- Rename StepLimit to MaxRuleCount, DepthLimit to MaxRuleLength
- Rename command line flags to -requirement-machine-max-rule-{count,length}=
- Check limits outside of PropertyMap::buildPropertyMap()
- Simplify the logic in RequirementMachine::computeCompletion()
A scoped-down version of #39307. Implement extension of bound generic types. The important bit here is in TypeCheckGeneric where we now use the underlying type of a typealias and its associated nominal type decl when we're generating substitutions for the extended type.
Put this behind a new experimental flag
-enable-experimental-bound-generic-extensions
Resolves SR-4875
Resolves rdar://17434633
Replace the existing `-enable-experimental-clang-importer-diagnostics`
flag with an opt-out version entitled `-disable-experimentalc-clang-importer-diagnostics`.
Enable the beviour previously hidden behind the old flag by default.
Allow a user-defined `buildBlock(combining:into:)` to combine subexpressions in a block pairwise top to bottom. To use `buildBlock(_combining:into:)`, the user also needs to provide a unary `buildBlock(_:)` as a base case. The feature is being gated under frontend flag `-enable-experimental-pairwise-build-block`.
This will enable use cases in `RegexBuilder` in experimental declarative string processing, where we need to concatenate tuples and conditionally skip captureless regexes. For example:
```swift
let regex = Regex {
"a" // Regex<Substring>
OneOrMore("b").capture() // Regex<(Substring, Substring)>
"c" // Regex<Substring>
Optionally("d".capture()) // Regex<(Substring, Substring?)>
} // Regex<Tuple3<Substring, Substring, Substring?>>
let result = "abc".firstMatch(of: regex)
// MatchResult<(Substring, Substring, Substring?)>
```
In this example, patterns `"a"` and `"c"` have no captures, so we need to skip them. However with the existing result builder `buildBlock()` feature that builds a block wholesale from all subexpressions, we had to generate `2^arity` overloads accounting for any occurrences of captureless regexes. There are also other complexities such as having to drop-first from the tuple to obtain the capture type. Though these features could in theory be supported via variadic generics, we feel that allowing result builders to pairwise combine subexpressions in a block is a much simpler and potentially more useful approach.
With `buildBlock(_combining:into:)`, the regex builders can be defined as the following, assuming we have variadic generics:
```swift
enum RegexBuilder {
static func buildBlock() -> Regex<Substring>
static func buildBlock<Match>(_ x: Regex<Match>) -> Regex<Match>
static func buildBlock<
ExistingWholeMatch, NewWholeMatch, ExistingCaptures..., NewCaptures...
>(
_combining next: Regex<(NewWholeMatch, NewCaptures...)>,
into combined: Regex<(ExistingWholeMatch, ExistingCaptures...)>
) -> Regex<Substring, ExistingCaptures..., NewCaptures...>
}
```
Before we have variadic generics, we can define overloads of `buildBlock(_combining:into:)` for up to a certain arity. These overloads will be much fewer than `2^arity`.
This patch introduces new diagnostics to the ClangImporter to help
explain why certain C, Objective-C or C++ declarations fail to import
into Swift. This patch includes new diagnostics for the following entities:
- C functions
- C struct fields
- Macros
- Objective-C properties
- Objective-C methods
In particular, notes are attached to indicate when any of the above
entities fail to import as a result of refering an incomplete (only
forward declared) type.
The new diangostics are hidden behind two new flags, -enable-experimental-clang-importer-diagnostics
and -enable-experimental-eager-clang-module-diagnostics. The first flag emits diagnostics lazily,
while the second eagerly imports all declarations visible from loaded Clang modules. The first
flag is intended for day to day swiftc use, the second for module linting or debugging the importer.
Replaced the -disable-copy-propagation flag with
-enable-copy-propagation=false where the latter is a new multi-var
-enable-copy-propagation= which can take one of three values:
- true
- requested-passes-only
- false
The effect of passing -enable-copy-propagation is both to enable the
CopyPropagation pass to shorten object lifetimes and also to enable
lexical lifetimes to ensure that object lifetimes aren't shortened while
a variable is still in scope and used.
Add a new flag, -enable-lexical-borrow-scopes=true to override
-enable-copy-propagation's effect (setting it to ::ExperimentalLate) on
SILOptions::LexicalLifetimes that sets it to ::Early even in the face of
-enable-copy-propagation. The old flag -disable-lexical-lifetimes is
renamed to -enable-lexical-borrow-scopes=false but continues to set that
option to ::Off even when -enable-copy-propagation is passed.
Previously, both swift-frontend and sil-opt put lexical lifetimes behind
a flag named -enable-experimental-lexical-lifetimes. That's redundant.
Here, the experimental portion of the name is dropped.
We noticed some Swift clients rely on the serialized search paths in the module to
find dependencies and droping these paths altogether can lead to build failures like
rdar://85840921.
This change teaches the serialization to obfuscate the search paths and the deserialization
to recover them. This allows clients to keep accessing these paths without exposing
them when shipping the module to other users.
These modules are part of the experimental declarative string processing feature. If accepted to the Standard Library, _StringProcessing will be available via implicit import just like _Concurrency, though _MatchingEngine will still be hidden as an implementation detail.
`_MatchingEngine` will contain the general-purpose pattern matching engine ISA, bytecode, and executor. `_StringProcessing` will contain regular expression and pattern matching APIs whose implementation depends on the matching engine..
Also consolidates frontend flag `-enable-experimental-regex` as `-enable-experimental-string-processing`.
Resolves rdar://85478647.
The reason why I am doing this is that we are going to be enabling lexical
lifetimes early in the pipeline so that I can use it for the move operator's
diagnostics.
To make it easy for passes to know whether or not they should support lexical
lifetimes, I included a query on SILOptions called
supportsLexicalLifetimes. This will return true if the pass (given the passed in
option) should insert the lexical lifetime flag. This ensures that passes that
run in both pipelines (e.x.: AllocBoxToStack) know whether or not to set the
lexical lifetime flag without having to locally reason about it.
This is just chopping off layers of a larger patch I am upstreaming.
NOTE: This is technically NFC since it leaves the default alone of not inserting
lexical lifetimes at all.
Ideally, module interface verification should fail the build when fatal error occurs when
type checking emitted module interfaces. However, we found it's hard to stage this phase in
because the ideal case requires all Swift adopters to have valid interfaces. This new front-end flag allows
driver to downgrade all interface verification errors to warnings as an intermediate step.
These include _move and @_noImplicitCopy. I still need to wire up the parsing of
those behind this feature.
The reason that I am adding this now is that I am going to now need to make some
changes behind a feature flag and I have not yet needed to add one. The specific
reason I needed to add one here is to ensure that I properly guard inside _move
the call to Builtin.move so as to prevent a "cond_fail" incident.
P.S.: This work depends on experimental lexical lifetimes being enabled as well,
so I did that at the same time in this PR.
This additional supplement output should capture semantic info the compiler has
captured while building a Swift module. Similar to the source info file, the content of
the semantic info file should only be consumed by local tooling written in Swift.
Intro the frontend flag `-check-api-availability-only` that limits
availability checking to the API and SPI. This mode doesn't check the
availability of non-inlinable function bodies and of non-ABI-public decl
signatures.
This mode goal is to check all that is printed in the swiftinterface
file. It should be used in place of the wider
`-disable-availability-checking` when generating an interface for
platforms with no binaries.
rdar://81679692
A new LLVM IR affordance that allows expressing conditions under which globals
can be removed/dropped (even when marked with @llvm.used) is being discussed at:
- <https://reviews.llvm.org/D104496>
- <https://lists.llvm.org/pipermail/llvm-dev/2021-September/152656.html>
This is a preliminary implementation that marks runtime lookup records (namely
protocol records, type descriptors records and protocol conformance records)
with the !llvm.used.conditional descriptors. That allows link-time / LTO-time
removal of these records (by GlobalDCE) based on whether they're actually used
within the linkage unit. Effectively, this allows libraries that have a limited
and known set of clients, to be optimized against the client at LTO time, and
significantly reduce the code size of that library.
Parts of the implementation:
- New -conditional-runtime-records frontend flag to enable using !llvm.used.conditional
- IRGen code that emits these records can now emit these either as a single contiguous
array (asContiguousArray = true, the old way), which is used for JIT mode, or
as indivial globals (asContiguousArray = false), which is necessary for the
!llvm.used.conditional stripping to work.
- When records are emitted as individual globals, they have new names of
"\01l_protocol_" + mangled name of the protocol descriptor, and similarly for
other records.
- Fixed existing tests to account for individual records instead of a single array
- Added an IR level test, and an end-to-end execution test to demonstrate that
the !llvm.used.conditional-based stripping actually works.
Added ForceStructTypeLayouts. When enabled, IRGen will lower structs using the
aligned group of TypeLayout rather than using TypeInfos. This potentially leads
to a size increase as TypeInfos currently produce better code than the
TypeLayout route.
- Under -internalize-at-link, stop unconditionally marking all globals as used.
- Under -internalize-at-link, restrict visibility of vtables to linkage unit.
- Emit virtual method thunks for cross-module vcalls when VFE is enabled.
- Use thunks for vcalls across modules when VFE is enabled.
- Adjust TBDGen to account for virtual method thunks when VFE is enabled.
- Add an end-to-end test case for cross-module VFE.
- Witness method calls are done via @llvm.type.checked.load instrinsic call with a type identifier
- Type id of a witness method is the requirement's mangled name
- Witness tables get !type markers that list offsets and type ids of all methods in the wtable
- Added -enable-llvm-wme to enable Witness Method Elimination
- Added IR test and execution test
