从openjdk17 C++源码角度看 java类成员变量是怎么赋值的

##java源码

public class OtherClass {public static int CONSTANT_O=9876;public int o=1234;public void dddd(){String dddd = "dddd";//System.out.println(dddd);System.out.println(dddd+CONSTANT_O);}}

public int o=1234;

在openjdk17中 C++源码怎么执行这段代码的，字节码sipush ，putfield      #2

##字节码

 public OtherClass();descriptor: ()Vflags: (0x0001) ACC_PUBLICCode:stack=2, locals=1, args_size=10: aload_01: invokespecial #1                  // Method java/lang/Object."<init>":()V4: aload_05: sipush        12348: putfield      #2                  // Field o:I11: returnLineNumberTable:line 1: 0line 4: 4

##C++源码

// This function is the interface to the assembly code. It returns the resolved
// cpCache entry.  This doesn't safepoint, but the helper routines safepoint.
// This function will check for redefinition!
JRT_ENTRY(void, InterpreterRuntime::resolve_from_cache(JavaThread* current, Bytecodes::Code bytecode)) {switch (bytecode) {case Bytecodes::_getstatic:case Bytecodes::_putstatic:case Bytecodes::_getfield:case Bytecodes::_putfield:resolve_get_put(current, bytecode);break;case Bytecodes::_invokevirtual:case Bytecodes::_invokespecial:case Bytecodes::_invokestatic:case Bytecodes::_invokeinterface:resolve_invoke(current, bytecode);break;case Bytecodes::_invokehandle:resolve_invokehandle(current);break;case Bytecodes::_invokedynamic:resolve_invokedynamic(current);break;default:fatal("unexpected bytecode: %s", Bytecodes::name(bytecode));break;}
}
JRT_ENDvoid InterpreterRuntime::resolve_get_put(JavaThread* current, Bytecodes::Code bytecode) {// resolve fieldfieldDescriptor info;LastFrameAccessor last_frame(current);constantPoolHandle pool(current, last_frame.method()->constants());methodHandle m(current, last_frame.method());bool is_put    = (bytecode == Bytecodes::_putfield  || bytecode == Bytecodes::_nofast_putfield ||bytecode == Bytecodes::_putstatic);bool is_static = (bytecode == Bytecodes::_getstatic || bytecode == Bytecodes::_putstatic);{JvmtiHideSingleStepping jhss(current);JavaThread* THREAD = current; // For exception macros.LinkResolver::resolve_field_access(info, pool, last_frame.get_index_u2_cpcache(bytecode),m, bytecode, CHECK);} // end JvmtiHideSingleStepping// std::cout << "@@@@yym%%%%field" << info.name()->as_C_string() << ":offset:" << info.offset() << std::endl;// check if link resolution caused cpCache to be updatedConstantPoolCacheEntry* cp_cache_entry = last_frame.cache_entry();if (cp_cache_entry->is_resolved(bytecode)) {// std::cout << "@@@@yym%%%%field is_resolved" << info.name()->as_C_string() << ":result:" << "true" << std::endl;return;}// compute auxiliary field attributesTosState state  = as_TosState(info.field_type());// Resolution of put instructions on final fields is delayed. That is required so that// exceptions are thrown at the correct place (when the instruction is actually invoked).// If we do not resolve an instruction in the current pass, leaving the put_code// set to zero will cause the next put instruction to the same field to reresolve.// Resolution of put instructions to final instance fields with invalid updates (i.e.,// to final instance fields with updates originating from a method different than <init>)// is inhibited. A putfield instruction targeting an instance final field must throw// an IllegalAccessError if the instruction is not in an instance// initializer method <init>. If resolution were not inhibited, a putfield// in an initializer method could be resolved in the initializer. Subsequent// putfield instructions to the same field would then use cached information.// As a result, those instructions would not pass through the VM. That is,// checks in resolve_field_access() would not be executed for those instructions// and the required IllegalAccessError would not be thrown.//// Also, we need to delay resolving getstatic and putstatic instructions until the// class is initialized.  This is required so that access to the static// field will call the initialization function every time until the class// is completely initialized ala. in 2.17.5 in JVM Specification.InstanceKlass* klass = info.field_holder();bool uninitialized_static = is_static && !klass->is_initialized();bool has_initialized_final_update = info.field_holder()->major_version() >= 53 &&info.has_initialized_final_update();assert(!(has_initialized_final_update && !info.access_flags().is_final()), "Fields with initialized final updates must be final");Bytecodes::Code get_code = (Bytecodes::Code)0;Bytecodes::Code put_code = (Bytecodes::Code)0;if (!uninitialized_static) {get_code = ((is_static) ? Bytecodes::_getstatic : Bytecodes::_getfield);if ((is_put && !has_initialized_final_update) || !info.access_flags().is_final()) {put_code = ((is_static) ? Bytecodes::_putstatic : Bytecodes::_putfield);}}// std::cout << "@@@@yym%%%%field" << info.name()->as_C_string() << ":offset:" << info.offset() << std::endl;// std::string str1 = "o";// const char* cStr = info.name()->as_klass_external_name();  // std::string str2(cStr); // 使用构造函数进行转换// if (str1.compare(str2) == 0) {//     std::cout << "field name The strings are equal." << std::endl;//     std::cout << "@@@@yym%%%%field" << info.name()->as_C_string() << ":offset:" << info.offset() << std::endl;// }// std::string str3 = "CONSTANT_O";// const char* cStr1 = info.name()->as_klass_external_name();  // std::string str4(cStr1); // 使用构造函数进行转换// if (str3.compare(str4) == 0) {//     std::cout << "CONSTANT_O name The strings are equal." << std::endl;//     std::cout << "@@@@yym%%%%field" << info.name()->as_C_string() << ":offset:" << info.offset() << std::endl;// }cp_cache_entry->set_field(get_code,put_code,info.field_holder(),info.index(),info.offset(),state,info.access_flags().is_final(),info.access_flags().is_volatile());
}