[VULKAN] Add support for specialization constants #499
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This commit introduces support for specialization constants in the Vulkan backend. Key changes: - Added struct to to represent a specialization constant with its ID, type, and value. - Updated YAML mapping in to parse specialization constants from the test configuration. - Modified to create and use when creating the compute pipeline, allowing specialization constants to be passed to the shader. - Added a new test case in to verify the functionality of specialization constants with various data types (bool, int, uint, float). Fixes llvm/llvm-project#142992
Keenuts
reviewed
Nov 12, 2025
| case DataFormat::Float32: { | ||
| float Value = 0.0f; | ||
| double Tmp = 0.0; | ||
| llvm::StringRef(SpecConst.Value).getAsDouble(Tmp); |
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If the string is not a valid number, this seem to return true. Shall this be checked and reported as fatal instead of silently keeping the default of 0.0f?
| llvm::SmallVector<char> SpecData; | ||
| VkSpecializationInfo SpecInfo = {}; | ||
| if (!Shader.SpecializationConstants.empty()) { | ||
| for (const auto &SpecConst : Shader.SpecializationConstants) { |
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Vulkan requires the constant ID to be unique (VUID-VkSpecializationInfo-constantID-04911). Seems like this is not enforced here, so a bad config file could lead to problems/UB at runtime depending on the VK implementation no?
| @@ -0,0 +1,87 @@ | |||
| #--- simple.hlsl | |||
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you should test we can reuse the same spec-id on the HLSL/SPIR-V side, but not in the YAML config (or at least that we correctly emit an error or something loud)
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This commit introduces support for specialization constants in the Vulkan backend.
Key changes:
Fixes llvm/llvm-project#142992