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

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#ifndef SRC_TINT_LANG_WGSL_SEM_ARRAY_COUNT_H_
#define SRC_TINT_LANG_WGSL_SEM_ARRAY_COUNT_H_

#include <string>

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

namespace tint::sem {

/// The variant of an ArrayCount when the count is a named override variable.
/// Example:
/// ```
/// override N : i32;
/// type arr = array<i32, N>
/// ```
class NamedOverrideArrayCount final
    : public Castable<NamedOverrideArrayCount, core::type::ArrayCount> {
  public:
    /// Constructor
    /// @param var the `override` variable
    explicit NamedOverrideArrayCount(const GlobalVariable* var);
    ~NamedOverrideArrayCount() override;

    /// @param other the other node
    /// @returns true if this array count is equal @p other
    bool Equals(const core::type::UniqueNode& other) const override;

    /// @returns the friendly name for this array count
    std::string FriendlyName() const override;

    /// @param ctx the clone context
    /// @returns a clone of this type
    core::type::ArrayCount* Clone(core::type::CloneContext& ctx) const override;

    /// The `override` variable.
    const GlobalVariable* variable;
};

/// The variant of an ArrayCount when the count is an unnamed override variable.
/// Example:
/// ```
/// override N : i32;
/// type arr = array<i32, N*2>
/// ```
class UnnamedOverrideArrayCount final
    : public Castable<UnnamedOverrideArrayCount, core::type::ArrayCount> {
  public:
    /// Constructor
    /// @param e the override expression
    explicit UnnamedOverrideArrayCount(const ValueExpression* e);
    ~UnnamedOverrideArrayCount() override;

    /// @param other the other node
    /// @returns true if this array count is equal @p other
    bool Equals(const core::type::UniqueNode& other) const override;

    /// @returns the friendly name for this array count
    std::string FriendlyName() const override;

    /// @param ctx the clone context
    /// @returns a clone of this type
    core::type::ArrayCount* Clone(core::type::CloneContext& ctx) const override;

    /// The unnamed override expression.
    /// Note: Each AST expression gets a unique semantic expression node, so two equivalent AST
    /// expressions will not result in the same `expr` pointer. This property is important to ensure
    /// that two array declarations with equivalent AST expressions do not compare equal.
    /// For example, consider:
    /// ```
    /// override size : u32;
    /// var<workgroup> a : array<f32, size * 2>;
    /// var<workgroup> b : array<f32, size * 2>;
    /// ```
    // The array count for `a` and `b` have equivalent AST expressions, but the types for `a` and
    // `b` must not compare equal.
    const ValueExpression* expr;
};

}  // namespace tint::sem

#endif  // SRC_TINT_LANG_WGSL_SEM_ARRAY_COUNT_H_