Commit the platform definition and build script work necessary to
cross-compile for arm64_32.
arm64_32 is a variant of AARCH64 that supports an ILP32 architecture.
Windows uses `char *` for the `va_list` type even on x86_64. Restore
the correct selection of `__VaListBuilder` for Windows x86_64. This
partially fixes variadic functions.
This refactoring uses large portions of the already existing code for
x86_64 and s390 to implement AAPCS64 __VaListBuilder. The parts where
each implementation differ are the x86_64 header, and the order of the
general and vector registers.
The changes also addresses many of the request from the reviewers in
#20862 which were not addressed originally, like the reuse of the
already existing code, and the generalizations for the code to be useful
for platforms different than Linux (Android, for example).
When I added support for importing long double as Float80 on Intel, I neglected to conform it to CVarArgs. This patch fixes that, which most importantly lets users use String(format:) with Float80 values.
Rename some of the variables in the VaListBuilder path to be agnostic to
the architecture. SSE is x86 specific, by renaming the variables to
hide the fact that the path is x86 specific, we will be able to share
some of the code with arm64 (where the analogous hardware is the VFP).
This includes various revisions to the APIs landing in Swift 4.2, including:
- Random and other randomness APIs
- Hashable changes
- MemoryLayout.offset(of:)
The resilience model forces inlinable code to use resiliently conservative access paths for properties in the same module, but some stdlib methods by design escapes storage of a global variable. The additional `Builtin.addressof` validation introduced in #15608 exposed the latent issue here.
This changes the conditional for the definition of the _VaListBuilder.
This makes it easier to read as well as to extend to other platforms
which use a non-pointer va_list type. NFC.
- Revisions to unsafeDowncast and withVaList
- Fix the Int64/UInt64 discussion
- Buffer pointer revisions
- Fix Optional example to use new integer methods
- Revise and correct some UnsafeRawBufferPointer docs
- Fix symmetricDifference examples
- Fix wording in FloatingPoint.nextDown
- Update ImplicitlyUnwrappedOptional
- Clarify elementsEqual
- Minor integer doc fixes
- Comment for _AppendKeyPath
- Clarification re collection indices
- Revise RangeExpression.relative(to:)
- Codable revisions
- remove additional 'characters' references from String docs
- improved language around escaping pointer arguments
- key path type abstracts
- codable type abstract revisions
- a few more NSString API fixes
From the Swift documentation:
"If you define an optional variable without providing a default value,
the variable is automatically set to nil for you."
