Better IBD fix.

Fixed randomX computation.

src/bitcoin-tx.cpp

@@ -33,12 +33,8 @@ static const int CONTINUE_EXECUTION=-1;
 
 // To fix the chainActive not defined error.
 CChain chainActive;
-struct BlockHasher
-{
-    size_t operator()(const uint256& hash) const { return hash.GetCheapHash(); }
-};
-typedef std::unordered_map<uint256, CBlockIndex*, BlockHasher> BlockMap;
-BlockMap mapBlockIndex;
+typedef std::map<uint64_t, CBlockIndex*> BlockSeedHeightMap;
+BlockSeedHeightMap mapBlockSeedHeight;
 
 //
 // This function returns either one of EXIT_ codes when it's expected to stop the process or

src/cn_utils/crypto/hash-ops.h

@@ -93,5 +93,6 @@ void rx_slow_hash_allocate_state(void);
 void rx_slow_hash_free_state(void);
 uint64_t rx_seedheight(const uint64_t height);
 void rx_seedheights(const uint64_t height, uint64_t *seed_height, uint64_t *next_height);
+int is_a_seed_height(const uint64_t height);
 void rx_slow_hash(const uint64_t mainheight, const uint64_t seedheight, const char *seedhash, const void *data, size_t length, char *hash, int miners, int is_alt);
 void rx_reorg(const uint64_t split_height);

src/cn_utils/crypto/rx-slow-hash.c

@@ -139,6 +139,11 @@ void rx_seedheights(const uint64_t height, uint64_t *seedheight, uint64_t *nexth
   *nextheight = rx_seedheight(height + SEEDHASH_EPOCH_LAG);
 }
 
+int is_a_seed_height(const uint64_t height) {
+    uint64_t next_seed_hegith = rx_seedheight(height + SEEDHASH_EPOCH_LAG + 1);
+    return (height == next_seed_hegith);
+}
+
 typedef struct seedinfo {
   randomx_cache *si_cache;
   unsigned long si_start;

src/primitives/block.cpp

@@ -17,50 +17,14 @@
 extern "C" void cn_slow_hash(const void *data, size_t length, char *hash, int variant, int prehashed, uint64_t height);
 extern "C" void cn_fast_hash(const void *data, size_t length, char *hash);
 
-namespace
-{
-    boost::mutex max_concurrency_lock;
-    unsigned max_concurrency = boost::thread::hardware_concurrency();
-}
-
-void set_max_concurrency(unsigned n)
-{
-    if (n < 1)
-        n = boost::thread::hardware_concurrency();
-    unsigned hwc = boost::thread::hardware_concurrency();
-    if (n > hwc)
-        n = hwc;
-    boost::lock_guard<boost::mutex> lock(max_concurrency_lock);
-    max_concurrency = n;
-}
-
-unsigned get_max_concurrency()
-{
-    boost::lock_guard<boost::mutex> lock(max_concurrency_lock);
-    return max_concurrency;
-}
-
 static uint256 cn_get_block_hash_by_height(uint64_t seed_height, char cnHash[32])
 {
     CBlockIndex* pblockindex = chainActive[seed_height];
     if (pblockindex == NULL) {
         // This will only happens during initial block download.
-        static std::map<uint64_t, CBlockIndex*> mapBlockHeight;
-        std::map<uint64_t, CBlockIndex*>::iterator iter = mapBlockHeight.find(seed_height);
-        if (iter != mapBlockHeight.end()) {
-            pblockindex = iter->second;
-        } else {
-            for (const std::pair<uint256, CBlockIndex*>& item : mapBlockIndex)
-            {
-                CBlockIndex* pindex = item.second;
-                if (pindex->nNonce == seed_height) {
-                    pblockindex = pindex;
-                    mapBlockHeight.insert(std::make_pair(seed_height, pindex));
-                    break;
-                }
-            }
-        }
+        pblockindex = mapBlockSeedHeight.find(seed_height)->second;
     }
+    assert(pblockindex != NULL);
     uint256 blockHash = pblockindex->GetBlockHash();
     const unsigned char* pHash = blockHash.begin();
     for (int j = 31; j >= 0; j--) {
@@ -109,7 +73,7 @@ uint256 CBlockHeader::GetPoWHash() const
         char cnHash[32];
         seed_height = crypto::rx_seedheight(height);
         cn_get_block_hash_by_height(seed_height, cnHash);
-        crypto::rx_slow_hash(height, seed_height, cnHash, blob.data(), blob.size(), BEGIN(thash), get_max_concurrency(), 0);
+        crypto::rx_slow_hash(height, seed_height, cnHash, blob.data(), blob.size(), BEGIN(thash), 0, 0);
     } else {
         cn_slow_hash(blob.data(), blob.size(), BEGIN(thash), cnHeader.major_version - 6, 0, height);
     }

src/validation.cpp

@@ -154,6 +154,7 @@ public:
     CChain chainActive;
     BlockMap mapBlockIndex;
     std::multimap<CBlockIndex*, CBlockIndex*> mapBlocksUnlinked;
+    BlockSeedHeightMap mapBlockSeedHeight;
     CBlockIndex *pindexBestInvalid = nullptr;
 
     bool LoadBlockIndex(const Consensus::Params& consensus_params, CBlockTreeDB& blocktree);
@@ -206,6 +207,7 @@ private:
 CCriticalSection cs_main;
 
 BlockMap& mapBlockIndex = g_chainstate.mapBlockIndex;
+BlockSeedHeightMap& mapBlockSeedHeight = g_chainstate.mapBlockSeedHeight;
 CChain& chainActive = g_chainstate.chainActive;
 CBlockIndex *pindexBestHeader = nullptr;
 CWaitableCriticalSection csBestBlock;
@@ -2880,6 +2882,10 @@ CBlockIndex* CChainState::AddToBlockIndex(const CBlockHeader& block)
     // to avoid miners withholding blocks but broadcasting headers, to get a
     // competitive advantage.
     pindexNew->nSequenceId = 0;
+    uint64_t height = block.nNonce;
+    if (crypto::is_a_seed_height(height)) {
+        mapBlockSeedHeight.insert(std::make_pair(height, pindexNew));
+    }
     BlockMap::iterator mi = mapBlockIndex.insert(std::make_pair(hash, pindexNew)).first;
     pindexNew->phashBlock = &((*mi).first);
     BlockMap::iterator miPrev = mapBlockIndex.find(block.hashPrevBlock);

src/validation.h

@@ -161,6 +161,8 @@ extern CBlockPolicyEstimator feeEstimator;
 extern CTxMemPool mempool;
 typedef std::unordered_map<uint256, CBlockIndex*, BlockHasher> BlockMap;
 extern BlockMap& mapBlockIndex;
+typedef std::map<uint64_t, CBlockIndex*> BlockSeedHeightMap;
+extern BlockSeedHeightMap& mapBlockSeedHeight;
 extern uint64_t nLastBlockTx;
 extern uint64_t nLastBlockWeight;
 extern const std::string strMessageMagic;