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

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#ifndef SRC_TINT_LANG_WGSL_AST_TRANSFORM_REMOVE_PHONIES_H_
#define SRC_TINT_LANG_WGSL_AST_TRANSFORM_REMOVE_PHONIES_H_

#include <string>
#include <unordered_map>

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

namespace tint::ast::transform {

/// RemovePhonies is a Transform that removes all phony-assignment statements,
/// while preserving function call expressions in the RHS of the assignment that
/// may have side-effects. It also removes calls to builtins that return a constant value.
/// @note RemovePhonies must be run after the PromoteSideEffectsToDecl transform, otherwise `f` in
/// `_ = cond && f()` may get hoisted to a call statement without the short-circuiting conditional.
class RemovePhonies final : public Castable<RemovePhonies, Transform> {
  public:
    /// Constructor
    RemovePhonies();

    /// Destructor
    ~RemovePhonies() override;

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

}  // namespace tint::ast::transform

#endif  // SRC_TINT_LANG_WGSL_AST_TRANSFORM_REMOVE_PHONIES_H_