| // Copyright 2021 The Tint Authors. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #ifndef SRC_TINT_TRANSFORM_ARRAY_LENGTH_FROM_UNIFORM_H_ |
| #define SRC_TINT_TRANSFORM_ARRAY_LENGTH_FROM_UNIFORM_H_ |
| |
| #include <unordered_map> |
| #include <unordered_set> |
| |
| #include "src/tint/sem/binding_point.h" |
| #include "src/tint/transform/transform.h" |
| |
| // Forward declarations |
| namespace tint { |
| class CloneContext; |
| } // namespace tint |
| |
| namespace tint::transform { |
| |
| /// ArrayLengthFromUniform is a transform that implements calls to arrayLength() |
| /// by calculating the length from the total size of the storage buffer, which |
| /// is received via a uniform buffer. |
| /// |
| /// The generated uniform buffer will have the form: |
| /// ``` |
| /// struct buffer_size_struct { |
| /// buffer_size : array<u32, 8>; |
| /// }; |
| /// |
| /// @group(0) @binding(30) |
| /// var<uniform> buffer_size_ubo : buffer_size_struct; |
| /// ``` |
| /// The binding group and number used for this uniform buffer is provided via |
| /// the `Config` transform input. The `Config` struct also defines the mapping |
| /// from a storage buffer's `BindingPoint` to the array index that will be used |
| /// to get the size of that buffer. |
| /// |
| /// This transform assumes that the `SimplifyPointers` |
| /// transforms have been run before it so that arguments to the arrayLength |
| /// builtin always have the form `&resource.array`. |
| /// |
| /// @note Depends on the following transforms to have been run first: |
| /// * SimplifyPointers |
| class ArrayLengthFromUniform final |
| : public Castable<ArrayLengthFromUniform, Transform> { |
| public: |
| /// Constructor |
| ArrayLengthFromUniform(); |
| /// Destructor |
| ~ArrayLengthFromUniform() override; |
| |
| /// Configuration options for the ArrayLengthFromUniform transform. |
| struct Config final : public Castable<Data, transform::Data> { |
| /// Constructor |
| /// @param ubo_bp the binding point to use for the generated uniform buffer. |
| explicit Config(sem::BindingPoint ubo_bp); |
| |
| /// Copy constructor |
| Config(const Config&); |
| |
| /// Copy assignment |
| /// @return this Config |
| Config& operator=(const Config&); |
| |
| /// Destructor |
| ~Config() override; |
| |
| /// The binding point to use for the generated uniform buffer. |
| sem::BindingPoint ubo_binding; |
| |
| /// The mapping from binding point to the index for the buffer size lookup. |
| std::unordered_map<sem::BindingPoint, uint32_t> bindpoint_to_size_index; |
| }; |
| |
| /// Information produced about what the transform did. |
| /// If there were no calls to the arrayLength() builtin, then no Result will |
| /// be emitted. |
| struct Result final : public Castable<Result, transform::Data> { |
| /// Constructor |
| /// @param used_size_indices Indices into the UBO that are statically used. |
| explicit Result(std::unordered_set<uint32_t> used_size_indices); |
| |
| /// Copy constructor |
| Result(const Result&); |
| |
| /// Destructor |
| ~Result() override; |
| |
| /// Indices into the UBO that are statically used. |
| std::unordered_set<uint32_t> used_size_indices; |
| }; |
| |
| /// @param program the program to inspect |
| /// @param data optional extra transform-specific input data |
| /// @returns true if this transform should be run for the given program |
| bool ShouldRun(const Program* program, |
| const DataMap& data = {}) const override; |
| |
| protected: |
| /// Runs the transform using the CloneContext built for transforming a |
| /// program. Run() is responsible for calling Clone() on the CloneContext. |
| /// @param ctx the CloneContext primed with the input program and |
| /// ProgramBuilder |
| /// @param inputs optional extra transform-specific input data |
| /// @param outputs optional extra transform-specific output data |
| void Run(CloneContext& ctx, |
| const DataMap& inputs, |
| DataMap& outputs) const override; |
| }; |
| |
| } // namespace tint::transform |
| |
| #endif // SRC_TINT_TRANSFORM_ARRAY_LENGTH_FROM_UNIFORM_H_ |