Specifically, we write a string out like:
sil [isolation "$REPRESENTATION OF ISOLATION"] @function : $@convention(thin) ...
The idea is that by using a string, we avoid parsing issues of the isolation and
have flexibility. I left in the way we put isolation into the comment above
functions so I did not break any tests that rely on it. I also made it so that
we only accept this with sil tests that pass in the flag
"sil-print-function-isolation-info". I am going to for the next release put in a
full real implementation of this that allows for actor isolation to become a
true first class citizen in SIL. But for now this at least lets us write tests
in the short term.
Since this is temporary and behind a flag, I did not add support for
serialization since this is just for writing textual SIL tests.
Since LayoutPrespecialization has been enabled by default in all compiler
invocations for quite some time, it doesn't make sense for it to be treated as
experimental feature. Make it a baseline feature and remove all the
checks for it from the compiler.
We are going to need to add more flags to the various checked cast
instructions. Generalize the CastingIsolatedConformances bit in all of
these SIL instructions to an "options" struct that's easier to extend.
Precursor to rdar://152335805.
Implements SE-0460 -- the non-underscored version of @specialized.
It allows to specify "internal" (not abi affecting) specializations.
rdar://150033316
It derives the address of the first element of a vector, i.e. a `Builtin.FixedArray`, from the address of the vector itself.
Addresses of other vector elements can then be derived with `index_addr`.
Instead of passing in the substituted type, we pass in the
InFlightSubstitution. This allows the substituted type to be
recovered if needed, but we can now skip computing it for
the common case of LookUpConformanceInSubstitutionMap.
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.
When performing a dynamic cast to an existential type that satisfies
(Metatype)Sendable, it is unsafe to allow isolated conformances of any
kind to satisfy protocol requirements for the existential. Identify
these cases and mark the corresponding cast instructions with a new flag,
`[prohibit_isolated_conformances]` that will be used to indicate to the
runtime that isolated conformances need to be rejected.
I am doing this in preparation for adding the ability to represent in the SIL
type system that a function is global actor isolated. Since we have isolated
parameters in SIL, we do not need to represent parameter, nonisolated, or
nonisolated caller in the type system. So this should be sufficient for our
purposes.
I am adding this since I need to ensure that we mangle into thunks that convert
execution(caller) functions to `global actor` functions what the global actor
is. Otherwise, we cannot tell the difference in between such a thunk and a thunk
that converts execution(caller) to execution(concurrent).
The Protocol field isn't really necessary, because the conformance
stores the protocol. But we do need the substituted subject type
of the requirement, just temporarily, until an abstract conformance
stores its own subject type too.
Introduce a constructor that takes an `llvm::VersionTuple` directly, instead of
needing to spell out `VersionRange::allGTE(<tuple>)` which is unnecessarily
verbose.
This patch adds support for serialization of debug value instructions. Enablement is currently gated behind the -experimental-serialize-debug-info flag.
Previously, debug_value instructions were lost during serialization. This made it harder to debug cross module inlined functions.
The problem with `is_escaping_closure` was that it didn't consume its operand and therefore reference count checks were unreliable.
For example, copy-propagation could break it.
As this instruction was always used together with an immediately following `destroy_value` of the closure, it makes sense to combine both into a `destroy_not_escaped_closure`.
It
1. checks the reference count and returns true if it is 1
2. consumes and destroys the operand
This is used for synthetic uses like _ = x that do not act as a true use but
instead only suppress unused variable warnings. This patch just adds the
instruction.
Eventually, we can use it to move the unused variable warning from Sema to SIL
slimmming the type checker down a little bit... but for now I am using it so
that other diagnostic passes can have a SIL instruction (with SIL location) so
that we can emit diagnostics on code like _ = x. Today we just do not emit
anything at all for that case so a diagnostic SIL pass would not see any
instruction that it could emit a diagnostic upon. In the next patch of this
series, I am going to add SILGen support to do that.
Type annotations for instruction operands are omitted, e.g.
```
%3 = struct $S(%1, %2)
```
Operand types are redundant anyway and were only used for sanity checking in the SIL parser.
But: operand types _are_ printed if the definition of the operand value was not printed yet.
This happens:
* if the block with the definition appears after the block where the operand's instruction is located
* if a block or instruction is printed in isolation, e.g. in a debugger
The old behavior can be restored with `-Xllvm -sil-print-types`.
This option is added to many existing test files which check for operand types in their check-lines.
This API computes the re-borrow flags for guaranteed phis based on the presence of forwarding instructions in the incoming values.
This is not correct in all cases, because optimizations can optimize away forwarding instructions.
Fixes a verifier crash: rdar://139280579
This patch adds support for serialization and deserialization of
debug scopes.
Debug scopes are serialized in post order and enablement is
controlled through the experimental-serialize-debug-info flag which
is turned off by default. Functions only referred to by these debug
scopes are deserialized as zombie functions directly.
C++ swift::Parser is going to be replaced with SwiftParser+ASTGen.
Direct dependencies to it should be removed. Before that, remove
unnecessary '#include "swift/Parse/Parser.h"' to clarify what actually
depends on 'swift::Parser'.
Split 'swift::parseDeclName()' et al. into the dedicated files.
I am adding this instruction to express artificially that two non-Sendable
values should be part of the same region. It is meant to be used in cases where
due to unsafe code using Sendable, we stop propagating a non-Sendable dependency
that needs to be made in the same region of a use of said Sendable value. I
included an example in ./docs/SIL.rst of where this comes up with @out results
of continuations.
For now this will only be used for HopToMainActorIfNeeded thunks. I am creating
this now since in the past there has only been one option for creating
thunks... to create the thunk in SILGen using SILGenThunk. This code is hard to
test and there is a lot of it. By using an instruction here we get a few benefits:
1. We decouple SILGen from needing to generate new kinds of thunks. This means
that SILGenThunk does not need to expand to handle more thunks.
2. All thunks implemented via ThunkInst will be easy to test in a decoupled way
with SIL tests.
3. Even though this stabilizes the patient, we still have many thunks in SILGen
and various parts of the compiler. Over time, we can swap to this model,
allowing us to hopefully eventually delete SILGenThunk.
