From da0fe80137e59708ca809f1a7e0e89e62e3ffcda Mon Sep 17 00:00:00 2001 From: b-naber Date: Tue, 7 Mar 2023 12:44:31 +0000 Subject: [PATCH] assertion for only collection nll region variable information for debug in non-canonicalization contexts --- compiler/rustc_borrowck/src/lib.rs | 18 +++-------- .../src/type_check/relate_tys.rs | 18 +++++------ compiler/rustc_infer/src/infer/at.rs | 3 ++ .../src/infer/canonical/canonicalizer.rs | 2 ++ compiler/rustc_infer/src/infer/mod.rs | 32 +++++++++++++++++++ 5 files changed, 49 insertions(+), 24 deletions(-) diff --git a/compiler/rustc_borrowck/src/lib.rs b/compiler/rustc_borrowck/src/lib.rs index 5e77f6b190a..80c7bfaf396 100644 --- a/compiler/rustc_borrowck/src/lib.rs +++ b/compiler/rustc_borrowck/src/lib.rs @@ -511,16 +511,11 @@ impl<'cx, 'tcx> BorrowckInferCtxt<'cx, 'tcx> { .as_var() .unwrap_or_else(|| bug!("expected RegionKind::RegionVar on {:?}", next_region)); - if cfg!(debug_assertions) { + if cfg!(debug_assertions) && !self.inside_canonicalization_ctxt() { debug!("inserting vid {:?} with origin {:?} into var_to_origin", vid, origin); let ctxt = get_ctxt_fn(); let mut var_to_origin = self.reg_var_to_origin.borrow_mut(); - let prev = var_to_origin.insert(vid, ctxt); - - // This only makes sense if not called in a canonicalization context. If this - // ever changes we either want to get rid of `BorrowckInferContext::reg_var_to_origin` - // or modify how we track nll region vars for that map. - assert!(matches!(prev, None)); + var_to_origin.insert(vid, ctxt); } next_region @@ -540,16 +535,11 @@ impl<'cx, 'tcx> BorrowckInferCtxt<'cx, 'tcx> { .as_var() .unwrap_or_else(|| bug!("expected RegionKind::RegionVar on {:?}", next_region)); - if cfg!(debug_assertions) { + if cfg!(debug_assertions) && !self.inside_canonicalization_ctxt() { debug!("inserting vid {:?} with origin {:?} into var_to_origin", vid, origin); let ctxt = get_ctxt_fn(); let mut var_to_origin = self.reg_var_to_origin.borrow_mut(); - let prev = var_to_origin.insert(vid, ctxt); - - // This only makes sense if not called in a canonicalization context. If this - // ever changes we either want to get rid of `BorrowckInferContext::reg_var_to_origin` - // or modify how we track nll region vars for that map. - assert!(matches!(prev, None)); + var_to_origin.insert(vid, ctxt); } next_region diff --git a/compiler/rustc_borrowck/src/type_check/relate_tys.rs b/compiler/rustc_borrowck/src/type_check/relate_tys.rs index d96372fb99b..305e2c8fe8e 100644 --- a/compiler/rustc_borrowck/src/type_check/relate_tys.rs +++ b/compiler/rustc_borrowck/src/type_check/relate_tys.rs @@ -132,9 +132,12 @@ impl<'tcx> TypeRelatingDelegate<'tcx> for NllTypeRelatingDelegate<'_, '_, 'tcx> let reg_var = reg.as_var().unwrap_or_else(|| bug!("expected region {:?} to be of kind ReVar", reg)); - let mut var_to_origin = self.type_checker.infcx.reg_var_to_origin.borrow_mut(); - let prev = var_to_origin.insert(reg_var, RegionCtxt::Placeholder(reg_info)); - assert!(matches!(prev, None)); + + if cfg!(debug_assertions) && !self.type_checker.infcx.inside_canonicalization_ctxt() { + let mut var_to_origin = self.type_checker.infcx.reg_var_to_origin.borrow_mut(); + debug!(?reg_var); + var_to_origin.insert(reg_var, RegionCtxt::Placeholder(reg_info)); + } reg } @@ -149,14 +152,9 @@ impl<'tcx> TypeRelatingDelegate<'tcx> for NllTypeRelatingDelegate<'_, '_, 'tcx> let reg_var = reg.as_var().unwrap_or_else(|| bug!("expected region {:?} to be of kind ReVar", reg)); - if cfg!(debug_assertions) { + if cfg!(debug_assertions) && !self.type_checker.infcx.inside_canonicalization_ctxt() { let mut var_to_origin = self.type_checker.infcx.reg_var_to_origin.borrow_mut(); - let prev = var_to_origin.insert(reg_var, RegionCtxt::Existential(None)); - - // It only makes sense to track region vars in non-canonicalization contexts. If this - // ever changes we either want to get rid of `BorrowckInferContext::reg_var_to_origin` - // or modify how we track nll region vars for that map. - assert!(matches!(prev, None)); + var_to_origin.insert(reg_var, RegionCtxt::Existential(None)); } reg diff --git a/compiler/rustc_infer/src/infer/at.rs b/compiler/rustc_infer/src/infer/at.rs index 0c8854e962a..d240d8e491f 100644 --- a/compiler/rustc_infer/src/infer/at.rs +++ b/compiler/rustc_infer/src/infer/at.rs @@ -30,6 +30,8 @@ use super::*; use rustc_middle::ty::relate::{Relate, TypeRelation}; use rustc_middle::ty::{Const, ImplSubject}; +use std::cell::Cell; + /// Whether we should define opaque types or just treat them opaquely. /// /// Currently only used to prevent predicate matching from matching anything @@ -82,6 +84,7 @@ impl<'tcx> InferCtxt<'tcx> { in_snapshot: self.in_snapshot.clone(), universe: self.universe.clone(), intercrate: self.intercrate, + inside_canonicalization_ctxt: Cell::new(self.inside_canonicalization_ctxt()), } } } diff --git a/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs b/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs index 8ac82653c0e..96a5f6532fe 100644 --- a/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs +++ b/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs @@ -561,6 +561,8 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> { where V: TypeFoldable>, { + let _inside_canonical_ctxt_guard = infcx.set_canonicalization_ctxt(); + let needs_canonical_flags = if canonicalize_region_mode.any() { TypeFlags::NEEDS_INFER | TypeFlags::HAS_FREE_REGIONS | // `HAS_RE_PLACEHOLDER` implies `HAS_FREE_REGIONS` diff --git a/compiler/rustc_infer/src/infer/mod.rs b/compiler/rustc_infer/src/infer/mod.rs index aeb4ddb4212..8f1a1579290 100644 --- a/compiler/rustc_infer/src/infer/mod.rs +++ b/compiler/rustc_infer/src/infer/mod.rs @@ -39,6 +39,7 @@ use rustc_span::Span; use std::cell::{Cell, RefCell}; use std::fmt; +use std::ops::Drop; use self::combine::CombineFields; use self::error_reporting::TypeErrCtxt; @@ -342,6 +343,11 @@ pub struct InferCtxt<'tcx> { /// there is no type that the user could *actually name* that /// would satisfy it. This avoids crippling inference, basically. pub intercrate: bool, + + /// Flag that is set when we enter canonicalization. Used for debugging to ensure + /// that we only collect region information for `BorrowckInferCtxt::reg_var_to_origin` + /// inside non-canonicalization contexts. + inside_canonicalization_ctxt: Cell, } /// See the `error_reporting` module for more details. @@ -633,6 +639,7 @@ impl<'tcx> InferCtxtBuilder<'tcx> { skip_leak_check: Cell::new(false), universe: Cell::new(ty::UniverseIndex::ROOT), intercrate, + inside_canonicalization_ctxt: Cell::new(false), } } } @@ -1728,6 +1735,31 @@ impl<'tcx> InferCtxt<'tcx> { } } } + + pub fn inside_canonicalization_ctxt(&self) -> bool { + self.inside_canonicalization_ctxt.get() + } + + pub fn set_canonicalization_ctxt(&self) -> CanonicalizationCtxtGuard<'_, 'tcx> { + let prev_ctxt = self.inside_canonicalization_ctxt(); + self.inside_canonicalization_ctxt.set(true); + CanonicalizationCtxtGuard { prev_ctxt, infcx: self } + } + + fn set_canonicalization_ctxt_to(&self, ctxt: bool) { + self.inside_canonicalization_ctxt.set(ctxt); + } +} + +pub struct CanonicalizationCtxtGuard<'cx, 'tcx> { + prev_ctxt: bool, + infcx: &'cx InferCtxt<'tcx>, +} + +impl<'cx, 'tcx> Drop for CanonicalizationCtxtGuard<'cx, 'tcx> { + fn drop(&mut self) { + self.infcx.set_canonicalization_ctxt_to(self.prev_ctxt) + } } impl<'tcx> TypeErrCtxt<'_, 'tcx> {