diff options
Diffstat (limited to 'compiler/rustc_mir_build/src/thir/pattern/mod.rs')
| -rw-r--r-- | compiler/rustc_mir_build/src/thir/pattern/mod.rs | 127 |
1 files changed, 73 insertions, 54 deletions
diff --git a/compiler/rustc_mir_build/src/thir/pattern/mod.rs b/compiler/rustc_mir_build/src/thir/pattern/mod.rs index a13748a2d..0edf6a983 100644 --- a/compiler/rustc_mir_build/src/thir/pattern/mod.rs +++ b/compiler/rustc_mir_build/src/thir/pattern/mod.rs @@ -29,27 +29,27 @@ use rustc_span::{Span, Symbol}; use std::cmp::Ordering; #[derive(Clone, Debug)] -pub(crate) enum PatternError { +enum PatternError { AssocConstInPattern(Span), ConstParamInPattern(Span), StaticInPattern(Span), NonConstPath(Span), } -pub(crate) struct PatCtxt<'a, 'tcx> { - pub(crate) tcx: TyCtxt<'tcx>, - pub(crate) param_env: ty::ParamEnv<'tcx>, - pub(crate) typeck_results: &'a ty::TypeckResults<'tcx>, - pub(crate) errors: Vec<PatternError>, +struct PatCtxt<'a, 'tcx> { + tcx: TyCtxt<'tcx>, + param_env: ty::ParamEnv<'tcx>, + typeck_results: &'a ty::TypeckResults<'tcx>, + errors: Vec<PatternError>, include_lint_checks: bool, } -pub(crate) fn pat_from_hir<'a, 'tcx>( +pub(super) fn pat_from_hir<'a, 'tcx>( tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>, typeck_results: &'a ty::TypeckResults<'tcx>, pat: &'tcx hir::Pat<'tcx>, -) -> Pat<'tcx> { +) -> Box<Pat<'tcx>> { let mut pcx = PatCtxt::new(tcx, param_env, typeck_results); let result = pcx.lower_pattern(pat); if !pcx.errors.is_empty() { @@ -61,7 +61,7 @@ pub(crate) fn pat_from_hir<'a, 'tcx>( } impl<'a, 'tcx> PatCtxt<'a, 'tcx> { - pub(crate) fn new( + fn new( tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>, typeck_results: &'a ty::TypeckResults<'tcx>, @@ -69,12 +69,12 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { PatCtxt { tcx, param_env, typeck_results, errors: vec![], include_lint_checks: false } } - pub(crate) fn include_lint_checks(&mut self) -> &mut Self { + fn include_lint_checks(&mut self) -> &mut Self { self.include_lint_checks = true; self } - pub(crate) fn lower_pattern(&mut self, pat: &'tcx hir::Pat<'tcx>) -> Pat<'tcx> { + fn lower_pattern(&mut self, pat: &'tcx hir::Pat<'tcx>) -> Box<Pat<'tcx>> { // When implicit dereferences have been inserted in this pattern, the unadjusted lowered // pattern has the type that results *after* dereferencing. For example, in this code: // @@ -97,13 +97,13 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { let unadjusted_pat = self.lower_pattern_unadjusted(pat); self.typeck_results.pat_adjustments().get(pat.hir_id).unwrap_or(&vec![]).iter().rev().fold( unadjusted_pat, - |pat, ref_ty| { + |pat: Box<_>, ref_ty| { debug!("{:?}: wrapping pattern with type {:?}", pat, ref_ty); - Pat { + Box::new(Pat { span: pat.span, ty: *ref_ty, - kind: Box::new(PatKind::Deref { subpattern: pat }), - } + kind: PatKind::Deref { subpattern: pat }, + }) }, ) } @@ -113,7 +113,7 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { expr: &'tcx hir::Expr<'tcx>, ) -> (PatKind<'tcx>, Option<Ascription<'tcx>>) { match self.lower_lit(expr) { - PatKind::AscribeUserType { ascription, subpattern: Pat { kind: box kind, .. } } => { + PatKind::AscribeUserType { ascription, subpattern: box Pat { kind, .. } } => { (kind, Some(ascription)) } kind => (kind, None), @@ -134,7 +134,9 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { match (end, cmp) { // `x..y` where `x < y`. // Non-empty because the range includes at least `x`. - (RangeEnd::Excluded, Some(Ordering::Less)) => PatKind::Range(PatRange { lo, hi, end }), + (RangeEnd::Excluded, Some(Ordering::Less)) => { + PatKind::Range(Box::new(PatRange { lo, hi, end })) + } // `x..y` where `x >= y`. The range is empty => error. (RangeEnd::Excluded, _) => { struct_span_err!( @@ -149,7 +151,9 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { // `x..=y` where `x == y`. (RangeEnd::Included, Some(Ordering::Equal)) => PatKind::Constant { value: lo }, // `x..=y` where `x < y`. - (RangeEnd::Included, Some(Ordering::Less)) => PatKind::Range(PatRange { lo, hi, end }), + (RangeEnd::Included, Some(Ordering::Less)) => { + PatKind::Range(Box::new(PatRange { lo, hi, end })) + } // `x..=y` where `x > y` hence the range is empty => error. (RangeEnd::Included, _) => { let mut err = struct_span_err!( @@ -196,8 +200,9 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { } } - fn lower_pattern_unadjusted(&mut self, pat: &'tcx hir::Pat<'tcx>) -> Pat<'tcx> { + fn lower_pattern_unadjusted(&mut self, pat: &'tcx hir::Pat<'tcx>) -> Box<Pat<'tcx>> { let mut ty = self.typeck_results.node_type(pat.hir_id); + let mut span = pat.span; let kind = match pat.kind { hir::PatKind::Wild => PatKind::Wild, @@ -228,7 +233,7 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { // constants somewhere. Have them on the range pattern. for end in &[lo, hi] { if let Some((_, Some(ascription))) = end { - let subpattern = Pat { span: pat.span, ty, kind: Box::new(kind) }; + let subpattern = Box::new(Pat { span: pat.span, ty, kind }); kind = PatKind::AscribeUserType { ascription: ascription.clone(), subpattern }; } @@ -258,6 +263,10 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { } hir::PatKind::Binding(_, id, ident, ref sub) => { + if let Some(ident_span) = ident.span.find_ancestor_inside(span) { + span = span.with_hi(ident_span.hi()); + } + let bm = *self .typeck_results .pat_binding_modes() @@ -322,14 +331,14 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { hir::PatKind::Or(ref pats) => PatKind::Or { pats: self.lower_patterns(pats) }, }; - Pat { span: pat.span, ty, kind: Box::new(kind) } + Box::new(Pat { span, ty, kind }) } fn lower_tuple_subpats( &mut self, pats: &'tcx [hir::Pat<'tcx>], expected_len: usize, - gap_pos: Option<usize>, + gap_pos: hir::DotDotPos, ) -> Vec<FieldPat<'tcx>> { pats.iter() .enumerate_and_adjust(expected_len, gap_pos) @@ -340,11 +349,14 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { .collect() } - fn lower_patterns(&mut self, pats: &'tcx [hir::Pat<'tcx>]) -> Vec<Pat<'tcx>> { + fn lower_patterns(&mut self, pats: &'tcx [hir::Pat<'tcx>]) -> Box<[Box<Pat<'tcx>>]> { pats.iter().map(|p| self.lower_pattern(p)).collect() } - fn lower_opt_pattern(&mut self, pat: &'tcx Option<&'tcx hir::Pat<'tcx>>) -> Option<Pat<'tcx>> { + fn lower_opt_pattern( + &mut self, + pat: &'tcx Option<&'tcx hir::Pat<'tcx>>, + ) -> Option<Box<Pat<'tcx>>> { pat.as_ref().map(|p| self.lower_pattern(p)) } @@ -436,12 +448,12 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { if let Some(user_ty) = self.user_substs_applied_to_ty_of_hir_id(hir_id) { debug!("lower_variant_or_leaf: kind={:?} user_ty={:?} span={:?}", kind, user_ty, span); let annotation = CanonicalUserTypeAnnotation { - user_ty, + user_ty: Box::new(user_ty), span, inferred_ty: self.typeck_results.node_type(hir_id), }; kind = PatKind::AscribeUserType { - subpattern: Pat { span, ty, kind: Box::new(kind) }, + subpattern: Box::new(Pat { span, ty, kind }), ascription: Ascription { annotation, variance: ty::Variance::Covariant }, }; } @@ -453,11 +465,11 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { /// it to `const_to_pat`. Any other path (like enum variants without fields) /// is converted to the corresponding pattern via `lower_variant_or_leaf`. #[instrument(skip(self), level = "debug")] - fn lower_path(&mut self, qpath: &hir::QPath<'_>, id: hir::HirId, span: Span) -> Pat<'tcx> { + fn lower_path(&mut self, qpath: &hir::QPath<'_>, id: hir::HirId, span: Span) -> Box<Pat<'tcx>> { let ty = self.typeck_results.node_type(id); let res = self.typeck_results.qpath_res(qpath, id); - let pat_from_kind = |kind| Pat { span, ty, kind: Box::new(kind) }; + let pat_from_kind = |kind| Box::new(Pat { span, ty, kind }); let (def_id, is_associated_const) = match res { Res::Def(DefKind::Const, def_id) => (def_id, false), @@ -469,7 +481,12 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { // Use `Reveal::All` here because patterns are always monomorphic even if their function // isn't. let param_env_reveal_all = self.param_env.with_reveal_all_normalized(self.tcx); - let substs = self.typeck_results.node_substs(id); + // N.B. There is no guarantee that substs collected in typeck results are fully normalized, + // so they need to be normalized in order to pass to `Instance::resolve`, which will ICE + // if given unnormalized types. + let substs = self + .tcx + .normalize_erasing_regions(param_env_reveal_all, self.typeck_results.node_substs(id)); let instance = match ty::Instance::resolve(self.tcx, param_env_reveal_all, def_id, substs) { Ok(Some(i)) => i, Ok(None) => { @@ -505,13 +522,13 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { let user_provided_types = self.typeck_results().user_provided_types(); if let Some(&user_ty) = user_provided_types.get(id) { let annotation = CanonicalUserTypeAnnotation { - user_ty, + user_ty: Box::new(user_ty), span, inferred_ty: self.typeck_results().node_type(id), }; - Pat { + Box::new(Pat { span, - kind: Box::new(PatKind::AscribeUserType { + kind: PatKind::AscribeUserType { subpattern: pattern, ascription: Ascription { annotation, @@ -519,9 +536,9 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { /// `variance` field documentation for details. variance: ty::Variance::Contravariant, }, - }), + }, ty: const_.ty(), - } + }) } else { pattern } @@ -553,23 +570,19 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { let value = value.eval(self.tcx, self.param_env); match value { - mir::ConstantKind::Ty(c) => { - match c.kind() { - ConstKind::Param(_) => { - self.errors.push(PatternError::ConstParamInPattern(span)); - return PatKind::Wild; - } - ConstKind::Unevaluated(_) => { - // If we land here it means the const can't be evaluated because it's `TooGeneric`. - self.tcx - .sess - .span_err(span, "constant pattern depends on a generic parameter"); - return PatKind::Wild; - } - _ => bug!("Expected either ConstKind::Param or ConstKind::Unevaluated"), + mir::ConstantKind::Ty(c) => match c.kind() { + ConstKind::Param(_) => { + self.errors.push(PatternError::ConstParamInPattern(span)); + return PatKind::Wild; } + _ => bug!("Expected ConstKind::Param"), + }, + mir::ConstantKind::Val(_, _) => self.const_to_pat(value, id, span, false).kind, + mir::ConstantKind::Unevaluated(..) => { + // If we land here it means the const can't be evaluated because it's `TooGeneric`. + self.tcx.sess.span_err(span, "constant pattern depends on a generic parameter"); + return PatKind::Wild; } - mir::ConstantKind::Val(_, _) => *self.const_to_pat(value, id, span, false).kind, } } @@ -580,7 +593,7 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { fn lower_lit(&mut self, expr: &'tcx hir::Expr<'tcx>) -> PatKind<'tcx> { let (lit, neg) = match expr.kind { hir::ExprKind::Path(ref qpath) => { - return *self.lower_path(qpath, expr.hir_id, expr.span).kind; + return self.lower_path(qpath, expr.hir_id, expr.span).kind; } hir::ExprKind::ConstBlock(ref anon_const) => { return self.lower_inline_const(anon_const, expr.hir_id, expr.span); @@ -598,7 +611,7 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { let lit_input = LitToConstInput { lit: &lit.node, ty: self.typeck_results.expr_ty(expr), neg }; match self.tcx.at(expr.span).lit_to_mir_constant(lit_input) { - Ok(constant) => *self.const_to_pat(constant, expr.hir_id, lit.span, false).kind, + Ok(constant) => self.const_to_pat(constant, expr.hir_id, lit.span, false).kind, Err(LitToConstError::Reported) => PatKind::Wild, Err(LitToConstError::TypeError) => bug!("lower_lit: had type error"), } @@ -615,7 +628,7 @@ impl<'tcx> UserAnnotatedTyHelpers<'tcx> for PatCtxt<'_, 'tcx> { } } -pub(crate) trait PatternFoldable<'tcx>: Sized { +trait PatternFoldable<'tcx>: Sized { fn fold_with<F: PatternFolder<'tcx>>(&self, folder: &mut F) -> Self { self.super_fold_with(folder) } @@ -623,7 +636,7 @@ pub(crate) trait PatternFoldable<'tcx>: Sized { fn super_fold_with<F: PatternFolder<'tcx>>(&self, folder: &mut F) -> Self; } -pub(crate) trait PatternFolder<'tcx>: Sized { +trait PatternFolder<'tcx>: Sized { fn fold_pattern(&mut self, pattern: &Pat<'tcx>) -> Pat<'tcx> { pattern.super_fold_with(self) } @@ -646,6 +659,12 @@ impl<'tcx, T: PatternFoldable<'tcx>> PatternFoldable<'tcx> for Vec<T> { } } +impl<'tcx, T: PatternFoldable<'tcx>> PatternFoldable<'tcx> for Box<[T]> { + fn super_fold_with<F: PatternFolder<'tcx>>(&self, folder: &mut F) -> Self { + self.iter().map(|t| t.fold_with(folder)).collect() + } +} + impl<'tcx, T: PatternFoldable<'tcx>> PatternFoldable<'tcx> for Option<T> { fn super_fold_with<F: PatternFolder<'tcx>>(&self, folder: &mut F) -> Self { self.as_ref().map(|t| t.fold_with(folder)) @@ -732,7 +751,7 @@ impl<'tcx> PatternFoldable<'tcx> for PatKind<'tcx> { PatKind::Deref { subpattern: subpattern.fold_with(folder) } } PatKind::Constant { value } => PatKind::Constant { value }, - PatKind::Range(range) => PatKind::Range(range), + PatKind::Range(ref range) => PatKind::Range(range.clone()), PatKind::Slice { ref prefix, ref slice, ref suffix } => PatKind::Slice { prefix: prefix.fold_with(folder), slice: slice.fold_with(folder), |