consensus, core, tests: implement Metropolis EIP 649

core/vm/logger.go

@@ -128,18 +128,14 @@ func (l *StructLogger) CaptureState(env *EVM, pc uint64, op OpCode, gas, cost ui
 	}
 
 	// capture SSTORE opcodes and determine the changed value and store
-	// it in the local storage container. NOTE: we do not need to do any
-	// range checks here because that's already handler prior to calling
-	// this function.
-	switch op {
-	case SSTORE:
+	// it in the local storage container.
+	if op == SSTORE && stack.len() >= 2 {
 		var (
 			value   = common.BigToHash(stack.data[stack.len()-2])
 			address = common.BigToHash(stack.data[stack.len()-1])
 		)
 		l.changedValues[contract.Address()][address] = value
 	}
-
 	// copy a snapstot of the current memory state to a new buffer
 	var mem []byte
 	if !l.cfg.DisableMemory {