Consider an `@_alwaysEmitIntoClient` function and a custom derivative
defined
for it. Previously, such a combination resulted different errors under
different
circumstances.
Sometimes, there were linker errors due to missing derivative function
symbol -
these occurred when we tried to find the derivative in a module, while
it
should have been emitted into client's code (and it did not happen).
Sometimes, there were SIL verification failures like this:
```
SIL verification failed: internal/private function cannot be serialized or serializable: !F->isAnySerialized() || embedded
```
Linkage and serialization options for the derivative were not handled
properly,
and, instead of PublicNonABI linkage, we had Private one which is
unsupported
for serialization - but we need to serialize `@_alwaysEmitIntoClient`
functions
so the client's code is able to see them.
This patch resolves the issue and adds proper handling of custom
derivatives
of `@_alwaysEmitIntoClient` functions. Note that either both the
function and
its custom derivative or none of them should have
`@_alwaysEmitIntoClient`
attribute, mismatch in this attribute is not supported.
The following cases are handled (assume that in each case client's code
uses
the derivative).
1. Both the function and its derivative are defined in a single file in
one module.
2. Both the function and its derivative are defined in different files
which
are compiled to a single module.
3. The function is defined in one module, its derivative is defined in
another
module.
4. The function and the derivative are defined as members of a protocol
extension in two separate modules - one for the function and one for the
derivative. A struct conforming the protocol is defined in the third
module.
5. The function and the derivative are defined as members of a struct
extension in two separate modules - one for the function and one for the
derivative.
The changes allow to define derivatives for methods of `SIMD`.
Fixes#54445
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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 reverts commit aa5dddb952.
Fixes `preset=buildbot,tools=RA,stdlib=DA` CI job, which without this revert fails on `AutoDiff/SILGen/nil_coalescing.swift` test.
