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#ifndef SRC_TINT_LANG_MSL_WRITER_RAISE_PACKED_VEC3_H_
#define SRC_TINT_LANG_MSL_WRITER_RAISE_PACKED_VEC3_H_

#include "src/tint/utils/result/result.h"

// Forward declarations.
namespace tint::core::ir {
class Module;
}  // namespace tint::core::ir

namespace tint::msl::writer::raise {

/// 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.
///
/// The transform 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.
/// * Rewrite matrix types that have three rows into arrays of column vectors.
/// * Convert values that contain packed types to their original unpacked equivalents after loading
///   them from memory, and the vice versa before storing values to memory.
///
/// @param module the module to transform
/// @returns success or failure
Result<SuccessType> PackedVec3(core::ir::Module& module);

}  // namespace tint::msl::writer::raise

#endif  // SRC_TINT_LANG_MSL_WRITER_RAISE_PACKED_VEC3_H_