Merge bitcoin/bitcoin#24956: Call CHECK_NONFATAL only once where needed

fab34d3 Call CHECK_NONFATAL only once where needed (MarcoFalke)

Pull request description:

  Now that `CHECK_NONFATAL` is the identity function starting with commit b1c5991, it can be called less often in places where it was called more than once on the same value.

ACKs for top commit:
  jonatack:
    Review ACK fab34d3

Tree-SHA512: ae221d7ee81f8d0be7ab21ce54d5d209e691df8a5c7f4a6f6db282453391904f87f533a2b7f85d6259827de8b85dacd9e0d9dbeecc4245a338247e0893ff3459

Author: MacroFake

src/rpc/blockchain.cpp

@@ -1199,24 +1199,23 @@ RPCHelpMan getblockchaininfo()
     LOCK(cs_main);
     CChainState& active_chainstate = chainman.ActiveChainstate();
 
-    const CBlockIndex* tip = CHECK_NONFATAL(active_chainstate.m_chain.Tip());
-    const int height = tip->nHeight;
+    const CBlockIndex& tip{*CHECK_NONFATAL(active_chainstate.m_chain.Tip())};
+    const int height{tip.nHeight};
     UniValue obj(UniValue::VOBJ);
     obj.pushKV("chain", Params().NetworkIDString());
     obj.pushKV("blocks", height);
     obj.pushKV("headers", chainman.m_best_header ? chainman.m_best_header->nHeight : -1);
-    obj.pushKV("bestblockhash", tip->GetBlockHash().GetHex());
-    obj.pushKV("difficulty", (double)GetDifficulty(tip));
-    obj.pushKV("time", (int64_t)tip->nTime);
-    obj.pushKV("mediantime", (int64_t)tip->GetMedianTimePast());
-    obj.pushKV("verificationprogress", GuessVerificationProgress(Params().TxData(), tip));
+    obj.pushKV("bestblockhash", tip.GetBlockHash().GetHex());
+    obj.pushKV("difficulty", GetDifficulty(&tip));
+    obj.pushKV("time", int64_t{tip.nTime});
+    obj.pushKV("mediantime", tip.GetMedianTimePast());
+    obj.pushKV("verificationprogress", GuessVerificationProgress(Params().TxData(), &tip));
     obj.pushKV("initialblockdownload", active_chainstate.IsInitialBlockDownload());
-    obj.pushKV("chainwork", tip->nChainWork.GetHex());
+    obj.pushKV("chainwork", tip.nChainWork.GetHex());
     obj.pushKV("size_on_disk", chainman.m_blockman.CalculateCurrentUsage());
     obj.pushKV("pruned", node::fPruneMode);
     if (node::fPruneMode) {
-        const CBlockIndex* block = CHECK_NONFATAL(tip);
-        obj.pushKV("pruneheight", node::GetFirstStoredBlock(block)->nHeight);
+        obj.pushKV("pruneheight", node::GetFirstStoredBlock(&tip)->nHeight);
 
         // if 0, execution bypasses the whole if block.
         bool automatic_pruning{args.GetIntArg("-prune", 0) != 1};
@@ -1228,7 +1227,7 @@ RPCHelpMan getblockchaininfo()
 
     if (IsDeprecatedRPCEnabled("softforks")) {
         const Consensus::Params& consensusParams = Params().GetConsensus();
-        obj.pushKV("softforks", DeploymentInfo(tip, consensusParams));
+        obj.pushKV("softforks", DeploymentInfo(&tip, consensusParams));
     }
 
     obj.pushKV("warnings", GetWarnings(false).original);