Teach isClangTypeMoreIndirectThanSubstType about swift_newtype-ed
typedefs, which may be of CF foreign class type. In these cases, we
should reason about the underlying, wrapped type. Includes
refactoring of common logic and tests.
Several functionalities have been added to FSO over time and the logic has become
muddled.
We were always looking at a static image of the SIL and try to reason about what kind of
function signature related optimizations we can do.
This can easily lead to muddled logic. e.g. we need to consider 2 different function
signature optimizations together instead of independently.
Split 1 single function to do all sorts of different analyses in FSO into several
small transformations, each of which does a specific job. After every analysis, we produce
a new function and eventually we collapse all intermediate thunks to in a single thunk.
With this change, it will be easier to implement function signature optimization as now
we can do them independently now.
Minimal modifications to the test cases.
Allow it to have undef as an operand.
This can happen when NoReturnFolding does RAUW for the instructions that
come after a @noreturn function, replacing the uses of those
instructions in blocks that are unreachable. These instructions end up
getting deleted during diagnose unreachable when we remove the
unreachable code.
Fixes SR-967 / rdar://problem/25882880.
This made call sites confusing to read because it doesn't actually
check if the function already exists.
Also fix some minor formatting issues. This came up while I was working
on a fix for a bug that turned out to not be a bug.
It it now possible to check if a function with a given name and a given linkage exists in one of the modules,
even if the current module contains a function with this name but a difference linkage.
This is useful e.g. for performing a lookup of pre-specializations.
Implements SE-0055: https://github.com/apple/swift-evolution/blob/master/proposals/0055-optional-unsafe-pointers.md
- Add NULL as an extra inhabitant of Builtin.RawPointer (currently
hardcoded to 0 rather than being target-dependent).
- Import non-object pointers as Optional/IUO when nullable/null_unspecified
(like everything else).
- Change the type checker's *-to-pointer conversions to handle a layer of
optional.
- Use 'AutoreleasingUnsafeMutablePointer<NSError?>?' as the type of error
parameters exported to Objective-C.
- Drop NilLiteralConvertible conformance for all pointer types.
- Update the standard library and then all the tests.
I've decided to leave this commit only updating existing tests; any new
tests will come in the following commits. (That may mean some additional
implementation work to follow.)
The other major piece that's missing here is migration. I'm hoping we get
a lot of that with Swift 1.1's work for optional object references, but
I still need to investigate.
Previously IRGen would force all fragile entities to have public linkage.
It makes more sense to do this in SILGen instead, and only when
-sil-serialize-all is on.
This patch was previously committed and reverted; the optimizer
issues exposed by the original version should now be fixed.
Two fixes to optimization passes to maintain restrictions about what
[fragile] functions can reference:
- When devirtualizing witness methods, don't devirtualize if the caller
is fragile and the callee is not. This matches existing logic in
class devirtualization.
- When performing generic or function signature specialization, don't
specialize non-fragile functions referenced from fragile functions.
Since @_transparent functions are allowed to call 'static inline'
imported functions, also be sure to mark the foreign-to-native thunk
for such a function as [fragile].
With this patch, the standard library and performance test suite
now build with -enable-resilience.
No new tests for this stuff here -- the existing tests together
with an -enable-resilience build provide coverage.
Closes out <https://bugs.swift.org/browse/SR-267> and
<https://bugs.swift.org/browse/SR-268>.
Change the optimizer to only make specializations [fragile] if both the
original callee is [fragile] *and* the caller is [fragile].
Otherwise, the specialized callee might be [fragile] even if it is never
called from a [fragile] function, which inhibits the optimizer from
devirtualizing calls inside the specialization.
This opens up some missed optimization opportunities in the performance
inliner and devirtualization, which currently reject fragile->non-fragile
references:
TEST | OLD_MIN | NEW_MIN | DELTA (%) | SPEEDUP
--- | --- | --- | --- | ---
DictionaryRemoveOfObjects | 38391 | 35859 | -6.6% | **1.07x**
Hanoi | 5853 | 5288 | -9.7% | **1.11x**
Phonebook | 18287 | 14988 | -18.0% | **1.22x**
SetExclusiveOr_OfObjects | 20001 | 15906 | -20.5% | **1.26x**
SetUnion_OfObjects | 16490 | 12370 | -25.0% | **1.33x**
Right now, passes other than performance inlining and devirtualization
of class methods are not checking invariants on [fragile] functions
at all, which was incorrect; as part of the work on building the
standard library with -enable-resilience, I added these checks, which
regressed performance with resilience disabled. This patch makes up for
these regressions.
Furthermore, once SIL type lowering is aware of resilience, this will
allow the stack promotion pass to make further optimizations after
specializing [fragile] callees.
Always statically dispatch to C functions imported as members, and
call to the foreign entry point. This gets us through SILGen, but DI
is still deeply unhappy with the resulting SIL.
Bridging thunks don't yet support bridging address-only types, but
ideally they should, so that we can bridge Objective-C types to
resilient value types.
This came up while I was adding @_fixed_layout declarations in
the standard library. To make this easier to figure out in the
future, add the asserts to the bridging logic for now.
Also, to avoid hitting the asserts when we emit a reference to a
C function with an incompatible type, don't emit the foreign
function at all until we determine that the ABI conversion is safe.
Previously IRGen would force all fragile entities to have public linkage.
It makes more sense to do this in SILGen instead, and only when
-sil-serialize-all is on.
If a function is public, and either @_transparent or @inline(__always),
we need to make its body available for inlining in other resilience
domains. The more general concept here is an 'inlineable' function;
once the precise behaviors we want are nailed down, the set of AST
attributes for exposing this will likely change.
At the SIL level, inlineable functions are marked with the [fragile]
attribute. The SIL serializer only serializes [fragile] functions
unless -sil-serialize-all is passed in.
This patch fixes two problems in this area by consolidating some
duplicated logic:
1) Property accesses in Sema did not check for @inline(__always)
functions, or functions nested inside inlineable functions.
This manifested as IRGen crashes if an inlineable function
accessed a property of a resilient type.
2) In SILGen, functions nested inside [fragile] functions were
properly [fragile], but @inline(__always) was not taken into
account. This manifested as SIL serializer crashes where a
[fragile] function could reference a non-public, non-[fragile]
function.
This change is part of the series for building the standard library
without -sil-serialize-all.
This attribute is a stand-in for the versioning annotations
described in docs/LibraryEvolution.rst; right now it's just present
or absent, and its only effect is to make sure versioned internal
decls are treated as public at the SIL level. (This functionality
already existed for -enable-testing, so it can probably be trusted.)
Also, allow inlineable functions to reference transparent and
inline-always functions /if/ they're only called immediately (not used
as values or partial-applied), since they'll be inlined away before
emitting IR. (We should really only allow this /before/ mandatory
inlining, but we don't have a separate SIL stage for that.)
If a thunk is referenced from two different functions, the thunk inherits
the fragile attribute from the first function that forced it to be emitted.
This is wrong, in case the first function might not be fragile, while
the second one is. Copying the fragile attribute to an existing thunk when
checking if it has already been emitted is also wrong, because the thunk
might reference another thunk, and so on.
The correct fix is to have SIL serialization serialize the transitive
closure of all fragile functions and thunks referenced from fragile
functions. Re-work SIL function serialization to use a worklist so that
we can do this.
Part of https://bugs.swift.org/browse/SR-267.
A transparent function might be deserialized and inlined into a function
in another module, which would cause problems if the function referenced
local functions.
Previously we would force local functions to have public linkage instead,
which worked, but was not resilient if the body of the transparent
function changed in the module that contained it.
Add a library evolution test ensuring that such a change is resilient
now.
Part of https://bugs.swift.org/browse/SR-267.