Previously, it was possible to write Unsafe[Mutable]Pointer(x) and have
Swift deduce the pointee type based on context. Since reinterpreting
memory is a fundamentally type-unsafe operation, it's better to be
explicit about conversions from Unsafe[Mutable]Pointer<T> to
Unsafe[Mutable]Pointer<U>. This change is consistent with the move from
reinterpretCast(x) to unsafeBitCast(x, T.self).
Also, we've encoded the operations of explicitly adding or removing
mutability as properties, so that adding mutability can be separated
from wild reinterpretCast'ing, a much more severe form of unsafety.
Swift SVN r21324
This allows UnicodeScalars to be constructed from an integer, rather
then from a string. Not only this avoids an unnecessary memory
allocation (!) when creating a UnicodeScalar, this also allows the
compiler to statically check that the string contains a single scalar
value (in the same way the compiler checks that Character contains only
a single extended grapheme cluster).
rdar://17966622
Swift SVN r21198
Now that CGFloat is its own distinct type, it's useful to have Double
initializers to go along with the Int initializers we added a while
back <rdar://problem/17224725>.
Swift SVN r21156
This function mixes the bits in the hash value, which improves Dictionary
performance for keys with bad hashes.
PrecommitBenchmark changes with greater than 7% difference:
``````````Dictionary2`,```1456.00`,```1508.00`,```1502.00`,````624.00`,````607.00`,````592.00`,`864.00`,``145.9%
``````````Dictionary3`,```1379.00`,```1439.00`,```1408.00`,````585.00`,````567.00`,````552.00`,`827.00`,``149.8%
````````````Histogram`,````850.00`,````849.00`,````851.00`,```1053.00`,```1049.00`,```1048.00`,`199.00`,``-19.0%
````````````````Prims`,```1999.00`,```2005.00`,```2018.00`,```1734.00`,```1689.00`,```1701.00`,`310.00`,```18.4%
``````````StrSplitter`,```2365.00`,```2334.00`,```2316.00`,```1979.00`,```1997.00`,```2000.00`,`337.00`,```17.0%
```````````````TwoSum`,```1551.00`,```1568.00`,```1556.00`,```1771.00`,```1741.00`,```1716.00`,`165.00`,```-9.6%
Regressions are in benchmarks that use `Int` as dictionary key: we are just
doing more work than previously (hashing an `Int` was an identity function).
rdar://17962402
Swift SVN r21142
The test harness now can recover after test crashes, allowing:
- check for crashes themselves (without reporting them to the Python lit driver,
which is about 10x slower -- even if CrashTracer is disabled);
- recover from unexpected test crashes and run the rest of the tests;
- this lays the groundwork for assertions that end the test execution, but
allow the rest of the tests to run (rdar://17906801).
Note that we don't spawn a fresh process for every test. We create a child
process and reuse it until it crashes.
Swift SVN r21090