As some drive-by's:
* moved bitwise operators into `mod bitslice`
* factored out `fn gen` and `fn kill` methods on `BlockSets` type
* removed outdated comment about `fn propagate_call_return`
* removed `on_all_children_bits`, rewriting calls to use `super::on_all_children_bits`
* moved `fn path` helper routine out of `impl MirBorrowckCtxtPreDataflow`
(The static semantics of `rustc_peek` is derived from attributes
attached to the function being compiled; in this case,
`rustc_peek(&expr)` observes the dataflow state for the l-value
`expr`.)
Incorporates many fixes contributed by arielb1.
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revise borrowck::mir::dataflow code to allow varying domain for bitvectors.
This particular code implements the `BitDenotation` trait for three
analyses:
* `MovingOutStatements`, which, like `borrowck::move_data`, maps each
bit-index to a move instruction, and a 1 means "the effect of this
move reaches this point" (and the assigned l-value, if a scoped
declaration, is still in scope).
* `MaybeInitializedLvals`, which maps each bit-index to an l-value.
A 1 means "there exists a control flow path to this point that
initializes the associated l-value."
* `MaybeUninitializedLvals`, which maps each bit-index to an l-value
A 1 means "there exists a control flow path to this point that
de-initializes the associated l-value."
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Revised `graphviz` dataflow-rendering support in `borrowck::mir`.
One big difference is that this code is now parameterized over the
`BitDenotation`, so that it can be used to render dataflow results
independent of how the dataflow bitvectors are interpreted; see where
reference to `MoveOut` is replaced by the type parameter `D`.
----
Factor out routine to query subattributes in `#[rustc_mir(..)]`.
(Later commits build upon this for some unit testing and instrumentation.)
----
thread through a tcx so that I can query types of lvalues as part of analysis.
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Revised `BitDenotation::Ctxt`, allowing variation beyond `MoveData`.
The main motivation is to ease threading through a `TyCtxt`.
(In hindsight it might have been better to instead attach the `TyCtxt`
to each of the different dataflow implementations, but that would
require e.g. switching away from having a `Default` impl, so I am
leaving that experiment for another time.)
(The crucial thing these changes are working toward (but are not yet
in this commit) is a way to pretty-print MIR without having the
`NodeId` for that MIR in hand.)
Batch of improvements to errors for new error format
This is a batch of improvements to existing errors to help get the most out of the new error format.
* Added labels to primary spans (^^^) for a set of errors that didn't currently have them
* Highlight the source blue under the secondary notes for better readability
* Move some of the "Note:" into secondary spans+labels
* Fix span_label to take &mut instead, which makes it work the same as other methods in that set
