src/tint/lang/wgsl/ast/transform/simplify_pointers.h

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#ifndef SRC_TINT_LANG_WGSL_AST_TRANSFORM_SIMPLIFY_POINTERS_H_
#define SRC_TINT_LANG_WGSL_AST_TRANSFORM_SIMPLIFY_POINTERS_H_

#include "src/tint/lang/wgsl/ast/transform/transform.h"

namespace tint::ast::transform {

/// SimplifyPointers is a Transform that moves all usage of function-scope
/// `let` statements of a pointer type into their places of usage, while also
/// simplifying any chains of address-of or indirections operators.
///
/// Parameters of a pointer type are not adjusted.
///
/// Note: SimplifyPointers does not operate on module-scope `let`s, as these
/// cannot be pointers: https://gpuweb.github.io/gpuweb/wgsl/#module-constants
/// `A module-scope let-declared constant must be of constructible type.`
///
/// @note Depends on the following transforms to have been run first:
/// * Unshadow
class SimplifyPointers final : public Castable<SimplifyPointers, Transform> {
  public:
    /// Constructor
    SimplifyPointers();

    /// Destructor
    ~SimplifyPointers() override;

    /// @copydoc Transform::Apply
    ApplyResult Apply(const Program& program,
                      const DataMap& inputs,
                      DataMap& outputs) const override;

  private:
    struct State;
};

}  // namespace tint::ast::transform

#endif  // SRC_TINT_LANG_WGSL_AST_TRANSFORM_SIMPLIFY_POINTERS_H_