src/tint/lang/wgsl/sem/load.h

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#ifndef SRC_TINT_LANG_WGSL_SEM_LOAD_H_
#define SRC_TINT_LANG_WGSL_SEM_LOAD_H_

#include "src/tint/lang/core/type/reference.h"
#include "src/tint/lang/wgsl/sem/value_expression.h"

namespace tint::sem {

/// Load is a semantic expression which represents the load of a memory view to a value.
/// Loads from reference types are implicit in WGSL, so the Load semantic node shares the same AST
/// node as the inner semantic node.
class Load final : public Castable<Load, ValueExpression> {
  public:
    /// Constructor
    /// @param source the source expression being loaded from
    /// @param statement the statement that owns this expression
    /// @param stage the earliest evaluation stage for the expression
    Load(const ValueExpression* source, const Statement* statement, core::EvaluationStage stage);

    /// Destructor
    ~Load() override;

    /// @return the source object being loaded
    const ValueExpression* Source() const { return source_; }

    /// @returns the type of the memory view being loaded from.
    const core::type::MemoryView* MemoryView() const {
        return static_cast<const core::type::MemoryView*>(source_->Type());
    }

  private:
    ValueExpression const* const source_;
};

}  // namespace tint::sem

#endif  // SRC_TINT_LANG_WGSL_SEM_LOAD_H_