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adazem009adazem009
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Add VirtualMachine class
1 parent f936e4f commit 89b7bbd

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4 files changed

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‎src/engine/CMakeLists.txt‎

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Original file line numberDiff line numberDiff line change
@@ -2,10 +2,12 @@ target_sources(scratchcpp
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PRIVATE
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engine.cpp
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blockargs.cpp
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virtualmachine.cpp
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PUBLIC
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engine.h
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global.h
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blockargs.h
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virtualmachine.h
911
iblocksection.h
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iextension.h
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)

‎src/engine/global.h‎

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@@ -10,13 +10,22 @@
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namespace libscratchcpp
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{
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class LIBSCRATCHCPP_EXPORT VirtualMachine;
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/*!
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* \typedef BlockImpl
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*
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* BlockImpl is a function pointer for block implementation functions.
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*/
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using BlockImpl = Value (*)(const BlockArgs &);
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/*!
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* \typedef BlockFunc
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*
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* BlockFunc is a function pointer for block implementation functions.
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*/
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using BlockFunc = unsigned int (*)(VirtualMachine *vm);
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/*! Generates a random number in the given interval like the random.randint() function in Python. */
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template<typename T>
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inline T randint(T start, T end)

‎src/engine/virtualmachine.cpp‎

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// SPDX-License-Identifier: Apache-2.0
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#include "virtualmachine.h"
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#define DISPATCH() goto *dispatch_table[*++pos]
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#define FREE_REGS(count) m_regCount -= count
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#define ADD_RET_VALUE(value) *m_regs[m_regCount++] = value
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#define REPLACE_RET_VALUE(value, offset) *m_regs[m_regCount - offset] = value
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#define GET_NEXT_ARG() m_constValues[*++pos]
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#define READ_REG(index, count) m_regs[m_regCount - count + index]
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#define READ_LAST_REG() m_regs[m_regCount - 1]
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#define FIX_LIST_INDEX(index, listSize) \
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if ((listSize == 0) || (index < 1) || (index > listSize)) \
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index = 0
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using namespace libscratchcpp;
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using namespace vm;
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/*! Constructs VirtualMachine. */
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VirtualMachine::VirtualMachine()
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{
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m_regs = new Value *[1024];
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for (int i = 0; i < 1024; i++)
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m_regs[i] = new Value();
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}
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/*! Destroys the VirtualMachine object. */
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VirtualMachine::~VirtualMachine()
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{
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for (int i = 0; i < 1024; i++)
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delete m_regs[i];
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delete m_regs;
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}
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/*! Sets the list of functions. */
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void VirtualMachine::setFunctions(const std::vector<BlockFunc> &functions)
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{
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m_functionsVector = functions;
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m_functions = m_functionsVector.data();
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}
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/*! Sets the list of constant values. */
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void VirtualMachine::setConstValues(const std::vector<Value> &values)
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{
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m_constValuesVector = values;
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m_constValues = m_constValuesVector.data();
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}
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/*! Sets the bytecode of the script. */
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void VirtualMachine::setBytecode(const std::vector<unsigned int> &code)
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{
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m_bytecodeVector = code;
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m_bytecode = &m_bytecodeVector[0];
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}
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/*! Runs the script. */
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unsigned int *VirtualMachine::run(RunningScript *script)
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{
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return run(m_bytecode, script);
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}
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unsigned int *VirtualMachine::run(unsigned int *pos, RunningScript *script)
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{
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static const void *dispatch_table[] = {
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nullptr, &&do_halt, &&do_const, &&do_null, &&do_if, &&do_else, &&do_endif, &&do_repeat_loop, &&do_until_loop, &&do_begin_until_loop,
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&&do_loop_end, &&do_print, &&do_add, &&do_subtract, &&do_multiply, &&do_divide, &&do_random, &&do_greater_than, &&do_less_than, &&do_equals,
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&&do_and, &&do_or, &&do_not, &&do_set_var, &&do_change_var, &&do_read_var, &&do_read_list, &&do_list_append, &&do_list_del, &&do_list_del_all,
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&&do_list_insert, &&do_list_replace, &&do_list_get_item, &&do_list_index_of, &&do_list_length, &&do_list_contains, &&do_exec
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};
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unsigned int *loopStart;
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unsigned int *loopEnd;
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size_t loopCount;
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DISPATCH();
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do_halt:
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return pos;
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do_const:
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ADD_RET_VALUE(GET_NEXT_ARG());
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DISPATCH();
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do_null:
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ADD_RET_VALUE(Value());
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DISPATCH();
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do_if:
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if (!READ_LAST_REG()->toBool()) {
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while (*pos != OP_ELSE && *pos != OP_ENDIF && *pos != OP_HALT)
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pos += instruction_arg_count[*pos++];
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}
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FREE_REGS(1);
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DISPATCH();
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do_else:
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while (*pos != OP_ENDIF && *pos != OP_HALT)
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pos += instruction_arg_count[*pos++];
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do_endif:
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DISPATCH();
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do_repeat_loop:
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FREE_REGS(1);
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loopCount = READ_LAST_REG()->toLong();
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if (loopCount <= 0) {
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loopEnd = pos;
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while (*loopEnd != OP_LOOP_END && *loopEnd != OP_HALT)
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loopEnd += instruction_arg_count[*loopEnd++];
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} else {
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for (size_t i = 0; i < loopCount; i++)
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loopEnd = run(pos, script);
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}
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pos = loopEnd;
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DISPATCH();
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do_until_loop:
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loopStart = run(pos, script);
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if (!READ_LAST_REG()->toBool()) {
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do {
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FREE_REGS(1);
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loopEnd = run(loopStart, script);
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run(pos, script);
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} while (!READ_LAST_REG()->toBool());
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} else {
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loopEnd = loopStart;
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while (*loopEnd != OP_LOOP_END && *loopEnd != OP_HALT)
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loopEnd += instruction_arg_count[*loopEnd++];
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}
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pos = loopEnd;
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DISPATCH();
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do_begin_until_loop:
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return pos;
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do_loop_end:
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return pos;
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do_print:
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std::cout << READ_LAST_REG()->toString() << std::endl;
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FREE_REGS(1);
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DISPATCH();
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do_add:
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REPLACE_RET_VALUE(*READ_REG(0, 2), 2);
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READ_REG(0, 2)->add(READ_REG(1, 2));
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FREE_REGS(1);
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DISPATCH();
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do_subtract:
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REPLACE_RET_VALUE(*READ_REG(0, 2), 2);
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READ_REG(0, 2)->subtract(READ_REG(1, 2));
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FREE_REGS(1);
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DISPATCH();
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do_multiply:
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REPLACE_RET_VALUE(*READ_REG(0, 2), 2);
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READ_REG(0, 2)->multiply(READ_REG(1, 2));
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FREE_REGS(1);
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DISPATCH();
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do_divide:
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REPLACE_RET_VALUE(*READ_REG(0, 2), 2);
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READ_REG(0, 2)->divide(READ_REG(1, 2));
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FREE_REGS(1);
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DISPATCH();
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do_random:
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REPLACE_RET_VALUE(randint<long>(READ_REG(0, 2)->toDouble(), READ_REG(1, 2)->toDouble()), 2);
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FREE_REGS(1);
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DISPATCH();
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do_greater_than:
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REPLACE_RET_VALUE(*READ_REG(0, 2) > *READ_REG(1, 2), 2);
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FREE_REGS(1);
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DISPATCH();
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do_less_than:
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REPLACE_RET_VALUE(*READ_REG(0, 2) < *READ_REG(1, 2), 2);
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FREE_REGS(1);
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DISPATCH();
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do_equals:
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REPLACE_RET_VALUE(*READ_REG(0, 2) == *READ_REG(1, 2), 2);
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FREE_REGS(1);
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DISPATCH();
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do_and:
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REPLACE_RET_VALUE(READ_REG(0, 2)->toBool() && READ_REG(1, 2)->toBool(), 2);
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FREE_REGS(1);
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DISPATCH();
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do_or:
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REPLACE_RET_VALUE(READ_REG(0, 2)->toBool() || READ_REG(1, 2)->toBool(), 2);
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FREE_REGS(1);
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DISPATCH();
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do_not:
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REPLACE_RET_VALUE(!READ_LAST_REG()->toBool(), 1);
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DISPATCH();
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do_set_var:
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*m_variables[*++pos] = *READ_LAST_REG();
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FREE_REGS(1);
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DISPATCH();
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do_read_var:
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ADD_RET_VALUE(*m_variables[*++pos]);
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DISPATCH();
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do_change_var:
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m_variables[*++pos]->add(*READ_LAST_REG());
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FREE_REGS(1);
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DISPATCH();
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do_read_list:
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ADD_RET_VALUE(m_lists[*++pos]->toString());
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DISPATCH();
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do_list_append:
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m_lists[*++pos]->push_back(*READ_LAST_REG());
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FREE_REGS(1);
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DISPATCH();
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do_list_del : {
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const Value *indexValue = READ_LAST_REG();
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size_t index;
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List *list = m_lists[*++pos];
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if (indexValue->isString()) {
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const std::string &str = indexValue->toString();
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if (str == "last") {
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index = list->size();
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} else if (str == "all") {
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list->clear();
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index = 0;
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} else if (str == "random") {
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size_t size = list->size();
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index = size == 0 ? 0 : randint<size_t>(1, size);
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} else
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index = 0;
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} else {
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index = indexValue->toLong();
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FIX_LIST_INDEX(index, list->size());
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}
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if (index != 0)
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list->removeAt(index - 1);
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FREE_REGS(1);
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DISPATCH();
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}
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do_list_del_all:
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m_lists[*++pos]->clear();
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DISPATCH();
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do_list_insert : {
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const Value *indexValue = READ_REG(1, 2);
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size_t index;
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List *list = m_lists[*++pos];
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if (indexValue->isString()) {
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const std::string &str = indexValue->toString();
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if (str == "last") {
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list->push_back(*READ_REG(0, 2));
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index = 0;
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} else if (str == "random") {
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size_t size = list->size();
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index = size == 0 ? 1 : randint<size_t>(1, size);
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} else
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index = 0;
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} else {
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index = indexValue->toLong();
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FIX_LIST_INDEX(index, list->size());
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}
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if ((index != 0) || list->empty()) {
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if (list->empty())
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list->push_back(*READ_REG(0, 2));
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else
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list->insert(index - 1, *READ_REG(0, 2));
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}
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FREE_REGS(2);
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DISPATCH();
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}
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do_list_replace : {
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const Value *indexValue = READ_REG(0, 2);
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size_t index;
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List *list = m_lists[*++pos];
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if (indexValue->isString()) {
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std::string str = indexValue->toString();
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if (str == "last")
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index = list->size();
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else if (str == "random") {
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size_t size = list->size();
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index = size == 0 ? 0 : randint<size_t>(1, size);
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} else
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index = 0;
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} else {
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index = indexValue->toLong();
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FIX_LIST_INDEX(index, list->size());
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}
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if (index != 0)
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list->operator[](index - 1) = *READ_REG(1, 2);
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FREE_REGS(2);
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DISPATCH();
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}
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do_list_get_item : {
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const Value *indexValue = READ_LAST_REG();
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size_t index;
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List *list = m_lists[*++pos];
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if (indexValue->isString()) {
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std::string str = indexValue->toString();
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if (str == "last")
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index = list->size();
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else if (str == "random") {
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size_t size = list->size();
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index = size == 0 ? 0 : randint<size_t>(1, size);
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} else
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index = 0;
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} else {
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index = indexValue->toLong();
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FIX_LIST_INDEX(index, list->size());
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}
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if (index == 0) {
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REPLACE_RET_VALUE("", 1);
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} else {
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REPLACE_RET_VALUE(list->operator[](index - 1), 1);
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}
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DISPATCH();
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}
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do_list_index_of:
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// TODO: Add size_t support to Value and remove the static_cast
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REPLACE_RET_VALUE(static_cast<long>(m_lists[*++pos]->indexOf(*READ_LAST_REG()) + 1), 1);
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DISPATCH();
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do_list_length:
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// TODO: Add size_t support to Value and remove the static_cast
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ADD_RET_VALUE(static_cast<long>(m_lists[*++pos]->size()));
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DISPATCH();
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do_list_contains:
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REPLACE_RET_VALUE(m_lists[*++pos]->contains(*READ_LAST_REG()), 1);
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DISPATCH();
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do_exec:
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m_globalPos = pos;
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m_script = script;
347+
int ret = m_functions[*++pos](this);
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FREE_REGS(ret);
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pos += ret;
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DISPATCH();
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}

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