads and replaces jumps to them with /// `UnwindAction::Continue`. This is important because otherwise LLVM generates /// terrible code for these. diff --git a/compiler/rustc_mir_transform/src/shim.rs b/compiler/rustc_mir_transform/src/shim.rs index 06f154e65b3..e8d86bad987 100644 --- a/compiler/rustc_mir_transform/src/shim.rs +++ b/compiler/rustc_mir_transform/src/shim.rs @@ -6,7 +6,6 @@ use rustc_hir as hir; use rustc_hir::def_id::DefId; use rustc_hir::lang_items::LangItem; use rustc_index::{Idx, IndexVec}; -use rustc_middle::mir::patch::MirPatch; use rustc_middle::mir::*; use rustc_middle::query::Providers; use rustc_middle::ty::adjustment::PointerCoercion; @@ -19,6 +18,7 @@ use rustc_span::{DUMMY_SP, Span}; use tracing::{debug, instrument}; use crate::elaborate_drop::{DropElaborator, DropFlagMode, DropStyle, Unwind, elaborate_drop}; +use crate::patch::MirPatch; use crate::{ abort_unwinding_calls, add_call_guards, add_moves_for_packed_drops, deref_separator, inline, instsimplify, mentioned_items, pass_manager as pm, remove_noop_landing_pads, simplify, diff --git a/compiler/rustc_mir_transform/src/sroa.rs b/compiler/rustc_mir_transform/src/sroa.rs index 92e5c8a9ca4..28de99f9193 100644 --- a/compiler/rustc_mir_transform/src/sroa.rs +++ b/compiler/rustc_mir_transform/src/sroa.rs @@ -4,13 +4,14 @@ use rustc_hir::LangItem; use rustc_index::IndexVec; use rustc_index::bit_set::{DenseBitSet, GrowableBitSet}; use rustc_middle::bug; -use rustc_middle::mir::patch::MirPatch; use rustc_middle::mir::visit::*; use rustc_middle::mir::*; use rustc_middle::ty::{self, Ty, TyCtxt}; use rustc_mir_dataflow::value_analysis::{excluded_locals, iter_fields}; use tracing::{debug, instrument}; +use crate::patch::MirPatch; + pub(super) struct ScalarReplacementOfAggregates; impl<'tcx> crate::MirPass<'tcx> for ScalarReplacementOfAggregates { diff --git a/compiler/rustc_mir_transform/src/unreachable_enum_branching.rs b/compiler/rustc_mir_transform/src/unreachable_enum_branching.rs index 1ff7043ed14..6ccec5b6f21 100644 --- a/compiler/rustc_mir_transform/src/unreachable_enum_branching.rs +++ b/compiler/rustc_mir_transform/src/unreachable_enum_branching.rs @@ -3,7 +3,6 @@ use rustc_abi::Variants; use rustc_data_structures::fx::FxHashSet; use rustc_middle::bug; -use rustc_middle::mir::patch::MirPatch; use rustc_middle::mir::{ BasicBlock, BasicBlockData, BasicBlocks, Body, Local, Operand, Rvalue, StatementKind, TerminatorKind, @@ -12,6 +11,8 @@ use rustc_middle::ty::layout::TyAndLayout; use rustc_middle::ty::{Ty, TyCtxt}; use tracing::trace; +use crate::patch::MirPatch; + pub(super) struct UnreachableEnumBranching; fn get_discriminant_local(terminator: &TerminatorKind<'_>) -> Option<Local> { diff --git a/compiler/rustc_mir_transform/src/unreachable_prop.rs b/compiler/rustc_mir_transform/src/unreachable_prop.rs index 1e5d9469c03..13fb5b3e56f 100644 --- a/compiler/rustc_mir_transform/src/unreachable_prop.rs +++ b/compiler/rustc_mir_transform/src/unreachable_prop.rs @@ -6,10 +6,11 @@ use rustc_abi::Size; use rustc_data_structures::fx::FxHashSet; use rustc_middle::bug; use rustc_middle::mir::interpret::Scalar; -use rustc_middle::mir::patch::MirPatch; use rustc_middle::mir::*; use rustc_middle::ty::{self, TyCtxt}; +use crate::patch::MirPatch; + pub(super) struct UnreachablePropagation; impl crate::MirPass<'_> for UnreachablePropagation { |