Removed unnecessary function

src/core/ExpressionToRegister.go

@@ -12,8 +12,6 @@ import (
 
 // ExpressionToRegister puts the result of an expression into the specified register.
 func (f *Function) ExpressionToRegister(node *expression.Expression, register cpu.Register) (types.Type, error) {
-	f.SaveRegister(register)
-
 	if node.IsFolded {
 		f.RegisterNumber(asm.MOVE, register, node.Value)
 		return types.Int, nil