llvm

e0e23551 - [SYCL][SYCLBIN] Implement kernel_bundle::ext_oneapi_get_content (#22061)

[SYCL][SYCLBIN] Implement kernel_bundle::ext_oneapi_get_content (#22061) Adds the runtime-side serializer for the `sycl_ext_oneapi_syclbin` extension. Users can now produce SYCLBIN bytes from any non-source kernel_bundle by calling `ext_oneapi_get_content()` (the inverse of the existing SYCLBIN load path). ### Implementation **Writer.** New SYCLBIN::SYCLBINDesc / AbstractModuleDesc / ImageDesc descriptor structs and SYCLBIN::write in the runtime SYCLBIN module. Mirrors the llvm/lib/Object/SYCLBIN.cpp writer but operates on in-memory image bytes rather than file paths, since kernel_bundles hold their device images in memory. Output is wrapped in an OffloadBinary v2 entry so it round-trips through the existing reader path. **Two-pass metadata composition**. `SYCLBIN::serializeImages` walks a bundle's live device images and emits one abstract module per image. For each image the property registry is built in two passes: 1. *Raw forward* : copy the static `RTDeviceBinaryImage` property sets verbatim (preserving producer order), minus the SYCLBIN-reserved sets. 2. *Runtime overlay*: a fixed OverrideTable of category-specific overrides patches in state that lives on the runtime `device_image_impl` rather than the static image: [SYCL/kernel names], [SYCL/kernel param opt], and user-set specialization-constant values. This addresses the original design flaw where the serializer ignored runtime overlays a `kernel_bundle_impl` carries on top of the static image. **Specialization constants.** SYCLBIN has no "user-set vs default" concept. A value set via `set_specialization_constant` before `ext_oneapi_get_content` is preserved through an optional [SYCL/specialization constants set values] property carrying the effective value blob (set descriptors hold their current value, unset descriptors their default). On reload the reader restores the per-descriptor `IsSet` state by comparing against the default-value blob. Backward compatible via presence-check (`isAvailable()`): compiler-produced SYCLBIN never carries it, old readers ignore it, new readers fall back when absent (no version bump in SYCLBIN). The descriptor set and default-value blob are left to the raw-forward pass so their producer ordering (which the flat value blob is indexed against) is never perturbed. **Bundle plumbing.** `kernel_bundle_impl::ext_oneapi_get_content` always re-serializes from the current `MUniqueDeviceImages`, so state-promoted bundles (compile/link/build) emit the post-promotion images. `ext_oneapi_source` bundles are rejected at compile time via `std::enable_if` (with a runtime assert backstop for internal callers). **Public API**: `kernel_bundle::ext_oneapi_get_content` for any non-source state, plumbed through `kernel_bundle_plain`. New ABI symbol registered in the Linux and Windows symbol dumps. Feature macro SYCL_EXT_ONEAPI_SYCLBIN. ## Tests * 19 unit tests across sycl/unittests/SYCL2020/SYCLBINSerialize{,JIT,Multi,Overrides,SpecConst}.cpp: compile_target round-trip, all three non-source bundle states, image payload round-trip, magic/version headers, IR vs native image classification, multi-image bundles (one abstract module per image), empty bundles, mixed IR+native, kernel-name and eliminated-arg-mask overlays, spec-constant descriptor/default/set-values round-trip including the two-constant set-then-reset ordering case, device-global property byte round-trip. * 6 E2E tests under sycl/test-e2e/SYCLBIN/get_content_*: baseline round-trip (compile → load → ext_oneapi_get_content → reload → run), multi-target variant (gated on opencl-aot + opencl-cpu-rt), arch round-trip, JIT→native, kernel-id round-trip, and specialization-constant round-trip.