// Copyright 2022 The Dawn & Tint Authors // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are met: // // 1. Redistributions of source code must retain the above copyright notice, this // list of conditions and the following disclaimer. // // 2. Redistributions in binary form must reproduce the above copyright notice, // this list of conditions and the following disclaimer in the documentation // and/or other materials provided with the distribution. // // 3. Neither the name of the copyright holder nor the names of its // contributors may be used to endorse or promote products derived from // this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. #ifndef SRC_TINT_LANG_MSL_WRITER_AST_RAISE_PACKED_VEC3_H_ #define SRC_TINT_LANG_MSL_WRITER_AST_RAISE_PACKED_VEC3_H_ #include "src/tint/lang/wgsl/ast/transform/transform.h" namespace tint::msl::writer { /// A transform to be used by the MSL backend which will: /// * Replace `vec3<T>` types with an internal `__packed_vec3` type when they are used in /// host-shareable address spaces. /// * Wrap generated `__packed_vec3` types in a structure when they are used in arrays, so that we /// ensure that the array has the correct element stride. /// * Multi-version structures that contain `vec3<T>` types when they are used in host-shareable /// memory, to avoid modifying uses in other address spaces. /// * Rewrite matrix types that have three rows into arrays of column vectors. /// * Insert calls to helper functions to convert expressions that use these types to or from the /// regular vec3 types when accessing host-shareable memory. /// * Cast all direct (not sub-accessed) loads of these packed vectors to the 'unpacked' vec3<T> /// type before usage. /// /// This transform is necessary in order to emit vec3 types with the correct size (so that scalars /// can follow them in structures), and also to ensure that padding bytes are preserved when writing /// to a vec3, an array of vec3 elements, or a matrix with vec3 column type. /// /// @note Depends on the following transforms to have been run first: /// * ExpandCompoundAssignment class PackedVec3 final : public Castable<PackedVec3, ast::transform::Transform> { … }; } // namespace tint::msl::writer #endif // SRC_TINT_LANG_MSL_WRITER_AST_RAISE_PACKED_VEC3_H_