[WIP] add ResetVM()

2 files changed, 16 insertions, 3 deletions

diff --git a/core/vm/dvm/dvm.go b/core/vm/dvm/dvm.go
index c4812e637..ac6deedd5 100644
--- a/core/vm/dvm/dvm.go
+++ b/core/vm/dvm/dvm.go
@@ -474,8 +474,10 @@ func (dvm *DVM) run(contract *vm.Contract, input []byte, ro bool) ([]byte, error
 		wavm.RecoverPanic = true
 		dvm.vmCache[contract.CodeHash] = wavm
 	} else {
-		// reset memory if cache hit
-		copy(wavm.Memory(), module.LinearMemoryIndexSpace[0])
+		err := wavm.ResetVM()
+		if err != nil {
+			return nil, fmt.Errorf("could not reset the vm: %v", err)
+		}
 	}
 
 	dvm.vm = wavm
diff --git a/vendor/github.com/go-interpreter/wagon/exec/vm.go b/vendor/github.com/go-interpreter/wagon/exec/vm.go
index 7074d8e3a..369c7814b 100644
--- a/vendor/github.com/go-interpreter/wagon/exec/vm.go
+++ b/vendor/github.com/go-interpreter/wagon/exec/vm.go
@@ -160,6 +160,18 @@ func NewVM(module *wasm.Module) (*VM, error) {
 	return &vm, nil
 }
 
+func (vm *VM) ResetVM() error {
+	vm.abort = false
+	if vm.module.Memory != nil && len(vm.module.Memory.Entries) != 0 {
+		if len(vm.module.Memory.Entries) > 1 {
+			return ErrMultipleLinearMemories
+		}
+		vm.memory = make([]byte, uint(vm.module.Memory.Entries[0].Limits.Initial)*wasmPageSize)
+		copy(vm.memory, vm.module.LinearMemoryIndexSpace[0])
+	}
+	return nil
+}
+
 // Memory returns the linear memory space for the VM.
 func (vm *VM) Memory() []byte {
 	return vm.memory
@@ -296,7 +308,6 @@ func (vm *VM) ExecCode(fnIndex int64, args ...uint64) (rtrn interface{}, err err
 	vm.ctx.pc = 0
 	vm.ctx.code = compiled.code
 	vm.ctx.curFunc = fnIndex
-	vm.abort = false
 
 	for i, arg := range args {
 		vm.ctx.locals[i] = arg