Making it easier to work with shaders https://git.yummers.dev/slang.git/atom?h=master 2025-08-07T21:43:25+00:00 2025-08-07T21:43:25+00:00 Harsh Aggarwal (NVIDIA) haaggarwal@nvidia.com 2025-08-07T21:43:25+00:00 urn:sha1:e595743b5aa4f6bd88800cfbcfd6eead3cc3d01b Due to an older version of spec referred there was an inconsitency v1.29 2/20/2025 - [HitObject LoadLocalRootArgumentsConstant] Latest spec https://microsoft.github.io/DirectX-Specs/d3d/Raytracing.html#hitobject-loadlocalroottableconstant Refer: OptiX backend support for Shader Execution Reordering (SER) features as outlined in issue #6647. - 2025-05-26T18:22:45+00:00 Harsh Aggarwal (NVIDIA) haaggarwal@nvidia.com 2025-05-26T18:22:45+00:00 urn:sha1:5280ca81025d42239fec492eb72d38606308751a * Fix operator precedence in OptiX ray payload pointer casting Added extra parentheses around the cast to ensure proper operator precedence when dereferencing the OptiX ray payload pointer. This fixes the issue where the compiler was treating the expression as (RayPayload_0 *)getOptiXRayPayloadPtr()->color_0 instead of ((RayPayload_0 *)getOptiXRayPayloadPtr())->color_0. Error: nvrtc 12.9: tests/cuda/optix-cluster.slang(17): error : expression must have pointer-to-class type but it has type "void *" nvrtc 12.9: note : (RayPayload_0 *)getOptiXRayPayloadPtr()->color_0 = color_1; nvrtc 12.9: note : ^ Tested using: ./build/Debug/bin/slangc -target ptx -Xnvrtc -I"/home/haaggarwal/NVIDIA-OptiX-SDK-9.0.0-linux64-x86_64/include" -DSLANG_CUDA_ENABLE_OPTIX -entry closestHitShaderA ./tests/cuda/optix-cluster.slang * Fix Check 2025-05-17T02:06:19+00:00 Harsh Aggarwal (NVIDIA) haaggarwal@nvidia.com 2025-05-17T02:06:19+00:00 urn:sha1:0be6970c01d212aac7ea7db9b6c1556c530d6889 * Add noreturn attribute to IgnoreHit * Revert "Add noreturn attribute to IgnoreHit" This reverts commit 3cf2354dada71b9a8713b08f3a2e261de4aabfa4. * Fix: Preserve inout param modifications with OptiX IgnoreHit() Issue #6326 identified that in OptiX, when using IgnoreHit() (which maps to the "noreturn" optixIgnoreIntersection() intrinsic), any modifications made to 'inout' parameters within the shader would be lost. This was due to IgnoreHit() preventing the execution of the copy-back operation from the temporary variable (used to implement 'inout' semantics) to the original parameter. This commit introduces a new IR pass, 'undoParameterCopy', specifically for CUDA/OptiX targets to address this. The pass operates as follows: 1. Identifies temporary IR variables created for 'inout' parameters, which are now decorated with 'TempCallArgVarDecoration'. 2. Maps these temporary variables back to their original parameter storage (e.g., the OptiX payload pointer). 3. Replaces all uses of the temporary variable directly with the original parameter pointer. 4. Removes the temporary variable declaration and its initializing store (which copied from the original parameter to the temporary). By transforming the IR to operate directly on the original parameter storage before any potential call to IgnoreHit(), this fix ensures that all modifications are preserved, correctly resolving issue #6326. The pass is integrated into the compilation flow for relevant targets. * Refactor(IR): Optimize GetOptiXRayPayloadPtr for better DCE/CSE To allow for more effective dead code elimination (DCE) and common subexpression elimination (CSE) of `getOptiXRayPayloadPtr` instructions, this commit: - Marks `kIROp_GetOptiXRayPayloadPtr` as side-effect-free within `IRInst::mightHaveSideEffects` (in `slang-ir.cpp`). - Flags `GetOptiXRayPayloadPtr` as `HOISTABLE` in its definition within `slang-ir-inst-defs.h`. This addresses scenarios where multiple, potentially redundant, calls to `getOptiXRayPayloadPtr` might appear in the IR, allowing optimizers to produce cleaner and potentially more efficient code for OptiX targets. This change supports efforts to refine IR handling for ray-tracing shader stages. * Remove debugging code * Refactor UndoParameterCopyVisitor for improved performance - Optimized IR traversal by combining multiple passes into a single scan - Removed unnecessary dictionary, immediately replace uses when a temp var is found - Reduced duplicate code paths by checking for both temp vars and redundant stores in one loop - Better handling of the 'changed' flag to ensure DCE only runs when needed - Results in fewer instruction traversals and improved efficiency for large functions * Add Test