// Copyright 2021 The Dawn & Tint Authors
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#include "src/tint/utils/id/generation_id.h"

#include <atomic>

namespace tint {

namespace {

std::atomic<uint32_t> next_generation_id{1};

}  // namespace

GenerationID::GenerationID() = default;

GenerationID::GenerationID(uint32_t id) : val(id) {}

GenerationID GenerationID::New() {
    return GenerationID(next_generation_id++);
}

namespace detail {

/// AssertGenerationIDsEqual is called by TINT_ASSERT_GENERATION_IDS_EQUAL() and
/// TINT_ASSERT_GENERATION_IDS_EQUAL_IF_VALID() to assert that the GenerationIDs
/// `a` and `b` are equal.
void AssertGenerationIDsEqual(GenerationID a,
                              GenerationID b,
                              bool if_valid,
                              const char* msg,
                              const char* file,
                              size_t line) {
    if (a == b) {
        return;  // matched
    }
    if (if_valid && (!a || !b)) {
        return;  //  a or b were not valid
    }
    tint::InternalCompilerError(file, line) << msg;
}

}  // namespace detail
}  // namespace tint