VirtualMachine: Add procedures

Author: adazem009

src/engine/virtualmachine.cpp

@@ -37,6 +37,7 @@ VirtualMachine::VirtualMachine(Target *target, Engine *engine) :
     for (int i = 0; i < MAX_REG_COUNT; i++)
         m_regs[i] = new Value();
     m_loops.reserve(256);
+    m_callTree.reserve(1024);
 }
 
 /*! Destroys the VirtualMachine object. */
@@ -47,6 +48,13 @@ VirtualMachine::~VirtualMachine()
     delete m_regs;
 }
 
+/*! Sets the list of procedures (custom blocks). */
+void VirtualMachine::setProcedures(const std::vector<unsigned int *> &procedures)
+{
+    m_proceduresVector = procedures;
+    m_procedures = m_proceduresVector.data();
+}
+
 /*! Sets the list of functions. */
 void VirtualMachine::setFunctions(const std::vector<BlockFunc> &functions)
 {
@@ -145,7 +153,8 @@ unsigned int *VirtualMachine::run(unsigned int *pos)
         &&do_str_at,
         &&do_str_length,
         &&do_str_contains,
-        &&do_exec
+        &&do_exec,
+        &&do_call_procedure
     };
     unsigned int *loopStart;
     unsigned int *loopEnd;
@@ -156,8 +165,14 @@ unsigned int *VirtualMachine::run(unsigned int *pos)
     if (m_regCount > 0) {
         std::cout << "warning: VM: " << m_regCount << " registers were leaked by the script; this is most likely a bug in the VM or in the compiler" << std::endl;
     }
-    m_atEnd = true;
-    return pos;
+    if (m_callTree.empty()) {
+        m_atEnd = true;
+        return pos;
+    } else {
+        pos = m_callTree.back();
+        m_callTree.pop_back();
+        DISPATCH();
+    }
 
 do_const:
     ADD_RET_VALUE(GET_NEXT_ARG());
@@ -576,4 +591,9 @@ do_list_get_item : {
 do_exec:
     FREE_REGS(m_functions[*++pos](this));
     DISPATCH();
+
+do_call_procedure:
+    m_callTree.push_back(++pos);
+    pos = m_procedures[*pos];
+    DISPATCH();
 }

src/engine/virtualmachine.h

@@ -68,7 +68,8 @@ enum Opcode
     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. */
+    OP_EXEC,          /*!< Calls the function with the index in the argument. */
+    OP_CALL_PROCEDURE /*! Calls the procedure (custom block) with the index in the argument. */
 };
 
 }
@@ -84,6 +85,7 @@ class LIBSCRATCHCPP_EXPORT VirtualMachine
         VirtualMachine(const VirtualMachine &) = delete;
         ~VirtualMachine();
 
+        void setProcedures(const std::vector<unsigned int *> &procedures);
         void setFunctions(const std::vector<BlockFunc> &functions);
         void setConstValues(const std::vector<Value> &values);
         void setVariables(const std::vector<Value *> &variables);
@@ -111,7 +113,7 @@ class LIBSCRATCHCPP_EXPORT VirtualMachine
         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, 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
+            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, 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, 1
         };
 
         typedef struct
@@ -128,6 +130,10 @@ class LIBSCRATCHCPP_EXPORT VirtualMachine
         Engine *m_engine = nullptr;
         bool m_atEnd = false;
         std::vector<Loop> m_loops;
+        std::vector<unsigned int *> m_callTree;
+
+        unsigned int **m_procedures = nullptr;
+        std::vector<unsigned int *> m_proceduresVector;
 
         BlockFunc *m_functions;
         std::vector<BlockFunc> m_functionsVector;