Generic TransactionSignatureCreator works with both CTransaction and CMutableTransaction

Templated version so that no copying of CMutableTransaction into a CTransaction is
necessary. This speeds up the test case transaction_tests/test_big_witness_transaction
from 7.9 seconds to 3.1 seconds on my machine.

1 files changed, 11 insertions, 14 deletions

diff --git a/src/script/interpreter.h b/src/script/interpreter.h
index 2800473a68..2d21aa81df 100644
--- a/src/script/interpreter.h
+++ b/src/script/interpreter.h
@@ -124,7 +124,8 @@ struct PrecomputedTransactionData
     uint256 hashPrevouts, hashSequence, hashOutputs;
     bool ready = false;
 
-    explicit PrecomputedTransactionData(const CTransaction& tx);
+    template <class T>
+    explicit PrecomputedTransactionData(const T& tx);
 };
 
 enum class SigVersion
@@ -137,7 +138,8 @@ enum class SigVersion
 static constexpr size_t WITNESS_V0_SCRIPTHASH_SIZE = 32;
 static constexpr size_t WITNESS_V0_KEYHASH_SIZE = 20;
 
-uint256 SignatureHash(const CScript &scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType, const CAmount& amount, SigVersion sigversion, const PrecomputedTransactionData* cache = nullptr);
+template <class T>
+uint256 SignatureHash(const CScript& scriptCode, const T& txTo, unsigned int nIn, int nHashType, const CAmount& amount, SigVersion sigversion, const PrecomputedTransactionData* cache = nullptr);
 
 class BaseSignatureChecker
 {
@@ -160,10 +162,11 @@ public:
     virtual ~BaseSignatureChecker() {}
 };
 
-class TransactionSignatureChecker : public BaseSignatureChecker
+template <class T>
+class GenericTransactionSignatureChecker : public BaseSignatureChecker
 {
 private:
-    const CTransaction* txTo;
+    const T* txTo;
     unsigned int nIn;
     const CAmount amount;
     const PrecomputedTransactionData* txdata;
@@ -172,21 +175,15 @@ protected:
     virtual bool VerifySignature(const std::vector<unsigned char>& vchSig, const CPubKey& vchPubKey, const uint256& sighash) const;
 
 public:
-    TransactionSignatureChecker(const CTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn) : txTo(txToIn), nIn(nInIn), amount(amountIn), txdata(nullptr) {}
-    TransactionSignatureChecker(const CTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, const PrecomputedTransactionData& txdataIn) : txTo(txToIn), nIn(nInIn), amount(amountIn), txdata(&txdataIn) {}
+    GenericTransactionSignatureChecker(const T* txToIn, unsigned int nInIn, const CAmount& amountIn) : txTo(txToIn), nIn(nInIn), amount(amountIn), txdata(nullptr) {}
+    GenericTransactionSignatureChecker(const T* txToIn, unsigned int nInIn, const CAmount& amountIn, const PrecomputedTransactionData& txdataIn) : txTo(txToIn), nIn(nInIn), amount(amountIn), txdata(&txdataIn) {}
     bool CheckSig(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override;
     bool CheckLockTime(const CScriptNum& nLockTime) const override;
     bool CheckSequence(const CScriptNum& nSequence) const override;
 };
 
-class MutableTransactionSignatureChecker : public TransactionSignatureChecker
-{
-private:
-    const CTransaction txTo;
-
-public:
-    MutableTransactionSignatureChecker(const CMutableTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn) : TransactionSignatureChecker(&txTo, nInIn, amountIn), txTo(*txToIn) {}
-};
+using TransactionSignatureChecker = GenericTransactionSignatureChecker<CTransaction>;
+using MutableTransactionSignatureChecker = GenericTransactionSignatureChecker<CMutableTransaction>;
 
 bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptError* error = nullptr);
 bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const CScriptWitness* witness, unsigned int flags, const BaseSignatureChecker& checker, ScriptError* serror = nullptr);