From 17d40c6057c88f4c432b0d7bac88e1b84cb7e67f Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:03:36 +0200 Subject: Adding upstream version 1.65.0+dfsg1. Signed-off-by: Daniel Baumann --- compiler/rustc_mir_build/src/build/block.rs | 213 ++++++- .../rustc_mir_build/src/build/expr/as_constant.rs | 37 +- .../rustc_mir_build/src/build/expr/as_place.rs | 144 ++--- .../rustc_mir_build/src/build/expr/as_rvalue.rs | 31 +- compiler/rustc_mir_build/src/build/expr/as_temp.rs | 5 +- compiler/rustc_mir_build/src/build/expr/into.rs | 25 +- compiler/rustc_mir_build/src/build/expr/stmt.rs | 22 +- compiler/rustc_mir_build/src/build/matches/mod.rs | 157 +++--- .../rustc_mir_build/src/build/matches/simplify.rs | 24 +- compiler/rustc_mir_build/src/build/matches/test.rs | 50 +- compiler/rustc_mir_build/src/build/matches/util.rs | 14 +- compiler/rustc_mir_build/src/build/mod.rs | 616 ++++++++------------- compiler/rustc_mir_build/src/build/scope.rs | 38 +- 13 files changed, 680 insertions(+), 696 deletions(-) (limited to 'compiler/rustc_mir_build/src/build') diff --git a/compiler/rustc_mir_build/src/build/block.rs b/compiler/rustc_mir_build/src/build/block.rs index 687560012..784583d94 100644 --- a/compiler/rustc_mir_build/src/build/block.rs +++ b/compiler/rustc_mir_build/src/build/block.rs @@ -1,6 +1,7 @@ use crate::build::matches::ArmHasGuard; use crate::build::ForGuard::OutsideGuard; use crate::build::{BlockAnd, BlockAndExtension, BlockFrame, Builder}; +use rustc_middle::middle::region::Scope; use rustc_middle::thir::*; use rustc_middle::{mir::*, ty}; use rustc_span::Span; @@ -10,7 +11,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { &mut self, destination: Place<'tcx>, block: BasicBlock, - ast_block: &Block, + ast_block: BlockId, source_info: SourceInfo, ) -> BlockAnd<()> { let Block { @@ -21,7 +22,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { expr, targeted_by_break, safety_mode, - } = *ast_block; + } = self.thir[ast_block]; let expr = expr.map(|expr| &self.thir[expr]); self.in_opt_scope(opt_destruction_scope.map(|de| (de, source_info)), move |this| { this.in_scope((region_scope, source_info), LintLevel::Inherited, move |this| { @@ -34,10 +35,19 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { &stmts, expr, safety_mode, + region_scope, )) }) } else { - this.ast_block_stmts(destination, block, span, &stmts, expr, safety_mode) + this.ast_block_stmts( + destination, + block, + span, + &stmts, + expr, + safety_mode, + region_scope, + ) } }) }) @@ -51,6 +61,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { stmts: &[StmtId], expr: Option<&Expr<'tcx>>, safety_mode: BlockSafety, + region_scope: Scope, ) -> BlockAnd<()> { let this = self; @@ -73,6 +84,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let mut let_scope_stack = Vec::with_capacity(8); let outer_source_scope = this.source_scope; let outer_in_scope_unsafe = this.in_scope_unsafe; + // This scope information is kept for breaking out of the parent remainder scope in case + // one let-else pattern matching fails. + // By doing so, we can be sure that even temporaries that receive extended lifetime + // assignments are dropped, too. + let mut last_remainder_scope = region_scope; this.update_source_scope_for_safety_mode(span, safety_mode); let source_info = this.source_info(span); @@ -93,15 +109,172 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { ) ); } + StmtKind::Let { + remainder_scope, + init_scope, + pattern, + initializer: Some(initializer), + lint_level, + else_block: Some(else_block), + } => { + // When lowering the statement `let = else { };`, + // the `` block is nested in the parent scope enclosing this statment. + // That scope is usually either the enclosing block scope, + // or the remainder scope of the last statement. + // This is to make sure that temporaries instantiated in `` are dropped + // as well. + // In addition, even though bindings in `` only come into scope if + // the pattern matching passes, in the MIR building the storages for them + // are declared as live any way. + // This is similar to `let x;` statements without an initializer expression, + // where the value of `x` in this example may or may be assigned, + // because the storage for their values may not be live after all due to + // failure in pattern matching. + // For this reason, we declare those storages as live but we do not schedule + // any drop yet- they are scheduled later after the pattern matching. + // The generated MIR will have `StorageDead` whenever the control flow breaks out + // of the parent scope, regardless of the result of the pattern matching. + // However, the drops are inserted in MIR only when the control flow breaks out of + // the scope of the remainder scope associated with this `let .. else` statement. + // Pictorial explanation of the scope structure: + // ┌─────────────────────────────────┐ + // │ Scope of the enclosing block, │ + // │ or the last remainder scope │ + // │ ┌───────────────────────────┐ │ + // │ │ Scope for block │ │ + // │ └───────────────────────────┘ │ + // │ ┌───────────────────────────┐ │ + // │ │ Remainder scope of │ │ + // │ │ this let-else statement │ │ + // │ │ ┌─────────────────────┐ │ │ + // │ │ │ scope │ │ │ + // │ │ └─────────────────────┘ │ │ + // │ │ extended temporaries in │ │ + // │ │ lives in this │ │ + // │ │ scope │ │ + // │ │ ┌─────────────────────┐ │ │ + // │ │ │ Scopes for the rest │ │ │ + // │ │ └─────────────────────┘ │ │ + // │ └───────────────────────────┘ │ + // └─────────────────────────────────┘ + // Generated control flow: + // │ let Some(x) = y() else { return; } + // │ + // ┌────────▼───────┐ + // │ evaluate y() │ + // └────────┬───────┘ + // │ ┌────────────────┐ + // ┌────────▼───────┐ │Drop temporaries│ + // │Test the pattern├──────►in y() │ + // └────────┬───────┘ │because breaking│ + // │ │out of │ + // ┌────────▼───────┐ │scope │ + // │Move value into │ └───────┬────────┘ + // │binding x │ │ + // └────────┬───────┘ ┌───────▼────────┐ + // │ │Drop extended │ + // ┌────────▼───────┐ │temporaries in │ + // │Drop temporaries│ │ because │ + // │in y() │ │breaking out of │ + // │because breaking│ │remainder scope │ + // │out of │ └───────┬────────┘ + // │scope │ │ + // └────────┬───────┘ ┌───────▼────────┐ + // │ │Enter ├────────► + // ┌────────▼───────┐ │block │ return; + // │Continue... │ └────────────────┘ + // └────────────────┘ + + let ignores_expr_result = matches!(pattern.kind, PatKind::Wild); + this.block_context.push(BlockFrame::Statement { ignores_expr_result }); + + // Lower the `else` block first because its parent scope is actually + // enclosing the rest of the `let .. else ..` parts. + let else_block_span = this.thir[*else_block].span; + // This place is not really used because this destination place + // should never be used to take values at the end of the failure + // block. + let dummy_place = this.temp(this.tcx.types.never, else_block_span); + let failure_entry = this.cfg.start_new_block(); + let failure_block; + unpack!( + failure_block = this.ast_block( + dummy_place, + failure_entry, + *else_block, + this.source_info(else_block_span), + ) + ); + this.cfg.terminate( + failure_block, + this.source_info(else_block_span), + TerminatorKind::Unreachable, + ); + + // Declare the bindings, which may create a source scope. + let remainder_span = remainder_scope.span(this.tcx, this.region_scope_tree); + this.push_scope((*remainder_scope, source_info)); + let_scope_stack.push(remainder_scope); + + let visibility_scope = + Some(this.new_source_scope(remainder_span, LintLevel::Inherited, None)); + + let init = &this.thir[*initializer]; + let initializer_span = init.span; + this.declare_bindings( + visibility_scope, + remainder_span, + pattern, + ArmHasGuard(false), + Some((None, initializer_span)), + ); + this.visit_primary_bindings( + pattern, + UserTypeProjections::none(), + &mut |this, _, _, _, node, span, _, _| { + this.storage_live_binding(block, node, span, OutsideGuard, true); + }, + ); + let failure = unpack!( + block = this.in_opt_scope( + opt_destruction_scope.map(|de| (de, source_info)), + |this| { + let scope = (*init_scope, source_info); + this.in_scope(scope, *lint_level, |this| { + this.ast_let_else( + block, + init, + initializer_span, + *else_block, + &last_remainder_scope, + pattern, + ) + }) + } + ) + ); + this.cfg.goto(failure, source_info, failure_entry); + + if let Some(source_scope) = visibility_scope { + this.source_scope = source_scope; + } + last_remainder_scope = *remainder_scope; + } + StmtKind::Let { init_scope, initializer: None, else_block: Some(_), .. } => { + span_bug!( + init_scope.span(this.tcx, this.region_scope_tree), + "initializer is missing, but else block is present in this let binding", + ) + } StmtKind::Let { remainder_scope, init_scope, ref pattern, initializer, lint_level, - else_block, + else_block: None, } => { - let ignores_expr_result = matches!(*pattern.kind, PatKind::Wild); + let ignores_expr_result = matches!(pattern.kind, PatKind::Wild); this.block_context.push(BlockFrame::Statement { ignores_expr_result }); // Enter the remainder scope, i.e., the bindings' destruction scope. @@ -125,27 +298,14 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { |this| { let scope = (*init_scope, source_info); this.in_scope(scope, *lint_level, |this| { - if let Some(else_block) = else_block { - this.ast_let_else( - block, - init, - initializer_span, - else_block, - visibility_scope, - *remainder_scope, - remainder_span, - pattern, - ) - } else { - this.declare_bindings( - visibility_scope, - remainder_span, - pattern, - ArmHasGuard(false), - Some((None, initializer_span)), - ); - this.expr_into_pattern(block, pattern.clone(), init) // irrefutable pattern - } + this.declare_bindings( + visibility_scope, + remainder_span, + pattern, + ArmHasGuard(false), + Some((None, initializer_span)), + ); + this.expr_into_pattern(block, &pattern, init) // irrefutable pattern }) }, ) @@ -178,6 +338,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { if let Some(source_scope) = visibility_scope { this.source_scope = source_scope; } + last_remainder_scope = *remainder_scope; } } diff --git a/compiler/rustc_mir_build/src/build/expr/as_constant.rs b/compiler/rustc_mir_build/src/build/expr/as_constant.rs index 648d10b9e..c9bec130c 100644 --- a/compiler/rustc_mir_build/src/build/expr/as_constant.rs +++ b/compiler/rustc_mir_build/src/build/expr/as_constant.rs @@ -2,26 +2,18 @@ use crate::build::{parse_float_into_constval, Builder}; use rustc_ast as ast; -use rustc_hir::def_id::DefId; use rustc_middle::mir::interpret::{ Allocation, ConstValue, LitToConstError, LitToConstInput, Scalar, }; use rustc_middle::mir::*; use rustc_middle::thir::*; -use rustc_middle::ty::subst::SubstsRef; -use rustc_middle::ty::{self, CanonicalUserTypeAnnotation, Ty, TyCtxt}; +use rustc_middle::ty::{self, CanonicalUserTypeAnnotation, TyCtxt}; use rustc_target::abi::Size; impl<'a, 'tcx> Builder<'a, 'tcx> { /// Compile `expr`, yielding a compile-time constant. Assumes that /// `expr` is a valid compile-time constant! pub(crate) fn as_constant(&mut self, expr: &Expr<'tcx>) -> Constant<'tcx> { - let create_uneval_from_def_id = - |tcx: TyCtxt<'tcx>, def_id: DefId, ty: Ty<'tcx>, substs: SubstsRef<'tcx>| { - let uneval = ty::Unevaluated::new(ty::WithOptConstParam::unknown(def_id), substs); - tcx.mk_const(ty::ConstS { kind: ty::ConstKind::Unevaluated(uneval), ty }) - }; - let this = self; let tcx = this.tcx; let Expr { ty, temp_lifetime: _, span, ref kind } = *expr; @@ -41,11 +33,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { Constant { span, user_ty: None, literal } } - ExprKind::NonHirLiteral { lit, user_ty } => { - let user_ty = user_ty.map(|user_ty| { + ExprKind::NonHirLiteral { lit, ref user_ty } => { + let user_ty = user_ty.as_ref().map(|user_ty| { this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation { span, - user_ty, + user_ty: user_ty.clone(), inferred_ty: ty, }) }); @@ -53,11 +45,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { Constant { span, user_ty: user_ty, literal } } - ExprKind::ZstLiteral { user_ty } => { - let user_ty = user_ty.map(|user_ty| { + ExprKind::ZstLiteral { ref user_ty } => { + let user_ty = user_ty.as_ref().map(|user_ty| { this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation { span, - user_ty, + user_ty: user_ty.clone(), inferred_ty: ty, }) }); @@ -65,15 +57,17 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { Constant { span, user_ty: user_ty, literal } } - ExprKind::NamedConst { def_id, substs, user_ty } => { - let user_ty = user_ty.map(|user_ty| { + ExprKind::NamedConst { def_id, substs, ref user_ty } => { + let user_ty = user_ty.as_ref().map(|user_ty| { this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation { span, - user_ty, + user_ty: user_ty.clone(), inferred_ty: ty, }) }); - let literal = ConstantKind::Ty(create_uneval_from_def_id(tcx, def_id, ty, substs)); + + let uneval = ty::Unevaluated::new(ty::WithOptConstParam::unknown(def_id), substs); + let literal = ConstantKind::Unevaluated(uneval, ty); Constant { user_ty, span, literal } } @@ -85,7 +79,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { Constant { user_ty: None, span, literal } } ExprKind::ConstBlock { did: def_id, substs } => { - let literal = ConstantKind::Ty(create_uneval_from_def_id(tcx, def_id, ty, substs)); + let uneval = ty::Unevaluated::new(ty::WithOptConstParam::unknown(def_id), substs); + let literal = ConstantKind::Unevaluated(uneval, ty); Constant { user_ty: None, span, literal } } @@ -144,7 +139,7 @@ pub(crate) fn lit_to_mir_constant<'tcx>( } (ast::LitKind::Bool(b), ty::Bool) => ConstValue::Scalar(Scalar::from_bool(*b)), (ast::LitKind::Char(c), ty::Char) => ConstValue::Scalar(Scalar::from_char(*c)), - (ast::LitKind::Err(_), _) => return Err(LitToConstError::Reported), + (ast::LitKind::Err, _) => return Err(LitToConstError::Reported), _ => return Err(LitToConstError::TypeError), }; diff --git a/compiler/rustc_mir_build/src/build/expr/as_place.rs b/compiler/rustc_mir_build/src/build/expr/as_place.rs index 0c06aad4e..ebb56e5a2 100644 --- a/compiler/rustc_mir_build/src/build/expr/as_place.rs +++ b/compiler/rustc_mir_build/src/build/expr/as_place.rs @@ -2,7 +2,7 @@ use crate::build::expr::category::Category; use crate::build::ForGuard::{OutsideGuard, RefWithinGuard}; -use crate::build::{BlockAnd, BlockAndExtension, Builder}; +use crate::build::{BlockAnd, BlockAndExtension, Builder, Capture, CaptureMap}; use rustc_hir::def_id::LocalDefId; use rustc_middle::hir::place::Projection as HirProjection; use rustc_middle::hir::place::ProjectionKind as HirProjectionKind; @@ -59,8 +59,6 @@ pub(crate) enum PlaceBase { var_hir_id: LocalVarId, /// DefId of the closure closure_def_id: LocalDefId, - /// The trait closure implements, `Fn`, `FnMut`, `FnOnce` - closure_kind: ty::ClosureKind, }, } @@ -145,27 +143,6 @@ fn is_ancestor_or_same_capture( iter::zip(proj_possible_ancestor, proj_capture).all(|(a, b)| a == b) } -/// Computes the index of a capture within the desugared closure provided the closure's -/// `closure_min_captures` and the capture's index of the capture in the -/// `ty::MinCaptureList` of the root variable `var_hir_id`. -fn compute_capture_idx<'tcx>( - closure_min_captures: &ty::RootVariableMinCaptureList<'tcx>, - var_hir_id: LocalVarId, - root_var_idx: usize, -) -> usize { - let mut res = 0; - for (var_id, capture_list) in closure_min_captures { - if *var_id == var_hir_id.0 { - res += root_var_idx; - break; - } else { - res += capture_list.len(); - } - } - - res -} - /// Given a closure, returns the index of a capture within the desugared closure struct and the /// `ty::CapturedPlace` which is the ancestor of the Place represented using the `var_hir_id` /// and `projection`. @@ -174,27 +151,17 @@ fn compute_capture_idx<'tcx>( /// /// Returns None, when the ancestor is not found. fn find_capture_matching_projections<'a, 'tcx>( - typeck_results: &'a ty::TypeckResults<'tcx>, + upvars: &'a CaptureMap<'tcx>, var_hir_id: LocalVarId, - closure_def_id: LocalDefId, projections: &[PlaceElem<'tcx>], -) -> Option<(usize, &'a ty::CapturedPlace<'tcx>)> { - let closure_min_captures = typeck_results.closure_min_captures.get(&closure_def_id)?; - let root_variable_min_captures = closure_min_captures.get(&var_hir_id.0)?; - +) -> Option<(usize, &'a Capture<'tcx>)> { let hir_projections = convert_to_hir_projections_and_truncate_for_capture(projections); - // If an ancestor is found, `idx` is the index within the list of captured places - // for root variable `var_hir_id` and `capture` is the `ty::CapturedPlace` itself. - let (idx, capture) = root_variable_min_captures.iter().enumerate().find(|(_, capture)| { + upvars.get_by_key_enumerated(var_hir_id.0).find(|(_, capture)| { let possible_ancestor_proj_kinds: Vec<_> = - capture.place.projections.iter().map(|proj| proj.kind).collect(); + capture.captured_place.place.projections.iter().map(|proj| proj.kind).collect(); is_ancestor_or_same_capture(&possible_ancestor_proj_kinds, &hir_projections) - })?; - - // Convert index to be from the perspective of the entire closure_min_captures map - // instead of just the root variable capture list - Some((compute_capture_idx(closure_min_captures, var_hir_id, idx), capture)) + }) } /// Takes a PlaceBuilder and resolves the upvar (if any) within it, so that the @@ -204,24 +171,15 @@ fn find_capture_matching_projections<'a, 'tcx>( fn to_upvars_resolved_place_builder<'a, 'tcx>( from_builder: PlaceBuilder<'tcx>, tcx: TyCtxt<'tcx>, - typeck_results: &'a ty::TypeckResults<'tcx>, + upvars: &'a CaptureMap<'tcx>, ) -> Result, PlaceBuilder<'tcx>> { match from_builder.base { PlaceBase::Local(_) => Ok(from_builder), - PlaceBase::Upvar { var_hir_id, closure_def_id, closure_kind } => { - let mut upvar_resolved_place_builder = PlaceBuilder::from(ty::CAPTURE_STRUCT_LOCAL); - match closure_kind { - ty::ClosureKind::Fn | ty::ClosureKind::FnMut => { - upvar_resolved_place_builder = upvar_resolved_place_builder.deref(); - } - ty::ClosureKind::FnOnce => {} - } - + PlaceBase::Upvar { var_hir_id, closure_def_id } => { let Some((capture_index, capture)) = find_capture_matching_projections( - typeck_results, + upvars, var_hir_id, - closure_def_id, &from_builder.projection, ) else { let closure_span = tcx.def_span(closure_def_id); @@ -241,39 +199,17 @@ fn to_upvars_resolved_place_builder<'a, 'tcx>( return Err(from_builder); }; - // We won't be building MIR if the closure wasn't local - let closure_hir_id = tcx.hir().local_def_id_to_hir_id(closure_def_id); - let closure_ty = typeck_results.node_type(closure_hir_id); - - let substs = match closure_ty.kind() { - ty::Closure(_, substs) => ty::UpvarSubsts::Closure(substs), - ty::Generator(_, substs, _) => ty::UpvarSubsts::Generator(substs), - _ => bug!("Lowering capture for non-closure type {:?}", closure_ty), - }; - // Access the capture by accessing the field within the Closure struct. - // - // We must have inferred the capture types since we are building MIR, therefore - // it's safe to call `tuple_element_ty` and we can unwrap here because - // we know that the capture exists and is the `capture_index`-th capture. - let var_ty = substs.tupled_upvars_ty().tuple_fields()[capture_index]; - - upvar_resolved_place_builder = - upvar_resolved_place_builder.field(Field::new(capture_index), var_ty); - - // If the variable is captured via ByRef(Immutable/Mutable) Borrow, - // we need to deref it - upvar_resolved_place_builder = match capture.info.capture_kind { - ty::UpvarCapture::ByRef(_) => upvar_resolved_place_builder.deref(), - ty::UpvarCapture::ByValue => upvar_resolved_place_builder, - }; + let capture_info = &upvars[capture_index]; + + let mut upvar_resolved_place_builder = PlaceBuilder::from(capture_info.use_place); // We used some of the projections to build the capture itself, // now we apply the remaining to the upvar resolved place. let remaining_projections = strip_prefix( - capture.place.base_ty, + capture.captured_place.place.base_ty, from_builder.projection, - &capture.place.projections, + &capture.captured_place.place.projections, ); upvar_resolved_place_builder.projection.extend(remaining_projections); @@ -315,24 +251,24 @@ fn strip_prefix<'tcx>( } impl<'tcx> PlaceBuilder<'tcx> { - pub(crate) fn into_place<'a>( + pub(in crate::build) fn into_place<'a>( self, tcx: TyCtxt<'tcx>, - typeck_results: &'a ty::TypeckResults<'tcx>, + upvars: &'a CaptureMap<'tcx>, ) -> Place<'tcx> { if let PlaceBase::Local(local) = self.base { Place { local, projection: tcx.intern_place_elems(&self.projection) } } else { - self.expect_upvars_resolved(tcx, typeck_results).into_place(tcx, typeck_results) + self.expect_upvars_resolved(tcx, upvars).into_place(tcx, upvars) } } fn expect_upvars_resolved<'a>( self, tcx: TyCtxt<'tcx>, - typeck_results: &'a ty::TypeckResults<'tcx>, + upvars: &'a CaptureMap<'tcx>, ) -> PlaceBuilder<'tcx> { - to_upvars_resolved_place_builder(self, tcx, typeck_results).unwrap() + to_upvars_resolved_place_builder(self, tcx, upvars).unwrap() } /// Attempts to resolve the `PlaceBuilder`. @@ -346,12 +282,12 @@ impl<'tcx> PlaceBuilder<'tcx> { /// not captured. This can happen because the final mir that will be /// generated doesn't require a read for this place. Failures will only /// happen inside closures. - pub(crate) fn try_upvars_resolved<'a>( + pub(in crate::build) fn try_upvars_resolved<'a>( self, tcx: TyCtxt<'tcx>, - typeck_results: &'a ty::TypeckResults<'tcx>, + upvars: &'a CaptureMap<'tcx>, ) -> Result, PlaceBuilder<'tcx>> { - to_upvars_resolved_place_builder(self, tcx, typeck_results) + to_upvars_resolved_place_builder(self, tcx, upvars) } pub(crate) fn base(&self) -> PlaceBase { @@ -392,6 +328,12 @@ impl<'tcx> From for PlaceBuilder<'tcx> { } } +impl<'tcx> From> for PlaceBuilder<'tcx> { + fn from(p: Place<'tcx>) -> Self { + Self { base: PlaceBase::Local(p.local), projection: p.projection.to_vec() } + } +} + impl<'a, 'tcx> Builder<'a, 'tcx> { /// Compile `expr`, yielding a place that we can move from etc. /// @@ -411,7 +353,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { expr: &Expr<'tcx>, ) -> BlockAnd> { let place_builder = unpack!(block = self.as_place_builder(block, expr)); - block.and(place_builder.into_place(self.tcx, self.typeck_results)) + block.and(place_builder.into_place(self.tcx, &self.upvars)) } /// This is used when constructing a compound `Place`, so that we can avoid creating @@ -435,7 +377,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { expr: &Expr<'tcx>, ) -> BlockAnd> { let place_builder = unpack!(block = self.as_read_only_place_builder(block, expr)); - block.and(place_builder.into_place(self.tcx, self.typeck_results)) + block.and(place_builder.into_place(self.tcx, &self.upvars)) } /// This is used when constructing a compound `Place`, so that we can avoid creating @@ -513,7 +455,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { block.and(place_builder) } - ExprKind::PlaceTypeAscription { source, user_ty } => { + ExprKind::PlaceTypeAscription { source, ref user_ty } => { let place_builder = unpack!( block = this.expr_as_place( block, @@ -526,11 +468,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let annotation_index = this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation { span: source_info.span, - user_ty, + user_ty: user_ty.clone(), inferred_ty: expr.ty, }); - let place = place_builder.clone().into_place(this.tcx, this.typeck_results); + let place = place_builder.clone().into_place(this.tcx, &this.upvars); this.cfg.push( block, Statement { @@ -547,7 +489,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { } block.and(place_builder) } - ExprKind::ValueTypeAscription { source, user_ty } => { + ExprKind::ValueTypeAscription { source, ref user_ty } => { let source = &this.thir[source]; let temp = unpack!(block = this.as_temp(block, source.temp_lifetime, source, mutability)); @@ -555,7 +497,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let annotation_index = this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation { span: source_info.span, - user_ty, + user_ty: user_ty.clone(), inferred_ty: expr.ty, }); this.cfg.push( @@ -629,17 +571,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { closure_def_id: LocalDefId, var_hir_id: LocalVarId, ) -> BlockAnd> { - let closure_ty = - self.typeck_results.node_type(self.tcx.hir().local_def_id_to_hir_id(closure_def_id)); - - let closure_kind = if let ty::Closure(_, closure_substs) = closure_ty.kind() { - self.infcx.closure_kind(closure_substs).unwrap() - } else { - // Generators are considered FnOnce. - ty::ClosureKind::FnOnce - }; - - block.and(PlaceBuilder::from(PlaceBase::Upvar { var_hir_id, closure_def_id, closure_kind })) + block.and(PlaceBuilder::from(PlaceBase::Upvar { var_hir_id, closure_def_id })) } /// Lower an index expression @@ -678,7 +610,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { if is_outermost_index { self.read_fake_borrows(block, fake_borrow_temps, source_info) } else { - base_place = base_place.expect_upvars_resolved(self.tcx, self.typeck_results); + base_place = base_place.expect_upvars_resolved(self.tcx, &self.upvars); self.add_fake_borrows_of_base( &base_place, block, @@ -710,7 +642,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { block, source_info, len, - Rvalue::Len(slice.into_place(self.tcx, self.typeck_results)), + Rvalue::Len(slice.into_place(self.tcx, &self.upvars)), ); // lt = idx < len self.cfg.push_assign( diff --git a/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs b/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs index 15f2d17c4..f88ab63f0 100644 --- a/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs +++ b/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs @@ -197,13 +197,13 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // create all the steps directly in MIR with operations all backends need to support anyway. let (source, ty) = if let ty::Adt(adt_def, ..) = source.ty.kind() && adt_def.is_enum() { let discr_ty = adt_def.repr().discr_type().to_ty(this.tcx); - let place = unpack!(block = this.as_place(block, source)); + let temp = unpack!(block = this.as_temp(block, scope, source, Mutability::Not)); let discr = this.temp(discr_ty, source.span); this.cfg.push_assign( block, source_info, discr, - Rvalue::Discriminant(place), + Rvalue::Discriminant(temp.into()), ); (Operand::Move(discr), discr_ty) @@ -216,6 +216,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { }; let from_ty = CastTy::from_ty(ty); let cast_ty = CastTy::from_ty(expr.ty); + debug!("ExprKind::Cast from_ty={from_ty:?}, cast_ty={:?}/{cast_ty:?}", expr.ty,); let cast_kind = match (from_ty, cast_ty) { (Some(CastTy::Ptr(_) | CastTy::FnPtr), Some(CastTy::Int(_))) => { CastKind::PointerExposeAddress @@ -223,6 +224,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { (Some(CastTy::Int(_)), Some(CastTy::Ptr(_))) => { CastKind::PointerFromExposedAddress } + (_, Some(CastTy::DynStar)) => CastKind::DynStar, (_, _) => CastKind::Misc, }; block.and(Rvalue::Cast(cast_kind, source, expr.ty)) @@ -302,7 +304,13 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { block.and(Rvalue::Aggregate(Box::new(AggregateKind::Tuple), fields)) } - ExprKind::Closure { closure_id, substs, ref upvars, movability, ref fake_reads } => { + ExprKind::Closure(box ClosureExpr { + closure_id, + substs, + ref upvars, + movability, + ref fake_reads, + }) => { // Convert the closure fake reads, if any, from `ExprRef` to mir `Place` // and push the fake reads. // This must come before creating the operands. This is required in case @@ -322,10 +330,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { unpack!(block = this.as_place_builder(block, &this.thir[*thir_place])); if let Ok(place_builder_resolved) = - place_builder.try_upvars_resolved(this.tcx, this.typeck_results) + place_builder.try_upvars_resolved(this.tcx, &this.upvars) { - let mir_place = - place_builder_resolved.into_place(this.tcx, this.typeck_results); + let mir_place = place_builder_resolved.into_place(this.tcx, &this.upvars); this.cfg.push_fake_read( block, this.source_info(this.tcx.hir().span(*hir_id)), @@ -617,7 +624,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // is same as that of the capture in the parent closure. PlaceBase::Upvar { .. } => { let enclosing_upvars_resolved = - arg_place_builder.clone().into_place(this.tcx, this.typeck_results); + arg_place_builder.clone().into_place(this.tcx, &this.upvars); match enclosing_upvars_resolved.as_ref() { PlaceRef { @@ -637,12 +644,12 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { ); // Not in a closure debug_assert!( - this.upvar_mutbls.len() > upvar_index.index(), - "Unexpected capture place, upvar_mutbls={:#?}, upvar_index={:?}", - this.upvar_mutbls, + this.upvars.len() > upvar_index.index(), + "Unexpected capture place, upvars={:#?}, upvar_index={:?}", + this.upvars, upvar_index ); - this.upvar_mutbls[upvar_index.index()] + this.upvars[upvar_index.index()].mutability } _ => bug!("Unexpected capture place"), } @@ -654,7 +661,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { Mutability::Mut => BorrowKind::Mut { allow_two_phase_borrow: false }, }; - let arg_place = arg_place_builder.into_place(this.tcx, this.typeck_results); + let arg_place = arg_place_builder.into_place(this.tcx, &this.upvars); this.cfg.push_assign( block, diff --git a/compiler/rustc_mir_build/src/build/expr/as_temp.rs b/compiler/rustc_mir_build/src/build/expr/as_temp.rs index 724b72f87..e5dafb820 100644 --- a/compiler/rustc_mir_build/src/build/expr/as_temp.rs +++ b/compiler/rustc_mir_build/src/build/expr/as_temp.rs @@ -83,8 +83,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // Don't bother with StorageLive and Dead for these temporaries, // they are never assigned. ExprKind::Break { .. } | ExprKind::Continue { .. } | ExprKind::Return { .. } => (), - ExprKind::Block { body: Block { expr: None, targeted_by_break: false, .. } } - if expr_ty.is_never() => {} + ExprKind::Block { block } + if let Block { expr: None, targeted_by_break: false, .. } = this.thir[block] + && expr_ty.is_never() => {} _ => { this.cfg .push(block, Statement { source_info, kind: StatementKind::StorageLive(temp) }); diff --git a/compiler/rustc_mir_build/src/build/expr/into.rs b/compiler/rustc_mir_build/src/build/expr/into.rs index 017d43d10..224a1b80f 100644 --- a/compiler/rustc_mir_build/src/build/expr/into.rs +++ b/compiler/rustc_mir_build/src/build/expr/into.rs @@ -46,7 +46,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { }) }) } - ExprKind::Block { body: ref ast_block } => { + ExprKind::Block { block: ast_block } => { this.ast_block(destination, block, ast_block, source_info) } ExprKind::Match { scrutinee, ref arms } => { @@ -75,7 +75,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { this.source_info(then_expr.span) }; let (then_block, else_block) = - this.in_if_then_scope(condition_scope, |this| { + this.in_if_then_scope(condition_scope, then_expr.span, |this| { let then_blk = unpack!(this.then_else_break( block, &this.thir[cond], @@ -108,7 +108,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { } ExprKind::Let { expr, ref pat } => { let scope = this.local_scope(); - let (true_block, false_block) = this.in_if_then_scope(scope, |this| { + let (true_block, false_block) = this.in_if_then_scope(scope, expr_span, |this| { this.lower_let_expr(block, &this.thir[expr], pat, scope, None, expr_span) }); @@ -314,11 +314,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { this.cfg.push_assign(block, source_info, destination, address_of); block.unit() } - ExprKind::Adt(box Adt { + ExprKind::Adt(box AdtExpr { adt_def, variant_index, substs, - user_ty, + ref user_ty, ref fields, ref base, }) => { @@ -366,9 +366,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { None => { let place_builder = place_builder.clone(); this.consume_by_copy_or_move( - place_builder - .field(n, *ty) - .into_place(this.tcx, this.typeck_results), + place_builder.field(n, *ty).into_place(this.tcx, &this.upvars), ) } }) @@ -378,10 +376,10 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { }; let inferred_ty = expr.ty; - let user_ty = user_ty.map(|ty| { + let user_ty = user_ty.as_ref().map(|user_ty| { this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation { span: source_info.span, - user_ty: ty, + user_ty: user_ty.clone(), inferred_ty, }) }); @@ -400,7 +398,12 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { ); block.unit() } - ExprKind::InlineAsm { template, ref operands, options, line_spans } => { + ExprKind::InlineAsm(box InlineAsmExpr { + template, + ref operands, + options, + line_spans, + }) => { use rustc_middle::{mir, thir}; let operands = operands .into_iter() diff --git a/compiler/rustc_mir_build/src/build/expr/stmt.rs b/compiler/rustc_mir_build/src/build/expr/stmt.rs index a7e1331aa..00dbcaeb0 100644 --- a/compiler/rustc_mir_build/src/build/expr/stmt.rs +++ b/compiler/rustc_mir_build/src/build/expr/stmt.rs @@ -116,14 +116,22 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // it is usually better to focus on `the_value` rather // than the entirety of block(s) surrounding it. let adjusted_span = (|| { - if let ExprKind::Block { body } = &expr.kind && let Some(tail_ex) = body.expr { + if let ExprKind::Block { block } = expr.kind + && let Some(tail_ex) = this.thir[block].expr + { let mut expr = &this.thir[tail_ex]; - while let ExprKind::Block { - body: Block { expr: Some(nested_expr), .. }, - } - | ExprKind::Scope { value: nested_expr, .. } = expr.kind - { - expr = &this.thir[nested_expr]; + loop { + match expr.kind { + ExprKind::Block { block } + if let Some(nested_expr) = this.thir[block].expr => + { + expr = &this.thir[nested_expr]; + } + ExprKind::Scope { value: nested_expr, .. } => { + expr = &this.thir[nested_expr]; + } + _ => break, + } } this.block_context.push(BlockFrame::TailExpr { tail_result_is_ignored: true, diff --git a/compiler/rustc_mir_build/src/build/matches/mod.rs b/compiler/rustc_mir_build/src/build/matches/mod.rs index 58b1564cc..93f382cc6 100644 --- a/compiler/rustc_mir_build/src/build/matches/mod.rs +++ b/compiler/rustc_mir_build/src/build/matches/mod.rs @@ -155,7 +155,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { /// /// * From each pre-binding block to the next pre-binding block. /// * From each otherwise block to the next pre-binding block. - #[tracing::instrument(level = "debug", skip(self, arms))] + #[instrument(level = "debug", skip(self, arms))] pub(crate) fn match_expr( &mut self, destination: Place<'tcx>, @@ -170,7 +170,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let mut arm_candidates = self.create_match_candidates(scrutinee_place.clone(), &arms); - let match_has_guard = arms.iter().copied().any(|arm| self.thir[arm].guard.is_some()); + let match_has_guard = arm_candidates.iter().any(|(_, candidate)| candidate.has_guard); let mut candidates = arm_candidates.iter_mut().map(|(_, candidate)| candidate).collect::>(); @@ -221,9 +221,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let source_info = self.source_info(scrutinee_span); if let Ok(scrutinee_builder) = - scrutinee_place_builder.clone().try_upvars_resolved(self.tcx, self.typeck_results) + scrutinee_place_builder.clone().try_upvars_resolved(self.tcx, &self.upvars) { - let scrutinee_place = scrutinee_builder.into_place(self.tcx, self.typeck_results); + let scrutinee_place = scrutinee_builder.into_place(self.tcx, &self.upvars); self.cfg.push_fake_read(block, source_info, cause_matched_place, scrutinee_place); } @@ -348,12 +348,10 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // ``` let mut opt_scrutinee_place: Option<(Option<&Place<'tcx>>, Span)> = None; let scrutinee_place: Place<'tcx>; - if let Ok(scrutinee_builder) = scrutinee_place_builder - .clone() - .try_upvars_resolved(this.tcx, this.typeck_results) + if let Ok(scrutinee_builder) = + scrutinee_place_builder.clone().try_upvars_resolved(this.tcx, &this.upvars) { - scrutinee_place = - scrutinee_builder.into_place(this.tcx, this.typeck_results); + scrutinee_place = scrutinee_builder.into_place(this.tcx, &this.upvars); opt_scrutinee_place = Some((Some(&scrutinee_place), scrutinee_span)); } let scope = this.declare_bindings( @@ -373,6 +371,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { Some(arm.span), Some(arm.scope), Some(match_scope), + false, ); if let Some(source_scope) = scope { @@ -418,6 +417,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { arm_span: Option, arm_scope: Option, match_scope: Option, + storages_alive: bool, ) -> BasicBlock { if candidate.subcandidates.is_empty() { // Avoid generating another `BasicBlock` when we only have one @@ -431,6 +431,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { arm_span, match_scope, true, + storages_alive, ) } else { // It's helpful to avoid scheduling drops multiple times to save @@ -468,6 +469,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { arm_span, match_scope, schedule_drops, + storages_alive, ); if arm_scope.is_none() { schedule_drops = false; @@ -490,10 +492,10 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { pub(super) fn expr_into_pattern( &mut self, mut block: BasicBlock, - irrefutable_pat: Pat<'tcx>, + irrefutable_pat: &Pat<'tcx>, initializer: &Expr<'tcx>, ) -> BlockAnd<()> { - match *irrefutable_pat.kind { + match irrefutable_pat.kind { // Optimize the case of `let x = ...` to write directly into `x` PatKind::Binding { mode: BindingMode::ByValue, var, subpattern: None, .. } => { let place = @@ -518,17 +520,14 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // broken. PatKind::AscribeUserType { subpattern: - Pat { + box Pat { kind: - box PatKind::Binding { - mode: BindingMode::ByValue, - var, - subpattern: None, - .. + PatKind::Binding { + mode: BindingMode::ByValue, var, subpattern: None, .. }, .. }, - ascription: thir::Ascription { annotation, variance: _ }, + ascription: thir::Ascription { ref annotation, variance: _ }, } => { let place = self.storage_live_binding(block, var, irrefutable_pat.span, OutsideGuard, true); @@ -541,7 +540,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let ty_source_info = self.source_info(annotation.span); - let base = self.canonical_user_type_annotations.push(annotation); + let base = self.canonical_user_type_annotations.push(annotation.clone()); self.cfg.push( block, Statement { @@ -573,7 +572,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { _ => { let place_builder = unpack!(block = self.as_place_builder(block, initializer)); - self.place_into_pattern(block, irrefutable_pat, place_builder, true) + self.place_into_pattern(block, &irrefutable_pat, place_builder, true) } } } @@ -581,7 +580,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { pub(crate) fn place_into_pattern( &mut self, block: BasicBlock, - irrefutable_pat: Pat<'tcx>, + irrefutable_pat: &Pat<'tcx>, initializer: PlaceBuilder<'tcx>, set_match_place: bool, ) -> BlockAnd<()> { @@ -623,9 +622,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // }; // ``` if let Ok(match_pair_resolved) = - initializer.clone().try_upvars_resolved(self.tcx, self.typeck_results) + initializer.clone().try_upvars_resolved(self.tcx, &self.upvars) { - let place = match_pair_resolved.into_place(self.tcx, self.typeck_results); + let place = match_pair_resolved.into_place(self.tcx, &self.upvars); *match_place = Some(place); } } @@ -646,6 +645,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { None, None, None, + false, ) .unit() } @@ -702,9 +702,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let local_id = self.var_local_id(var, for_guard); let source_info = self.source_info(span); self.cfg.push(block, Statement { source_info, kind: StatementKind::StorageLive(local_id) }); - // Altough there is almost always scope for given variable in corner cases + // Although there is almost always scope for given variable in corner cases // like #92893 we might get variable with no scope. - if let Some(region_scope) = self.region_scope_tree.var_scope(var.0.local_id) && schedule_drop{ + if let Some(region_scope) = self.region_scope_tree.var_scope(var.0.local_id) && schedule_drop { self.schedule_drop(span, region_scope, local_id, DropKind::Storage); } Place::from(local_id) @@ -744,7 +744,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { "visit_primary_bindings: pattern={:?} pattern_user_ty={:?}", pattern, pattern_user_ty ); - match *pattern.kind { + match pattern.kind { PatKind::Binding { mutability, name, @@ -767,7 +767,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { | PatKind::Slice { ref prefix, ref slice, ref suffix } => { let from = u64::try_from(prefix.len()).unwrap(); let to = u64::try_from(suffix.len()).unwrap(); - for subpattern in prefix { + for subpattern in prefix.iter() { self.visit_primary_bindings(subpattern, pattern_user_ty.clone().index(), f); } for subpattern in slice { @@ -777,7 +777,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { f, ); } - for subpattern in suffix { + for subpattern in suffix.iter() { self.visit_primary_bindings(subpattern, pattern_user_ty.clone().index(), f); } } @@ -830,7 +830,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // may not all be in the leftmost subpattern. For example in // `let (x | y) = ...`, the primary binding of `y` occurs in // the right subpattern - for subpattern in pats { + for subpattern in pats.iter() { self.visit_primary_bindings(subpattern, pattern_user_ty.clone(), f); } } @@ -982,7 +982,7 @@ enum TestKind<'tcx> { }, /// Test whether the value falls within an inclusive or exclusive range - Range(PatRange<'tcx>), + Range(Box>), /// Test that the length of the slice is equal to `len`. Len { len: u64, op: BinOp }, @@ -1330,7 +1330,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // All of the or-patterns have been sorted to the end, so if the first // pattern is an or-pattern we only have or-patterns. - match *first_candidate.match_pairs[0].pattern.kind { + match first_candidate.match_pairs[0].pattern.kind { PatKind::Or { .. } => (), _ => { self.test_candidates( @@ -1350,7 +1350,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let mut otherwise = None; for match_pair in match_pairs { - let PatKind::Or { ref pats } = &*match_pair.pattern.kind else { + let PatKind::Or { ref pats } = &match_pair.pattern.kind else { bug!("Or-patterns should have been sorted to the end"); }; let or_span = match_pair.pattern.span; @@ -1384,7 +1384,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { &mut self, candidate: &mut Candidate<'pat, 'tcx>, otherwise: &mut Option, - pats: &'pat [Pat<'tcx>], + pats: &'pat [Box>], or_span: Span, place: PlaceBuilder<'tcx>, fake_borrows: &mut Option>>, @@ -1605,9 +1605,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // Insert a Shallow borrow of any places that is switched on. if let Some(fb) = fake_borrows && let Ok(match_place_resolved) = - match_place.clone().try_upvars_resolved(self.tcx, self.typeck_results) + match_place.clone().try_upvars_resolved(self.tcx, &self.upvars) { - let resolved_place = match_place_resolved.into_place(self.tcx, self.typeck_results); + let resolved_place = match_place_resolved.into_place(self.tcx, &self.upvars); fb.insert(resolved_place); } @@ -1794,10 +1794,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { ); let mut opt_expr_place: Option<(Option<&Place<'tcx>>, Span)> = None; let expr_place: Place<'tcx>; - if let Ok(expr_builder) = - expr_place_builder.try_upvars_resolved(self.tcx, self.typeck_results) - { - expr_place = expr_builder.into_place(self.tcx, self.typeck_results); + if let Ok(expr_builder) = expr_place_builder.try_upvars_resolved(self.tcx, &self.upvars) { + expr_place = expr_builder.into_place(self.tcx, &self.upvars); opt_expr_place = Some((Some(&expr_place), expr_span)); } let otherwise_post_guard_block = otherwise_candidate.pre_binding_block.unwrap(); @@ -1820,6 +1818,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { None, None, None, + false, ); post_guard_block.unit() @@ -1843,6 +1842,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { arm_span: Option, match_scope: Option, schedule_drops: bool, + storages_alive: bool, ) -> BasicBlock { debug!("bind_and_guard_matched_candidate(candidate={:?})", candidate); @@ -1978,7 +1978,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let mut guard_span = rustc_span::DUMMY_SP; let (post_guard_block, otherwise_post_guard_block) = - self.in_if_then_scope(match_scope, |this| match *guard { + self.in_if_then_scope(match_scope, guard_span, |this| match *guard { Guard::If(e) => { let e = &this.thir[e]; guard_span = e.span; @@ -2058,7 +2058,12 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { self.cfg.push_fake_read(post_guard_block, guard_end, cause, Place::from(local_id)); } assert!(schedule_drops, "patterns with guards must schedule drops"); - self.bind_matched_candidate_for_arm_body(post_guard_block, true, by_value_bindings); + self.bind_matched_candidate_for_arm_body( + post_guard_block, + true, + by_value_bindings, + storages_alive, + ); post_guard_block } else { @@ -2072,6 +2077,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { .iter() .flat_map(|(bindings, _)| bindings) .chain(&candidate.bindings), + storages_alive, ); block } @@ -2161,6 +2167,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { block: BasicBlock, schedule_drops: bool, bindings: impl IntoIterator>, + storages_alive: bool, ) where 'tcx: 'b, { @@ -2170,13 +2177,20 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // Assign each of the bindings. This may trigger moves out of the candidate. for binding in bindings { let source_info = self.source_info(binding.span); - let local = self.storage_live_binding( - block, - binding.var_id, - binding.span, - OutsideGuard, - schedule_drops, - ); + let local = if storages_alive { + // Here storages are already alive, probably because this is a binding + // from let-else. + // We just need to schedule drop for the value. + self.var_local_id(binding.var_id, OutsideGuard).into() + } else { + self.storage_live_binding( + block, + binding.var_id, + binding.span, + OutsideGuard, + schedule_drops, + ) + }; if schedule_drops { self.schedule_drop_for_binding(binding.var_id, binding.span, OutsideGuard); } @@ -2280,23 +2294,15 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { mut block: BasicBlock, init: &Expr<'tcx>, initializer_span: Span, - else_block: &Block, - visibility_scope: Option, - remainder_scope: region::Scope, - remainder_span: Span, + else_block: BlockId, + let_else_scope: ®ion::Scope, pattern: &Pat<'tcx>, - ) -> BlockAnd<()> { - let (matching, failure) = self.in_if_then_scope(remainder_scope, |this| { + ) -> BlockAnd { + let else_block_span = self.thir[else_block].span; + let (matching, failure) = self.in_if_then_scope(*let_else_scope, else_block_span, |this| { let scrutinee = unpack!(block = this.lower_scrutinee(block, init, initializer_span)); - let pat = Pat { ty: init.ty, span: else_block.span, kind: Box::new(PatKind::Wild) }; + let pat = Pat { ty: init.ty, span: else_block_span, kind: PatKind::Wild }; let mut wildcard = Candidate::new(scrutinee.clone(), &pat, false); - this.declare_bindings( - visibility_scope, - remainder_span, - pattern, - ArmHasGuard(false), - Some((None, initializer_span)), - ); let mut candidate = Candidate::new(scrutinee.clone(), pattern, false); let fake_borrow_temps = this.lower_match_tree( block, @@ -2315,10 +2321,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { None, None, None, + true, ); // This block is for the failure case let failure = this.bind_pattern( - this.source_info(else_block.span), + this.source_info(else_block_span), wildcard, None, &fake_borrow_temps, @@ -2326,29 +2333,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { None, None, None, + true, ); - this.break_for_else(failure, remainder_scope, this.source_info(initializer_span)); + this.break_for_else(failure, *let_else_scope, this.source_info(initializer_span)); matching.unit() }); - - // This place is not really used because this destination place - // should never be used to take values at the end of the failure - // block. - let dummy_place = Place { local: RETURN_PLACE, projection: ty::List::empty() }; - let failure_block; - unpack!( - failure_block = self.ast_block( - dummy_place, - failure, - else_block, - self.source_info(else_block.span), - ) - ); - self.cfg.terminate( - failure_block, - self.source_info(else_block.span), - TerminatorKind::Unreachable, - ); - matching.unit() + matching.and(failure) } } diff --git a/compiler/rustc_mir_build/src/build/matches/simplify.rs b/compiler/rustc_mir_build/src/build/matches/simplify.rs index c62989041..df221d356 100644 --- a/compiler/rustc_mir_build/src/build/matches/simplify.rs +++ b/compiler/rustc_mir_build/src/build/matches/simplify.rs @@ -67,7 +67,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { loop { let match_pairs = mem::take(&mut candidate.match_pairs); - if let [MatchPair { pattern: Pat { kind: box PatKind::Or { pats }, .. }, place }] = + if let [MatchPair { pattern: Pat { kind: PatKind::Or { pats }, .. }, place }] = &*match_pairs { existing_bindings.extend_from_slice(&new_bindings); @@ -113,7 +113,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // late as possible. candidate .match_pairs - .sort_by_key(|pair| matches!(*pair.pattern.kind, PatKind::Or { .. })); + .sort_by_key(|pair| matches!(pair.pattern.kind, PatKind::Or { .. })); debug!(simplified = ?candidate, "simplify_candidate"); return false; // if we were not able to simplify any, done. } @@ -127,10 +127,10 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { &mut self, candidate: &Candidate<'pat, 'tcx>, place: PlaceBuilder<'tcx>, - pats: &'pat [Pat<'tcx>], + pats: &'pat [Box>], ) -> Vec> { pats.iter() - .map(|pat| { + .map(|box pat| { let mut candidate = Candidate::new(place.clone(), pat, candidate.has_guard); self.simplify_candidate(&mut candidate); candidate @@ -149,18 +149,18 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { candidate: &mut Candidate<'pat, 'tcx>, ) -> Result<(), MatchPair<'pat, 'tcx>> { let tcx = self.tcx; - match *match_pair.pattern.kind { + match match_pair.pattern.kind { PatKind::AscribeUserType { ref subpattern, ascription: thir::Ascription { ref annotation, variance }, } => { // Apply the type ascription to the value at `match_pair.place`, which is the if let Ok(place_resolved) = - match_pair.place.clone().try_upvars_resolved(self.tcx, self.typeck_results) + match_pair.place.clone().try_upvars_resolved(self.tcx, &self.upvars) { candidate.ascriptions.push(Ascription { annotation: annotation.clone(), - source: place_resolved.into_place(self.tcx, self.typeck_results), + source: place_resolved.into_place(self.tcx, &self.upvars), variance, }); } @@ -185,11 +185,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { is_primary: _, } => { if let Ok(place_resolved) = - match_pair.place.clone().try_upvars_resolved(self.tcx, self.typeck_results) + match_pair.place.clone().try_upvars_resolved(self.tcx, &self.upvars) { candidate.bindings.push(Binding { span: match_pair.pattern.span, - source: place_resolved.into_place(self.tcx, self.typeck_results), + source: place_resolved.into_place(self.tcx, &self.upvars), var_id: var, binding_mode: mode, }); @@ -208,7 +208,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { Err(match_pair) } - PatKind::Range(PatRange { lo, hi, end }) => { + PatKind::Range(box PatRange { lo, hi, end }) => { let (range, bias) = match *lo.ty().kind() { ty::Char => { (Some(('\u{0000}' as u128, '\u{10FFFF}' as u128, Size::from_bits(32))), 0) @@ -254,7 +254,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { &mut candidate.match_pairs, &match_pair.place, prefix, - slice.as_ref(), + slice, suffix, ); Ok(()) @@ -294,7 +294,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { &mut candidate.match_pairs, &match_pair.place, prefix, - slice.as_ref(), + slice, suffix, ); Ok(()) diff --git a/compiler/rustc_mir_build/src/build/matches/test.rs b/compiler/rustc_mir_build/src/build/matches/test.rs index 598da80c5..47d05a6e3 100644 --- a/compiler/rustc_mir_build/src/build/matches/test.rs +++ b/compiler/rustc_mir_build/src/build/matches/test.rs @@ -29,7 +29,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { /// /// It is a bug to call this with a not-fully-simplified pattern. pub(super) fn test<'pat>(&mut self, match_pair: &MatchPair<'pat, 'tcx>) -> Test<'tcx> { - match *match_pair.pattern.kind { + match match_pair.pattern.kind { PatKind::Variant { adt_def, substs: _, variant_index: _, subpatterns: _ } => Test { span: match_pair.pattern.span, kind: TestKind::Switch { @@ -58,10 +58,10 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { kind: TestKind::Eq { value, ty: match_pair.pattern.ty }, }, - PatKind::Range(range) => { + PatKind::Range(ref range) => { assert_eq!(range.lo.ty(), match_pair.pattern.ty); assert_eq!(range.hi.ty(), match_pair.pattern.ty); - Test { span: match_pair.pattern.span, kind: TestKind::Range(range) } + Test { span: match_pair.pattern.span, kind: TestKind::Range(range.clone()) } } PatKind::Slice { ref prefix, ref slice, ref suffix } => { @@ -92,7 +92,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { return false; }; - match *match_pair.pattern.kind { + match match_pair.pattern.kind { PatKind::Constant { value } => { options .entry(value) @@ -102,9 +102,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { PatKind::Variant { .. } => { panic!("you should have called add_variants_to_switch instead!"); } - PatKind::Range(range) => { + PatKind::Range(ref range) => { // Check that none of the switch values are in the range. - self.values_not_contained_in_range(range, options).unwrap_or(false) + self.values_not_contained_in_range(&*range, options).unwrap_or(false) } PatKind::Slice { .. } | PatKind::Array { .. } @@ -130,7 +130,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { return false; }; - match *match_pair.pattern.kind { + match match_pair.pattern.kind { PatKind::Variant { adt_def: _, variant_index, .. } => { // We have a pattern testing for variant `variant_index` // set the corresponding index to true @@ -154,10 +154,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { make_target_blocks: impl FnOnce(&mut Self) -> Vec, ) { let place: Place<'tcx>; - if let Ok(test_place_builder) = - place_builder.try_upvars_resolved(self.tcx, self.typeck_results) - { - place = test_place_builder.into_place(self.tcx, self.typeck_results); + if let Ok(test_place_builder) = place_builder.try_upvars_resolved(self.tcx, &self.upvars) { + place = test_place_builder.into_place(self.tcx, &self.upvars); } else { return; } @@ -272,7 +270,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { } } - TestKind::Range(PatRange { lo, hi, ref end }) => { + TestKind::Range(box PatRange { lo, hi, ref end }) => { let lower_bound_success = self.cfg.start_new_block(); let target_blocks = make_target_blocks(self); @@ -506,7 +504,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let (match_pair_index, match_pair) = candidate.match_pairs.iter().enumerate().find(|&(_, mp)| mp.place == *test_place)?; - match (&test.kind, &*match_pair.pattern.kind) { + match (&test.kind, &match_pair.pattern.kind) { // If we are performing a variant switch, then this // informs variant patterns, but nothing else. ( @@ -540,9 +538,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { Some(index) } - (&TestKind::SwitchInt { switch_ty: _, ref options }, &PatKind::Range(range)) => { + (&TestKind::SwitchInt { switch_ty: _, ref options }, &PatKind::Range(ref range)) => { let not_contained = - self.values_not_contained_in_range(range, options).unwrap_or(false); + self.values_not_contained_in_range(&*range, options).unwrap_or(false); if not_contained { // No switch values are contained in the pattern range, @@ -569,7 +567,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { match_pair_index, candidate, prefix, - slice.as_ref(), + slice, suffix, ); Some(0) @@ -607,7 +605,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { match_pair_index, candidate, prefix, - slice.as_ref(), + slice, suffix, ); Some(0) @@ -631,7 +629,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { } } - (&TestKind::Range(test), &PatKind::Range(pat)) => { + (&TestKind::Range(ref test), &PatKind::Range(ref pat)) => { use std::cmp::Ordering::*; if test == pat { @@ -658,8 +656,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { no_overlap } - (&TestKind::Range(range), &PatKind::Constant { value }) => { - if let Some(false) = self.const_range_contains(range, value) { + (&TestKind::Range(ref range), &PatKind::Constant { value }) => { + if let Some(false) = self.const_range_contains(&*range, value) { // `value` is not contained in the testing range, // so `value` can be matched only if this test fails. Some(1) @@ -678,7 +676,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // However, at this point we can still encounter or-patterns that were extracted // from previous calls to `sort_candidate`, so we need to manually address that // case to avoid panicking in `self.test()`. - if let PatKind::Or { .. } = &*match_pair.pattern.kind { + if let PatKind::Or { .. } = &match_pair.pattern.kind { return None; } @@ -708,9 +706,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { &mut self, match_pair_index: usize, candidate: &mut Candidate<'pat, 'tcx>, - prefix: &'pat [Pat<'tcx>], - opt_slice: Option<&'pat Pat<'tcx>>, - suffix: &'pat [Pat<'tcx>], + prefix: &'pat [Box>], + opt_slice: &'pat Option>>, + suffix: &'pat [Box>], ) { let removed_place = candidate.match_pairs.remove(match_pair_index).place; self.prefix_slice_suffix( @@ -754,7 +752,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { fn const_range_contains( &self, - range: PatRange<'tcx>, + range: &PatRange<'tcx>, value: ConstantKind<'tcx>, ) -> Option { use std::cmp::Ordering::*; @@ -772,7 +770,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { fn values_not_contained_in_range( &self, - range: PatRange<'tcx>, + range: &PatRange<'tcx>, options: &FxIndexMap, u128>, ) -> Option { for &val in options.keys() { diff --git a/compiler/rustc_mir_build/src/build/matches/util.rs b/compiler/rustc_mir_build/src/build/matches/util.rs index 9a1e98d3b..b61c4fe50 100644 --- a/compiler/rustc_mir_build/src/build/matches/util.rs +++ b/compiler/rustc_mir_build/src/build/matches/util.rs @@ -26,19 +26,15 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { &mut self, match_pairs: &mut SmallVec<[MatchPair<'pat, 'tcx>; 1]>, place: &PlaceBuilder<'tcx>, - prefix: &'pat [Pat<'tcx>], - opt_slice: Option<&'pat Pat<'tcx>>, - suffix: &'pat [Pat<'tcx>], + prefix: &'pat [Box>], + opt_slice: &'pat Option>>, + suffix: &'pat [Box>], ) { let tcx = self.tcx; let (min_length, exact_size) = if let Ok(place_resolved) = - place.clone().try_upvars_resolved(tcx, self.typeck_results) + place.clone().try_upvars_resolved(tcx, &self.upvars) { - match place_resolved - .into_place(tcx, self.typeck_results) - .ty(&self.local_decls, tcx) - .ty - .kind() + match place_resolved.into_place(tcx, &self.upvars).ty(&self.local_decls, tcx).ty.kind() { ty::Array(_, length) => (length.eval_usize(tcx, self.param_env), true), _ => ((prefix.len() + suffix.len()).try_into().unwrap(), false), diff --git a/compiler/rustc_mir_build/src/build/mod.rs b/compiler/rustc_mir_build/src/build/mod.rs index 12b8ceede..25c4e51cb 100644 --- a/compiler/rustc_mir_build/src/build/mod.rs +++ b/compiler/rustc_mir_build/src/build/mod.rs @@ -1,15 +1,14 @@ -use crate::build; pub(crate) use crate::build::expr::as_constant::lit_to_mir_constant; use crate::build::expr::as_place::PlaceBuilder; use crate::build::scope::DropKind; -use crate::thir::pattern::pat_from_hir; use rustc_apfloat::ieee::{Double, Single}; use rustc_apfloat::Float; use rustc_data_structures::fx::FxHashMap; +use rustc_data_structures::sorted_map::SortedIndexMultiMap; use rustc_errors::ErrorGuaranteed; use rustc_hir as hir; +use rustc_hir::def::DefKind; use rustc_hir::def_id::{DefId, LocalDefId}; -use rustc_hir::lang_items::LangItem; use rustc_hir::{GeneratorKind, Node}; use rustc_index::vec::{Idx, IndexVec}; use rustc_infer::infer::{InferCtxt, TyCtxtInferExt}; @@ -18,8 +17,9 @@ use rustc_middle::middle::region; use rustc_middle::mir::interpret::ConstValue; use rustc_middle::mir::interpret::Scalar; use rustc_middle::mir::*; -use rustc_middle::thir::{BindingMode, Expr, ExprId, LintLevel, LocalVarId, PatKind, Thir}; -use rustc_middle::ty::subst::Subst; +use rustc_middle::thir::{ + self, BindingMode, Expr, ExprId, LintLevel, LocalVarId, Param, ParamId, PatKind, Thir, +}; use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitable, TypeckResults}; use rustc_span::symbol::sym; use rustc_span::Span; @@ -47,9 +47,7 @@ pub(crate) fn mir_built<'tcx>( /// Construct the MIR for a given `DefId`. fn mir_build(tcx: TyCtxt<'_>, def: ty::WithOptConstParam) -> Body<'_> { - let id = tcx.hir().local_def_id_to_hir_id(def.did); let body_owner_kind = tcx.hir().body_owner_kind(def.did); - let typeck_results = tcx.typeck_opt_const_arg(def); // Ensure unsafeck and abstract const building is ran before we steal the THIR. // We can't use `ensure()` for `thir_abstract_const` as it doesn't compute the query @@ -66,235 +64,42 @@ fn mir_build(tcx: TyCtxt<'_>, def: ty::WithOptConstParam) -> Body<'_ } } - // Figure out what primary body this item has. - let (body_id, return_ty_span, span_with_body) = match tcx.hir().get(id) { - Node::Expr(hir::Expr { - kind: hir::ExprKind::Closure(hir::Closure { fn_decl, body, .. }), - .. - }) => (*body, fn_decl.output.span(), None), - Node::Item(hir::Item { - kind: hir::ItemKind::Fn(hir::FnSig { decl, .. }, _, body_id), - span, - .. - }) - | Node::ImplItem(hir::ImplItem { - kind: hir::ImplItemKind::Fn(hir::FnSig { decl, .. }, body_id), - span, - .. - }) - | Node::TraitItem(hir::TraitItem { - kind: hir::TraitItemKind::Fn(hir::FnSig { decl, .. }, hir::TraitFn::Provided(body_id)), - span, - .. - }) => { - // Use the `Span` of the `Item/ImplItem/TraitItem` as the body span, - // since the def span of a function does not include the body - (*body_id, decl.output.span(), Some(*span)) - } - Node::Item(hir::Item { - kind: hir::ItemKind::Static(ty, _, body_id) | hir::ItemKind::Const(ty, body_id), - .. - }) - | Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Const(ty, body_id), .. }) - | Node::TraitItem(hir::TraitItem { - kind: hir::TraitItemKind::Const(ty, Some(body_id)), - .. - }) => (*body_id, ty.span, None), - Node::AnonConst(hir::AnonConst { body, hir_id, .. }) => { - (*body, tcx.hir().span(*hir_id), None) - } - - _ => span_bug!(tcx.hir().span(id), "can't build MIR for {:?}", def.did), - }; - - // If we don't have a specialized span for the body, just use the - // normal def span. - let span_with_body = span_with_body.unwrap_or_else(|| tcx.hir().span(id)); - - tcx.infer_ctxt().enter(|infcx| { - let body = if let Some(error_reported) = typeck_results.tainted_by_errors { - build::construct_error(&infcx, def, id, body_id, body_owner_kind, error_reported) - } else if body_owner_kind.is_fn_or_closure() { - // fetch the fully liberated fn signature (that is, all bound - // types/lifetimes replaced) - let fn_sig = typeck_results.liberated_fn_sigs()[id]; - let fn_def_id = tcx.hir().local_def_id(id); - - let safety = match fn_sig.unsafety { - hir::Unsafety::Normal => Safety::Safe, - hir::Unsafety::Unsafe => Safety::FnUnsafe, - }; - - let body = tcx.hir().body(body_id); - let (thir, expr) = tcx - .thir_body(def) - .unwrap_or_else(|_| (tcx.alloc_steal_thir(Thir::new()), ExprId::from_u32(0))); + let body = match tcx.thir_body(def) { + Err(error_reported) => construct_error(tcx, def.did, body_owner_kind, error_reported), + Ok((thir, expr)) => { // We ran all queries that depended on THIR at the beginning // of `mir_build`, so now we can steal it let thir = thir.steal(); - let ty = tcx.type_of(fn_def_id); - let mut abi = fn_sig.abi; - let implicit_argument = match ty.kind() { - ty::Closure(..) => { - // HACK(eddyb) Avoid having RustCall on closures, - // as it adds unnecessary (and wrong) auto-tupling. - abi = Abi::Rust; - vec![ArgInfo(liberated_closure_env_ty(tcx, id, body_id), None, None, None)] - } - ty::Generator(..) => { - let gen_ty = tcx.typeck_body(body_id).node_type(id); - - // The resume argument may be missing, in that case we need to provide it here. - // It will always be `()` in this case. - if body.params.is_empty() { - vec![ - ArgInfo(gen_ty, None, None, None), - ArgInfo(tcx.mk_unit(), None, None, None), - ] - } else { - vec![ArgInfo(gen_ty, None, None, None)] - } - } - _ => vec![], - }; - - let explicit_arguments = body.params.iter().enumerate().map(|(index, arg)| { - let owner_id = tcx.hir().body_owner(body_id); - let opt_ty_info; - let self_arg; - if let Some(ref fn_decl) = tcx.hir().fn_decl_by_hir_id(owner_id) { - opt_ty_info = fn_decl - .inputs - .get(index) - // Make sure that inferred closure args have no type span - .and_then(|ty| if arg.pat.span != ty.span { Some(ty.span) } else { None }); - self_arg = if index == 0 && fn_decl.implicit_self.has_implicit_self() { - match fn_decl.implicit_self { - hir::ImplicitSelfKind::Imm => Some(ImplicitSelfKind::Imm), - hir::ImplicitSelfKind::Mut => Some(ImplicitSelfKind::Mut), - hir::ImplicitSelfKind::ImmRef => Some(ImplicitSelfKind::ImmRef), - hir::ImplicitSelfKind::MutRef => Some(ImplicitSelfKind::MutRef), - _ => None, - } - } else { - None - }; - } else { - opt_ty_info = None; - self_arg = None; - } - - // C-variadic fns also have a `VaList` input that's not listed in `fn_sig` - // (as it's created inside the body itself, not passed in from outside). - let ty = if fn_sig.c_variadic && index == fn_sig.inputs().len() { - let va_list_did = tcx.require_lang_item(LangItem::VaList, Some(arg.span)); - - tcx.bound_type_of(va_list_did).subst(tcx, &[tcx.lifetimes.re_erased.into()]) - } else { - fn_sig.inputs()[index] - }; - - ArgInfo(ty, opt_ty_info, Some(&arg), self_arg) - }); - let arguments = implicit_argument.into_iter().chain(explicit_arguments); - - let (yield_ty, return_ty) = if body.generator_kind.is_some() { - let gen_ty = tcx.typeck_body(body_id).node_type(id); - let gen_sig = match gen_ty.kind() { - ty::Generator(_, gen_substs, ..) => gen_substs.as_generator().sig(), - _ => span_bug!(tcx.hir().span(id), "generator w/o generator type: {:?}", ty), - }; - (Some(gen_sig.yield_ty), gen_sig.return_ty) + if body_owner_kind.is_fn_or_closure() { + construct_fn(tcx, def, &thir, expr) } else { - (None, fn_sig.output()) - }; - - let mut mir = build::construct_fn( - &thir, - &infcx, - def, - id, - arguments, - safety, - abi, - return_ty, - return_ty_span, - body, - expr, - span_with_body, - ); - if yield_ty.is_some() { - mir.generator.as_mut().unwrap().yield_ty = yield_ty; + construct_const(tcx, def, &thir, expr) } - mir - } else { - // Get the revealed type of this const. This is *not* the adjusted - // type of its body, which may be a subtype of this type. For - // example: - // - // fn foo(_: &()) {} - // static X: fn(&'static ()) = foo; - // - // The adjusted type of the body of X is `for<'a> fn(&'a ())` which - // is not the same as the type of X. We need the type of the return - // place to be the type of the constant because NLL typeck will - // equate them. - - let return_ty = typeck_results.node_type(id); - - let (thir, expr) = tcx - .thir_body(def) - .unwrap_or_else(|_| (tcx.alloc_steal_thir(Thir::new()), ExprId::from_u32(0))); - // We ran all queries that depended on THIR at the beginning - // of `mir_build`, so now we can steal it - let thir = thir.steal(); - - build::construct_const(&thir, &infcx, expr, def, id, return_ty, return_ty_span) - }; + } + }; - lints::check(tcx, &body); - - // The borrow checker will replace all the regions here with its own - // inference variables. There's no point having non-erased regions here. - // The exception is `body.user_type_annotations`, which is used unmodified - // by borrow checking. - debug_assert!( - !(body.local_decls.has_free_regions() - || body.basic_blocks().has_free_regions() - || body.var_debug_info.has_free_regions() - || body.yield_ty().has_free_regions()), - "Unexpected free regions in MIR: {:?}", - body, - ); + lints::check(tcx, &body); + + // The borrow checker will replace all the regions here with its own + // inference variables. There's no point having non-erased regions here. + // The exception is `body.user_type_annotations`, which is used unmodified + // by borrow checking. + debug_assert!( + !(body.local_decls.has_free_regions() + || body.basic_blocks.has_free_regions() + || body.var_debug_info.has_free_regions() + || body.yield_ty().has_free_regions()), + "Unexpected free regions in MIR: {:?}", + body, + ); - body - }) + body } /////////////////////////////////////////////////////////////////////////// // BuildMir -- walks a crate, looking for fn items and methods to build MIR from -fn liberated_closure_env_ty( - tcx: TyCtxt<'_>, - closure_expr_id: hir::HirId, - body_id: hir::BodyId, -) -> Ty<'_> { - let closure_ty = tcx.typeck_body(body_id).node_type(closure_expr_id); - - let ty::Closure(closure_def_id, closure_substs) = *closure_ty.kind() else { - bug!("closure expr does not have closure type: {:?}", closure_ty); - }; - - let bound_vars = - tcx.mk_bound_variable_kinds(std::iter::once(ty::BoundVariableKind::Region(ty::BrEnv))); - let br = - ty::BoundRegion { var: ty::BoundVar::from_usize(bound_vars.len() - 1), kind: ty::BrEnv }; - let env_region = ty::ReLateBound(ty::INNERMOST, br); - let closure_env_ty = tcx.closure_env_ty(closure_def_id, closure_substs, env_region).unwrap(); - tcx.erase_late_bound_regions(ty::Binder::bind_with_vars(closure_env_ty, bound_vars)) -} - #[derive(Debug, PartialEq, Eq)] enum BlockFrame { /// Evaluation is currently within a statement. @@ -352,7 +157,7 @@ struct BlockContext(Vec); struct Builder<'a, 'tcx> { tcx: TyCtxt<'tcx>, - infcx: &'a InferCtxt<'a, 'tcx>, + infcx: InferCtxt<'a, 'tcx>, typeck_results: &'tcx TypeckResults<'tcx>, region_scope_tree: &'tcx region::ScopeTree, param_env: ty::ParamEnv<'tcx>, @@ -404,12 +209,21 @@ struct Builder<'a, 'tcx> { var_indices: FxHashMap, local_decls: IndexVec>, canonical_user_type_annotations: ty::CanonicalUserTypeAnnotations<'tcx>, - upvar_mutbls: Vec, + upvars: CaptureMap<'tcx>, unit_temp: Option>, var_debug_info: Vec>, } +type CaptureMap<'tcx> = SortedIndexMultiMap>; + +#[derive(Debug)] +struct Capture<'tcx> { + captured_place: &'tcx ty::CapturedPlace<'tcx>, + use_place: Place<'tcx>, + mutability: Mutability, +} + impl<'a, 'tcx> Builder<'a, 'tcx> { fn is_bound_var_in_guard(&self, id: LocalVarId) -> bool { self.guard_context.iter().any(|frame| frame.locals.iter().any(|local| local.id == id)) @@ -615,149 +429,212 @@ macro_rules! unpack { /////////////////////////////////////////////////////////////////////////// /// the main entry point for building MIR for a function -struct ArgInfo<'tcx>( - Ty<'tcx>, - Option, - Option<&'tcx hir::Param<'tcx>>, - Option, -); - -fn construct_fn<'tcx, A>( - thir: &Thir<'tcx>, - infcx: &InferCtxt<'_, 'tcx>, +fn construct_fn<'tcx>( + tcx: TyCtxt<'tcx>, fn_def: ty::WithOptConstParam, - fn_id: hir::HirId, - arguments: A, - safety: Safety, - abi: Abi, - return_ty: Ty<'tcx>, - return_ty_span: Span, - body: &'tcx hir::Body<'tcx>, + thir: &Thir<'tcx>, expr: ExprId, - span_with_body: Span, -) -> Body<'tcx> -where - A: Iterator>, -{ - let arguments: Vec<_> = arguments.collect(); - - let tcx = infcx.tcx; - let span = tcx.hir().span(fn_id); - - let mut builder = Builder::new( - thir, - infcx, - fn_def, - fn_id, - span_with_body, - arguments.len(), - safety, - return_ty, - return_ty_span, - body.generator_kind, - ); +) -> Body<'tcx> { + let span = tcx.def_span(fn_def.did); + let fn_id = tcx.hir().local_def_id_to_hir_id(fn_def.did); + let generator_kind = tcx.generator_kind(fn_def.did); - let call_site_scope = - region::Scope { id: body.value.hir_id.local_id, data: region::ScopeData::CallSite }; - let arg_scope = - region::Scope { id: body.value.hir_id.local_id, data: region::ScopeData::Arguments }; - let source_info = builder.source_info(span); - let call_site_s = (call_site_scope, source_info); - unpack!(builder.in_scope(call_site_s, LintLevel::Inherited, |builder| { - let arg_scope_s = (arg_scope, source_info); - // Attribute epilogue to function's closing brace - let fn_end = span_with_body.shrink_to_hi(); - let return_block = - unpack!(builder.in_breakable_scope(None, Place::return_place(), fn_end, |builder| { - Some(builder.in_scope(arg_scope_s, LintLevel::Inherited, |builder| { - builder.args_and_body( - START_BLOCK, - fn_def.did, - &arguments, - arg_scope, - &thir[expr], - ) - })) - })); - let source_info = builder.source_info(fn_end); - builder.cfg.terminate(return_block, source_info, TerminatorKind::Return); - builder.build_drop_trees(); - return_block.unit() - })); + // Figure out what primary body this item has. + let body_id = tcx.hir().body_owned_by(fn_def.did); + let span_with_body = tcx.hir().span_with_body(fn_id); + let return_ty_span = tcx + .hir() + .fn_decl_by_hir_id(fn_id) + .unwrap_or_else(|| span_bug!(span, "can't build MIR for {:?}", fn_def.did)) + .output + .span(); + + // fetch the fully liberated fn signature (that is, all bound + // types/lifetimes replaced) + let typeck_results = tcx.typeck_opt_const_arg(fn_def); + let fn_sig = typeck_results.liberated_fn_sigs()[fn_id]; + + let safety = match fn_sig.unsafety { + hir::Unsafety::Normal => Safety::Safe, + hir::Unsafety::Unsafe => Safety::FnUnsafe, + }; + + let mut abi = fn_sig.abi; + if let DefKind::Closure = tcx.def_kind(fn_def.did) { + // HACK(eddyb) Avoid having RustCall on closures, + // as it adds unnecessary (and wrong) auto-tupling. + abi = Abi::Rust; + } + + let arguments = &thir.params; + + let (yield_ty, return_ty) = if generator_kind.is_some() { + let gen_ty = arguments[thir::UPVAR_ENV_PARAM].ty; + let gen_sig = match gen_ty.kind() { + ty::Generator(_, gen_substs, ..) => gen_substs.as_generator().sig(), + _ => { + span_bug!(span, "generator w/o generator type: {:?}", gen_ty) + } + }; + (Some(gen_sig.yield_ty), gen_sig.return_ty) + } else { + (None, fn_sig.output()) + }; + + let mut body = tcx.infer_ctxt().enter(|infcx| { + let mut builder = Builder::new( + thir, + infcx, + fn_def, + fn_id, + span_with_body, + arguments.len(), + safety, + return_ty, + return_ty_span, + generator_kind, + ); + + let call_site_scope = + region::Scope { id: body_id.hir_id.local_id, data: region::ScopeData::CallSite }; + let arg_scope = + region::Scope { id: body_id.hir_id.local_id, data: region::ScopeData::Arguments }; + let source_info = builder.source_info(span); + let call_site_s = (call_site_scope, source_info); + unpack!(builder.in_scope(call_site_s, LintLevel::Inherited, |builder| { + let arg_scope_s = (arg_scope, source_info); + // Attribute epilogue to function's closing brace + let fn_end = span_with_body.shrink_to_hi(); + let return_block = unpack!(builder.in_breakable_scope( + None, + Place::return_place(), + fn_end, + |builder| { + Some(builder.in_scope(arg_scope_s, LintLevel::Inherited, |builder| { + builder.args_and_body( + START_BLOCK, + fn_def.did, + arguments, + arg_scope, + &thir[expr], + ) + })) + } + )); + let source_info = builder.source_info(fn_end); + builder.cfg.terminate(return_block, source_info, TerminatorKind::Return); + builder.build_drop_trees(); + return_block.unit() + })); + + builder.finish() + }); - let spread_arg = if abi == Abi::RustCall { + body.spread_arg = if abi == Abi::RustCall { // RustCall pseudo-ABI untuples the last argument. Some(Local::new(arguments.len())) } else { None }; - - let mut body = builder.finish(); - body.spread_arg = spread_arg; + if yield_ty.is_some() { + body.generator.as_mut().unwrap().yield_ty = yield_ty; + } body } fn construct_const<'a, 'tcx>( + tcx: TyCtxt<'tcx>, + def: ty::WithOptConstParam, thir: &'a Thir<'tcx>, - infcx: &'a InferCtxt<'a, 'tcx>, expr: ExprId, - def: ty::WithOptConstParam, - hir_id: hir::HirId, - const_ty: Ty<'tcx>, - const_ty_span: Span, ) -> Body<'tcx> { - let tcx = infcx.tcx; - let span = tcx.hir().span(hir_id); - let mut builder = Builder::new( - thir, - infcx, - def, - hir_id, - span, - 0, - Safety::Safe, - const_ty, - const_ty_span, - None, - ); + let hir_id = tcx.hir().local_def_id_to_hir_id(def.did); + + // Figure out what primary body this item has. + let (span, const_ty_span) = match tcx.hir().get(hir_id) { + Node::Item(hir::Item { + kind: hir::ItemKind::Static(ty, _, _) | hir::ItemKind::Const(ty, _), + span, + .. + }) + | Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Const(ty, _), span, .. }) + | Node::TraitItem(hir::TraitItem { + kind: hir::TraitItemKind::Const(ty, Some(_)), + span, + .. + }) => (*span, ty.span), + Node::AnonConst(_) => { + let span = tcx.def_span(def.did); + (span, span) + } + _ => span_bug!(tcx.def_span(def.did), "can't build MIR for {:?}", def.did), + }; + + // Get the revealed type of this const. This is *not* the adjusted + // type of its body, which may be a subtype of this type. For + // example: + // + // fn foo(_: &()) {} + // static X: fn(&'static ()) = foo; + // + // The adjusted type of the body of X is `for<'a> fn(&'a ())` which + // is not the same as the type of X. We need the type of the return + // place to be the type of the constant because NLL typeck will + // equate them. + let typeck_results = tcx.typeck_opt_const_arg(def); + let const_ty = typeck_results.node_type(hir_id); + + tcx.infer_ctxt().enter(|infcx| { + let mut builder = Builder::new( + thir, + infcx, + def, + hir_id, + span, + 0, + Safety::Safe, + const_ty, + const_ty_span, + None, + ); - let mut block = START_BLOCK; - unpack!(block = builder.expr_into_dest(Place::return_place(), block, &thir[expr])); + let mut block = START_BLOCK; + unpack!(block = builder.expr_into_dest(Place::return_place(), block, &thir[expr])); - let source_info = builder.source_info(span); - builder.cfg.terminate(block, source_info, TerminatorKind::Return); + let source_info = builder.source_info(span); + builder.cfg.terminate(block, source_info, TerminatorKind::Return); - builder.build_drop_trees(); + builder.build_drop_trees(); - builder.finish() + builder.finish() + }) } /// Construct MIR for an item that has had errors in type checking. /// /// This is required because we may still want to run MIR passes on an item /// with type errors, but normal MIR construction can't handle that in general. -fn construct_error<'a, 'tcx>( - infcx: &'a InferCtxt<'a, 'tcx>, - def: ty::WithOptConstParam, - hir_id: hir::HirId, - body_id: hir::BodyId, +fn construct_error<'tcx>( + tcx: TyCtxt<'tcx>, + def: LocalDefId, body_owner_kind: hir::BodyOwnerKind, err: ErrorGuaranteed, ) -> Body<'tcx> { - let tcx = infcx.tcx; - let span = tcx.hir().span(hir_id); + let span = tcx.def_span(def); + let hir_id = tcx.hir().local_def_id_to_hir_id(def); + let generator_kind = tcx.generator_kind(def); + let ty = tcx.ty_error(); - let generator_kind = tcx.hir().body(body_id).generator_kind; let num_params = match body_owner_kind { - hir::BodyOwnerKind::Fn => tcx.hir().fn_decl_by_hir_id(hir_id).unwrap().inputs.len(), + hir::BodyOwnerKind::Fn => tcx.fn_sig(def).inputs().skip_binder().len(), hir::BodyOwnerKind::Closure => { - if generator_kind.is_some() { - // Generators have an implicit `self` parameter *and* a possibly - // implicit resume parameter. - 2 - } else { - // The implicit self parameter adds another local in MIR. - 1 + tcx.hir().fn_decl_by_hir_id(hir_id).unwrap().inputs.len() + let ty = tcx.type_of(def); + match ty.kind() { + ty::Closure(_, substs) => { + 1 + substs.as_closure().sig().inputs().skip_binder().len() + } + ty::Generator(..) => 2, + _ => bug!("expected closure or generator, found {ty:?}"), } } hir::BodyOwnerKind::Const => 0, @@ -788,7 +665,7 @@ fn construct_error<'a, 'tcx>( cfg.terminate(START_BLOCK, source_info, TerminatorKind::Unreachable); let mut body = Body::new( - MirSource::item(def.did.to_def_id()), + MirSource::item(def.to_def_id()), cfg.basic_blocks, source_scopes, local_decls, @@ -806,7 +683,7 @@ fn construct_error<'a, 'tcx>( impl<'a, 'tcx> Builder<'a, 'tcx> { fn new( thir: &'a Thir<'tcx>, - infcx: &'a InferCtxt<'a, 'tcx>, + infcx: InferCtxt<'a, 'tcx>, def: ty::WithOptConstParam, hir_id: hir::HirId, span: Span, @@ -855,7 +732,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { in_scope_unsafe: safety, local_decls: IndexVec::from_elem_n(LocalDecl::new(return_ty, return_span), 1), canonical_user_type_annotations: IndexVec::new(), - upvar_mutbls: vec![], + upvars: CaptureMap::new(), var_indices: Default::default(), unit_temp: None, var_debug_info: vec![], @@ -896,20 +773,21 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { &mut self, mut block: BasicBlock, fn_def_id: LocalDefId, - arguments: &[ArgInfo<'tcx>], + arguments: &IndexVec>, argument_scope: region::Scope, expr: &Expr<'tcx>, ) -> BlockAnd<()> { // Allocate locals for the function arguments - for &ArgInfo(ty, _, arg_opt, _) in arguments.iter() { + for param in arguments.iter() { let source_info = - SourceInfo::outermost(arg_opt.map_or(self.fn_span, |arg| arg.pat.span)); - let arg_local = self.local_decls.push(LocalDecl::with_source_info(ty, source_info)); + SourceInfo::outermost(param.pat.as_ref().map_or(self.fn_span, |pat| pat.span)); + let arg_local = + self.local_decls.push(LocalDecl::with_source_info(param.ty, source_info)); // If this is a simple binding pattern, give debuginfo a nice name. - if let Some(arg) = arg_opt && let Some(ident) = arg.pat.simple_ident() { + if let Some(ref pat) = param.pat && let Some(name) = pat.simple_ident() { self.var_debug_info.push(VarDebugInfo { - name: ident.name, + name, source_info, value: VarDebugInfoContents::Place(arg_local.into()), }); @@ -924,7 +802,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // indexed closure and we stored in a map called closure_min_captures in TypeckResults // with the closure's DefId. Here, we run through that vec of UpvarIds for // the given closure and use the necessary information to create upvar - // debuginfo and to fill `self.upvar_mutbls`. + // debuginfo and to fill `self.upvars`. if hir_typeck_results.closure_min_captures.get(&fn_def_id).is_some() { let mut closure_env_projs = vec![]; let mut closure_ty = self.local_decls[ty::CAPTURE_STRUCT_LOCAL].ty; @@ -944,7 +822,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { .closure_min_captures_flattened(fn_def_id) .zip(capture_tys.zip(capture_syms)); - self.upvar_mutbls = captures_with_tys + self.upvars = captures_with_tys .enumerate() .map(|(i, (captured_place, (ty, sym)))| { let capture = captured_place.info.capture_kind; @@ -964,48 +842,46 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { } }; + let use_place = Place { + local: ty::CAPTURE_STRUCT_LOCAL, + projection: tcx.intern_place_elems(&projs), + }; self.var_debug_info.push(VarDebugInfo { name: *sym, source_info: SourceInfo::outermost(tcx_hir.span(var_id)), - value: VarDebugInfoContents::Place(Place { - local: ty::CAPTURE_STRUCT_LOCAL, - projection: tcx.intern_place_elems(&projs), - }), + value: VarDebugInfoContents::Place(use_place), }); - mutability + let capture = Capture { captured_place, use_place, mutability }; + (var_id, capture) }) .collect(); } let mut scope = None; // Bind the argument patterns - for (index, arg_info) in arguments.iter().enumerate() { + for (index, param) in arguments.iter().enumerate() { // Function arguments always get the first Local indices after the return place let local = Local::new(index + 1); let place = Place::from(local); - let &ArgInfo(_, opt_ty_info, arg_opt, ref self_binding) = arg_info; // Make sure we drop (parts of) the argument even when not matched on. self.schedule_drop( - arg_opt.as_ref().map_or(expr.span, |arg| arg.pat.span), + param.pat.as_ref().map_or(expr.span, |pat| pat.span), argument_scope, local, DropKind::Value, ); - let Some(arg) = arg_opt else { + let Some(ref pat) = param.pat else { continue; }; - let pat = match tcx.hir().get(arg.pat.hir_id) { - Node::Pat(pat) => pat, - node => bug!("pattern became {:?}", node), - }; - let pattern = pat_from_hir(tcx, self.param_env, self.typeck_results, pat); let original_source_scope = self.source_scope; - let span = pattern.span; - self.set_correct_source_scope_for_arg(arg.hir_id, original_source_scope, span); - match *pattern.kind { + let span = pat.span; + if let Some(arg_hir_id) = param.hir_id { + self.set_correct_source_scope_for_arg(arg_hir_id, original_source_scope, span); + } + match pat.kind { // Don't introduce extra copies for simple bindings PatKind::Binding { mutability, @@ -1016,17 +892,17 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { } => { self.local_decls[local].mutability = mutability; self.local_decls[local].source_info.scope = self.source_scope; - self.local_decls[local].local_info = if let Some(kind) = self_binding { + self.local_decls[local].local_info = if let Some(kind) = param.self_kind { Some(Box::new(LocalInfo::User(ClearCrossCrate::Set( - BindingForm::ImplicitSelf(*kind), + BindingForm::ImplicitSelf(kind), )))) } else { let binding_mode = ty::BindingMode::BindByValue(mutability); Some(Box::new(LocalInfo::User(ClearCrossCrate::Set(BindingForm::Var( VarBindingForm { binding_mode, - opt_ty_info, - opt_match_place: Some((Some(place), span)), + opt_ty_info: param.ty_span, + opt_match_place: Some((None, span)), pat_span: span, }, ))))) @@ -1037,12 +913,12 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { scope = self.declare_bindings( scope, expr.span, - &pattern, + &pat, matches::ArmHasGuard(false), Some((Some(&place), span)), ); let place_builder = PlaceBuilder::from(local); - unpack!(block = self.place_into_pattern(block, pattern, place_builder, false)); + unpack!(block = self.place_into_pattern(block, &pat, place_builder, false)); } } self.source_scope = original_source_scope; diff --git a/compiler/rustc_mir_build/src/build/scope.rs b/compiler/rustc_mir_build/src/build/scope.rs index b2fd9f25b..ff66ca595 100644 --- a/compiler/rustc_mir_build/src/build/scope.rs +++ b/compiler/rustc_mir_build/src/build/scope.rs @@ -466,9 +466,10 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let normal_exit_block = f(self); let breakable_scope = self.scopes.breakable_scopes.pop().unwrap(); assert!(breakable_scope.region_scope == region_scope); - let break_block = self.build_exit_tree(breakable_scope.break_drops, None); + let break_block = + self.build_exit_tree(breakable_scope.break_drops, region_scope, span, None); if let Some(drops) = breakable_scope.continue_drops { - self.build_exit_tree(drops, loop_block); + self.build_exit_tree(drops, region_scope, span, loop_block); } match (normal_exit_block, break_block) { (Some(block), None) | (None, Some(block)) => block, @@ -510,6 +511,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { pub(crate) fn in_if_then_scope( &mut self, region_scope: region::Scope, + span: Span, f: F, ) -> (BasicBlock, BasicBlock) where @@ -524,7 +526,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { assert!(if_then_scope.region_scope == region_scope); let else_block = self - .build_exit_tree(if_then_scope.else_drops, None) + .build_exit_tree(if_then_scope.else_drops, region_scope, span, None) .map_or_else(|| self.cfg.start_new_block(), |else_block_and| unpack!(else_block_and)); (then_block, else_block) @@ -997,10 +999,18 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { /// Returns the [DropIdx] for the innermost drop if the function unwound at /// this point. The `DropIdx` will be created if it doesn't already exist. fn diverge_cleanup(&mut self) -> DropIdx { - let is_generator = self.generator_kind.is_some(); - let (uncached_scope, mut cached_drop) = self - .scopes - .scopes + // It is okay to use dummy span because the getting scope index on the topmost scope + // must always succeed. + self.diverge_cleanup_target(self.scopes.topmost(), DUMMY_SP) + } + + /// This is similar to [diverge_cleanup](Self::diverge_cleanup) except its target is set to + /// some ancestor scope instead of the current scope. + /// It is possible to unwind to some ancestor scope if some drop panics as + /// the program breaks out of a if-then scope. + fn diverge_cleanup_target(&mut self, target_scope: region::Scope, span: Span) -> DropIdx { + let target = self.scopes.scope_index(target_scope, span); + let (uncached_scope, mut cached_drop) = self.scopes.scopes[..=target] .iter() .enumerate() .rev() @@ -1009,7 +1019,12 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { }) .unwrap_or((0, ROOT_NODE)); - for scope in &mut self.scopes.scopes[uncached_scope..] { + if uncached_scope > target { + return cached_drop; + } + + let is_generator = self.generator_kind.is_some(); + for scope in &mut self.scopes.scopes[uncached_scope..=target] { for drop in &scope.drops { if is_generator || drop.kind == DropKind::Value { cached_drop = self.scopes.unwind_drops.add_drop(*drop, cached_drop); @@ -1222,21 +1237,24 @@ impl<'a, 'tcx: 'a> Builder<'a, 'tcx> { fn build_exit_tree( &mut self, mut drops: DropTree, + else_scope: region::Scope, + span: Span, continue_block: Option, ) -> Option> { let mut blocks = IndexVec::from_elem(None, &drops.drops); blocks[ROOT_NODE] = continue_block; drops.build_mir::(&mut self.cfg, &mut blocks); + let is_generator = self.generator_kind.is_some(); // Link the exit drop tree to unwind drop tree. if drops.drops.iter().any(|(drop, _)| drop.kind == DropKind::Value) { - let unwind_target = self.diverge_cleanup(); + let unwind_target = self.diverge_cleanup_target(else_scope, span); let mut unwind_indices = IndexVec::from_elem_n(unwind_target, 1); for (drop_idx, drop_data) in drops.drops.iter_enumerated().skip(1) { match drop_data.0.kind { DropKind::Storage => { - if self.generator_kind.is_some() { + if is_generator { let unwind_drop = self .scopes .unwind_drops -- cgit v1.2.3