core/vm: fix benchmark overflow + prep for precompile repricings (eth…

…ereum#21530)

* core/vm/testdata: add gascost expectations to testcases

* core/vm: verify expected gas in tests for precompiles

* core/vm: fix overflow flaw in gas/s calculation

core/vm/contracts_test.go

@@ -30,6 +30,7 @@ import (
 // precompiledTest defines the input/output pairs for precompiled contract tests.
 type precompiledTest struct {
 	Input, Expected string
+	Gas             uint64
 	Name            string
 	NoBenchmark     bool // Benchmark primarily the worst-cases
 }
@@ -78,6 +79,9 @@ func testPrecompiled(addr string, test precompiledTest, t *testing.T) {
 		} else if common.Bytes2Hex(res) != test.Expected {
 			t.Errorf("Expected %v, got %v", test.Expected, common.Bytes2Hex(res))
 		}
+		if expGas := test.Gas; expGas != gas {
+			t.Errorf("%v: gas wrong, expected %d, got %d", test.Name, expGas, gas)
+		}
 		// Verify that the precompile did not touch the input buffer
 		exp := common.Hex2Bytes(test.Input)
 		if !bytes.Equal(in, exp) {
@@ -137,20 +141,22 @@ func benchmarkPrecompiled(addr string, test precompiledTest, bench *testing.B) {
 
 	bench.Run(fmt.Sprintf("%s-Gas=%d", test.Name, reqGas), func(bench *testing.B) {
 		bench.ReportAllocs()
-		start := time.Now().Nanosecond()
+		start := time.Now()
 		bench.ResetTimer()
 		for i := 0; i < bench.N; i++ {
 			copy(data, in)
 			res, _, err = RunPrecompiledContract(p, data, reqGas)
 		}
 		bench.StopTimer()
-		elapsed := float64(time.Now().Nanosecond() - start)
+		elapsed := uint64(time.Since(start))
 		if elapsed < 1 {
 			elapsed = 1
 		}
 		gasUsed := reqGas * uint64(bench.N)
 		bench.ReportMetric(float64(reqGas), "gas/op")
-		bench.ReportMetric(float64(gasUsed*1000)/elapsed, "mgas/s")
+		// Keep it as uint64, multiply 100 to get two digit float later
+		mgasps := (100 * 1000 * gasUsed) / elapsed
+		bench.ReportMetric(float64(mgasps)/100, "mgas/s")
 		//Check if it is correct
 		if err != nil {
 			bench.Error(err)

core/vm/testdata/precompiles/blake2F.json

@@ -3,30 +3,35 @@
     "Input": "0000000048c9bdf267e6096a3ba7ca8485ae67bb2bf894fe72f36e3cf1361d5f3af54fa5d182e6ad7f520e511f6c3e2b8c68059b6bbd41fbabd9831f79217e1319cde05b61626300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000300000000000000000000000000000001",
     "Expected": "08c9bcf367e6096a3ba7ca8485ae67bb2bf894fe72f36e3cf1361d5f3af54fa5d282e6ad7f520e511f6c3e2b8c68059b9442be0454267ce079217e1319cde05b",
     "Name": "vector 4",
+    "Gas": 0,
     "NoBenchmark": false
   },
   {
     "Input": "0000000c48c9bdf267e6096a3ba7ca8485ae67bb2bf894fe72f36e3cf1361d5f3af54fa5d182e6ad7f520e511f6c3e2b8c68059b6bbd41fbabd9831f79217e1319cde05b61626300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000300000000000000000000000000000001",
     "Expected": "ba80a53f981c4d0d6a2797b69f12f6e94c212f14685ac4b74b12bb6fdbffa2d17d87c5392aab792dc252d5de4533cc9518d38aa8dbf1925ab92386edd4009923",
     "Name": "vector 5",
+    "Gas": 12,
     "NoBenchmark": false
   },
   {
     "Input": "0000000c48c9bdf267e6096a3ba7ca8485ae67bb2bf894fe72f36e3cf1361d5f3af54fa5d182e6ad7f520e511f6c3e2b8c68059b6bbd41fbabd9831f79217e1319cde05b61626300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000300000000000000000000000000000000",
     "Expected": "75ab69d3190a562c51aef8d88f1c2775876944407270c42c9844252c26d2875298743e7f6d5ea2f2d3e8d226039cd31b4e426ac4f2d3d666a610c2116fde4735",
     "Name": "vector 6",
+    "Gas": 12,
     "NoBenchmark": false
   },
   {
     "Input": "0000000148c9bdf267e6096a3ba7ca8485ae67bb2bf894fe72f36e3cf1361d5f3af54fa5d182e6ad7f520e511f6c3e2b8c68059b6bbd41fbabd9831f79217e1319cde05b61626300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000300000000000000000000000000000001",
     "Expected": "b63a380cb2897d521994a85234ee2c181b5f844d2c624c002677e9703449d2fba551b3a8333bcdf5f2f7e08993d53923de3d64fcc68c034e717b9293fed7a421",
     "Name": "vector 7",
+    "Gas": 1,
     "NoBenchmark": false
   },
   {
     "Input": "007A120048c9bdf267e6096a3ba7ca8485ae67bb2bf894fe72f36e3cf1361d5f3af54fa5d182e6ad7f520e511f6c3e2b8c68059b6bbd41fbabd9831f79217e1319cde05b61626300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000300000000000000000000000000000001",
     "Expected": "6d2ce9e534d50e18ff866ae92d70cceba79bbcd14c63819fe48752c8aca87a4bb7dcc230d22a4047f0486cfcfb50a17b24b2899eb8fca370f22240adb5170189",
     "Name": "vector 8",
+    "Gas": 8000000,
     "NoBenchmark": false
   }
 ]