From 1863023e277c07ca08a8f2d4c2977daf486e7f40 Mon Sep 17 00:00:00 2001
From: Evgeniy Stratonikov <evgeniy@nspcc.ru>
Date: Thu, 8 Jul 2021 14:07:02 +0300
Subject: [PATCH] vm: copy argument in unary opcodes, fix #2051

We already do this in binary opcodes, let's be consistent.

This fixes state difference at height 275663
for tx 3c498317684d63849b03e4c58ad57ce4b19bb206b7b01bcc64233de3b3e207f4

Signed-off-by: Evgeniy Stratonikov <evgeniy@nspcc.ru>
---
 pkg/vm/vm.go      |  6 +++---
 pkg/vm/vm_test.go | 12 ++++++++++++
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/pkg/vm/vm.go b/pkg/vm/vm.go
index d2eb26780..12014aeaa 100644
--- a/pkg/vm/vm.go
+++ b/pkg/vm/vm.go
@@ -831,7 +831,7 @@ func (v *VM) execute(ctx *Context, op opcode.Opcode, parameter []byte) (err erro
 		// inplace
 		e := v.estack.Peek(0)
 		i := e.BigInt()
-		e.value = stackitem.Make(i.Not(i))
+		e.value = stackitem.Make(new(big.Int).Not(i))
 
 	case opcode.AND:
 		b := v.estack.Pop().BigInt()
@@ -866,11 +866,11 @@ func (v *VM) execute(ctx *Context, op opcode.Opcode, parameter []byte) (err erro
 
 	case opcode.ABS:
 		x := v.estack.Pop().BigInt()
-		v.estack.PushVal(x.Abs(x))
+		v.estack.PushVal(new(big.Int).Abs(x))
 
 	case opcode.NEGATE:
 		x := v.estack.Pop().BigInt()
-		v.estack.PushVal(x.Neg(x))
+		v.estack.PushVal(new(big.Int).Neg(x))
 
 	case opcode.INC:
 		x := v.estack.Pop().BigInt()
diff --git a/pkg/vm/vm_test.go b/pkg/vm/vm_test.go
index c70f9a282..91870e236 100644
--- a/pkg/vm/vm_test.go
+++ b/pkg/vm/vm_test.go
@@ -2050,6 +2050,18 @@ func TestDupInt(t *testing.T) {
 	assert.Equal(t, int64(-1), vm.estack.Pop().BigInt().Int64())
 }
 
+func TestNegateCopy(t *testing.T) {
+	prog := makeProgram(opcode.NEGATE)
+	v := load(prog)
+	bi := stackitem.Make(-1)
+	v.estack.PushVal(bi)
+	v.estack.PushVal(bi)
+	runVM(t, v)
+	assert.Equal(t, 2, v.estack.Len())
+	assert.Equal(t, int64(1), v.estack.Pop().BigInt().Int64())
+	assert.Equal(t, int64(-1), v.estack.Pop().BigInt().Int64())
+}
+
 func TestDupByteArray(t *testing.T) {
 	prog := makeProgram(opcode.PUSHDATA1, 2, 1, 0,
 		opcode.DUP,