vm: drop ParamCount from Context

It's unused and it's useless.

pkg/core/interop/contract/call.go

@@ -113,7 +113,7 @@ func callExFromNative(ic *interop.Context, caller util.Uint160, cs *state.Contra
 	}
 
 	ic.VM.Invocations[cs.Hash]++
-	ic.VM.LoadScriptWithCallingHash(caller, cs.NEF.Script, cs.Hash, ic.VM.Context().GetCallFlags()&f, hasReturn, uint16(len(args)))
+	ic.VM.LoadScriptWithCallingHash(caller, cs.NEF.Script, cs.Hash, ic.VM.Context().GetCallFlags()&f, hasReturn)
 	ic.VM.Context().NEF = &cs.NEF
 	for e, i := ic.VM.Estack(), len(args)-1; i >= 0; i-- {
 		e.PushItem(args[i])

pkg/vm/context.go

@@ -48,8 +48,6 @@ type Context struct {
 	// Call flags this context was created with.
 	callFlag callflag.CallFlag
 
-	// ParamCount specifies number of parameters.
-	ParamCount int
 	// RetCount specifies number of return values.
 	RetCount int
 	// NEF represents NEF file for the current contract.
@@ -73,17 +71,16 @@ var errNoInstParam = errors.New("failed to read instruction parameter")
 
 // NewContext returns a new Context object.
 func NewContext(b []byte) *Context {
-	return NewContextWithParams(b, 0, -1, 0)
+	return NewContextWithParams(b, -1, 0)
 }
 
 // NewContextWithParams creates new Context objects using script, parameter count,
 // return value count and initial position in script.
-func NewContextWithParams(b []byte, pcount int, rvcount int, pos int) *Context {
+func NewContextWithParams(b []byte, rvcount int, pos int) *Context {
 	return &Context{
-		prog:       b,
+		prog:     b,
-		ParamCount: pcount,
+		RetCount: rvcount,
-		RetCount:   rvcount,
+		nextip:   pos,
-		nextip:     pos,
 	}
 }
 

pkg/vm/vm.go

@@ -279,7 +279,7 @@ func (v *VM) LoadScript(b []byte) {
 // LoadScriptWithFlags loads script and sets call flag to f.
 func (v *VM) LoadScriptWithFlags(b []byte, f callflag.CallFlag) {
 	v.checkInvocationStackSize()
-	ctx := NewContextWithParams(b, 0, -1, 0)
+	ctx := NewContextWithParams(b, -1, 0)
 	v.estack = newStack("evaluation", &v.refs)
 	ctx.estack = v.estack
 	initStack(&ctx.tryStack, "exception", nil)
@@ -297,13 +297,13 @@ func (v *VM) LoadScriptWithFlags(b []byte, f callflag.CallFlag) {
 // each other.
 func (v *VM) LoadScriptWithHash(b []byte, hash util.Uint160, f callflag.CallFlag) {
 	shash := v.GetCurrentScriptHash()
-	v.LoadScriptWithCallingHash(shash, b, hash, f, true, 0)
+	v.LoadScriptWithCallingHash(shash, b, hash, f, true)
 }
 
 // LoadScriptWithCallingHash is similar to LoadScriptWithHash but sets calling hash explicitly.
 // It should be used for calling from native contracts.
 func (v *VM) LoadScriptWithCallingHash(caller util.Uint160, b []byte, hash util.Uint160,
-	f callflag.CallFlag, hasReturn bool, paramCount uint16) {
+	f callflag.CallFlag, hasReturn bool) {
 	v.LoadScriptWithFlags(b, f)
 	ctx := v.Context()
 	ctx.scriptHash = hash
@@ -313,7 +313,6 @@ func (v *VM) LoadScriptWithCallingHash(caller util.Uint160, b []byte, hash util.
 	} else {
 		ctx.RetCount = 0
 	}
-	ctx.ParamCount = int(paramCount)
 }
 
 // Context returns the current executed context. Nil if there is no context,