Making it easier to work with shaders https://git.yummers.dev/slang.git/atom?h=master 2025-09-30T00:45:08+00:00 2025-09-30T00:45:08+00:00 Yong He yonghe@outlook.com 2025-09-30T00:45:08+00:00 urn:sha1:a6deb5ed82cb8fc6b4f4c5c5fee264e09f97ff89 Part of the effort to improve the performance of generated SPIRV code. The existing lower-buffer-element-type pass works by loading the entire buffer element content from memory, and translate it to logical type stored in a local variable at the earliest reference of a buffer handle. This means that is can generate inefficient code that reads more than necessary. Consider this example: ``` struct BigStruct { bool values[1024]; } ConstantBuffer<BigStruct> cb; void test(BigStruct v) { if (v.values[0]) { printf("ok"); } } [numthreads(1,1,1)] void computeMain() { test(cb); } ``` In IR, the `computeMain` function before lower-buffer-element-type pass is something like following: ``` func test: %v = param : BigStruct %barr = fieldExtract(%v, "values") %element = elementExtract(%barr, 0) ... // uses %element func computeMain: %v = load(cb) call %test %v ``` The existing lower-buffer-element-type pass will rewrite the bool array in `BigStruct` into `int` array so it is legal in SPIRV. However, it does so by inserting the translation on the first `load` of the constant buffer: ``` struct BigStruct_std430 { int values[1024]; } var cb : ConstantBuffer<BigStruct_std430>; func computeMain: %tmpVar : var<BigStruct> call %unpackStorage(%tmpVar, cb) %v : BigStruct = load %tmpVar call %test %v ``` This means that the entire array will be loaded and translated to int, before calling `test`, which only uses one element. It turns out that the downstream compiler isn't always able to optimize out this inefficient translation/copy. This PR completely rewrites the way buffer-element-type lowering is handled to avoid producing this inefficient code. It works in two parts: first we turn on the `transformParamsToConstRef` pass for SPIRV target as well, so we will translate the `test` function to take the `v` parameter as `constref`. The second part is a redesigned buffer-element-type pass that defers the storage-type to logical-type translation until a value is actually used by a `load` instruction. In this example, after `transformParamsToConstRef`, the IR is: ``` func test: %v = param : ConstRef<BigStruct> %barr = fieldAddr(%v, "values") %elementPtr = elementAddr(%barr, 0) %element = load(%elementPtr) ... // uses %element func computeMain: call %test %cb ``` The new `buffer-element-type-lowering` pass will take this IR, and insert translation at latest possible time across the entire call graph, and translate the IR into: ``` func test: %v = param : ConstRef<BigStruct_std430> %barr = fieldAddr(%v, "values") %elementPtr : ptr<int> = elementAddr(%barr, 0) %element_int = load(%elementPtr) %element = cast(%element_int) : %bool ... // uses %element func computeMain: call %test %cb ``` In this new IR, there is no longer a load and conversion of the entire array. See new comment in `slang-ir-lower-buffer-element-type.cpp` for more details of how the pass works. This PR also address many other issues surfaced by turning on `transformParamsToConstRef` pass on SPIRV backend. --------- Co-authored-by: slangbot <186143334+slangbot@users.noreply.github.com> 2025-09-03T16:06:43+00:00 Harsh Aggarwal (NVIDIA) haaggarwal@nvidia.com 2025-09-03T16:06:43+00:00 urn:sha1:bf607e2f3fa183e9a2b18c7a98438a05247d6ed3 2025-09-02T23:43:48+00:00 James Helferty (NVIDIA) jhelferty@nvidia.com 2025-09-02T23:43:48+00:00 urn:sha1:f02b08490aa905f42a8d90381db84b1f8e409c0c Changes default for render-test to sm_6_5. Since sm_6_5 is the new default, remove the -use-dxil option, add -use-dxcb option Remove -use-dxil option from all test cases. Add -use-dxcb to two tests that needed it. Fixes #7611 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 2025-03-06T22:26:34+00:00 Yong He yonghe@outlook.com 2025-03-06T22:26:34+00:00 urn:sha1:4485cf3eaf142cfd5f8470e86739acc67d4e12ea * Update SPIRV-Tools and fix new validation errors. * Implement pointers for glsl target. * Reworked packStorage/unpackStorage code gen to operate on pointers rather than values. 2025-02-28T01:54:22+00:00 Simon Kallweit 64953474+skallweitNV@users.noreply.github.com 2025-02-28T01:54:22+00:00 urn:sha1:38734ec1f6644f1565aeb91106f371b14d3ba07a * remove unused resource * define buffer data * add vs2022 build presets * update slang-rhi API usage * update slang-rhi --------- Co-authored-by: Yong He <yonghe@outlook.com> 2024-07-02T03:06:58+00:00 kaizhangNV 149626564+kaizhangNV@users.noreply.github.com 2024-07-02T03:06:58+00:00 urn:sha1:bd01bd3f4b8eecbfb924b8eb4090694e44e8166c * Fix the type error in kIROp_RWStructuredBufferLoad In StructuredBuffer::Load(), we allow any type of integer as the input. However, when emitting glsl code, StructuredBuffer::Load(index) will be translated to the subscript index of the buffer, e.g. buffer[index], however, glsl doesn't allow 64bit integer as the subscript. So the easiest fix is to convert the index to uint when emitting glsl. * Add commit 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.