VirtualMachine: Add string operators

Author: adazem009

src/engine/virtualmachine.cpp

@@ -127,6 +127,10 @@ unsigned int *VirtualMachine::run(unsigned int *pos)
         &&do_list_index_of,
         &&do_list_length,
         &&do_list_contains,
+        &&do_str_concat,
+        &&do_str_at,
+        &&do_str_length,
+        &&do_str_contains,
         &&do_exec
     };
     unsigned int *loopStart;
@@ -417,6 +421,25 @@ do_list_get_item : {
     REPLACE_RET_VALUE(m_lists[*++pos]->contains(*READ_LAST_REG()), 1);
     DISPATCH();
 
+do_str_concat:
+    REPLACE_RET_VALUE(READ_REG(0, 2)->toString() + READ_REG(1, 2)->toString(), 2);
+    FREE_REGS(1);
+    DISPATCH();
+
+do_str_at:
+    REPLACE_RET_VALUE(READ_REG(0, 2)->toUtf16()[READ_REG(1, 2)->toLong()], 2);
+    FREE_REGS(1);
+    DISPATCH();
+
+do_str_length:
+    REPLACE_RET_VALUE(static_cast<long>(READ_REG(0, 1)->toUtf16().size()), 1);
+    DISPATCH();
+
+do_str_contains:
+    REPLACE_RET_VALUE(READ_REG(0, 2)->toUtf16().find(READ_REG(1, 2)->toUtf16()) != std::u16string::npos, 2);
+    FREE_REGS(1);
+    DISPATCH();
+
 do_exec:
     FREE_REGS(m_functions[*++pos](this));
     DISPATCH();

src/engine/virtualmachine.h

@@ -53,6 +53,10 @@ enum Opcode
     OP_LIST_INDEX_OF, /*!< Stores the index of the value from the last register in the last register (of the list with the index in the argument). */
     OP_LIST_LENGTH,   /*!< Stores the length of the list with the index in the argument, in the last register. */
     OP_LIST_CONTAINS, /*!< Stores true in the last register if the list with the index in the argument contains the value from the last register. */
+    OP_STR_CONCAT,    /*!< Concatenates the strings stored in the last 2 registers and stores the result in the last register, deleting the input registers. */
+    OP_STR_AT,        /*! Stores the character at index in the last register of the string in the second last register, in the last register. */
+    OP_STR_LENGTH,    /*! Stores the length of the string in the last register, in the last register. */
+    OP_STR_CONTAINS,  /*! Stores true in the last register if the string stored in the second last register contains the substring in the last register. */
     OP_EXEC           /*!< Calls the function with the index in the argument. */
 };
 
@@ -95,7 +99,7 @@ class LIBSCRATCHCPP_EXPORT VirtualMachine
     private:
         unsigned int *run(unsigned int *pos);
 
-        static inline const unsigned int instruction_arg_count[] = { 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 };
+        static inline const unsigned int instruction_arg_count[] = { 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1 };
 
         unsigned int *m_bytecode;
         std::vector<unsigned int> m_bytecodeVector;