view src/cpu/x86/vm/stubGenerator_x86_64.cpp @ 2368:dde920245681

6896099: Integrate CMS heap ergo with default heap sizing ergo 6627787: CMS: JVM refuses to start up with -Xms16m -Xmx16m 7000125: CMS: Anti-monotone young gen sizing with respect to maximum whole heap size specification 7027529: CMS: retire CMSUseOldDefaults flag Summary: Simplify CMS heap sizing code, relying on ergonomic initial sizing consistent with other collectors for the most part, controlling only young gen sizing to rein in pause times. Make CMS young gen sizing default statically cpu-dependant. Remove inconsistencies wrt generation sizing and policy code, allowing for the fixing for 6627787 and 7000125. For 7027529, retire the flag CMSUseOldDefaults which had been introduced as a bridge from JDK 5 to JDK 6 a number of years ago. Reviewed-by: brutisso, poonam
author ysr
date Wed, 16 Mar 2011 10:37:08 -0700
parents bbefa3ca1543
children d89a22843c62
line wrap: on
line source

/*
 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

#include "precompiled.hpp"
#include "asm/assembler.hpp"
#include "assembler_x86.inline.hpp"
#include "interpreter/interpreter.hpp"
#include "nativeInst_x86.hpp"
#include "oops/instanceOop.hpp"
#include "oops/methodOop.hpp"
#include "oops/objArrayKlass.hpp"
#include "oops/oop.inline.hpp"
#include "prims/methodHandles.hpp"
#include "runtime/frame.inline.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/stubCodeGenerator.hpp"
#include "runtime/stubRoutines.hpp"
#include "utilities/top.hpp"
#ifdef TARGET_OS_FAMILY_linux
# include "thread_linux.inline.hpp"
#endif
#ifdef TARGET_OS_FAMILY_solaris
# include "thread_solaris.inline.hpp"
#endif
#ifdef TARGET_OS_FAMILY_windows
# include "thread_windows.inline.hpp"
#endif
#ifdef COMPILER2
#include "opto/runtime.hpp"
#endif

// Declaration and definition of StubGenerator (no .hpp file).
// For a more detailed description of the stub routine structure
// see the comment in stubRoutines.hpp

#define __ _masm->
#define TIMES_OOP (UseCompressedOops ? Address::times_4 : Address::times_8)
#define a__ ((Assembler*)_masm)->

#ifdef PRODUCT
#define BLOCK_COMMENT(str) /* nothing */
#else
#define BLOCK_COMMENT(str) __ block_comment(str)
#endif

#define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
const int MXCSR_MASK = 0xFFC0;  // Mask out any pending exceptions

// Stub Code definitions

static address handle_unsafe_access() {
  JavaThread* thread = JavaThread::current();
  address pc = thread->saved_exception_pc();
  // pc is the instruction which we must emulate
  // doing a no-op is fine:  return garbage from the load
  // therefore, compute npc
  address npc = Assembler::locate_next_instruction(pc);

  // request an async exception
  thread->set_pending_unsafe_access_error();

  // return address of next instruction to execute
  return npc;
}

class StubGenerator: public StubCodeGenerator {
 private:

#ifdef PRODUCT
#define inc_counter_np(counter) (0)
#else
  void inc_counter_np_(int& counter) {
    __ incrementl(ExternalAddress((address)&counter));
  }
#define inc_counter_np(counter) \
  BLOCK_COMMENT("inc_counter " #counter); \
  inc_counter_np_(counter);
#endif

  // Call stubs are used to call Java from C
  //
  // Linux Arguments:
  //    c_rarg0:   call wrapper address                   address
  //    c_rarg1:   result                                 address
  //    c_rarg2:   result type                            BasicType
  //    c_rarg3:   method                                 methodOop
  //    c_rarg4:   (interpreter) entry point              address
  //    c_rarg5:   parameters                             intptr_t*
  //    16(rbp): parameter size (in words)              int
  //    24(rbp): thread                                 Thread*
  //
  //     [ return_from_Java     ] <--- rsp
  //     [ argument word n      ]
  //      ...
  // -12 [ argument word 1      ]
  // -11 [ saved r15            ] <--- rsp_after_call
  // -10 [ saved r14            ]
  //  -9 [ saved r13            ]
  //  -8 [ saved r12            ]
  //  -7 [ saved rbx            ]
  //  -6 [ call wrapper         ]
  //  -5 [ result               ]
  //  -4 [ result type          ]
  //  -3 [ method               ]
  //  -2 [ entry point          ]
  //  -1 [ parameters           ]
  //   0 [ saved rbp            ] <--- rbp
  //   1 [ return address       ]
  //   2 [ parameter size       ]
  //   3 [ thread               ]
  //
  // Windows Arguments:
  //    c_rarg0:   call wrapper address                   address
  //    c_rarg1:   result                                 address
  //    c_rarg2:   result type                            BasicType
  //    c_rarg3:   method                                 methodOop
  //    48(rbp): (interpreter) entry point              address
  //    56(rbp): parameters                             intptr_t*
  //    64(rbp): parameter size (in words)              int
  //    72(rbp): thread                                 Thread*
  //
  //     [ return_from_Java     ] <--- rsp
  //     [ argument word n      ]
  //      ...
  //  -8 [ argument word 1      ]
  //  -7 [ saved r15            ] <--- rsp_after_call
  //  -6 [ saved r14            ]
  //  -5 [ saved r13            ]
  //  -4 [ saved r12            ]
  //  -3 [ saved rdi            ]
  //  -2 [ saved rsi            ]
  //  -1 [ saved rbx            ]
  //   0 [ saved rbp            ] <--- rbp
  //   1 [ return address       ]
  //   2 [ call wrapper         ]
  //   3 [ result               ]
  //   4 [ result type          ]
  //   5 [ method               ]
  //   6 [ entry point          ]
  //   7 [ parameters           ]
  //   8 [ parameter size       ]
  //   9 [ thread               ]
  //
  //    Windows reserves the callers stack space for arguments 1-4.
  //    We spill c_rarg0-c_rarg3 to this space.

  // Call stub stack layout word offsets from rbp
  enum call_stub_layout {
#ifdef _WIN64
    rsp_after_call_off = -7,
    r15_off            = rsp_after_call_off,
    r14_off            = -6,
    r13_off            = -5,
    r12_off            = -4,
    rdi_off            = -3,
    rsi_off            = -2,
    rbx_off            = -1,
    rbp_off            =  0,
    retaddr_off        =  1,
    call_wrapper_off   =  2,
    result_off         =  3,
    result_type_off    =  4,
    method_off         =  5,
    entry_point_off    =  6,
    parameters_off     =  7,
    parameter_size_off =  8,
    thread_off         =  9
#else
    rsp_after_call_off = -12,
    mxcsr_off          = rsp_after_call_off,
    r15_off            = -11,
    r14_off            = -10,
    r13_off            = -9,
    r12_off            = -8,
    rbx_off            = -7,
    call_wrapper_off   = -6,
    result_off         = -5,
    result_type_off    = -4,
    method_off         = -3,
    entry_point_off    = -2,
    parameters_off     = -1,
    rbp_off            =  0,
    retaddr_off        =  1,
    parameter_size_off =  2,
    thread_off         =  3
#endif
  };

  address generate_call_stub(address& return_address) {
    assert((int)frame::entry_frame_after_call_words == -(int)rsp_after_call_off + 1 &&
           (int)frame::entry_frame_call_wrapper_offset == (int)call_wrapper_off,
           "adjust this code");
    StubCodeMark mark(this, "StubRoutines", "call_stub");
    address start = __ pc();

    // same as in generate_catch_exception()!
    const Address rsp_after_call(rbp, rsp_after_call_off * wordSize);

    const Address call_wrapper  (rbp, call_wrapper_off   * wordSize);
    const Address result        (rbp, result_off         * wordSize);
    const Address result_type   (rbp, result_type_off    * wordSize);
    const Address method        (rbp, method_off         * wordSize);
    const Address entry_point   (rbp, entry_point_off    * wordSize);
    const Address parameters    (rbp, parameters_off     * wordSize);
    const Address parameter_size(rbp, parameter_size_off * wordSize);

    // same as in generate_catch_exception()!
    const Address thread        (rbp, thread_off         * wordSize);

    const Address r15_save(rbp, r15_off * wordSize);
    const Address r14_save(rbp, r14_off * wordSize);
    const Address r13_save(rbp, r13_off * wordSize);
    const Address r12_save(rbp, r12_off * wordSize);
    const Address rbx_save(rbp, rbx_off * wordSize);

    // stub code
    __ enter();
    __ subptr(rsp, -rsp_after_call_off * wordSize);

    // save register parameters
#ifndef _WIN64
    __ movptr(parameters,   c_rarg5); // parameters
    __ movptr(entry_point,  c_rarg4); // entry_point
#endif

    __ movptr(method,       c_rarg3); // method
    __ movl(result_type,  c_rarg2);   // result type
    __ movptr(result,       c_rarg1); // result
    __ movptr(call_wrapper, c_rarg0); // call wrapper

    // save regs belonging to calling function
    __ movptr(rbx_save, rbx);
    __ movptr(r12_save, r12);
    __ movptr(r13_save, r13);
    __ movptr(r14_save, r14);
    __ movptr(r15_save, r15);

#ifdef _WIN64
    const Address rdi_save(rbp, rdi_off * wordSize);
    const Address rsi_save(rbp, rsi_off * wordSize);

    __ movptr(rsi_save, rsi);
    __ movptr(rdi_save, rdi);
#else
    const Address mxcsr_save(rbp, mxcsr_off * wordSize);
    {
      Label skip_ldmx;
      __ stmxcsr(mxcsr_save);
      __ movl(rax, mxcsr_save);
      __ andl(rax, MXCSR_MASK);    // Only check control and mask bits
      ExternalAddress mxcsr_std(StubRoutines::x86::mxcsr_std());
      __ cmp32(rax, mxcsr_std);
      __ jcc(Assembler::equal, skip_ldmx);
      __ ldmxcsr(mxcsr_std);
      __ bind(skip_ldmx);
    }
#endif

    // Load up thread register
    __ movptr(r15_thread, thread);
    __ reinit_heapbase();

#ifdef ASSERT
    // make sure we have no pending exceptions
    {
      Label L;
      __ cmpptr(Address(r15_thread, Thread::pending_exception_offset()), (int32_t)NULL_WORD);
      __ jcc(Assembler::equal, L);
      __ stop("StubRoutines::call_stub: entered with pending exception");
      __ bind(L);
    }
#endif

    // pass parameters if any
    BLOCK_COMMENT("pass parameters if any");
    Label parameters_done;
    __ movl(c_rarg3, parameter_size);
    __ testl(c_rarg3, c_rarg3);
    __ jcc(Assembler::zero, parameters_done);

    Label loop;
    __ movptr(c_rarg2, parameters);       // parameter pointer
    __ movl(c_rarg1, c_rarg3);            // parameter counter is in c_rarg1
    __ BIND(loop);
    __ movptr(rax, Address(c_rarg2, 0));// get parameter
    __ addptr(c_rarg2, wordSize);       // advance to next parameter
    __ decrementl(c_rarg1);             // decrement counter
    __ push(rax);                       // pass parameter
    __ jcc(Assembler::notZero, loop);

    // call Java function
    __ BIND(parameters_done);
    __ movptr(rbx, method);             // get methodOop
    __ movptr(c_rarg1, entry_point);    // get entry_point
    __ mov(r13, rsp);                   // set sender sp
    BLOCK_COMMENT("call Java function");
    __ call(c_rarg1);

    BLOCK_COMMENT("call_stub_return_address:");
    return_address = __ pc();

    // store result depending on type (everything that is not
    // T_OBJECT, T_LONG, T_FLOAT or T_DOUBLE is treated as T_INT)
    __ movptr(c_rarg0, result);
    Label is_long, is_float, is_double, exit;
    __ movl(c_rarg1, result_type);
    __ cmpl(c_rarg1, T_OBJECT);
    __ jcc(Assembler::equal, is_long);
    __ cmpl(c_rarg1, T_LONG);
    __ jcc(Assembler::equal, is_long);
    __ cmpl(c_rarg1, T_FLOAT);
    __ jcc(Assembler::equal, is_float);
    __ cmpl(c_rarg1, T_DOUBLE);
    __ jcc(Assembler::equal, is_double);

    // handle T_INT case
    __ movl(Address(c_rarg0, 0), rax);

    __ BIND(exit);

    // pop parameters
    __ lea(rsp, rsp_after_call);

#ifdef ASSERT
    // verify that threads correspond
    {
      Label L, S;
      __ cmpptr(r15_thread, thread);
      __ jcc(Assembler::notEqual, S);
      __ get_thread(rbx);
      __ cmpptr(r15_thread, rbx);
      __ jcc(Assembler::equal, L);
      __ bind(S);
      __ jcc(Assembler::equal, L);
      __ stop("StubRoutines::call_stub: threads must correspond");
      __ bind(L);
    }
#endif

    // restore regs belonging to calling function
    __ movptr(r15, r15_save);
    __ movptr(r14, r14_save);
    __ movptr(r13, r13_save);
    __ movptr(r12, r12_save);
    __ movptr(rbx, rbx_save);

#ifdef _WIN64
    __ movptr(rdi, rdi_save);
    __ movptr(rsi, rsi_save);
#else
    __ ldmxcsr(mxcsr_save);
#endif

    // restore rsp
    __ addptr(rsp, -rsp_after_call_off * wordSize);

    // return
    __ pop(rbp);
    __ ret(0);

    // handle return types different from T_INT
    __ BIND(is_long);
    __ movq(Address(c_rarg0, 0), rax);
    __ jmp(exit);

    __ BIND(is_float);
    __ movflt(Address(c_rarg0, 0), xmm0);
    __ jmp(exit);

    __ BIND(is_double);
    __ movdbl(Address(c_rarg0, 0), xmm0);
    __ jmp(exit);

    return start;
  }

  // Return point for a Java call if there's an exception thrown in
  // Java code.  The exception is caught and transformed into a
  // pending exception stored in JavaThread that can be tested from
  // within the VM.
  //
  // Note: Usually the parameters are removed by the callee. In case
  // of an exception crossing an activation frame boundary, that is
  // not the case if the callee is compiled code => need to setup the
  // rsp.
  //
  // rax: exception oop

  address generate_catch_exception() {
    StubCodeMark mark(this, "StubRoutines", "catch_exception");
    address start = __ pc();

    // same as in generate_call_stub():
    const Address rsp_after_call(rbp, rsp_after_call_off * wordSize);
    const Address thread        (rbp, thread_off         * wordSize);

#ifdef ASSERT
    // verify that threads correspond
    {
      Label L, S;
      __ cmpptr(r15_thread, thread);
      __ jcc(Assembler::notEqual, S);
      __ get_thread(rbx);
      __ cmpptr(r15_thread, rbx);
      __ jcc(Assembler::equal, L);
      __ bind(S);
      __ stop("StubRoutines::catch_exception: threads must correspond");
      __ bind(L);
    }
#endif

    // set pending exception
    __ verify_oop(rax);

    __ movptr(Address(r15_thread, Thread::pending_exception_offset()), rax);
    __ lea(rscratch1, ExternalAddress((address)__FILE__));
    __ movptr(Address(r15_thread, Thread::exception_file_offset()), rscratch1);
    __ movl(Address(r15_thread, Thread::exception_line_offset()), (int)  __LINE__);

    // complete return to VM
    assert(StubRoutines::_call_stub_return_address != NULL,
           "_call_stub_return_address must have been generated before");
    __ jump(RuntimeAddress(StubRoutines::_call_stub_return_address));

    return start;
  }

  // Continuation point for runtime calls returning with a pending
  // exception.  The pending exception check happened in the runtime
  // or native call stub.  The pending exception in Thread is
  // converted into a Java-level exception.
  //
  // Contract with Java-level exception handlers:
  // rax: exception
  // rdx: throwing pc
  //
  // NOTE: At entry of this stub, exception-pc must be on stack !!

  address generate_forward_exception() {
    StubCodeMark mark(this, "StubRoutines", "forward exception");
    address start = __ pc();

    // Upon entry, the sp points to the return address returning into
    // Java (interpreted or compiled) code; i.e., the return address
    // becomes the throwing pc.
    //
    // Arguments pushed before the runtime call are still on the stack
    // but the exception handler will reset the stack pointer ->
    // ignore them.  A potential result in registers can be ignored as
    // well.

#ifdef ASSERT
    // make sure this code is only executed if there is a pending exception
    {
      Label L;
      __ cmpptr(Address(r15_thread, Thread::pending_exception_offset()), (int32_t) NULL);
      __ jcc(Assembler::notEqual, L);
      __ stop("StubRoutines::forward exception: no pending exception (1)");
      __ bind(L);
    }
#endif

    // compute exception handler into rbx
    __ movptr(c_rarg0, Address(rsp, 0));
    BLOCK_COMMENT("call exception_handler_for_return_address");
    __ call_VM_leaf(CAST_FROM_FN_PTR(address,
                         SharedRuntime::exception_handler_for_return_address),
                    r15_thread, c_rarg0);
    __ mov(rbx, rax);

    // setup rax & rdx, remove return address & clear pending exception
    __ pop(rdx);
    __ movptr(rax, Address(r15_thread, Thread::pending_exception_offset()));
    __ movptr(Address(r15_thread, Thread::pending_exception_offset()), (int32_t)NULL_WORD);

#ifdef ASSERT
    // make sure exception is set
    {
      Label L;
      __ testptr(rax, rax);
      __ jcc(Assembler::notEqual, L);
      __ stop("StubRoutines::forward exception: no pending exception (2)");
      __ bind(L);
    }
#endif

    // continue at exception handler (return address removed)
    // rax: exception
    // rbx: exception handler
    // rdx: throwing pc
    __ verify_oop(rax);
    __ jmp(rbx);

    return start;
  }

  // Support for jint atomic::xchg(jint exchange_value, volatile jint* dest)
  //
  // Arguments :
  //    c_rarg0: exchange_value
  //    c_rarg0: dest
  //
  // Result:
  //    *dest <- ex, return (orig *dest)
  address generate_atomic_xchg() {
    StubCodeMark mark(this, "StubRoutines", "atomic_xchg");
    address start = __ pc();

    __ movl(rax, c_rarg0); // Copy to eax we need a return value anyhow
    __ xchgl(rax, Address(c_rarg1, 0)); // automatic LOCK
    __ ret(0);

    return start;
  }

  // Support for intptr_t atomic::xchg_ptr(intptr_t exchange_value, volatile intptr_t* dest)
  //
  // Arguments :
  //    c_rarg0: exchange_value
  //    c_rarg1: dest
  //
  // Result:
  //    *dest <- ex, return (orig *dest)
  address generate_atomic_xchg_ptr() {
    StubCodeMark mark(this, "StubRoutines", "atomic_xchg_ptr");
    address start = __ pc();

    __ movptr(rax, c_rarg0); // Copy to eax we need a return value anyhow
    __ xchgptr(rax, Address(c_rarg1, 0)); // automatic LOCK
    __ ret(0);

    return start;
  }

  // Support for jint atomic::atomic_cmpxchg(jint exchange_value, volatile jint* dest,
  //                                         jint compare_value)
  //
  // Arguments :
  //    c_rarg0: exchange_value
  //    c_rarg1: dest
  //    c_rarg2: compare_value
  //
  // Result:
  //    if ( compare_value == *dest ) {
  //       *dest = exchange_value
  //       return compare_value;
  //    else
  //       return *dest;
  address generate_atomic_cmpxchg() {
    StubCodeMark mark(this, "StubRoutines", "atomic_cmpxchg");
    address start = __ pc();

    __ movl(rax, c_rarg2);
   if ( os::is_MP() ) __ lock();
    __ cmpxchgl(c_rarg0, Address(c_rarg1, 0));
    __ ret(0);

    return start;
  }

  // Support for jint atomic::atomic_cmpxchg_long(jlong exchange_value,
  //                                             volatile jlong* dest,
  //                                             jlong compare_value)
  // Arguments :
  //    c_rarg0: exchange_value
  //    c_rarg1: dest
  //    c_rarg2: compare_value
  //
  // Result:
  //    if ( compare_value == *dest ) {
  //       *dest = exchange_value
  //       return compare_value;
  //    else
  //       return *dest;
  address generate_atomic_cmpxchg_long() {
    StubCodeMark mark(this, "StubRoutines", "atomic_cmpxchg_long");
    address start = __ pc();

    __ movq(rax, c_rarg2);
   if ( os::is_MP() ) __ lock();
    __ cmpxchgq(c_rarg0, Address(c_rarg1, 0));
    __ ret(0);

    return start;
  }

  // Support for jint atomic::add(jint add_value, volatile jint* dest)
  //
  // Arguments :
  //    c_rarg0: add_value
  //    c_rarg1: dest
  //
  // Result:
  //    *dest += add_value
  //    return *dest;
  address generate_atomic_add() {
    StubCodeMark mark(this, "StubRoutines", "atomic_add");
    address start = __ pc();

    __ movl(rax, c_rarg0);
   if ( os::is_MP() ) __ lock();
    __ xaddl(Address(c_rarg1, 0), c_rarg0);
    __ addl(rax, c_rarg0);
    __ ret(0);

    return start;
  }

  // Support for intptr_t atomic::add_ptr(intptr_t add_value, volatile intptr_t* dest)
  //
  // Arguments :
  //    c_rarg0: add_value
  //    c_rarg1: dest
  //
  // Result:
  //    *dest += add_value
  //    return *dest;
  address generate_atomic_add_ptr() {
    StubCodeMark mark(this, "StubRoutines", "atomic_add_ptr");
    address start = __ pc();

    __ movptr(rax, c_rarg0); // Copy to eax we need a return value anyhow
   if ( os::is_MP() ) __ lock();
    __ xaddptr(Address(c_rarg1, 0), c_rarg0);
    __ addptr(rax, c_rarg0);
    __ ret(0);

    return start;
  }

  // Support for intptr_t OrderAccess::fence()
  //
  // Arguments :
  //
  // Result:
  address generate_orderaccess_fence() {
    StubCodeMark mark(this, "StubRoutines", "orderaccess_fence");
    address start = __ pc();
    __ membar(Assembler::StoreLoad);
    __ ret(0);

    return start;
  }

  // Support for intptr_t get_previous_fp()
  //
  // This routine is used to find the previous frame pointer for the
  // caller (current_frame_guess). This is used as part of debugging
  // ps() is seemingly lost trying to find frames.
  // This code assumes that caller current_frame_guess) has a frame.
  address generate_get_previous_fp() {
    StubCodeMark mark(this, "StubRoutines", "get_previous_fp");
    const Address old_fp(rbp, 0);
    const Address older_fp(rax, 0);
    address start = __ pc();

    __ enter();
    __ movptr(rax, old_fp); // callers fp
    __ movptr(rax, older_fp); // the frame for ps()
    __ pop(rbp);
    __ ret(0);

    return start;
  }

  //----------------------------------------------------------------------------------------------------
  // Support for void verify_mxcsr()
  //
  // This routine is used with -Xcheck:jni to verify that native
  // JNI code does not return to Java code without restoring the
  // MXCSR register to our expected state.

  address generate_verify_mxcsr() {
    StubCodeMark mark(this, "StubRoutines", "verify_mxcsr");
    address start = __ pc();

    const Address mxcsr_save(rsp, 0);

    if (CheckJNICalls) {
      Label ok_ret;
      __ push(rax);
      __ subptr(rsp, wordSize);      // allocate a temp location
      __ stmxcsr(mxcsr_save);
      __ movl(rax, mxcsr_save);
      __ andl(rax, MXCSR_MASK);    // Only check control and mask bits
      __ cmpl(rax, *(int *)(StubRoutines::x86::mxcsr_std()));
      __ jcc(Assembler::equal, ok_ret);

      __ warn("MXCSR changed by native JNI code, use -XX:+RestoreMXCSROnJNICall");

      __ ldmxcsr(ExternalAddress(StubRoutines::x86::mxcsr_std()));

      __ bind(ok_ret);
      __ addptr(rsp, wordSize);
      __ pop(rax);
    }

    __ ret(0);

    return start;
  }

  address generate_f2i_fixup() {
    StubCodeMark mark(this, "StubRoutines", "f2i_fixup");
    Address inout(rsp, 5 * wordSize); // return address + 4 saves

    address start = __ pc();

    Label L;

    __ push(rax);
    __ push(c_rarg3);
    __ push(c_rarg2);
    __ push(c_rarg1);

    __ movl(rax, 0x7f800000);
    __ xorl(c_rarg3, c_rarg3);
    __ movl(c_rarg2, inout);
    __ movl(c_rarg1, c_rarg2);
    __ andl(c_rarg1, 0x7fffffff);
    __ cmpl(rax, c_rarg1); // NaN? -> 0
    __ jcc(Assembler::negative, L);
    __ testl(c_rarg2, c_rarg2); // signed ? min_jint : max_jint
    __ movl(c_rarg3, 0x80000000);
    __ movl(rax, 0x7fffffff);
    __ cmovl(Assembler::positive, c_rarg3, rax);

    __ bind(L);
    __ movptr(inout, c_rarg3);

    __ pop(c_rarg1);
    __ pop(c_rarg2);
    __ pop(c_rarg3);
    __ pop(rax);

    __ ret(0);

    return start;
  }

  address generate_f2l_fixup() {
    StubCodeMark mark(this, "StubRoutines", "f2l_fixup");
    Address inout(rsp, 5 * wordSize); // return address + 4 saves
    address start = __ pc();

    Label L;

    __ push(rax);
    __ push(c_rarg3);
    __ push(c_rarg2);
    __ push(c_rarg1);

    __ movl(rax, 0x7f800000);
    __ xorl(c_rarg3, c_rarg3);
    __ movl(c_rarg2, inout);
    __ movl(c_rarg1, c_rarg2);
    __ andl(c_rarg1, 0x7fffffff);
    __ cmpl(rax, c_rarg1); // NaN? -> 0
    __ jcc(Assembler::negative, L);
    __ testl(c_rarg2, c_rarg2); // signed ? min_jlong : max_jlong
    __ mov64(c_rarg3, 0x8000000000000000);
    __ mov64(rax, 0x7fffffffffffffff);
    __ cmov(Assembler::positive, c_rarg3, rax);

    __ bind(L);
    __ movptr(inout, c_rarg3);

    __ pop(c_rarg1);
    __ pop(c_rarg2);
    __ pop(c_rarg3);
    __ pop(rax);

    __ ret(0);

    return start;
  }

  address generate_d2i_fixup() {
    StubCodeMark mark(this, "StubRoutines", "d2i_fixup");
    Address inout(rsp, 6 * wordSize); // return address + 5 saves

    address start = __ pc();

    Label L;

    __ push(rax);
    __ push(c_rarg3);
    __ push(c_rarg2);
    __ push(c_rarg1);
    __ push(c_rarg0);

    __ movl(rax, 0x7ff00000);
    __ movq(c_rarg2, inout);
    __ movl(c_rarg3, c_rarg2);
    __ mov(c_rarg1, c_rarg2);
    __ mov(c_rarg0, c_rarg2);
    __ negl(c_rarg3);
    __ shrptr(c_rarg1, 0x20);
    __ orl(c_rarg3, c_rarg2);
    __ andl(c_rarg1, 0x7fffffff);
    __ xorl(c_rarg2, c_rarg2);
    __ shrl(c_rarg3, 0x1f);
    __ orl(c_rarg1, c_rarg3);
    __ cmpl(rax, c_rarg1);
    __ jcc(Assembler::negative, L); // NaN -> 0
    __ testptr(c_rarg0, c_rarg0); // signed ? min_jint : max_jint
    __ movl(c_rarg2, 0x80000000);
    __ movl(rax, 0x7fffffff);
    __ cmov(Assembler::positive, c_rarg2, rax);

    __ bind(L);
    __ movptr(inout, c_rarg2);

    __ pop(c_rarg0);
    __ pop(c_rarg1);
    __ pop(c_rarg2);
    __ pop(c_rarg3);
    __ pop(rax);

    __ ret(0);

    return start;
  }

  address generate_d2l_fixup() {
    StubCodeMark mark(this, "StubRoutines", "d2l_fixup");
    Address inout(rsp, 6 * wordSize); // return address + 5 saves

    address start = __ pc();

    Label L;

    __ push(rax);
    __ push(c_rarg3);
    __ push(c_rarg2);
    __ push(c_rarg1);
    __ push(c_rarg0);

    __ movl(rax, 0x7ff00000);
    __ movq(c_rarg2, inout);
    __ movl(c_rarg3, c_rarg2);
    __ mov(c_rarg1, c_rarg2);
    __ mov(c_rarg0, c_rarg2);
    __ negl(c_rarg3);
    __ shrptr(c_rarg1, 0x20);
    __ orl(c_rarg3, c_rarg2);
    __ andl(c_rarg1, 0x7fffffff);
    __ xorl(c_rarg2, c_rarg2);
    __ shrl(c_rarg3, 0x1f);
    __ orl(c_rarg1, c_rarg3);
    __ cmpl(rax, c_rarg1);
    __ jcc(Assembler::negative, L); // NaN -> 0
    __ testq(c_rarg0, c_rarg0); // signed ? min_jlong : max_jlong
    __ mov64(c_rarg2, 0x8000000000000000);
    __ mov64(rax, 0x7fffffffffffffff);
    __ cmovq(Assembler::positive, c_rarg2, rax);

    __ bind(L);
    __ movq(inout, c_rarg2);

    __ pop(c_rarg0);
    __ pop(c_rarg1);
    __ pop(c_rarg2);
    __ pop(c_rarg3);
    __ pop(rax);

    __ ret(0);

    return start;
  }

  address generate_fp_mask(const char *stub_name, int64_t mask) {
    __ align(CodeEntryAlignment);
    StubCodeMark mark(this, "StubRoutines", stub_name);
    address start = __ pc();

    __ emit_data64( mask, relocInfo::none );
    __ emit_data64( mask, relocInfo::none );

    return start;
  }

  // The following routine generates a subroutine to throw an
  // asynchronous UnknownError when an unsafe access gets a fault that
  // could not be reasonably prevented by the programmer.  (Example:
  // SIGBUS/OBJERR.)
  address generate_handler_for_unsafe_access() {
    StubCodeMark mark(this, "StubRoutines", "handler_for_unsafe_access");
    address start = __ pc();

    __ push(0);                       // hole for return address-to-be
    __ pusha();                       // push registers
    Address next_pc(rsp, RegisterImpl::number_of_registers * BytesPerWord);

    __ subptr(rsp, frame::arg_reg_save_area_bytes);
    BLOCK_COMMENT("call handle_unsafe_access");
    __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, handle_unsafe_access)));
    __ addptr(rsp, frame::arg_reg_save_area_bytes);

    __ movptr(next_pc, rax);          // stuff next address
    __ popa();
    __ ret(0);                        // jump to next address

    return start;
  }

  // Non-destructive plausibility checks for oops
  //
  // Arguments:
  //    all args on stack!
  //
  // Stack after saving c_rarg3:
  //    [tos + 0]: saved c_rarg3
  //    [tos + 1]: saved c_rarg2
  //    [tos + 2]: saved r12 (several TemplateTable methods use it)
  //    [tos + 3]: saved flags
  //    [tos + 4]: return address
  //  * [tos + 5]: error message (char*)
  //  * [tos + 6]: object to verify (oop)
  //  * [tos + 7]: saved rax - saved by caller and bashed
  //  * [tos + 8]: saved r10 (rscratch1) - saved by caller
  //  * = popped on exit
  address generate_verify_oop() {
    StubCodeMark mark(this, "StubRoutines", "verify_oop");
    address start = __ pc();

    Label exit, error;

    __ pushf();
    __ incrementl(ExternalAddress((address) StubRoutines::verify_oop_count_addr()));

    __ push(r12);

    // save c_rarg2 and c_rarg3
    __ push(c_rarg2);
    __ push(c_rarg3);

    enum {
           // After previous pushes.
           oop_to_verify = 6 * wordSize,
           saved_rax     = 7 * wordSize,
           saved_r10     = 8 * wordSize,

           // Before the call to MacroAssembler::debug(), see below.
           return_addr   = 16 * wordSize,
           error_msg     = 17 * wordSize
    };

    // get object
    __ movptr(rax, Address(rsp, oop_to_verify));

    // make sure object is 'reasonable'
    __ testptr(rax, rax);
    __ jcc(Assembler::zero, exit); // if obj is NULL it is OK
    // Check if the oop is in the right area of memory
    __ movptr(c_rarg2, rax);
    __ movptr(c_rarg3, (intptr_t) Universe::verify_oop_mask());
    __ andptr(c_rarg2, c_rarg3);
    __ movptr(c_rarg3, (intptr_t) Universe::verify_oop_bits());
    __ cmpptr(c_rarg2, c_rarg3);
    __ jcc(Assembler::notZero, error);

    // set r12 to heapbase for load_klass()
    __ reinit_heapbase();

    // make sure klass is 'reasonable'
    __ load_klass(rax, rax);  // get klass
    __ testptr(rax, rax);
    __ jcc(Assembler::zero, error); // if klass is NULL it is broken
    // Check if the klass is in the right area of memory
    __ mov(c_rarg2, rax);
    __ movptr(c_rarg3, (intptr_t) Universe::verify_klass_mask());
    __ andptr(c_rarg2, c_rarg3);
    __ movptr(c_rarg3, (intptr_t) Universe::verify_klass_bits());
    __ cmpptr(c_rarg2, c_rarg3);
    __ jcc(Assembler::notZero, error);

    // make sure klass' klass is 'reasonable'
    __ load_klass(rax, rax);
    __ testptr(rax, rax);
    __ jcc(Assembler::zero, error); // if klass' klass is NULL it is broken
    // Check if the klass' klass is in the right area of memory
    __ movptr(c_rarg3, (intptr_t) Universe::verify_klass_mask());
    __ andptr(rax, c_rarg3);
    __ movptr(c_rarg3, (intptr_t) Universe::verify_klass_bits());
    __ cmpptr(rax, c_rarg3);
    __ jcc(Assembler::notZero, error);

    // return if everything seems ok
    __ bind(exit);
    __ movptr(rax, Address(rsp, saved_rax));     // get saved rax back
    __ movptr(rscratch1, Address(rsp, saved_r10)); // get saved r10 back
    __ pop(c_rarg3);                             // restore c_rarg3
    __ pop(c_rarg2);                             // restore c_rarg2
    __ pop(r12);                                 // restore r12
    __ popf();                                   // restore flags
    __ ret(4 * wordSize);                        // pop caller saved stuff

    // handle errors
    __ bind(error);
    __ movptr(rax, Address(rsp, saved_rax));     // get saved rax back
    __ movptr(rscratch1, Address(rsp, saved_r10)); // get saved r10 back
    __ pop(c_rarg3);                             // get saved c_rarg3 back
    __ pop(c_rarg2);                             // get saved c_rarg2 back
    __ pop(r12);                                 // get saved r12 back
    __ popf();                                   // get saved flags off stack --
                                                 // will be ignored

    __ pusha();                                  // push registers
                                                 // (rip is already
                                                 // already pushed)
    // debug(char* msg, int64_t pc, int64_t regs[])
    // We've popped the registers we'd saved (c_rarg3, c_rarg2 and flags), and
    // pushed all the registers, so now the stack looks like:
    //     [tos +  0] 16 saved registers
    //     [tos + 16] return address
    //   * [tos + 17] error message (char*)
    //   * [tos + 18] object to verify (oop)
    //   * [tos + 19] saved rax - saved by caller and bashed
    //   * [tos + 20] saved r10 (rscratch1) - saved by caller
    //   * = popped on exit

    __ movptr(c_rarg0, Address(rsp, error_msg));    // pass address of error message
    __ movptr(c_rarg1, Address(rsp, return_addr));  // pass return address
    __ movq(c_rarg2, rsp);                          // pass address of regs on stack
    __ mov(r12, rsp);                               // remember rsp
    __ subptr(rsp, frame::arg_reg_save_area_bytes); // windows
    __ andptr(rsp, -16);                            // align stack as required by ABI
    BLOCK_COMMENT("call MacroAssembler::debug");
    __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, MacroAssembler::debug64)));
    __ mov(rsp, r12);                               // restore rsp
    __ popa();                                      // pop registers (includes r12)
    __ ret(4 * wordSize);                           // pop caller saved stuff

    return start;
  }

  static address disjoint_byte_copy_entry;
  static address disjoint_short_copy_entry;
  static address disjoint_int_copy_entry;
  static address disjoint_long_copy_entry;
  static address disjoint_oop_copy_entry;

  static address byte_copy_entry;
  static address short_copy_entry;
  static address int_copy_entry;
  static address long_copy_entry;
  static address oop_copy_entry;

  static address checkcast_copy_entry;

  //
  // Verify that a register contains clean 32-bits positive value
  // (high 32-bits are 0) so it could be used in 64-bits shifts.
  //
  //  Input:
  //    Rint  -  32-bits value
  //    Rtmp  -  scratch
  //
  void assert_clean_int(Register Rint, Register Rtmp) {
#ifdef ASSERT
    Label L;
    assert_different_registers(Rtmp, Rint);
    __ movslq(Rtmp, Rint);
    __ cmpq(Rtmp, Rint);
    __ jcc(Assembler::equal, L);
    __ stop("high 32-bits of int value are not 0");
    __ bind(L);
#endif
  }

  //  Generate overlap test for array copy stubs
  //
  //  Input:
  //     c_rarg0 - from
  //     c_rarg1 - to
  //     c_rarg2 - element count
  //
  //  Output:
  //     rax   - &from[element count - 1]
  //
  void array_overlap_test(address no_overlap_target, Address::ScaleFactor sf) {
    assert(no_overlap_target != NULL, "must be generated");
    array_overlap_test(no_overlap_target, NULL, sf);
  }
  void array_overlap_test(Label& L_no_overlap, Address::ScaleFactor sf) {
    array_overlap_test(NULL, &L_no_overlap, sf);
  }
  void array_overlap_test(address no_overlap_target, Label* NOLp, Address::ScaleFactor sf) {
    const Register from     = c_rarg0;
    const Register to       = c_rarg1;
    const Register count    = c_rarg2;
    const Register end_from = rax;

    __ cmpptr(to, from);
    __ lea(end_from, Address(from, count, sf, 0));
    if (NOLp == NULL) {
      ExternalAddress no_overlap(no_overlap_target);
      __ jump_cc(Assembler::belowEqual, no_overlap);
      __ cmpptr(to, end_from);
      __ jump_cc(Assembler::aboveEqual, no_overlap);
    } else {
      __ jcc(Assembler::belowEqual, (*NOLp));
      __ cmpptr(to, end_from);
      __ jcc(Assembler::aboveEqual, (*NOLp));
    }
  }

  // Shuffle first three arg regs on Windows into Linux/Solaris locations.
  //
  // Outputs:
  //    rdi - rcx
  //    rsi - rdx
  //    rdx - r8
  //    rcx - r9
  //
  // Registers r9 and r10 are used to save rdi and rsi on Windows, which latter
  // are non-volatile.  r9 and r10 should not be used by the caller.
  //
  void setup_arg_regs(int nargs = 3) {
    const Register saved_rdi = r9;
    const Register saved_rsi = r10;
    assert(nargs == 3 || nargs == 4, "else fix");
#ifdef _WIN64
    assert(c_rarg0 == rcx && c_rarg1 == rdx && c_rarg2 == r8 && c_rarg3 == r9,
           "unexpected argument registers");
    if (nargs >= 4)
      __ mov(rax, r9);  // r9 is also saved_rdi
    __ movptr(saved_rdi, rdi);
    __ movptr(saved_rsi, rsi);
    __ mov(rdi, rcx); // c_rarg0
    __ mov(rsi, rdx); // c_rarg1
    __ mov(rdx, r8);  // c_rarg2
    if (nargs >= 4)
      __ mov(rcx, rax); // c_rarg3 (via rax)
#else
    assert(c_rarg0 == rdi && c_rarg1 == rsi && c_rarg2 == rdx && c_rarg3 == rcx,
           "unexpected argument registers");
#endif
  }

  void restore_arg_regs() {
    const Register saved_rdi = r9;
    const Register saved_rsi = r10;
#ifdef _WIN64
    __ movptr(rdi, saved_rdi);
    __ movptr(rsi, saved_rsi);
#endif
  }

  // Generate code for an array write pre barrier
  //
  //     addr    -  starting address
  //     count    -  element count
  //
  //     Destroy no registers!
  //
  void  gen_write_ref_array_pre_barrier(Register addr, Register count) {
    BarrierSet* bs = Universe::heap()->barrier_set();
    switch (bs->kind()) {
      case BarrierSet::G1SATBCT:
      case BarrierSet::G1SATBCTLogging:
        {
          __ pusha();                      // push registers
          if (count == c_rarg0) {
            if (addr == c_rarg1) {
              // exactly backwards!!
              __ xchgptr(c_rarg1, c_rarg0);
            } else {
              __ movptr(c_rarg1, count);
              __ movptr(c_rarg0, addr);
            }

          } else {
            __ movptr(c_rarg0, addr);
            __ movptr(c_rarg1, count);
          }
          __ call_VM_leaf(CAST_FROM_FN_PTR(address, BarrierSet::static_write_ref_array_pre), 2);
          __ popa();
        }
        break;
      case BarrierSet::CardTableModRef:
      case BarrierSet::CardTableExtension:
      case BarrierSet::ModRef:
        break;
      default:
        ShouldNotReachHere();

    }
  }

  //
  // Generate code for an array write post barrier
  //
  //  Input:
  //     start    - register containing starting address of destination array
  //     end      - register containing ending address of destination array
  //     scratch  - scratch register
  //
  //  The input registers are overwritten.
  //  The ending address is inclusive.
  void  gen_write_ref_array_post_barrier(Register start, Register end, Register scratch) {
    assert_different_registers(start, end, scratch);
    BarrierSet* bs = Universe::heap()->barrier_set();
    switch (bs->kind()) {
      case BarrierSet::G1SATBCT:
      case BarrierSet::G1SATBCTLogging:

        {
          __ pusha();                      // push registers (overkill)
          // must compute element count unless barrier set interface is changed (other platforms supply count)
          assert_different_registers(start, end, scratch);
          __ lea(scratch, Address(end, BytesPerHeapOop));
          __ subptr(scratch, start);               // subtract start to get #bytes
          __ shrptr(scratch, LogBytesPerHeapOop);  // convert to element count
          __ mov(c_rarg0, start);
          __ mov(c_rarg1, scratch);
          __ call_VM_leaf(CAST_FROM_FN_PTR(address, BarrierSet::static_write_ref_array_post), 2);
          __ popa();
        }
        break;
      case BarrierSet::CardTableModRef:
      case BarrierSet::CardTableExtension:
        {
          CardTableModRefBS* ct = (CardTableModRefBS*)bs;
          assert(sizeof(*ct->byte_map_base) == sizeof(jbyte), "adjust this code");

          Label L_loop;

           __ shrptr(start, CardTableModRefBS::card_shift);
           __ addptr(end, BytesPerHeapOop);
           __ shrptr(end, CardTableModRefBS::card_shift);
           __ subptr(end, start); // number of bytes to copy

          intptr_t disp = (intptr_t) ct->byte_map_base;
          if (__ is_simm32(disp)) {
            Address cardtable(noreg, noreg, Address::no_scale, disp);
            __ lea(scratch, cardtable);
          } else {
            ExternalAddress cardtable((address)disp);
            __ lea(scratch, cardtable);
          }

          const Register count = end; // 'end' register contains bytes count now
          __ addptr(start, scratch);
        __ BIND(L_loop);
          __ movb(Address(start, count, Address::times_1), 0);
          __ decrement(count);
          __ jcc(Assembler::greaterEqual, L_loop);
        }
        break;
      default:
        ShouldNotReachHere();

    }
  }


  // Copy big chunks forward
  //
  // Inputs:
  //   end_from     - source arrays end address
  //   end_to       - destination array end address
  //   qword_count  - 64-bits element count, negative
  //   to           - scratch
  //   L_copy_32_bytes - entry label
  //   L_copy_8_bytes  - exit  label
  //
  void copy_32_bytes_forward(Register end_from, Register end_to,
                             Register qword_count, Register to,
                             Label& L_copy_32_bytes, Label& L_copy_8_bytes) {
    DEBUG_ONLY(__ stop("enter at entry label, not here"));
    Label L_loop;
    __ align(OptoLoopAlignment);
  __ BIND(L_loop);
    if(UseUnalignedLoadStores) {
      __ movdqu(xmm0, Address(end_from, qword_count, Address::times_8, -24));
      __ movdqu(Address(end_to, qword_count, Address::times_8, -24), xmm0);
      __ movdqu(xmm1, Address(end_from, qword_count, Address::times_8, - 8));
      __ movdqu(Address(end_to, qword_count, Address::times_8, - 8), xmm1);

    } else {
      __ movq(to, Address(end_from, qword_count, Address::times_8, -24));
      __ movq(Address(end_to, qword_count, Address::times_8, -24), to);
      __ movq(to, Address(end_from, qword_count, Address::times_8, -16));
      __ movq(Address(end_to, qword_count, Address::times_8, -16), to);
      __ movq(to, Address(end_from, qword_count, Address::times_8, - 8));
      __ movq(Address(end_to, qword_count, Address::times_8, - 8), to);
      __ movq(to, Address(end_from, qword_count, Address::times_8, - 0));
      __ movq(Address(end_to, qword_count, Address::times_8, - 0), to);
    }
  __ BIND(L_copy_32_bytes);
    __ addptr(qword_count, 4);
    __ jcc(Assembler::lessEqual, L_loop);
    __ subptr(qword_count, 4);
    __ jcc(Assembler::less, L_copy_8_bytes); // Copy trailing qwords
  }


  // Copy big chunks backward
  //
  // Inputs:
  //   from         - source arrays address
  //   dest         - destination array address
  //   qword_count  - 64-bits element count
  //   to           - scratch
  //   L_copy_32_bytes - entry label
  //   L_copy_8_bytes  - exit  label
  //
  void copy_32_bytes_backward(Register from, Register dest,
                              Register qword_count, Register to,
                              Label& L_copy_32_bytes, Label& L_copy_8_bytes) {
    DEBUG_ONLY(__ stop("enter at entry label, not here"));
    Label L_loop;
    __ align(OptoLoopAlignment);
  __ BIND(L_loop);
    if(UseUnalignedLoadStores) {
      __ movdqu(xmm0, Address(from, qword_count, Address::times_8, 16));
      __ movdqu(Address(dest, qword_count, Address::times_8, 16), xmm0);
      __ movdqu(xmm1, Address(from, qword_count, Address::times_8,  0));
      __ movdqu(Address(dest, qword_count, Address::times_8,  0), xmm1);

    } else {
      __ movq(to, Address(from, qword_count, Address::times_8, 24));
      __ movq(Address(dest, qword_count, Address::times_8, 24), to);
      __ movq(to, Address(from, qword_count, Address::times_8, 16));
      __ movq(Address(dest, qword_count, Address::times_8, 16), to);
      __ movq(to, Address(from, qword_count, Address::times_8,  8));
      __ movq(Address(dest, qword_count, Address::times_8,  8), to);
      __ movq(to, Address(from, qword_count, Address::times_8,  0));
      __ movq(Address(dest, qword_count, Address::times_8,  0), to);
    }
  __ BIND(L_copy_32_bytes);
    __ subptr(qword_count, 4);
    __ jcc(Assembler::greaterEqual, L_loop);
    __ addptr(qword_count, 4);
    __ jcc(Assembler::greater, L_copy_8_bytes); // Copy trailing qwords
  }


  // Arguments:
  //   aligned - true => Input and output aligned on a HeapWord == 8-byte boundary
  //             ignored
  //   name    - stub name string
  //
  // Inputs:
  //   c_rarg0   - source array address
  //   c_rarg1   - destination array address
  //   c_rarg2   - element count, treated as ssize_t, can be zero
  //
  // If 'from' and/or 'to' are aligned on 4-, 2-, or 1-byte boundaries,
  // we let the hardware handle it.  The one to eight bytes within words,
  // dwords or qwords that span cache line boundaries will still be loaded
  // and stored atomically.
  //
  // Side Effects:
  //   disjoint_byte_copy_entry is set to the no-overlap entry point
  //   used by generate_conjoint_byte_copy().
  //
  address generate_disjoint_byte_copy(bool aligned, const char *name) {
    __ align(CodeEntryAlignment);
    StubCodeMark mark(this, "StubRoutines", name);
    address start = __ pc();

    Label L_copy_32_bytes, L_copy_8_bytes, L_copy_4_bytes, L_copy_2_bytes;
    Label L_copy_byte, L_exit;
    const Register from        = rdi;  // source array address
    const Register to          = rsi;  // destination array address
    const Register count       = rdx;  // elements count
    const Register byte_count  = rcx;
    const Register qword_count = count;
    const Register end_from    = from; // source array end address
    const Register end_to      = to;   // destination array end address
    // End pointers are inclusive, and if count is not zero they point
    // to the last unit copied:  end_to[0] := end_from[0]

    __ enter(); // required for proper stackwalking of RuntimeStub frame
    assert_clean_int(c_rarg2, rax);    // Make sure 'count' is clean int.

    disjoint_byte_copy_entry = __ pc();
    BLOCK_COMMENT("Entry:");
    // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)

    setup_arg_regs(); // from => rdi, to => rsi, count => rdx
                      // r9 and r10 may be used to save non-volatile registers

    // 'from', 'to' and 'count' are now valid
    __ movptr(byte_count, count);
    __ shrptr(count, 3); // count => qword_count

    // Copy from low to high addresses.  Use 'to' as scratch.
    __ lea(end_from, Address(from, qword_count, Address::times_8, -8));
    __ lea(end_to,   Address(to,   qword_count, Address::times_8, -8));
    __ negptr(qword_count); // make the count negative
    __ jmp(L_copy_32_bytes);

    // Copy trailing qwords
  __ BIND(L_copy_8_bytes);
    __ movq(rax, Address(end_from, qword_count, Address::times_8, 8));
    __ movq(Address(end_to, qword_count, Address::times_8, 8), rax);
    __ increment(qword_count);
    __ jcc(Assembler::notZero, L_copy_8_bytes);

    // Check for and copy trailing dword
  __ BIND(L_copy_4_bytes);
    __ testl(byte_count, 4);
    __ jccb(Assembler::zero, L_copy_2_bytes);
    __ movl(rax, Address(end_from, 8));
    __ movl(Address(end_to, 8), rax);

    __ addptr(end_from, 4);
    __ addptr(end_to, 4);

    // Check for and copy trailing word
  __ BIND(L_copy_2_bytes);
    __ testl(byte_count, 2);
    __ jccb(Assembler::zero, L_copy_byte);
    __ movw(rax, Address(end_from, 8));
    __ movw(Address(end_to, 8), rax);

    __ addptr(end_from, 2);
    __ addptr(end_to, 2);

    // Check for and copy trailing byte
  __ BIND(L_copy_byte);
    __ testl(byte_count, 1);
    __ jccb(Assembler::zero, L_exit);
    __ movb(rax, Address(end_from, 8));
    __ movb(Address(end_to, 8), rax);

  __ BIND(L_exit);
    inc_counter_np(SharedRuntime::_jbyte_array_copy_ctr);
    restore_arg_regs();
    __ xorptr(rax, rax); // return 0
    __ leave(); // required for proper stackwalking of RuntimeStub frame
    __ ret(0);

    // Copy in 32-bytes chunks
    copy_32_bytes_forward(end_from, end_to, qword_count, rax, L_copy_32_bytes, L_copy_8_bytes);
    __ jmp(L_copy_4_bytes);

    return start;
  }

  // Arguments:
  //   aligned - true => Input and output aligned on a HeapWord == 8-byte boundary
  //             ignored
  //   name    - stub name string
  //
  // Inputs:
  //   c_rarg0   - source array address
  //   c_rarg1   - destination array address
  //   c_rarg2   - element count, treated as ssize_t, can be zero
  //
  // If 'from' and/or 'to' are aligned on 4-, 2-, or 1-byte boundaries,
  // we let the hardware handle it.  The one to eight bytes within words,
  // dwords or qwords that span cache line boundaries will still be loaded
  // and stored atomically.
  //
  address generate_conjoint_byte_copy(bool aligned, const char *name) {
    __ align(CodeEntryAlignment);
    StubCodeMark mark(this, "StubRoutines", name);
    address start = __ pc();

    Label L_copy_32_bytes, L_copy_8_bytes, L_copy_4_bytes, L_copy_2_bytes;
    const Register from        = rdi;  // source array address
    const Register to          = rsi;  // destination array address
    const Register count       = rdx;  // elements count
    const Register byte_count  = rcx;
    const Register qword_count = count;

    __ enter(); // required for proper stackwalking of RuntimeStub frame
    assert_clean_int(c_rarg2, rax);    // Make sure 'count' is clean int.

    byte_copy_entry = __ pc();
    BLOCK_COMMENT("Entry:");
    // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)

    array_overlap_test(disjoint_byte_copy_entry, Address::times_1);
    setup_arg_regs(); // from => rdi, to => rsi, count => rdx
                      // r9 and r10 may be used to save non-volatile registers

    // 'from', 'to' and 'count' are now valid
    __ movptr(byte_count, count);
    __ shrptr(count, 3);   // count => qword_count

    // Copy from high to low addresses.

    // Check for and copy trailing byte
    __ testl(byte_count, 1);
    __ jcc(Assembler::zero, L_copy_2_bytes);
    __ movb(rax, Address(from, byte_count, Address::times_1, -1));
    __ movb(Address(to, byte_count, Address::times_1, -1), rax);
    __ decrement(byte_count); // Adjust for possible trailing word

    // Check for and copy trailing word
  __ BIND(L_copy_2_bytes);
    __ testl(byte_count, 2);
    __ jcc(Assembler::zero, L_copy_4_bytes);
    __ movw(rax, Address(from, byte_count, Address::times_1, -2));
    __ movw(Address(to, byte_count, Address::times_1, -2), rax);

    // Check for and copy trailing dword
  __ BIND(L_copy_4_bytes);
    __ testl(byte_count, 4);
    __ jcc(Assembler::zero, L_copy_32_bytes);
    __ movl(rax, Address(from, qword_count, Address::times_8));
    __ movl(Address(to, qword_count, Address::times_8), rax);
    __ jmp(L_copy_32_bytes);

    // Copy trailing qwords
  __ BIND(L_copy_8_bytes);
    __ movq(rax, Address(from, qword_count, Address::times_8, -8));
    __ movq(Address(to, qword_count, Address::times_8, -8), rax);
    __ decrement(qword_count);
    __ jcc(Assembler::notZero, L_copy_8_bytes);

    inc_counter_np(SharedRuntime::_jbyte_array_copy_ctr);
    restore_arg_regs();
    __ xorptr(rax, rax); // return 0
    __ leave(); // required for proper stackwalking of RuntimeStub frame
    __ ret(0);

    // Copy in 32-bytes chunks
    copy_32_bytes_backward(from, to, qword_count, rax, L_copy_32_bytes, L_copy_8_bytes);

    inc_counter_np(SharedRuntime::_jbyte_array_copy_ctr);
    restore_arg_regs();
    __ xorptr(rax, rax); // return 0
    __ leave(); // required for proper stackwalking of RuntimeStub frame
    __ ret(0);

    return start;
  }

  // Arguments:
  //   aligned - true => Input and output aligned on a HeapWord == 8-byte boundary
  //             ignored
  //   name    - stub name string
  //
  // Inputs:
  //   c_rarg0   - source array address
  //   c_rarg1   - destination array address
  //   c_rarg2   - element count, treated as ssize_t, can be zero
  //
  // If 'from' and/or 'to' are aligned on 4- or 2-byte boundaries, we
  // let the hardware handle it.  The two or four words within dwords
  // or qwords that span cache line boundaries will still be loaded
  // and stored atomically.
  //
  // Side Effects:
  //   disjoint_short_copy_entry is set to the no-overlap entry point
  //   used by generate_conjoint_short_copy().
  //
  address generate_disjoint_short_copy(bool aligned, const char *name) {
    __ align(CodeEntryAlignment);
    StubCodeMark mark(this, "StubRoutines", name);
    address start = __ pc();

    Label L_copy_32_bytes, L_copy_8_bytes, L_copy_4_bytes,L_copy_2_bytes,L_exit;
    const Register from        = rdi;  // source array address
    const Register to          = rsi;  // destination array address
    const Register count       = rdx;  // elements count
    const Register word_count  = rcx;
    const Register qword_count = count;
    const Register end_from    = from; // source array end address
    const Register end_to      = to;   // destination array end address
    // End pointers are inclusive, and if count is not zero they point
    // to the last unit copied:  end_to[0] := end_from[0]

    __ enter(); // required for proper stackwalking of RuntimeStub frame
    assert_clean_int(c_rarg2, rax);    // Make sure 'count' is clean int.

    disjoint_short_copy_entry = __ pc();
    BLOCK_COMMENT("Entry:");
    // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)

    setup_arg_regs(); // from => rdi, to => rsi, count => rdx
                      // r9 and r10 may be used to save non-volatile registers

    // 'from', 'to' and 'count' are now valid
    __ movptr(word_count, count);
    __ shrptr(count, 2); // count => qword_count

    // Copy from low to high addresses.  Use 'to' as scratch.
    __ lea(end_from, Address(from, qword_count, Address::times_8, -8));
    __ lea(end_to,   Address(to,   qword_count, Address::times_8, -8));
    __ negptr(qword_count);
    __ jmp(L_copy_32_bytes);

    // Copy trailing qwords
  __ BIND(L_copy_8_bytes);
    __ movq(rax, Address(end_from, qword_count, Address::times_8, 8));
    __ movq(Address(end_to, qword_count, Address::times_8, 8), rax);
    __ increment(qword_count);
    __ jcc(Assembler::notZero, L_copy_8_bytes);

    // Original 'dest' is trashed, so we can't use it as a
    // base register for a possible trailing word copy

    // Check for and copy trailing dword
  __ BIND(L_copy_4_bytes);
    __ testl(word_count, 2);
    __ jccb(Assembler::zero, L_copy_2_bytes);
    __ movl(rax, Address(end_from, 8));
    __ movl(Address(end_to, 8), rax);

    __ addptr(end_from, 4);
    __ addptr(end_to, 4);

    // Check for and copy trailing word
  __ BIND(L_copy_2_bytes);
    __ testl(word_count, 1);
    __ jccb(Assembler::zero, L_exit);
    __ movw(rax, Address(end_from, 8));
    __ movw(Address(end_to, 8), rax);

  __ BIND(L_exit);
    inc_counter_np(SharedRuntime::_jshort_array_copy_ctr);
    restore_arg_regs();
    __ xorptr(rax, rax); // return 0
    __ leave(); // required for proper stackwalking of RuntimeStub frame
    __ ret(0);

    // Copy in 32-bytes chunks
    copy_32_bytes_forward(end_from, end_to, qword_count, rax, L_copy_32_bytes, L_copy_8_bytes);
    __ jmp(L_copy_4_bytes);

    return start;
  }

  address generate_fill(BasicType t, bool aligned, const char *name) {
    __ align(CodeEntryAlignment);
    StubCodeMark mark(this, "StubRoutines", name);
    address start = __ pc();

    BLOCK_COMMENT("Entry:");

    const Register to       = c_rarg0;  // source array address
    const Register value    = c_rarg1;  // value
    const Register count    = c_rarg2;  // elements count

    __ enter(); // required for proper stackwalking of RuntimeStub frame

    __ generate_fill(t, aligned, to, value, count, rax, xmm0);

    __ leave(); // required for proper stackwalking of RuntimeStub frame
    __ ret(0);
    return start;
  }

  // Arguments:
  //   aligned - true => Input and output aligned on a HeapWord == 8-byte boundary
  //             ignored
  //   name    - stub name string
  //
  // Inputs:
  //   c_rarg0   - source array address
  //   c_rarg1   - destination array address
  //   c_rarg2   - element count, treated as ssize_t, can be zero
  //
  // If 'from' and/or 'to' are aligned on 4- or 2-byte boundaries, we
  // let the hardware handle it.  The two or four words within dwords
  // or qwords that span cache line boundaries will still be loaded
  // and stored atomically.
  //
  address generate_conjoint_short_copy(bool aligned, const char *name) {
    __ align(CodeEntryAlignment);
    StubCodeMark mark(this, "StubRoutines", name);
    address start = __ pc();

    Label L_copy_32_bytes, L_copy_8_bytes, L_copy_4_bytes;
    const Register from        = rdi;  // source array address
    const Register to          = rsi;  // destination array address
    const Register count       = rdx;  // elements count
    const Register word_count  = rcx;
    const Register qword_count = count;

    __ enter(); // required for proper stackwalking of RuntimeStub frame
    assert_clean_int(c_rarg2, rax);    // Make sure 'count' is clean int.

    short_copy_entry = __ pc();
    BLOCK_COMMENT("Entry:");
    // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)

    array_overlap_test(disjoint_short_copy_entry, Address::times_2);
    setup_arg_regs(); // from => rdi, to => rsi, count => rdx
                      // r9 and r10 may be used to save non-volatile registers

    // 'from', 'to' and 'count' are now valid
    __ movptr(word_count, count);
    __ shrptr(count, 2); // count => qword_count

    // Copy from high to low addresses.  Use 'to' as scratch.

    // Check for and copy trailing word
    __ testl(word_count, 1);
    __ jccb(Assembler::zero, L_copy_4_bytes);
    __ movw(rax, Address(from, word_count, Address::times_2, -2));
    __ movw(Address(to, word_count, Address::times_2, -2), rax);

    // Check for and copy trailing dword
  __ BIND(L_copy_4_bytes);
    __ testl(word_count, 2);
    __ jcc(Assembler::zero, L_copy_32_bytes);
    __ movl(rax, Address(from, qword_count, Address::times_8));
    __ movl(Address(to, qword_count, Address::times_8), rax);
    __ jmp(L_copy_32_bytes);

    // Copy trailing qwords
  __ BIND(L_copy_8_bytes);
    __ movq(rax, Address(from, qword_count, Address::times_8, -8));
    __ movq(Address(to, qword_count, Address::times_8, -8), rax);
    __ decrement(qword_count);
    __ jcc(Assembler::notZero, L_copy_8_bytes);

    inc_counter_np(SharedRuntime::_jshort_array_copy_ctr);
    restore_arg_regs();
    __ xorptr(rax, rax); // return 0
    __ leave(); // required for proper stackwalking of RuntimeStub frame
    __ ret(0);

    // Copy in 32-bytes chunks
    copy_32_bytes_backward(from, to, qword_count, rax, L_copy_32_bytes, L_copy_8_bytes);

    inc_counter_np(SharedRuntime::_jshort_array_copy_ctr);
    restore_arg_regs();
    __ xorptr(rax, rax); // return 0
    __ leave(); // required for proper stackwalking of RuntimeStub frame
    __ ret(0);

    return start;
  }

  // Arguments:
  //   aligned - true => Input and output aligned on a HeapWord == 8-byte boundary
  //             ignored
  //   is_oop  - true => oop array, so generate store check code
  //   name    - stub name string
  //
  // Inputs:
  //   c_rarg0   - source array address
  //   c_rarg1   - destination array address
  //   c_rarg2   - element count, treated as ssize_t, can be zero
  //
  // If 'from' and/or 'to' are aligned on 4-byte boundaries, we let
  // the hardware handle it.  The two dwords within qwords that span
  // cache line boundaries will still be loaded and stored atomicly.
  //
  // Side Effects:
  //   disjoint_int_copy_entry is set to the no-overlap entry point
  //   used by generate_conjoint_int_oop_copy().
  //
  address generate_disjoint_int_oop_copy(bool aligned, bool is_oop, const char *name) {
    __ align(CodeEntryAlignment);
    StubCodeMark mark(this, "StubRoutines", name);
    address start = __ pc();

    Label L_copy_32_bytes, L_copy_8_bytes, L_copy_4_bytes, L_exit;
    const Register from        = rdi;  // source array address
    const Register to          = rsi;  // destination array address
    const Register count       = rdx;  // elements count
    const Register dword_count = rcx;
    const Register qword_count = count;
    const Register end_from    = from; // source array end address
    const Register end_to      = to;   // destination array end address
    const Register saved_to    = r11;  // saved destination array address
    // End pointers are inclusive, and if count is not zero they point
    // to the last unit copied:  end_to[0] := end_from[0]

    __ enter(); // required for proper stackwalking of RuntimeStub frame
    assert_clean_int(c_rarg2, rax);    // Make sure 'count' is clean int.

    (is_oop ? disjoint_oop_copy_entry : disjoint_int_copy_entry) = __ pc();

    if (is_oop) {
      // no registers are destroyed by this call
      gen_write_ref_array_pre_barrier(/* dest */ c_rarg1, /* count */ c_rarg2);
    }

    BLOCK_COMMENT("Entry:");
    // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)

    setup_arg_regs(); // from => rdi, to => rsi, count => rdx
                      // r9 and r10 may be used to save non-volatile registers

    if (is_oop) {
      __ movq(saved_to, to);
    }

    // 'from', 'to' and 'count' are now valid
    __ movptr(dword_count, count);
    __ shrptr(count, 1); // count => qword_count

    // Copy from low to high addresses.  Use 'to' as scratch.
    __ lea(end_from, Address(from, qword_count, Address::times_8, -8));
    __ lea(end_to,   Address(to,   qword_count, Address::times_8, -8));
    __ negptr(qword_count);
    __ jmp(L_copy_32_bytes);

    // Copy trailing qwords
  __ BIND(L_copy_8_bytes);
    __ movq(rax, Address(end_from, qword_count, Address::times_8, 8));
    __ movq(Address(end_to, qword_count, Address::times_8, 8), rax);
    __ increment(qword_count);
    __ jcc(Assembler::notZero, L_copy_8_bytes);

    // Check for and copy trailing dword
  __ BIND(L_copy_4_bytes);
    __ testl(dword_count, 1); // Only byte test since the value is 0 or 1
    __ jccb(Assembler::zero, L_exit);
    __ movl(rax, Address(end_from, 8));
    __ movl(Address(end_to, 8), rax);

  __ BIND(L_exit);
    if (is_oop) {
      __ leaq(end_to, Address(saved_to, dword_count, Address::times_4, -4));
      gen_write_ref_array_post_barrier(saved_to, end_to, rax);
    }
    inc_counter_np(SharedRuntime::_jint_array_copy_ctr);
    restore_arg_regs();
    __ xorptr(rax, rax); // return 0
    __ leave(); // required for proper stackwalking of RuntimeStub frame
    __ ret(0);

    // Copy 32-bytes chunks
    copy_32_bytes_forward(end_from, end_to, qword_count, rax, L_copy_32_bytes, L_copy_8_bytes);
    __ jmp(L_copy_4_bytes);

    return start;
  }

  // Arguments:
  //   aligned - true => Input and output aligned on a HeapWord == 8-byte boundary
  //             ignored
  //   is_oop  - true => oop array, so generate store check code
  //   name    - stub name string
  //
  // Inputs:
  //   c_rarg0   - source array address
  //   c_rarg1   - destination array address
  //   c_rarg2   - element count, treated as ssize_t, can be zero
  //
  // If 'from' and/or 'to' are aligned on 4-byte boundaries, we let
  // the hardware handle it.  The two dwords within qwords that span
  // cache line boundaries will still be loaded and stored atomicly.
  //
  address generate_conjoint_int_oop_copy(bool aligned, bool is_oop, const char *name) {
    __ align(CodeEntryAlignment);
    StubCodeMark mark(this, "StubRoutines", name);
    address start = __ pc();

    Label L_copy_32_bytes, L_copy_8_bytes, L_copy_2_bytes, L_exit;
    const Register from        = rdi;  // source array address
    const Register to          = rsi;  // destination array address
    const Register count       = rdx;  // elements count
    const Register dword_count = rcx;
    const Register qword_count = count;

    __ enter(); // required for proper stackwalking of RuntimeStub frame
    assert_clean_int(c_rarg2, rax);    // Make sure 'count' is clean int.

    if (is_oop) {
      // no registers are destroyed by this call
      gen_write_ref_array_pre_barrier(/* dest */ c_rarg1, /* count */ c_rarg2);
    }

    (is_oop ? oop_copy_entry : int_copy_entry) = __ pc();
    BLOCK_COMMENT("Entry:");
    // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)

    array_overlap_test(is_oop ? disjoint_oop_copy_entry : disjoint_int_copy_entry,
                       Address::times_4);
    setup_arg_regs(); // from => rdi, to => rsi, count => rdx
                      // r9 and r10 may be used to save non-volatile registers

    assert_clean_int(count, rax); // Make sure 'count' is clean int.
    // 'from', 'to' and 'count' are now valid
    __ movptr(dword_count, count);
    __ shrptr(count, 1); // count => qword_count

    // Copy from high to low addresses.  Use 'to' as scratch.

    // Check for and copy trailing dword
    __ testl(dword_count, 1);
    __ jcc(Assembler::zero, L_copy_32_bytes);
    __ movl(rax, Address(from, dword_count, Address::times_4, -4));
    __ movl(Address(to, dword_count, Address::times_4, -4), rax);
    __ jmp(L_copy_32_bytes);

    // Copy trailing qwords
  __ BIND(L_copy_8_bytes);
    __ movq(rax, Address(from, qword_count, Address::times_8, -8));
    __ movq(Address(to, qword_count, Address::times_8, -8), rax);
    __ decrement(qword_count);
    __ jcc(Assembler::notZero, L_copy_8_bytes);

    inc_counter_np(SharedRuntime::_jint_array_copy_ctr);
    if (is_oop) {
      __ jmp(L_exit);
    }
    restore_arg_regs();
    __ xorptr(rax, rax); // return 0
    __ leave(); // required for proper stackwalking of RuntimeStub frame
    __ ret(0);

    // Copy in 32-bytes chunks
    copy_32_bytes_backward(from, to, qword_count, rax, L_copy_32_bytes, L_copy_8_bytes);

   inc_counter_np(SharedRuntime::_jint_array_copy_ctr);
   __ bind(L_exit);
     if (is_oop) {
       Register end_to = rdx;
       __ leaq(end_to, Address(to, dword_count, Address::times_4, -4));
       gen_write_ref_array_post_barrier(to, end_to, rax);
     }
    restore_arg_regs();
    __ xorptr(rax, rax); // return 0
    __ leave(); // required for proper stackwalking of RuntimeStub frame
    __ ret(0);

    return start;
  }

  // Arguments:
  //   aligned - true => Input and output aligned on a HeapWord boundary == 8 bytes
  //             ignored
  //   is_oop  - true => oop array, so generate store check code
  //   name    - stub name string
  //
  // Inputs:
  //   c_rarg0   - source array address
  //   c_rarg1   - destination array address
  //   c_rarg2   - element count, treated as ssize_t, can be zero
  //
 // Side Effects:
  //   disjoint_oop_copy_entry or disjoint_long_copy_entry is set to the
  //   no-overlap entry point used by generate_conjoint_long_oop_copy().
  //
  address generate_disjoint_long_oop_copy(bool aligned, bool is_oop, const char *name) {
    __ align(CodeEntryAlignment);
    StubCodeMark mark(this, "StubRoutines", name);
    address start = __ pc();

    Label L_copy_32_bytes, L_copy_8_bytes, L_exit;
    const Register from        = rdi;  // source array address
    const Register to          = rsi;  // destination array address
    const Register qword_count = rdx;  // elements count
    const Register end_from    = from; // source array end address
    const Register end_to      = rcx;  // destination array end address
    const Register saved_to    = to;
    // End pointers are inclusive, and if count is not zero they point
    // to the last unit copied:  end_to[0] := end_from[0]

    __ enter(); // required for proper stackwalking of RuntimeStub frame
    // Save no-overlap entry point for generate_conjoint_long_oop_copy()
    assert_clean_int(c_rarg2, rax);    // Make sure 'count' is clean int.

    if (is_oop) {
      disjoint_oop_copy_entry  = __ pc();
      // no registers are destroyed by this call
      gen_write_ref_array_pre_barrier(/* dest */ c_rarg1, /* count */ c_rarg2);
    } else {
      disjoint_long_copy_entry = __ pc();
    }
    BLOCK_COMMENT("Entry:");
    // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)

    setup_arg_regs(); // from => rdi, to => rsi, count => rdx
                      // r9 and r10 may be used to save non-volatile registers

    // 'from', 'to' and 'qword_count' are now valid

    // Copy from low to high addresses.  Use 'to' as scratch.
    __ lea(end_from, Address(from, qword_count, Address::times_8, -8));
    __ lea(end_to,   Address(to,   qword_count, Address::times_8, -8));
    __ negptr(qword_count);
    __ jmp(L_copy_32_bytes);

    // Copy trailing qwords
  __ BIND(L_copy_8_bytes);
    __ movq(rax, Address(end_from, qword_count, Address::times_8, 8));
    __ movq(Address(end_to, qword_count, Address::times_8, 8), rax);
    __ increment(qword_count);
    __ jcc(Assembler::notZero, L_copy_8_bytes);

    if (is_oop) {
      __ jmp(L_exit);
    } else {
      inc_counter_np(SharedRuntime::_jlong_array_copy_ctr);
      restore_arg_regs();
      __ xorptr(rax, rax); // return 0
      __ leave(); // required for proper stackwalking of RuntimeStub frame
      __ ret(0);
    }

    // Copy 64-byte chunks
    copy_32_bytes_forward(end_from, end_to, qword_count, rax, L_copy_32_bytes, L_copy_8_bytes);

    if (is_oop) {
    __ BIND(L_exit);
      gen_write_ref_array_post_barrier(saved_to, end_to, rax);
      inc_counter_np(SharedRuntime::_oop_array_copy_ctr);
    } else {
      inc_counter_np(SharedRuntime::_jlong_array_copy_ctr);
    }
    restore_arg_regs();
    __ xorptr(rax, rax); // return 0
    __ leave(); // required for proper stackwalking of RuntimeStub frame
    __ ret(0);

    return start;
  }

  // Arguments:
  //   aligned - true => Input and output aligned on a HeapWord boundary == 8 bytes
  //             ignored
  //   is_oop  - true => oop array, so generate store check code
  //   name    - stub name string
  //
  // Inputs:
  //   c_rarg0   - source array address
  //   c_rarg1   - destination array address
  //   c_rarg2   - element count, treated as ssize_t, can be zero
  //
  address generate_conjoint_long_oop_copy(bool aligned, bool is_oop, const char *name) {
    __ align(CodeEntryAlignment);
    StubCodeMark mark(this, "StubRoutines", name);
    address start = __ pc();

    Label L_copy_32_bytes, L_copy_8_bytes, L_exit;
    const Register from        = rdi;  // source array address
    const Register to          = rsi;  // destination array address
    const Register qword_count = rdx;  // elements count
    const Register saved_count = rcx;

    __ enter(); // required for proper stackwalking of RuntimeStub frame
    assert_clean_int(c_rarg2, rax);    // Make sure 'count' is clean int.

    address disjoint_copy_entry = NULL;
    if (is_oop) {
      assert(!UseCompressedOops, "shouldn't be called for compressed oops");
      disjoint_copy_entry = disjoint_oop_copy_entry;
      oop_copy_entry  = __ pc();
      array_overlap_test(disjoint_oop_copy_entry, Address::times_8);
    } else {
      disjoint_copy_entry = disjoint_long_copy_entry;
      long_copy_entry = __ pc();
      array_overlap_test(disjoint_long_copy_entry, Address::times_8);
    }
    BLOCK_COMMENT("Entry:");
    // caller can pass a 64-bit byte count here (from Unsafe.copyMemory)

    array_overlap_test(disjoint_copy_entry, Address::times_8);
    setup_arg_regs(); // from => rdi, to => rsi, count => rdx
                      // r9 and r10 may be used to save non-volatile registers

    // 'from', 'to' and 'qword_count' are now valid

    if (is_oop) {
      // Save to and count for store barrier
      __ movptr(saved_count, qword_count);
      // No registers are destroyed by this call
      gen_write_ref_array_pre_barrier(to, saved_count);
    }

    __ jmp(L_copy_32_bytes);

    // Copy trailing qwords
  __ BIND(L_copy_8_bytes);
    __ movq(rax, Address(from, qword_count, Address::times_8, -8));
    __ movq(Address(to, qword_count, Address::times_8, -8), rax);
    __ decrement(qword_count);
    __ jcc(Assembler::notZero, L_copy_8_bytes);

    if (is_oop) {
      __ jmp(L_exit);
    } else {
      inc_counter_np(SharedRuntime::_jlong_array_copy_ctr);
      restore_arg_regs();
      __ xorptr(rax, rax); // return 0
      __ leave(); // required for proper stackwalking of RuntimeStub frame
      __ ret(0);
    }

    // Copy in 32-bytes chunks
    copy_32_bytes_backward(from, to, qword_count, rax, L_copy_32_bytes, L_copy_8_bytes);

    if (is_oop) {
    __ BIND(L_exit);
      __ lea(rcx, Address(to, saved_count, Address::times_8, -8));
      gen_write_ref_array_post_barrier(to, rcx, rax);
      inc_counter_np(SharedRuntime::_oop_array_copy_ctr);
    } else {
      inc_counter_np(SharedRuntime::_jlong_array_copy_ctr);
    }
    restore_arg_regs();
    __ xorptr(rax, rax); // return 0
    __ leave(); // required for proper stackwalking of RuntimeStub frame
    __ ret(0);

    return start;
  }


  // Helper for generating a dynamic type check.
  // Smashes no registers.
  void generate_type_check(Register sub_klass,
                           Register super_check_offset,
                           Register super_klass,
                           Label& L_success) {
    assert_different_registers(sub_klass, super_check_offset, super_klass);

    BLOCK_COMMENT("type_check:");

    Label L_miss;

    __ check_klass_subtype_fast_path(sub_klass, super_klass, noreg,        &L_success, &L_miss, NULL,
                                     super_check_offset);
    __ check_klass_subtype_slow_path(sub_klass, super_klass, noreg, noreg, &L_success, NULL);

    // Fall through on failure!
    __ BIND(L_miss);
  }

  //
  //  Generate checkcasting array copy stub
  //
  //  Input:
  //    c_rarg0   - source array address
  //    c_rarg1   - destination array address
  //    c_rarg2   - element count, treated as ssize_t, can be zero
  //    c_rarg3   - size_t ckoff (super_check_offset)
  // not Win64
  //    c_rarg4   - oop ckval (super_klass)
  // Win64
  //    rsp+40    - oop ckval (super_klass)
  //
  //  Output:
  //    rax ==  0  -  success
  //    rax == -1^K - failure, where K is partial transfer count
  //
  address generate_checkcast_copy(const char *name) {

    Label L_load_element, L_store_element, L_do_card_marks, L_done;

    // Input registers (after setup_arg_regs)
    const Register from        = rdi;   // source array address
    const Register to          = rsi;   // destination array address
    const Register length      = rdx;   // elements count
    const Register ckoff       = rcx;   // super_check_offset
    const Register ckval       = r8;    // super_klass

    // Registers used as temps (r13, r14 are save-on-entry)
    const Register end_from    = from;  // source array end address
    const Register end_to      = r13;   // destination array end address
    const Register count       = rdx;   // -(count_remaining)
    const Register r14_length  = r14;   // saved copy of length
    // End pointers are inclusive, and if length is not zero they point
    // to the last unit copied:  end_to[0] := end_from[0]

    const Register rax_oop    = rax;    // actual oop copied
    const Register r11_klass  = r11;    // oop._klass

    //---------------------------------------------------------------
    // Assembler stub will be used for this call to arraycopy
    // if the two arrays are subtypes of Object[] but the
    // destination array type is not equal to or a supertype
    // of the source type.  Each element must be separately
    // checked.

    __ align(CodeEntryAlignment);
    StubCodeMark mark(this, "StubRoutines", name);
    address start = __ pc();

    __ enter(); // required for proper stackwalking of RuntimeStub frame

#ifdef ASSERT
    // caller guarantees that the arrays really are different
    // otherwise, we would have to make conjoint checks
    { Label L;
      array_overlap_test(L, TIMES_OOP);
      __ stop("checkcast_copy within a single array");
      __ bind(L);
    }
#endif //ASSERT

    setup_arg_regs(4); // from => rdi, to => rsi, length => rdx
                       // ckoff => rcx, ckval => r8
                       // r9 and r10 may be used to save non-volatile registers
#ifdef _WIN64
    // last argument (#4) is on stack on Win64
    __ movptr(ckval, Address(rsp, 6 * wordSize));
#endif

    // Caller of this entry point must set up the argument registers.
    checkcast_copy_entry  = __ pc();
    BLOCK_COMMENT("Entry:");

    // allocate spill slots for r13, r14
    enum {
      saved_r13_offset,
      saved_r14_offset,
      saved_rbp_offset
    };
    __ subptr(rsp, saved_rbp_offset * wordSize);
    __ movptr(Address(rsp, saved_r13_offset * wordSize), r13);
    __ movptr(Address(rsp, saved_r14_offset * wordSize), r14);

    // check that int operands are properly extended to size_t
    assert_clean_int(length, rax);
    assert_clean_int(ckoff, rax);

#ifdef ASSERT
    BLOCK_COMMENT("assert consistent ckoff/ckval");
    // The ckoff and ckval must be mutually consistent,
    // even though caller generates both.
    { Label L;
      int sco_offset = (klassOopDesc::header_size() * HeapWordSize +
                        Klass::super_check_offset_offset_in_bytes());
      __ cmpl(ckoff, Address(ckval, sco_offset));
      __ jcc(Assembler::equal, L);
      __ stop("super_check_offset inconsistent");
      __ bind(L);
    }
#endif //ASSERT

    // Loop-invariant addresses.  They are exclusive end pointers.
    Address end_from_addr(from, length, TIMES_OOP, 0);
    Address   end_to_addr(to,   length, TIMES_OOP, 0);
    // Loop-variant addresses.  They assume post-incremented count < 0.
    Address from_element_addr(end_from, count, TIMES_OOP, 0);
    Address   to_element_addr(end_to,   count, TIMES_OOP, 0);

    gen_write_ref_array_pre_barrier(to, count);

    // Copy from low to high addresses, indexed from the end of each array.
    __ lea(end_from, end_from_addr);
    __ lea(end_to,   end_to_addr);
    __ movptr(r14_length, length);        // save a copy of the length
    assert(length == count, "");          // else fix next line:
    __ negptr(count);                     // negate and test the length
    __ jcc(Assembler::notZero, L_load_element);

    // Empty array:  Nothing to do.
    __ xorptr(rax, rax);                  // return 0 on (trivial) success
    __ jmp(L_done);

    // ======== begin loop ========
    // (Loop is rotated; its entry is L_load_element.)
    // Loop control:
    //   for (count = -count; count != 0; count++)
    // Base pointers src, dst are biased by 8*(count-1),to last element.
    __ align(OptoLoopAlignment);

    __ BIND(L_store_element);
    __ store_heap_oop(to_element_addr, rax_oop);  // store the oop
    __ increment(count);               // increment the count toward zero
    __ jcc(Assembler::zero, L_do_card_marks);

    // ======== loop entry is here ========
    __ BIND(L_load_element);
    __ load_heap_oop(rax_oop, from_element_addr); // load the oop
    __ testptr(rax_oop, rax_oop);
    __ jcc(Assembler::zero, L_store_element);

    __ load_klass(r11_klass, rax_oop);// query the object klass
    generate_type_check(r11_klass, ckoff, ckval, L_store_element);
    // ======== end loop ========

    // It was a real error; we must depend on the caller to finish the job.
    // Register rdx = -1 * number of *remaining* oops, r14 = *total* oops.
    // Emit GC store barriers for the oops we have copied (r14 + rdx),
    // and report their number to the caller.
    assert_different_registers(rax, r14_length, count, to, end_to, rcx);
    __ lea(end_to, to_element_addr);
    __ addptr(end_to, -heapOopSize);      // make an inclusive end pointer
    gen_write_ref_array_post_barrier(to, end_to, rscratch1);
    __ movptr(rax, r14_length);           // original oops
    __ addptr(rax, count);                // K = (original - remaining) oops
    __ notptr(rax);                       // report (-1^K) to caller
    __ jmp(L_done);

    // Come here on success only.
    __ BIND(L_do_card_marks);
    __ addptr(end_to, -heapOopSize);         // make an inclusive end pointer
    gen_write_ref_array_post_barrier(to, end_to, rscratch1);
    __ xorptr(rax, rax);                  // return 0 on success

    // Common exit point (success or failure).
    __ BIND(L_done);
    __ movptr(r13, Address(rsp, saved_r13_offset * wordSize));
    __ movptr(r14, Address(rsp, saved_r14_offset * wordSize));
    inc_counter_np(SharedRuntime::_checkcast_array_copy_ctr);
    restore_arg_regs();
    __ leave(); // required for proper stackwalking of RuntimeStub frame
    __ ret(0);

    return start;
  }

  //
  //  Generate 'unsafe' array copy stub
  //  Though just as safe as the other stubs, it takes an unscaled
  //  size_t argument instead of an element count.
  //
  //  Input:
  //    c_rarg0   - source array address
  //    c_rarg1   - destination array address
  //    c_rarg2   - byte count, treated as ssize_t, can be zero
  //
  // Examines the alignment of the operands and dispatches
  // to a long, int, short, or byte copy loop.
  //
  address generate_unsafe_copy(const char *name) {

    Label L_long_aligned, L_int_aligned, L_short_aligned;

    // Input registers (before setup_arg_regs)
    const Register from        = c_rarg0;  // source array address
    const Register to          = c_rarg1;  // destination array address
    const Register size        = c_rarg2;  // byte count (size_t)

    // Register used as a temp
    const Register bits        = rax;      // test copy of low bits

    __ align(CodeEntryAlignment);
    StubCodeMark mark(this, "StubRoutines", name);
    address start = __ pc();

    __ enter(); // required for proper stackwalking of RuntimeStub frame

    // bump this on entry, not on exit:
    inc_counter_np(SharedRuntime::_unsafe_array_copy_ctr);

    __ mov(bits, from);
    __ orptr(bits, to);
    __ orptr(bits, size);

    __ testb(bits, BytesPerLong-1);
    __ jccb(Assembler::zero, L_long_aligned);

    __ testb(bits, BytesPerInt-1);
    __ jccb(Assembler::zero, L_int_aligned);

    __ testb(bits, BytesPerShort-1);
    __ jump_cc(Assembler::notZero, RuntimeAddress(byte_copy_entry));

    __ BIND(L_short_aligned);
    __ shrptr(size, LogBytesPerShort); // size => short_count
    __ jump(RuntimeAddress(short_copy_entry));

    __ BIND(L_int_aligned);
    __ shrptr(size, LogBytesPerInt); // size => int_count
    __ jump(RuntimeAddress(int_copy_entry));

    __ BIND(L_long_aligned);
    __ shrptr(size, LogBytesPerLong); // size => qword_count
    __ jump(RuntimeAddress(long_copy_entry));

    return start;
  }

  // Perform range checks on the proposed arraycopy.
  // Kills temp, but nothing else.
  // Also, clean the sign bits of src_pos and dst_pos.
  void arraycopy_range_checks(Register src,     // source array oop (c_rarg0)
                              Register src_pos, // source position (c_rarg1)
                              Register dst,     // destination array oo (c_rarg2)
                              Register dst_pos, // destination position (c_rarg3)
                              Register length,
                              Register temp,
                              Label& L_failed) {
    BLOCK_COMMENT("arraycopy_range_checks:");

    //  if (src_pos + length > arrayOop(src)->length())  FAIL;
    __ movl(temp, length);
    __ addl(temp, src_pos);             // src_pos + length
    __ cmpl(temp, Address(src, arrayOopDesc::length_offset_in_bytes()));
    __ jcc(Assembler::above, L_failed);

    //  if (dst_pos + length > arrayOop(dst)->length())  FAIL;
    __ movl(temp, length);
    __ addl(temp, dst_pos);             // dst_pos + length
    __ cmpl(temp, Address(dst, arrayOopDesc::length_offset_in_bytes()));
    __ jcc(Assembler::above, L_failed);

    // Have to clean up high 32-bits of 'src_pos' and 'dst_pos'.
    // Move with sign extension can be used since they are positive.
    __ movslq(src_pos, src_pos);
    __ movslq(dst_pos, dst_pos);

    BLOCK_COMMENT("arraycopy_range_checks done");
  }

  //
  //  Generate generic array copy stubs
  //
  //  Input:
  //    c_rarg0    -  src oop
  //    c_rarg1    -  src_pos (32-bits)
  //    c_rarg2    -  dst oop
  //    c_rarg3    -  dst_pos (32-bits)
  // not Win64
  //    c_rarg4    -  element count (32-bits)
  // Win64
  //    rsp+40     -  element count (32-bits)
  //
  //  Output:
  //    rax ==  0  -  success
  //    rax == -1^K - failure, where K is partial transfer count
  //
  address generate_generic_copy(const char *name) {

    Label L_failed, L_failed_0, L_objArray;
    Label L_copy_bytes, L_copy_shorts, L_copy_ints, L_copy_longs;

    // Input registers
    const Register src        = c_rarg0;  // source array oop
    const Register src_pos    = c_rarg1;  // source position
    const Register dst        = c_rarg2;  // destination array oop
    const Register dst_pos    = c_rarg3;  // destination position
#ifndef _WIN64
    const Register length     = c_rarg4;
#else
    const Address  length(rsp, 6 * wordSize);  // elements count is on stack on Win64
#endif

    { int modulus = CodeEntryAlignment;
      int target  = modulus - 5; // 5 = sizeof jmp(L_failed)
      int advance = target - (__ offset() % modulus);
      if (advance < 0)  advance += modulus;
      if (advance > 0)  __ nop(advance);
    }
    StubCodeMark mark(this, "StubRoutines", name);

    // Short-hop target to L_failed.  Makes for denser prologue code.
    __ BIND(L_failed_0);
    __ jmp(L_failed);
    assert(__ offset() % CodeEntryAlignment == 0, "no further alignment needed");

    __ align(CodeEntryAlignment);
    address start = __ pc();

    __ enter(); // required for proper stackwalking of RuntimeStub frame

    // bump this on entry, not on exit:
    inc_counter_np(SharedRuntime::_generic_array_copy_ctr);

    //-----------------------------------------------------------------------
    // Assembler stub will be used for this call to arraycopy
    // if the following conditions are met:
    //
    // (1) src and dst must not be null.
    // (2) src_pos must not be negative.
    // (3) dst_pos must not be negative.
    // (4) length  must not be negative.
    // (5) src klass and dst klass should be the same and not NULL.
    // (6) src and dst should be arrays.
    // (7) src_pos + length must not exceed length of src.
    // (8) dst_pos + length must not exceed length of dst.
    //

    //  if (src == NULL) return -1;
    __ testptr(src, src);         // src oop
    size_t j1off = __ offset();
    __ jccb(Assembler::zero, L_failed_0);

    //  if (src_pos < 0) return -1;
    __ testl(src_pos, src_pos); // src_pos (32-bits)
    __ jccb(Assembler::negative, L_failed_0);

    //  if (dst == NULL) return -1;
    __ testptr(dst, dst);         // dst oop
    __ jccb(Assembler::zero, L_failed_0);

    //  if (dst_pos < 0) return -1;
    __ testl(dst_pos, dst_pos); // dst_pos (32-bits)
    size_t j4off = __ offset();
    __ jccb(Assembler::negative, L_failed_0);

    // The first four tests are very dense code,
    // but not quite dense enough to put four
    // jumps in a 16-byte instruction fetch buffer.
    // That's good, because some branch predicters
    // do not like jumps so close together.
    // Make sure of this.
    guarantee(((j1off ^ j4off) & ~15) != 0, "I$ line of 1st & 4th jumps");

    // registers used as temp
    const Register r11_length    = r11; // elements count to copy
    const Register r10_src_klass = r10; // array klass

    //  if (length < 0) return -1;
    __ movl(r11_length, length);        // length (elements count, 32-bits value)
    __ testl(r11_length, r11_length);
    __ jccb(Assembler::negative, L_failed_0);

    __ load_klass(r10_src_klass, src);
#ifdef ASSERT
    //  assert(src->klass() != NULL);
    {
      BLOCK_COMMENT("assert klasses not null {");
      Label L1, L2;
      __ testptr(r10_src_klass, r10_src_klass);
      __ jcc(Assembler::notZero, L2);   // it is broken if klass is NULL
      __ bind(L1);
      __ stop("broken null klass");
      __ bind(L2);
      __ load_klass(rax, dst);
      __ cmpq(rax, 0);
      __ jcc(Assembler::equal, L1);     // this would be broken also
      BLOCK_COMMENT("} assert klasses not null done");
    }
#endif

    // Load layout helper (32-bits)
    //
    //  |array_tag|     | header_size | element_type |     |log2_element_size|
    // 32        30    24            16              8     2                 0
    //
    //   array_tag: typeArray = 0x3, objArray = 0x2, non-array = 0x0
    //

    const int lh_offset = klassOopDesc::header_size() * HeapWordSize +
                          Klass::layout_helper_offset_in_bytes();

    // Handle objArrays completely differently...
    const jint objArray_lh = Klass::array_layout_helper(T_OBJECT);
    __ cmpl(Address(r10_src_klass, lh_offset), objArray_lh);
    __ jcc(Assembler::equal, L_objArray);

    //  if (src->klass() != dst->klass()) return -1;
    __ load_klass(rax, dst);
    __ cmpq(r10_src_klass, rax);
    __ jcc(Assembler::notEqual, L_failed);

    const Register rax_lh = rax;  // layout helper
    __ movl(rax_lh, Address(r10_src_klass, lh_offset));

    //  if (!src->is_Array()) return -1;
    __ cmpl(rax_lh, Klass::_lh_neutral_value);
    __ jcc(Assembler::greaterEqual, L_failed);

    // At this point, it is known to be a typeArray (array_tag 0x3).
#ifdef ASSERT
    {
      BLOCK_COMMENT("assert primitive array {");
      Label L;
      __ cmpl(rax_lh, (Klass::_lh_array_tag_type_value << Klass::_lh_array_tag_shift));
      __ jcc(Assembler::greaterEqual, L);
      __ stop("must be a primitive array");
      __ bind(L);
      BLOCK_COMMENT("} assert primitive array done");
    }
#endif

    arraycopy_range_checks(src, src_pos, dst, dst_pos, r11_length,
                           r10, L_failed);

    // typeArrayKlass
    //
    // src_addr = (src + array_header_in_bytes()) + (src_pos << log2elemsize);
    // dst_addr = (dst + array_header_in_bytes()) + (dst_pos << log2elemsize);
    //

    const Register r10_offset = r10;    // array offset
    const Register rax_elsize = rax_lh; // element size

    __ movl(r10_offset, rax_lh);
    __ shrl(r10_offset, Klass::_lh_header_size_shift);
    __ andptr(r10_offset, Klass::_lh_header_size_mask);   // array_offset
    __ addptr(src, r10_offset);           // src array offset
    __ addptr(dst, r10_offset);           // dst array offset
    BLOCK_COMMENT("choose copy loop based on element size");
    __ andl(rax_lh, Klass::_lh_log2_element_size_mask); // rax_lh -> rax_elsize

    // next registers should be set before the jump to corresponding stub
    const Register from     = c_rarg0;  // source array address
    const Register to       = c_rarg1;  // destination array address
    const Register count    = c_rarg2;  // elements count

    // 'from', 'to', 'count' registers should be set in such order
    // since they are the same as 'src', 'src_pos', 'dst'.

  __ BIND(L_copy_bytes);
    __ cmpl(rax_elsize, 0);
    __ jccb(Assembler::notEqual, L_copy_shorts);
    __ lea(from, Address(src, src_pos, Address::times_1, 0));// src_addr
    __ lea(to,   Address(dst, dst_pos, Address::times_1, 0));// dst_addr
    __ movl2ptr(count, r11_length); // length
    __ jump(RuntimeAddress(byte_copy_entry));

  __ BIND(L_copy_shorts);
    __ cmpl(rax_elsize, LogBytesPerShort);
    __ jccb(Assembler::notEqual, L_copy_ints);
    __ lea(from, Address(src, src_pos, Address::times_2, 0));// src_addr
    __ lea(to,   Address(dst, dst_pos, Address::times_2, 0));// dst_addr
    __ movl2ptr(count, r11_length); // length
    __ jump(RuntimeAddress(short_copy_entry));

  __ BIND(L_copy_ints);
    __ cmpl(rax_elsize, LogBytesPerInt);
    __ jccb(Assembler::notEqual, L_copy_longs);
    __ lea(from, Address(src, src_pos, Address::times_4, 0));// src_addr
    __ lea(to,   Address(dst, dst_pos, Address::times_4, 0));// dst_addr
    __ movl2ptr(count, r11_length); // length
    __ jump(RuntimeAddress(int_copy_entry));

  __ BIND(L_copy_longs);
#ifdef ASSERT
    {
      BLOCK_COMMENT("assert long copy {");
      Label L;
      __ cmpl(rax_elsize, LogBytesPerLong);
      __ jcc(Assembler::equal, L);
      __ stop("must be long copy, but elsize is wrong");
      __ bind(L);
      BLOCK_COMMENT("} assert long copy done");
    }
#endif
    __ lea(from, Address(src, src_pos, Address::times_8, 0));// src_addr
    __ lea(to,   Address(dst, dst_pos, Address::times_8, 0));// dst_addr
    __ movl2ptr(count, r11_length); // length
    __ jump(RuntimeAddress(long_copy_entry));

    // objArrayKlass
  __ BIND(L_objArray);
    // live at this point:  r10_src_klass, r11_length, src[_pos], dst[_pos]

    Label L_plain_copy, L_checkcast_copy;
    //  test array classes for subtyping
    __ load_klass(rax, dst);
    __ cmpq(r10_src_klass, rax); // usual case is exact equality
    __ jcc(Assembler::notEqual, L_checkcast_copy);

    // Identically typed arrays can be copied without element-wise checks.
    arraycopy_range_checks(src, src_pos, dst, dst_pos, r11_length,
                           r10, L_failed);

    __ lea(from, Address(src, src_pos, TIMES_OOP,
                 arrayOopDesc::base_offset_in_bytes(T_OBJECT))); // src_addr
    __ lea(to,   Address(dst, dst_pos, TIMES_OOP,
                 arrayOopDesc::base_offset_in_bytes(T_OBJECT))); // dst_addr
    __ movl2ptr(count, r11_length); // length
  __ BIND(L_plain_copy);
    __ jump(RuntimeAddress(oop_copy_entry));

  __ BIND(L_checkcast_copy);
    // live at this point:  r10_src_klass, r11_length, rax (dst_klass)
    {
      // Before looking at dst.length, make sure dst is also an objArray.
      __ cmpl(Address(rax, lh_offset), objArray_lh);
      __ jcc(Assembler::notEqual, L_failed);

      // It is safe to examine both src.length and dst.length.
      arraycopy_range_checks(src, src_pos, dst, dst_pos, r11_length,
                             rax, L_failed);

      const Register r11_dst_klass = r11;
      __ load_klass(r11_dst_klass, dst); // reload

      // Marshal the base address arguments now, freeing registers.
      __ lea(from, Address(src, src_pos, TIMES_OOP,
                   arrayOopDesc::base_offset_in_bytes(T_OBJECT)));
      __ lea(to,   Address(dst, dst_pos, TIMES_OOP,
                   arrayOopDesc::base_offset_in_bytes(T_OBJECT)));
      __ movl(count, length);           // length (reloaded)
      Register sco_temp = c_rarg3;      // this register is free now
      assert_different_registers(from, to, count, sco_temp,
                                 r11_dst_klass, r10_src_klass);
      assert_clean_int(count, sco_temp);

      // Generate the type check.
      const int sco_offset = (klassOopDesc::header_size() * HeapWordSize +
                              Klass::super_check_offset_offset_in_bytes());
      __ movl(sco_temp, Address(r11_dst_klass, sco_offset));
      assert_clean_int(sco_temp, rax);
      generate_type_check(r10_src_klass, sco_temp, r11_dst_klass, L_plain_copy);

      // Fetch destination element klass from the objArrayKlass header.
      int ek_offset = (klassOopDesc::header_size() * HeapWordSize +
                       objArrayKlass::element_klass_offset_in_bytes());
      __ movptr(r11_dst_klass, Address(r11_dst_klass, ek_offset));
      __ movl(  sco_temp,      Address(r11_dst_klass, sco_offset));
      assert_clean_int(sco_temp, rax);

      // the checkcast_copy loop needs two extra arguments:
      assert(c_rarg3 == sco_temp, "#3 already in place");
      // Set up arguments for checkcast_copy_entry.
      setup_arg_regs(4);
      __ movptr(r8, r11_dst_klass);  // dst.klass.element_klass, r8 is c_rarg4 on Linux/Solaris
      __ jump(RuntimeAddress(checkcast_copy_entry));
    }

  __ BIND(L_failed);
    __ xorptr(rax, rax);
    __ notptr(rax); // return -1
    __ leave();   // required for proper stackwalking of RuntimeStub frame
    __ ret(0);

    return start;
  }

  void generate_arraycopy_stubs() {
    // Call the conjoint generation methods immediately after
    // the disjoint ones so that short branches from the former
    // to the latter can be generated.
    StubRoutines::_jbyte_disjoint_arraycopy  = generate_disjoint_byte_copy(false, "jbyte_disjoint_arraycopy");
    StubRoutines::_jbyte_arraycopy           = generate_conjoint_byte_copy(false, "jbyte_arraycopy");

    StubRoutines::_jshort_disjoint_arraycopy = generate_disjoint_short_copy(false, "jshort_disjoint_arraycopy");
    StubRoutines::_jshort_arraycopy          = generate_conjoint_short_copy(false, "jshort_arraycopy");

    StubRoutines::_jint_disjoint_arraycopy   = generate_disjoint_int_oop_copy(false, false, "jint_disjoint_arraycopy");
    StubRoutines::_jint_arraycopy            = generate_conjoint_int_oop_copy(false, false, "jint_arraycopy");

    StubRoutines::_jlong_disjoint_arraycopy  = generate_disjoint_long_oop_copy(false, false, "jlong_disjoint_arraycopy");
    StubRoutines::_jlong_arraycopy           = generate_conjoint_long_oop_copy(false, false, "jlong_arraycopy");


    if (UseCompressedOops) {
      StubRoutines::_oop_disjoint_arraycopy  = generate_disjoint_int_oop_copy(false, true, "oop_disjoint_arraycopy");
      StubRoutines::_oop_arraycopy           = generate_conjoint_int_oop_copy(false, true, "oop_arraycopy");
    } else {
      StubRoutines::_oop_disjoint_arraycopy  = generate_disjoint_long_oop_copy(false, true, "oop_disjoint_arraycopy");
      StubRoutines::_oop_arraycopy           = generate_conjoint_long_oop_copy(false, true, "oop_arraycopy");
    }

    StubRoutines::_checkcast_arraycopy = generate_checkcast_copy("checkcast_arraycopy");
    StubRoutines::_unsafe_arraycopy    = generate_unsafe_copy("unsafe_arraycopy");
    StubRoutines::_generic_arraycopy   = generate_generic_copy("generic_arraycopy");

    StubRoutines::_jbyte_fill = generate_fill(T_BYTE, false, "jbyte_fill");
    StubRoutines::_jshort_fill = generate_fill(T_SHORT, false, "jshort_fill");
    StubRoutines::_jint_fill = generate_fill(T_INT, false, "jint_fill");
    StubRoutines::_arrayof_jbyte_fill = generate_fill(T_BYTE, true, "arrayof_jbyte_fill");
    StubRoutines::_arrayof_jshort_fill = generate_fill(T_SHORT, true, "arrayof_jshort_fill");
    StubRoutines::_arrayof_jint_fill = generate_fill(T_INT, true, "arrayof_jint_fill");

    // We don't generate specialized code for HeapWord-aligned source
    // arrays, so just use the code we've already generated
    StubRoutines::_arrayof_jbyte_disjoint_arraycopy  = StubRoutines::_jbyte_disjoint_arraycopy;
    StubRoutines::_arrayof_jbyte_arraycopy           = StubRoutines::_jbyte_arraycopy;

    StubRoutines::_arrayof_jshort_disjoint_arraycopy = StubRoutines::_jshort_disjoint_arraycopy;
    StubRoutines::_arrayof_jshort_arraycopy          = StubRoutines::_jshort_arraycopy;

    StubRoutines::_arrayof_jint_disjoint_arraycopy   = StubRoutines::_jint_disjoint_arraycopy;
    StubRoutines::_arrayof_jint_arraycopy            = StubRoutines::_jint_arraycopy;

    StubRoutines::_arrayof_jlong_disjoint_arraycopy  = StubRoutines::_jlong_disjoint_arraycopy;
    StubRoutines::_arrayof_jlong_arraycopy           = StubRoutines::_jlong_arraycopy;

    StubRoutines::_arrayof_oop_disjoint_arraycopy    = StubRoutines::_oop_disjoint_arraycopy;
    StubRoutines::_arrayof_oop_arraycopy             = StubRoutines::_oop_arraycopy;
  }

  void generate_math_stubs() {
    {
      StubCodeMark mark(this, "StubRoutines", "log");
      StubRoutines::_intrinsic_log = (double (*)(double)) __ pc();

      __ subq(rsp, 8);
      __ movdbl(Address(rsp, 0), xmm0);
      __ fld_d(Address(rsp, 0));
      __ flog();
      __ fstp_d(Address(rsp, 0));
      __ movdbl(xmm0, Address(rsp, 0));
      __ addq(rsp, 8);
      __ ret(0);
    }
    {
      StubCodeMark mark(this, "StubRoutines", "log10");
      StubRoutines::_intrinsic_log10 = (double (*)(double)) __ pc();

      __ subq(rsp, 8);
      __ movdbl(Address(rsp, 0), xmm0);
      __ fld_d(Address(rsp, 0));
      __ flog10();
      __ fstp_d(Address(rsp, 0));
      __ movdbl(xmm0, Address(rsp, 0));
      __ addq(rsp, 8);
      __ ret(0);
    }
    {
      StubCodeMark mark(this, "StubRoutines", "sin");
      StubRoutines::_intrinsic_sin = (double (*)(double)) __ pc();

      __ subq(rsp, 8);
      __ movdbl(Address(rsp, 0), xmm0);
      __ fld_d(Address(rsp, 0));
      __ trigfunc('s');
      __ fstp_d(Address(rsp, 0));
      __ movdbl(xmm0, Address(rsp, 0));
      __ addq(rsp, 8);
      __ ret(0);
    }
    {
      StubCodeMark mark(this, "StubRoutines", "cos");
      StubRoutines::_intrinsic_cos = (double (*)(double)) __ pc();

      __ subq(rsp, 8);
      __ movdbl(Address(rsp, 0), xmm0);
      __ fld_d(Address(rsp, 0));
      __ trigfunc('c');
      __ fstp_d(Address(rsp, 0));
      __ movdbl(xmm0, Address(rsp, 0));
      __ addq(rsp, 8);
      __ ret(0);
    }
    {
      StubCodeMark mark(this, "StubRoutines", "tan");
      StubRoutines::_intrinsic_tan = (double (*)(double)) __ pc();

      __ subq(rsp, 8);
      __ movdbl(Address(rsp, 0), xmm0);
      __ fld_d(Address(rsp, 0));
      __ trigfunc('t');
      __ fstp_d(Address(rsp, 0));
      __ movdbl(xmm0, Address(rsp, 0));
      __ addq(rsp, 8);
      __ ret(0);
    }

    // The intrinsic version of these seem to return the same value as
    // the strict version.
    StubRoutines::_intrinsic_exp = SharedRuntime::dexp;
    StubRoutines::_intrinsic_pow = SharedRuntime::dpow;
  }

#undef __
#define __ masm->

  // Continuation point for throwing of implicit exceptions that are
  // not handled in the current activation. Fabricates an exception
  // oop and initiates normal exception dispatching in this
  // frame. Since we need to preserve callee-saved values (currently
  // only for C2, but done for C1 as well) we need a callee-saved oop
  // map and therefore have to make these stubs into RuntimeStubs
  // rather than BufferBlobs.  If the compiler needs all registers to
  // be preserved between the fault point and the exception handler
  // then it must assume responsibility for that in
  // AbstractCompiler::continuation_for_implicit_null_exception or
  // continuation_for_implicit_division_by_zero_exception. All other
  // implicit exceptions (e.g., NullPointerException or
  // AbstractMethodError on entry) are either at call sites or
  // otherwise assume that stack unwinding will be initiated, so
  // caller saved registers were assumed volatile in the compiler.
  address generate_throw_exception(const char* name,
                                   address runtime_entry,
                                   bool restore_saved_exception_pc) {
    // Information about frame layout at time of blocking runtime call.
    // Note that we only have to preserve callee-saved registers since
    // the compilers are responsible for supplying a continuation point
    // if they expect all registers to be preserved.
    enum layout {
      rbp_off = frame::arg_reg_save_area_bytes/BytesPerInt,
      rbp_off2,
      return_off,
      return_off2,
      framesize // inclusive of return address
    };

    int insts_size = 512;
    int locs_size  = 64;

    CodeBuffer code(name, insts_size, locs_size);
    OopMapSet* oop_maps  = new OopMapSet();
    MacroAssembler* masm = new MacroAssembler(&code);

    address start = __ pc();

    // This is an inlined and slightly modified version of call_VM
    // which has the ability to fetch the return PC out of
    // thread-local storage and also sets up last_Java_sp slightly
    // differently than the real call_VM
    if (restore_saved_exception_pc) {
      __ movptr(rax,
                Address(r15_thread,
                        in_bytes(JavaThread::saved_exception_pc_offset())));
      __ push(rax);
    }

    __ enter(); // required for proper stackwalking of RuntimeStub frame

    assert(is_even(framesize/2), "sp not 16-byte aligned");

    // return address and rbp are already in place
    __ subptr(rsp, (framesize-4) << LogBytesPerInt); // prolog

    int frame_complete = __ pc() - start;

    // Set up last_Java_sp and last_Java_fp
    __ set_last_Java_frame(rsp, rbp, NULL);

    // Call runtime
    __ movptr(c_rarg0, r15_thread);
    BLOCK_COMMENT("call runtime_entry");
    __ call(RuntimeAddress(runtime_entry));

    // Generate oop map
    OopMap* map = new OopMap(framesize, 0);

    oop_maps->add_gc_map(__ pc() - start, map);

    __ reset_last_Java_frame(true, false);

    __ leave(); // required for proper stackwalking of RuntimeStub frame

    // check for pending exceptions
#ifdef ASSERT
    Label L;
    __ cmpptr(Address(r15_thread, Thread::pending_exception_offset()),
            (int32_t) NULL_WORD);
    __ jcc(Assembler::notEqual, L);
    __ should_not_reach_here();
    __ bind(L);
#endif // ASSERT
    __ jump(RuntimeAddress(StubRoutines::forward_exception_entry()));


    // codeBlob framesize is in words (not VMRegImpl::slot_size)
    RuntimeStub* stub =
      RuntimeStub::new_runtime_stub(name,
                                    &code,
                                    frame_complete,
                                    (framesize >> (LogBytesPerWord - LogBytesPerInt)),
                                    oop_maps, false);
    return stub->entry_point();
  }

  // Initialization
  void generate_initial() {
    // Generates all stubs and initializes the entry points

    // This platform-specific stub is needed by generate_call_stub()
    StubRoutines::x86::_mxcsr_std        = generate_fp_mask("mxcsr_std",        0x0000000000001F80);

    // entry points that exist in all platforms Note: This is code
    // that could be shared among different platforms - however the
    // benefit seems to be smaller than the disadvantage of having a
    // much more complicated generator structure. See also comment in
    // stubRoutines.hpp.

    StubRoutines::_forward_exception_entry = generate_forward_exception();

    StubRoutines::_call_stub_entry =
      generate_call_stub(StubRoutines::_call_stub_return_address);

    // is referenced by megamorphic call
    StubRoutines::_catch_exception_entry = generate_catch_exception();

    // atomic calls
    StubRoutines::_atomic_xchg_entry         = generate_atomic_xchg();
    StubRoutines::_atomic_xchg_ptr_entry     = generate_atomic_xchg_ptr();
    StubRoutines::_atomic_cmpxchg_entry      = generate_atomic_cmpxchg();
    StubRoutines::_atomic_cmpxchg_long_entry = generate_atomic_cmpxchg_long();
    StubRoutines::_atomic_add_entry          = generate_atomic_add();
    StubRoutines::_atomic_add_ptr_entry      = generate_atomic_add_ptr();
    StubRoutines::_fence_entry               = generate_orderaccess_fence();

    StubRoutines::_handler_for_unsafe_access_entry =
      generate_handler_for_unsafe_access();

    // platform dependent
    StubRoutines::x86::_get_previous_fp_entry = generate_get_previous_fp();

    StubRoutines::x86::_verify_mxcsr_entry    = generate_verify_mxcsr();
  }

  void generate_all() {
    // Generates all stubs and initializes the entry points

    // These entry points require SharedInfo::stack0 to be set up in
    // non-core builds and need to be relocatable, so they each
    // fabricate a RuntimeStub internally.
    StubRoutines::_throw_AbstractMethodError_entry =
      generate_throw_exception("AbstractMethodError throw_exception",
                               CAST_FROM_FN_PTR(address,
                                                SharedRuntime::
                                                throw_AbstractMethodError),
                               false);

    StubRoutines::_throw_IncompatibleClassChangeError_entry =
      generate_throw_exception("IncompatibleClassChangeError throw_exception",
                               CAST_FROM_FN_PTR(address,
                                                SharedRuntime::
                                                throw_IncompatibleClassChangeError),
                               false);

    StubRoutines::_throw_ArithmeticException_entry =
      generate_throw_exception("ArithmeticException throw_exception",
                               CAST_FROM_FN_PTR(address,
                                                SharedRuntime::
                                                throw_ArithmeticException),
                               true);

    StubRoutines::_throw_NullPointerException_entry =
      generate_throw_exception("NullPointerException throw_exception",
                               CAST_FROM_FN_PTR(address,
                                                SharedRuntime::
                                                throw_NullPointerException),
                               true);

    StubRoutines::_throw_NullPointerException_at_call_entry =
      generate_throw_exception("NullPointerException at call throw_exception",
                               CAST_FROM_FN_PTR(address,
                                                SharedRuntime::
                                                throw_NullPointerException_at_call),
                               false);

    StubRoutines::_throw_StackOverflowError_entry =
      generate_throw_exception("StackOverflowError throw_exception",
                               CAST_FROM_FN_PTR(address,
                                                SharedRuntime::
                                                throw_StackOverflowError),
                               false);

    // entry points that are platform specific
    StubRoutines::x86::_f2i_fixup = generate_f2i_fixup();
    StubRoutines::x86::_f2l_fixup = generate_f2l_fixup();
    StubRoutines::x86::_d2i_fixup = generate_d2i_fixup();
    StubRoutines::x86::_d2l_fixup = generate_d2l_fixup();

    StubRoutines::x86::_float_sign_mask  = generate_fp_mask("float_sign_mask",  0x7FFFFFFF7FFFFFFF);
    StubRoutines::x86::_float_sign_flip  = generate_fp_mask("float_sign_flip",  0x8000000080000000);
    StubRoutines::x86::_double_sign_mask = generate_fp_mask("double_sign_mask", 0x7FFFFFFFFFFFFFFF);
    StubRoutines::x86::_double_sign_flip = generate_fp_mask("double_sign_flip", 0x8000000000000000);

    // support for verify_oop (must happen after universe_init)
    StubRoutines::_verify_oop_subroutine_entry = generate_verify_oop();

    // arraycopy stubs used by compilers
    generate_arraycopy_stubs();

    generate_math_stubs();
  }

 public:
  StubGenerator(CodeBuffer* code, bool all) : StubCodeGenerator(code) {
    if (all) {
      generate_all();
    } else {
      generate_initial();
    }
  }
}; // end class declaration

address StubGenerator::disjoint_byte_copy_entry  = NULL;
address StubGenerator::disjoint_short_copy_entry = NULL;
address StubGenerator::disjoint_int_copy_entry   = NULL;
address StubGenerator::disjoint_long_copy_entry  = NULL;
address StubGenerator::disjoint_oop_copy_entry   = NULL;

address StubGenerator::byte_copy_entry  = NULL;
address StubGenerator::short_copy_entry = NULL;
address StubGenerator::int_copy_entry   = NULL;
address StubGenerator::long_copy_entry  = NULL;
address StubGenerator::oop_copy_entry   = NULL;

address StubGenerator::checkcast_copy_entry = NULL;

void StubGenerator_generate(CodeBuffer* code, bool all) {
  StubGenerator g(code, all);
}