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consensus/params: Move version bits period/threshold to bip9 param

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Rather than having the rule change period/threshold be constant for all
potential deployments on a chain, have it be specific to the deployment
itself. This both matches history (BIP 9 specified a 2016 block period
and 1916 block threshold; BIP 91 specified a 336 block period and 269
block threshold; and BIP 341 specified a 2016 block period and 1815
block threshold), and allows the code to be simplified, as only the
BIP9Deployment structure is needed, not the full Consensus::Params
structure.
This commit is contained in:
Anthony Towns 2023-12-07 12:16:22 +10:00
parent e9d617095d
commit a679040ec1
5 changed files with 76 additions and 45 deletions
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15
src/consensus/params.h
View file

@ -53,6 +53,14 @@ struct BIP9Deployment {
* boundary.
*/
int min_activation_height{0};
/** Period of blocks to check signalling in (usually retarget period, ie params.DifficultyAdjustmentInterval()) */
uint32_t period{2016};
/**
* Minimum blocks including miner confirmation of the total of 2016 blocks in a retargeting period,
* which is also used for BIP9 deployments.
* Examples: 1916 for 95%, 1512 for testchains.
*/
uint32_t threshold{1916};
/** Constant for nTimeout very far in the future. */
static constexpr int64_t NO_TIMEOUT = std::numeric_limits<int64_t>::max();
@ -98,13 +106,6 @@ struct Params {
/** Don't warn about unknown BIP 9 activations below this height.
* This prevents us from warning about the CSV and segwit activations. */
int MinBIP9WarningHeight;
/**
* Minimum blocks including miner confirmation of the total of 2016 blocks in a retargeting period,
* (nPowTargetTimespan / nPowTargetSpacing) which is also used for BIP9 deployments.
* Examples: 1916 for 95%, 1512 for testchains.
*/
uint32_t nRuleChangeActivationThreshold;
uint32_t nMinerConfirmationWindow;
std::array<BIP9Deployment,MAX_VERSION_BITS_DEPLOYMENTS> vDeployments;
/** Proof of work parameters */
uint256 powLimit;

31
src/kernel/chainparams.cpp
View file

@ -104,18 +104,20 @@ public:
consensus.fPowAllowMinDifficultyBlocks = false;
consensus.enforce_BIP94 = false;
consensus.fPowNoRetargeting = false;
consensus.nRuleChangeActivationThreshold = 1815; // 90% of 2016
consensus.nMinerConfirmationWindow = 2016; // nPowTargetTimespan / nPowTargetSpacing
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].bit = 28;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = Consensus::BIP9Deployment::NEVER_ACTIVE;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].min_activation_height = 0; // No activation delay
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].threshold = 1815; // 90%
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].period = 2016;
// Deployment of Taproot (BIPs 340-342)
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].bit = 2;
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = 1619222400; // April 24th, 2021
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = 1628640000; // August 11th, 2021
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].min_activation_height = 709632; // Approximately November 12th, 2021
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].threshold = 1815; // 90%
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].period = 2016;
consensus.nMinimumChainWork = uint256{"000000000000000000000000000000000000000088e186b70e0862c193ec44d6"};
consensus.defaultAssumeValid = uint256{"000000000000000000011c5890365bdbe5d25b97ce0057589acaef4f1a57263f"}; // 856760
@ -228,18 +230,20 @@ public:
consensus.fPowAllowMinDifficultyBlocks = true;
consensus.enforce_BIP94 = false;
consensus.fPowNoRetargeting = false;
consensus.nRuleChangeActivationThreshold = 1512; // 75% for testchains
consensus.nMinerConfirmationWindow = 2016; // nPowTargetTimespan / nPowTargetSpacing
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].bit = 28;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = Consensus::BIP9Deployment::NEVER_ACTIVE;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].min_activation_height = 0; // No activation delay
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].threshold = 1512; // 75%
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].period = 2016;
// Deployment of Taproot (BIPs 340-342)
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].bit = 2;
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = 1619222400; // April 24th, 2021
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = 1628640000; // August 11th, 2021
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].min_activation_height = 0; // No activation delay
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].threshold = 1512; // 75%
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].period = 2016;
consensus.nMinimumChainWork = uint256{"000000000000000000000000000000000000000000000f209695166be8b61fa9"};
consensus.defaultAssumeValid = uint256{"000000000000000465b1a66c9f386308e8c75acef9201f3f577811da09fc90ad"}; // 2873500
@ -327,18 +331,21 @@ public:
consensus.fPowAllowMinDifficultyBlocks = true;
consensus.enforce_BIP94 = true;
consensus.fPowNoRetargeting = false;
consensus.nRuleChangeActivationThreshold = 1512; // 75% for testchains
consensus.nMinerConfirmationWindow = 2016; // nPowTargetTimespan / nPowTargetSpacing
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].bit = 28;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = Consensus::BIP9Deployment::NEVER_ACTIVE;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].min_activation_height = 0; // No activation delay
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].threshold = 1512; // 75%
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].period = 2016;
// Deployment of Taproot (BIPs 340-342)
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].bit = 2;
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = Consensus::BIP9Deployment::ALWAYS_ACTIVE;
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].min_activation_height = 0; // No activation delay
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].threshold = 1512; // 75%
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].period = 2016;
consensus.nMinimumChainWork = uint256{"00000000000000000000000000000000000000000000005faa15d02e6202f3ba"};
consensus.defaultAssumeValid = uint256{"000000005be348057db991fa5d89fe7c4695b667cfb311391a8db374b6f681fd"}; // 39550
@ -465,20 +472,22 @@ public:
consensus.fPowAllowMinDifficultyBlocks = false;
consensus.enforce_BIP94 = false;
consensus.fPowNoRetargeting = false;
consensus.nRuleChangeActivationThreshold = 1815; // 90% of 2016
consensus.nMinerConfirmationWindow = 2016; // nPowTargetTimespan / nPowTargetSpacing
consensus.MinBIP9WarningHeight = 0;
consensus.powLimit = uint256{"00000377ae000000000000000000000000000000000000000000000000000000"};
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].bit = 28;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = Consensus::BIP9Deployment::NEVER_ACTIVE;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].min_activation_height = 0; // No activation delay
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].threshold = 1815; // 90%
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].period = 2016;
// Activation of Taproot (BIPs 340-342)
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].bit = 2;
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = Consensus::BIP9Deployment::ALWAYS_ACTIVE;
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].min_activation_height = 0; // No activation delay
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].threshold = 1815; // 90%
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].period = 2016;
// message start is defined as the first 4 bytes of the sha256d of the block script
HashWriter h{};
@ -544,18 +553,20 @@ public:
consensus.fPowAllowMinDifficultyBlocks = true;
consensus.enforce_BIP94 = opts.enforce_bip94;
consensus.fPowNoRetargeting = true;
consensus.nRuleChangeActivationThreshold = 108; // 75% for testchains
consensus.nMinerConfirmationWindow = 144; // Faster than normal for regtest (144 instead of 2016)
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].bit = 28;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = 0;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].min_activation_height = 0; // No activation delay
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].threshold = 108; // 75%
consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].period = 144; // Faster than normal for regtest (144 instead of 2016)
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].bit = 2;
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = Consensus::BIP9Deployment::ALWAYS_ACTIVE;
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].min_activation_height = 0; // No activation delay
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].threshold = 108; // 75%
consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].period = 144;
consensus.nMinimumChainWork = uint256{};
consensus.defaultAssumeValid = uint256{};

40
src/test/versionbits_tests.cpp
View file

@ -268,6 +268,12 @@ void check_computeblockversion(VersionBitsCache& versionbitscache, const Consens
int64_t nStartTime = params.vDeployments[dep].nStartTime;
int64_t nTimeout = params.vDeployments[dep].nTimeout;
int min_activation_height = params.vDeployments[dep].min_activation_height;
uint32_t period = params.vDeployments[dep].period;
uint32_t threshold = params.vDeployments[dep].threshold;
BOOST_REQUIRE(period > 0); // no division by zero, thankyou
BOOST_REQUIRE(0 < threshold); // must be able to have a window that doesn't activate
BOOST_REQUIRE(threshold < period); // must be able to have a window that does activate
// should not be any signalling for first block
BOOST_CHECK_EQUAL(versionbitscache.ComputeBlockVersion(nullptr, params), VERSIONBITS_TOP_BITS);
@ -289,7 +295,7 @@ void check_computeblockversion(VersionBitsCache& versionbitscache, const Consens
BOOST_REQUIRE(((1 << bit) & VERSIONBITS_TOP_MASK) == 0);
BOOST_REQUIRE(min_activation_height >= 0);
// Check min_activation_height is on a retarget boundary
BOOST_REQUIRE_EQUAL(min_activation_height % params.nMinerConfirmationWindow, 0U);
BOOST_REQUIRE_EQUAL(min_activation_height % period, 0U);
const uint32_t bitmask{versionbitscache.Mask(params, dep)};
BOOST_CHECK_EQUAL(bitmask, uint32_t{1} << bit);
@ -309,9 +315,9 @@ void check_computeblockversion(VersionBitsCache& versionbitscache, const Consens
// since CBlockIndex::nTime is uint32_t we can't represent any
// earlier time, so will transition from DEFINED to STARTED at the
// end of the first period by mining blocks at nTime == 0
lastBlock = firstChain.Mine(params.nMinerConfirmationWindow - 1, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
lastBlock = firstChain.Mine(period - 1, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
BOOST_CHECK_EQUAL(versionbitscache.ComputeBlockVersion(lastBlock, params) & (1 << bit), 0);
lastBlock = firstChain.Mine(params.nMinerConfirmationWindow, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
lastBlock = firstChain.Mine(period, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
BOOST_CHECK((versionbitscache.ComputeBlockVersion(lastBlock, params) & (1 << bit)) != 0);
// then we'll keep mining at nStartTime...
} else {
@ -319,25 +325,25 @@ void check_computeblockversion(VersionBitsCache& versionbitscache, const Consens
--nTime;
// Start generating blocks before nStartTime
lastBlock = firstChain.Mine(params.nMinerConfirmationWindow, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
lastBlock = firstChain.Mine(period, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
BOOST_CHECK_EQUAL(versionbitscache.ComputeBlockVersion(lastBlock, params) & (1 << bit), 0);
// Mine more blocks (4 less than the adjustment period) at the old time, and check that CBV isn't setting the bit yet.
for (uint32_t i = 1; i < params.nMinerConfirmationWindow - 4; i++) {
lastBlock = firstChain.Mine(params.nMinerConfirmationWindow + i, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
for (uint32_t i = 1; i < period - 4; i++) {
lastBlock = firstChain.Mine(period + i, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
BOOST_CHECK_EQUAL(versionbitscache.ComputeBlockVersion(lastBlock, params) & (1 << bit), 0);
}
// Now mine 5 more blocks at the start time -- MTP should not have passed yet, so
// CBV should still not yet set the bit.
nTime = nStartTime;
for (uint32_t i = params.nMinerConfirmationWindow - 4; i <= params.nMinerConfirmationWindow; i++) {
lastBlock = firstChain.Mine(params.nMinerConfirmationWindow + i, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
for (uint32_t i = period - 4; i <= period; i++) {
lastBlock = firstChain.Mine(period + i, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
BOOST_CHECK_EQUAL(versionbitscache.ComputeBlockVersion(lastBlock, params) & (1 << bit), 0);
}
// Next we will advance to the next period and transition to STARTED,
}
lastBlock = firstChain.Mine(params.nMinerConfirmationWindow * 3, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
lastBlock = firstChain.Mine(period * 3, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
// so ComputeBlockVersion should now set the bit,
BOOST_CHECK((versionbitscache.ComputeBlockVersion(lastBlock, params) & (1 << bit)) != 0);
// and should also be using the VERSIONBITS_TOP_BITS.
@ -345,8 +351,8 @@ void check_computeblockversion(VersionBitsCache& versionbitscache, const Consens
// Check that ComputeBlockVersion will set the bit until nTimeout
nTime += 600;
uint32_t blocksToMine = params.nMinerConfirmationWindow * 2; // test blocks for up to 2 time periods
uint32_t nHeight = params.nMinerConfirmationWindow * 3;
uint32_t blocksToMine = period * 2; // test blocks for up to 2 time periods
uint32_t nHeight = period * 3;
// These blocks are all before nTimeout is reached.
while (nTime < nTimeout && blocksToMine > 0) {
lastBlock = firstChain.Mine(nHeight+1, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
@ -363,7 +369,7 @@ void check_computeblockversion(VersionBitsCache& versionbitscache, const Consens
nTime = nTimeout;
// finish the last period before we start timing out
while (nHeight % params.nMinerConfirmationWindow != 0) {
while (nHeight % period != 0) {
lastBlock = firstChain.Mine(nHeight+1, nTime - 1, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
BOOST_CHECK((versionbitscache.ComputeBlockVersion(lastBlock, params) & (1 << bit)) != 0);
nHeight += 1;
@ -371,7 +377,7 @@ void check_computeblockversion(VersionBitsCache& versionbitscache, const Consens
// FAILED is only triggered at the end of a period, so CBV should be setting
// the bit until the period transition.
for (uint32_t i = 0; i < params.nMinerConfirmationWindow - 1; i++) {
for (uint32_t i = 0; i < period - 1; i++) {
lastBlock = firstChain.Mine(nHeight+1, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
BOOST_CHECK((versionbitscache.ComputeBlockVersion(lastBlock, params) & (1 << bit)) != 0);
nHeight += 1;
@ -388,20 +394,20 @@ void check_computeblockversion(VersionBitsCache& versionbitscache, const Consens
// Mine one period worth of blocks, and check that the bit will be on for the
// next period.
lastBlock = secondChain.Mine(params.nMinerConfirmationWindow, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
lastBlock = secondChain.Mine(period, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
BOOST_CHECK((versionbitscache.ComputeBlockVersion(lastBlock, params) & (1 << bit)) != 0);
// Mine another period worth of blocks, signaling the new bit.
lastBlock = secondChain.Mine(params.nMinerConfirmationWindow * 2, nTime, VERSIONBITS_TOP_BITS | (1<<bit)).Tip();
lastBlock = secondChain.Mine(period * 2, nTime, VERSIONBITS_TOP_BITS | (1<<bit)).Tip();
// After one period of setting the bit on each block, it should have locked in.
// We keep setting the bit for one more period though, until activation.
BOOST_CHECK((versionbitscache.ComputeBlockVersion(lastBlock, params) & (1 << bit)) != 0);
// Now check that we keep mining the block until the end of this period, and
// then stop at the beginning of the next period.
lastBlock = secondChain.Mine((params.nMinerConfirmationWindow * 3) - 1, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
lastBlock = secondChain.Mine((period * 3) - 1, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
BOOST_CHECK((versionbitscache.ComputeBlockVersion(lastBlock, params) & (1 << bit)) != 0);
lastBlock = secondChain.Mine(params.nMinerConfirmationWindow * 3, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
lastBlock = secondChain.Mine(period * 3, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
if (lastBlock->nHeight + 1 < min_activation_height) {
// check signalling continues while min_activation_height is not reached

16
src/validation.cpp
View file

@ -2378,8 +2378,20 @@ public:
int64_t BeginTime() const override { return 0; }
int64_t EndTime() const override { return std::numeric_limits<int64_t>::max(); }
int Period() const override { return m_chainman.GetConsensus().nMinerConfirmationWindow; }
int Threshold() const override { return m_chainman.GetConsensus().nRuleChangeActivationThreshold; }
int Period() const override {
if (m_chainman.GetParams().IsTestChain()) {
return m_chainman.GetConsensus().DifficultyAdjustmentInterval();
} else {
return 2016;
}
}
int Threshold() const override {
if (m_chainman.GetParams().IsTestChain()) {
return m_chainman.GetConsensus().DifficultyAdjustmentInterval() * 3 / 4; // 75% for test nets per BIP9 suggestion
} else {
return 1815; // 90% threshold used in BIP 341
}
}
bool Condition(const CBlockIndex* pindex) const override
{

19
src/versionbits.cpp
View file

@ -179,15 +179,14 @@ namespace
*/
class VersionBitsConditionChecker : public AbstractThresholdConditionChecker {
private:
const Consensus::Params& params;
const Consensus::DeploymentPos id;
const Consensus::BIP9Deployment& dep;
protected:
int64_t BeginTime() const override { return params.vDeployments[id].nStartTime; }
int64_t EndTime() const override { return params.vDeployments[id].nTimeout; }
int MinActivationHeight() const override { return params.vDeployments[id].min_activation_height; }
int Period() const override { return params.nMinerConfirmationWindow; }
int Threshold() const override { return params.nRuleChangeActivationThreshold; }
int64_t BeginTime() const override { return dep.nStartTime; }
int64_t EndTime() const override { return dep.nTimeout; }
int MinActivationHeight() const override { return dep.min_activation_height; }
int Period() const override { return dep.period; }
int Threshold() const override { return dep.threshold; }
bool Condition(const CBlockIndex* pindex) const override
{
@ -195,8 +194,10 @@ protected:
}
public:
explicit VersionBitsConditionChecker(const Consensus::Params& params, Consensus::DeploymentPos id) : params{params}, id{id} {}
uint32_t Mask() const { return (uint32_t{1}) << params.vDeployments[id].bit; }
explicit VersionBitsConditionChecker(const Consensus::BIP9Deployment& dep) : dep{dep} {}
explicit VersionBitsConditionChecker(const Consensus::Params& params, Consensus::DeploymentPos id) : VersionBitsConditionChecker{params.vDeployments[id]} {}
uint32_t Mask() const { return (uint32_t{1}) << dep.bit; }
};
} // namespace