Refactored rx-slow-hash.c

- Straight-forward call interface: `void rx_slow_hash(const char *seedhash, const void *data, size_t length, char *result_hash)`
- Consensus chain seed hash is now updated by calling `rx_set_main_seedhash` whenever a block is added/removed or a reorg happens
- `rx_slow_hash` will compute correct hash no matter if `rx_set_main_seedhash` was called or not (the only difference is performance)
- New environment variable `MONERO_RANDOMX_FULL_MEM` to force use the full dataset for PoW verification (faster block verification)
- When dataset is used for PoW verification, dataset updates don't stall other threads (verification is done in light mode then)
- When mining is running, PoW checks now also use dataset for faster verification

src/cryptonote_basic/miner.cpp

@@ -82,6 +82,7 @@
 using namespace epee;
 
 #include "miner.h"
+#include "crypto/hash.h"
 
 
 extern "C" void slow_hash_allocate_state();
@@ -436,7 +437,6 @@ namespace cryptonote
   {
     m_stop = true;
   }
-  extern "C" void rx_stop_mining(void);
   //-----------------------------------------------------------------------------------------------------
   bool miner::stop()
   {
@@ -469,7 +469,6 @@ namespace cryptonote
     MINFO("Mining has been stopped, " << m_threads.size() << " finished" );
     m_threads.clear();
     m_threads_autodetect.clear();
-    rx_stop_mining();
     return true;
   }
   //-----------------------------------------------------------------------------------------------------
@@ -524,6 +523,8 @@ namespace cryptonote
   bool miner::worker_thread()
   {
     const uint32_t th_local_index = m_thread_index++; // atomically increment, getting value before increment
+    crypto::rx_set_miner_thread(th_local_index, tools::get_max_concurrency());
+
     MLOG_SET_THREAD_NAME(std::string("[miner ") + std::to_string(th_local_index) + "]");
     MGINFO("Miner thread was started ["<< th_local_index << "]");
     uint32_t nonce = m_starter_nonce + th_local_index;