From 7547084ff673dcfdb2c6bcf7dc7a81190513ed40 Mon Sep 17 00:00:00 2001 From: Jakob Degen Date: Tue, 2 Aug 2022 20:06:16 -0700 Subject: [PATCH] Add option to `mir::MutVisitor` to not invalidate CFG. This also applies that option to some uses of the visitor --- compiler/rustc_middle/src/mir/visit.rs | 155 +++++++++++------- .../src/cleanup_post_borrowck.rs | 2 +- .../rustc_mir_transform/src/const_prop.rs | 2 +- .../src/deref_separator.rs | 2 +- .../src/elaborate_box_derefs.rs | 2 +- compiler/rustc_mir_transform/src/nrvo.rs | 4 +- .../rustc_mir_transform/src/reveal_all.rs | 2 +- compiler/rustc_mir_transform/src/simplify.rs | 4 +- 8 files changed, 101 insertions(+), 72 deletions(-) diff --git a/compiler/rustc_middle/src/mir/visit.rs b/compiler/rustc_middle/src/mir/visit.rs index 891608764017c..4a85defb1ed84 100644 --- a/compiler/rustc_middle/src/mir/visit.rs +++ b/compiler/rustc_middle/src/mir/visit.rs @@ -80,6 +80,8 @@ macro_rules! make_mir_visitor { self.super_body(body); } + extra_body_methods!($($mutability)?); + fn visit_basic_block_data( &mut self, block: BasicBlock, @@ -287,63 +289,7 @@ macro_rules! make_mir_visitor { &mut self, body: &$($mutability)? Body<'tcx>, ) { - let span = body.span; - if let Some(gen) = &$($mutability)? body.generator { - if let Some(yield_ty) = $(& $mutability)? gen.yield_ty { - self.visit_ty( - yield_ty, - TyContext::YieldTy(SourceInfo::outermost(span)) - ); - } - } - - // for best performance, we want to use an iterator rather - // than a for-loop, to avoid calling `body::Body::invalidate` for - // each basic block. - #[allow(unused_macro_rules)] - macro_rules! basic_blocks { - (mut) => (body.basic_blocks_mut().iter_enumerated_mut()); - () => (body.basic_blocks().iter_enumerated()); - } - for (bb, data) in basic_blocks!($($mutability)?) { - self.visit_basic_block_data(bb, data); - } - - for scope in &$($mutability)? body.source_scopes { - self.visit_source_scope_data(scope); - } - - self.visit_ty( - $(& $mutability)? body.return_ty(), - TyContext::ReturnTy(SourceInfo::outermost(body.span)) - ); - - for local in body.local_decls.indices() { - self.visit_local_decl(local, & $($mutability)? body.local_decls[local]); - } - - #[allow(unused_macro_rules)] - macro_rules! type_annotations { - (mut) => (body.user_type_annotations.iter_enumerated_mut()); - () => (body.user_type_annotations.iter_enumerated()); - } - - for (index, annotation) in type_annotations!($($mutability)?) { - self.visit_user_type_annotation( - index, annotation - ); - } - - for var_debug_info in &$($mutability)? body.var_debug_info { - self.visit_var_debug_info(var_debug_info); - } - - self.visit_span($(& $mutability)? body.span); - - for const_ in &$($mutability)? body.required_consts { - let location = START_BLOCK.start_location(); - self.visit_constant(const_, location); - } + super_body!(self, body, $($mutability, true)?); } fn super_basic_block_data(&mut self, @@ -982,12 +928,7 @@ macro_rules! make_mir_visitor { body: &$($mutability)? Body<'tcx>, location: Location ) { - #[allow(unused_macro_rules)] - macro_rules! basic_blocks { - (mut) => (body.basic_blocks_mut()); - () => (body.basic_blocks()); - } - let basic_block = & $($mutability)? basic_blocks!($($mutability)?)[location.block]; + let basic_block = & $($mutability)? basic_blocks!(body, $($mutability, true)?)[location.block]; if basic_block.statements.len() == location.statement_index { if let Some(ref $($mutability)? terminator) = basic_block.terminator { self.visit_terminator(terminator, location) @@ -1002,6 +943,94 @@ macro_rules! make_mir_visitor { } } +macro_rules! basic_blocks { + ($body:ident, mut, true) => { + $body.basic_blocks.as_mut() + }; + ($body:ident, mut, false) => { + $body.basic_blocks.as_mut_preserves_cfg() + }; + ($body:ident,) => { + $body.basic_blocks() + }; +} + +macro_rules! basic_blocks_iter { + ($body:ident, mut, $invalidate:tt) => { + basic_blocks!($body, mut, $invalidate).iter_enumerated_mut() + }; + ($body:ident,) => { + basic_blocks!($body,).iter_enumerated() + }; +} + +macro_rules! extra_body_methods { + (mut) => { + fn visit_body_preserves_cfg(&mut self, body: &mut Body<'tcx>) { + self.super_body_preserves_cfg(body); + } + + fn super_body_preserves_cfg(&mut self, body: &mut Body<'tcx>) { + super_body!(self, body, mut, false); + } + }; + () => {}; +} + +macro_rules! super_body { + ($self:ident, $body:ident, $($mutability:ident, $invalidate:tt)?) => { + let span = $body.span; + if let Some(gen) = &$($mutability)? $body.generator { + if let Some(yield_ty) = $(& $mutability)? gen.yield_ty { + $self.visit_ty( + yield_ty, + TyContext::YieldTy(SourceInfo::outermost(span)) + ); + } + } + + for (bb, data) in basic_blocks_iter!($body, $($mutability, $invalidate)?) { + $self.visit_basic_block_data(bb, data); + } + + for scope in &$($mutability)? $body.source_scopes { + $self.visit_source_scope_data(scope); + } + + $self.visit_ty( + $(& $mutability)? $body.return_ty(), + TyContext::ReturnTy(SourceInfo::outermost($body.span)) + ); + + for local in $body.local_decls.indices() { + $self.visit_local_decl(local, & $($mutability)? $body.local_decls[local]); + } + + #[allow(unused_macro_rules)] + macro_rules! type_annotations { + (mut) => ($body.user_type_annotations.iter_enumerated_mut()); + () => ($body.user_type_annotations.iter_enumerated()); + } + + for (index, annotation) in type_annotations!($($mutability)?) { + $self.visit_user_type_annotation( + index, annotation + ); + } + + for var_debug_info in &$($mutability)? $body.var_debug_info { + $self.visit_var_debug_info(var_debug_info); + } + + $self.visit_span($(& $mutability)? $body.span); + + for const_ in &$($mutability)? $body.required_consts { + let location = START_BLOCK.start_location(); + $self.visit_constant(const_, location); + } + } +} + macro_rules! visit_place_fns { (mut) => { fn tcx<'a>(&'a self) -> TyCtxt<'tcx>; diff --git a/compiler/rustc_mir_transform/src/cleanup_post_borrowck.rs b/compiler/rustc_mir_transform/src/cleanup_post_borrowck.rs index 611d29a4ee29a..3378923c22c36 100644 --- a/compiler/rustc_mir_transform/src/cleanup_post_borrowck.rs +++ b/compiler/rustc_mir_transform/src/cleanup_post_borrowck.rs @@ -33,7 +33,7 @@ pub struct DeleteNonCodegenStatements<'tcx> { impl<'tcx> MirPass<'tcx> for CleanupNonCodegenStatements { fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { let mut delete = DeleteNonCodegenStatements { tcx }; - delete.visit_body(body); + delete.visit_body_preserves_cfg(body); body.user_type_annotations.raw.clear(); for decl in &mut body.local_decls { diff --git a/compiler/rustc_mir_transform/src/const_prop.rs b/compiler/rustc_mir_transform/src/const_prop.rs index fbc0a767f0766..98016659a05f7 100644 --- a/compiler/rustc_mir_transform/src/const_prop.rs +++ b/compiler/rustc_mir_transform/src/const_prop.rs @@ -951,7 +951,7 @@ impl<'tcx> MutVisitor<'tcx> for ConstPropagator<'_, 'tcx> { } fn visit_body(&mut self, body: &mut Body<'tcx>) { - for (bb, data) in body.basic_blocks_mut().iter_enumerated_mut() { + for (bb, data) in body.basic_blocks.as_mut_preserves_cfg().iter_enumerated_mut() { self.visit_basic_block_data(bb, data); } } diff --git a/compiler/rustc_mir_transform/src/deref_separator.rs b/compiler/rustc_mir_transform/src/deref_separator.rs index a00bb16f7ac67..87d7b664015a9 100644 --- a/compiler/rustc_mir_transform/src/deref_separator.rs +++ b/compiler/rustc_mir_transform/src/deref_separator.rs @@ -90,7 +90,7 @@ pub fn deref_finder<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { let patch = MirPatch::new(body); let mut checker = DerefChecker { tcx, patcher: patch, local_decls: body.local_decls.clone() }; - for (bb, data) in body.basic_blocks_mut().iter_enumerated_mut() { + for (bb, data) in body.basic_blocks.as_mut_preserves_cfg().iter_enumerated_mut() { checker.visit_basic_block_data(bb, data); } diff --git a/compiler/rustc_mir_transform/src/elaborate_box_derefs.rs b/compiler/rustc_mir_transform/src/elaborate_box_derefs.rs index 44e3945d6fc89..76b4cdd2ecd3c 100644 --- a/compiler/rustc_mir_transform/src/elaborate_box_derefs.rs +++ b/compiler/rustc_mir_transform/src/elaborate_box_derefs.rs @@ -116,7 +116,7 @@ impl<'tcx> MirPass<'tcx> for ElaborateBoxDerefs { ElaborateBoxDerefVisitor { tcx, unique_did, nonnull_did, local_decls, patch }; for (block, BasicBlockData { statements, terminator, .. }) in - body.basic_blocks.as_mut().iter_enumerated_mut() + body.basic_blocks.as_mut_preserves_cfg().iter_enumerated_mut() { let mut index = 0; for statement in statements { diff --git a/compiler/rustc_mir_transform/src/nrvo.rs b/compiler/rustc_mir_transform/src/nrvo.rs index bb063915f55a9..42d732730eccc 100644 --- a/compiler/rustc_mir_transform/src/nrvo.rs +++ b/compiler/rustc_mir_transform/src/nrvo.rs @@ -53,10 +53,10 @@ impl<'tcx> MirPass<'tcx> for RenameReturnPlace { def_id, returned_local ); - RenameToReturnPlace { tcx, to_rename: returned_local }.visit_body(body); + RenameToReturnPlace { tcx, to_rename: returned_local }.visit_body_preserves_cfg(body); // Clean up the `NOP`s we inserted for statements made useless by our renaming. - for block_data in body.basic_blocks_mut() { + for block_data in body.basic_blocks.as_mut_preserves_cfg() { block_data.statements.retain(|stmt| stmt.kind != mir::StatementKind::Nop); } diff --git a/compiler/rustc_mir_transform/src/reveal_all.rs b/compiler/rustc_mir_transform/src/reveal_all.rs index 4919ad40098cb..abe6cb285f505 100644 --- a/compiler/rustc_mir_transform/src/reveal_all.rs +++ b/compiler/rustc_mir_transform/src/reveal_all.rs @@ -19,7 +19,7 @@ impl<'tcx> MirPass<'tcx> for RevealAll { } let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id()); - RevealAllVisitor { tcx, param_env }.visit_body(body); + RevealAllVisitor { tcx, param_env }.visit_body_preserves_cfg(body); } } diff --git a/compiler/rustc_mir_transform/src/simplify.rs b/compiler/rustc_mir_transform/src/simplify.rs index 180f4c7dcd6e8..7a6ca917d0ffd 100644 --- a/compiler/rustc_mir_transform/src/simplify.rs +++ b/compiler/rustc_mir_transform/src/simplify.rs @@ -412,7 +412,7 @@ pub fn simplify_locals<'tcx>(body: &mut Body<'tcx>, tcx: TyCtxt<'tcx>) { if map.iter().any(Option::is_none) { // Update references to all vars and tmps now let mut updater = LocalUpdater { map, tcx }; - updater.visit_body(body); + updater.visit_body_preserves_cfg(body); body.local_decls.shrink_to_fit(); } @@ -548,7 +548,7 @@ fn remove_unused_definitions(used_locals: &mut UsedLocals, body: &mut Body<'_>) while modified { modified = false; - for data in body.basic_blocks_mut() { + for data in body.basic_blocks.as_mut_preserves_cfg() { // Remove unnecessary StorageLive and StorageDead annotations. data.statements.retain(|statement| { let keep = match &statement.kind {