neo-go/pkg/vm/vm_ops_flow.go
decentralisedkev c1b6738bdb
VM: Add basic vm (#166)
* VM:Add abstract stack item

* VM: Add stackItems; Array, Boolean, Int and ByteArray

* VM: Add tests for stack item

* VM: first pass at Random Access Stack object

* VM: Add Sub, Mul, Mod LSH, RSH

* VM: moved test helper functions into separate file

* VM: removed helper functions from stack_test.go

* Add conversions for bytearray and Int stack items

* Add instructions file for vm

* - Add guide to stack readme
- Add testReadInt64

* Add Builder

* Refactor Int, Boolean, ByteArray conversion

* Add Context stack Item

* Add Invocation stack - convenience RAS

* rename testhelper to test_helper

* Move opcode file

* - Add `Add` OpCode
- Add Opcode Function map

* - Add test for math `Add` opcode
- basic opcode execution

* Add popTwoIntegers convenience func

* Add `SUB` Opcode

* Export Context Read methods
- Return errors where failable

* - Add `Op` to handleOP func signature
- Add PushNBytes OPcode

* remove error on NewBoolean
- Expose underlying with Getter on Boolean StackItem
- Add Equals method for ByteArray

* Make Next() method on Context failable, refactor peekContext and Peek

* Add ExecuteOp, Step and Run methods on the VM

* Add Equal Opcode

* Add THROWIFNOT Opcode

* Add RET Opcode

* Refactor PushNBytes Opcode

* refactor Add, Sub to return VMSTATE
add popTwoByteArrays helper function

* Add basic tests for vm

* clarify vm states

* Add astack

* [VM]

Pass ResultStack to the opcode handlers

* [VM]

refactor handlers to have rstack as argument

* [Stack]

- Change RemoveCurrentContext for PopCurrentContext
- Add CopTo method to stack

* [VM]

Add Result stack Len check in simple run test

* [VM] fix typo

* [Peer/Stall]

Change seconds to milliseconds in test
2019-03-18 21:40:21 +00:00

27 lines
696 B
Go

package vm
import (
"github.com/CityOfZion/neo-go/pkg/vm/stack"
)
// Flow control
// RET Returns from the current context
// Returns HALT if there are nomore context's to run
func RET(op stack.Instruction, ctx *stack.Context, istack *stack.Invocation, rstack *stack.RandomAccess) (Vmstate, error) {
// Pop current context from the Inovation stack
ctx, err := istack.PopCurrentContext()
if err != nil {
return FAULT, err
}
// If this was the last context, then we copy over the evaluation stack to the resultstack
// As the program is about to terminate, once we remove the context
if istack.Len() == 0 {
err = ctx.Estack.CopyTo(rstack)
return HALT, err
}
return NONE, nil
}