Move CBlockIndex::GetBlockWork() to pow::GetProofIncrement(nBits)

src/main.h

@@ -14,6 +14,7 @@
 #include "coins.h"
 #include "core.h"
 #include "net.h"
+#include "pow.h"
 #include "script.h"
 #include "sync.h"
 #include "txmempool.h"
@@ -792,17 +793,7 @@ public:
 
     uint256 GetBlockWork() const
     {
-        uint256 bnTarget;
-        bool fNegative;
-        bool fOverflow;
-        bnTarget.SetCompact(nBits, &fNegative, &fOverflow);
-        if (fNegative || fOverflow || bnTarget == 0)
-            return 0;
-        // We need to compute 2**256 / (bnTarget+1), but we can't represent 2**256
-        // as it's too large for a uint256. However, as 2**256 is at least as large
-        // as bnTarget+1, it is equal to ((2**256 - bnTarget - 1) / (bnTarget+1)) + 1,
-        // or ~bnTarget / (nTarget+1) + 1.
-        return (~bnTarget / (bnTarget + 1)) + 1;
+        return GetProofIncrement(nBits);
     }
 
     enum { nMedianTimeSpan=11 };

src/pow.cpp

@@ -127,3 +127,18 @@ void UpdateTime(CBlockHeader* pblock, const CBlockIndex* pindexPrev)
     if (Params().AllowMinDifficultyBlocks())
         pblock->nBits = GetNextWorkRequired(pindexPrev, pblock);
 }
+
+uint256 GetProofIncrement(unsigned int nBits)
+{
+    uint256 bnTarget;
+    bool fNegative;
+    bool fOverflow;
+    bnTarget.SetCompact(nBits, &fNegative, &fOverflow);
+    if (fNegative || fOverflow || bnTarget == 0)
+        return 0;
+    // We need to compute 2**256 / (bnTarget+1), but we can't represent 2**256
+    // as it's too large for a uint256. However, as 2**256 is at least as large
+    // as bnTarget+1, it is equal to ((2**256 - bnTarget - 1) / (bnTarget+1)) + 1,
+    // or ~bnTarget / (nTarget+1) + 1.
+    return (~bnTarget / (bnTarget + 1)) + 1;
+}

src/pow.h

@@ -22,4 +22,6 @@ unsigned int ComputeMinWork(unsigned int nBase, int64_t nTime);
 
 void UpdateTime(CBlockHeader* block, const CBlockIndex* pindexPrev);
 
+uint256 GetProofIncrement(unsigned int nBits);
+
 #endif