src/tint/lang/msl/writer/raise/module_constant.h

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#ifndef SRC_TINT_LANG_MSL_WRITER_RAISE_MODULE_CONSTANT_H_
#define SRC_TINT_LANG_MSL_WRITER_RAISE_MODULE_CONSTANT_H_

#include "src/tint/lang/core/ir/validator.h"
#include "src/tint/utils/result.h"

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

namespace tint::msl::writer::raise {

/// The capabilities that the transform can support.
const core::ir::Capabilities kModuleConstantCapabilities{
    core::ir::Capability::kAllow8BitIntegers,
    core::ir::Capability::kAllow64BitIntegers,
    core::ir::Capability::kAllowPointersAndHandlesInStructures,
    core::ir::Capability::kAllowVectorElementPointer,
    core::ir::Capability::kAllowHandleVarsWithoutBindings,
    core::ir::Capability::kAllowClipDistancesOnF32,
    core::ir::Capability::kAllowPrivateVarsInFunctions,
    core::ir::Capability::kAllowAnyLetType,
    core::ir::Capability::kAllowNonCoreTypes,
    core::ir::Capability::kAllowWorkspacePointerInputToEntryPoint,
    core::ir::Capability::kAllowModuleScopeLets,
};

/// The set of polyfills that should be applied.
struct ModuleConstantConfig {
    // Set to true to disable module constant transform on constant data that has any f16.
    bool disable_module_constant_f16 = false;
};

/// ModuleConstant is a transform that moves all const data associated with access to a module scope
/// let. This transform is used to support 'program scope constants' in msl and thereby avoid the
/// potential for copying of large const in nested loops.
/// @param module the module to transform
/// @returns success or failure
Result<SuccessType> ModuleConstant(core::ir::Module& module, const ModuleConstantConfig& config);

}  // namespace tint::msl::writer::raise

#endif  // SRC_TINT_LANG_MSL_WRITER_RAISE_MODULE_CONSTANT_H_