src/tint/lang/hlsl/writer/raise/promote_initializers.h

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#ifndef SRC_TINT_LANG_HLSL_WRITER_RAISE_PROMOTE_INITIALIZERS_H_
#define SRC_TINT_LANG_HLSL_WRITER_RAISE_PROMOTE_INITIALIZERS_H_

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

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

namespace tint::hlsl::writer::raise {

/// PromoteInitializers is a transform that moves inline struct and array initializers to a `let`
/// unless the initializer is already in a `let ` or `var`. For any `var` at the module scope it
/// will recursively break any array or struct initializers out of the constant into their own
/// `let`.
///
/// After this transform the `Capability::kAllowModuleScopeLets` must be enabled and any downstream
/// transform/printer must under stand `let` and `construct` instructions at the module scope.
/// (`construct` can just be skipped as they will be inlined, but the instruction still has to be
/// handled.)
///
/// For example:
///
/// ```wgsl
/// struct A {
///   b: f32,
/// }
/// struct S {
///   a: A
/// }
/// var<private> p = S(A(1.f));
/// ```
///
/// Essentially creates:
///
/// ```wgsl
/// struct S {
///   a: i32,
/// }
/// let v: A = A(1.f);
/// let v_1: S = S(v);
/// var p = v_1;
/// ```
///
/// @param module the module to transform
/// @returns error diagnostics on failure
Result<SuccessType> PromoteInitializers(core::ir::Module& module);

}  // namespace tint::hlsl::writer::raise

#endif  // SRC_TINT_LANG_HLSL_WRITER_RAISE_PROMOTE_INITIALIZERS_H_