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#include "src/tint/lang/core/ir/transform/add_empty_entry_point.h"

#include <utility>

#include "src/tint/lang/core/ir/builder.h"
#include "src/tint/lang/core/ir/module.h"
#include "src/tint/lang/core/ir/validator.h"

namespace tint::core::ir::transform {

namespace {

void Run(ir::Module& ir) {
    for (auto* func : ir.functions) {
        if (func->Stage() != Function::PipelineStage::kUndefined) {
            return;
        }
    }

    ir::Builder builder{ir};
    auto* ep = builder.Function("unused_entry_point", ir.Types().void_(),
                                Function::PipelineStage::kCompute, std::array{1u, 1u, 1u});
    ep->Block()->Append(builder.Return(ep));
}

}  // namespace

Result<SuccessType> AddEmptyEntryPoint(Module& ir) {
    auto result = ValidateAndDumpIfNeeded(ir, "AddEmptyEntryPoint transform");
    if (!result) {
        return result.Failure();
    }

    Run(ir);

    return Success;
}

}  // namespace tint::core::ir::transform