Making it easier to work with shaders https://git.yummers.dev/slang.git/atom?h=master 2025-08-05T12:34:18+00:00 2025-08-05T12:34:18+00:00 Harsh Aggarwal (NVIDIA) haaggarwal@nvidia.com 2025-08-05T12:34:18+00:00 urn:sha1:9a16700e858fc0379e551ab72188eb63a54ad3f1 2025-05-16T17:42:59+00:00 Darren Wihandi 65404740+fairywreath@users.noreply.github.com 2025-05-16T17:42:59+00:00 urn:sha1:8683b85c0494db99feb08b6efcdc26dfe006729f * Fix HLSL ByteAddressBuffer Load* parameter integer type * Fix tests * Fix load with alignment function signature clash * Fix LoadAligned tests 2024-05-14T06:57:57+00:00 Sriram Murali 85252063+sriramm-nv@users.noreply.github.com 2024-05-14T06:57:57+00:00 urn:sha1:487ae034e2b03ddd67945132c8fecbd937952705 Fixes #4062 This change enables wide load/stores for byte-address-buffer backed resources, when the data is accessed at an offset that is aligned. **Goals** - Improve performance by issuing wider instructions instead of sequence of scalar instructions, for load and stores of byte-address buffers. - Reduce code-size and readability of the generated shaders. - Help naive users as well as ninja programmers, generate optimal code. **Non Goals** - Help with Structured buffers, or other resources. - Target compilation time improvements. **Key changes** Adds 2 new overloads for Load and Store operations on ByteAddress Buffers. 1. Load / Store with an extra alignment parameter ``` resource.Load<T>(offset, alignment); resource.Store<T>(offset, value, alignment); ``` 2. LoadAligned / StoreAligned with no extra parameter, with the same signature as orignial Load / Store. ``` resource.LoadAligned<T>(offset); resource.StoreAligned<T>(offset, value); ``` - This overload will implicitly identify the alignment value, from the base type T of the elementary unit of the resource. **Supported resources** 1. Vectors This can be upto 4 elements, i.e. float -- float4. 2. Arrays This does not have a limit on number of elements, but on a conservative estimate, we can limit to few hundreds. 3. Structures This is used to group a resource of a single type. ``` struct { float4 x; } ``` **Code updates** - Modified byte-address-ir legalize to handle struct, array and vector kinds of load or store access - Added custom hlsl stdlib functions to implement all the overloads for Load, Store etc. - Added C-like emitter, SPIR-V emitter for handling ByteAddressBuffers. - Added a new core stdlib function intrinsic to wrap around alignOf<T>(). - Added a new peephole optimization entry to identify the equivalent IntLiteral value from the alignOf<T>() inst. - Added tests to check explicit, and implicit aligned Load and Store operations.