Whenever we have a reference to a foreign function/variable in SIL, use
a mangled name at the SIL level with the C name in the asmname
attribute. The expands the use of asmname to three kinds of cases that
it hadn't been used in yet:
* Declarations imported from C headers/modules
* @_cdecl @implementation of C headers/modules
* @_cdecl functions in general
Some code within the SIL pipeline makes assumptions that the C names of
various runtime functions are reflected at the SIL level. For example,
the linking of Embedded Swift runtime functions is done by-name, and
some of those names refer to C functions (like `swift_retain`) and
others refer to Swift functions that use `@_silgen_name` (like
`swift_getDefaultExecutor`). Extend the serialized module format to
include a table that maps from the asmname of functions/variables over
to their mangled names, so we can look up functions by asmname if we
want. These tables could also be used for checking for declarations
that conflict on their asmname in the future. Right now, we leave it
up to LLVM or the linker to do the checking.
`@_silgen_name` is not affected by these changes, nor should it be:
that hidden feature is specifically meant to affect the name at the
SIL level.
The vast majority of test changes are SIL tests where we had expected
to see the C/C++/Objective-C names in the tests for references to
foreign entities, and now we see Swift mangled names (ending in To).
The SIL declarations themselves will have a corresponding asmname.
Notably, the IRGen tests have *not* changed, because we generally the
same IR as before. It's only the modeling at the SIL lever that has
changed.
Another part of rdar://137014448.
1. When differentiable nested function (closure) is specialized by capture promotion pass ensure we generate a differentiability witness for the specialized function as well. Ensure the original witness is removed if the original function becomes dead.
2. Differentiability witnesses for a function could originate either from its `@differentiable` attribute or from explicit `@derivative(of:)` attribute on the derivative. In the latter case the derivative itself might not be emitted, while original function is (e.g. original function is `@inlineable`, but derivative is `@usableFromInline`). Previously both cases were handled only when function body was emitted. As a result we missed witness in the aforementioned case. Ensure the
differentiability witness originating from `@derivative(of:)` is emitted even if we're not going to emit body of the derivative.
Fixes#59135
Convert a bunch of places where we're dumping to stderr and calling
`abort` over to using `ABORT` such that the message gets printed to
the pretty stack trace. This ensures it gets picked up by
CrashReporter.
Store specialize witness tables in a separate lookup table in the module. This allows that for a normal conformance there can exist the original _and_ a specialized witness table.
Also, add a boolean property `isSpecialized` to `WitnessTable` which indicates whether the witness table is specialized or not.
We currently load it for prespecialization when it wasn't loaded initially.
This causes an inadvertant issue for invertible protocols.
When we don’t have the stdlib loaded initially, we “synthesize” the
invertible protocol from the Builtin module by creating a new `ProtocolDecl*`
and stashing it on the `ASTContext`.
If the stdlib gets loaded later, deserialized stdlib types conform to the deserialized `Escapable` protocol
which has a different `ProtocolDecl *` pointer for `Escapable`.
So queries like `conformsToInvertible` fail because they are using the wrong `ProtocolDecl*`
for `Copyable`/`Escapable` while looking up the ConformanceTable.
In Embedded Swift, witness method lookup is done from specialized witness tables.
For this to work, the type of witness_method must be specialized as well.
Otherwise the method call would be done with wrong parameter conventions (indirect instead of direct).
The main change here is to associate a witness table with a `ProtocolConformance` instead of a `RootProtocolConformance`.
A `ProtocolConformance` is the base class and can be a `RootProtocolConformance` or a `SpecializedProtocolConformance`.
Although I don't plan to bring over new assertions wholesale
into the current qualification branch, it's entirely possible
that various minor changes in main will use the new assertions;
having this basic support in the release branch will simplify that.
(This is why I'm adding the includes as a separate pass from
rewriting the individual assertions)
[serialized_for_package] if Package CMO is enabled. The latter kind
allows a function to be serialized even if it contains loadable types,
if Package CMO is enabled. Renamed IsSerialized_t as SerializedKind_t.
The tri-state serialization kind requires validating inlinability
depending on the serialization kinds of callee vs caller; e.g. if the
callee is [serialized_for_package], the caller must be _not_ [serialized].
Renamed `hasValidLinkageForFragileInline` as `canBeInlinedIntoCaller`
that takes in its caller's SerializedKind as an argument. Another argument
`assumeFragileCaller` is also added to ensure that the calle sites of
this function know the caller is serialized unless it's called for SIL
inlining optimization passes.
The [serialized_for_package] attribute is allowed for SIL function, global var,
v-table, and witness-table.
Resolves rdar://128406520
We maintained a counter of the number of pending local archetypes
that had not yet been defined. However, if an instruction that
references a pending local archetype was deleted before the
local archetype was defined, the counter would never decrement.
Before reading the counter value, garbage collect any inserted
placeholders that have no uses. These correspond to pending
local archetypes that are no longer in use and will never be
defined.
LLVM is presumably moving towards `std::string_view` -
`StringRef::startswith` is deprecated on tip. `SmallString::startswith`
was just renamed there (maybe with some small deprecation inbetween, but
if so, we've missed it).
The `SmallString::startswith` references were moved to
`.str().starts_with()`, rather than adding the `starts_with` on
`stable/20230725` as we only had a few of them. Open to switching that
over if anyone feels strongly though.
It's not thread safe and can cause false alarms in case multiple modules exist in different threads. E.g. when building swiftmodules from interfaces.
The leaking check is not important anymore because the builder APIs enforce that instructions are not leaking.
I.e. it's not possible to create an instruction without inserting it into a basic block. Also, it's not possible to remove an instruction from a block without deleting it.
rdar://122169263
Ad-hoc requirements are now obsolete by making `remoteCall`,
`record{Argument, ReturnType}`, `decodeNextArgument` protocols
requirements and injecting witness tables for `SerializationRequirement`
conformances during IRGen.
Decls with a package access level are currently set to public SIL
linkages. This limits the ability to have more fine-grained control
and optimize around resilience and serialization.
This PR introduces a separate SIL linkage and FormalLinkage for
package decls, pipes them down to IRGen, and updates linkage checks
at call sites to include package linkage.
Resolves rdar://121409846
First, "can have an absence of Copyable" is a rather confusing notion,
so the query is flipped to "can be Copyable". Next, it's more robust to
ask if a conformance exists for the TypeDecl to answer that question,
rather than trying to replicate what happens within that conformance
lookup.
Also renames `TypeDecl::isEscapable` to match.
I've renamed the method to `TypeDecl::isNoncopyable`, because the query
doesn't make sense for many other kinds of `ValueDecl`'s beyond the
`TypeDecl`'s. In fact, it looks like no one was relying on that anyway.
Thus, we now have a distinction where in Sema, you ask whether
a `Type` or `TypeDecl` is "Noncopyable". But within SIL, we still
preserve the notion of "move-only" since there is additionally the
move-only type wrapper for types that otherwise support copying.
Deserialization is calling AccessMarkerElimination repeatedly on the
same function.
The bug was introduced here:
commit 872bf40e17
Date: Mon Aug 13 10:24:20 2018
[sil-optimizer] Centralize how we send out serialization notifications.
Where the code that uniques the deserialization callbacks was simply
removed!
As a result, this pass was being invoked a number of times equal to
the number of functions in the module *multiplied* by the number of
functions being deserialized.
Fixes rdar://117141871 (Building spends most of its time in
AccessMarkerElimination)
