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#ifndef SHARE_PRIMS_METHODCOMPARATOR_HPP
#define SHARE_PRIMS_METHODCOMPARATOR_HPP
#include "interpreter/bytecodeStream.hpp"
#include "oops/constantPool.hpp"
#include "oops/method.hpp"
// methodComparator provides an interface for determining if methods of
// different versions of classes are equivalent or switchable
class MethodComparator {
private:
static BytecodeStream *_s_old, *_s_new;
static ConstantPool* _old_cp;
static ConstantPool* _new_cp;
static bool args_same(Bytecodes::Code c_old, Bytecodes::Code c_new);
static bool pool_constants_same(int cpi_old, int cpi_new);
static int check_stack_and_locals_size(Method* old_method, Method* new_method);
public:
// Check if the new method is equivalent to the old one modulo constant pool (EMCP).
// Intuitive definition: two versions of the same method are EMCP, if they don't differ
// on the source code level. Practically, we check whether the only difference between
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