diff options
Diffstat (limited to 'src/librustc/ty/mod.rs')
| -rw-r--r-- | src/librustc/ty/mod.rs | 150 |
1 files changed, 89 insertions, 61 deletions
diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs index c9e58b6c771..b25fd3c61fd 100644 --- a/src/librustc/ty/mod.rs +++ b/src/librustc/ty/mod.rs @@ -515,79 +515,107 @@ pub struct CReaderCacheKey { pub pos: usize, } -// Flags that we track on types. These flags are propagated upwards -// through the type during type construction, so that we can quickly -// check whether the type has various kinds of types in it without -// recursing over the type itself. bitflags! { + /// Flags that we track on types. These flags are propagated upwards + /// through the type during type construction, so that we can quickly check + /// whether the type has various kinds of types in it without recursing + /// over the type itself. pub struct TypeFlags: u32 { - const HAS_PARAMS = 1 << 0; - const HAS_TY_INFER = 1 << 1; - const HAS_RE_INFER = 1 << 2; - const HAS_RE_PLACEHOLDER = 1 << 3; - - /// Does this have any `ReEarlyBound` regions? Used to - /// determine whether substitition is required, since those - /// represent regions that are bound in a `ty::Generics` and - /// hence may be substituted. - const HAS_RE_EARLY_BOUND = 1 << 4; - - /// Does this have any region that "appears free" in the type? - /// Basically anything but `ReLateBound` and `ReErased`. - const HAS_FREE_REGIONS = 1 << 5; - - /// Is an error type reachable? - const HAS_TY_ERR = 1 << 6; - const HAS_PROJECTION = 1 << 7; - - // FIXME: Rename this to the actual property since it's used for generators too - const HAS_TY_CLOSURE = 1 << 8; + // Does this have parameters? Used to determine whether substitution is + // required. + /// Does this have [Param]? + const HAS_TY_PARAM = 1 << 0; + /// Does this have [ReEarlyBound]? + const HAS_RE_PARAM = 1 << 1; + /// Does this have [ConstKind::Param]? + const HAS_CT_PARAM = 1 << 2; + + const NEEDS_SUBST = TypeFlags::HAS_TY_PARAM.bits + | TypeFlags::HAS_RE_PARAM.bits + | TypeFlags::HAS_CT_PARAM.bits; + + /// Does this have [Infer]? + const HAS_TY_INFER = 1 << 3; + /// Does this have [ReVar]? + const HAS_RE_INFER = 1 << 4; + /// Does this have [ConstKind::Infer]? + const HAS_CT_INFER = 1 << 5; + + /// Does this have inference variables? Used to determine whether + /// inference is required. + const NEEDS_INFER = TypeFlags::HAS_TY_INFER.bits + | TypeFlags::HAS_RE_INFER.bits + | TypeFlags::HAS_CT_INFER.bits; + + /// Does this have [Placeholder]? + const HAS_TY_PLACEHOLDER = 1 << 6; + /// Does this have [RePlaceholder]? + const HAS_RE_PLACEHOLDER = 1 << 7; + /// Does this have [ConstKind::Placeholder]? + const HAS_CT_PLACEHOLDER = 1 << 8; /// `true` if there are "names" of types and regions and so forth /// that are local to a particular fn - const HAS_FREE_LOCAL_NAMES = 1 << 9; + const HAS_FREE_LOCAL_NAMES = TypeFlags::HAS_TY_PARAM.bits + | TypeFlags::HAS_RE_PARAM.bits + | TypeFlags::HAS_CT_PARAM.bits + | TypeFlags::HAS_TY_INFER.bits + | TypeFlags::HAS_RE_INFER.bits + | TypeFlags::HAS_CT_INFER.bits + | TypeFlags::HAS_TY_PLACEHOLDER.bits + | TypeFlags::HAS_RE_PLACEHOLDER.bits + | TypeFlags::HAS_CT_PLACEHOLDER.bits; + + /// Does this have [Projection] or [UnnormalizedProjection]? + const HAS_TY_PROJECTION = 1 << 9; + /// Does this have [Opaque]? + const HAS_TY_OPAQUE = 1 << 10; + /// Does this have [ConstKind::Unevaluated]? + const HAS_CT_PROJECTION = 1 << 11; + + /// Could this type be normalized further? + const HAS_PROJECTION = TypeFlags::HAS_TY_PROJECTION.bits + | TypeFlags::HAS_TY_OPAQUE.bits + | TypeFlags::HAS_CT_PROJECTION.bits; /// Present if the type belongs in a local type context. - /// Only set for Infer other than Fresh. - const KEEP_IN_LOCAL_TCX = 1 << 10; - - /// Does this have any `ReLateBound` regions? Used to check - /// if a global bound is safe to evaluate. - const HAS_RE_LATE_BOUND = 1 << 11; + /// Set for placeholders and inference variables that are not "Fresh". + const KEEP_IN_LOCAL_TCX = 1 << 12; - /// Does this have any `ReErased` regions? - const HAS_RE_ERASED = 1 << 12; + /// Is an error type reachable? + const HAS_TY_ERR = 1 << 13; - const HAS_TY_PLACEHOLDER = 1 << 13; + /// Does this have any region that "appears free" in the type? + /// Basically anything but [ReLateBound] and [ReErased]. + const HAS_FREE_REGIONS = 1 << 14; - const HAS_CT_INFER = 1 << 14; - const HAS_CT_PLACEHOLDER = 1 << 15; - /// Does this have any [Opaque] types. - const HAS_TY_OPAQUE = 1 << 16; + /// Does this have any [ReLateBound] regions? Used to check + /// if a global bound is safe to evaluate. + const HAS_RE_LATE_BOUND = 1 << 15; - const NEEDS_SUBST = TypeFlags::HAS_PARAMS.bits | - TypeFlags::HAS_RE_EARLY_BOUND.bits; + /// Does this have any [ReErased] regions? + const HAS_RE_ERASED = 1 << 16; /// Flags representing the nominal content of a type, /// computed by FlagsComputation. If you add a new nominal /// flag, it should be added here too. - const NOMINAL_FLAGS = TypeFlags::HAS_PARAMS.bits | - TypeFlags::HAS_TY_INFER.bits | - TypeFlags::HAS_RE_INFER.bits | - TypeFlags::HAS_RE_PLACEHOLDER.bits | - TypeFlags::HAS_RE_EARLY_BOUND.bits | - TypeFlags::HAS_FREE_REGIONS.bits | - TypeFlags::HAS_TY_ERR.bits | - TypeFlags::HAS_PROJECTION.bits | - TypeFlags::HAS_TY_CLOSURE.bits | - TypeFlags::HAS_FREE_LOCAL_NAMES.bits | - TypeFlags::KEEP_IN_LOCAL_TCX.bits | - TypeFlags::HAS_RE_LATE_BOUND.bits | - TypeFlags::HAS_RE_ERASED.bits | - TypeFlags::HAS_TY_PLACEHOLDER.bits | - TypeFlags::HAS_CT_INFER.bits | - TypeFlags::HAS_CT_PLACEHOLDER.bits | - TypeFlags::HAS_TY_OPAQUE.bits; + const NOMINAL_FLAGS = TypeFlags::HAS_TY_PARAM.bits + | TypeFlags::HAS_RE_PARAM.bits + | TypeFlags::HAS_CT_PARAM.bits + | TypeFlags::HAS_TY_INFER.bits + | TypeFlags::HAS_RE_INFER.bits + | TypeFlags::HAS_CT_INFER.bits + | TypeFlags::HAS_TY_PLACEHOLDER.bits + | TypeFlags::HAS_RE_PLACEHOLDER.bits + | TypeFlags::HAS_CT_PLACEHOLDER.bits + | TypeFlags::HAS_TY_PROJECTION.bits + | TypeFlags::HAS_TY_OPAQUE.bits + | TypeFlags::HAS_CT_PROJECTION.bits + | TypeFlags::KEEP_IN_LOCAL_TCX.bits + | TypeFlags::HAS_TY_ERR.bits + | TypeFlags::HAS_FREE_REGIONS.bits + | TypeFlags::HAS_RE_LATE_BOUND.bits + | TypeFlags::HAS_RE_ERASED.bits; } } @@ -1816,10 +1844,10 @@ impl<'tcx> ParamEnv<'tcx> { Reveal::UserFacing => ParamEnvAnd { param_env: self, value }, Reveal::All => { - if value.has_placeholders() || value.needs_infer() || value.has_param_types() { - ParamEnvAnd { param_env: self, value } - } else { + if value.is_global() { ParamEnvAnd { param_env: self.without_caller_bounds(), value } + } else { + ParamEnvAnd { param_env: self, value } } } } |