Changes compared to the original version:
I fixed the 2 bugs and added a test for the so far undetected missing range check bug.
To keep the SIL simple (4 basic blocks for arr[x]) I extracted the slow path for getElement into a
non-inlinable function.
On the other hand I inlined _typeCheck into the slow-path function.
This speeds up NSArray accesses because now only a single objectAtIndex is required for both
type checking and element retrieving.
Update on performance: DeltaBlue is now only 12% better (and not 25%). I suspect this is because
now Arnold's tail duplication cannot detect the ObjC call in the slow path.
Swift SVN r26935
Now that we can check isNative and NoDTC (no deffered type check needed) with a single bit-mask operation,
it makes sense to have a single array property call for it.
I replaced the the semantics call array.props.needsElementTypeCheck with array.props.isNativeNoDTC,
which is the combination of isNative && !needsElementTypeCheck. I kept array.props.isNative, which is not used for now,
but might be useful in the future, e.g. for array operations which don't care about type checks.
The optimized SIL for a class array access arr[i] now contains the minimum of 4 basic blocks.
PerfTests show +25% for DeltaBlue and some improvemements for -Onone.
Swift SVN r26871
We used to handle deferred type-checking by treating down-casted native
array buffers as NSArrays (which they are, but we know more). Instead,
we now save a bit that indicates deferred type-checking is needed and
remember that the buffer is native, which saves dispatching through
objc_MsgSend.
Fixes <rdar://problem/19302286> down-casted Arrays are inefficient
Swift SVN r25472
Previously the "as" keyword could either represent coercion or or forced
downcasting. This change separates the two notions. "as" now only means
type conversion, while the new "as!" operator is used to perform forced
downcasting. If a program uses "as" where "as!" is called for, we emit a
diagnostic and fixit.
Internally, this change removes the UnresolvedCheckedCastExpr class, in
favor of directly instantiating CoerceExpr when parsing the "as"
operator, and ForcedCheckedCastExpr when parsing the "as!" operator.
Swift SVN r24253
Doing so is safe even though we have mock SDK. The include paths for
modules with the same name in the real and mock SDKs are different, and
the module files will be distinct (because they will have a different
hash).
This reduces test runtime on OS X by 30% and brings it under a minute on
a 16-core machine.
This also uncovered some problems with some tests -- even when run for
iOS configurations, some tests would still run with macosx triple. I
fixed the tests where I noticed this issue.
rdar://problem/19125022
Swift SVN r23683
We're going to replace StdlibUnittest's use of ContiguousArray with
_UnitTestArray so that we can work on (and potentially break)
_ContiguousArray and still get useful test results. When refactoring is
complete, we can optionally replace StdlibUnittest's use of
_UnitTestArray with ContiguousArray, or move the decoupled component
into the StdlibUnittest module.
Swift SVN r22874
This decreases total testing time by over a minute on my old Mac Pro.
It probably has much less effect on systems with fewer cores, but shouldn't
be any worse there.
Swift SVN r22745
