Introduce `zcsamplejoinsplit` for creating a raw joinsplit description, and use it to construct the joinsplit for the performance tests that verify joinsplits.

qa/zcash/performance-measurements.sh

@@ -52,6 +52,17 @@ function zcashd_valgrind_stop {
     cat valgrind.out
 }
 
+# Precomputation
+case "$1" in
+    *)
+        case "$2" in
+            verifyjoinsplit)
+                zcashd_start
+                RAWJOINSPLIT=$(zcash_rpc zcsamplejoinsplit)
+                zcashd_stop
+        esac
+esac
+
 case "$1" in
     time)
         zcashd_start
@@ -66,7 +77,7 @@ case "$1" in
                 zcash_rpc zcbenchmark createjoinsplit 10
                 ;;
             verifyjoinsplit)
-                zcash_rpc zcbenchmark verifyjoinsplit 1000
+                zcash_rpc zcbenchmark verifyjoinsplit 1000 "$RAWJOINSPLIT"
                 ;;
             solveequihash)
                 zcash_rpc zcbenchmark solveequihash 10
@@ -97,7 +108,7 @@ case "$1" in
                 zcash_rpc zcbenchmark createjoinsplit 1
                 ;;
             verifyjoinsplit)
-                zcash_rpc zcbenchmark verifyjoinsplit 1
+                zcash_rpc zcbenchmark verifyjoinsplit 1 "$RAWJOINSPLIT"
                 ;;
             solveequihash)
                 zcash_rpc zcbenchmark solveequihash 1
@@ -126,7 +137,7 @@ case "$1" in
                 zcash_rpc zcbenchmark createjoinsplit 1
                 ;;
             verifyjoinsplit)
-                zcash_rpc zcbenchmark verifyjoinsplit 1
+                zcash_rpc zcbenchmark verifyjoinsplit 1 "$RAWJOINSPLIT"
                 ;;
             solveequihash)
                 zcash_rpc zcbenchmark solveequihash 1

src/rpcserver.cpp

@@ -380,7 +380,8 @@ static const CRPCCommand vRPCCommands[] =
     { "wallet",             "zcbenchmark",            &zc_benchmark,           true  },
     { "wallet",             "zcrawkeygen",            &zc_raw_keygen,          true  },
     { "wallet",             "zcrawjoinsplit",         &zc_raw_joinsplit,       true  },
-    { "wallet",             "zcrawreceive",           &zc_raw_receive,         true  }
+    { "wallet",             "zcrawreceive",           &zc_raw_receive,         true  },
+    { "wallet",             "zcsamplejoinsplit",      &zc_sample_joinsplit,    true  }
 #endif // ENABLE_WALLET
 };
 

src/rpcserver.h

@@ -212,6 +212,7 @@ extern json_spirit::Value zc_benchmark(const json_spirit::Array& params, bool fH
 extern json_spirit::Value zc_raw_keygen(const json_spirit::Array& params, bool fHelp);
 extern json_spirit::Value zc_raw_joinsplit(const json_spirit::Array& params, bool fHelp);
 extern json_spirit::Value zc_raw_receive(const json_spirit::Array& params, bool fHelp);
+extern json_spirit::Value zc_sample_joinsplit(const json_spirit::Array& params, bool fHelp);
 
 extern json_spirit::Value getrawtransaction(const json_spirit::Array& params, bool fHelp); // in rcprawtransaction.cpp
 extern json_spirit::Value listunspent(const json_spirit::Array& params, bool fHelp);

src/wallet/rpcwallet.cpp

@@ -2351,6 +2351,34 @@ Value listunspent(const Array& params, bool fHelp)
     return results;
 }
 
+Value zc_sample_joinsplit(const json_spirit::Array& params, bool fHelp)
+{
+    if (fHelp) {
+        throw runtime_error(
+            "zcsamplejoinsplit\n"
+            "\n"
+            "Perform a joinsplit and return the JSDescription.\n"
+            );
+    }
+
+    LOCK(cs_main);
+
+    uint256 pubKeyHash;
+    uint256 anchor = ZCIncrementalMerkleTree().root();
+    JSDescription samplejoinsplit(*pzcashParams,
+                                  pubKeyHash,
+                                  anchor,
+                                  {JSInput(), JSInput()},
+                                  {JSOutput(), JSOutput()},
+                                  0,
+                                  0);
+
+    CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
+    ss << samplejoinsplit;
+
+    return HexStr(ss.begin(), ss.end());
+}
+
 Value zc_benchmark(const json_spirit::Array& params, bool fHelp)
 {
     if (!EnsureWalletIsAvailable(fHelp)) {
@@ -2393,18 +2421,11 @@ Value zc_benchmark(const json_spirit::Array& params, bool fHelp)
         pzcashParams->loadProvingKey();
     }
 
-    JSDescription* samplejoinsplit = NULL;
+    JSDescription samplejoinsplit;
 
     if (benchmarktype == "verifyjoinsplit") {
-        uint256 pubKeyHash;
+        CDataStream ss(ParseHexV(params[2].get_str(), "js"), SER_NETWORK, PROTOCOL_VERSION);
-        uint256 anchor = ZCIncrementalMerkleTree().root();
+        ss >> samplejoinsplit;
-        samplejoinsplit = new JSDescription(*pzcashParams,
-                                            pubKeyHash,
-                                            anchor,
-                                            {JSInput(), JSInput()},
-                                            {JSOutput(), JSOutput()},
-                                            0,
-                                            0);
     }
 
     for (int i = 0; i < samplecount; i++) {
@@ -2415,7 +2436,7 @@ Value zc_benchmark(const json_spirit::Array& params, bool fHelp)
         } else if (benchmarktype == "createjoinsplit") {
             sample_times.push_back(benchmark_create_joinsplit());
         } else if (benchmarktype == "verifyjoinsplit") {
-            sample_times.push_back(benchmark_verify_joinsplit(*samplejoinsplit));
+            sample_times.push_back(benchmark_verify_joinsplit(samplejoinsplit));
         } else if (benchmarktype == "solveequihash") {
             sample_times.push_back(benchmark_solve_equihash());
         } else if (benchmarktype == "verifyequihash") {
@@ -2423,13 +2444,10 @@ Value zc_benchmark(const json_spirit::Array& params, bool fHelp)
         } else if (benchmarktype == "validatelargetx") {
             sample_times.push_back(benchmark_large_tx());
         } else {
-            delete samplejoinsplit;
             throw JSONRPCError(RPC_TYPE_ERROR, "Invalid benchmarktype");
         }
     }
 
-    delete samplejoinsplit;
-
     Array results;
     for (int i = 0; i < samplecount; i++) {
         Object result;