validation.cpp::GetBlockSubsidy

获得当前nHeight高度的挖矿收入，每nSubsidyHalvingInterval减半
CAmount GetBlockSubsidy(int nHeight, const Consensus::Params& consensusParams)
{
    //consensus.nSubsidyHalvingInterval = 210000;
    int halvings = nHeight / consensusParams.nSubsidyHalvingInterval;

    // Force block reward to zero when right shift is undefined.
    if (halvings >= 64)
        return 0;
        
    CAmount nSubsidy = 50 * COIN;
    // Subsidy is cut in half every 210,000 blocks which will occur approximately every 4 years.
    nSubsidy >>= halvings;
    return nSubsidy;
}

/** Amount in satoshis (Can be negative) */
typedef int64_t CAmount;

static const CAmount COIN = 100000000;
static const CAmount CENT = 1000000;

/** No amount larger than this (in satoshi) is valid.
*
* Note that this constant is *not* the total money supply, which in Bitcoin
* currently happens to be less than 21,000,000 BTC for various reasons, but
* rather a sanity check. As this sanity check is used by consensus-critical
* validation code, the exact value of the MAX_MONEY constant is consensus
* critical; in unusual circumstances like a(nother) overflow bug that allowed
* for the creation of coins out of thin air modification could lead to a fork.
* */
static const CAmount MAX_MONEY = 21000000 * COIN;
inline bool MoneyRange(const CAmount& nValue) { return (nValue >= 0 && nValue <= MAX_MONEY); }