swift

bba00c6f - [AutoDiff] Diagnose unsupported coroutine differentiation. (#28921)

[AutoDiff] Diagnose unsupported coroutine differentiation. (#28921) Coroutines are functions that can yield values and suspend/resume execution. SIL has dedicated coroutine types. Coroutines are applied via `begin_apply`. `read` and `modify` accessors are coroutines. Coroutine differentiation requires extra support, so it should be diagnosed for now. Differentiation transform: - Generalize differentiation utilities from `ApplyInst` to `FullApplySite`. - `bool isArrayLiteralIntrinsic(FullApplySite)` - `void forEachApplyDirectResult(FullApplySite, llvm::function_ref<...>)` - `apply`: direct result is the `apply` result, unless the `apply` result has tuple-type and a single `destructure_tuple` user. Then, direct results are the `destructure_tuple` results. - `begin_apply`: direct results are the `begin_apply` results. - `try_apply`: direct results are successor blocks' arguments. - `bool LinearMapInfo::shouldDifferentiateApplySite(FullApplySite)` - Generalize activity analysis from `ApplyInst` to `FullApplySite`. - Propagate variedness for `FullApplySite` through direct/indirect results and `inout` arguments. - Propagate usefulness for `FullApplySite` through arguments. - Diagnose `begin_apply` instructions with active arguments and results in `PullbackEmitter::visitBeginApplyInst`. Sema: - Diagnose `@differentiable` attribute on `read` and `modify` coroutines. Resolves TF-1081. TF-1080 tracks coroutine differentiation support. TF-1083 tracks throwing function differentiation support.