Make `init(catching:)` and `get()` use typed throws. The former infers
the `Failure` type from the closure provided (once full type inference
is in place) and the latter only throws errors of the `Failure` type.
These are provided for FixedWidthInteger & UnsignedInteger (the base implementation, following Knuth's Algorithm D) and SignedInteger (converting to magnitudes and calling the former). Previously no default implementations were available, requiring every type to implement these operations.
These defaults will not be optimal for large fixed-width integers, so types vending Int512 or similar integers should still provide their own implementations, but they are unconditionally available as a fallback, which simplifies the process of writing such types, and work well enough as a fallback for modest fixed-width integer types like Int64 or 32b or smaller platforms or Int128 on 64b platforms.
Additionally rework the concrete implementations to guarantee that we always trap when the quotient is not representable, and to improve performance for 64b integers on arm64_32, and added some new test coverage for these operations.
These class methods are internal, but because they are overridden and are
part of a `@usableFromInline`, `@_fixed_layout` class, we they can't be
moved over to typed throws without breaking ABI. However, they are
only ever called from typed-throws functions, which already need a
do...catch dance to downcast the error itself. Make them `throws`
instead, which is ABI-compatible, but eliminates the need for
do...catch hackery in the function itself.
Replace the hackish use of `@_disfavoredOverload` with the more principled
use of `@_silgen_name` for the entrypoint we are maintaining, then rename
these functions in source to `__rethrows_map` to indicate what they're for.
While here, make them `throws` instead of `rethrows`. The ABI is the
same, and `throws` allows us do avoid to do/catch tricks with rethrows
functions.
Adopt typed throws for the `map` operation to propagate thrown error
types through the `map` API. This is done in a manner that is backward
compatible for almost all cases:
* The new typed-throws entrypoint is `@_alwaysEmitIntoClient` so it
can back-deploy all the way back.
* The old `rethrows` entrypoint is left in place, using
`@usableFromInline` with `internal` so it is part of the ABI but not
the public interface, and `@_disfavoredOverload` so the type checker
avoids it while building the standard library itself. The old
entrypoint is implemented in terms of the new one.
Note that the implementation details for the existential collection
"box" classes rely on method overriding of `_map` operations, and the
types are frozen, so we don't get to change their signatures. However,
these are only implementations, not API: the actual API `map`
functions can be upgraded to typed throws.
Note that this code makes use of a known hole in `rethrows` checking
to allow calling between `rethrows` and typed throws. We'll need to do
something about this for source-compatibility reasons, but I'll follow
up with that separately.
When building the stdlib with noncopyable generics enabled,
requirements for Copyable and Escapable end up being inferred on the
protocols Copyable and Escapable, themselves. So we need to opt-out
Copyable from requiring Escapable, and vice versa.
* Adds RangeSet/DiscontiguousSlice to the stdlib
* Remove redundant DiscontiguousSlice.Index: Comparable conformance
* Attempt to fix embedded build
* Attempt to fix macOS test failures
* Fix Constaints/members.swift failure on linux
* Add exceptions to ABI/source checker to fix macOS tests
* Fix incremental dependency test failure
* Remove inlining/unfreeze implementation for future improvements
* Simplify indices(where:) implementation
* Address review feedback
* Add test for underscored, public slice members
* Address feedback on inlining, hashing, and initializing with unordered arrays
* Fix ABI checker issues
* Remove MutableCollection extension for DiscontiguousSlice
* Make insertion return a discardable Bool
* Fix ABI checker tests
* Fix other ABI checker tests due to dropping MutableCollection subscript
This means that we'll end up going int32 -> int64 -> float/double sometiems, but LLVM knows how to optimize away the intermediate conversion so we end up with just a normal 32b->float conversion as desired, and we get much, much better performance on oddball platforms like arm64_32.
The `_diagnoseUnavailableCodeReached()` function was introduced in the Swift
5.9 standard library and employs `@backDeployed` to support compilation of
binaries that target OS releases aligned with earlier Swift releases.
Unfortunately, though, this backdeployment strategy doesn't work well for some
unusual build environments. Specifically, in some configurations code may be
built with a compiler from a recent Swift toolchain and then linked against the
dylibs in an older toolchain. When linking against the older dylibs, the
`_diagnoseUnavailableCodeReached()` function does not exist but the
`@backDeployed` thunks emitted into the binary reference that function and
therefore linking fails.
The idea of building with one toolchain and then linking to the dylibs in a
different, older toolchain is extremely dubious. However, it exists and for now
we need to support it. This PR introduces an alternative
`_diagnoseUnavailableCodeReached()` function that is annotated with
`@_alwaysEmitIntoClient`. Calls to the AEIC variant are now emitted by the
compiler when the deployment target is before Swift 5.9.
Once these unusual build environments upgrade and start linking against a Swift
5.9 toolchain or later we can revert all of this.
Resolves rdar://119046537
The SIL printer is printing opaque parameters as <anonymous>, which
breaks the SIL parser. Stop using opaque parameters in the standard
library for the moment to unbreak SIL parsing of the standard library.
