diff options
Diffstat (limited to 'compiler/rustc_mir_transform/src')
| -rw-r--r-- | compiler/rustc_mir_transform/src/deref_separator.rs | 110 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/generator.rs | 4 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/inline.rs | 3 |
3 files changed, 65 insertions, 52 deletions
diff --git a/compiler/rustc_mir_transform/src/deref_separator.rs b/compiler/rustc_mir_transform/src/deref_separator.rs index 57a95a67df7..bfb3ad1be27 100644 --- a/compiler/rustc_mir_transform/src/deref_separator.rs +++ b/compiler/rustc_mir_transform/src/deref_separator.rs @@ -1,9 +1,11 @@ use crate::MirPass; use rustc_index::vec::IndexVec; 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; + pub struct Derefer; pub struct DerefChecker<'tcx> { @@ -17,63 +19,68 @@ impl<'tcx> MutVisitor<'tcx> for DerefChecker<'tcx> { self.tcx } - fn visit_place(&mut self, place: &mut Place<'tcx>, _: PlaceContext, loc: Location) { - let mut place_local = place.local; - let mut last_len = 0; - let mut last_deref_idx = 0; + fn visit_place(&mut self, place: &mut Place<'tcx>, cntxt: PlaceContext, loc: Location) { + if !place.projection.is_empty() + && cntxt != PlaceContext::NonUse(VarDebugInfo) + && place.projection[1..].contains(&ProjectionElem::Deref) + { + let mut place_local = place.local; + let mut last_len = 0; + let mut last_deref_idx = 0; - let mut prev_temp: Option<Local> = None; + let mut prev_temp: Option<Local> = None; - for (idx, (p_ref, p_elem)) in place.iter_projections().enumerate() { - if p_elem == ProjectionElem::Deref && !p_ref.projection.is_empty() { - last_deref_idx = idx; - } - } - - for (idx, (p_ref, p_elem)) in place.iter_projections().enumerate() { - if p_elem == ProjectionElem::Deref && !p_ref.projection.is_empty() { - let ty = p_ref.ty(&self.local_decls, self.tcx).ty; - let temp = self.patcher.new_local_with_info( - ty, - self.local_decls[p_ref.local].source_info.span, - Some(Box::new(LocalInfo::DerefTemp)), - ); - - self.patcher.add_statement(loc, StatementKind::StorageLive(temp)); - - // We are adding current p_ref's projections to our - // temp value, excluding projections we already covered. - let deref_place = Place::from(place_local) - .project_deeper(&p_ref.projection[last_len..], self.tcx); - - self.patcher.add_assign( - loc, - Place::from(temp), - Rvalue::Use(Operand::Move(deref_place)), - ); - place_local = temp; - last_len = p_ref.projection.len(); - - // Change `Place` only if we are actually at the Place's last deref - if idx == last_deref_idx { - let temp_place = - Place::from(temp).project_deeper(&place.projection[idx..], self.tcx); - *place = temp_place; + for (idx, elem) in place.projection[0..].iter().enumerate() { + if *elem == ProjectionElem::Deref { + last_deref_idx = idx; } - - // We are destroying the previous temp since it's no longer used. - if let Some(prev_temp) = prev_temp { - self.patcher.add_statement(loc, StatementKind::StorageDead(prev_temp)); + } + for (idx, (p_ref, p_elem)) in place.iter_projections().enumerate() { + if !p_ref.projection.is_empty() && p_elem == ProjectionElem::Deref { + let ty = p_ref.ty(&self.local_decls, self.tcx).ty; + let temp = self.patcher.new_local_with_info( + ty, + self.local_decls[p_ref.local].source_info.span, + Some(Box::new(LocalInfo::DerefTemp)), + ); + + self.patcher.add_statement(loc, StatementKind::StorageLive(temp)); + + // We are adding current p_ref's projections to our + // temp value, excluding projections we already covered. + let deref_place = Place::from(place_local) + .project_deeper(&p_ref.projection[last_len..], self.tcx); + + self.patcher.add_assign( + loc, + Place::from(temp), + Rvalue::Use(Operand::Move(deref_place)), + ); + place_local = temp; + last_len = p_ref.projection.len(); + + // Change `Place` only if we are actually at the Place's last deref + if idx == last_deref_idx { + let temp_place = + Place::from(temp).project_deeper(&place.projection[idx..], self.tcx); + *place = temp_place; + } + + // We are destroying the previous temp since it's no longer used. + if let Some(prev_temp) = prev_temp { + self.patcher.add_statement(loc, StatementKind::StorageDead(prev_temp)); + } + + prev_temp = Some(temp); } - - prev_temp = Some(temp); } - } - // Since we won't be able to reach final temp, we destroy it outside the loop. - if let Some(prev_temp) = prev_temp { - let last_loc = Location { block: loc.block, statement_index: loc.statement_index + 1 }; - self.patcher.add_statement(last_loc, StatementKind::StorageDead(prev_temp)); + // Since we won't be able to reach final temp, we destroy it outside the loop. + if let Some(prev_temp) = prev_temp { + let last_loc = + Location { block: loc.block, statement_index: loc.statement_index + 1 }; + self.patcher.add_statement(last_loc, StatementKind::StorageDead(prev_temp)); + } } } } @@ -92,5 +99,6 @@ pub fn deref_finder<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { impl<'tcx> MirPass<'tcx> for Derefer { fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { deref_finder(tcx, body); + body.phase = MirPhase::Derefered; } } diff --git a/compiler/rustc_mir_transform/src/generator.rs b/compiler/rustc_mir_transform/src/generator.rs index 4a3505ca3ff..9eb77f60213 100644 --- a/compiler/rustc_mir_transform/src/generator.rs +++ b/compiler/rustc_mir_transform/src/generator.rs @@ -49,6 +49,7 @@ //! For generators with state 1 (returned) and state 2 (poisoned) it does nothing. //! Otherwise it drops all the values in scope at the last suspension point. +use crate::deref_separator::deref_finder; use crate::simplify; use crate::util::expand_aggregate; use crate::MirPass; @@ -1368,6 +1369,9 @@ impl<'tcx> MirPass<'tcx> for StateTransform { // Create the Generator::resume function create_generator_resume_function(tcx, transform, body, can_return); + + // Run derefer to fix Derefs that are not in the first place + deref_finder(tcx, body); } } diff --git a/compiler/rustc_mir_transform/src/inline.rs b/compiler/rustc_mir_transform/src/inline.rs index 66fb01bd464..9526c0acc66 100644 --- a/compiler/rustc_mir_transform/src/inline.rs +++ b/compiler/rustc_mir_transform/src/inline.rs @@ -1,5 +1,5 @@ //! Inlining pass for MIR functions - +use crate::deref_separator::deref_finder; use rustc_attr::InlineAttr; use rustc_index::bit_set::BitSet; use rustc_index::vec::Idx; @@ -53,6 +53,7 @@ impl<'tcx> MirPass<'tcx> for Inline { debug!("running simplify cfg on {:?}", body.source); CfgSimplifier::new(body).simplify(); remove_dead_blocks(tcx, body); + deref_finder(tcx, body); } } } |