* Revert "Add availability information to the new Math function protocols (#24187)"
This reverts commit d2f695935f.
* Revert "SE-0246: Protocols and static functions (#23824)"
This reverts commit 57a4553832.
* Expected abi changes.
These functions have never actually been supported in Swift, because Swift does not model the dynamic floating point environment. They may have worked occasionally in the past, but that was only accidental. Deprecate them with an explanatory message.
* Add availability information to the new Math function protocols
The protocols ElementaryFunctions, RealFunctions, and Real are new in Swift 5.1 and accordingly need to have availability attached to them for platforms that are ABI-stable. The actual implementation hooks (static functions) are unconditionally defined on scalar types and marked @_alwaysEmitIntoClient, so they are available even when targeting older library versions, but the protocols themselves, and anything defined in terms of them (the global functions and the SIMD extensions) is only available when targeting library versions that have the new protocols.
* Additionally provide concrete implementations of signGamma for each stdlib-builtin floating-point type.
* Remove Real[Functions] protocols pending re-review
Temporarily pull these back so we can make minor tweaks to the design and get a re-review on SE.
This implements the protocols and static functions proposed in SE-0246, plus some initial test coverage. It also has some rough accompanying cleanup of tgmath. It does not include the globals (on scalars or SIMD types) nor does it deprecate much in tgmath.h.
* Revert "Merge pull request #23791 from compnerd/you-know-nothing-clang"
This reverts commit 5150981150, reversing
changes made to 8fc305c03e.
* Revert "Merge pull request #23780 from compnerd/math-is-terrible"
This reverts commit 2d7fedd25f, reversing
changes made to 0205150b8f.
* Revert "Merge pull request #23140 from stephentyrone/mafs"
This reverts commit 777750dc51, reversing
changes made to 0c8920e747.
This commit implements SE-0246, by adding conformance to Real to the Float, CGFloat, Double, and Float80 types, implemented either in terms of the system's C math library, existing standard library functionality, or LLVM intrinsics. It includes basic test coverage for these new functions, and deprecates and obsoletes *some* existing functionality in the Platform overlay. We still need to make a decision about how to handle the remaining "tgmath" functions, because obsoleting them is technically a source-breaking change (if users have unqualified names like "exp(1)", it's fine, but it would break users who have used qualified names like "Darwin.exp(1)".)
* Minor improvements to CGFloat
Apparently init(exactly:) was never implemented for CGFloat, so let's fix that. Also includes minor cleanup for the .magnitude property.
* Add transparent annotations to some other CGFloat things.
The SDK directory is now confusing as the Windows target also has a SDK
overlay. In order to make this more uniform, move the SDK directory to
Darwin which covers the fact that this covers the XNU family of OSes.
The Windows directory contains the SDK overlay for the Windows target.
