diff --git a/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs b/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs index e4b37f05b778f..30ca70326fa87 100644 --- a/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs +++ b/compiler/rustc_infer/src/infer/canonical/canonicalizer.rs @@ -480,7 +480,7 @@ impl<'cx, 'tcx> TypeFolder> for Canonicalizer<'cx, 'tcx> { } ty::ConstKind::Infer(InferConst::EffectVar(vid)) => { match self.infcx.unwrap().probe_effect_var(vid) { - Some(value) => return self.fold_const(value.as_const(self.tcx)), + Some(value) => return self.fold_const(value), None => { return self.canonicalize_const_var( CanonicalVarInfo { kind: CanonicalVarKind::Effect }, diff --git a/compiler/rustc_infer/src/infer/canonical/mod.rs b/compiler/rustc_infer/src/infer/canonical/mod.rs index 386fdb09ba5d5..1f68a5a9c6179 100644 --- a/compiler/rustc_infer/src/infer/canonical/mod.rs +++ b/compiler/rustc_infer/src/infer/canonical/mod.rs @@ -24,6 +24,7 @@ use crate::infer::{ConstVariableOrigin, ConstVariableOriginKind}; use crate::infer::{InferCtxt, RegionVariableOrigin, TypeVariableOrigin, TypeVariableOriginKind}; use rustc_index::IndexVec; +use rustc_middle::infer::unify_key::EffectVarValue; use rustc_middle::ty::fold::TypeFoldable; use rustc_middle::ty::GenericArg; use rustc_middle::ty::{self, List, Ty, TyCtxt}; @@ -152,7 +153,12 @@ impl<'tcx> InferCtxt<'tcx> { ) .into(), CanonicalVarKind::Effect => { - let vid = self.inner.borrow_mut().effect_unification_table().new_key(None).vid; + let vid = self + .inner + .borrow_mut() + .effect_unification_table() + .new_key(EffectVarValue::Unknown) + .vid; ty::Const::new_infer(self.tcx, ty::InferConst::EffectVar(vid), self.tcx.types.bool) .into() } diff --git a/compiler/rustc_infer/src/infer/freshen.rs b/compiler/rustc_infer/src/infer/freshen.rs index d256994d8d1fd..2d5fa1b5c7001 100644 --- a/compiler/rustc_infer/src/infer/freshen.rs +++ b/compiler/rustc_infer/src/infer/freshen.rs @@ -151,13 +151,8 @@ impl<'a, 'tcx> TypeFolder> for TypeFreshener<'a, 'tcx> { self.freshen_const(opt_ct, ty::InferConst::Var(v), ty::InferConst::Fresh, ct.ty()) } ty::ConstKind::Infer(ty::InferConst::EffectVar(v)) => { - let opt_ct = self - .infcx - .inner - .borrow_mut() - .effect_unification_table() - .probe_value(v) - .map(|effect| effect.as_const(self.infcx.tcx)); + let opt_ct = + self.infcx.inner.borrow_mut().effect_unification_table().probe_value(v).known(); self.freshen_const( opt_ct, ty::InferConst::EffectVar(v), diff --git a/compiler/rustc_infer/src/infer/mod.rs b/compiler/rustc_infer/src/infer/mod.rs index 0a39fe007fd22..13baecf6002c0 100644 --- a/compiler/rustc_infer/src/infer/mod.rs +++ b/compiler/rustc_infer/src/infer/mod.rs @@ -8,6 +8,7 @@ pub use self::ValuePairs::*; pub use relate::combine::ObligationEmittingRelation; use rustc_data_structures::captures::Captures; use rustc_data_structures::undo_log::UndoLogs; +use rustc_middle::infer::unify_key::EffectVarValue; use rustc_middle::infer::unify_key::{ConstVidKey, EffectVidKey}; use self::opaque_types::OpaqueTypeStorage; @@ -25,8 +26,8 @@ use rustc_data_structures::unify as ut; use rustc_errors::{DiagCtxt, DiagnosticBuilder, ErrorGuaranteed}; use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_middle::infer::canonical::{Canonical, CanonicalVarValues}; +use rustc_middle::infer::unify_key::ConstVariableValue; use rustc_middle::infer::unify_key::{ConstVariableOrigin, ConstVariableOriginKind, ToType}; -use rustc_middle::infer::unify_key::{ConstVariableValue, EffectVarValue}; use rustc_middle::mir::interpret::{ErrorHandled, EvalToValTreeResult}; use rustc_middle::mir::ConstraintCategory; use rustc_middle::traits::{select, DefiningAnchor}; @@ -818,7 +819,7 @@ impl<'tcx> InferCtxt<'tcx> { (0..table.len()) .map(|i| ty::EffectVid::from_usize(i)) - .filter(|&vid| table.probe_value(vid).is_none()) + .filter(|&vid| table.probe_value(vid).is_unknown()) .map(|v| { ty::Const::new_infer(self.tcx, ty::InferConst::EffectVar(v), self.tcx.types.bool) }) @@ -1236,7 +1237,8 @@ impl<'tcx> InferCtxt<'tcx> { } pub fn var_for_effect(&self, param: &ty::GenericParamDef) -> GenericArg<'tcx> { - let effect_vid = self.inner.borrow_mut().effect_unification_table().new_key(None).vid; + let effect_vid = + self.inner.borrow_mut().effect_unification_table().new_key(EffectVarValue::Unknown).vid; let ty = self .tcx .type_of(param.def_id) @@ -1416,8 +1418,8 @@ impl<'tcx> InferCtxt<'tcx> { } } - pub fn probe_effect_var(&self, vid: EffectVid) -> Option> { - self.inner.borrow_mut().effect_unification_table().probe_value(vid) + pub fn probe_effect_var(&self, vid: EffectVid) -> Option> { + self.inner.borrow_mut().effect_unification_table().probe_value(vid).known() } /// Attempts to resolve all type/region/const variables in @@ -1893,7 +1895,8 @@ impl<'a, 'tcx> TypeFolder> for ShallowResolver<'a, 'tcx> { .borrow_mut() .effect_unification_table() .probe_value(vid) - .map_or(ct, |val| val.as_const(self.infcx.tcx)), + .known() + .unwrap_or(ct), _ => ct, } } diff --git a/compiler/rustc_infer/src/infer/relate/combine.rs b/compiler/rustc_infer/src/infer/relate/combine.rs index 1c120646f1f90..13c17ee1cd2b8 100644 --- a/compiler/rustc_infer/src/infer/relate/combine.rs +++ b/compiler/rustc_infer/src/infer/relate/combine.rs @@ -202,11 +202,7 @@ impl<'tcx> InferCtxt<'tcx> { ty::ConstKind::Infer(InferConst::EffectVar(a_vid)), ty::ConstKind::Infer(InferConst::EffectVar(b_vid)), ) => { - self.inner - .borrow_mut() - .effect_unification_table() - .unify_var_var(a_vid, b_vid) - .map_err(|a| effect_unification_error(self.tcx, relation.a_is_expected(), a))?; + self.inner.borrow_mut().effect_unification_table().union(a_vid, b_vid); return Ok(a); } @@ -233,19 +229,11 @@ impl<'tcx> InferCtxt<'tcx> { } (ty::ConstKind::Infer(InferConst::EffectVar(vid)), _) => { - return self.unify_effect_variable( - relation.a_is_expected(), - vid, - EffectVarValue::Const(b), - ); + return Ok(self.unify_effect_variable(vid, b)); } (_, ty::ConstKind::Infer(InferConst::EffectVar(vid))) => { - return self.unify_effect_variable( - !relation.a_is_expected(), - vid, - EffectVarValue::Const(a), - ); + return Ok(self.unify_effect_variable(vid, a)); } (ty::ConstKind::Unevaluated(..), _) | (_, ty::ConstKind::Unevaluated(..)) @@ -366,18 +354,12 @@ impl<'tcx> InferCtxt<'tcx> { Ok(Ty::new_float(self.tcx, val)) } - fn unify_effect_variable( - &self, - vid_is_expected: bool, - vid: ty::EffectVid, - val: EffectVarValue<'tcx>, - ) -> RelateResult<'tcx, ty::Const<'tcx>> { + fn unify_effect_variable(&self, vid: ty::EffectVid, val: ty::Const<'tcx>) -> ty::Const<'tcx> { self.inner .borrow_mut() .effect_unification_table() - .unify_var_value(vid, Some(val)) - .map_err(|e| effect_unification_error(self.tcx, vid_is_expected, e))?; - Ok(val.as_const(self.tcx)) + .union_value(vid, EffectVarValue::Known(val)); + val } } @@ -579,11 +561,3 @@ fn float_unification_error<'tcx>( let (ty::FloatVarValue(a), ty::FloatVarValue(b)) = v; TypeError::FloatMismatch(ExpectedFound::new(a_is_expected, a, b)) } - -fn effect_unification_error<'tcx>( - _tcx: TyCtxt<'tcx>, - _a_is_expected: bool, - (_a, _b): (EffectVarValue<'tcx>, EffectVarValue<'tcx>), -) -> TypeError<'tcx> { - bug!("unexpected effect unification error") -} diff --git a/compiler/rustc_infer/src/infer/resolve.rs b/compiler/rustc_infer/src/infer/resolve.rs index 959b09031277c..d5999331dfab6 100644 --- a/compiler/rustc_infer/src/infer/resolve.rs +++ b/compiler/rustc_infer/src/infer/resolve.rs @@ -237,14 +237,13 @@ impl<'tcx> TypeFolder> for EagerResolver<'_, 'tcx> { } ty::ConstKind::Infer(ty::InferConst::EffectVar(vid)) => { debug_assert_eq!(c.ty(), self.infcx.tcx.types.bool); - match self.infcx.probe_effect_var(vid) { - Some(c) => c.as_const(self.infcx.tcx), - None => ty::Const::new_infer( + self.infcx.probe_effect_var(vid).unwrap_or_else(|| { + ty::Const::new_infer( self.infcx.tcx, ty::InferConst::EffectVar(self.infcx.root_effect_var(vid)), self.infcx.tcx.types.bool, - ), - } + ) + }) } _ => { if c.has_infer() { diff --git a/compiler/rustc_middle/src/infer/unify_key.rs b/compiler/rustc_middle/src/infer/unify_key.rs index c35799ef47f2b..63c0ebd5f6b79 100644 --- a/compiler/rustc_middle/src/infer/unify_key.rs +++ b/compiler/rustc_middle/src/infer/unify_key.rs @@ -194,33 +194,37 @@ impl<'tcx> UnifyValue for ConstVariableValue<'tcx> { /// values for the effect inference variable #[derive(Clone, Copy, Debug)] pub enum EffectVarValue<'tcx> { - /// The host effect is on, enabling access to syscalls, filesystem access, etc. - Host, - /// The host effect is off. Execution is restricted to const operations only. - NoHost, - Const(ty::Const<'tcx>), + Unknown, + Known(ty::Const<'tcx>), } impl<'tcx> EffectVarValue<'tcx> { - pub fn as_const(self, tcx: TyCtxt<'tcx>) -> ty::Const<'tcx> { + pub fn known(self) -> Option> { match self { - EffectVarValue::Host => tcx.consts.true_, - EffectVarValue::NoHost => tcx.consts.false_, - EffectVarValue::Const(c) => c, + EffectVarValue::Unknown => None, + EffectVarValue::Known(value) => Some(value), + } + } + + pub fn is_unknown(self) -> bool { + match self { + EffectVarValue::Unknown => true, + EffectVarValue::Known(_) => false, } } } impl<'tcx> UnifyValue for EffectVarValue<'tcx> { - type Error = (EffectVarValue<'tcx>, EffectVarValue<'tcx>); + type Error = NoError; fn unify_values(value1: &Self, value2: &Self) -> Result { - match (value1, value2) { - (EffectVarValue::Host, EffectVarValue::Host) => Ok(EffectVarValue::Host), - (EffectVarValue::NoHost, EffectVarValue::NoHost) => Ok(EffectVarValue::NoHost), - (EffectVarValue::NoHost | EffectVarValue::Host, _) - | (_, EffectVarValue::NoHost | EffectVarValue::Host) => Err((*value1, *value2)), - (EffectVarValue::Const(_), EffectVarValue::Const(_)) => { - bug!("equating two const variables, both of which have known values") + match (*value1, *value2) { + (EffectVarValue::Unknown, EffectVarValue::Unknown) => Ok(EffectVarValue::Unknown), + (EffectVarValue::Unknown, EffectVarValue::Known(val)) + | (EffectVarValue::Known(val), EffectVarValue::Unknown) => { + Ok(EffectVarValue::Known(val)) + } + (EffectVarValue::Known(_), EffectVarValue::Known(_)) => { + bug!("equating known inference variables: {value1:?} {value2:?}") } } } @@ -229,7 +233,7 @@ impl<'tcx> UnifyValue for EffectVarValue<'tcx> { #[derive(PartialEq, Copy, Clone, Debug)] pub struct EffectVidKey<'tcx> { pub vid: ty::EffectVid, - pub phantom: PhantomData>, + pub phantom: PhantomData>, } impl<'tcx> From for EffectVidKey<'tcx> { @@ -239,7 +243,7 @@ impl<'tcx> From for EffectVidKey<'tcx> { } impl<'tcx> UnifyKey for EffectVidKey<'tcx> { - type Value = Option>; + type Value = EffectVarValue<'tcx>; #[inline] fn index(&self) -> u32 { self.vid.as_u32()