Add RayTracing pipeline kind, shader stages, and YAML schema#1270
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…rce allocation Introduce the foundational types for ray tracing acceleration structures: abstract `AccelerationStructure` base class, geometry/instance descriptors, BLAS/TLAS build-request structs with size queries, the `AccelerationStructureBuildFlags` bitmask (using `LLVM_DECLARE_ENUM_AS_BITMASK` since `TextureUsage` already uses the intrusive `LLVM_MARK_AS_BITMASK_ENUM`; `TextureUsage` also gains its previously-missing `LLVM_ENABLE_BITMASK_ENUMS_IN_NAMESPACE()`), and AS resource allocation across DX12, Vulkan, and Metal. Recording build commands lands in a follow-up commit on top of the ComputeEncoder abstraction. Vulkan device creation switches to a single `vkGetPhysicalDeviceFeatures2` call covering every extension feature struct we care about (atomic-int64, mesh-shader, acceleration-structure, BDA on 1.1): each struct is chained into `pNext` before the query, and post-query we verify the gating bool and clear the sub-features we don't enable (capture-replay, indirect-build, multiview, etc.). Drive-by: rather than letting `vkCreateDevice` reject the device with a generic `VK_ERROR_FEATURE_NOT_PRESENT`, the code now returns a descriptive `llvm::Error` naming the extension and the bool that came back zero — pinpointing the case where a driver advertises an extension but reports its base feature as `VK_FALSE`. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com> Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
…lper
Move acceleration-structure build commands behind the abstract
ComputeEncoder interface so the orchestration (data upload, build-request
creation, AS allocation, build recording) can live in one place rather
than splitting across three backends.
ComputeEncoder gains a single batchBuildAS(ArrayRef<ASBuildItem>) method.
Each item carries an AccelerationStructure plus a BLAS or TLAS build
request via PointerUnion. The caller guarantees no inter-item memory
dependencies inside a batch — backends record the whole batch with one
barrier slot, no per-element barriers.
- Vulkan: single vkCmdBuildAccelerationStructuresKHR call covering the
whole batch. TLAS items serialize VkAccelerationStructureInstanceKHR
into a device-address upload buffer, BLAS items pull addresses from
each VulkanBuffer (new getDeviceAddress accessor). Storage buffers
transparently gain SHADER_DEVICE_ADDRESS + ACCEL_BUILD_INPUT_READ_ONLY
flags when ray tracing is supported, with the matching
VkMemoryAllocateFlagsInfo chained on every allocation.
- DX12: loop calling BuildRaytracingAccelerationStructure per item with
no intermediate barriers; D3D12_RAYTRACING_INSTANCE_DESC is
bit-identical to the Vulkan instance struct.
- Metal: lazy transition to MTL::AccelerationStructureCommandEncoder,
deduplicates BLAS handles into the
MTL::InstanceAccelerationStructureDescriptor's instancedAccelera-
tionStructures array (Metal references BLASes by index, not GPU
address).
Each backend's CommandBuffer now carries a back-pointer to its owning
Device so the encoder can reach device-loaded entry points and helpers,
plus a keep-alive list for AS scratch and instance buffers.
A shared helper buildPipelineAccelerationStructures in lib/API/Device.cpp
walks Pipeline::AccelStructs, uploads vertex/index data via the new
createBufferWithData, builds requests, allocates AS objects, and issues
two batchBuildAS calls (BLAS batch then TLAS batch — VUID-03403 forbids
referencing a sibling dstAccelerationStructure in one command). Each
backend's executeProgram calls this helper to build the pipeline's AS
objects.
Descriptor binding for AS resources is intentionally still missing — the
tests progress past AS-build now and surface only the descriptor-write
gap.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Wire up acceleration-structure descriptor binding end-to-end across all three backends so shaders can actually consume the TLAS that buildPipelineAccelerationStructures produced — completing the stack and promoting the three InlineRT tests from XFAIL to passing. Vulkan: createDescriptorPool counts AS descriptors in a separate scalar (the KHR enum value 1000150000 doesn't fit in the indexed array used for the core types) and emits one VkDescriptorPoolSize for them. createDescriptorSets resolves each AS resource via Resource::TLASPtr, locates the matching VulkanAccelerationStructure in InvocationState::AccelStructs (BLASes-then-TLASes layout, matching the helper's documented declaration order), and writes the handle through a VkWriteDescriptorSetAccelerationStructureKHR chained on the descriptor write's pNext. The dispatch's pre-barrier dst access now includes VK_ACCESS_ACCELERATION_STRUCTURE_READ_BIT_KHR so the prior AS-build's writes are made visible to the shader's RayQuery reads. Device creation also enables VK_KHR_ray_query when supported so the RayQuery shader instructions actually function. DX12: writes a D3D12_SRV_DIMENSION_RAYTRACING_ACCELERATION_STRUCTURE SRV with the AS GPU virtual address as Location into the heap slot that createBuffers reserved (CreateShaderResourceView with a null resource — the AS data lives in the buffer pointed to by Location). Metal: the Metal shader converter doesn't bind the AS directly; the shader reads a buffer containing an IRRaytracingAccelerationStructure- GPUHeader that holds the AS's gpuResourceID plus a pointer to an instance-contributions array. createBuffers allocates and fills both buffers per AS-descriptor entry, then points the descriptor at the header buffer's GPU address. The TLAS itself is built with the UserID instance-descriptor variant so HLSL CommittedInstanceID() returns the YAML-specified per-instance ID instead of the array index. The three InlineRT tests now actually exercise the AS end-to-end: TraceRayInline issues a RayQuery against `Scene` and writes a hit-dependent value into `Output` (the instance ID for multi-instance, 1/0 otherwise). The catch-all `XFAIL: *` is dropped; `XFAIL: Clang` remains. The test shaders gain explicit `[[vk::binding]]` annotations since their `t0`/`u0` registers would otherwise collide under the default dxc HLSL→SPIR-V mapping. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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First per-backend bring-up in the PSO raytracing series (llvm#1268). Adds the API surface (ComputeEncoder::dispatchRays, Device::createPipelineRT, Device::createShaderBindingTable, RayTracingPipelineCreateDesc) plus the Vulkan implementation behind it. D3D12 and Metal stub the new methods with not-yet-supported errors; their bring-up lands in follow-up PRs. The pre-existing YAML schema struct from PR llvm#1270 is renamed ShaderBindingTable -> ShaderBindingTableDesc so the bare name is free for the runtime resource class (parallel to BLASDesc / TLASDesc vs AccelerationStructure). A new include/API/ShaderBindingTable.h holds the abstract runtime base; concrete backend SBT classes derive from it with LLVM-style classof / cast<>. The VulkanDevice's prior `RaytracingFunctions RT` lumped AS and RT pipeline entry points together. They split into two structs — `ASFunctions AS` and `RTPipelineFunctions RT` — matching the actual feature-gate split (AS+ray-query is a complete configuration on its own, RT pipeline is layered on top). `HasRayTracingSupport` renames to `HasASSupport`, and a separate `HasRTPipelineSupport` tracks the new VK_KHR_ray_tracing_pipeline extension. Vulkan bring-up: - Extension: VK_KHR_ray_tracing_pipeline is requested when reported, with VkPhysicalDeviceRayTracingPipelineFeaturesKHR chained into the pre-create feature query. After the query the gating rayTracingPipeline bool is checked; capture-replay / trace-rays- indirect / traversal-primitive-culling sub-features are cleared since the tests don't exercise them. - Function pointers: vkCreateRayTracingPipelinesKHR, vkGetRayTracingShaderGroupHandlesKHR, vkCmdTraceRaysKHR. - Properties: VkPhysicalDeviceRayTracingPipelinePropertiesKHR is cached at device-create time for SBT handle size / alignment / base-alignment. - VKRayTracingPipelineState derives from VulkanPipelineState; an IsRayTracing flag on the base lets the existing Vulkan cast<> path stay polymorphic without adding a new GPUAPI value. classof tests both the API and the flag. The derived class also carries a StringMap<uint32_t> resolving each shader EntryPoint or HitGroup Name to its index in the pipeline's group array, plus per-bucket counts so the SBT builder can slice the contiguous handle blob into raygen / miss / hit / callable regions. - createPipelineRT builds a single VkShaderModule (the DXIL library compiles to one SPIR-V module with multiple OpEntryPoints), then one VkPipelineShaderStageCreateInfo per Shader entry and one VkRayTracingShaderGroupCreateInfoKHR per general shader / hit group. Pipeline layout is shared with the compute path via createPipelineLayout, gated on all six RT stage flags so any binding can be consumed from any RT shader. - createShaderBindingTable allocates a host-visible coherent buffer big enough for four regions and lays out each entry as [handle bytes][localRootData bytes][padding-to-stride]. Per-region stride = align(handleSize + max-local-root-data-in-region, handleAlignment); per-region size = align(count * stride, baseAlignment). LocalRootData support comes free from the PR1 SBT schema; the test doesn't exercise it yet. Each region's VkStridedDeviceAddressRegionKHR derives from the buffer's vkGetBufferDeviceAddress. - dispatchRays binds the pipeline at VK_PIPELINE_BIND_POINT_RAY_TRACING_KHR, emits a pre-barrier with AS_READ + SHADER_READ/WRITE dst access into RAY_TRACING_SHADER_BIT_KHR, then calls vkCmdTraceRaysKHR with the SBT's four region structs. - createCommands picks the new bind point for RT pipelines so vkCmdBindDescriptorSets binds to the right point. executeProgram's isRayTracing branch builds a RayTracingPipelineCreateDesc from the YAML, calls createPipelineRT then createShaderBindingTable, and keeps both on InvocationState for the dispatch. raygen-roundtrip.test now expects DirectX/Metal/Clang to XFAIL; on a DXC + Vulkan combo with VK_KHR_ray_tracing_pipeline supported the test should PASS via this implementation. On the user's Linux + clang-dxc loop the test still XFAILs because clang-dxc doesn't yet lower [shader("raygeneration")] entry points to SPIR-V, so the Clang XFAIL token catches the compile failure. CI on a working DXC install will exercise the runtime path. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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First per-backend bring-up in the PSO raytracing series (llvm#1268). Adds the API surface (ComputeEncoder::dispatchRays, Device::createPipelineRT, Device::createShaderBindingTable, RayTracingPipelineCreateDesc) plus the Vulkan implementation behind it. D3D12 and Metal stub the new methods with not-yet-supported errors; their bring-up lands in follow-up PRs. The pre-existing YAML schema struct from PR llvm#1270 is renamed ShaderBindingTable -> ShaderBindingTableDesc so the bare name is free for the runtime resource class (parallel to BLASDesc / TLASDesc vs AccelerationStructure). A new include/API/ShaderBindingTable.h holds the abstract runtime base; concrete backend SBT classes derive from it with LLVM-style classof / cast<>. The VulkanDevice's prior `RaytracingFunctions RT` lumped AS and RT pipeline entry points together. They split into two structs — `ASFunctions AS` and `RTPipelineFunctions RT` — matching the actual feature-gate split (AS+ray-query is a complete configuration on its own, RT pipeline is layered on top). `HasRayTracingSupport` renames to `HasASSupport`, and a separate `HasRTPipelineSupport` tracks the new VK_KHR_ray_tracing_pipeline extension. Vulkan bring-up: - Extension: VK_KHR_ray_tracing_pipeline is requested when reported, with VkPhysicalDeviceRayTracingPipelineFeaturesKHR chained into the pre-create feature query. After the query the gating rayTracingPipeline bool is checked; capture-replay / trace-rays- indirect / traversal-primitive-culling sub-features are cleared since the tests don't exercise them. - Function pointers: vkCreateRayTracingPipelinesKHR, vkGetRayTracingShaderGroupHandlesKHR, vkCmdTraceRaysKHR. - Properties: VkPhysicalDeviceRayTracingPipelinePropertiesKHR is cached at device-create time for SBT handle size / alignment / base-alignment. - VKRayTracingPipelineState derives from VulkanPipelineState; an IsRayTracing flag on the base lets the existing Vulkan cast<> path stay polymorphic without adding a new GPUAPI value. classof tests both the API and the flag. The derived class also carries a StringMap<uint32_t> resolving each shader EntryPoint or HitGroup Name to its index in the pipeline's group array, plus per-bucket counts so the SBT builder can slice the contiguous handle blob into raygen / miss / hit / callable regions. - createPipelineRT builds a single VkShaderModule (the DXIL library compiles to one SPIR-V module with multiple OpEntryPoints), then one VkPipelineShaderStageCreateInfo per Shader entry and one VkRayTracingShaderGroupCreateInfoKHR per general shader / hit group. Pipeline layout is shared with the compute path via createPipelineLayout, gated on all six RT stage flags so any binding can be consumed from any RT shader. - createShaderBindingTable allocates a host-visible coherent buffer big enough for four regions and lays out each entry as [handle bytes][localRootData bytes][padding-to-stride]. Per-region stride = align(handleSize + max-local-root-data-in-region, handleAlignment); per-region size = align(count * stride, baseAlignment). LocalRootData support comes free from the PR1 SBT schema; the test doesn't exercise it yet. Each region's VkStridedDeviceAddressRegionKHR derives from the buffer's vkGetBufferDeviceAddress. - dispatchRays binds the pipeline at VK_PIPELINE_BIND_POINT_RAY_TRACING_KHR, emits a pre-barrier with AS_READ + SHADER_READ/WRITE dst access into RAY_TRACING_SHADER_BIT_KHR, then calls vkCmdTraceRaysKHR with the SBT's four region structs. - createCommands picks the new bind point for RT pipelines so vkCmdBindDescriptorSets binds to the right point. executeProgram's isRayTracing branch builds a RayTracingPipelineCreateDesc from the YAML, calls createPipelineRT then createShaderBindingTable, and keeps both on InvocationState for the dispatch. raygen-roundtrip.test now expects DirectX/Metal/Clang to XFAIL; on a DXC + Vulkan combo with VK_KHR_ray_tracing_pipeline supported the test should PASS via this implementation. On the user's Linux + clang-dxc loop the test still XFAILs because clang-dxc doesn't yet lower [shader("raygeneration")] entry points to SPIR-V, so the Clang XFAIL token catches the compile failure. CI on a working DXC install will exercise the runtime path. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Foundational bring-up for PSO-based raytracing tracked in llvm#1268. Lays out the framework-side surface (stage enums, pipeline kind, YAML schema, lit infrastructure) so subsequent per-backend bring-up PRs (VK → DX12 → Metal) only have to fill in pipeline-state-object creation, SBT construction, and DispatchRays. No backend can run an RT pipeline yet — each one's executeProgram gains a terminal `else if (P.isRayTracing())` that returns a "not yet supported" error. Pipeline.h gets six new Stages (RayGeneration, Miss, ClosestHit, AnyHit, Intersection, Callable), `ShaderPipelineKind::RayTracing`, an `isRayTracingStage` predicate, and `Pipeline::isRayTracing()`. The declarative YAML schema for an RT pipeline lives alongside the existing AccelerationStructureDescs: a `HitGroup` (Triangles | Procedural, with ClosestHit + optional AnyHit / Intersection entries), a `RayTracingPipelineConfig` block (MaxTraceRecursionDepth, MaxPayloadSizeInBytes, MaxAttributeSizeInBytes, optional PipelineFlags), and a `ShaderBindingTable` block with raygen / miss / hit-group / callable record arrays. SBTEntry carries an optional `LocalRootData` byte array reserved for the upcoming local-root-signature work. validatePipelineKind grows an RT branch: it allows multiple shaders of the same RT stage (a pipeline can have several misses or hit groups — the existing duplicate check would have rejected them), requires at least one RayGeneration, and rejects mixing RT with Compute/Vertex/Mesh. The reverse check rejects HitGroups / RTConfig / SBT on any non-RT pipeline. validateDispatchParameters reinterprets DispatchGroupCount as {Width, Height, Depth} for the eventual DispatchRays and forbids VertexCount on RT. Existing Stages switches grow the six new cases: * VK: getShaderStageFlag maps each RT stage to its VK_SHADER_STAGE_*_KHR bit so PR 2 can build VkPipelineShaderStageCreateInfos for the RT pipeline. * Metal: getShaderStage unreachables on RT (the metal-irconverter RT path takes a different route from the IRShaderStage one). * TraditionalRasterPipelineCreateDesc::setShader adds the RT stages to its existing "not a raster stage" unreachable group. test/lit.cfg.py adds a `%dxc_target_lib` substitution (same compiler, distinct name to signal `-T lib_6_x` library targets at a glance) and a `raytracing-pipeline` available-feature. On DX it tracks RaytracingTier >= 1.0; on Vulkan it aliases off the VK_KHR_ray_tracing_pipeline extension already reported by the device. The extension isn't enabled on the VkDevice yet — that lands in PR 2 — but the lit-level capability detection is independent of what the backend currently consumes, so a developer on a VK box can already see the foundational test routed through the RT path. The foundational test `Feature/RT/raygen-roundtrip.test` exercises the full RT YAML schema in one shape: raygen + miss + closest-hit shaders, a BLAS/TLAS pair, a HitGroups list, RayTracingPipelineConfig, and a ShaderBindingTable. `# REQUIRES: raytracing-pipeline` and `# XFAIL: *` keep it expectedly failing until the per-backend PRs drop entries from the XFAIL list as each one starts dispatching real rays. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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First per-backend bring-up in the PSO raytracing series (llvm#1268). Adds the API surface (ComputeEncoder::dispatchRays, Device::createPipelineRT, Device::createShaderBindingTable, RayTracingPipelineCreateDesc) plus the Vulkan implementation behind it. D3D12 and Metal stub the new methods with not-yet-supported errors; their bring-up lands in follow-up PRs. The pre-existing YAML schema struct from PR llvm#1270 is renamed ShaderBindingTable -> ShaderBindingTableDesc so the bare name is free for the runtime resource class (parallel to BLASDesc / TLASDesc vs AccelerationStructure). A new include/API/ShaderBindingTable.h holds the abstract runtime base; concrete backend SBT classes derive from it with LLVM-style classof / cast<>. The VulkanDevice's prior `RaytracingFunctions RT` lumped AS and RT pipeline entry points together. They split into two structs — `ASFunctions AS` and `RTPipelineFunctions RT` — matching the actual feature-gate split (AS+ray-query is a complete configuration on its own, RT pipeline is layered on top). `HasRayTracingSupport` renames to `HasASSupport`, and a separate `HasRTPipelineSupport` tracks the new VK_KHR_ray_tracing_pipeline extension. Vulkan bring-up: - Extension: VK_KHR_ray_tracing_pipeline is requested when reported, with VkPhysicalDeviceRayTracingPipelineFeaturesKHR chained into the pre-create feature query. After the query the gating rayTracingPipeline bool is checked; capture-replay / trace-rays- indirect / traversal-primitive-culling sub-features are cleared since the tests don't exercise them. - Function pointers: vkCreateRayTracingPipelinesKHR, vkGetRayTracingShaderGroupHandlesKHR, vkCmdTraceRaysKHR. - Properties: VkPhysicalDeviceRayTracingPipelinePropertiesKHR is cached at device-create time for SBT handle size / alignment / base-alignment. - VKRayTracingPipelineState derives from VulkanPipelineState; an IsRayTracing flag on the base lets the existing Vulkan cast<> path stay polymorphic without adding a new GPUAPI value. classof tests both the API and the flag. The derived class also carries a StringMap<uint32_t> resolving each shader EntryPoint or HitGroup Name to its index in the pipeline's group array, plus per-bucket counts so the SBT builder can slice the contiguous handle blob into raygen / miss / hit / callable regions. - createPipelineRT builds a single VkShaderModule (the DXIL library compiles to one SPIR-V module with multiple OpEntryPoints), then one VkPipelineShaderStageCreateInfo per Shader entry and one VkRayTracingShaderGroupCreateInfoKHR per general shader / hit group. Pipeline layout is shared with the compute path via createPipelineLayout, gated on all six RT stage flags so any binding can be consumed from any RT shader. - createShaderBindingTable allocates a host-visible coherent buffer big enough for four regions and lays out each entry as [handle bytes][localRootData bytes][padding-to-stride]. Per-region stride = align(handleSize + max-local-root-data-in-region, handleAlignment); per-region size = align(count * stride, baseAlignment). LocalRootData support comes free from the PR1 SBT schema; the test doesn't exercise it yet. Each region's VkStridedDeviceAddressRegionKHR derives from the buffer's vkGetBufferDeviceAddress. - dispatchRays binds the pipeline at VK_PIPELINE_BIND_POINT_RAY_TRACING_KHR, emits a pre-barrier with AS_READ + SHADER_READ/WRITE dst access into RAY_TRACING_SHADER_BIT_KHR, then calls vkCmdTraceRaysKHR with the SBT's four region structs. - createCommands picks the new bind point for RT pipelines so vkCmdBindDescriptorSets binds to the right point. executeProgram's isRayTracing branch builds a RayTracingPipelineCreateDesc from the YAML, calls createPipelineRT then createShaderBindingTable, and keeps both on InvocationState for the dispatch. raygen-roundtrip.test now expects DirectX/Metal/Clang to XFAIL; on a DXC + Vulkan combo with VK_KHR_ray_tracing_pipeline supported the test should PASS via this implementation. On the user's Linux + clang-dxc loop the test still XFAILs because clang-dxc doesn't yet lower [shader("raygeneration")] entry points to SPIR-V, so the Clang XFAIL token catches the compile failure. CI on a working DXC install will exercise the runtime path. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Depends on #1245
Summary
Foundational PR in the PSO-based raytracing bring-up series tracked in #1268. Stacks on top of #1245 (which depends on #1244, which depends on #1232) — only the top commit on this branch is new; the rest are the inline-RT bring-up already in review.
Lays out the framework-side surface needed by the upcoming backend PRs:
ShaderPipelineKind::RayTracingplus six newStages—RayGeneration,Miss,ClosestHit,AnyHit,Intersection,Callable— withisRayTracingStage/Pipeline::isRayTracing()helpers.HitGroup(Triangles | Procedural, ClosestHit + optional AnyHit / Intersection),RayTracingPipelineConfig(MaxTraceRecursionDepth, MaxPayloadSizeInBytes, MaxAttributeSizeInBytes, optional PipelineFlags), andShaderBindingTable(raygen / miss / hit-group / callable records, each with optional reserved LocalRootData bytes).validatePipelineKindallows duplicate RT stages (a pipeline can have several miss / hit-group shaders, which the existing duplicate check would have rejected), requires at least one RayGeneration, and rejects mixing with Compute/Vertex/Mesh. The reverse check rejects HitGroups / RTConfig / SBT on any non-RT pipeline.validateDispatchParametersreinterpretsDispatchGroupCountas{Width, Height, Depth}for the upcoming DispatchRays and forbids VertexCount on RT.Stagesswitches across the backends grow the six RT cases — Vulkan maps each one to itsVK_SHADER_STAGE_*_KHRbit ready for PR 2; Metal unreachables on RT (metal_irconvertertakes a different route); raster pipelinesetShaderadds them to the existing unreachable group.executeProgramgets a terminalelse if (P.isRayTracing())that returns a "not yet supported on " error so PR2/3/4 just have to replace it.%dxc_target_liblit substitution (same compiler binary, separate name for-T lib_6_xlibrary targets);raytracing-pipelineavailable-feature gated on DXRaytracingTier >= 1.0and the VulkanVK_KHR_ray_tracing_pipelineextension being reported by the device.test/Feature/RT/raygen-roundtrip.testexercising the full schema (raygen+miss+CH, BLAS/TLAS, HitGroups, RTConfig, SBT). Gated onraytracing-pipelineandXFAIL: *until each backend bring-up lands.Test plan
Feature/RT/raygen-roundtrip.testdiscovered and XFAILs onclang-vk(the local Linux+Clang setup); XFAIL count goes 143 → 144.-T lib_6_5DXC the XFAIL should be satisfied by the per-backend "RayTracing pipeline not yet supported" stub rather than the local Clang HLSL→SPIRV missing[shader("raygeneration")]lowering. Worth verifying in CI.