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

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#ifndef SRC_TINT_LANG_WGSL_AST_TRANSFORM_EXPAND_COMPOUND_ASSIGNMENT_H_
#define SRC_TINT_LANG_WGSL_AST_TRANSFORM_EXPAND_COMPOUND_ASSIGNMENT_H_

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

namespace tint::ast::transform {

/// Converts compound assignment statements to regular assignment statements,
/// hoisting the LHS expression if necessary.
///
/// Before:
/// ```
///   a += 1;
///   vector_array[foo()][bar()] *= 2.0;
/// ```
///
/// After:
/// ```
///   a = a + 1;
///   let _vec = &vector_array[foo()];
///   let _idx = bar();
///   (*_vec)[_idx] = (*_vec)[_idx] * 2.0;
/// ```
///
/// This transform also handles increment and decrement statements in the same
/// manner, by replacing `i++` with `i = i + 1`.
class ExpandCompoundAssignment final : public Castable<ExpandCompoundAssignment, Transform> {
  public:
    /// Constructor
    ExpandCompoundAssignment();
    /// Destructor
    ~ExpandCompoundAssignment() 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_EXPAND_COMPOUND_ASSIGNMENT_H_