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#ifndef SRC_TINT_LANG_CORE_IR_TRANSFORM_DEMOTE_TO_HELPER_H_
#define SRC_TINT_LANG_CORE_IR_TRANSFORM_DEMOTE_TO_HELPER_H_

#include <string>

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

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

namespace tint::core::ir::transform {

/// DemoteToHelper is a transform that emulates demote-to-helper semantics for discard instructions.
///
/// For backend targets that implement discard by terminating the invocation, we need to change the
/// program to ensure that discarding the fragment does not affect uniformity with respect to
/// derivative operations. We do this by setting a global flag and masking all writes to storage
/// buffers and textures.
/// @param module the module to transform
/// @returns success or failure
Result<SuccessType> DemoteToHelper(Module& module);

}  // namespace tint::core::ir::transform

#endif  // SRC_TINT_LANG_CORE_IR_TRANSFORM_DEMOTE_TO_HELPER_H_