...but don't hook it up to anything yet.
This is the very very start of the module stability / textual
interfaces feature described at
https://forums.swift.org/t/plan-for-module-stability/14551/
For now I've just made it a frontend option (not a driver option),
which is good enough for testing.
This flag is based on Clang's -fdebug-prefix-map, which lets the user remap absolute paths in debug info. This is necessary for reproducible builds and allows debugging to work on a different machine than the one that built the code when paths to the source may be different.
Sink the type checker request classes into the AST library, so that
various functions in the AST library can form type-checking requests.
The actual evaluator functions for these requests continue to live
in the Sema library, called via indirection through the function
pointer tables registered with the request-evaluator.
The bundling of the form of a request (e.g., the storage that makes up a request)
with the function that evaluates the request value requires us to perform
ad hoc indirection to address the AST —> Sema layering violation. For
example, ClassDecl::getSuperclass() calls through the LazyResolver (when
available) to form the appropriate request. This means that we cannot
use the the request-evaluator’s cache when LazyResolver is null, forcing
all cached state into the AST.
Provide the evaluator with a zone-based registration system, where each
request “zone” (e.g., the type checker’s requests) registers
callbacks to evaluate each kind of request within that zone. The
evaluator indirects through this table of function pointers, allowing
the request classes themselves to be available at a lower level (AST)
than the functions that perform the computation when the value isn’t
in the cache (e.g., Sema).
We are not taking advantage of the indirection yet; that’ll come in a
follow-up commit.
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.
Introduce another form of debugging dump for the evaluator, rendering the
complete dependency graph using GraphViz, including all dependencies and
values cached within the evaluator.
Introduce a CRTP base class, SimpleRequest, which simplifies the task of
defining a new request kind by handling the storage of the values (in a
std::tuple), their hashing, equality, printing, etc. The values are passed
along to the subclass’s operator() so they’re mostly treated as (const)
parameters, making mutation of the request state impossible.
Extend AnyValue and AnyRequest with printing logic, so we can print any
request for debugging purposes, and
Simplify the static registration of types for use with TypeID by introducing
a more declarative approach. Each zone provides a .def file listing the
types and templates defined by that zone. The .def file is processed by
include/swift/Basic/DefineTypeIDZone.h with its zone number, which assigns
values to each of the types/templates and introduces the TypeID
specializations.
Meant as a replacement for the barely-started iterative type checker,
introduce a simpler "evaluator" that can evaluate individual requests
(essentially, function objects with some additional API), caching
results as appropriate and detecting cycles.
When providing the -parseable-output flag to the swift compiler, it will provide json formatted messages about tasks that run.
I added some optional usage information in form of user time, system time and maxrss to the output. This can be used by other tools using the compiler to get some insights about time and memory usage.
Since the output does not longer match processes run (in batch mode), I also added a real_pid field so the client could reason about jobs that belong together if needed.
rdar://39798231
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.
Recent builds of clang give C++ globals of a type global constructors if they have a mix of explicitly initialized and default-initialized fields, apparently.
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.
StringLiteral is a subclass of StringRef that is intended to be used for global
constant strings in a constexpr context.
I am going to be refactoring some uses of const char foo[] = ""; to use this
instead.
When linking on Linux, we would fail with unresolved symbol references
to swift::FrontendStatsTracer::getTraceFormatter<T>. The use of the
types, which are defined in swiftSIL occur in swiftBasic. Provide
inline definitions of the constructors which cause the dependency on
some environments (e.g. Linux).
- Add const getItems().
- Fix const find().
- erase() returns a boolean.
- Set erase() should not perform two lookups.
The implementation is covered by the unit tests with a small addition.
Other trivial API changes are trivially tested in upcoming commits.
We have RelativeDirectPointer and RelativeIndirectablePointer. The latter
cannot be used with function pointers because it assumes the payload is
2-byte aligned and uses the least significant bit to dynamically
distinguish a direct pointer from an indirect pointer.
For resilient conformances, we want to use protocol dispatch thunks as
keys in the witness table template. They're not 2 byte aligned, and
they're always defined in a different image, so we need an unconditional
indirect relative pointer template.
