We sometimes see expression type checking times increase dramatically
when this is enabled, and having a way to disable will make it
possible to easily do measurements to determine the cost/benefit of
having this enabled.
As a debugging aid, introduce a new frontend flag `-debug-cycles` that
will emit a debug dump whenever the request-evaluator encounters a cyclic
dependency, while otherwise allowing compilation to continue.
This work-around is no longer needed now that the full fix landed in
https://github.com/apple/swift/pull/16615. The argument is left with a warning
to help with migration between compilers with the work-around and compilers with
the full fix (see also rdar://problem/40502379).
Fixes rdar://problem/40476573.
IRGen can introduce calls to type metadata accessors for types that
should not be visible to the current translate, which can manifest in
linker errors within a module (for references to private types when
whole module optimization is disabled) or across modules (for
references to private/internal types in another module). Introduce a
new compiler flag `-emit-public-type-metadata-accessors` that emits
all type metadata accessors with public linkage, to work around the
problem in affected projects. This flag is intended to go away once we
have a proper solution.
This bug has been around in Swift "forever", but compiling the
overlays using -enable-resilience has exacerbated the problem and
caused regressions. This is a short-term fix to
rdar://problem/40229755 while we work on the correct long-term fix.
This way we'll link against the key path component the other module provides instead of making fragile assumptions about its current implementation. Since external keypath lowering isn't fully implemented elsewhere in the compiler, this is enabled behind a staging flag.
external keypath staging
Before this patch, we have one flag (KeepSyntaxInfo) to turn on two syntax
functionalities of parser: (1) collecting parsed tokens for coloring and
(2) building syntax trees. Since sourcekitd is the only consumer of either of these
functionalities, sourcekitd by default always enables such flag.
However, empirical results show (2) is both heavier and less-frequently
needed than (1). Therefore, separating the flag to two flags makes more
sense, where CollectParsedToken controls (1) and BuildSyntaxTree
controls (2).
CollectingParsedToken is always enabled by sourcekitd because
formatting and syntax-coloring need it; however BuildSyntaxTree should
be explicitly switched on by sourcekitd clients.
resolves: rdar://problem/37483076
The current implementation isn't really useful in the face of generic
overloads. It has never been enabled by default, and isn't useful to
keep around if it is disabled. If we ever want to bring it back,
we know where to look!
With more syntax nodes being specialized, we'd like this
straight-forward way to pinpoint unknown entities. This diagnostics
is only issued in -emit-syntax frontend action and swift-syntax-test
invocation.
Swift class metadata has a bit to distinguish it from non-Swift Objective-C
classes. The stable ABI will use a different bit so that stable Swift and
pre-stable Swift can be distinguished from each other.
No bits are actually changed yet. Enabling the new bit needs to wait for
other coordination such as libobjc.
rdar://35767811
The original hope was we could make these heuristics really good, but
since that is not currently in sight (and may never be), we want to be
able to turn them off. For now, just plumb through an internal flag to
control the behaviour. A future change will customize the behaviour in
SourceKit.
rdar://31113161
Conditional conformances aren't quite ready yet for Swift 4.1, so
introduce the flag `-enable-experimental-conditional-conformances` to
enable conditional conformaces, and an error when one declares a
conditional conformance without specifying the flag.
Add this flag when building the standard library (which will vend
conditional conformances) and to all of the tests that need it.
Fixes rdar://problem/35728337.
This allows reporting successful and unsuccessful optimizations similar to
clang/llvm.
This first patch adds support for the
options -Rpass=<pass-name-regex> -Rpass-missed=<pass-name-regex>. These allow
reporting successful/unsuccessful optimization on the compiler output for passes
specified by the regex. I've also added one missed and one passed remark type
to the inliner to test the infrastructure.
Clang also has the option of collecting these records in an external YAML data
file. This will be added in a later patch.
A few notes:
* The goal is to use this facility for both user-lever "performance" warnings
and expert-level performance analysis. There will probably be a flag in the
future differentiating the verbosity.
* The intent is match clang/llvm as much as it makes sense. On the other hand I
did make some changes. Unlike in llvm, the emitter is not a pass which
simplifies things. Also the remark class hierarchy is greatly simplified since
we don't derive from DiagnosticInfo. We also don't derive from Diagnostic to
support the streaming API for arbitrary named-value pairs.
* Currently function names are printed mangled which should be fixed.
We've found in practice that multiple different types of expressions
are still going to benefit from shrinking continuing even when it
couldn't simplify up to 10 sub-expressions.
This patch allows Parser to generate a refined token stream to satisfy tooling's need. For syntax coloring, token stream from lexer is insufficient because (1) we have contextual keywords like get and set; (2) we may allow keywords to be used as argument labels and names; and (3) we need to split tokens like "==<". In this patch, these refinements are directly fulfilled through parsing without additional heuristics. The refined token vector is optionally saved in SourceFile instance.
This implementation required a compromise between parser
performance and AST structuring. On the one hand, Parse
must be fast in order to keep things in the IDE zippy, on
the other we must hit the disk to properly resolve 'canImport'
conditions and inject members of the active clause into the AST.
Additionally, a Parse-only pass may not provide platform-specific
information to the compiler invocation and so may mistakenly
activate or de-activate branches in the if-configuration decl.
The compromise is to perform condition evaluation only when
continuing on to semantic analysis. This keeps the parser quick
and avoids the unpacking that parse does for active conditions
while still retaining the ability to see through to an active
condition when we know we're moving on to semantic analysis anyways.
Recently support was added for '-swift-version 5' to the frontend.
Right now we only have an isSwiftVersion3() check which returns 'true'
if the version is 3, and returns 'false' if it is 4 or 5. This was used
during Swift 4.0 development to guard various legacy behaviors that we
wish to deprecate.
Going forward, when do not want to add isSwiftVersion4() and
isSwiftVersion5() checks, because they're too fragile; if a new
behavior is introduced in Swift 5 that we wish to disable in Swift 3
and Swift 4 mode, checking for isSwiftVersion5() is insufficient,
because eventually Swift 6 will roll around, and presumably one would
expect the new behavior to take effect in Swift 6 mode as well.
I think a better solution is a 'isSwiftVersionAtLeast()' check, which
checks if the major version number is greater than or equal to the
given value.
We could refactor the existing 'isSwiftVersion3()' checks to instead
do '!isSwiftVersionAtLeast(4)', but I'm going to hold off on doing that
for now.
Currently we have a number of unsolved disjunctions hard-coded to 5,
which breaks some existing code by terminating shrinking too early.
This patch makes it a command-line option so users have control over
what that threshold can be.
Resolves: rdar://problem/33433595
This reverts commit afbdbae9d9.
Commit ded45a6e1c more than triples the
type checking time when building Swift.o, so I am going to revert that ,
and it looks like this needs to be reverted as well if that commit is
reverted.
Introduce `-enable-recursive-constraints` to disable the error about
direct recursion within a protocol definition. The implementation of
recursive protocol constraints is incomplete, but might be useful for
experimentation.
Typo correction can be particularly expensive, so introduce a
command-line flag to limit the number of typo corrections we will
perform per type-checker instance. Default this limit to 10.
Addresses rdar://problem/28469270 to some extent.
This time, the warnings only fire when the class in question directly
conforms to NSCoding. This avoids warning on cases where the user has
subclassed something like, oh, UIViewController, and has no intention
of writing it to a persistent file.
This also removes the warning for generic classes that conform to
NSCoding, for simplicity's sake. That means
'@NSKeyedArchiverEncodeNonGenericSubclassesOnly' is also being
removed.
Actually archiving a class with an unstable mangled name is still
considered problematic, but the compiler shouldn't emit diagnostics
unless it can be sure they are relevant.
rdar://problem/32314195
Adoption so far shows that the criteria we set up here are too broad.
This is particularly problematic for subclasses of NS/UIView and the
like that might never be encoded at all.
rdar://problem/32306355
This is a bit more robust and user-friendly than hoping more brittle recovery in SILGen or IRGen for unsupported components kicks in. rdar://problem/32200714
