C++ methodHandle::code_size方法代码示例

// Returns true if m is allowed to be compiled
bool CompilationPolicy::can_be_compiled(methodHandle m, int comp_level) {
  // allow any levels for WhiteBox
  assert(WhiteBoxAPI || comp_level == CompLevel_all || is_compile(comp_level), "illegal compilation level");

  if (m->is_abstract()) return false;
  if (DontCompileHugeMethods && m->code_size() > HugeMethodLimit) return false;

  // Math intrinsics should never be compiled as this can lead to
  // monotonicity problems because the interpreter will prefer the
  // compiled code to the intrinsic version.  This can't happen in
  // production because the invocation counter can't be incremented
  // but we shouldn't expose the system to this problem in testing
  // modes.
  if (!AbstractInterpreter::can_be_compiled(m)) {
    return false;
  }
  if (comp_level == CompLevel_all) {
    if (TieredCompilation) {
      // enough to be compilable at any level for tiered
      return !m->is_not_compilable(CompLevel_simple) || !m->is_not_compilable(CompLevel_full_optimization);
    } else {
      // must be compilable at available level for non-tiered
      return !m->is_not_compilable(CompLevel_highest_tier);
    }
  } else if (is_compile(comp_level)) {
    return !m->is_not_compilable(comp_level);
  }
  return false;
}

AbstractInterpreter::MethodKind AbstractInterpreter::method_kind(methodHandle m) {
  // Abstract method?
  if (m->is_abstract()) return abstract;

  // Invoker for method handles?
  if (m->is_method_handle_invoke())  return method_handle;

  // Native method?
  // Note: This test must come _before_ the test for intrinsic
  //       methods. See also comments below.
  if (m->is_native()) {
    assert(!m->is_method_handle_invoke(), "overlapping bits here, watch out");
    return m->is_synchronized() ? native_synchronized : native;
  }

  // Synchronized?
  if (m->is_synchronized()) {
    return zerolocals_synchronized;
  }

  if (RegisterFinalizersAtInit && m->code_size() == 1 &&
      m->intrinsic_id() == vmIntrinsics::_Object_init) {
    // We need to execute the special return bytecode to check for
    // finalizer registration so create a normal frame.
    return zerolocals;
  }

  // Empty method?
  if (m->is_empty_method()) {
    return empty;
  }

  // Special intrinsic method?
  // Note: This test must come _after_ the test for native methods,
  //       otherwise we will run into problems with JDK 1.2, see also
  //       AbstractInterpreterGenerator::generate_method_entry() for
  //       for details.
  switch (m->intrinsic_id()) {
    case vmIntrinsics::_dsin  : return java_lang_math_sin  ;
    case vmIntrinsics::_dcos  : return java_lang_math_cos  ;
    case vmIntrinsics::_dtan  : return java_lang_math_tan  ;
    case vmIntrinsics::_dabs  : return java_lang_math_abs  ;
    case vmIntrinsics::_dsqrt : return java_lang_math_sqrt ;
    case vmIntrinsics::_dlog  : return java_lang_math_log  ;
    case vmIntrinsics::_dlog10: return java_lang_math_log10;

    case vmIntrinsics::_Reference_get:
                                return java_lang_ref_reference_get;
  }

  // Accessor method?
  if (m->is_accessor()) {
    assert(m->size_of_parameters() == 1, "fast code for accessors assumes parameter size = 1");
    return accessor;
  }

  // Note: for now: zero locals for all non-empty methods
  return zerolocals;
}

// Returns true if m is allowed to be compiled
bool CompilationPolicy::can_be_compiled(methodHandle m, int comp_level) {
    if (m->is_abstract()) return false;
    if (DontCompileHugeMethods && m->code_size() > HugeMethodLimit) return false;

    // Math intrinsics should never be compiled as this can lead to
    // monotonicity problems because the interpreter will prefer the
    // compiled code to the intrinsic version.  This can't happen in
    // production because the invocation counter can't be incremented
    // but we shouldn't expose the system to this problem in testing
    // modes.
    if (!AbstractInterpreter::can_be_compiled(m)) {
        return false;
    }
    if (comp_level == CompLevel_all) {
        return !m->is_not_compilable(CompLevel_simple) && !m->is_not_compilable(CompLevel_full_optimization);
    } else {
        return !m->is_not_compilable(comp_level);
    }
}

AbstractInterpreter::MethodKind AbstractInterpreter::method_kind(methodHandle m) {
  // Abstract method?
  if (m->is_abstract()) return abstract;

  // Method handle primitive?
  if (m->is_method_handle_intrinsic()) {
    vmIntrinsics::ID id = m->intrinsic_id();
    assert(MethodHandles::is_signature_polymorphic(id), "must match an intrinsic");
    MethodKind kind = (MethodKind)( method_handle_invoke_FIRST +
                                    ((int)id - vmIntrinsics::FIRST_MH_SIG_POLY) );
    assert(kind <= method_handle_invoke_LAST, "parallel enum ranges");
    return kind;
  }

#ifndef CC_INTERP
  if (UseCRC32Intrinsics && m->is_native()) {
    // Use optimized stub code for CRC32 native methods.
    switch (m->intrinsic_id()) {
      case vmIntrinsics::_updateCRC32            : return java_util_zip_CRC32_update;
      case vmIntrinsics::_updateBytesCRC32       : return java_util_zip_CRC32_updateBytes;
      case vmIntrinsics::_updateByteBufferCRC32  : return java_util_zip_CRC32_updateByteBuffer;
    }
  }
#endif

  // Native method?
  // Note: This test must come _before_ the test for intrinsic
  //       methods. See also comments below.
  if (m->is_native()) {
    assert(!m->is_method_handle_intrinsic(), "overlapping bits here, watch out");
    return m->is_synchronized() ? native_synchronized : native;
  }

  // Synchronized?
  if (m->is_synchronized()) {
    return zerolocals_synchronized;
  }

  if (RegisterFinalizersAtInit && m->code_size() == 1 &&
      m->intrinsic_id() == vmIntrinsics::_Object_init) {
    // We need to execute the special return bytecode to check for
    // finalizer registration so create a normal frame.
    return zerolocals;
  }

  // Empty method?
  if (m->is_empty_method()) {
    return empty;
  }

  // Special intrinsic method?
  // Note: This test must come _after_ the test for native methods,
  //       otherwise we will run into problems with JDK 1.2, see also
  //       InterpreterGenerator::generate_method_entry() for
  //       for details.
  switch (m->intrinsic_id()) {
    case vmIntrinsics::_dsin  : return java_lang_math_sin  ;
    case vmIntrinsics::_dcos  : return java_lang_math_cos  ;
    case vmIntrinsics::_dtan  : return java_lang_math_tan  ;
    case vmIntrinsics::_dabs  : return java_lang_math_abs  ;
    case vmIntrinsics::_dsqrt : return java_lang_math_sqrt ;
    case vmIntrinsics::_dlog  : return java_lang_math_log  ;
    case vmIntrinsics::_dlog10: return java_lang_math_log10;
    case vmIntrinsics::_dpow  : return java_lang_math_pow  ;
    case vmIntrinsics::_dexp  : return java_lang_math_exp  ;

    case vmIntrinsics::_Reference_get:
                                return java_lang_ref_reference_get;
  }

  // Accessor method?
  if (m->is_accessor()) {
    assert(m->size_of_parameters() == 1, "fast code for accessors assumes parameter size = 1");
    return accessor;
  }

  // Note: for now: zero locals for all non-empty methods
  return zerolocals;
}

// Returns true if m is allowed to be compiled
bool CompilationPolicy::canBeCompiled(methodHandle m) {
  if (m->is_abstract()) return false;
  if (DontCompileHugeMethods && m->code_size() > HugeMethodLimit) return false;

  return !m->is_not_compilable();
}

 // Construction
 BaseBytecodeStream(methodHandle method) : _method(method) {
   set_interval(0, _method->code_size());
   _is_raw = false;
 }