Clean up a few general patterns that are now obviated by canImport
This aligns more generally with the cleanup that the Swift Package
Manager has already done in their automated XCTest-plumbing tool in
apple/swift-package-manager#1826.
* Benchmark {Float,Double,Float80}.description
This just tests how fast we can format the standard
floating-point types. It also includes a test that
uses the result, to ensure that future optimized
_creation_ of the string doesn't incidentally pessimize
_use_ of the results.
* Benchmark {Float,Double,Float80}.description
This just tests how fast we can format the standard
floating-point types. It also includes a test that
uses the result, to ensure that future optimized
_creation_ of the string doesn't incidentally pessimize
_use_ of the results.
* Add benchmarks for values close to 1 + other review suggestions