jdk

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/*
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 * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * This code is free software; you can redistribute it and/or modify it
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 * under the terms of the GNU General Public License version 2 only, as
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 * published by the Free Software Foundation.
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 *
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 * This code is distributed in the hope that it will be useful, but WITHOUT
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * version 2 for more details (a copy is included in the LICENSE file that
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 * accompanied this code).
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 *
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 * You should have received a copy of the GNU General Public License version
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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 *
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 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 * or visit www.oracle.com if you need additional information or have any
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 * questions.
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 *
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 */
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#include "precompiled.hpp"
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#include "asm/assembler.hpp"
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#include "classfile/symbolTable.hpp"
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#include "classfile/systemDictionary.hpp"
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#include "classfile/vmSymbols.hpp"
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#include "memory/oopFactory.hpp"
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#include "memory/resourceArea.hpp"
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#include "memory/universe.hpp"
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#include "oops/instanceKlass.hpp"
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#include "oops/klass.inline.hpp"
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#include "oops/oop.inline.hpp"
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#include "oops/symbol.hpp"
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#include "oops/typeArrayKlass.hpp"
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#include "runtime/fieldDescriptor.inline.hpp"
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#include "runtime/handles.inline.hpp"
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#include "runtime/safepointVerifiers.hpp"
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#include "runtime/sharedRuntime.hpp"
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#include "runtime/signature.hpp"
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#include "runtime/sharedRuntime.hpp"
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// Implementation of SignatureIterator
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// Signature syntax:
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//
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// Signature  = "(" {Parameter} ")" ReturnType.
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// Parameter  = FieldType.
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// ReturnType = FieldType | "V".
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// FieldType  = "B" | "C" | "D" | "F" | "I" | "J" | "S" | "Z" | "L" ClassName ";" | "[" FieldType.
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// ClassName  = string.
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// The ClassName string can be any JVM-style UTF8 string except:
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//  - an empty string (the empty string is never a name of any kind)
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//  - a string which begins or ends with slash '/' (the package separator)
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//  - a string which contains adjacent slashes '//' (no empty package names)
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//  - a string which contains a semicolon ';' (the end-delimiter)
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//  - a string which contains a left bracket '[' (the array marker)
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//  - a string which contains a dot '.' (the external package separator)
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//
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// Other "meta-looking" characters, such as '(' and '<' and '+',
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// are perfectly legitimate within a class name, for the JVM.
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// Class names which contain double slashes ('a//b') and non-initial
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// brackets ('a[b]') are reserved for possible enrichment of the
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// type language.
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void SignatureIterator::set_fingerprint(fingerprint_t fingerprint) {
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  if (!fp_is_valid(fingerprint)) {
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    _fingerprint = fingerprint;
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    _return_type = T_ILLEGAL;
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  } else if (fingerprint != _fingerprint) {
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    assert(_fingerprint == zero_fingerprint(), "consistent fingerprint values");
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    _fingerprint = fingerprint;
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    _return_type = fp_return_type(fingerprint);
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  }
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}
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BasicType SignatureIterator::return_type() {
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  if (_return_type == T_ILLEGAL) {
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    SignatureStream ss(_signature);
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    ss.skip_to_return_type();
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    _return_type = ss.type();
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    assert(_return_type != T_ILLEGAL, "illegal return type");
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  }
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  return _return_type;
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}
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bool SignatureIterator::fp_is_valid_type(BasicType type, bool for_return_type) {
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  assert(type != (BasicType)fp_parameters_done, "fingerprint is incorrectly at done");
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  assert(((int)type & ~fp_parameter_feature_mask) == 0, "fingerprint feature mask yielded non-zero value");
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  return (is_java_primitive(type) ||
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          is_reference_type(type) ||
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          (for_return_type && type == T_VOID));
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}
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ArgumentSizeComputer::ArgumentSizeComputer(Symbol* signature)
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  : SignatureIterator(signature)
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{
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  _size = 0;
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  do_parameters_on(this);  // non-virtual template execution
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}
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ArgumentCount::ArgumentCount(Symbol* signature)
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  : SignatureIterator(signature)
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{
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  _size = 0;
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  do_parameters_on(this);  // non-virtual template execution
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}
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ReferenceArgumentCount::ReferenceArgumentCount(Symbol* signature)
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  : SignatureIterator(signature)
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{
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  _refs = 0;
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  do_parameters_on(this);  // non-virtual template execution
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}
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#if !defined(_LP64) || defined(ZERO) || defined(ASSERT)
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static int compute_num_stack_arg_slots(Symbol* signature, int sizeargs, bool is_static) {
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  ResourceMark rm;
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  BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
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  VMRegPair* regs   = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
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  int sig_index = 0;
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  if (!is_static) {
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    sig_bt[sig_index++] = T_OBJECT; // 'this'
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  }
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  for (SignatureStream ss(signature); !ss.at_return_type(); ss.next()) {
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    BasicType t = ss.type();
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    assert(type2size[t] == 1 || type2size[t] == 2, "size is 1 or 2");
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    sig_bt[sig_index++] = t;
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    if (type2size[t] == 2) {
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      sig_bt[sig_index++] = T_VOID;
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    }
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  }
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  assert(sig_index == sizeargs, "sig_index: %d sizeargs: %d", sig_index, sizeargs);
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  return SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs);
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}
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#endif
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void Fingerprinter::compute_fingerprint_and_return_type(bool static_flag) {
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  // See if we fingerprinted this method already
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  if (_method != nullptr) {
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    assert(!static_flag, "must not be passed by caller");
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    static_flag = _method->is_static();
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    _fingerprint = _method->constMethod()->fingerprint();
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    if (_fingerprint != zero_fingerprint()) {
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      _return_type = _method->result_type();
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      assert(is_java_type(_return_type), "return type must be a java type");
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      return;
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    }
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    if (_method->size_of_parameters() > fp_max_size_of_parameters) {
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      _fingerprint = overflow_fingerprint();
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      _method->constMethod()->set_fingerprint(_fingerprint);
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      // as long as we are here compute the return type:
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      _return_type = ResultTypeFinder(_method->signature()).type();
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      assert(is_java_type(_return_type), "return type must be a java type");
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      return;
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    }
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  }
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  // Note:  This will always take the slow path, since _fp==zero_fp.
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  initialize_accumulator();
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  initialize_calling_convention(static_flag);
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  do_parameters_on(this);
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  assert(fp_is_valid_type(_return_type, true), "bad result type");
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  // Fill in the return type and static bits:
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  _accumulator |= _return_type << fp_static_feature_size;
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  if (static_flag) {
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    _accumulator |= fp_is_static_bit;
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  } else {
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    _param_size += 1;  // this is the convention for Method::compute_size_of_parameters
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  }
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#if defined(_LP64) && !defined(ZERO)
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#ifdef ASSERT
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  int dbg_stack_arg_slots = compute_num_stack_arg_slots(_signature, _param_size, static_flag);
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  assert(_stack_arg_slots == dbg_stack_arg_slots, "fingerprinter: %d full: %d", _stack_arg_slots, dbg_stack_arg_slots);
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#endif
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#else
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  // Fallback: computed _stack_arg_slots is unreliable, compute directly.
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  _stack_arg_slots = compute_num_stack_arg_slots(_signature, _param_size, static_flag);
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#endif
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  // Detect overflow.  (We counted _param_size correctly.)
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  if (_method == nullptr && _param_size > fp_max_size_of_parameters) {
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    // We did a one-pass computation of argument size, return type,
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    // and fingerprint.
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    _fingerprint = overflow_fingerprint();
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    return;
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  }
197

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  assert(_shift_count < BitsPerLong,
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         "shift count overflow %d (%d vs. %d): %s",
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         _shift_count, _param_size, fp_max_size_of_parameters,
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         _signature->as_C_string());
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  assert((_accumulator >> _shift_count) == fp_parameters_done, "must be zero");
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  // This is the result, along with _return_type:
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  _fingerprint = _accumulator;
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  // Cache the result on the method itself:
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  if (_method != nullptr) {
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    _method->constMethod()->set_fingerprint(_fingerprint);
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  }
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}
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void Fingerprinter::initialize_calling_convention(bool static_flag) {
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  _int_args = 0;
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  _fp_args = 0;
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  if (!static_flag) { // `this` takes up an int register
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    _int_args++;
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  }
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}
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void Fingerprinter::do_type_calling_convention(BasicType type) {
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  // We compute the number of slots for stack-passed arguments in compiled calls.
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  // TODO: SharedRuntime::java_calling_convention is the shared code that knows all details
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  // about the platform-specific calling conventions. This method tries to compute the stack
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  // args number... poorly, at least for 32-bit ports and for zero. Current code has the fallback
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  // that recomputes the stack args number from SharedRuntime::java_calling_convention.
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#if defined(_LP64) && !defined(ZERO)
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  switch (type) {
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  case T_VOID:
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    break;
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  case T_BOOLEAN:
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  case T_CHAR:
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  case T_BYTE:
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  case T_SHORT:
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  case T_INT:
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    if (_int_args < Argument::n_int_register_parameters_j) {
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      _int_args++;
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    } else {
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#if defined(PPC64) || defined(S390)
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      _stack_arg_slots += 1;
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#else
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      _stack_arg_slots = align_up(_stack_arg_slots, 2);
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      _stack_arg_slots += 1;
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#endif // defined(PPC64) || defined(S390)
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    }
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    break;
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  case T_LONG:
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  case T_OBJECT:
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  case T_ARRAY:
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  case T_ADDRESS:
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    if (_int_args < Argument::n_int_register_parameters_j) {
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      _int_args++;
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    } else {
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      _stack_arg_slots = align_up(_stack_arg_slots, 2);
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      _stack_arg_slots += 2;
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    }
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    break;
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  case T_FLOAT:
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    if (_fp_args < Argument::n_float_register_parameters_j) {
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      _fp_args++;
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    } else {
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#if defined(PPC64) || defined(S390)
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      _stack_arg_slots += 1;
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#else
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      _stack_arg_slots = align_up(_stack_arg_slots, 2);
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      _stack_arg_slots += 1;
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#endif // defined(PPC64) || defined(S390)
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    }
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    break;
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  case T_DOUBLE:
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    if (_fp_args < Argument::n_float_register_parameters_j) {
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      _fp_args++;
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    } else {
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      _stack_arg_slots = align_up(_stack_arg_slots, 2);
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      _stack_arg_slots += 2;
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    }
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    break;
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  default:
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    ShouldNotReachHere();
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    break;
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  }
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#endif
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}
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// Implementation of SignatureStream
287

288
static inline BasicType decode_signature_char(int ch) {
289
  switch (ch) {
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#define EACH_SIG(ch, bt, ignore) \
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    case ch: return bt;
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    SIGNATURE_TYPES_DO(EACH_SIG, ignore)
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#undef EACH_SIG
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  }
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  return (BasicType)0;
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}
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SignatureStream::SignatureStream(const Symbol* signature,
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                                 bool is_method) {
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  assert(!is_method || signature->starts_with(JVM_SIGNATURE_FUNC),
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         "method signature required");
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  _signature = signature;
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  _limit = signature->utf8_length();
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  int oz = (is_method ? _s_method : _s_field);
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  _state = oz;
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  _begin = _end = oz; // skip first '(' in method signatures
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  _array_prefix = 0;  // just for definiteness
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309
  // assigning java/lang/Object to _previous_name means we can
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  // avoid a number of null checks in the parser
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  _previous_name = vmSymbols::java_lang_Object();
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  _names = nullptr;
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  next();
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}
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316
SignatureStream::~SignatureStream() {
317
  if (_previous_name == vmSymbols::java_lang_Object()) {
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    // no names were created
319
    assert(_names == nullptr, "_names unexpectedly created");
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    return;
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  }
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323
  // decrement refcount for names created during signature parsing
324
  _previous_name->decrement_refcount();
325
  if (_names != nullptr) {
326
    for (int i = 0; i < _names->length(); i++) {
327
      _names->at(i)->decrement_refcount();
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    }
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  }
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}
331

332
inline int SignatureStream::scan_type(BasicType type) {
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  const u1* base = _signature->bytes();
334
  int end = _end;
335
  int limit = _limit;
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  const u1* tem;
337
  switch (type) {
338
  case T_OBJECT:
339
    tem = (const u1*) memchr(&base[end], JVM_SIGNATURE_ENDCLASS, limit - end);
340
    return (tem == nullptr ? limit : pointer_delta_as_int(tem + 1, base));
341

342
  case T_ARRAY:
343
    while ((end < limit) && ((char)base[end] == JVM_SIGNATURE_ARRAY)) { end++; }
344
    // If we discovered only the string of '[', this means something is wrong.
345
    if (end >= limit) {
346
      assert(false, "Invalid type detected");
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      return limit;
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    }
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    _array_prefix = end - _end;  // number of '[' chars just skipped
350
    if (Signature::has_envelope(base[end])) {
351
      tem = (const u1 *) memchr(&base[end], JVM_SIGNATURE_ENDCLASS, limit - end);
352
      return (tem == nullptr ? limit : pointer_delta_as_int(tem + 1, base));
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    }
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    // Skipping over a single character for a primitive type.
355
    assert(is_java_primitive(decode_signature_char(base[end])), "only primitives expected");
356
    return end + 1;
357

358
  default:
359
    // Skipping over a single character for a primitive type (or void).
360
    assert(!is_reference_type(type), "only primitives or void expected");
361
    return end + 1;
362
  }
363
}
364

365
void SignatureStream::next() {
366
  const Symbol* sig = _signature;
367
  int len = _limit;
368
  if (_end >= len) { set_done(); return; }
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  _begin = _end;
370
  int ch = sig->char_at(_begin);
371
  if (ch == JVM_SIGNATURE_ENDFUNC) {
372
    assert(_state == _s_method, "must be in method");
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    _state = _s_method_return;
374
    _begin = ++_end;
375
    if (_end >= len) { set_done(); return; }
376
    ch = sig->char_at(_begin);
377
  }
378
  BasicType bt = decode_signature_char(ch);
379
  assert(ch == type2char(bt), "bad signature char %c/%d", ch, ch);
380
  _type = bt;
381
  _end = scan_type(bt);
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}
383

384
int SignatureStream::skip_whole_array_prefix() {
385
  assert(_type == T_ARRAY, "must be");
386

387
  // we are stripping all levels of T_ARRAY,
388
  // so we must decode the next character
389
  int whole_array_prefix = _array_prefix;
390
  int new_begin = _begin + whole_array_prefix;
391
  _begin = new_begin;
392
  int ch = _signature->char_at(new_begin);
393
  BasicType bt = decode_signature_char(ch);
394
  assert(ch == type2char(bt), "bad signature char %c/%d", ch, ch);
395
  _type = bt;
396
  assert(bt != T_VOID && bt != T_ARRAY, "bad signature type");
397
  // Don't bother to re-scan, since it won't change the value of _end.
398
  return whole_array_prefix;
399
}
400

401
bool Signature::is_valid_array_signature(const Symbol* sig) {
402
  assert(sig->utf8_length() > 1, "this should already have been checked");
403
  assert(sig->char_at(0) == JVM_SIGNATURE_ARRAY, "this should already have been checked");
404
  // The first character is already checked
405
  int i = 1;
406
  int len = sig->utf8_length();
407
  // First skip all '['s
408
  while(i < len - 1 && sig->char_at(i) == JVM_SIGNATURE_ARRAY) i++;
409

410
  // Check type
411
  switch(sig->char_at(i)) {
412
  case JVM_SIGNATURE_BYTE:
413
  case JVM_SIGNATURE_CHAR:
414
  case JVM_SIGNATURE_DOUBLE:
415
  case JVM_SIGNATURE_FLOAT:
416
  case JVM_SIGNATURE_INT:
417
  case JVM_SIGNATURE_LONG:
418
  case JVM_SIGNATURE_SHORT:
419
  case JVM_SIGNATURE_BOOLEAN:
420
    // If it is an array, the type is the last character
421
    return (i + 1 == len);
422
  case JVM_SIGNATURE_CLASS:
423
    // If it is an object, the last character must be a ';'
424
    return sig->char_at(len - 1) == JVM_SIGNATURE_ENDCLASS;
425
  }
426
  return false;
427
}
428

429
BasicType Signature::basic_type(int ch) {
430
  BasicType btcode = decode_signature_char(ch);
431
  if (btcode == 0)  return T_ILLEGAL;
432
  return btcode;
433
}
434

435
Symbol* Signature::strip_envelope(const Symbol* signature) {
436
  assert(has_envelope(signature), "precondition");
437
  return SymbolTable::new_symbol((char*) signature->bytes() + 1,
438
                                 signature->utf8_length() - 2);
439
}
440

441
static const int jl_len = 10, object_len = 6, jl_object_len = jl_len + object_len;
442
static const char jl_str[] = "java/lang/";
443

444
#ifdef ASSERT
445
static bool signature_symbols_sane() {
446
  static bool done;
447
  if (done)  return true;
448
  done = true;
449
  // test some tense code that looks for common symbol names:
450
  assert(vmSymbols::java_lang_Object()->utf8_length() == jl_object_len &&
451
         vmSymbols::java_lang_Object()->starts_with(jl_str, jl_len) &&
452
         vmSymbols::java_lang_Object()->ends_with("Object", object_len) &&
453
         vmSymbols::java_lang_Object()->is_permanent() &&
454
         vmSymbols::java_lang_String()->utf8_length() == jl_object_len &&
455
         vmSymbols::java_lang_String()->starts_with(jl_str, jl_len) &&
456
         vmSymbols::java_lang_String()->ends_with("String", object_len) &&
457
         vmSymbols::java_lang_String()->is_permanent(),
458
         "sanity");
459
  return true;
460
}
461
#endif //ASSERT
462

463
// returns a symbol; the caller is responsible for decrementing it
464
Symbol* SignatureStream::find_symbol() {
465
  // Create a symbol from for string _begin _end
466
  int begin = raw_symbol_begin();
467
  int end   = raw_symbol_end();
468

469
  const char* symbol_chars = (const char*)_signature->base() + begin;
470
  int len = end - begin;
471

472
  // Quick check for common symbols in signatures
473
  assert(signature_symbols_sane(), "incorrect signature sanity check");
474
  if (len == jl_object_len &&
475
      memcmp(symbol_chars, jl_str, jl_len) == 0) {
476
    if (memcmp("String", symbol_chars + jl_len, object_len) == 0) {
477
      return vmSymbols::java_lang_String();
478
    } else if (memcmp("Object", symbol_chars + jl_len, object_len) == 0) {
479
      return vmSymbols::java_lang_Object();
480
    }
481
  }
482

483
  Symbol* name = _previous_name;
484
  if (name->equals(symbol_chars, len)) {
485
    return name;
486
  }
487

488
  // Save names for cleaning up reference count at the end of
489
  // SignatureStream scope.
490
  name = SymbolTable::new_symbol(symbol_chars, len);
491

492
  // Only allocate the GrowableArray for the _names buffer if more than
493
  // one name is being processed in the signature.
494
  if (!_previous_name->is_permanent()) {
495
    if (_names == nullptr) {
496
      _names = new GrowableArray<Symbol*>(10);
497
    }
498
    _names->push(_previous_name);
499
  }
500
  _previous_name = name;
501
  return name;
502
}
503

504
Klass* SignatureStream::as_klass(Handle class_loader, Handle protection_domain,
505
                                 FailureMode failure_mode, TRAPS) {
506
  if (!is_reference()) {
507
    return nullptr;
508
  }
509
  Symbol* name = as_symbol();
510
  Klass* k = nullptr;
511
  if (failure_mode == ReturnNull) {
512
    // Note:  SD::resolve_or_null returns null for most failure modes,
513
    // but not all.  Circularity errors, invalid PDs, etc., throw.
514
    k = SystemDictionary::resolve_or_null(name, class_loader, protection_domain, CHECK_NULL);
515
  } else if (failure_mode == CachedOrNull) {
516
    NoSafepointVerifier nsv;  // no loading, now, we mean it!
517
    assert(!HAS_PENDING_EXCEPTION, "");
518
    k = SystemDictionary::find_instance_klass(THREAD, name, class_loader, protection_domain);
519
    // SD::find does not trigger loading, so there should be no throws
520
    // Still, bad things can happen, so we CHECK_NULL and ask callers
521
    // to do likewise.
522
    return k;
523
  } else {
524
    // The only remaining failure mode is NCDFError.
525
    // The test here allows for an additional mode CNFException
526
    // if callers need to request the reflective error instead.
527
    bool throw_error = (failure_mode == NCDFError);
528
    k = SystemDictionary::resolve_or_fail(name, class_loader, protection_domain, throw_error, CHECK_NULL);
529
  }
530

531
  return k;
532
}
533

534
oop SignatureStream::as_java_mirror(Handle class_loader, Handle protection_domain,
535
                                    FailureMode failure_mode, TRAPS) {
536
  if (!is_reference()) {
537
    return Universe::java_mirror(type());
538
  }
539
  Klass* klass = as_klass(class_loader, protection_domain, failure_mode, CHECK_NULL);
540
  if (klass == nullptr) {
541
    return nullptr;
542
  }
543
  return klass->java_mirror();
544
}
545

546
void SignatureStream::skip_to_return_type() {
547
  while (!at_return_type()) {
548
    next();
549
  }
550
}
551

552
ResolvingSignatureStream::ResolvingSignatureStream(Symbol* signature,
553
                                                   Handle class_loader,
554
                                                   Handle protection_domain,
555
                                                   bool is_method)
556
  : SignatureStream(signature, is_method),
557
    _class_loader(class_loader), _protection_domain(protection_domain)
558
{
559
  initialize_load_origin(nullptr);
560
}
561

562
ResolvingSignatureStream::ResolvingSignatureStream(Symbol* signature, Klass* load_origin, bool is_method)
563
  : SignatureStream(signature, is_method)
564
{
565
  assert(load_origin != nullptr, "");
566
  initialize_load_origin(load_origin);
567
}
568

569
ResolvingSignatureStream::ResolvingSignatureStream(const Method* method)
570
  : SignatureStream(method->signature(), true)
571
{
572
  initialize_load_origin(method->method_holder());
573
}
574

575
void ResolvingSignatureStream::cache_handles() {
576
  assert(_load_origin != nullptr, "");
577
  JavaThread* current = JavaThread::current();
578
  _class_loader = Handle(current, _load_origin->class_loader());
579
  _protection_domain = Handle(current, _load_origin->protection_domain());
580
}
581

582
#ifdef ASSERT
583

584
extern bool signature_constants_sane(); // called from basic_types_init()
585

586
bool signature_constants_sane() {
587
  // for the lookup table, test every 8-bit code point, and then some:
588
  for (int i = -256; i <= 256; i++) {
589
    int btcode = 0;
590
    switch (i) {
591
#define EACH_SIG(ch, bt, ignore) \
592
    case ch: { btcode = bt; break; }
593
    SIGNATURE_TYPES_DO(EACH_SIG, ignore)
594
#undef EACH_SIG
595
    }
596
    int btc = decode_signature_char(i);
597
    assert(btc == btcode, "misconfigured table: %d => %d not %d", i, btc, btcode);
598
  }
599
  return true;
600
}
601

602
bool SignatureVerifier::is_valid_method_signature(Symbol* sig) {
603
  const char* method_sig = (const char*)sig->bytes();
604
  ssize_t len = sig->utf8_length();
605
  ssize_t index = 0;
606
  if (method_sig != nullptr && len > 1 && method_sig[index] == JVM_SIGNATURE_FUNC) {
607
    ++index;
608
    while (index < len && method_sig[index] != JVM_SIGNATURE_ENDFUNC) {
609
      ssize_t res = is_valid_type(&method_sig[index], len - index);
610
      if (res == -1) {
611
        return false;
612
      } else {
613
        index += res;
614
      }
615
    }
616
    if (index < len && method_sig[index] == JVM_SIGNATURE_ENDFUNC) {
617
      // check the return type
618
      ++index;
619
      return (is_valid_type(&method_sig[index], len - index) == (len - index));
620
    }
621
  }
622
  return false;
623
}
624

625
bool SignatureVerifier::is_valid_type_signature(Symbol* sig) {
626
  const char* type_sig = (const char*)sig->bytes();
627
  ssize_t len = sig->utf8_length();
628
  return (type_sig != nullptr && len >= 1 &&
629
          (is_valid_type(type_sig, len) == len));
630
}
631

632
// Checks to see if the type (not to go beyond 'limit') refers to a valid type.
633
// Returns -1 if it is not, or the index of the next character that is not part
634
// of the type.  The type encoding may end before 'limit' and that's ok.
635
ssize_t SignatureVerifier::is_valid_type(const char* type, ssize_t limit) {
636
  ssize_t index = 0;
637

638
  // Iterate over any number of array dimensions
639
  while (index < limit && type[index] == JVM_SIGNATURE_ARRAY) ++index;
640
  if (index >= limit) {
641
    return -1;
642
  }
643
  switch (type[index]) {
644
    case JVM_SIGNATURE_BYTE:
645
    case JVM_SIGNATURE_CHAR:
646
    case JVM_SIGNATURE_FLOAT:
647
    case JVM_SIGNATURE_DOUBLE:
648
    case JVM_SIGNATURE_INT:
649
    case JVM_SIGNATURE_LONG:
650
    case JVM_SIGNATURE_SHORT:
651
    case JVM_SIGNATURE_BOOLEAN:
652
    case JVM_SIGNATURE_VOID:
653
      return index + 1;
654
    case JVM_SIGNATURE_CLASS:
655
      for (index = index + 1; index < limit; ++index) {
656
        char c = type[index];
657
        switch (c) {
658
          case JVM_SIGNATURE_ENDCLASS:
659
            return index + 1;
660
          case '\0': case JVM_SIGNATURE_DOT: case JVM_SIGNATURE_ARRAY:
661
            return -1;
662
          default: ; // fall through
663
        }
664
      }
665
      // fall through
666
    default: ; // fall through
667
  }
668
  return -1;
669
}
670

671
#endif // ASSERT
672