view src/cpu/x86/vm/methodHandles_x86.cpp @ 2007:5ddfcf4b079e

7003554: (tiered) assert(is_null_object() || handle() != NULL) failed: cannot embed null pointer Summary: C1 with profiling doesn't check whether the MDO has been really allocated, which can silently fail if the perm gen is full. The solution is to check if the allocation failed and bailout out of inlining or compilation. Reviewed-by: kvn, never
author iveresov
date Thu, 02 Dec 2010 17:21:12 -0800
parents f95d63e2154a
children 8d0b933dda2d
line wrap: on
line source

/*
 * Copyright (c) 1997, 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 "interpreter/interpreter.hpp"
#include "memory/allocation.inline.hpp"
#include "prims/methodHandles.hpp"

#define __ _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 ":")

address MethodHandleEntry::start_compiled_entry(MacroAssembler* _masm,
                                                address interpreted_entry) {
  // Just before the actual machine code entry point, allocate space
  // for a MethodHandleEntry::Data record, so that we can manage everything
  // from one base pointer.
  __ align(wordSize);
  address target = __ pc() + sizeof(Data);
  while (__ pc() < target) {
    __ nop();
    __ align(wordSize);
  }

  MethodHandleEntry* me = (MethodHandleEntry*) __ pc();
  me->set_end_address(__ pc());         // set a temporary end_address
  me->set_from_interpreted_entry(interpreted_entry);
  me->set_type_checking_entry(NULL);

  return (address) me;
}

MethodHandleEntry* MethodHandleEntry::finish_compiled_entry(MacroAssembler* _masm,
                                                address start_addr) {
  MethodHandleEntry* me = (MethodHandleEntry*) start_addr;
  assert(me->end_address() == start_addr, "valid ME");

  // Fill in the real end_address:
  __ align(wordSize);
  me->set_end_address(__ pc());

  return me;
}

#ifdef ASSERT
static void verify_argslot(MacroAssembler* _masm, Register argslot_reg,
                           const char* error_message) {
  // Verify that argslot lies within (rsp, rbp].
  Label L_ok, L_bad;
  BLOCK_COMMENT("{ verify_argslot");
  __ cmpptr(argslot_reg, rbp);
  __ jccb(Assembler::above, L_bad);
  __ cmpptr(rsp, argslot_reg);
  __ jccb(Assembler::below, L_ok);
  __ bind(L_bad);
  __ stop(error_message);
  __ bind(L_ok);
  BLOCK_COMMENT("} verify_argslot");
}
#endif


// Code generation
address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm) {
  // rbx: methodOop
  // rcx: receiver method handle (must load from sp[MethodTypeForm.vmslots])
  // rsi/r13: sender SP (must preserve; see prepare_to_jump_from_interpreted)
  // rdx, rdi: garbage temp, blown away

  Register rbx_method = rbx;
  Register rcx_recv   = rcx;
  Register rax_mtype  = rax;
  Register rdx_temp   = rdx;
  Register rdi_temp   = rdi;

  // emit WrongMethodType path first, to enable jccb back-branch from main path
  Label wrong_method_type;
  __ bind(wrong_method_type);
  Label invoke_generic_slow_path;
  assert(methodOopDesc::intrinsic_id_size_in_bytes() == sizeof(u1), "");;
  __ cmpb(Address(rbx_method, methodOopDesc::intrinsic_id_offset_in_bytes()), (int) vmIntrinsics::_invokeExact);
  __ jcc(Assembler::notEqual, invoke_generic_slow_path);
  __ push(rax_mtype);       // required mtype
  __ push(rcx_recv);        // bad mh (1st stacked argument)
  __ jump(ExternalAddress(Interpreter::throw_WrongMethodType_entry()));

  // here's where control starts out:
  __ align(CodeEntryAlignment);
  address entry_point = __ pc();

  // fetch the MethodType from the method handle into rax (the 'check' register)
  {
    Register tem = rbx_method;
    for (jint* pchase = methodOopDesc::method_type_offsets_chain(); (*pchase) != -1; pchase++) {
      __ movptr(rax_mtype, Address(tem, *pchase));
      tem = rax_mtype;          // in case there is another indirection
    }
  }

  // given the MethodType, find out where the MH argument is buried
  __ load_heap_oop(rdx_temp, Address(rax_mtype, __ delayed_value(java_dyn_MethodType::form_offset_in_bytes, rdi_temp)));
  Register rdx_vmslots = rdx_temp;
  __ movl(rdx_vmslots, Address(rdx_temp, __ delayed_value(java_dyn_MethodTypeForm::vmslots_offset_in_bytes, rdi_temp)));
  __ movptr(rcx_recv, __ argument_address(rdx_vmslots));

  trace_method_handle(_masm, "invokeExact");

  __ check_method_handle_type(rax_mtype, rcx_recv, rdi_temp, wrong_method_type);
  __ jump_to_method_handle_entry(rcx_recv, rdi_temp);

  // for invokeGeneric (only), apply argument and result conversions on the fly
  __ bind(invoke_generic_slow_path);
#ifdef ASSERT
  { Label L;
    __ cmpb(Address(rbx_method, methodOopDesc::intrinsic_id_offset_in_bytes()), (int) vmIntrinsics::_invokeGeneric);
    __ jcc(Assembler::equal, L);
    __ stop("bad methodOop::intrinsic_id");
    __ bind(L);
  }
#endif //ASSERT
  Register rbx_temp = rbx_method;  // don't need it now

  // make room on the stack for another pointer:
  Register rcx_argslot = rcx_recv;
  __ lea(rcx_argslot, __ argument_address(rdx_vmslots, 1));
  insert_arg_slots(_masm, 2 * stack_move_unit(), _INSERT_REF_MASK,
                   rcx_argslot, rbx_temp, rdx_temp);

  // load up an adapter from the calling type (Java weaves this)
  __ load_heap_oop(rdx_temp, Address(rax_mtype, __ delayed_value(java_dyn_MethodType::form_offset_in_bytes, rdi_temp)));
  Register rdx_adapter = rdx_temp;
  // __ load_heap_oop(rdx_adapter, Address(rdx_temp, java_dyn_MethodTypeForm::genericInvoker_offset_in_bytes()));
  // deal with old JDK versions:
  __ lea(rdi_temp, Address(rdx_temp, __ delayed_value(java_dyn_MethodTypeForm::genericInvoker_offset_in_bytes, rdi_temp)));
  __ cmpptr(rdi_temp, rdx_temp);
  Label sorry_no_invoke_generic;
  __ jcc(Assembler::below, sorry_no_invoke_generic);

  __ load_heap_oop(rdx_adapter, Address(rdi_temp, 0));
  __ testptr(rdx_adapter, rdx_adapter);
  __ jcc(Assembler::zero, sorry_no_invoke_generic);
  __ movptr(Address(rcx_argslot, 1 * Interpreter::stackElementSize), rdx_adapter);
  // As a trusted first argument, pass the type being called, so the adapter knows
  // the actual types of the arguments and return values.
  // (Generic invokers are shared among form-families of method-type.)
  __ movptr(Address(rcx_argslot, 0 * Interpreter::stackElementSize), rax_mtype);
  // FIXME: assert that rdx_adapter is of the right method-type.
  __ mov(rcx, rdx_adapter);
  trace_method_handle(_masm, "invokeGeneric");
  __ jump_to_method_handle_entry(rcx, rdi_temp);

  __ bind(sorry_no_invoke_generic); // no invokeGeneric implementation available!
  __ movptr(rcx_recv, Address(rcx_argslot, -1 * Interpreter::stackElementSize));  // recover original MH
  __ push(rax_mtype);       // required mtype
  __ push(rcx_recv);        // bad mh (1st stacked argument)
  __ jump(ExternalAddress(Interpreter::throw_WrongMethodType_entry()));

  return entry_point;
}

// Helper to insert argument slots into the stack.
// arg_slots must be a multiple of stack_move_unit() and <= 0
void MethodHandles::insert_arg_slots(MacroAssembler* _masm,
                                     RegisterOrConstant arg_slots,
                                     int arg_mask,
                                     Register rax_argslot,
                                     Register rbx_temp, Register rdx_temp, Register temp3_reg) {
  assert(temp3_reg == noreg, "temp3 not required");
  assert_different_registers(rax_argslot, rbx_temp, rdx_temp,
                             (!arg_slots.is_register() ? rsp : arg_slots.as_register()));

#ifdef ASSERT
  verify_argslot(_masm, rax_argslot, "insertion point must fall within current frame");
  if (arg_slots.is_register()) {
    Label L_ok, L_bad;
    __ cmpptr(arg_slots.as_register(), (int32_t) NULL_WORD);
    __ jccb(Assembler::greater, L_bad);
    __ testl(arg_slots.as_register(), -stack_move_unit() - 1);
    __ jccb(Assembler::zero, L_ok);
    __ bind(L_bad);
    __ stop("assert arg_slots <= 0 and clear low bits");
    __ bind(L_ok);
  } else {
    assert(arg_slots.as_constant() <= 0, "");
    assert(arg_slots.as_constant() % -stack_move_unit() == 0, "");
  }
#endif //ASSERT

#ifdef _LP64
  if (arg_slots.is_register()) {
    // clean high bits of stack motion register (was loaded as an int)
    __ movslq(arg_slots.as_register(), arg_slots.as_register());
  }
#endif

  // Make space on the stack for the inserted argument(s).
  // Then pull down everything shallower than rax_argslot.
  // The stacked return address gets pulled down with everything else.
  // That is, copy [rsp, argslot) downward by -size words.  In pseudo-code:
  //   rsp -= size;
  //   for (rdx = rsp + size; rdx < argslot; rdx++)
  //     rdx[-size] = rdx[0]
  //   argslot -= size;
  BLOCK_COMMENT("insert_arg_slots {");
  __ mov(rdx_temp, rsp);                        // source pointer for copy
  __ lea(rsp, Address(rsp, arg_slots, Address::times_ptr));
  {
    Label loop;
    __ BIND(loop);
    // pull one word down each time through the loop
    __ movptr(rbx_temp, Address(rdx_temp, 0));
    __ movptr(Address(rdx_temp, arg_slots, Address::times_ptr), rbx_temp);
    __ addptr(rdx_temp, wordSize);
    __ cmpptr(rdx_temp, rax_argslot);
    __ jccb(Assembler::less, loop);
  }

  // Now move the argslot down, to point to the opened-up space.
  __ lea(rax_argslot, Address(rax_argslot, arg_slots, Address::times_ptr));
  BLOCK_COMMENT("} insert_arg_slots");
}

// Helper to remove argument slots from the stack.
// arg_slots must be a multiple of stack_move_unit() and >= 0
void MethodHandles::remove_arg_slots(MacroAssembler* _masm,
                                    RegisterOrConstant arg_slots,
                                    Register rax_argslot,
                                     Register rbx_temp, Register rdx_temp, Register temp3_reg) {
  assert(temp3_reg == noreg, "temp3 not required");
  assert_different_registers(rax_argslot, rbx_temp, rdx_temp,
                             (!arg_slots.is_register() ? rsp : arg_slots.as_register()));

#ifdef ASSERT
  // Verify that [argslot..argslot+size) lies within (rsp, rbp).
  __ lea(rbx_temp, Address(rax_argslot, arg_slots, Address::times_ptr));
  verify_argslot(_masm, rbx_temp, "deleted argument(s) must fall within current frame");
  if (arg_slots.is_register()) {
    Label L_ok, L_bad;
    __ cmpptr(arg_slots.as_register(), (int32_t) NULL_WORD);
    __ jccb(Assembler::less, L_bad);
    __ testl(arg_slots.as_register(), -stack_move_unit() - 1);
    __ jccb(Assembler::zero, L_ok);
    __ bind(L_bad);
    __ stop("assert arg_slots >= 0 and clear low bits");
    __ bind(L_ok);
  } else {
    assert(arg_slots.as_constant() >= 0, "");
    assert(arg_slots.as_constant() % -stack_move_unit() == 0, "");
  }
#endif //ASSERT

#ifdef _LP64
  if (false) {                  // not needed, since register is positive
    // clean high bits of stack motion register (was loaded as an int)
    if (arg_slots.is_register())
      __ movslq(arg_slots.as_register(), arg_slots.as_register());
  }
#endif

  BLOCK_COMMENT("remove_arg_slots {");
  // Pull up everything shallower than rax_argslot.
  // Then remove the excess space on the stack.
  // The stacked return address gets pulled up with everything else.
  // That is, copy [rsp, argslot) upward by size words.  In pseudo-code:
  //   for (rdx = argslot-1; rdx >= rsp; --rdx)
  //     rdx[size] = rdx[0]
  //   argslot += size;
  //   rsp += size;
  __ lea(rdx_temp, Address(rax_argslot, -wordSize)); // source pointer for copy
  {
    Label loop;
    __ BIND(loop);
    // pull one word up each time through the loop
    __ movptr(rbx_temp, Address(rdx_temp, 0));
    __ movptr(Address(rdx_temp, arg_slots, Address::times_ptr), rbx_temp);
    __ addptr(rdx_temp, -wordSize);
    __ cmpptr(rdx_temp, rsp);
    __ jccb(Assembler::greaterEqual, loop);
  }

  // Now move the argslot up, to point to the just-copied block.
  __ lea(rsp, Address(rsp, arg_slots, Address::times_ptr));
  // And adjust the argslot address to point at the deletion point.
  __ lea(rax_argslot, Address(rax_argslot, arg_slots, Address::times_ptr));
  BLOCK_COMMENT("} remove_arg_slots");
}

#ifndef PRODUCT
extern "C" void print_method_handle(oop mh);
void trace_method_handle_stub(const char* adaptername,
                              oop mh,
                              intptr_t* saved_regs,
                              intptr_t* entry_sp,
                              intptr_t* saved_sp,
                              intptr_t* saved_bp) {
  // called as a leaf from native code: do not block the JVM!
  intptr_t* last_sp = (intptr_t*) saved_bp[frame::interpreter_frame_last_sp_offset];
  intptr_t* base_sp = (intptr_t*) saved_bp[frame::interpreter_frame_monitor_block_top_offset];
  printf("MH %s mh="INTPTR_FORMAT" sp=("INTPTR_FORMAT"+"INTX_FORMAT") stack_size="INTX_FORMAT" bp="INTPTR_FORMAT"\n",
         adaptername, (intptr_t)mh, (intptr_t)entry_sp, (intptr_t)(saved_sp - entry_sp), (intptr_t)(base_sp - last_sp), (intptr_t)saved_bp);
  if (last_sp != saved_sp && last_sp != NULL)
    printf("*** last_sp="INTPTR_FORMAT"\n", (intptr_t)last_sp);
  if (Verbose) {
    printf(" reg dump: ");
    int saved_regs_count = (entry_sp-1) - saved_regs;
    // 32 bit: rdi rsi rbp rsp; rbx rdx rcx (*) rax
    int i;
    for (i = 0; i <= saved_regs_count; i++) {
      if (i > 0 && i % 4 == 0 && i != saved_regs_count)
        printf("\n   + dump: ");
      printf(" %d: "INTPTR_FORMAT, i, saved_regs[i]);
    }
    printf("\n");
    int stack_dump_count = 16;
    if (stack_dump_count < (int)(saved_bp + 2 - saved_sp))
      stack_dump_count = (int)(saved_bp + 2 - saved_sp);
    if (stack_dump_count > 64)  stack_dump_count = 48;
    for (i = 0; i < stack_dump_count; i += 4) {
      printf(" dump at SP[%d] "INTPTR_FORMAT": "INTPTR_FORMAT" "INTPTR_FORMAT" "INTPTR_FORMAT" "INTPTR_FORMAT"\n",
             i, (intptr_t) &entry_sp[i+0], entry_sp[i+0], entry_sp[i+1], entry_sp[i+2], entry_sp[i+3]);
    }
    print_method_handle(mh);
  }
}
void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) {
  if (!TraceMethodHandles)  return;
  BLOCK_COMMENT("trace_method_handle {");
  __ push(rax);
  __ lea(rax, Address(rsp, wordSize*6)); // entry_sp
  __ pusha();
  // arguments:
  __ push(rbp);               // interpreter frame pointer
  __ push(rsi);               // saved_sp
  __ push(rax);               // entry_sp
  __ push(rcx);               // mh
  __ push(rcx);
  __ movptr(Address(rsp, 0), (intptr_t) adaptername);
  __ call_VM_leaf(CAST_FROM_FN_PTR(address, trace_method_handle_stub), 5);
  __ popa();
  __ pop(rax);
  BLOCK_COMMENT("} trace_method_handle");
}
#endif //PRODUCT

// which conversion op types are implemented here?
int MethodHandles::adapter_conversion_ops_supported_mask() {
  return ((1<<sun_dyn_AdapterMethodHandle::OP_RETYPE_ONLY)
         |(1<<sun_dyn_AdapterMethodHandle::OP_RETYPE_RAW)
         |(1<<sun_dyn_AdapterMethodHandle::OP_CHECK_CAST)
         |(1<<sun_dyn_AdapterMethodHandle::OP_PRIM_TO_PRIM)
         |(1<<sun_dyn_AdapterMethodHandle::OP_REF_TO_PRIM)
         |(1<<sun_dyn_AdapterMethodHandle::OP_SWAP_ARGS)
         |(1<<sun_dyn_AdapterMethodHandle::OP_ROT_ARGS)
         |(1<<sun_dyn_AdapterMethodHandle::OP_DUP_ARGS)
         |(1<<sun_dyn_AdapterMethodHandle::OP_DROP_ARGS)
         //|(1<<sun_dyn_AdapterMethodHandle::OP_SPREAD_ARGS) //BUG!
         );
  // FIXME: MethodHandlesTest gets a crash if we enable OP_SPREAD_ARGS.
}

// Generate an "entry" field for a method handle.
// This determines how the method handle will respond to calls.
void MethodHandles::generate_method_handle_stub(MacroAssembler* _masm, MethodHandles::EntryKind ek) {
  // Here is the register state during an interpreted call,
  // as set up by generate_method_handle_interpreter_entry():
  // - rbx: garbage temp (was MethodHandle.invoke methodOop, unused)
  // - rcx: receiver method handle
  // - rax: method handle type (only used by the check_mtype entry point)
  // - rsi/r13: sender SP (must preserve; see prepare_to_jump_from_interpreted)
  // - rdx: garbage temp, can blow away

  Register rcx_recv    = rcx;
  Register rax_argslot = rax;
  Register rbx_temp    = rbx;
  Register rdx_temp    = rdx;

  // This guy is set up by prepare_to_jump_from_interpreted (from interpreted calls)
  // and gen_c2i_adapter (from compiled calls):
  Register saved_last_sp = LP64_ONLY(r13) NOT_LP64(rsi);

  guarantee(java_dyn_MethodHandle::vmentry_offset_in_bytes() != 0, "must have offsets");

  // some handy addresses
  Address rbx_method_fie(     rbx,      methodOopDesc::from_interpreted_offset() );

  Address rcx_mh_vmtarget(    rcx_recv, java_dyn_MethodHandle::vmtarget_offset_in_bytes() );
  Address rcx_dmh_vmindex(    rcx_recv, sun_dyn_DirectMethodHandle::vmindex_offset_in_bytes() );

  Address rcx_bmh_vmargslot(  rcx_recv, sun_dyn_BoundMethodHandle::vmargslot_offset_in_bytes() );
  Address rcx_bmh_argument(   rcx_recv, sun_dyn_BoundMethodHandle::argument_offset_in_bytes() );

  Address rcx_amh_vmargslot(  rcx_recv, sun_dyn_AdapterMethodHandle::vmargslot_offset_in_bytes() );
  Address rcx_amh_argument(   rcx_recv, sun_dyn_AdapterMethodHandle::argument_offset_in_bytes() );
  Address rcx_amh_conversion( rcx_recv, sun_dyn_AdapterMethodHandle::conversion_offset_in_bytes() );
  Address vmarg;                // __ argument_address(vmargslot)

  const int java_mirror_offset = klassOopDesc::klass_part_offset_in_bytes() + Klass::java_mirror_offset_in_bytes();

  if (have_entry(ek)) {
    __ nop();                   // empty stubs make SG sick
    return;
  }

  address interp_entry = __ pc();

  trace_method_handle(_masm, entry_name(ek));

  BLOCK_COMMENT(entry_name(ek));

  switch ((int) ek) {
  case _raise_exception:
    {
      // Not a real MH entry, but rather shared code for raising an exception.
      // Extra local arguments are pushed on stack, as required type at TOS+8,
      // failing object (or NULL) at TOS+4, failing bytecode type at TOS.
      // Beyond those local arguments are the PC, of course.
      Register rdx_code = rdx_temp;
      Register rcx_fail = rcx_recv;
      Register rax_want = rax_argslot;
      Register rdi_pc   = rdi;
      __ pop(rdx_code);  // TOS+0
      __ pop(rcx_fail);  // TOS+4
      __ pop(rax_want);  // TOS+8
      __ pop(rdi_pc);    // caller PC

      __ mov(rsp, rsi);   // cut the stack back to where the caller started

      // Repush the arguments as if coming from the interpreter.
      __ push(rdx_code);
      __ push(rcx_fail);
      __ push(rax_want);

      Register rbx_method = rbx_temp;
      Label no_method;
      // FIXME: fill in _raise_exception_method with a suitable sun.dyn method
      __ movptr(rbx_method, ExternalAddress((address) &_raise_exception_method));
      __ testptr(rbx_method, rbx_method);
      __ jccb(Assembler::zero, no_method);
      int jobject_oop_offset = 0;
      __ movptr(rbx_method, Address(rbx_method, jobject_oop_offset));  // dereference the jobject
      __ testptr(rbx_method, rbx_method);
      __ jccb(Assembler::zero, no_method);
      __ verify_oop(rbx_method);
      __ push(rdi_pc);          // and restore caller PC
      __ jmp(rbx_method_fie);

      // If we get here, the Java runtime did not do its job of creating the exception.
      // Do something that is at least causes a valid throw from the interpreter.
      __ bind(no_method);
      __ pop(rax_want);
      __ pop(rcx_fail);
      __ push(rax_want);
      __ push(rcx_fail);
      __ jump(ExternalAddress(Interpreter::throw_WrongMethodType_entry()));
    }
    break;

  case _invokestatic_mh:
  case _invokespecial_mh:
    {
      Register rbx_method = rbx_temp;
      __ load_heap_oop(rbx_method, rcx_mh_vmtarget); // target is a methodOop
      __ verify_oop(rbx_method);
      // same as TemplateTable::invokestatic or invokespecial,
      // minus the CP setup and profiling:
      if (ek == _invokespecial_mh) {
        // Must load & check the first argument before entering the target method.
        __ load_method_handle_vmslots(rax_argslot, rcx_recv, rdx_temp);
        __ movptr(rcx_recv, __ argument_address(rax_argslot, -1));
        __ null_check(rcx_recv);
        __ verify_oop(rcx_recv);
      }
      __ jmp(rbx_method_fie);
    }
    break;

  case _invokevirtual_mh:
    {
      // same as TemplateTable::invokevirtual,
      // minus the CP setup and profiling:

      // pick out the vtable index and receiver offset from the MH,
      // and then we can discard it:
      __ load_method_handle_vmslots(rax_argslot, rcx_recv, rdx_temp);
      Register rbx_index = rbx_temp;
      __ movl(rbx_index, rcx_dmh_vmindex);
      // Note:  The verifier allows us to ignore rcx_mh_vmtarget.
      __ movptr(rcx_recv, __ argument_address(rax_argslot, -1));
      __ null_check(rcx_recv, oopDesc::klass_offset_in_bytes());

      // get receiver klass
      Register rax_klass = rax_argslot;
      __ load_klass(rax_klass, rcx_recv);
      __ verify_oop(rax_klass);

      // get target methodOop & entry point
      const int base = instanceKlass::vtable_start_offset() * wordSize;
      assert(vtableEntry::size() * wordSize == wordSize, "adjust the scaling in the code below");
      Address vtable_entry_addr(rax_klass,
                                rbx_index, Address::times_ptr,
                                base + vtableEntry::method_offset_in_bytes());
      Register rbx_method = rbx_temp;
      __ movptr(rbx_method, vtable_entry_addr);

      __ verify_oop(rbx_method);
      __ jmp(rbx_method_fie);
    }
    break;

  case _invokeinterface_mh:
    {
      // same as TemplateTable::invokeinterface,
      // minus the CP setup and profiling:

      // pick out the interface and itable index from the MH.
      __ load_method_handle_vmslots(rax_argslot, rcx_recv, rdx_temp);
      Register rdx_intf  = rdx_temp;
      Register rbx_index = rbx_temp;
      __ load_heap_oop(rdx_intf, rcx_mh_vmtarget);
      __ movl(rbx_index, rcx_dmh_vmindex);
      __ movptr(rcx_recv, __ argument_address(rax_argslot, -1));
      __ null_check(rcx_recv, oopDesc::klass_offset_in_bytes());

      // get receiver klass
      Register rax_klass = rax_argslot;
      __ load_klass(rax_klass, rcx_recv);
      __ verify_oop(rax_klass);

      Register rdi_temp   = rdi;
      Register rbx_method = rbx_index;

      // get interface klass
      Label no_such_interface;
      __ verify_oop(rdx_intf);
      __ lookup_interface_method(rax_klass, rdx_intf,
                                 // note: next two args must be the same:
                                 rbx_index, rbx_method,
                                 rdi_temp,
                                 no_such_interface);

      __ verify_oop(rbx_method);
      __ jmp(rbx_method_fie);
      __ hlt();

      __ bind(no_such_interface);
      // Throw an exception.
      // For historical reasons, it will be IncompatibleClassChangeError.
      __ pushptr(Address(rdx_intf, java_mirror_offset));  // required interface
      __ push(rcx_recv);        // bad receiver
      __ push((int)Bytecodes::_invokeinterface);  // who is complaining?
      __ jump(ExternalAddress(from_interpreted_entry(_raise_exception)));
    }
    break;

  case _bound_ref_mh:
  case _bound_int_mh:
  case _bound_long_mh:
  case _bound_ref_direct_mh:
  case _bound_int_direct_mh:
  case _bound_long_direct_mh:
    {
      bool direct_to_method = (ek >= _bound_ref_direct_mh);
      BasicType arg_type  = T_ILLEGAL;
      int       arg_mask  = _INSERT_NO_MASK;
      int       arg_slots = -1;
      get_ek_bound_mh_info(ek, arg_type, arg_mask, arg_slots);

      // make room for the new argument:
      __ movl(rax_argslot, rcx_bmh_vmargslot);
      __ lea(rax_argslot, __ argument_address(rax_argslot));
      insert_arg_slots(_masm, arg_slots * stack_move_unit(), arg_mask,
                       rax_argslot, rbx_temp, rdx_temp);

      // store bound argument into the new stack slot:
      __ load_heap_oop(rbx_temp, rcx_bmh_argument);
      Address prim_value_addr(rbx_temp, java_lang_boxing_object::value_offset_in_bytes(arg_type));
      if (arg_type == T_OBJECT) {
        __ movptr(Address(rax_argslot, 0), rbx_temp);
      } else {
        __ load_sized_value(rdx_temp, prim_value_addr,
                            type2aelembytes(arg_type), is_signed_subword_type(arg_type));
        __ movptr(Address(rax_argslot, 0), rdx_temp);
#ifndef _LP64
        if (arg_slots == 2) {
          __ movl(rdx_temp, prim_value_addr.plus_disp(wordSize));
          __ movl(Address(rax_argslot, Interpreter::stackElementSize), rdx_temp);
        }
#endif //_LP64
      }

      if (direct_to_method) {
        Register rbx_method = rbx_temp;
        __ load_heap_oop(rbx_method, rcx_mh_vmtarget);
        __ verify_oop(rbx_method);
        __ jmp(rbx_method_fie);
      } else {
        __ load_heap_oop(rcx_recv, rcx_mh_vmtarget);
        __ verify_oop(rcx_recv);
        __ jump_to_method_handle_entry(rcx_recv, rdx_temp);
      }
    }
    break;

  case _adapter_retype_only:
  case _adapter_retype_raw:
    // immediately jump to the next MH layer:
    __ load_heap_oop(rcx_recv, rcx_mh_vmtarget);
    __ verify_oop(rcx_recv);
    __ jump_to_method_handle_entry(rcx_recv, rdx_temp);
    // This is OK when all parameter types widen.
    // It is also OK when a return type narrows.
    break;

  case _adapter_check_cast:
    {
      // temps:
      Register rbx_klass = rbx_temp; // interesting AMH data

      // check a reference argument before jumping to the next layer of MH:
      __ movl(rax_argslot, rcx_amh_vmargslot);
      vmarg = __ argument_address(rax_argslot);

      // What class are we casting to?
      __ load_heap_oop(rbx_klass, rcx_amh_argument); // this is a Class object!
      __ load_heap_oop(rbx_klass, Address(rbx_klass, java_lang_Class::klass_offset_in_bytes()));

      Label done;
      __ movptr(rdx_temp, vmarg);
      __ testptr(rdx_temp, rdx_temp);
      __ jcc(Assembler::zero, done);         // no cast if null
      __ load_klass(rdx_temp, rdx_temp);

      // live at this point:
      // - rbx_klass:  klass required by the target method
      // - rdx_temp:   argument klass to test
      // - rcx_recv:   adapter method handle
      __ check_klass_subtype(rdx_temp, rbx_klass, rax_argslot, done);

      // If we get here, the type check failed!
      // Call the wrong_method_type stub, passing the failing argument type in rax.
      Register rax_mtype = rax_argslot;
      __ movl(rax_argslot, rcx_amh_vmargslot);  // reload argslot field
      __ movptr(rdx_temp, vmarg);

      __ load_heap_oop(rbx_klass, rcx_amh_argument); // required class
      __ push(rbx_klass);
      __ push(rdx_temp);                             // bad object
      __ push((int)Bytecodes::_checkcast);           // who is complaining?
      __ jump(ExternalAddress(from_interpreted_entry(_raise_exception)));

      __ bind(done);
      // get the new MH:
      __ load_heap_oop(rcx_recv, rcx_mh_vmtarget);
      __ jump_to_method_handle_entry(rcx_recv, rdx_temp);
    }
    break;

  case _adapter_prim_to_prim:
  case _adapter_ref_to_prim:
    // handled completely by optimized cases
    __ stop("init_AdapterMethodHandle should not issue this");
    break;

  case _adapter_opt_i2i:        // optimized subcase of adapt_prim_to_prim
//case _adapter_opt_f2i:        // optimized subcase of adapt_prim_to_prim
  case _adapter_opt_l2i:        // optimized subcase of adapt_prim_to_prim
  case _adapter_opt_unboxi:     // optimized subcase of adapt_ref_to_prim
    {
      // perform an in-place conversion to int or an int subword
      __ movl(rax_argslot, rcx_amh_vmargslot);
      vmarg = __ argument_address(rax_argslot);

      switch (ek) {
      case _adapter_opt_i2i:
        __ movl(rdx_temp, vmarg);
        break;
      case _adapter_opt_l2i:
        {
          // just delete the extra slot; on a little-endian machine we keep the first
          __ lea(rax_argslot, __ argument_address(rax_argslot, 1));
          remove_arg_slots(_masm, -stack_move_unit(),
                           rax_argslot, rbx_temp, rdx_temp);
          vmarg = Address(rax_argslot, -Interpreter::stackElementSize);
          __ movl(rdx_temp, vmarg);
        }
        break;
      case _adapter_opt_unboxi:
        {
          // Load the value up from the heap.
          __ movptr(rdx_temp, vmarg);
          int value_offset = java_lang_boxing_object::value_offset_in_bytes(T_INT);
#ifdef ASSERT
          for (int bt = T_BOOLEAN; bt < T_INT; bt++) {
            if (is_subword_type(BasicType(bt)))
              assert(value_offset == java_lang_boxing_object::value_offset_in_bytes(BasicType(bt)), "");
          }
#endif
          __ null_check(rdx_temp, value_offset);
          __ movl(rdx_temp, Address(rdx_temp, value_offset));
          // We load this as a word.  Because we are little-endian,
          // the low bits will be correct, but the high bits may need cleaning.
          // The vminfo will guide us to clean those bits.
        }
        break;
      default:
        ShouldNotReachHere();
      }

      // Do the requested conversion and store the value.
      Register rbx_vminfo = rbx_temp;
      __ movl(rbx_vminfo, rcx_amh_conversion);
      assert(CONV_VMINFO_SHIFT == 0, "preshifted");

      // get the new MH:
      __ load_heap_oop(rcx_recv, rcx_mh_vmtarget);
      // (now we are done with the old MH)

      // original 32-bit vmdata word must be of this form:
      //    | MBZ:6 | signBitCount:8 | srcDstTypes:8 | conversionOp:8 |
      __ xchgptr(rcx, rbx_vminfo);                // free rcx for shifts
      __ shll(rdx_temp /*, rcx*/);
      Label zero_extend, done;
      __ testl(rcx, CONV_VMINFO_SIGN_FLAG);
      __ jccb(Assembler::zero, zero_extend);

      // this path is taken for int->byte, int->short
      __ sarl(rdx_temp /*, rcx*/);
      __ jmpb(done);

      __ bind(zero_extend);
      // this is taken for int->char
      __ shrl(rdx_temp /*, rcx*/);

      __ bind(done);
      __ movl(vmarg, rdx_temp);  // Store the value.
      __ xchgptr(rcx, rbx_vminfo);                // restore rcx_recv

      __ jump_to_method_handle_entry(rcx_recv, rdx_temp);
    }
    break;

  case _adapter_opt_i2l:        // optimized subcase of adapt_prim_to_prim
  case _adapter_opt_unboxl:     // optimized subcase of adapt_ref_to_prim
    {
      // perform an in-place int-to-long or ref-to-long conversion
      __ movl(rax_argslot, rcx_amh_vmargslot);

      // on a little-endian machine we keep the first slot and add another after
      __ lea(rax_argslot, __ argument_address(rax_argslot, 1));
      insert_arg_slots(_masm, stack_move_unit(), _INSERT_INT_MASK,
                       rax_argslot, rbx_temp, rdx_temp);
      Address vmarg1(rax_argslot, -Interpreter::stackElementSize);
      Address vmarg2 = vmarg1.plus_disp(Interpreter::stackElementSize);

      switch (ek) {
      case _adapter_opt_i2l:
        {
#ifdef _LP64
          __ movslq(rdx_temp, vmarg1);  // Load sign-extended
          __ movq(vmarg1, rdx_temp);    // Store into first slot
#else
          __ movl(rdx_temp, vmarg1);
          __ sarl(rdx_temp, BitsPerInt - 1);  // __ extend_sign()
          __ movl(vmarg2, rdx_temp); // store second word
#endif
        }
        break;
      case _adapter_opt_unboxl:
        {
          // Load the value up from the heap.
          __ movptr(rdx_temp, vmarg1);
          int value_offset = java_lang_boxing_object::value_offset_in_bytes(T_LONG);
          assert(value_offset == java_lang_boxing_object::value_offset_in_bytes(T_DOUBLE), "");
          __ null_check(rdx_temp, value_offset);
#ifdef _LP64
          __ movq(rbx_temp, Address(rdx_temp, value_offset));
          __ movq(vmarg1, rbx_temp);
#else
          __ movl(rbx_temp, Address(rdx_temp, value_offset + 0*BytesPerInt));
          __ movl(rdx_temp, Address(rdx_temp, value_offset + 1*BytesPerInt));
          __ movl(vmarg1, rbx_temp);
          __ movl(vmarg2, rdx_temp);
#endif
        }
        break;
      default:
        ShouldNotReachHere();
      }

      __ load_heap_oop(rcx_recv, rcx_mh_vmtarget);
      __ jump_to_method_handle_entry(rcx_recv, rdx_temp);
    }
    break;

  case _adapter_opt_f2d:        // optimized subcase of adapt_prim_to_prim
  case _adapter_opt_d2f:        // optimized subcase of adapt_prim_to_prim
    {
      // perform an in-place floating primitive conversion
      __ movl(rax_argslot, rcx_amh_vmargslot);
      __ lea(rax_argslot, __ argument_address(rax_argslot, 1));
      if (ek == _adapter_opt_f2d) {
        insert_arg_slots(_masm, stack_move_unit(), _INSERT_INT_MASK,
                         rax_argslot, rbx_temp, rdx_temp);
      }
      Address vmarg(rax_argslot, -Interpreter::stackElementSize);

#ifdef _LP64
      if (ek == _adapter_opt_f2d) {
        __ movflt(xmm0, vmarg);
        __ cvtss2sd(xmm0, xmm0);
        __ movdbl(vmarg, xmm0);
      } else {
        __ movdbl(xmm0, vmarg);
        __ cvtsd2ss(xmm0, xmm0);
        __ movflt(vmarg, xmm0);
      }
#else //_LP64
      if (ek == _adapter_opt_f2d) {
        __ fld_s(vmarg);        // load float to ST0
        __ fstp_s(vmarg);       // store single
      } else {
        __ fld_d(vmarg);        // load double to ST0
        __ fstp_s(vmarg);       // store single
      }
#endif //_LP64

      if (ek == _adapter_opt_d2f) {
        remove_arg_slots(_masm, -stack_move_unit(),
                         rax_argslot, rbx_temp, rdx_temp);
      }

      __ load_heap_oop(rcx_recv, rcx_mh_vmtarget);
      __ jump_to_method_handle_entry(rcx_recv, rdx_temp);
    }
    break;

  case _adapter_prim_to_ref:
    __ unimplemented(entry_name(ek)); // %%% FIXME: NYI
    break;

  case _adapter_swap_args:
  case _adapter_rot_args:
    // handled completely by optimized cases
    __ stop("init_AdapterMethodHandle should not issue this");
    break;

  case _adapter_opt_swap_1:
  case _adapter_opt_swap_2:
  case _adapter_opt_rot_1_up:
  case _adapter_opt_rot_1_down:
  case _adapter_opt_rot_2_up:
  case _adapter_opt_rot_2_down:
    {
      int swap_bytes = 0, rotate = 0;
      get_ek_adapter_opt_swap_rot_info(ek, swap_bytes, rotate);

      // 'argslot' is the position of the first argument to swap
      __ movl(rax_argslot, rcx_amh_vmargslot);
      __ lea(rax_argslot, __ argument_address(rax_argslot));

      // 'vminfo' is the second
      Register rbx_destslot = rbx_temp;
      __ movl(rbx_destslot, rcx_amh_conversion);
      assert(CONV_VMINFO_SHIFT == 0, "preshifted");
      __ andl(rbx_destslot, CONV_VMINFO_MASK);
      __ lea(rbx_destslot, __ argument_address(rbx_destslot));
      DEBUG_ONLY(verify_argslot(_masm, rbx_destslot, "swap point must fall within current frame"));

      if (!rotate) {
        for (int i = 0; i < swap_bytes; i += wordSize) {
          __ movptr(rdx_temp, Address(rax_argslot , i));
          __ push(rdx_temp);
          __ movptr(rdx_temp, Address(rbx_destslot, i));
          __ movptr(Address(rax_argslot, i), rdx_temp);
          __ pop(rdx_temp);
          __ movptr(Address(rbx_destslot, i), rdx_temp);
        }
      } else {
        // push the first chunk, which is going to get overwritten
        for (int i = swap_bytes; (i -= wordSize) >= 0; ) {
          __ movptr(rdx_temp, Address(rax_argslot, i));
          __ push(rdx_temp);
        }

        if (rotate > 0) {
          // rotate upward
          __ subptr(rax_argslot, swap_bytes);
#ifdef ASSERT
          {
            // Verify that argslot > destslot, by at least swap_bytes.
            Label L_ok;
            __ cmpptr(rax_argslot, rbx_destslot);
            __ jccb(Assembler::aboveEqual, L_ok);
            __ stop("source must be above destination (upward rotation)");
            __ bind(L_ok);
          }
#endif
          // work argslot down to destslot, copying contiguous data upwards
          // pseudo-code:
          //   rax = src_addr - swap_bytes
          //   rbx = dest_addr
          //   while (rax >= rbx) *(rax + swap_bytes) = *(rax + 0), rax--;
          Label loop;
          __ bind(loop);
          __ movptr(rdx_temp, Address(rax_argslot, 0));
          __ movptr(Address(rax_argslot, swap_bytes), rdx_temp);
          __ addptr(rax_argslot, -wordSize);
          __ cmpptr(rax_argslot, rbx_destslot);
          __ jccb(Assembler::aboveEqual, loop);
        } else {
          __ addptr(rax_argslot, swap_bytes);
#ifdef ASSERT
          {
            // Verify that argslot < destslot, by at least swap_bytes.
            Label L_ok;
            __ cmpptr(rax_argslot, rbx_destslot);
            __ jccb(Assembler::belowEqual, L_ok);
            __ stop("source must be below destination (downward rotation)");
            __ bind(L_ok);
          }
#endif
          // work argslot up to destslot, copying contiguous data downwards
          // pseudo-code:
          //   rax = src_addr + swap_bytes
          //   rbx = dest_addr
          //   while (rax <= rbx) *(rax - swap_bytes) = *(rax + 0), rax++;
          Label loop;
          __ bind(loop);
          __ movptr(rdx_temp, Address(rax_argslot, 0));
          __ movptr(Address(rax_argslot, -swap_bytes), rdx_temp);
          __ addptr(rax_argslot, wordSize);
          __ cmpptr(rax_argslot, rbx_destslot);
          __ jccb(Assembler::belowEqual, loop);
        }

        // pop the original first chunk into the destination slot, now free
        for (int i = 0; i < swap_bytes; i += wordSize) {
          __ pop(rdx_temp);
          __ movptr(Address(rbx_destslot, i), rdx_temp);
        }
      }

      __ load_heap_oop(rcx_recv, rcx_mh_vmtarget);
      __ jump_to_method_handle_entry(rcx_recv, rdx_temp);
    }
    break;

  case _adapter_dup_args:
    {
      // 'argslot' is the position of the first argument to duplicate
      __ movl(rax_argslot, rcx_amh_vmargslot);
      __ lea(rax_argslot, __ argument_address(rax_argslot));

      // 'stack_move' is negative number of words to duplicate
      Register rdx_stack_move = rdx_temp;
      __ movl2ptr(rdx_stack_move, rcx_amh_conversion);
      __ sarptr(rdx_stack_move, CONV_STACK_MOVE_SHIFT);

      int argslot0_num = 0;
      Address argslot0 = __ argument_address(RegisterOrConstant(argslot0_num));
      assert(argslot0.base() == rsp, "");
      int pre_arg_size = argslot0.disp();
      assert(pre_arg_size % wordSize == 0, "");
      assert(pre_arg_size > 0, "must include PC");

      // remember the old rsp+1 (argslot[0])
      Register rbx_oldarg = rbx_temp;
      __ lea(rbx_oldarg, argslot0);

      // move rsp down to make room for dups
      __ lea(rsp, Address(rsp, rdx_stack_move, Address::times_ptr));

      // compute the new rsp+1 (argslot[0])
      Register rdx_newarg = rdx_temp;
      __ lea(rdx_newarg, argslot0);

      __ push(rdi);             // need a temp
      // (preceding push must be done after arg addresses are taken!)

      // pull down the pre_arg_size data (PC)
      for (int i = -pre_arg_size; i < 0; i += wordSize) {
        __ movptr(rdi, Address(rbx_oldarg, i));
        __ movptr(Address(rdx_newarg, i), rdi);
      }

      // copy from rax_argslot[0...] down to new_rsp[1...]
      // pseudo-code:
      //   rbx = old_rsp+1
      //   rdx = new_rsp+1
      //   rax = argslot
      //   while (rdx < rbx) *rdx++ = *rax++
      Label loop;
      __ bind(loop);
      __ movptr(rdi, Address(rax_argslot, 0));
      __ movptr(Address(rdx_newarg, 0), rdi);
      __ addptr(rax_argslot, wordSize);
      __ addptr(rdx_newarg, wordSize);
      __ cmpptr(rdx_newarg, rbx_oldarg);
      __ jccb(Assembler::less, loop);

      __ pop(rdi);              // restore temp

      __ load_heap_oop(rcx_recv, rcx_mh_vmtarget);
      __ jump_to_method_handle_entry(rcx_recv, rdx_temp);
    }
    break;

  case _adapter_drop_args:
    {
      // 'argslot' is the position of the first argument to nuke
      __ movl(rax_argslot, rcx_amh_vmargslot);
      __ lea(rax_argslot, __ argument_address(rax_argslot));

      __ push(rdi);             // need a temp
      // (must do previous push after argslot address is taken)

      // 'stack_move' is number of words to drop
      Register rdi_stack_move = rdi;
      __ movl2ptr(rdi_stack_move, rcx_amh_conversion);
      __ sarptr(rdi_stack_move, CONV_STACK_MOVE_SHIFT);
      remove_arg_slots(_masm, rdi_stack_move,
                       rax_argslot, rbx_temp, rdx_temp);

      __ pop(rdi);              // restore temp

      __ load_heap_oop(rcx_recv, rcx_mh_vmtarget);
      __ jump_to_method_handle_entry(rcx_recv, rdx_temp);
    }
    break;

  case _adapter_collect_args:
    __ unimplemented(entry_name(ek)); // %%% FIXME: NYI
    break;

  case _adapter_spread_args:
    // handled completely by optimized cases
    __ stop("init_AdapterMethodHandle should not issue this");
    break;

  case _adapter_opt_spread_0:
  case _adapter_opt_spread_1:
  case _adapter_opt_spread_more:
    {
      // spread an array out into a group of arguments
      int length_constant = get_ek_adapter_opt_spread_info(ek);

      // find the address of the array argument
      __ movl(rax_argslot, rcx_amh_vmargslot);
      __ lea(rax_argslot, __ argument_address(rax_argslot));

      // grab some temps
      { __ push(rsi); __ push(rdi); }
      // (preceding pushes must be done after argslot address is taken!)
#define UNPUSH_RSI_RDI \
      { __ pop(rdi); __ pop(rsi); }

      // arx_argslot points both to the array and to the first output arg
      vmarg = Address(rax_argslot, 0);

      // Get the array value.
      Register  rsi_array       = rsi;
      Register  rdx_array_klass = rdx_temp;
      BasicType elem_type       = T_OBJECT;
      int       length_offset   = arrayOopDesc::length_offset_in_bytes();
      int       elem0_offset    = arrayOopDesc::base_offset_in_bytes(elem_type);
      __ movptr(rsi_array, vmarg);
      Label skip_array_check;
      if (length_constant == 0) {
        __ testptr(rsi_array, rsi_array);
        __ jcc(Assembler::zero, skip_array_check);
      }
      __ null_check(rsi_array, oopDesc::klass_offset_in_bytes());
      __ load_klass(rdx_array_klass, rsi_array);

      // Check the array type.
      Register rbx_klass = rbx_temp;
      __ load_heap_oop(rbx_klass, rcx_amh_argument); // this is a Class object!
      __ load_heap_oop(rbx_klass, Address(rbx_klass, java_lang_Class::klass_offset_in_bytes()));

      Label ok_array_klass, bad_array_klass, bad_array_length;
      __ check_klass_subtype(rdx_array_klass, rbx_klass, rdi, ok_array_klass);
      // If we get here, the type check failed!
      __ jmp(bad_array_klass);
      __ bind(ok_array_klass);

      // Check length.
      if (length_constant >= 0) {
        __ cmpl(Address(rsi_array, length_offset), length_constant);
      } else {
        Register rbx_vminfo = rbx_temp;
        __ movl(rbx_vminfo, rcx_amh_conversion);
        assert(CONV_VMINFO_SHIFT == 0, "preshifted");
        __ andl(rbx_vminfo, CONV_VMINFO_MASK);
        __ cmpl(rbx_vminfo, Address(rsi_array, length_offset));
      }
      __ jcc(Assembler::notEqual, bad_array_length);

      Register rdx_argslot_limit = rdx_temp;

      // Array length checks out.  Now insert any required stack slots.
      if (length_constant == -1) {
        // Form a pointer to the end of the affected region.
        __ lea(rdx_argslot_limit, Address(rax_argslot, Interpreter::stackElementSize));
        // 'stack_move' is negative number of words to insert
        Register rdi_stack_move = rdi;
        __ movl2ptr(rdi_stack_move, rcx_amh_conversion);
        __ sarptr(rdi_stack_move, CONV_STACK_MOVE_SHIFT);
        Register rsi_temp = rsi_array;  // spill this
        insert_arg_slots(_masm, rdi_stack_move, -1,
                         rax_argslot, rbx_temp, rsi_temp);
        // reload the array (since rsi was killed)
        __ movptr(rsi_array, vmarg);
      } else if (length_constant > 1) {
        int arg_mask = 0;
        int new_slots = (length_constant - 1);
        for (int i = 0; i < new_slots; i++) {
          arg_mask <<= 1;
          arg_mask |= _INSERT_REF_MASK;
        }
        insert_arg_slots(_masm, new_slots * stack_move_unit(), arg_mask,
                         rax_argslot, rbx_temp, rdx_temp);
      } else if (length_constant == 1) {
        // no stack resizing required
      } else if (length_constant == 0) {
        remove_arg_slots(_masm, -stack_move_unit(),
                         rax_argslot, rbx_temp, rdx_temp);
      }

      // Copy from the array to the new slots.
      // Note: Stack change code preserves integrity of rax_argslot pointer.
      // So even after slot insertions, rax_argslot still points to first argument.
      if (length_constant == -1) {
        // [rax_argslot, rdx_argslot_limit) is the area we are inserting into.
        Register rsi_source = rsi_array;
        __ lea(rsi_source, Address(rsi_array, elem0_offset));
        Label loop;
        __ bind(loop);
        __ movptr(rbx_temp, Address(rsi_source, 0));
        __ movptr(Address(rax_argslot, 0), rbx_temp);
        __ addptr(rsi_source, type2aelembytes(elem_type));
        __ addptr(rax_argslot, Interpreter::stackElementSize);
        __ cmpptr(rax_argslot, rdx_argslot_limit);
        __ jccb(Assembler::less, loop);
      } else if (length_constant == 0) {
        __ bind(skip_array_check);
        // nothing to copy
      } else {
        int elem_offset = elem0_offset;
        int slot_offset = 0;
        for (int index = 0; index < length_constant; index++) {
          __ movptr(rbx_temp, Address(rsi_array, elem_offset));
          __ movptr(Address(rax_argslot, slot_offset), rbx_temp);
          elem_offset += type2aelembytes(elem_type);
           slot_offset += Interpreter::stackElementSize;
        }
      }

      // Arguments are spread.  Move to next method handle.
      UNPUSH_RSI_RDI;
      __ load_heap_oop(rcx_recv, rcx_mh_vmtarget);
      __ jump_to_method_handle_entry(rcx_recv, rdx_temp);

      __ bind(bad_array_klass);
      UNPUSH_RSI_RDI;
      __ pushptr(Address(rdx_array_klass, java_mirror_offset)); // required type
      __ pushptr(vmarg);                // bad array
      __ push((int)Bytecodes::_aaload); // who is complaining?
      __ jump(ExternalAddress(from_interpreted_entry(_raise_exception)));

      __ bind(bad_array_length);
      UNPUSH_RSI_RDI;
      __ push(rcx_recv);        // AMH requiring a certain length
      __ pushptr(vmarg);        // bad array
      __ push((int)Bytecodes::_arraylength); // who is complaining?
      __ jump(ExternalAddress(from_interpreted_entry(_raise_exception)));

#undef UNPUSH_RSI_RDI
    }
    break;

  case _adapter_flyby:
  case _adapter_ricochet:
    __ unimplemented(entry_name(ek)); // %%% FIXME: NYI
    break;

  default:  ShouldNotReachHere();
  }
  __ hlt();

  address me_cookie = MethodHandleEntry::start_compiled_entry(_masm, interp_entry);
  __ unimplemented(entry_name(ek)); // %%% FIXME: NYI

  init_entry(ek, MethodHandleEntry::finish_compiled_entry(_masm, me_cookie));
}