diff options
| author | Nicholas Nethercote <n.nethercote@gmail.com> | 2024-08-28 10:13:17 +1000 |
|---|---|---|
| committer | Nicholas Nethercote <n.nethercote@gmail.com> | 2024-09-10 08:54:17 +1000 |
| commit | 48064d44982d505412d9328004ed5cc67cb5f210 (patch) | |
| tree | 25c76b17ff77228c1eb46b2c0573090bc11c4939 /compiler/rustc_mir_transform/src | |
| parent | 8235af07d21d60012acbd217f24049e1386081bd (diff) | |
| download | rust-48064d44982d505412d9328004ed5cc67cb5f210.tar.gz rust-48064d44982d505412d9328004ed5cc67cb5f210.zip | |
Inline and remove some functions.
These are all functions with a single callsite, where having a separate function does nothing to help with readability. These changes make the code a little shorter and easier to read.
Diffstat (limited to 'compiler/rustc_mir_transform/src')
| -rw-r--r-- | compiler/rustc_mir_transform/src/add_call_guards.rs | 6 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/add_moves_for_packed_drops.rs | 45 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/add_subtyping_projections.rs | 18 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/copy_prop.rs | 45 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/gvn.rs | 85 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/instsimplify.rs | 8 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/large_enums.rs | 345 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/lower_slice_len.rs | 26 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs | 113 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/simplify.rs | 48 |
10 files changed, 344 insertions, 395 deletions
diff --git a/compiler/rustc_mir_transform/src/add_call_guards.rs b/compiler/rustc_mir_transform/src/add_call_guards.rs index 18a0746f54f..24c955c0c78 100644 --- a/compiler/rustc_mir_transform/src/add_call_guards.rs +++ b/compiler/rustc_mir_transform/src/add_call_guards.rs @@ -32,12 +32,6 @@ pub(super) use self::AddCallGuards::*; impl<'tcx> crate::MirPass<'tcx> for AddCallGuards { fn run_pass(&self, _tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - self.add_call_guards(body); - } -} - -impl AddCallGuards { - pub(super) fn add_call_guards(&self, body: &mut Body<'_>) { let mut pred_count: IndexVec<_, _> = body.basic_blocks.predecessors().iter().map(|ps| ps.len()).collect(); pred_count[START_BLOCK] += 1; 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 47572d8d3b2..74df5f7479e 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 @@ -40,35 +40,34 @@ pub(super) struct AddMovesForPackedDrops; impl<'tcx> crate::MirPass<'tcx> for AddMovesForPackedDrops { fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { debug!("add_moves_for_packed_drops({:?} @ {:?})", body.source, body.span); - add_moves_for_packed_drops(tcx, body); - } -} - -fn add_moves_for_packed_drops<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - let patch = add_moves_for_packed_drops_patch(tcx, body); - patch.apply(body); -} -fn add_moves_for_packed_drops_patch<'tcx>(tcx: TyCtxt<'tcx>, body: &Body<'tcx>) -> MirPatch<'tcx> { - let def_id = body.source.def_id(); - let mut patch = MirPatch::new(body); - let param_env = tcx.param_env(def_id); + let def_id = body.source.def_id(); + let mut patch = MirPatch::new(body); + let param_env = tcx.param_env(def_id); - for (bb, data) in body.basic_blocks.iter_enumerated() { - let loc = Location { block: bb, statement_index: data.statements.len() }; - let terminator = data.terminator(); + for (bb, data) in body.basic_blocks.iter_enumerated() { + let loc = Location { block: bb, statement_index: data.statements.len() }; + let terminator = data.terminator(); - match terminator.kind { - TerminatorKind::Drop { place, .. } - if util::is_disaligned(tcx, body, param_env, place) => - { - add_move_for_packed_drop(tcx, body, &mut patch, terminator, loc, data.is_cleanup); + match terminator.kind { + TerminatorKind::Drop { place, .. } + if util::is_disaligned(tcx, body, param_env, place) => + { + add_move_for_packed_drop( + tcx, + body, + &mut patch, + terminator, + loc, + data.is_cleanup, + ); + } + _ => {} } - _ => {} } - } - patch + patch.apply(body); + } } fn add_move_for_packed_drop<'tcx>( diff --git a/compiler/rustc_mir_transform/src/add_subtyping_projections.rs b/compiler/rustc_mir_transform/src/add_subtyping_projections.rs index ab6bf18b30c..e585e338613 100644 --- a/compiler/rustc_mir_transform/src/add_subtyping_projections.rs +++ b/compiler/rustc_mir_transform/src/add_subtyping_projections.rs @@ -51,18 +51,14 @@ impl<'a, 'tcx> MutVisitor<'tcx> for SubTypeChecker<'a, 'tcx> { // // gets transformed to // let temp: rval_ty = rval; // let place: place_ty = temp as place_ty; -fn subtype_finder<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - let patch = MirPatch::new(body); - let mut checker = SubTypeChecker { tcx, patcher: patch, local_decls: &body.local_decls }; - - for (bb, data) in body.basic_blocks.as_mut_preserves_cfg().iter_enumerated_mut() { - checker.visit_basic_block_data(bb, data); - } - checker.patcher.apply(body); -} - impl<'tcx> crate::MirPass<'tcx> for Subtyper { fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - subtype_finder(tcx, body); + let patch = MirPatch::new(body); + let mut checker = SubTypeChecker { tcx, patcher: patch, local_decls: &body.local_decls }; + + for (bb, data) in body.basic_blocks.as_mut_preserves_cfg().iter_enumerated_mut() { + checker.visit_basic_block_data(bb, data); + } + checker.patcher.apply(body); } } diff --git a/compiler/rustc_mir_transform/src/copy_prop.rs b/compiler/rustc_mir_transform/src/copy_prop.rs index 1cb56d29b85..b3db5669121 100644 --- a/compiler/rustc_mir_transform/src/copy_prop.rs +++ b/compiler/rustc_mir_transform/src/copy_prop.rs @@ -27,37 +27,34 @@ impl<'tcx> crate::MirPass<'tcx> for CopyProp { #[instrument(level = "trace", skip(self, tcx, body))] fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { debug!(def_id = ?body.source.def_id()); - propagate_ssa(tcx, body); - } -} -fn propagate_ssa<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id()); - let ssa = SsaLocals::new(tcx, body, param_env); + let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id()); + let ssa = SsaLocals::new(tcx, body, param_env); - let fully_moved = fully_moved_locals(&ssa, body); - debug!(?fully_moved); + let fully_moved = fully_moved_locals(&ssa, body); + debug!(?fully_moved); - let mut storage_to_remove = BitSet::new_empty(fully_moved.domain_size()); - for (local, &head) in ssa.copy_classes().iter_enumerated() { - if local != head { - storage_to_remove.insert(head); + let mut storage_to_remove = BitSet::new_empty(fully_moved.domain_size()); + for (local, &head) in ssa.copy_classes().iter_enumerated() { + if local != head { + storage_to_remove.insert(head); + } } - } - let any_replacement = ssa.copy_classes().iter_enumerated().any(|(l, &h)| l != h); + let any_replacement = ssa.copy_classes().iter_enumerated().any(|(l, &h)| l != h); - Replacer { - tcx, - copy_classes: ssa.copy_classes(), - fully_moved, - borrowed_locals: ssa.borrowed_locals(), - storage_to_remove, - } - .visit_body_preserves_cfg(body); + Replacer { + tcx, + copy_classes: ssa.copy_classes(), + fully_moved, + borrowed_locals: ssa.borrowed_locals(), + storage_to_remove, + } + .visit_body_preserves_cfg(body); - if any_replacement { - crate::simplify::remove_unused_definitions(body); + if any_replacement { + crate::simplify::remove_unused_definitions(body); + } } } diff --git a/compiler/rustc_mir_transform/src/gvn.rs b/compiler/rustc_mir_transform/src/gvn.rs index 715461de064..d514664f368 100644 --- a/compiler/rustc_mir_transform/src/gvn.rs +++ b/compiler/rustc_mir_transform/src/gvn.rs @@ -119,53 +119,50 @@ impl<'tcx> crate::MirPass<'tcx> for GVN { #[instrument(level = "trace", skip(self, tcx, body))] fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { debug!(def_id = ?body.source.def_id()); - propagate_ssa(tcx, body); - } -} -fn propagate_ssa<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id()); - let ssa = SsaLocals::new(tcx, body, param_env); - // Clone dominators as we need them while mutating the body. - let dominators = body.basic_blocks.dominators().clone(); - - let mut state = VnState::new(tcx, body, param_env, &ssa, &dominators, &body.local_decls); - ssa.for_each_assignment_mut( - body.basic_blocks.as_mut_preserves_cfg(), - |local, value, location| { - let value = match value { - // We do not know anything of this assigned value. - AssignedValue::Arg | AssignedValue::Terminator => None, - // Try to get some insight. - AssignedValue::Rvalue(rvalue) => { - let value = state.simplify_rvalue(rvalue, location); - // FIXME(#112651) `rvalue` may have a subtype to `local`. We can only mark - // `local` as reusable if we have an exact type match. - if state.local_decls[local].ty != rvalue.ty(state.local_decls, tcx) { - return; + let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id()); + let ssa = SsaLocals::new(tcx, body, param_env); + // Clone dominators as we need them while mutating the body. + let dominators = body.basic_blocks.dominators().clone(); + + let mut state = VnState::new(tcx, body, param_env, &ssa, &dominators, &body.local_decls); + ssa.for_each_assignment_mut( + body.basic_blocks.as_mut_preserves_cfg(), + |local, value, location| { + let value = match value { + // We do not know anything of this assigned value. + AssignedValue::Arg | AssignedValue::Terminator => None, + // Try to get some insight. + AssignedValue::Rvalue(rvalue) => { + let value = state.simplify_rvalue(rvalue, location); + // FIXME(#112651) `rvalue` may have a subtype to `local`. We can only mark + // `local` as reusable if we have an exact type match. + if state.local_decls[local].ty != rvalue.ty(state.local_decls, tcx) { + return; + } + value } - value - } - }; - // `next_opaque` is `Some`, so `new_opaque` must return `Some`. - let value = value.or_else(|| state.new_opaque()).unwrap(); - state.assign(local, value); - }, - ); - - // Stop creating opaques during replacement as it is useless. - state.next_opaque = None; - - let reverse_postorder = body.basic_blocks.reverse_postorder().to_vec(); - for bb in reverse_postorder { - let data = &mut body.basic_blocks.as_mut_preserves_cfg()[bb]; - state.visit_basic_block_data(bb, data); - } + }; + // `next_opaque` is `Some`, so `new_opaque` must return `Some`. + let value = value.or_else(|| state.new_opaque()).unwrap(); + state.assign(local, value); + }, + ); + + // Stop creating opaques during replacement as it is useless. + state.next_opaque = None; - // For each local that is reused (`y` above), we remove its storage statements do avoid any - // difficulty. Those locals are SSA, so should be easy to optimize by LLVM without storage - // statements. - StorageRemover { tcx, reused_locals: state.reused_locals }.visit_body_preserves_cfg(body); + let reverse_postorder = body.basic_blocks.reverse_postorder().to_vec(); + for bb in reverse_postorder { + let data = &mut body.basic_blocks.as_mut_preserves_cfg()[bb]; + state.visit_basic_block_data(bb, data); + } + + // For each local that is reused (`y` above), we remove its storage statements do avoid any + // difficulty. Those locals are SSA, so should be easy to optimize by LLVM without storage + // statements. + StorageRemover { tcx, reused_locals: state.reused_locals }.visit_body_preserves_cfg(body); + } } newtype_index! { diff --git a/compiler/rustc_mir_transform/src/instsimplify.rs b/compiler/rustc_mir_transform/src/instsimplify.rs index a9591bf3984..0b344f29b07 100644 --- a/compiler/rustc_mir_transform/src/instsimplify.rs +++ b/compiler/rustc_mir_transform/src/instsimplify.rs @@ -18,19 +18,13 @@ pub(super) enum InstSimplify { AfterSimplifyCfg, } -impl InstSimplify { +impl<'tcx> crate::MirPass<'tcx> for InstSimplify { fn name(&self) -> &'static str { match self { InstSimplify::BeforeInline => "InstSimplify-before-inline", InstSimplify::AfterSimplifyCfg => "InstSimplify-after-simplifycfg", } } -} - -impl<'tcx> crate::MirPass<'tcx> for InstSimplify { - fn name(&self) -> &'static str { - self.name() - } fn is_enabled(&self, sess: &rustc_session::Session) -> bool { sess.mir_opt_level() > 0 diff --git a/compiler/rustc_mir_transform/src/large_enums.rs b/compiler/rustc_mir_transform/src/large_enums.rs index 45edcff29eb..8a33849f20e 100644 --- a/compiler/rustc_mir_transform/src/large_enums.rs +++ b/compiler/rustc_mir_transform/src/large_enums.rs @@ -37,7 +37,169 @@ impl<'tcx> crate::MirPass<'tcx> for EnumSizeOpt { fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { // NOTE: This pass may produce different MIR based on the alignment of the target // platform, but it will still be valid. - self.optim(tcx, body); + + let mut alloc_cache = FxHashMap::default(); + let body_did = body.source.def_id(); + let param_env = tcx.param_env_reveal_all_normalized(body_did); + + let blocks = body.basic_blocks.as_mut(); + let local_decls = &mut body.local_decls; + + for bb in blocks { + bb.expand_statements(|st| { + let StatementKind::Assign(box ( + lhs, + Rvalue::Use(Operand::Copy(rhs) | Operand::Move(rhs)), + )) = &st.kind + else { + return None; + }; + + let ty = lhs.ty(local_decls, tcx).ty; + + let (adt_def, num_variants, alloc_id) = + self.candidate(tcx, param_env, ty, &mut alloc_cache)?; + + let source_info = st.source_info; + let span = source_info.span; + + let tmp_ty = Ty::new_array(tcx, tcx.types.usize, num_variants as u64); + let size_array_local = local_decls.push(LocalDecl::new(tmp_ty, span)); + let store_live = + Statement { source_info, kind: StatementKind::StorageLive(size_array_local) }; + + let place = Place::from(size_array_local); + let constant_vals = ConstOperand { + span, + user_ty: None, + const_: Const::Val( + ConstValue::Indirect { alloc_id, offset: Size::ZERO }, + tmp_ty, + ), + }; + let rval = Rvalue::Use(Operand::Constant(Box::new(constant_vals))); + let const_assign = + Statement { source_info, kind: StatementKind::Assign(Box::new((place, rval))) }; + + let discr_place = Place::from( + local_decls.push(LocalDecl::new(adt_def.repr().discr_type().to_ty(tcx), span)), + ); + let store_discr = Statement { + source_info, + kind: StatementKind::Assign(Box::new(( + discr_place, + Rvalue::Discriminant(*rhs), + ))), + }; + + let discr_cast_place = + Place::from(local_decls.push(LocalDecl::new(tcx.types.usize, span))); + let cast_discr = Statement { + source_info, + kind: StatementKind::Assign(Box::new(( + discr_cast_place, + Rvalue::Cast( + CastKind::IntToInt, + Operand::Copy(discr_place), + tcx.types.usize, + ), + ))), + }; + + let size_place = + Place::from(local_decls.push(LocalDecl::new(tcx.types.usize, span))); + let store_size = Statement { + source_info, + kind: StatementKind::Assign(Box::new(( + size_place, + Rvalue::Use(Operand::Copy(Place { + local: size_array_local, + projection: tcx + .mk_place_elems(&[PlaceElem::Index(discr_cast_place.local)]), + })), + ))), + }; + + let dst = + Place::from(local_decls.push(LocalDecl::new(Ty::new_mut_ptr(tcx, ty), span))); + let dst_ptr = Statement { + source_info, + kind: StatementKind::Assign(Box::new(( + dst, + Rvalue::RawPtr(Mutability::Mut, *lhs), + ))), + }; + + let dst_cast_ty = Ty::new_mut_ptr(tcx, tcx.types.u8); + let dst_cast_place = + Place::from(local_decls.push(LocalDecl::new(dst_cast_ty, span))); + let dst_cast = Statement { + source_info, + kind: StatementKind::Assign(Box::new(( + dst_cast_place, + Rvalue::Cast(CastKind::PtrToPtr, Operand::Copy(dst), dst_cast_ty), + ))), + }; + + let src = + Place::from(local_decls.push(LocalDecl::new(Ty::new_imm_ptr(tcx, ty), span))); + let src_ptr = Statement { + source_info, + kind: StatementKind::Assign(Box::new(( + src, + Rvalue::RawPtr(Mutability::Not, *rhs), + ))), + }; + + let src_cast_ty = Ty::new_imm_ptr(tcx, tcx.types.u8); + let src_cast_place = + Place::from(local_decls.push(LocalDecl::new(src_cast_ty, span))); + let src_cast = Statement { + source_info, + kind: StatementKind::Assign(Box::new(( + src_cast_place, + Rvalue::Cast(CastKind::PtrToPtr, Operand::Copy(src), src_cast_ty), + ))), + }; + + let deinit_old = + Statement { source_info, kind: StatementKind::Deinit(Box::new(dst)) }; + + let copy_bytes = Statement { + source_info, + kind: StatementKind::Intrinsic(Box::new( + NonDivergingIntrinsic::CopyNonOverlapping(CopyNonOverlapping { + src: Operand::Copy(src_cast_place), + dst: Operand::Copy(dst_cast_place), + count: Operand::Copy(size_place), + }), + )), + }; + + let store_dead = + Statement { source_info, kind: StatementKind::StorageDead(size_array_local) }; + + let iter = [ + store_live, + const_assign, + store_discr, + cast_discr, + store_size, + dst_ptr, + dst_cast, + src_ptr, + src_cast, + deinit_old, + copy_bytes, + store_dead, + ] + .into_iter(); + + st.make_nop(); + + Some(iter) + }); + } } } @@ -116,185 +278,4 @@ impl EnumSizeOpt { let alloc = tcx.reserve_and_set_memory_alloc(tcx.mk_const_alloc(alloc)); Some((*adt_def, num_discrs, *alloc_cache.entry(ty).or_insert(alloc))) } - - fn optim<'tcx>(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - let mut alloc_cache = FxHashMap::default(); - let body_did = body.source.def_id(); - let param_env = tcx.param_env_reveal_all_normalized(body_did); - - let blocks = body.basic_blocks.as_mut(); - let local_decls = &mut body.local_decls; - - for bb in blocks { - bb.expand_statements(|st| { - if let StatementKind::Assign(box ( - lhs, - Rvalue::Use(Operand::Copy(rhs) | Operand::Move(rhs)), - )) = &st.kind - { - let ty = lhs.ty(local_decls, tcx).ty; - - let source_info = st.source_info; - let span = source_info.span; - - let (adt_def, num_variants, alloc_id) = - self.candidate(tcx, param_env, ty, &mut alloc_cache)?; - - let tmp_ty = Ty::new_array(tcx, tcx.types.usize, num_variants as u64); - - let size_array_local = local_decls.push(LocalDecl::new(tmp_ty, span)); - let store_live = Statement { - source_info, - kind: StatementKind::StorageLive(size_array_local), - }; - - let place = Place::from(size_array_local); - let constant_vals = ConstOperand { - span, - user_ty: None, - const_: Const::Val( - ConstValue::Indirect { alloc_id, offset: Size::ZERO }, - tmp_ty, - ), - }; - let rval = Rvalue::Use(Operand::Constant(Box::new(constant_vals))); - - let const_assign = Statement { - source_info, - kind: StatementKind::Assign(Box::new((place, rval))), - }; - - let discr_place = Place::from( - local_decls - .push(LocalDecl::new(adt_def.repr().discr_type().to_ty(tcx), span)), - ); - - let store_discr = Statement { - source_info, - kind: StatementKind::Assign(Box::new(( - discr_place, - Rvalue::Discriminant(*rhs), - ))), - }; - - let discr_cast_place = - Place::from(local_decls.push(LocalDecl::new(tcx.types.usize, span))); - - let cast_discr = Statement { - source_info, - kind: StatementKind::Assign(Box::new(( - discr_cast_place, - Rvalue::Cast( - CastKind::IntToInt, - Operand::Copy(discr_place), - tcx.types.usize, - ), - ))), - }; - - let size_place = - Place::from(local_decls.push(LocalDecl::new(tcx.types.usize, span))); - - let store_size = Statement { - source_info, - kind: StatementKind::Assign(Box::new(( - size_place, - Rvalue::Use(Operand::Copy(Place { - local: size_array_local, - projection: tcx - .mk_place_elems(&[PlaceElem::Index(discr_cast_place.local)]), - })), - ))), - }; - - let dst = Place::from( - local_decls.push(LocalDecl::new(Ty::new_mut_ptr(tcx, ty), span)), - ); - - let dst_ptr = Statement { - source_info, - kind: StatementKind::Assign(Box::new(( - dst, - Rvalue::RawPtr(Mutability::Mut, *lhs), - ))), - }; - - let dst_cast_ty = Ty::new_mut_ptr(tcx, tcx.types.u8); - let dst_cast_place = - Place::from(local_decls.push(LocalDecl::new(dst_cast_ty, span))); - - let dst_cast = Statement { - source_info, - kind: StatementKind::Assign(Box::new(( - dst_cast_place, - Rvalue::Cast(CastKind::PtrToPtr, Operand::Copy(dst), dst_cast_ty), - ))), - }; - - let src = Place::from( - local_decls.push(LocalDecl::new(Ty::new_imm_ptr(tcx, ty), span)), - ); - - let src_ptr = Statement { - source_info, - kind: StatementKind::Assign(Box::new(( - src, - Rvalue::RawPtr(Mutability::Not, *rhs), - ))), - }; - - let src_cast_ty = Ty::new_imm_ptr(tcx, tcx.types.u8); - let src_cast_place = - Place::from(local_decls.push(LocalDecl::new(src_cast_ty, span))); - - let src_cast = Statement { - source_info, - kind: StatementKind::Assign(Box::new(( - src_cast_place, - Rvalue::Cast(CastKind::PtrToPtr, Operand::Copy(src), src_cast_ty), - ))), - }; - - let deinit_old = - Statement { source_info, kind: StatementKind::Deinit(Box::new(dst)) }; - - let copy_bytes = Statement { - source_info, - kind: StatementKind::Intrinsic(Box::new( - NonDivergingIntrinsic::CopyNonOverlapping(CopyNonOverlapping { - src: Operand::Copy(src_cast_place), - dst: Operand::Copy(dst_cast_place), - count: Operand::Copy(size_place), - }), - )), - }; - - let store_dead = Statement { - source_info, - kind: StatementKind::StorageDead(size_array_local), - }; - let iter = [ - store_live, - const_assign, - store_discr, - cast_discr, - store_size, - dst_ptr, - dst_cast, - src_ptr, - src_cast, - deinit_old, - copy_bytes, - store_dead, - ] - .into_iter(); - - st.make_nop(); - Some(iter) - } else { - None - } - }); - } - } } diff --git a/compiler/rustc_mir_transform/src/lower_slice_len.rs b/compiler/rustc_mir_transform/src/lower_slice_len.rs index ca59d4d12ac..420661f29c8 100644 --- a/compiler/rustc_mir_transform/src/lower_slice_len.rs +++ b/compiler/rustc_mir_transform/src/lower_slice_len.rs @@ -13,22 +13,18 @@ impl<'tcx> crate::MirPass<'tcx> for LowerSliceLenCalls { } fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - lower_slice_len_calls(tcx, body) - } -} - -fn lower_slice_len_calls<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - let language_items = tcx.lang_items(); - let Some(slice_len_fn_item_def_id) = language_items.slice_len_fn() else { - // there is no lang item to compare to :) - return; - }; + let language_items = tcx.lang_items(); + let Some(slice_len_fn_item_def_id) = language_items.slice_len_fn() else { + // there is no lang item to compare to :) + return; + }; - // The one successor remains unchanged, so no need to invalidate - let basic_blocks = body.basic_blocks.as_mut_preserves_cfg(); - for block in basic_blocks { - // lower `<[_]>::len` calls - lower_slice_len_call(block, slice_len_fn_item_def_id); + // The one successor remains unchanged, so no need to invalidate + let basic_blocks = body.basic_blocks.as_mut_preserves_cfg(); + for block in basic_blocks { + // lower `<[_]>::len` calls + lower_slice_len_call(block, slice_len_fn_item_def_id); + } } } 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 37197c3f573..55394e93a5c 100644 --- a/compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs +++ b/compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs @@ -18,7 +18,61 @@ impl<'tcx> crate::MirPass<'tcx> for RemoveNoopLandingPads { fn run_pass(&self, _tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { let def_id = body.source.def_id(); debug!(?def_id); - self.remove_nop_landing_pads(body) + + // Skip the pass if there are no blocks with a resume terminator. + let has_resume = body + .basic_blocks + .iter_enumerated() + .any(|(_bb, block)| matches!(block.terminator().kind, TerminatorKind::UnwindResume)); + if !has_resume { + debug!("remove_noop_landing_pads: no resume block in MIR"); + return; + } + + // make sure there's a resume block without any statements + let resume_block = { + let mut patch = MirPatch::new(body); + let resume_block = patch.resume_block(); + patch.apply(body); + resume_block + }; + debug!("remove_noop_landing_pads: resume block is {:?}", resume_block); + + let mut jumps_folded = 0; + let mut landing_pads_removed = 0; + let mut nop_landing_pads = BitSet::new_empty(body.basic_blocks.len()); + + // This is a post-order traversal, so that if A post-dominates B + // then A will be visited before B. + let postorder: Vec<_> = traversal::postorder(body).map(|(bb, _)| bb).collect(); + for bb in postorder { + debug!(" processing {:?}", bb); + if let Some(unwind) = body[bb].terminator_mut().unwind_mut() { + if let UnwindAction::Cleanup(unwind_bb) = *unwind { + if nop_landing_pads.contains(unwind_bb) { + debug!(" removing noop landing pad"); + landing_pads_removed += 1; + *unwind = UnwindAction::Continue; + } + } + } + + for target in body[bb].terminator_mut().successors_mut() { + if *target != resume_block && nop_landing_pads.contains(*target) { + debug!(" folding noop jump to {:?} to resume block", target); + *target = resume_block; + jumps_folded += 1; + } + } + + let is_nop_landing_pad = self.is_nop_landing_pad(bb, body, &nop_landing_pads); + if is_nop_landing_pad { + nop_landing_pads.insert(bb); + } + debug!(" is_nop_landing_pad({:?}) = {}", bb, is_nop_landing_pad); + } + + debug!("removed {:?} jumps and {:?} landing pads", jumps_folded, landing_pads_removed); } } @@ -82,61 +136,4 @@ impl RemoveNoopLandingPads { | TerminatorKind::InlineAsm { .. } => false, } } - - fn remove_nop_landing_pads(&self, body: &mut Body<'_>) { - // Skip the pass if there are no blocks with a resume terminator. - let has_resume = body - .basic_blocks - .iter_enumerated() - .any(|(_bb, block)| matches!(block.terminator().kind, TerminatorKind::UnwindResume)); - if !has_resume { - debug!("remove_noop_landing_pads: no resume block in MIR"); - return; - } - - // make sure there's a resume block without any statements - let resume_block = { - let mut patch = MirPatch::new(body); - let resume_block = patch.resume_block(); - patch.apply(body); - resume_block - }; - debug!("remove_noop_landing_pads: resume block is {:?}", resume_block); - - let mut jumps_folded = 0; - let mut landing_pads_removed = 0; - let mut nop_landing_pads = BitSet::new_empty(body.basic_blocks.len()); - - // This is a post-order traversal, so that if A post-dominates B - // then A will be visited before B. - let postorder: Vec<_> = traversal::postorder(body).map(|(bb, _)| bb).collect(); - for bb in postorder { - debug!(" processing {:?}", bb); - if let Some(unwind) = body[bb].terminator_mut().unwind_mut() { - if let UnwindAction::Cleanup(unwind_bb) = *unwind { - if nop_landing_pads.contains(unwind_bb) { - debug!(" removing noop landing pad"); - landing_pads_removed += 1; - *unwind = UnwindAction::Continue; - } - } - } - - for target in body[bb].terminator_mut().successors_mut() { - if *target != resume_block && nop_landing_pads.contains(*target) { - debug!(" folding noop jump to {:?} to resume block", target); - *target = resume_block; - jumps_folded += 1; - } - } - - let is_nop_landing_pad = self.is_nop_landing_pad(bb, body, &nop_landing_pads); - if is_nop_landing_pad { - nop_landing_pads.insert(bb); - } - debug!(" is_nop_landing_pad({:?}) = {}", bb, is_nop_landing_pad); - } - - debug!("removed {:?} jumps and {:?} landing pads", jumps_folded, landing_pads_removed); - } } diff --git a/compiler/rustc_mir_transform/src/simplify.rs b/compiler/rustc_mir_transform/src/simplify.rs index cb8e1dfda98..7ed43547e11 100644 --- a/compiler/rustc_mir_transform/src/simplify.rs +++ b/compiler/rustc_mir_transform/src/simplify.rs @@ -381,23 +381,33 @@ impl<'tcx> crate::MirPass<'tcx> for SimplifyLocals { fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { trace!("running SimplifyLocals on {:?}", body.source); - simplify_locals(body, tcx); - } -} -pub(super) fn remove_unused_definitions<'tcx>(body: &mut Body<'tcx>) { - // First, we're going to get a count of *actual* uses for every `Local`. - let mut used_locals = UsedLocals::new(body); + // First, we're going to get a count of *actual* uses for every `Local`. + let mut used_locals = UsedLocals::new(body); - // Next, we're going to remove any `Local` with zero actual uses. When we remove those - // `Locals`, we're also going to subtract any uses of other `Locals` from the `used_locals` - // count. For example, if we removed `_2 = discriminant(_1)`, then we'll subtract one from - // `use_counts[_1]`. That in turn might make `_1` unused, so we loop until we hit a - // fixedpoint where there are no more unused locals. - remove_unused_definitions_helper(&mut used_locals, body); + // Next, we're going to remove any `Local` with zero actual uses. When we remove those + // `Locals`, we're also going to subtract any uses of other `Locals` from the `used_locals` + // count. For example, if we removed `_2 = discriminant(_1)`, then we'll subtract one from + // `use_counts[_1]`. That in turn might make `_1` unused, so we loop until we hit a + // fixedpoint where there are no more unused locals. + remove_unused_definitions_helper(&mut used_locals, body); + + // Finally, we'll actually do the work of shrinking `body.local_decls` and remapping the + // `Local`s. + let map = make_local_map(&mut body.local_decls, &used_locals); + + // Only bother running the `LocalUpdater` if we actually found locals to remove. + if map.iter().any(Option::is_none) { + // Update references to all vars and tmps now + let mut updater = LocalUpdater { map, tcx }; + updater.visit_body_preserves_cfg(body); + + body.local_decls.shrink_to_fit(); + } + } } -fn simplify_locals<'tcx>(body: &mut Body<'tcx>, tcx: TyCtxt<'tcx>) { +pub(super) fn remove_unused_definitions<'tcx>(body: &mut Body<'tcx>) { // First, we're going to get a count of *actual* uses for every `Local`. let mut used_locals = UsedLocals::new(body); @@ -407,18 +417,6 @@ fn simplify_locals<'tcx>(body: &mut Body<'tcx>, tcx: TyCtxt<'tcx>) { // `use_counts[_1]`. That in turn might make `_1` unused, so we loop until we hit a // fixedpoint where there are no more unused locals. remove_unused_definitions_helper(&mut used_locals, body); - - // Finally, we'll actually do the work of shrinking `body.local_decls` and remapping the `Local`s. - let map = make_local_map(&mut body.local_decls, &used_locals); - - // Only bother running the `LocalUpdater` if we actually found locals to remove. - if map.iter().any(Option::is_none) { - // Update references to all vars and tmps now - let mut updater = LocalUpdater { map, tcx }; - updater.visit_body_preserves_cfg(body); - - body.local_decls.shrink_to_fit(); - } } /// Construct the mapping while swapping out unused stuff out from the `vec`. |
