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 /*

  * Copyright (c) 2003, 2012, 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_sparc.inline.hpp"

 #include "code/debugInfoRec.hpp"

 #include "code/icBuffer.hpp"

 #include "code/vtableStubs.hpp"

 #include "interpreter/interpreter.hpp"

 #include "oops/compiledICHolder.hpp"

 #include "prims/jvmtiRedefineClassesTrace.hpp"

 #include "runtime/sharedRuntime.hpp"

 #include "runtime/vframeArray.hpp"

 #include "vmreg_sparc.inline.hpp"

 #ifdef COMPILER1

 #include "c1/c1_Runtime1.hpp"

 #endif

 #ifdef COMPILER2

 #include "opto/runtime.hpp"

 #endif

 #ifdef SHARK

 #include "compiler/compileBroker.hpp"

 #include "shark/sharkCompiler.hpp"

 #endif

 #define __ masm->

 class RegisterSaver {

   // Used for saving volatile registers. This is Gregs, Fregs, I/L/O.

   // The Oregs are problematic. In the 32bit build the compiler can

   // have O registers live with 64 bit quantities. A window save will

   // cut the heads off of the registers. We have to do a very extensive

   // stack dance to save and restore these properly.

   // Note that the Oregs problem only exists if we block at either a polling

   // page exception a compiled code safepoint that was not originally a call

   // or deoptimize following one of these kinds of safepoints.

   // Lots of registers to save.  For all builds, a window save will preserve

   // the %i and %l registers.  For the 32-bit longs-in-two entries and 64-bit

   // builds a window-save will preserve the %o registers.  In the LION build

   // we need to save the 64-bit %o registers which requires we save them

   // before the window-save (as then they become %i registers and get their

   // heads chopped off on interrupt).  We have to save some %g registers here

   // as well.

   enum {

     // This frame's save area.  Includes extra space for the native call:

     // vararg's layout space and the like.  Briefly holds the caller's

     // register save area.

     call_args_area = frame::register_save_words_sp_offset +

                      frame::memory_parameter_word_sp_offset*wordSize,

     // Make sure save locations are always 8 byte aligned.

     // can't use round_to because it doesn't produce compile time constant

     start_of_extra_save_area = ((call_args_area + 7) & ~7),

     g1_offset = start_of_extra_save_area, // g-regs needing saving

     g3_offset = g1_offset+8,

     g4_offset = g3_offset+8,

     g5_offset = g4_offset+8,

     o0_offset = g5_offset+8,

     o1_offset = o0_offset+8,

     o2_offset = o1_offset+8,

     o3_offset = o2_offset+8,

     o4_offset = o3_offset+8,

     o5_offset = o4_offset+8,

     start_of_flags_save_area = o5_offset+8,

     ccr_offset = start_of_flags_save_area,

     fsr_offset = ccr_offset + 8,

     d00_offset = fsr_offset+8,  // Start of float save area

     register_save_size = d00_offset+8*32

   };

   public:

   static int Oexception_offset() { return o0_offset; };

   static int G3_offset() { return g3_offset; };

   static int G5_offset() { return g5_offset; };

   static OopMap* save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words);

   static void restore_live_registers(MacroAssembler* masm);

   // During deoptimization only the result register need to be restored

   // all the other values have already been extracted.

   static void restore_result_registers(MacroAssembler* masm);

 };

 OopMap* RegisterSaver::save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words) {

   // Record volatile registers as callee-save values in an OopMap so their save locations will be

   // propagated to the caller frame's RegisterMap during StackFrameStream construction (needed for

   // deoptimization; see compiledVFrame::create_stack_value).  The caller's I, L and O registers

   // are saved in register windows - I's and L's in the caller's frame and O's in the stub frame

   // (as the stub's I's) when the runtime routine called by the stub creates its frame.

   int i;

   // Always make the frame size 16 byte aligned.

   int frame_size = round_to(additional_frame_words + register_save_size, 16);

   // OopMap frame size is in c2 stack slots (sizeof(jint)) not bytes or words

   int frame_size_in_slots = frame_size / sizeof(jint);

   // CodeBlob frame size is in words.

   *total_frame_words = frame_size / wordSize;

   // OopMap* map = new OopMap(*total_frame_words, 0);

   OopMap* map = new OopMap(frame_size_in_slots, 0);

 #if !defined(_LP64)

   // Save 64-bit O registers; they will get their heads chopped off on a 'save'.

   __ stx(O0, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+0*8);

   __ stx(O1, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+1*8);

   __ stx(O2, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+2*8);

   __ stx(O3, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+3*8);

   __ stx(O4, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+4*8);

   __ stx(O5, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+5*8);

 #endif /* _LP64 */

   __ save(SP, -frame_size, SP);

 #ifndef _LP64

   // Reload the 64 bit Oregs. Although they are now Iregs we load them

   // to Oregs here to avoid interrupts cutting off their heads

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+0*8, O0);

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+1*8, O1);

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+2*8, O2);

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+3*8, O3);

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+4*8, O4);

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+5*8, O5);

   __ stx(O0, SP, o0_offset+STACK_BIAS);

   map->set_callee_saved(VMRegImpl::stack2reg((o0_offset + 4)>>2), O0->as_VMReg());

   __ stx(O1, SP, o1_offset+STACK_BIAS);

   map->set_callee_saved(VMRegImpl::stack2reg((o1_offset + 4)>>2), O1->as_VMReg());

   __ stx(O2, SP, o2_offset+STACK_BIAS);

   map->set_callee_saved(VMRegImpl::stack2reg((o2_offset + 4)>>2), O2->as_VMReg());

   __ stx(O3, SP, o3_offset+STACK_BIAS);

   map->set_callee_saved(VMRegImpl::stack2reg((o3_offset + 4)>>2), O3->as_VMReg());

   __ stx(O4, SP, o4_offset+STACK_BIAS);

   map->set_callee_saved(VMRegImpl::stack2reg((o4_offset + 4)>>2), O4->as_VMReg());

   __ stx(O5, SP, o5_offset+STACK_BIAS);

   map->set_callee_saved(VMRegImpl::stack2reg((o5_offset + 4)>>2), O5->as_VMReg());

 #endif /* _LP64 */

 #ifdef _LP64

   int debug_offset = 0;

 #else

   int debug_offset = 4;

 #endif

   // Save the G's

   __ stx(G1, SP, g1_offset+STACK_BIAS);

   map->set_callee_saved(VMRegImpl::stack2reg((g1_offset + debug_offset)>>2), G1->as_VMReg());

   __ stx(G3, SP, g3_offset+STACK_BIAS);

   map->set_callee_saved(VMRegImpl::stack2reg((g3_offset + debug_offset)>>2), G3->as_VMReg());

   __ stx(G4, SP, g4_offset+STACK_BIAS);

   map->set_callee_saved(VMRegImpl::stack2reg((g4_offset + debug_offset)>>2), G4->as_VMReg());

   __ stx(G5, SP, g5_offset+STACK_BIAS);

   map->set_callee_saved(VMRegImpl::stack2reg((g5_offset + debug_offset)>>2), G5->as_VMReg());

   // This is really a waste but we'll keep things as they were for now

   if (true) {

 #ifndef _LP64

     map->set_callee_saved(VMRegImpl::stack2reg((o0_offset)>>2), O0->as_VMReg()->next());

     map->set_callee_saved(VMRegImpl::stack2reg((o1_offset)>>2), O1->as_VMReg()->next());

     map->set_callee_saved(VMRegImpl::stack2reg((o2_offset)>>2), O2->as_VMReg()->next());

     map->set_callee_saved(VMRegImpl::stack2reg((o3_offset)>>2), O3->as_VMReg()->next());

     map->set_callee_saved(VMRegImpl::stack2reg((o4_offset)>>2), O4->as_VMReg()->next());

     map->set_callee_saved(VMRegImpl::stack2reg((o5_offset)>>2), O5->as_VMReg()->next());

     map->set_callee_saved(VMRegImpl::stack2reg((g1_offset)>>2), G1->as_VMReg()->next());

     map->set_callee_saved(VMRegImpl::stack2reg((g3_offset)>>2), G3->as_VMReg()->next());

     map->set_callee_saved(VMRegImpl::stack2reg((g4_offset)>>2), G4->as_VMReg()->next());

     map->set_callee_saved(VMRegImpl::stack2reg((g5_offset)>>2), G5->as_VMReg()->next());

 #endif /* _LP64 */

   }

   // Save the flags

   __ rdccr( G5 );

   __ stx(G5, SP, ccr_offset+STACK_BIAS);

   __ stxfsr(SP, fsr_offset+STACK_BIAS);

   // Save all the FP registers: 32 doubles (32 floats correspond to the 2 halves of the first 16 doubles)

   int offset = d00_offset;

   for( int i=0; i<FloatRegisterImpl::number_of_registers; i+=2 ) {

     FloatRegister f = as_FloatRegister(i);

     __ stf(FloatRegisterImpl::D,  f, SP, offset+STACK_BIAS);

     // Record as callee saved both halves of double registers (2 float registers).

     map->set_callee_saved(VMRegImpl::stack2reg(offset>>2), f->as_VMReg());

     map->set_callee_saved(VMRegImpl::stack2reg((offset + sizeof(float))>>2), f->as_VMReg()->next());

     offset += sizeof(double);

   }

   // And we're done.

   return map;

 }

 // Pop the current frame and restore all the registers that we

 // saved.

 void RegisterSaver::restore_live_registers(MacroAssembler* masm) {

   // Restore all the FP registers

   for( int i=0; i<FloatRegisterImpl::number_of_registers; i+=2 ) {

     __ ldf(FloatRegisterImpl::D, SP, d00_offset+i*sizeof(float)+STACK_BIAS, as_FloatRegister(i));

   }

   __ ldx(SP, ccr_offset+STACK_BIAS, G1);

   __ wrccr (G1) ;

   // Restore the G's

   // Note that G2 (AKA GThread) must be saved and restored separately.

   // TODO-FIXME: save and restore some of the other ASRs, viz., %asi and %gsr.

   __ ldx(SP, g1_offset+STACK_BIAS, G1);

   __ ldx(SP, g3_offset+STACK_BIAS, G3);

   __ ldx(SP, g4_offset+STACK_BIAS, G4);

   __ ldx(SP, g5_offset+STACK_BIAS, G5);

 #if !defined(_LP64)

   // Restore the 64-bit O's.

   __ ldx(SP, o0_offset+STACK_BIAS, O0);

   __ ldx(SP, o1_offset+STACK_BIAS, O1);

   __ ldx(SP, o2_offset+STACK_BIAS, O2);

   __ ldx(SP, o3_offset+STACK_BIAS, O3);

   __ ldx(SP, o4_offset+STACK_BIAS, O4);

   __ ldx(SP, o5_offset+STACK_BIAS, O5);

   // And temporarily place them in TLS

   __ stx(O0, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+0*8);

   __ stx(O1, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+1*8);

   __ stx(O2, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+2*8);

   __ stx(O3, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+3*8);

   __ stx(O4, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+4*8);

   __ stx(O5, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+5*8);

 #endif /* _LP64 */

   // Restore flags

   __ ldxfsr(SP, fsr_offset+STACK_BIAS);

   __ restore();

 #if !defined(_LP64)

   // Now reload the 64bit Oregs after we've restore the window.

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+0*8, O0);

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+1*8, O1);

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+2*8, O2);

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+3*8, O3);

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+4*8, O4);

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+5*8, O5);

 #endif /* _LP64 */

 }

 // Pop the current frame and restore the registers that might be holding

 // a result.

 void RegisterSaver::restore_result_registers(MacroAssembler* masm) {

 #if !defined(_LP64)

   // 32bit build returns longs in G1

   __ ldx(SP, g1_offset+STACK_BIAS, G1);

   // Retrieve the 64-bit O's.

   __ ldx(SP, o0_offset+STACK_BIAS, O0);

   __ ldx(SP, o1_offset+STACK_BIAS, O1);

   // and save to TLS

   __ stx(O0, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+0*8);

   __ stx(O1, G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+1*8);

 #endif /* _LP64 */

   __ ldf(FloatRegisterImpl::D, SP, d00_offset+STACK_BIAS, as_FloatRegister(0));

   __ restore();

 #if !defined(_LP64)

   // Now reload the 64bit Oregs after we've restore the window.

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+0*8, O0);

   __ ldx(G2_thread, JavaThread::o_reg_temps_offset_in_bytes()+1*8, O1);

 #endif /* _LP64 */

 }

 // The java_calling_convention describes stack locations as ideal slots on

 // a frame with no abi restrictions. Since we must observe abi restrictions

 // (like the placement of the register window) the slots must be biased by

 // the following value.

 static int reg2offset(VMReg r) {

   return (r->reg2stack() + SharedRuntime::out_preserve_stack_slots()) * VMRegImpl::stack_slot_size;

 }

 static VMRegPair reg64_to_VMRegPair(Register r) {

   VMRegPair ret;

   if (wordSize == 8) {

     ret.set2(r->as_VMReg());

   } else {

     ret.set_pair(r->successor()->as_VMReg(), r->as_VMReg());

   }

   return ret;

 }

 // ---------------------------------------------------------------------------

 // Read the array of BasicTypes from a signature, and compute where the

 // arguments should go.  Values in the VMRegPair regs array refer to 4-byte (VMRegImpl::stack_slot_size)

 // quantities.  Values less than VMRegImpl::stack0 are registers, those above

 // refer to 4-byte stack slots.  All stack slots are based off of the window

 // top.  VMRegImpl::stack0 refers to the first slot past the 16-word window,

 // and VMRegImpl::stack0+1 refers to the memory word 4-byes higher.  Register

 // values 0-63 (up to RegisterImpl::number_of_registers) are the 64-bit

 // integer registers.  Values 64-95 are the (32-bit only) float registers.

 // Each 32-bit quantity is given its own number, so the integer registers

 // (in either 32- or 64-bit builds) use 2 numbers.  For example, there is

 // an O0-low and an O0-high.  Essentially, all int register numbers are doubled.

 // Register results are passed in O0-O5, for outgoing call arguments.  To

 // convert to incoming arguments, convert all O's to I's.  The regs array

 // refer to the low and hi 32-bit words of 64-bit registers or stack slots.

 // If the regs[].second() field is set to VMRegImpl::Bad(), it means it's unused (a

 // 32-bit value was passed).  If both are VMRegImpl::Bad(), it means no value was

 // passed (used as a placeholder for the other half of longs and doubles in

 // the 64-bit build).  regs[].second() is either VMRegImpl::Bad() or regs[].second() is

 // regs[].first()+1 (regs[].first() may be misaligned in the C calling convention).

 // Sparc never passes a value in regs[].second() but not regs[].first() (regs[].first()

 // == VMRegImpl::Bad() && regs[].second() != VMRegImpl::Bad()) nor unrelated values in the

 // same VMRegPair.

 // Note: the INPUTS in sig_bt are in units of Java argument words, which are

 // either 32-bit or 64-bit depending on the build.  The OUTPUTS are in 32-bit

 // units regardless of build.

 // ---------------------------------------------------------------------------

 // The compiled Java calling convention.  The Java convention always passes

 // 64-bit values in adjacent aligned locations (either registers or stack),

 // floats in float registers and doubles in aligned float pairs.  There is

 // no backing varargs store for values in registers.

 // In the 32-bit build, longs are passed on the stack (cannot be

 // passed in I's, because longs in I's get their heads chopped off at

 // interrupt).

 int SharedRuntime::java_calling_convention(const BasicType *sig_bt,

                                            VMRegPair *regs,

                                            int total_args_passed,

                                            int is_outgoing) {

   assert(F31->as_VMReg()->is_reg(), "overlapping stack/register numbers");

   const int int_reg_max = SPARC_ARGS_IN_REGS_NUM;

   const int flt_reg_max = 8;

   int int_reg = 0;

   int flt_reg = 0;

   int slot = 0;

   for (int i = 0; i < total_args_passed; i++) {

     switch (sig_bt[i]) {

     case T_INT:

     case T_SHORT:

     case T_CHAR:

     case T_BYTE:

     case T_BOOLEAN:

 #ifndef _LP64

     case T_OBJECT:

     case T_ARRAY:

     case T_ADDRESS: // Used, e.g., in slow-path locking for the lock's stack address

 #endif // _LP64

       if (int_reg < int_reg_max) {

         Register r = is_outgoing ? as_oRegister(int_reg++) : as_iRegister(int_reg++);

         regs[i].set1(r->as_VMReg());

       } else {

         regs[i].set1(VMRegImpl::stack2reg(slot++));

       }

       break;

 #ifdef _LP64

     case T_LONG:

       assert(sig_bt[i+1] == T_VOID, "expecting VOID in other half");

       // fall-through

     case T_OBJECT:

     case T_ARRAY:

     case T_ADDRESS: // Used, e.g., in slow-path locking for the lock's stack address

       if (int_reg < int_reg_max) {

         Register r = is_outgoing ? as_oRegister(int_reg++) : as_iRegister(int_reg++);

         regs[i].set2(r->as_VMReg());

       } else {

         slot = round_to(slot, 2);  // align

         regs[i].set2(VMRegImpl::stack2reg(slot));

         slot += 2;

       }

       break;

 #else

     case T_LONG:

       assert(sig_bt[i+1] == T_VOID, "expecting VOID in other half");

       // On 32-bit SPARC put longs always on the stack to keep the pressure off

       // integer argument registers.  They should be used for oops.

       slot = round_to(slot, 2);  // align

       regs[i].set2(VMRegImpl::stack2reg(slot));

       slot += 2;

 #endif

       break;

     case T_FLOAT:

       if (flt_reg < flt_reg_max) {

         FloatRegister r = as_FloatRegister(flt_reg++);

         regs[i].set1(r->as_VMReg());

       } else {

         regs[i].set1(VMRegImpl::stack2reg(slot++));

       }

       break;

     case T_DOUBLE:

       assert(sig_bt[i+1] == T_VOID, "expecting half");

       if (round_to(flt_reg, 2) + 1 < flt_reg_max) {

         flt_reg = round_to(flt_reg, 2);  // align

         FloatRegister r = as_FloatRegister(flt_reg);

         regs[i].set2(r->as_VMReg());

         flt_reg += 2;

       } else {

         slot = round_to(slot, 2);  // align

         regs[i].set2(VMRegImpl::stack2reg(slot));

         slot += 2;

       }

       break;

     case T_VOID:

       regs[i].set_bad();   // Halves of longs & doubles

       break;

     default:

       fatal(err_msg_res("unknown basic type %d", sig_bt[i]));

       break;

     }

   }

   // retun the amount of stack space these arguments will need.

   return slot;

 }

 // Helper class mostly to avoid passing masm everywhere, and handle

 // store displacement overflow logic.

 class AdapterGenerator {

   MacroAssembler *masm;

   Register Rdisp;

   void set_Rdisp(Register r)  { Rdisp = r; }

   void patch_callers_callsite();

   // base+st_off points to top of argument

   int arg_offset(const int st_off) { return st_off; }

   int next_arg_offset(const int st_off) {

     return st_off - Interpreter::stackElementSize;

   }

   // Argument slot values may be loaded first into a register because

   // they might not fit into displacement.

   RegisterOrConstant arg_slot(const int st_off);

   RegisterOrConstant next_arg_slot(const int st_off);

   // Stores long into offset pointed to by base

   void store_c2i_long(Register r, Register base,

                       const int st_off, bool is_stack);

   void store_c2i_object(Register r, Register base,

                         const int st_off);

   void store_c2i_int(Register r, Register base,

                      const int st_off);

   void store_c2i_double(VMReg r_2,

                         VMReg r_1, Register base, const int st_off);

   void store_c2i_float(FloatRegister f, Register base,

                        const int st_off);

  public:

   void gen_c2i_adapter(int total_args_passed,

                               // VMReg max_arg,

                               int comp_args_on_stack, // VMRegStackSlots

                               const BasicType *sig_bt,

                               const VMRegPair *regs,

                               Label& skip_fixup);

   void gen_i2c_adapter(int total_args_passed,

                               // VMReg max_arg,

                               int comp_args_on_stack, // VMRegStackSlots

                               const BasicType *sig_bt,

                               const VMRegPair *regs);

   AdapterGenerator(MacroAssembler *_masm) : masm(_masm) {}

 };

 // Patch the callers callsite with entry to compiled code if it exists.

 void AdapterGenerator::patch_callers_callsite() {

   Label L;

   __ ld_ptr(G5_method, in_bytes(Method::code_offset()), G3_scratch);

   __ br_null(G3_scratch, false, Assembler::pt, L);

   __ delayed()->nop();

   // Call into the VM to patch the caller, then jump to compiled callee

   __ save_frame(4);     // Args in compiled layout; do not blow them

   // Must save all the live Gregs the list is:

   // G1: 1st Long arg (32bit build)

   // G2: global allocated to TLS

   // G3: used in inline cache check (scratch)

   // G4: 2nd Long arg (32bit build);

   // G5: used in inline cache check (Method*)

   // The longs must go to the stack by hand since in the 32 bit build they can be trashed by window ops.

 #ifdef _LP64

   // mov(s,d)

   __ mov(G1, L1);

   __ mov(G4, L4);

   __ mov(G5_method, L5);

   __ mov(G5_method, O0);         // VM needs target method

   __ mov(I7, O1);                // VM needs caller's callsite

   // Must be a leaf call...

   // can be very far once the blob has been relocated

   AddressLiteral dest(CAST_FROM_FN_PTR(address, SharedRuntime::fixup_callers_callsite));

   __ relocate(relocInfo::runtime_call_type);

   __ jumpl_to(dest, O7, O7);

   __ delayed()->mov(G2_thread, L7_thread_cache);

   __ mov(L7_thread_cache, G2_thread);

   __ mov(L1, G1);

   __ mov(L4, G4);

   __ mov(L5, G5_method);

 #else

   __ stx(G1, FP, -8 + STACK_BIAS);

   __ stx(G4, FP, -16 + STACK_BIAS);

   __ mov(G5_method, L5);

   __ mov(G5_method, O0);         // VM needs target method

   __ mov(I7, O1);                // VM needs caller's callsite

   // Must be a leaf call...

   __ call(CAST_FROM_FN_PTR(address, SharedRuntime::fixup_callers_callsite), relocInfo::runtime_call_type);

   __ delayed()->mov(G2_thread, L7_thread_cache);

   __ mov(L7_thread_cache, G2_thread);

   __ ldx(FP, -8 + STACK_BIAS, G1);

   __ ldx(FP, -16 + STACK_BIAS, G4);

   __ mov(L5, G5_method);

 #endif /* _LP64 */

   __ restore();      // Restore args

   __ bind(L);

 }

 RegisterOrConstant AdapterGenerator::arg_slot(const int st_off) {

   RegisterOrConstant roc(arg_offset(st_off));

   return __ ensure_simm13_or_reg(roc, Rdisp);

 }

 RegisterOrConstant AdapterGenerator::next_arg_slot(const int st_off) {

   RegisterOrConstant roc(next_arg_offset(st_off));

   return __ ensure_simm13_or_reg(roc, Rdisp);

 }

 // Stores long into offset pointed to by base

 void AdapterGenerator::store_c2i_long(Register r, Register base,

                                       const int st_off, bool is_stack) {

 #ifdef _LP64

   // In V9, longs are given 2 64-bit slots in the interpreter, but the

   // data is passed in only 1 slot.

   __ stx(r, base, next_arg_slot(st_off));

 #else

 #ifdef COMPILER2

   // Misaligned store of 64-bit data

   __ stw(r, base, arg_slot(st_off));    // lo bits

   __ srlx(r, 32, r);

   __ stw(r, base, next_arg_slot(st_off));  // hi bits

 #else

   if (is_stack) {

     // Misaligned store of 64-bit data

     __ stw(r, base, arg_slot(st_off));    // lo bits

     __ srlx(r, 32, r);

     __ stw(r, base, next_arg_slot(st_off));  // hi bits

   } else {

     __ stw(r->successor(), base, arg_slot(st_off)     ); // lo bits

     __ stw(r             , base, next_arg_slot(st_off)); // hi bits

   }

 #endif // COMPILER2

 #endif // _LP64

 }

 void AdapterGenerator::store_c2i_object(Register r, Register base,

                       const int st_off) {

   __ st_ptr (r, base, arg_slot(st_off));

 }

 void AdapterGenerator::store_c2i_int(Register r, Register base,

                    const int st_off) {

   __ st (r, base, arg_slot(st_off));

 }

 // Stores into offset pointed to by base

 void AdapterGenerator::store_c2i_double(VMReg r_2,

                       VMReg r_1, Register base, const int st_off) {

 #ifdef _LP64

   // In V9, doubles are given 2 64-bit slots in the interpreter, but the

   // data is passed in only 1 slot.

   __ stf(FloatRegisterImpl::D, r_1->as_FloatRegister(), base, next_arg_slot(st_off));

 #else

   // Need to marshal 64-bit value from misaligned Lesp loads

   __ stf(FloatRegisterImpl::S, r_1->as_FloatRegister(), base, next_arg_slot(st_off));

   __ stf(FloatRegisterImpl::S, r_2->as_FloatRegister(), base, arg_slot(st_off) );

 #endif

 }

 void AdapterGenerator::store_c2i_float(FloatRegister f, Register base,

                                        const int st_off) {

   __ stf(FloatRegisterImpl::S, f, base, arg_slot(st_off));

 }

 void AdapterGenerator::gen_c2i_adapter(

                             int total_args_passed,

                             // VMReg max_arg,

                             int comp_args_on_stack, // VMRegStackSlots

                             const BasicType *sig_bt,

                             const VMRegPair *regs,

                             Label& L_skip_fixup) {

   // Before we get into the guts of the C2I adapter, see if we should be here

   // at all.  We've come from compiled code and are attempting to jump to the

   // interpreter, which means the caller made a static call to get here

   // (vcalls always get a compiled target if there is one).  Check for a

   // compiled target.  If there is one, we need to patch the caller's call.

   // However we will run interpreted if we come thru here. The next pass

   // thru the call site will run compiled. If we ran compiled here then

   // we can (theorectically) do endless i2c->c2i->i2c transitions during

   // deopt/uncommon trap cycles. If we always go interpreted here then

   // we can have at most one and don't need to play any tricks to keep

   // from endlessly growing the stack.

   //

   // Actually if we detected that we had an i2c->c2i transition here we

   // ought to be able to reset the world back to the state of the interpreted

   // call and not bother building another interpreter arg area. We don't

   // do that at this point.

   patch_callers_callsite();

   __ bind(L_skip_fixup);

   // Since all args are passed on the stack, total_args_passed*wordSize is the

   // space we need.  Add in varargs area needed by the interpreter. Round up

   // to stack alignment.

   const int arg_size = total_args_passed * Interpreter::stackElementSize;

   const int varargs_area =

                  (frame::varargs_offset - frame::register_save_words)*wordSize;

   const int extraspace = round_to(arg_size + varargs_area, 2*wordSize);

   const int bias = STACK_BIAS;

   const int interp_arg_offset = frame::varargs_offset*wordSize +

                         (total_args_passed-1)*Interpreter::stackElementSize;

   const Register base = SP;

   // Make some extra space on the stack.

   __ sub(SP, __ ensure_simm13_or_reg(extraspace, G3_scratch), SP);

   set_Rdisp(G3_scratch);

   // Write the args into the outgoing interpreter space.

   for (int i = 0; i < total_args_passed; i++) {

     const int st_off = interp_arg_offset - (i*Interpreter::stackElementSize) + bias;

     VMReg r_1 = regs[i].first();

     VMReg r_2 = regs[i].second();

     if (!r_1->is_valid()) {

       assert(!r_2->is_valid(), "");

       continue;

     }

     if (r_1->is_stack()) {        // Pretend stack targets are loaded into G1

       RegisterOrConstant ld_off = reg2offset(r_1) + extraspace + bias;

       ld_off = __ ensure_simm13_or_reg(ld_off, Rdisp);

       r_1 = G1_scratch->as_VMReg();// as part of the load/store shuffle

       if (!r_2->is_valid()) __ ld (base, ld_off, G1_scratch);

       else                  __ ldx(base, ld_off, G1_scratch);

     }

     if (r_1->is_Register()) {

       Register r = r_1->as_Register()->after_restore();

       if (sig_bt[i] == T_OBJECT || sig_bt[i] == T_ARRAY) {

         store_c2i_object(r, base, st_off);

       } else if (sig_bt[i] == T_LONG || sig_bt[i] == T_DOUBLE) {

         store_c2i_long(r, base, st_off, r_2->is_stack());

       } else {

         store_c2i_int(r, base, st_off);

       }

     } else {

       assert(r_1->is_FloatRegister(), "");

       if (sig_bt[i] == T_FLOAT) {

         store_c2i_float(r_1->as_FloatRegister(), base, st_off);

       } else {

         assert(sig_bt[i] == T_DOUBLE, "wrong type");

         store_c2i_double(r_2, r_1, base, st_off);

       }

     }

   }

   // Load the interpreter entry point.

   __ ld_ptr(G5_method, in_bytes(Method::interpreter_entry_offset()), G3_scratch);

   // Pass O5_savedSP as an argument to the interpreter.

   // The interpreter will restore SP to this value before returning.

   __ add(SP, __ ensure_simm13_or_reg(extraspace, G1), O5_savedSP);

   __ mov((frame::varargs_offset)*wordSize -

          1*Interpreter::stackElementSize+bias+BytesPerWord, G1);

   // Jump to the interpreter just as if interpreter was doing it.

   __ jmpl(G3_scratch, 0, G0);

   // Setup Lesp for the call.  Cannot actually set Lesp as the current Lesp

   // (really L0) is in use by the compiled frame as a generic temp.  However,

   // the interpreter does not know where its args are without some kind of

   // arg pointer being passed in.  Pass it in Gargs.

   __ delayed()->add(SP, G1, Gargs);

 }

 static void range_check(MacroAssembler* masm, Register pc_reg, Register temp_reg, Register temp2_reg,

                         address code_start, address code_end,

                         Label& L_ok) {

   Label L_fail;

   __ set(ExternalAddress(code_start), temp_reg);

   __ set(pointer_delta(code_end, code_start, 1), temp2_reg);

   __ cmp(pc_reg, temp_reg);

   __ brx(Assembler::lessEqualUnsigned, false, Assembler::pn, L_fail);

   __ delayed()->add(temp_reg, temp2_reg, temp_reg);

   __ cmp(pc_reg, temp_reg);

   __ cmp_and_brx_short(pc_reg, temp_reg, Assembler::lessUnsigned, Assembler::pt, L_ok);

   __ bind(L_fail);

 }

 void AdapterGenerator::gen_i2c_adapter(

                             int total_args_passed,

                             // VMReg max_arg,

                             int comp_args_on_stack, // VMRegStackSlots

                             const BasicType *sig_bt,

                             const VMRegPair *regs) {

   // Generate an I2C adapter: adjust the I-frame to make space for the C-frame

   // layout.  Lesp was saved by the calling I-frame and will be restored on

   // return.  Meanwhile, outgoing arg space is all owned by the callee

   // C-frame, so we can mangle it at will.  After adjusting the frame size,

   // hoist register arguments and repack other args according to the compiled

   // code convention.  Finally, end in a jump to the compiled code.  The entry

   // point address is the start of the buffer.

   // We will only enter here from an interpreted frame and never from after

   // passing thru a c2i. Azul allowed this but we do not. If we lose the

   // race and use a c2i we will remain interpreted for the race loser(s).

   // This removes all sorts of headaches on the x86 side and also eliminates

   // the possibility of having c2i -> i2c -> c2i -> ... endless transitions.

   // More detail:

   // Adapters can be frameless because they do not require the caller

   // to perform additional cleanup work, such as correcting the stack pointer.

   // An i2c adapter is frameless because the *caller* frame, which is interpreted,

   // routinely repairs its own stack pointer (from interpreter_frame_last_sp),

   // even if a callee has modified the stack pointer.

   // A c2i adapter is frameless because the *callee* frame, which is interpreted,

   // routinely repairs its caller's stack pointer (from sender_sp, which is set

   // up via the senderSP register).

   // In other words, if *either* the caller or callee is interpreted, we can

   // get the stack pointer repaired after a call.

   // This is why c2i and i2c adapters cannot be indefinitely composed.

   // In particular, if a c2i adapter were to somehow call an i2c adapter,

   // both caller and callee would be compiled methods, and neither would

   // clean up the stack pointer changes performed by the two adapters.

   // If this happens, control eventually transfers back to the compiled

   // caller, but with an uncorrected stack, causing delayed havoc.

   if (VerifyAdapterCalls &&

       (Interpreter::code() != NULL || StubRoutines::code1() != NULL)) {

     // So, let's test for cascading c2i/i2c adapters right now.

     //  assert(Interpreter::contains($return_addr) ||

     //         StubRoutines::contains($return_addr),

     //         "i2c adapter must return to an interpreter frame");

     __ block_comment("verify_i2c { ");

     Label L_ok;

     if (Interpreter::code() != NULL)

       range_check(masm, O7, O0, O1,

                   Interpreter::code()->code_start(), Interpreter::code()->code_end(),

                   L_ok);

     if (StubRoutines::code1() != NULL)

       range_check(masm, O7, O0, O1,

                   StubRoutines::code1()->code_begin(), StubRoutines::code1()->code_end(),

                   L_ok);

     if (StubRoutines::code2() != NULL)

       range_check(masm, O7, O0, O1,

                   StubRoutines::code2()->code_begin(), StubRoutines::code2()->code_end(),

                   L_ok);

     const char* msg = "i2c adapter must return to an interpreter frame";

     __ block_comment(msg);

     __ stop(msg);

     __ bind(L_ok);

     __ block_comment("} verify_i2ce ");

   }

   // As you can see from the list of inputs & outputs there are not a lot

   // of temp registers to work with: mostly G1, G3 & G4.

   // Inputs:

   // G2_thread      - TLS

   // G5_method      - Method oop

   // G4 (Gargs)     - Pointer to interpreter's args

   // O0..O4         - free for scratch

   // O5_savedSP     - Caller's saved SP, to be restored if needed

   // O6             - Current SP!

   // O7             - Valid return address

   // L0-L7, I0-I7   - Caller's temps (no frame pushed yet)

   // Outputs:

   // G2_thread      - TLS

   // O0-O5          - Outgoing args in compiled layout

   // O6             - Adjusted or restored SP

   // O7             - Valid return address

   // L0-L7, I0-I7   - Caller's temps (no frame pushed yet)

   // F0-F7          - more outgoing args

   // Gargs is the incoming argument base, and also an outgoing argument.

   __ sub(Gargs, BytesPerWord, Gargs);

   // ON ENTRY TO THE CODE WE ARE MAKING, WE HAVE AN INTERPRETED FRAME

   // WITH O7 HOLDING A VALID RETURN PC

   //

   // |              |

   // :  java stack  :

   // |              |

   // +--------------+ <--- start of outgoing args

   // |   receiver   |   |

   // : rest of args :   |---size is java-arg-words

   // |              |   |

   // +--------------+ <--- O4_args (misaligned) and Lesp if prior is not C2I

   // |              |   |

   // :    unused    :   |---Space for max Java stack, plus stack alignment

   // |              |   |

   // +--------------+ <--- SP + 16*wordsize

   // |              |

   // :    window    :

   // |              |

   // +--------------+ <--- SP

   // WE REPACK THE STACK.  We use the common calling convention layout as

   // discovered by calling SharedRuntime::calling_convention.  We assume it

   // causes an arbitrary shuffle of memory, which may require some register

   // temps to do the shuffle.  We hope for (and optimize for) the case where

   // temps are not needed.  We may have to resize the stack slightly, in case

   // we need alignment padding (32-bit interpreter can pass longs & doubles

   // misaligned, but the compilers expect them aligned).

   //

   // |              |

   // :  java stack  :

   // |              |

   // +--------------+ <--- start of outgoing args

   // |  pad, align  |   |

   // +--------------+   |

   // | ints, longs, |   |

   // |    floats,   |   |---Outgoing stack args.

   // :    doubles   :   |   First few args in registers.

   // |              |   |

   // +--------------+ <--- SP' + 16*wordsize

   // |              |

   // :    window    :

   // |              |

   // +--------------+ <--- SP'

   // ON EXIT FROM THE CODE WE ARE MAKING, WE STILL HAVE AN INTERPRETED FRAME

   // WITH O7 HOLDING A VALID RETURN PC - ITS JUST THAT THE ARGS ARE NOW SETUP

   // FOR COMPILED CODE AND THE FRAME SLIGHTLY GROWN.

   // Cut-out for having no stack args.  Since up to 6 args are passed

   // in registers, we will commonly have no stack args.

   if (comp_args_on_stack > 0) {

     // Convert VMReg stack slots to words.

     int comp_words_on_stack = round_to(comp_args_on_stack*VMRegImpl::stack_slot_size, wordSize)>>LogBytesPerWord;

     // Round up to miminum stack alignment, in wordSize

     comp_words_on_stack = round_to(comp_words_on_stack, 2);

     // Now compute the distance from Lesp to SP.  This calculation does not

     // include the space for total_args_passed because Lesp has not yet popped

     // the arguments.

     __ sub(SP, (comp_words_on_stack)*wordSize, SP);

   }

   // Now generate the shuffle code.  Pick up all register args and move the

   // rest through G1_scratch.

   for (int i = 0; i < total_args_passed; i++) {

     if (sig_bt[i] == T_VOID) {

       // Longs and doubles are passed in native word order, but misaligned

       // in the 32-bit build.

       assert(i > 0 && (sig_bt[i-1] == T_LONG || sig_bt[i-1] == T_DOUBLE), "missing half");

       continue;

     }

     // Pick up 0, 1 or 2 words from Lesp+offset.  Assume mis-aligned in the

     // 32-bit build and aligned in the 64-bit build.  Look for the obvious

     // ldx/lddf optimizations.

     // Load in argument order going down.

     const int ld_off = (total_args_passed-i)*Interpreter::stackElementSize;

     set_Rdisp(G1_scratch);

     VMReg r_1 = regs[i].first();

     VMReg r_2 = regs[i].second();

     if (!r_1->is_valid()) {

       assert(!r_2->is_valid(), "");

       continue;

     }

     if (r_1->is_stack()) {        // Pretend stack targets are loaded into F8/F9

       r_1 = F8->as_VMReg();        // as part of the load/store shuffle

       if (r_2->is_valid()) r_2 = r_1->next();

     }

     if (r_1->is_Register()) {  // Register argument

       Register r = r_1->as_Register()->after_restore();

       if (!r_2->is_valid()) {

         __ ld(Gargs, arg_slot(ld_off), r);

       } else {

 #ifdef _LP64

         // In V9, longs are given 2 64-bit slots in the interpreter, but the

         // data is passed in only 1 slot.

         RegisterOrConstant slot = (sig_bt[i] == T_LONG) ?

               next_arg_slot(ld_off) : arg_slot(ld_off);

         __ ldx(Gargs, slot, r);

 #else

         fatal("longs should be on stack");

 #endif

       }

     } else {

       assert(r_1->is_FloatRegister(), "");

       if (!r_2->is_valid()) {

         __ ldf(FloatRegisterImpl::S, Gargs,      arg_slot(ld_off), r_1->as_FloatRegister());

       } else {

 #ifdef _LP64

         // In V9, doubles are given 2 64-bit slots in the interpreter, but the

         // data is passed in only 1 slot.  This code also handles longs that

         // are passed on the stack, but need a stack-to-stack move through a

         // spare float register.

         RegisterOrConstant slot = (sig_bt[i] == T_LONG || sig_bt[i] == T_DOUBLE) ?

               next_arg_slot(ld_off) : arg_slot(ld_off);

         __ ldf(FloatRegisterImpl::D, Gargs,                  slot, r_1->as_FloatRegister());

 #else

         // Need to marshal 64-bit value from misaligned Lesp loads

         __ ldf(FloatRegisterImpl::S, Gargs, next_arg_slot(ld_off), r_1->as_FloatRegister());

         __ ldf(FloatRegisterImpl::S, Gargs,      arg_slot(ld_off), r_2->as_FloatRegister());

 #endif

       }

     }

     // Was the argument really intended to be on the stack, but was loaded

     // into F8/F9?

     if (regs[i].first()->is_stack()) {

       assert(r_1->as_FloatRegister() == F8, "fix this code");

       // Convert stack slot to an SP offset

       int st_off = reg2offset(regs[i].first()) + STACK_BIAS;

       // Store down the shuffled stack word.  Target address _is_ aligned.

       RegisterOrConstant slot = __ ensure_simm13_or_reg(st_off, Rdisp);

       if (!r_2->is_valid()) __ stf(FloatRegisterImpl::S, r_1->as_FloatRegister(), SP, slot);

       else                  __ stf(FloatRegisterImpl::D, r_1->as_FloatRegister(), SP, slot);

     }

   }

   // Jump to the compiled code just as if compiled code was doing it.

   __ ld_ptr(G5_method, in_bytes(Method::from_compiled_offset()), G3);

   // 6243940 We might end up in handle_wrong_method if

   // the callee is deoptimized as we race thru here. If that

   // happens we don't want to take a safepoint because the

   // caller frame will look interpreted and arguments are now

   // "compiled" so it is much better to make this transition

   // invisible to the stack walking code. Unfortunately if

   // we try and find the callee by normal means a safepoint

   // is possible. So we stash the desired callee in the thread

   // and the vm will find there should this case occur.

   Address callee_target_addr(G2_thread, JavaThread::callee_target_offset());

   __ st_ptr(G5_method, callee_target_addr);

   if (StressNonEntrant) {

     // Open a big window for deopt failure

     __ save_frame(0);

     __ mov(G0, L0);

     Label loop;

     __ bind(loop);

     __ sub(L0, 1, L0);

     __ br_null_short(L0, Assembler::pt, loop);

     __ restore();

   }

   __ jmpl(G3, 0, G0);

   __ delayed()->nop();

 }

 // ---------------------------------------------------------------

 AdapterHandlerEntry* SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm,

                                                             int total_args_passed,

                                                             // VMReg max_arg,

                                                             int comp_args_on_stack, // VMRegStackSlots

                                                             const BasicType *sig_bt,

                                                             const VMRegPair *regs,

                                                             AdapterFingerPrint* fingerprint) {

   address i2c_entry = __ pc();

   AdapterGenerator agen(masm);

   agen.gen_i2c_adapter(total_args_passed, comp_args_on_stack, sig_bt, regs);

   // -------------------------------------------------------------------------

   // Generate a C2I adapter.  On entry we know G5 holds the Method*.  The

   // args start out packed in the compiled layout.  They need to be unpacked

   // into the interpreter layout.  This will almost always require some stack

   // space.  We grow the current (compiled) stack, then repack the args.  We

   // finally end in a jump to the generic interpreter entry point.  On exit

   // from the interpreter, the interpreter will restore our SP (lest the

   // compiled code, which relys solely on SP and not FP, get sick).

   address c2i_unverified_entry = __ pc();

   Label L_skip_fixup;

   {

     Register R_temp = G1;  // another scratch register

     AddressLiteral ic_miss(SharedRuntime::get_ic_miss_stub());

     __ verify_oop(O0);

     __ load_klass(O0, G3_scratch);

     __ ld_ptr(G5_method, CompiledICHolder::holder_klass_offset(), R_temp);

     __ cmp(G3_scratch, R_temp);

     Label ok, ok2;

     __ brx(Assembler::equal, false, Assembler::pt, ok);

     __ delayed()->ld_ptr(G5_method, CompiledICHolder::holder_method_offset(), G5_method);

     __ jump_to(ic_miss, G3_scratch);

     __ delayed()->nop();

     __ bind(ok);

     // Method might have been compiled since the call site was patched to

     // interpreted if that is the case treat it as a miss so we can get

     // the call site corrected.

     __ ld_ptr(G5_method, in_bytes(Method::code_offset()), G3_scratch);

     __ bind(ok2);

     __ br_null(G3_scratch, false, Assembler::pt, L_skip_fixup);

     __ delayed()->nop();

     __ jump_to(ic_miss, G3_scratch);

     __ delayed()->nop();

   }

   address c2i_entry = __ pc();

   agen.gen_c2i_adapter(total_args_passed, comp_args_on_stack, sig_bt, regs, L_skip_fixup);

   __ flush();

   return AdapterHandlerLibrary::new_entry(fingerprint, i2c_entry, c2i_entry, c2i_unverified_entry);

 }

 // Helper function for native calling conventions

 static VMReg int_stk_helper( int i ) {

   // Bias any stack based VMReg we get by ignoring the window area

   // but not the register parameter save area.

   //

   // This is strange for the following reasons. We'd normally expect

   // the calling convention to return an VMReg for a stack slot

   // completely ignoring any abi reserved area. C2 thinks of that

   // abi area as only out_preserve_stack_slots. This does not include

   // the area allocated by the C abi to store down integer arguments

   // because the java calling convention does not use it. So

   // since c2 assumes that there are only out_preserve_stack_slots

   // to bias the optoregs (which impacts VMRegs) when actually referencing any actual stack

   // location the c calling convention must add in this bias amount

   // to make up for the fact that the out_preserve_stack_slots is

   // insufficient for C calls. What a mess. I sure hope those 6

   // stack words were worth it on every java call!

   // Another way of cleaning this up would be for out_preserve_stack_slots

   // to take a parameter to say whether it was C or java calling conventions.

   // Then things might look a little better (but not much).

   int mem_parm_offset = i - SPARC_ARGS_IN_REGS_NUM;

   if( mem_parm_offset < 0 ) {

     return as_oRegister(i)->as_VMReg();

   } else {

     int actual_offset = (mem_parm_offset + frame::memory_parameter_word_sp_offset) * VMRegImpl::slots_per_word;

     // Now return a biased offset that will be correct when out_preserve_slots is added back in

     return VMRegImpl::stack2reg(actual_offset - SharedRuntime::out_preserve_stack_slots());

   }

 }

 int SharedRuntime::c_calling_convention(const BasicType *sig_bt,

                                          VMRegPair *regs,

                                          int total_args_passed) {

     // Return the number of VMReg stack_slots needed for the args.

     // This value does not include an abi space (like register window

     // save area).

     // The native convention is V8 if !LP64

     // The LP64 convention is the V9 convention which is slightly more sane.

     // We return the amount of VMReg stack slots we need to reserve for all

     // the arguments NOT counting out_preserve_stack_slots. Since we always

     // have space for storing at least 6 registers to memory we start with that.

     // See int_stk_helper for a further discussion.

     int max_stack_slots = (frame::varargs_offset * VMRegImpl::slots_per_word) - SharedRuntime::out_preserve_stack_slots();

 #ifdef _LP64

     // V9 convention: All things "as-if" on double-wide stack slots.

     // Hoist any int/ptr/long's in the first 6 to int regs.

     // Hoist any flt/dbl's in the first 16 dbl regs.

     int j = 0;                  // Count of actual args, not HALVES

     for( int i=0; i<total_args_passed; i++, j++ ) {

       switch( sig_bt[i] ) {

       case T_BOOLEAN:

       case T_BYTE:

       case T_CHAR:

       case T_INT:

       case T_SHORT:

         regs[i].set1( int_stk_helper( j ) ); break;

       case T_LONG:

         assert( sig_bt[i+1] == T_VOID, "expecting half" );

       case T_ADDRESS: // raw pointers, like current thread, for VM calls

       case T_ARRAY:

       case T_OBJECT:

       case T_METADATA:

         regs[i].set2( int_stk_helper( j ) );

         break;

       case T_FLOAT:

         if ( j < 16 ) {

           // V9ism: floats go in ODD registers

           regs[i].set1(as_FloatRegister(1 + (j<<1))->as_VMReg());

         } else {

           // V9ism: floats go in ODD stack slot

           regs[i].set1(VMRegImpl::stack2reg(1 + (j<<1)));

         }

         break;

       case T_DOUBLE:

         assert( sig_bt[i+1] == T_VOID, "expecting half" );

         if ( j < 16 ) {

           // V9ism: doubles go in EVEN/ODD regs

           regs[i].set2(as_FloatRegister(j<<1)->as_VMReg());

         } else {

           // V9ism: doubles go in EVEN/ODD stack slots

           regs[i].set2(VMRegImpl::stack2reg(j<<1));

         }

         break;

       case T_VOID:  regs[i].set_bad(); j--; break; // Do not count HALVES

       default:

         ShouldNotReachHere();

       }

       if (regs[i].first()->is_stack()) {

         int off =  regs[i].first()->reg2stack();

         if (off > max_stack_slots) max_stack_slots = off;

       }

       if (regs[i].second()->is_stack()) {

         int off =  regs[i].second()->reg2stack();

         if (off > max_stack_slots) max_stack_slots = off;

       }

     }

 #else // _LP64

     // V8 convention: first 6 things in O-regs, rest on stack.

     // Alignment is willy-nilly.

     for( int i=0; i<total_args_passed; i++ ) {

       switch( sig_bt[i] ) {

       case T_ADDRESS: // raw pointers, like current thread, for VM calls

       case T_ARRAY:

       case T_BOOLEAN:

       case T_BYTE:

       case T_CHAR:

       case T_FLOAT:

       case T_INT:

       case T_OBJECT:

       case T_METADATA:

       case T_SHORT:

         regs[i].set1( int_stk_helper( i ) );

         break;

       case T_DOUBLE:

       case T_LONG:

         assert( sig_bt[i+1] == T_VOID, "expecting half" );

         regs[i].set_pair( int_stk_helper( i+1 ), int_stk_helper( i ) );

         break;

       case T_VOID: regs[i].set_bad(); break;

       default:

         ShouldNotReachHere();

       }

       if (regs[i].first()->is_stack()) {

         int off =  regs[i].first()->reg2stack();

         if (off > max_stack_slots) max_stack_slots = off;

       }

       if (regs[i].second()->is_stack()) {

         int off =  regs[i].second()->reg2stack();

         if (off > max_stack_slots) max_stack_slots = off;

       }

     }

 #endif // _LP64

   return round_to(max_stack_slots + 1, 2);

 }

 // ---------------------------------------------------------------------------

 void SharedRuntime::save_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {

   switch (ret_type) {

   case T_FLOAT:

     __ stf(FloatRegisterImpl::S, F0, SP, frame_slots*VMRegImpl::stack_slot_size - 4+STACK_BIAS);

     break;

   case T_DOUBLE:

     __ stf(FloatRegisterImpl::D, F0, SP, frame_slots*VMRegImpl::stack_slot_size - 8+STACK_BIAS);

     break;

   }

 }

 void SharedRuntime::restore_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {

   switch (ret_type) {

   case T_FLOAT:

     __ ldf(FloatRegisterImpl::S, SP, frame_slots*VMRegImpl::stack_slot_size - 4+STACK_BIAS, F0);

     break;

   case T_DOUBLE:

     __ ldf(FloatRegisterImpl::D, SP, frame_slots*VMRegImpl::stack_slot_size - 8+STACK_BIAS, F0);

     break;

   }

 }

 // Check and forward and pending exception.  Thread is stored in

 // L7_thread_cache and possibly NOT in G2_thread.  Since this is a native call, there

 // is no exception handler.  We merely pop this frame off and throw the

 // exception in the caller's frame.

 static void check_forward_pending_exception(MacroAssembler *masm, Register Rex_oop) {

   Label L;

   __ br_null(Rex_oop, false, Assembler::pt, L);

   __ delayed()->mov(L7_thread_cache, G2_thread); // restore in case we have exception

   // Since this is a native call, we *know* the proper exception handler

   // without calling into the VM: it's the empty function.  Just pop this

   // frame and then jump to forward_exception_entry; O7 will contain the

   // native caller's return PC.

  AddressLiteral exception_entry(StubRoutines::forward_exception_entry());

   __ jump_to(exception_entry, G3_scratch);

   __ delayed()->restore();      // Pop this frame off.

   __ bind(L);

 }

 // A simple move of integer like type

 static void simple_move32(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {

   if (src.first()->is_stack()) {

     if (dst.first()->is_stack()) {

       // stack to stack

       __ ld(FP, reg2offset(src.first()) + STACK_BIAS, L5);

       __ st(L5, SP, reg2offset(dst.first()) + STACK_BIAS);

     } else {

       // stack to reg

       __ ld(FP, reg2offset(src.first()) + STACK_BIAS, dst.first()->as_Register());

     }

   } else if (dst.first()->is_stack()) {

     // reg to stack

     __ st(src.first()->as_Register(), SP, reg2offset(dst.first()) + STACK_BIAS);

   } else {

     __ mov(src.first()->as_Register(), dst.first()->as_Register());

   }

 }

 // On 64 bit we will store integer like items to the stack as

 // 64 bits items (sparc abi) even though java would only store

 // 32bits for a parameter. On 32bit it will simply be 32 bits

 // So this routine will do 32->32 on 32bit and 32->64 on 64bit

 static void move32_64(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {

   if (src.first()->is_stack()) {

     if (dst.first()->is_stack()) {

       // stack to stack

       __ ld(FP, reg2offset(src.first()) + STACK_BIAS, L5);

       __ st_ptr(L5, SP, reg2offset(dst.first()) + STACK_BIAS);

     } else {

       // stack to reg

       __ ld(FP, reg2offset(src.first()) + STACK_BIAS, dst.first()->as_Register());

     }

   } else if (dst.first()->is_stack()) {

     // reg to stack

     __ st_ptr(src.first()->as_Register(), SP, reg2offset(dst.first()) + STACK_BIAS);

   } else {

     __ mov(src.first()->as_Register(), dst.first()->as_Register());

   }

 }

 static void move_ptr(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {

   if (src.first()->is_stack()) {

     if (dst.first()->is_stack()) {

       // stack to stack

       __ ld_ptr(FP, reg2offset(src.first()) + STACK_BIAS, L5);

       __ st_ptr(L5, SP, reg2offset(dst.first()) + STACK_BIAS);

     } else {

       // stack to reg

       __ ld_ptr(FP, reg2offset(src.first()) + STACK_BIAS, dst.first()->as_Register());

     }

   } else if (dst.first()->is_stack()) {

     // reg to stack

     __ st_ptr(src.first()->as_Register(), SP, reg2offset(dst.first()) + STACK_BIAS);

   } else {

     __ mov(src.first()->as_Register(), dst.first()->as_Register());

   }

 }

 // An oop arg. Must pass a handle not the oop itself

 static void object_move(MacroAssembler* masm,

                         OopMap* map,

                         int oop_handle_offset,

                         int framesize_in_slots,

                         VMRegPair src,

                         VMRegPair dst,

                         bool is_receiver,

                         int* receiver_offset) {

   // must pass a handle. First figure out the location we use as a handle

   if (src.first()->is_stack()) {

     // Oop is already on the stack

     Register rHandle = dst.first()->is_stack() ? L5 : dst.first()->as_Register();

     __ add(FP, reg2offset(src.first()) + STACK_BIAS, rHandle);

     __ ld_ptr(rHandle, 0, L4);

 #ifdef _LP64

     __ movr( Assembler::rc_z, L4, G0, rHandle );

 #else

     __ tst( L4 );

     __ movcc( Assembler::zero, false, Assembler::icc, G0, rHandle );

 #endif

     if (dst.first()->is_stack()) {

       __ st_ptr(rHandle, SP, reg2offset(dst.first()) + STACK_BIAS);

     }

     int offset_in_older_frame = src.first()->reg2stack() + SharedRuntime::out_preserve_stack_slots();

     if (is_receiver) {

       *receiver_offset = (offset_in_older_frame + framesize_in_slots) * VMRegImpl::stack_slot_size;

     }

     map->set_oop(VMRegImpl::stack2reg(offset_in_older_frame + framesize_in_slots));

   } else {

     // Oop is in an input register pass we must flush it to the stack

     const Register rOop = src.first()->as_Register();

     const Register rHandle = L5;

     int oop_slot = rOop->input_number() * VMRegImpl::slots_per_word + oop_handle_offset;

     int offset = oop_slot*VMRegImpl::stack_slot_size;

     Label skip;

     __ st_ptr(rOop, SP, offset + STACK_BIAS);

     if (is_receiver) {

       *receiver_offset = oop_slot * VMRegImpl::stack_slot_size;

     }

     map->set_oop(VMRegImpl::stack2reg(oop_slot));

     __ add(SP, offset + STACK_BIAS, rHandle);

 #ifdef _LP64

     __ movr( Assembler::rc_z, rOop, G0, rHandle );

 #else

     __ tst( rOop );

     __ movcc( Assembler::zero, false, Assembler::icc, G0, rHandle );

 #endif

     if (dst.first()->is_stack()) {

       __ st_ptr(rHandle, SP, reg2offset(dst.first()) + STACK_BIAS);

     } else {

       __ mov(rHandle, dst.first()->as_Register());

     }

   }

 }

 // A float arg may have to do float reg int reg conversion

 static void float_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {

   assert(!src.second()->is_valid() && !dst.second()->is_valid(), "bad float_move");

   if (src.first()->is_stack()) {

     if (dst.first()->is_stack()) {

       // stack to stack the easiest of the bunch

       __ ld(FP, reg2offset(src.first()) + STACK_BIAS, L5);

       __ st(L5, SP, reg2offset(dst.first()) + STACK_BIAS);

     } else {

       // stack to reg

       if (dst.first()->is_Register()) {

         __ ld(FP, reg2offset(src.first()) + STACK_BIAS, dst.first()->as_Register());

       } else {

         __ ldf(FloatRegisterImpl::S, FP, reg2offset(src.first()) + STACK_BIAS, dst.first()->as_FloatRegister());

       }

     }

   } else if (dst.first()->is_stack()) {

     // reg to stack

     if (src.first()->is_Register()) {

       __ st(src.first()->as_Register(), SP, reg2offset(dst.first()) + STACK_BIAS);

     } else {

       __ stf(FloatRegisterImpl::S, src.first()->as_FloatRegister(), SP, reg2offset(dst.first()) + STACK_BIAS);

     }

   } else {

     // reg to reg

     if (src.first()->is_Register()) {

       if (dst.first()->is_Register()) {

         // gpr -> gpr

         __ mov(src.first()->as_Register(), dst.first()->as_Register());

       } else {

         // gpr -> fpr

         __ st(src.first()->as_Register(), FP, -4 + STACK_BIAS);

         __ ldf(FloatRegisterImpl::S, FP, -4 + STACK_BIAS, dst.first()->as_FloatRegister());

       }

     } else if (dst.first()->is_Register()) {

       // fpr -> gpr

       __ stf(FloatRegisterImpl::S, src.first()->as_FloatRegister(), FP, -4 + STACK_BIAS);

       __ ld(FP, -4 + STACK_BIAS, dst.first()->as_Register());

     } else {

       // fpr -> fpr

       // In theory these overlap but the ordering is such that this is likely a nop

       if ( src.first() != dst.first()) {

         __ fmov(FloatRegisterImpl::S, src.first()->as_FloatRegister(), dst.first()->as_FloatRegister());

       }

     }

   }

 }

 static void split_long_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {

   VMRegPair src_lo(src.first());

   VMRegPair src_hi(src.second());

   VMRegPair dst_lo(dst.first());

   VMRegPair dst_hi(dst.second());

   simple_move32(masm, src_lo, dst_lo);

   simple_move32(masm, src_hi, dst_hi);

 }

 // A long move

 static void long_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {

   // Do the simple ones here else do two int moves

   if (src.is_single_phys_reg() ) {

     if (dst.is_single_phys_reg()) {

       __ mov(src.first()->as_Register(), dst.first()->as_Register());

     } else {

       // split src into two separate registers

       // Remember hi means hi address or lsw on sparc

       // Move msw to lsw

       if (dst.second()->is_reg()) {

         // MSW -> MSW

         __ srax(src.first()->as_Register(), 32, dst.first()->as_Register());

         // Now LSW -> LSW

         // this will only move lo -> lo and ignore hi

         VMRegPair split(dst.second());

         simple_move32(masm, src, split);

       } else {

         VMRegPair split(src.first(), L4->as_VMReg());

         // MSW -> MSW (lo ie. first word)

         __ srax(src.first()->as_Register(), 32, L4);

         split_long_move(masm, split, dst);

       }

     }

   } else if (dst.is_single_phys_reg()) {

     if (src.is_adjacent_aligned_on_stack(2)) {

       __ ldx(FP, reg2offset(src.first()) + STACK_BIAS, dst.first()->as_Register());

     } else {

       // dst is a single reg.

       // Remember lo is low address not msb for stack slots

       // and lo is the "real" register for registers

       // src is

       VMRegPair split;

       if (src.first()->is_reg()) {

         // src.lo (msw) is a reg, src.hi is stk/reg

         // we will move: src.hi (LSW) -> dst.lo, src.lo (MSW) -> src.lo [the MSW is in the LSW of the reg]

         split.set_pair(dst.first(), src.first());

       } else {

         // msw is stack move to L5

         // lsw is stack move to dst.lo (real reg)

         // we will move: src.hi (LSW) -> dst.lo, src.lo (MSW) -> L5

         split.set_pair(dst.first(), L5->as_VMReg());

       }

       // src.lo -> src.lo/L5, src.hi -> dst.lo (the real reg)

       // msw   -> src.lo/L5,  lsw -> dst.lo

       split_long_move(masm, src, split);

       // So dst now has the low order correct position the

       // msw half

       __ sllx(split.first()->as_Register(), 32, L5);

       const Register d = dst.first()->as_Register();

       __ or3(L5, d, d);

     }

   } else {

     // For LP64 we can probably do better.

     split_long_move(masm, src, dst);

   }

 }

 // A double move

 static void double_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {

   // The painful thing here is that like long_move a VMRegPair might be

   // 1: a single physical register

   // 2: two physical registers (v8)

   // 3: a physical reg [lo] and a stack slot [hi] (v8)

   // 4: two stack slots

   // Since src is always a java calling convention we know that the src pair

   // is always either all registers or all stack (and aligned?)

   // in a register [lo] and a stack slot [hi]

   if (src.first()->is_stack()) {

     if (dst.first()->is_stack()) {

       // stack to stack the easiest of the bunch

       // ought to be a way to do this where if alignment is ok we use ldd/std when possible

       __ ld(FP, reg2offset(src.first()) + STACK_BIAS, L5);

       __ ld(FP, reg2offset(src.second()) + STACK_BIAS, L4);

       __ st(L5, SP, reg2offset(dst.first()) + STACK_BIAS);

       __ st(L4, SP, reg2offset(dst.second()) + STACK_BIAS);

     } else {

       // stack to reg

       if (dst.second()->is_stack()) {

         // stack -> reg, stack -> stack

         __ ld(FP, reg2offset(src.second()) + STACK_BIAS, L4);

         if (dst.first()->is_Register()) {

           __ ld(FP, reg2offset(src.first()) + STACK_BIAS, dst.first()->as_Register());

         } else {

           __ ldf(FloatRegisterImpl::S, FP, reg2offset(src.first()) + STACK_BIAS, dst.first()->as_FloatRegister());

         }

         // This was missing. (very rare case)

         __ st(L4, SP, reg2offset(dst.second()) + STACK_BIAS);

       } else {

         // stack -> reg

         // Eventually optimize for alignment QQQ

         if (dst.first()->is_Register()) {

           __ ld(FP, reg2offset(src.first()) + STACK_BIAS, dst.first()->as_Register());

           __ ld(FP, reg2offset(src.second()) + STACK_BIAS, dst.second()->as_Register());

         } else {

           __ ldf(FloatRegisterImpl::S, FP, reg2offset(src.first()) + STACK_BIAS, dst.first()->as_FloatRegister());

           __ ldf(FloatRegisterImpl::S, FP, reg2offset(src.second()) + STACK_BIAS, dst.second()->as_FloatRegister());

         }

       }

     }

   } else if (dst.first()->is_stack()) {

     // reg to stack

     if (src.first()->is_Register()) {

       // Eventually optimize for alignment QQQ

       __ st(src.first()->as_Register(), SP, reg2offset(dst.first()) + STACK_BIAS);

       if (src.second()->is_stack()) {

         __ ld(FP, reg2offset(src.second()) + STACK_BIAS, L4);

         __ st(L4, SP, reg2offset(dst.second()) + STACK_BIAS);

       } else {

         __ st(src.second()->as_Register(), SP, reg2offset(dst.second()) + STACK_BIAS);

       }

     } else {

       // fpr to stack

       if (src.second()->is_stack()) {

         ShouldNotReachHere();

       } else {

         // Is the stack aligned?

         if (reg2offset(dst.first()) & 0x7) {

           // No do as pairs

           __ stf(FloatRegisterImpl::S, src.first()->as_FloatRegister(), SP, reg2offset(dst.first()) + STACK_BIAS);

           __ stf(FloatRegisterImpl::S, src.second()->as_FloatRegister(), SP, reg2offset(dst.second()) + STACK_BIAS);

         } else {

           __ stf(FloatRegisterImpl::D, src.first()->as_FloatRegister(), SP, reg2offset(dst.first()) + STACK_BIAS);

         }

       }

     }

   } else {

     // reg to reg

     if (src.first()->is_Register()) {

       if (dst.first()->is_Register()) {

         // gpr -> gpr

         __ mov(src.first()->as_Register(), dst.first()->as_Register());

         __ mov(src.second()->as_Register(), dst.second()->as_Register());

       } else {

         // gpr -> fpr

         // ought to be able to do a single store

         __ stx(src.first()->as_Register(), FP, -8 + STACK_BIAS);

         __ stx(src.second()->as_Register(), FP, -4 + STACK_BIAS);

         // ought to be able to do a single load

         __ ldf(FloatRegisterImpl::S, FP, -8 + STACK_BIAS, dst.first()->as_FloatRegister());

         __ ldf(FloatRegisterImpl::S, FP, -4 + STACK_BIAS, dst.second()->as_FloatRegister());

       }

     } else if (dst.first()->is_Register()) {

       // fpr -> gpr

       // ought to be able to do a single store

       __ stf(FloatRegisterImpl::D, src.first()->as_FloatRegister(), FP, -8 + STACK_BIAS);

       // ought to be able to do a single load

       // REMEMBER first() is low address not LSB

       __ ld(FP, -8 + STACK_BIAS, dst.first()->as_Register());

       if (dst.second()->is_Register()) {

         __ ld(FP, -4 + STACK_BIAS, dst.second()->as_Register());

       } else {

         __ ld(FP, -4 + STACK_BIAS, L4);

         __ st(L4, SP, reg2offset(dst.second()) + STACK_BIAS);

       }

     } else {

       // fpr -> fpr

       // In theory these overlap but the ordering is such that this is likely a nop

       if ( src.first() != dst.first()) {

         __ fmov(FloatRegisterImpl::D, src.first()->as_FloatRegister(), dst.first()->as_FloatRegister());

       }

     }

   }

 }

 // Creates an inner frame if one hasn't already been created, and

 // saves a copy of the thread in L7_thread_cache

 static void create_inner_frame(MacroAssembler* masm, bool* already_created) {

   if (!*already_created) {

     __ save_frame(0);

     // Save thread in L7 (INNER FRAME); it crosses a bunch of VM calls below

     // Don't use save_thread because it smashes G2 and we merely want to save a

     // copy

     __ mov(G2_thread, L7_thread_cache);

     *already_created = true;

   }

 }

 static void save_or_restore_arguments(MacroAssembler* masm,

                                       const int stack_slots,

                                       const int total_in_args,

                                       const int arg_save_area,

                                       OopMap* map,

                                       VMRegPair* in_regs,

                                       BasicType* in_sig_bt) {

   // if map is non-NULL then the code should store the values,

   // otherwise it should load them.

   if (map != NULL) {

     // Fill in the map

     for (int i = 0; i < total_in_args; i++) {

       if (in_sig_bt[i] == T_ARRAY) {

         if (in_regs[i].first()->is_stack()) {

           int offset_in_older_frame = in_regs[i].first()->reg2stack() + SharedRuntime::out_preserve_stack_slots();

           map->set_oop(VMRegImpl::stack2reg(offset_in_older_frame + stack_slots));

         } else if (in_regs[i].first()->is_Register()) {

           map->set_oop(in_regs[i].first());

         } else {

           ShouldNotReachHere();

         }

       }

     }

   }

   // Save or restore double word values

   int handle_index = 0;

   for (int i = 0; i < total_in_args; i++) {

     int slot = handle_index + arg_save_area;

     int offset = slot * VMRegImpl::stack_slot_size;

     if (in_sig_bt[i] == T_LONG && in_regs[i].first()->is_Register()) {

       const Register reg = in_regs[i].first()->as_Register();

       if (reg->is_global()) {

         handle_index += 2;

         assert(handle_index <= stack_slots, "overflow");

         if (map != NULL) {

           __ stx(reg, SP, offset + STACK_BIAS);

         } else {

           __ ldx(SP, offset + STACK_BIAS, reg);

         }

       }

     } else if (in_sig_bt[i] == T_DOUBLE && in_regs[i].first()->is_FloatRegister()) {

       handle_index += 2;

       assert(handle_index <= stack_slots, "overflow");

       if (map != NULL) {

         __ stf(FloatRegisterImpl::D, in_regs[i].first()->as_FloatRegister(), SP, offset + STACK_BIAS);

       } else {

         __ ldf(FloatRegisterImpl::D, SP, offset + STACK_BIAS, in_regs[i].first()->as_FloatRegister());

       }

     }

   }

   // Save floats

   for (int i = 0; i < total_in_args; i++) {

     int slot = handle_index + arg_save_area;

     int offset = slot * VMRegImpl::stack_slot_size;

     if (in_sig_bt[i] == T_FLOAT && in_regs[i].first()->is_FloatRegister()) {

       handle_index++;

       assert(handle_index <= stack_slots, "overflow");

       if (map != NULL) {

         __ stf(FloatRegisterImpl::S, in_regs[i].first()->as_FloatRegister(), SP, offset + STACK_BIAS);

       } else {

         __ ldf(FloatRegisterImpl::S, SP, offset + STACK_BIAS, in_regs[i].first()->as_FloatRegister());

       }

     }

   }

 }

 // Check GC_locker::needs_gc and enter the runtime if it's true.  This

 // keeps a new JNI critical region from starting until a GC has been

 // forced.  Save down any oops in registers and describe them in an

 // OopMap.

 static void check_needs_gc_for_critical_native(MacroAssembler* masm,

                                                const int stack_slots,

                                                const int total_in_args,

                                                const int arg_save_area,

                                                OopMapSet* oop_maps,

                                                VMRegPair* in_regs,

                                                BasicType* in_sig_bt) {

   __ block_comment("check GC_locker::needs_gc");

   Label cont;

   AddressLiteral sync_state(GC_locker::needs_gc_address());

   __ load_bool_contents(sync_state, G3_scratch);

   __ cmp_zero_and_br(Assembler::equal, G3_scratch, cont);

   __ delayed()->nop();

   // Save down any values that are live in registers and call into the

   // runtime to halt for a GC

   OopMap* map = new OopMap(stack_slots * 2, 0 /* arg_slots*/);

   save_or_restore_arguments(masm, stack_slots, total_in_args,

                             arg_save_area, map, in_regs, in_sig_bt);

   __ mov(G2_thread, L7_thread_cache);

   __ set_last_Java_frame(SP, noreg);

   __ block_comment("block_for_jni_critical");

   __ call(CAST_FROM_FN_PTR(address, SharedRuntime::block_for_jni_critical), relocInfo::runtime_call_type);

   __ delayed()->mov(L7_thread_cache, O0);

   oop_maps->add_gc_map( __ offset(), map);

   __ restore_thread(L7_thread_cache); // restore G2_thread

   __ reset_last_Java_frame();

   // Reload all the register arguments

   save_or_restore_arguments(masm, stack_slots, total_in_args,

                             arg_save_area, NULL, in_regs, in_sig_bt);

   __ bind(cont);

 #ifdef ASSERT

   if (StressCriticalJNINatives) {

     // Stress register saving

     OopMap* map = new OopMap(stack_slots * 2, 0 /* arg_slots*/);

     save_or_restore_arguments(masm, stack_slots, total_in_args,

                               arg_save_area, map, in_regs, in_sig_bt);

     // Destroy argument registers

     for (int i = 0; i < total_in_args; i++) {

       if (in_regs[i].first()->is_Register()) {

         const Register reg = in_regs[i].first()->as_Register();

         if (reg->is_global()) {

           __ mov(G0, reg);

         }

       } else if (in_regs[i].first()->is_FloatRegister()) {

         __ fneg(FloatRegisterImpl::D, in_regs[i].first()->as_FloatRegister(), in_regs[i].first()->as_FloatRegister());

       }

     }

     save_or_restore_arguments(masm, stack_slots, total_in_args,

                               arg_save_area, NULL, in_regs, in_sig_bt);

   }

 #endif

 }

 // Unpack an array argument into a pointer to the body and the length

 // if the array is non-null, otherwise pass 0 for both.

 static void unpack_array_argument(MacroAssembler* masm, VMRegPair reg, BasicType in_elem_type, VMRegPair body_arg, VMRegPair length_arg) {

   // Pass the length, ptr pair

   Label is_null, done;

   if (reg.first()->is_stack()) {

     VMRegPair tmp  = reg64_to_VMRegPair(L2);

     // Load the arg up from the stack

     move_ptr(masm, reg, tmp);

     reg = tmp;

   }

   __ cmp(reg.first()->as_Register(), G0);

   __ brx(Assembler::equal, false, Assembler::pt, is_null);

   __ delayed()->add(reg.first()->as_Register(), arrayOopDesc::base_offset_in_bytes(in_elem_type), L4);

   move_ptr(masm, reg64_to_VMRegPair(L4), body_arg);

   __ ld(reg.first()->as_Register(), arrayOopDesc::length_offset_in_bytes(), L4);

   move32_64(masm, reg64_to_VMRegPair(L4), length_arg);

   __ ba_short(done);

   __ bind(is_null);

   // Pass zeros

   move_ptr(masm, reg64_to_VMRegPair(G0), body_arg);

   move32_64(masm, reg64_to_VMRegPair(G0), length_arg);

   __ bind(done);

 }

 static void verify_oop_args(MacroAssembler* masm,

                             methodHandle method,

                             const BasicType* sig_bt,

                             const VMRegPair* regs) {

   Register temp_reg = G5_method;  // not part of any compiled calling seq

   if (VerifyOops) {

     for (int i = 0; i < method->size_of_parameters(); i++) {

       if (sig_bt[i] == T_OBJECT ||

           sig_bt[i] == T_ARRAY) {

         VMReg r = regs[i].first();

         assert(r->is_valid(), "bad oop arg");

         if (r->is_stack()) {

           RegisterOrConstant ld_off = reg2offset(r) + STACK_BIAS;

           ld_off = __ ensure_simm13_or_reg(ld_off, temp_reg);

           __ ld_ptr(SP, ld_off, temp_reg);

           __ verify_oop(temp_reg);

         } else {

           __ verify_oop(r->as_Register());

         }

       }

     }

   }

 }

 static void gen_special_dispatch(MacroAssembler* masm,

                                  methodHandle method,

                                  const BasicType* sig_bt,

                                  const VMRegPair* regs) {

   verify_oop_args(masm, method, sig_bt, regs);

   vmIntrinsics::ID iid = method->intrinsic_id();

   // Now write the args into the outgoing interpreter space

   bool     has_receiver   = false;

   Register receiver_reg   = noreg;

   int      member_arg_pos = -1;

   Register member_reg     = noreg;

   int      ref_kind       = MethodHandles::signature_polymorphic_intrinsic_ref_kind(iid);

   if (ref_kind != 0) {

     member_arg_pos = method->size_of_parameters() - 1;  // trailing MemberName argument

     member_reg = G5_method;  // known to be free at this point

     has_receiver = MethodHandles::ref_kind_has_receiver(ref_kind);

   } else if (iid == vmIntrinsics::_invokeBasic) {

     has_receiver = true;

   } else {

     fatal(err_msg_res("unexpected intrinsic id %d", iid));

   }

   if (member_reg != noreg) {

     // Load the member_arg into register, if necessary.

     SharedRuntime::check_member_name_argument_is_last_argument(method, sig_bt, regs);

     VMReg r = regs[member_arg_pos].first();

     if (r->is_stack()) {

       RegisterOrConstant ld_off = reg2offset(r) + STACK_BIAS;

       ld_off = __ ensure_simm13_or_reg(ld_off, member_reg);

       __ ld_ptr(SP, ld_off, member_reg);

     } else {

       // no data motion is needed

       member_reg = r->as_Register();

     }

   }

   if (has_receiver) {

     // Make sure the receiver is loaded into a register.

     assert(method->size_of_parameters() > 0, "oob");

     assert(sig_bt[0] == T_OBJECT, "receiver argument must be an object");

     VMReg r = regs[0].first();

     assert(r->is_valid(), "bad receiver arg");

     if (r->is_stack()) {

       // Porting note:  This assumes that compiled calling conventions always

       // pass the receiver oop in a register.  If this is not true on some

       // platform, pick a temp and load the receiver from stack.

       fatal("receiver always in a register");

       receiver_reg = G3_scratch;  // known to be free at this point

       RegisterOrConstant ld_off = reg2offset(r) + STACK_BIAS;

       ld_off = __ ensure_simm13_or_reg(ld_off, member_reg);

       __ ld_ptr(SP, ld_off, receiver_reg);

     } else {

       // no data motion is needed

       receiver_reg = r->as_Register();

     }

   }

   // Figure out which address we are really jumping to:

   MethodHandles::generate_method_handle_dispatch(masm, iid,

                                                  receiver_reg, member_reg, /*for_compiler_entry:*/ true);

 }

 // ---------------------------------------------------------------------------

 // Generate a native wrapper for a given method.  The method takes arguments

 // in the Java compiled code convention, marshals them to the native

 // convention (handlizes oops, etc), transitions to native, makes the call,

 // returns to java state (possibly blocking), unhandlizes any result and

 // returns.

 //

 // Critical native functions are a shorthand for the use of

 // GetPrimtiveArrayCritical and disallow the use of any other JNI

 // functions.  The wrapper is expected to unpack the arguments before

 // passing them to the callee and perform checks before and after the

 // native call to ensure that they GC_locker

 // lock_critical/unlock_critical semantics are followed.  Some other

 // parts of JNI setup are skipped like the tear down of the JNI handle

 // block and the check for pending exceptions it's impossible for them

 // to be thrown.

 //

 // They are roughly structured like this:

 //    if (GC_locker::needs_gc())

 //      SharedRuntime::block_for_jni_critical();

 //    tranistion to thread_in_native

 //    unpack arrray arguments and call native entry point

 //    check for safepoint in progress

 //    check if any thread suspend flags are set

 //      call into JVM and possible unlock the JNI critical

 //      if a GC was suppressed while in the critical native.

 //    transition back to thread_in_Java

 //    return to caller

 //

 nmethod* SharedRuntime::generate_native_wrapper(MacroAssembler* masm,

                                                 methodHandle method,

                                                 int compile_id,

                                                 BasicType* in_sig_bt,

                                                 VMRegPair* in_regs,

                                                 BasicType ret_type) {

   if (method->is_method_handle_intrinsic()) {

     vmIntrinsics::ID iid = method->intrinsic_id();

     intptr_t start = (intptr_t)__ pc();

     int vep_offset = ((intptr_t)__ pc()) - start;

     gen_special_dispatch(masm,

                          method,

                          in_sig_bt,

                          in_regs);

     int frame_complete = ((intptr_t)__ pc()) - start;  // not complete, period

     __ flush();

     int stack_slots = SharedRuntime::out_preserve_stack_slots();  // no out slots at all, actually

     return nmethod::new_native_nmethod(method,

                                        compile_id,

                                        masm->code(),

                                        vep_offset,

                                        frame_complete,

                                        stack_slots / VMRegImpl::slots_per_word,

                                        in_ByteSize(-1),

                                        in_ByteSize(-1),

                                        (OopMapSet*)NULL);

   }

   bool is_critical_native = true;

   address native_func = method->critical_native_function();

   if (native_func == NULL) {

     native_func = method->native_function();

     is_critical_native = false;

   }

   assert(native_func != NULL, "must have function");

   // Native nmethod wrappers never take possesion of the oop arguments.

   // So the caller will gc the arguments. The only thing we need an

   // oopMap for is if the call is static

   //

   // An OopMap for lock (and class if static), and one for the VM call itself

   OopMapSet *oop_maps = new OopMapSet();

   intptr_t start = (intptr_t)__ pc();

   // First thing make an ic check to see if we should even be here

   {

     Label L;

     const Register temp_reg = G3_scratch;

     AddressLiteral ic_miss(SharedRuntime::get_ic_miss_stub());

     __ verify_oop(O0);

     __ load_klass(O0, temp_reg);

     __ cmp_and_brx_short(temp_reg, G5_inline_cache_reg, Assembler::equal, Assembler::pt, L);

     __ jump_to(ic_miss, temp_reg);

     __ delayed()->nop();

     __ align(CodeEntryAlignment);

     __ bind(L);

   }

   int vep_offset = ((intptr_t)__ pc()) - start;

 #ifdef COMPILER1

   if (InlineObjectHash && method->intrinsic_id() == vmIntrinsics::_hashCode) {

     // Object.hashCode can pull the hashCode from the header word

     // instead of doing a full VM transition once it's been computed.

     // Since hashCode is usually polymorphic at call sites we can't do

     // this optimization at the call site without a lot of work.

     Label slowCase;

     Register receiver             = O0;

     Register result               = O0;

     Register header               = G3_scratch;

     Register hash                 = G3_scratch; // overwrite header value with hash value

     Register mask                 = G1;         // to get hash field from header

     // Read the header and build a mask to get its hash field.  Give up if the object is not unlocked.

     // We depend on hash_mask being at most 32 bits and avoid the use of

     // hash_mask_in_place because it could be larger than 32 bits in a 64-bit

     // vm: see markOop.hpp.

     __ ld_ptr(receiver, oopDesc::mark_offset_in_bytes(), header);

     __ sethi(markOopDesc::hash_mask, mask);

     __ btst(markOopDesc::unlocked_value, header);

     __ br(Assembler::zero, false, Assembler::pn, slowCase);

     if (UseBiasedLocking) {

       // Check if biased and fall through to runtime if so

       __ delayed()->nop();

       __ btst(markOopDesc::biased_lock_bit_in_place, header);

       __ br(Assembler::notZero, false, Assembler::pn, slowCase);

     }

     __ delayed()->or3(mask, markOopDesc::hash_mask & 0x3ff, mask);

     // Check for a valid (non-zero) hash code and get its value.

 #ifdef _LP64

     __ srlx(header, markOopDesc::hash_shift, hash);

 #else

     __ srl(header, markOopDesc::hash_shift, hash);

 #endif

     __ andcc(hash, mask, hash);

     __ br(Assembler::equal, false, Assembler::pn, slowCase);

     __ delayed()->nop();

     // leaf return.

     __ retl();

     __ delayed()->mov(hash, result);

     __ bind(slowCase);

   }

 #endif // COMPILER1

   // We have received a description of where all the java arg are located

   // on entry to the wrapper. We need to convert these args to where

   // the jni function will expect them. To figure out where they go

   // we convert the java signature to a C signature by inserting

   // the hidden arguments as arg[0] and possibly arg[1] (static method)

   const int total_in_args = method->size_of_parameters();

   int total_c_args = total_in_args;

   int total_save_slots = 6 * VMRegImpl::slots_per_word;

   if (!is_critical_native) {

     total_c_args += 1;

     if (method->is_static()) {

       total_c_args++;

     }

   } else {

     for (int i = 0; i < total_in_args; i++) {

       if (in_sig_bt[i] == T_ARRAY) {

         // These have to be saved and restored across the safepoint

         total_c_args++;

       }

     }

   }

   BasicType* out_sig_bt = NEW_RESOURCE_ARRAY(BasicType, total_c_args);

   VMRegPair* out_regs   = NEW_RESOURCE_ARRAY(VMRegPair, total_c_args);

   BasicType* in_elem_bt = NULL;

   int argc = 0;

   if (!is_critical_native) {

     out_sig_bt[argc++] = T_ADDRESS;

     if (method->is_static()) {

       out_sig_bt[argc++] = T_OBJECT;

     }

     for (int i = 0; i < total_in_args ; i++ ) {

       out_sig_bt[argc++] = in_sig_bt[i];

     }

   } else {

     Thread* THREAD = Thread::current();

     in_elem_bt = NEW_RESOURCE_ARRAY(BasicType, total_in_args);

     SignatureStream ss(method->signature());

     for (int i = 0; i < total_in_args ; i++ ) {

       if (in_sig_bt[i] == T_ARRAY) {

         // Arrays are passed as int, elem* pair

         out_sig_bt[argc++] = T_INT;

         out_sig_bt[argc++] = T_ADDRESS;

         Symbol* atype = ss.as_symbol(CHECK_NULL);

         const char* at = atype->as_C_string();

         if (strlen(at) == 2) {

           assert(at[0] == '[', "must be");

           switch (at[1]) {

             case 'B': in_elem_bt[i]  = T_BYTE; break;

             case 'C': in_elem_bt[i]  = T_CHAR; break;

             case 'D': in_elem_bt[i]  = T_DOUBLE; break;

             case 'F': in_elem_bt[i]  = T_FLOAT; break;

             case 'I': in_elem_bt[i]  = T_INT; break;

             case 'J': in_elem_bt[i]  = T_LONG; break;

             case 'S': in_elem_bt[i]  = T_SHORT; break;

             case 'Z': in_elem_bt[i]  = T_BOOLEAN; break;

             default: ShouldNotReachHere();

           }

         }

       } else {

         out_sig_bt[argc++] = in_sig_bt[i];

         in_elem_bt[i] = T_VOID;

       }

       if (in_sig_bt[i] != T_VOID) {

         assert(in_sig_bt[i] == ss.type(), "must match");

         ss.next();

       }

     }

   }

   // Now figure out where the args must be stored and how much stack space

   // they require (neglecting out_preserve_stack_slots but space for storing

   // the 1st six register arguments). It's weird see int_stk_helper.

   //

   int out_arg_slots;

   out_arg_slots = c_calling_convention(out_sig_bt, out_regs, total_c_args);

   if (is_critical_native) {

     // Critical natives may have to call out so they need a save area

     // for register arguments.

     int double_slots = 0;

     int single_slots = 0;

     for ( int i = 0; i < total_in_args; i++) {

       if (in_regs[i].first()->is_Register()) {

         const Register reg = in_regs[i].first()->as_Register();

         switch (in_sig_bt[i]) {

           case T_ARRAY:

           case T_BOOLEAN:

           case T_BYTE:

           case T_SHORT:

           case T_CHAR:

           case T_INT:  assert(reg->is_in(), "don't need to save these"); break;

           case T_LONG: if (reg->is_global()) double_slots++; break;

           default:  ShouldNotReachHere();

         }

       } else if (in_regs[i].first()->is_FloatRegister()) {

         switch (in_sig_bt[i]) {

           case T_FLOAT:  single_slots++; break;

           case T_DOUBLE: double_slots++; break;

           default:  ShouldNotReachHere();

         }

       }

     }

     total_save_slots = double_slots * 2 + single_slots;

   }

   // Compute framesize for the wrapper.  We need to handlize all oops in

   // registers. We must create space for them here that is disjoint from

   // the windowed save area because we have no control over when we might

   // flush the window again and overwrite values that gc has since modified.

   // (The live window race)

   //

   // We always just allocate 6 word for storing down these object. This allow

   // us to simply record the base and use the Ireg number to decide which

   // slot to use. (Note that the reg number is the inbound number not the

   // outbound number).

   // We must shuffle args to match the native convention, and include var-args space.

   // Calculate the total number of stack slots we will need.

   // First count the abi requirement plus all of the outgoing args

   int stack_slots = SharedRuntime::out_preserve_stack_slots() + out_arg_slots;

   // Now the space for the inbound oop handle area

   int oop_handle_offset = round_to(stack_slots, 2);

   stack_slots += total_save_slots;

   // Now any space we need for handlizing a klass if static method

   int klass_slot_offset = 0;

   int klass_offset = -1;

   int lock_slot_offset = 0;

   bool is_static = false;

   if (method->is_static()) {

     klass_slot_offset = stack_slots;

     stack_slots += VMRegImpl::slots_per_word;

     klass_offset = klass_slot_offset * VMRegImpl::stack_slot_size;

     is_static = true;

   }

   // Plus a lock if needed

   if (method->is_synchronized()) {

     lock_slot_offset = stack_slots;

     stack_slots += VMRegImpl::slots_per_word;

   }

   // Now a place to save return value or as a temporary for any gpr -> fpr moves

   stack_slots += 2;

   // Ok The space we have allocated will look like:

   //

   //

   // FP-> |                     |

   //      |---------------------|

   //      | 2 slots for moves   |

   //      |---------------------|

   //      | lock box (if sync)  |

   //      |---------------------| <- lock_slot_offset

   //      | klass (if static)   |

   //      |---------------------| <- klass_slot_offset

   //      | oopHandle area      |

   //      |---------------------| <- oop_handle_offset

   //      | outbound memory     |

   //      | based arguments     |

   //      |                     |

   //      |---------------------|

   //      | vararg area         |

   //      |---------------------|

   //      |                     |

   // SP-> | out_preserved_slots |

   //

   //

   // Now compute actual number of stack words we need rounding to make

   // stack properly aligned.

   stack_slots = round_to(stack_slots, 2 * VMRegImpl::slots_per_word);

   int stack_size = stack_slots * VMRegImpl::stack_slot_size;

   // Generate stack overflow check before creating frame

   __ generate_stack_overflow_check(stack_size);

   // Generate a new frame for the wrapper.

   __ save(SP, -stack_size, SP);

   int frame_complete = ((intptr_t)__ pc()) - start;

   __ verify_thread();

   if (is_critical_native) {

     check_needs_gc_for_critical_native(masm, stack_slots,  total_in_args,

                                        oop_handle_offset, oop_maps, in_regs, in_sig_bt);

   }

   //

   // We immediately shuffle the arguments so that any vm call we have to

   // make from here on out (sync slow path, jvmti, etc.) we will have

   // captured the oops from our caller and have a valid oopMap for

   // them.

   // -----------------

   // The Grand Shuffle

   //

   // Natives require 1 or 2 extra arguments over the normal ones: the JNIEnv*

   // (derived from JavaThread* which is in L7_thread_cache) and, if static,

   // the class mirror instead of a receiver.  This pretty much guarantees that

   // register layout will not match.  We ignore these extra arguments during

   // the shuffle. The shuffle is described by the two calling convention

   // vectors we have in our possession. We simply walk the java vector to

   // get the source locations and the c vector to get the destinations.

   // Because we have a new window and the argument registers are completely

   // disjoint ( I0 -> O1, I1 -> O2, ...) we have nothing to worry about

   // here.

   // This is a trick. We double the stack slots so we can claim

   // the oops in the caller's frame. Since we are sure to have

   // more args than the caller doubling is enough to make

   // sure we can capture all the incoming oop args from the

   // caller.

   //

   OopMap* map = new OopMap(stack_slots * 2, 0 /* arg_slots*/);

   // Record sp-based slot for receiver on stack for non-static methods

   int receiver_offset = -1;

   // We move the arguments backward because the floating point registers

   // destination will always be to a register with a greater or equal register

   // number or the stack.

 #ifdef ASSERT

   bool reg_destroyed[RegisterImpl::number_of_registers];

   bool freg_destroyed[FloatRegisterImpl::number_of_registers];

   for ( int r = 0 ; r < RegisterImpl::number_of_registers ; r++ ) {

     reg_destroyed[r] = false;

   }

   for ( int f = 0 ; f < FloatRegisterImpl::number_of_registers ; f++ ) {

     freg_destroyed[f] = false;

   }

 #endif /* ASSERT */

   for ( int i = total_in_args - 1, c_arg = total_c_args - 1; i >= 0 ; i--, c_arg-- ) {

 #ifdef ASSERT

     if (in_regs[i].first()->is_Register()) {

       assert(!reg_destroyed[in_regs[i].first()->as_Register()->encoding()], "ack!");

     } else if (in_regs[i].first()->is_FloatRegister()) {

       assert(!freg_destroyed[in_regs[i].first()->as_FloatRegister()->encoding(FloatRegisterImpl::S)], "ack!");

     }

     if (out_regs[c_arg].first()->is_Register()) {

       reg_destroyed[out_regs[c_arg].first()->as_Register()->encoding()] = true;

     } else if (out_regs[c_arg].first()->is_FloatRegister()) {

       freg_destroyed[out_regs[c_arg].first()->as_FloatRegister()->encoding(FloatRegisterImpl::S)] = true;

     }

 #endif /* ASSERT */

     switch (in_sig_bt[i]) {

       case T_ARRAY:

         if (is_critical_native) {

           unpack_array_argument(masm, in_regs[i], in_elem_bt[i], out_regs[c_arg], out_regs[c_arg - 1]);

           c_arg--;

           break;

         }

       case T_OBJECT:

         assert(!is_critical_native, "no oop arguments");

         object_move(masm, map, oop_handle_offset, stack_slots, in_regs[i], out_regs[c_arg],

                     ((i == 0) && (!is_static)),

                     &receiver_offset);

         break;

       case T_VOID:

         break;

       case T_FLOAT:

         float_move(masm, in_regs[i], out_regs[c_arg]);

         break;

       case T_DOUBLE:

         assert( i + 1 < total_in_args &&

                 in_sig_bt[i + 1] == T_VOID &&

                 out_sig_bt[c_arg+1] == T_VOID, "bad arg list");

         double_move(masm, in_regs[i], out_regs[c_arg]);

         break;

       case T_LONG :

         long_move(masm, in_regs[i], out_regs[c_arg]);

         break;

       case T_ADDRESS: assert(false, "found T_ADDRESS in java args");

       default:

         move32_64(masm, in_regs[i], out_regs[c_arg]);

     }

   }

   // Pre-load a static method's oop into O1.  Used both by locking code and

   // the normal JNI call code.

   if (method->is_static() && !is_critical_native) {

     __ set_oop_constant(JNIHandles::make_local(Klass::cast(method->method_holder())->java_mirror()), O1);

     // Now handlize the static class mirror in O1.  It's known not-null.

     __ st_ptr(O1, SP, klass_offset + STACK_BIAS);

     map->set_oop(VMRegImpl::stack2reg(klass_slot_offset));

     __ add(SP, klass_offset + STACK_BIAS, O1);

   }

   const Register L6_handle = L6;

   if (method->is_synchronized()) {

     assert(!is_critical_native, "unhandled");

     __ mov(O1, L6_handle);

   }

   // We have all of the arguments setup at this point. We MUST NOT touch any Oregs

   // except O6/O7. So if we must call out we must push a new frame. We immediately

   // push a new frame and flush the windows.

 #ifdef _LP64

   intptr_t thepc = (intptr_t) __ pc();

   {

     address here = __ pc();

     // Call the next instruction

     __ call(here + 8, relocInfo::none);

     __ delayed()->nop();

   }

 #else

   intptr_t thepc = __ load_pc_address(O7, 0);

 #endif /* _LP64 */

   // We use the same pc/oopMap repeatedly when we call out

   oop_maps->add_gc_map(thepc - start, map);

   // O7 now has the pc loaded that we will use when we finally call to native.

   // Save thread in L7; it crosses a bunch of VM calls below

   // Don't use save_thread because it smashes G2 and we merely

   // want to save a copy

   __ mov(G2_thread, L7_thread_cache);

   // If we create an inner frame once is plenty

   // when we create it we must also save G2_thread

   bool inner_frame_created = false;

   // dtrace method entry support

   {

     SkipIfEqual skip_if(

       masm, G3_scratch, &DTraceMethodProbes, Assembler::zero);

     // create inner frame

     __ save_frame(0);

     __ mov(G2_thread, L7_thread_cache);

     __ set_metadata_constant(method(), O1);

     __ call_VM_leaf(L7_thread_cache,

          CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_entry),

          G2_thread, O1);

     __ restore();

   }

   // RedefineClasses() tracing support for obsolete method entry

   if (RC_TRACE_IN_RANGE(0x00001000, 0x00002000)) {

     // create inner frame

     __ save_frame(0);

     __ mov(G2_thread, L7_thread_cache);

     __ set_metadata_constant(method(), O1);

     __ call_VM_leaf(L7_thread_cache,

          CAST_FROM_FN_PTR(address, SharedRuntime::rc_trace_method_entry),

          G2_thread, O1);

     __ restore();

   }

   // We are in the jni frame unless saved_frame is true in which case

   // we are in one frame deeper (the "inner" frame). If we are in the

   // "inner" frames the args are in the Iregs and if the jni frame then

   // they are in the Oregs.

   // If we ever need to go to the VM (for locking, jvmti) then

   // we will always be in the "inner" frame.

   // Lock a synchronized method

   int lock_offset = -1;         // Set if locked

   if (method->is_synchronized()) {

     Register Roop = O1;

     const Register L3_box = L3;

     create_inner_frame(masm, &inner_frame_created);

     __ ld_ptr(I1, 0, O1);

     Label done;

     lock_offset = (lock_slot_offset * VMRegImpl::stack_slot_size);

     __ add(FP, lock_offset+STACK_BIAS, L3_box);

 #ifdef ASSERT

     if (UseBiasedLocking) {

       // making the box point to itself will make it clear it went unused

       // but also be obviously invalid

       __ st_ptr(L3_box, L3_box, 0);

     }

 #endif // ASSERT

     //

     // Compiler_lock_object (Roop, Rmark, Rbox, Rscratch) -- kills Rmark, Rbox, Rscratch

     //

     __ compiler_lock_object(Roop, L1,    L3_box, L2);

     __ br(Assembler::equal, false, Assembler::pt, done);

     __ delayed() -> add(FP, lock_offset+STACK_BIAS, L3_box);

     // None of the above fast optimizations worked so we have to get into the

     // slow case of monitor enter.  Inline a special case of call_VM that

     // disallows any pending_exception.

     __ mov(Roop, O0);            // Need oop in O0

     __ mov(L3_box, O1);

     // Record last_Java_sp, in case the VM code releases the JVM lock.

     __ set_last_Java_frame(FP, I7);

     // do the call

     __ call(CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_locking_C), relocInfo::runtime_call_type);

     __ delayed()->mov(L7_thread_cache, O2);

     __ restore_thread(L7_thread_cache); // restore G2_thread

     __ reset_last_Java_frame();

 #ifdef ASSERT

     { Label L;

     __ ld_ptr(G2_thread, in_bytes(Thread::pending_exception_offset()), O0);

     __ br_null_short(O0, Assembler::pt, L);

     __ stop("no pending exception allowed on exit from IR::monitorenter");

     __ bind(L);

     }

 #endif

     __ bind(done);

   }

   // Finally just about ready to make the JNI call

   __ flush_windows();

   if (inner_frame_created) {

     __ restore();

   } else {

     // Store only what we need from this frame

     // QQQ I think that non-v9 (like we care) we don't need these saves

     // either as the flush traps and the current window goes too.

     __ st_ptr(FP, SP, FP->sp_offset_in_saved_window()*wordSize + STACK_BIAS);

     __ st_ptr(I7, SP, I7->sp_offset_in_saved_window()*wordSize + STACK_BIAS);

   }

   // get JNIEnv* which is first argument to native

   if (!is_critical_native) {

     __ add(G2_thread, in_bytes(JavaThread::jni_environment_offset()), O0);

   }

   // Use that pc we placed in O7 a while back as the current frame anchor

   __ set_last_Java_frame(SP, O7);

   // We flushed the windows ages ago now mark them as flushed before transitioning.

   __ set(JavaFrameAnchor::flushed, G3_scratch);

   __ st(G3_scratch, G2_thread, JavaThread::frame_anchor_offset() + JavaFrameAnchor::flags_offset());

   // Transition from _thread_in_Java to _thread_in_native.

   __ set(_thread_in_native, G3_scratch);

 #ifdef _LP64

   AddressLiteral dest(native_func);

   __ relocate(relocInfo::runtime_call_type);

   __ jumpl_to(dest, O7, O7);

 #else

   __ call(native_func, relocInfo::runtime_call_type);

 #endif

   __ delayed()->st(G3_scratch, G2_thread, JavaThread::thread_state_offset());

   __ restore_thread(L7_thread_cache); // restore G2_thread

   // Unpack native results.  For int-types, we do any needed sign-extension

   // and move things into I0.  The return value there will survive any VM

   // calls for blocking or unlocking.  An FP or OOP result (handle) is done

   // specially in the slow-path code.

   switch (ret_type) {

   case T_VOID:    break;        // Nothing to do!

   case T_FLOAT:   break;        // Got it where we want it (unless slow-path)

   case T_DOUBLE:  break;        // Got it where we want it (unless slow-path)

   // In 64 bits build result is in O0, in O0, O1 in 32bit build

   case T_LONG:

 #ifndef _LP64

                   __ mov(O1, I1);

 #endif

                   // Fall thru

   case T_OBJECT:                // Really a handle

   case T_ARRAY:

   case T_INT:

                   __ mov(O0, I0);

                   break;

   case T_BOOLEAN: __ subcc(G0, O0, G0); __ addc(G0, 0, I0); break; // !0 => true; 0 => false

   case T_BYTE   : __ sll(O0, 24, O0); __ sra(O0, 24, I0);   break;

   case T_CHAR   : __ sll(O0, 16, O0); __ srl(O0, 16, I0);   break; // cannot use and3, 0xFFFF too big as immediate value!

   case T_SHORT  : __ sll(O0, 16, O0); __ sra(O0, 16, I0);   break;

     break;                      // Cannot de-handlize until after reclaiming jvm_lock

   default:

     ShouldNotReachHere();

   }

   Label after_transition;

   // must we block?

   // Block, if necessary, before resuming in _thread_in_Java state.

   // In order for GC to work, don't clear the last_Java_sp until after blocking.

   { Label no_block;

     AddressLiteral sync_state(SafepointSynchronize::address_of_state());

     // Switch thread to "native transition" state before reading the synchronization state.

     // This additional state is necessary because reading and testing the synchronization

     // state is not atomic w.r.t. GC, as this scenario demonstrates:

     //     Java thread A, in _thread_in_native state, loads _not_synchronized and is preempted.

     //     VM thread changes sync state to synchronizing and suspends threads for GC.

     //     Thread A is resumed to finish this native method, but doesn't block here since it

     //     didn't see any synchronization is progress, and escapes.

     __ set(_thread_in_native_trans, G3_scratch);

     __ st(G3_scratch, G2_thread, JavaThread::thread_state_offset());

     if(os::is_MP()) {

       if (UseMembar) {

         // Force this write out before the read below

         __ membar(Assembler::StoreLoad);

       } else {

         // Write serialization page so VM thread can do a pseudo remote membar.

         // We use the current thread pointer to calculate a thread specific

         // offset to write to within the page. This minimizes bus traffic

         // due to cache line collision.

         __ serialize_memory(G2_thread, G1_scratch, G3_scratch);

       }

     }

     __ load_contents(sync_state, G3_scratch);

     __ cmp(G3_scratch, SafepointSynchronize::_not_synchronized);

     Label L;

     Address suspend_state(G2_thread, JavaThread::suspend_flags_offset());

     __ br(Assembler::notEqual, false, Assembler::pn, L);

     __ delayed()->ld(suspend_state, G3_scratch);

     __ cmp_and_br_short(G3_scratch, 0, Assembler::equal, Assembler::pt, no_block);

     __ bind(L);

     // Block.  Save any potential method result value before the operation and

     // use a leaf call to leave the last_Java_frame setup undisturbed. Doing this

     // lets us share the oopMap we used when we went native rather the create

     // a distinct one for this pc

     //

     save_native_result(masm, ret_type, stack_slots);

     if (!is_critical_native) {

       __ call_VM_leaf(L7_thread_cache,

                       CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans),

                       G2_thread);

     } else {

       __ call_VM_leaf(L7_thread_cache,

                       CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans_and_transition),

                       G2_thread);

     }

     // Restore any method result value

     restore_native_result(masm, ret_type, stack_slots);

     if (is_critical_native) {

       // The call above performed the transition to thread_in_Java so

       // skip the transition logic below.

       __ ba(after_transition);

       __ delayed()->nop();

     }

     __ bind(no_block);

   }

   // thread state is thread_in_native_trans. Any safepoint blocking has already

   // happened so we can now change state to _thread_in_Java.

   __ set(_thread_in_Java, G3_scratch);

   __ st(G3_scratch, G2_thread, JavaThread::thread_state_offset());

   __ bind(after_transition);

   Label no_reguard;

   __ ld(G2_thread, JavaThread::stack_guard_state_offset(), G3_scratch);

   __ cmp_and_br_short(G3_scratch, JavaThread::stack_guard_yellow_disabled, Assembler::notEqual, Assembler::pt, no_reguard);

     save_native_result(masm, ret_type, stack_slots);

   __ call(CAST_FROM_FN_PTR(address, SharedRuntime::reguard_yellow_pages));

   __ delayed()->nop();

   __ restore_thread(L7_thread_cache); // restore G2_thread

     restore_native_result(masm, ret_type, stack_slots);

   __ bind(no_reguard);

   // Handle possible exception (will unlock if necessary)

   // native result if any is live in freg or I0 (and I1 if long and 32bit vm)

   // Unlock

   if (method->is_synchronized()) {

     Label done;

     Register I2_ex_oop = I2;

     const Register L3_box = L3;

     // Get locked oop from the handle we passed to jni

     __ ld_ptr(L6_handle, 0, L4);

     __ add(SP, lock_offset+STACK_BIAS, L3_box);

     // Must save pending exception around the slow-path VM call.  Since it's a

     // leaf call, the pending exception (if any) can be kept in a register.

     __ ld_ptr(G2_thread, in_bytes(Thread::pending_exception_offset()), I2_ex_oop);

     // Now unlock

     //                       (Roop, Rmark, Rbox,   Rscratch)

     __ compiler_unlock_object(L4,   L1,    L3_box, L2);

     __ br(Assembler::equal, false, Assembler::pt, done);

     __ delayed()-> add(SP, lock_offset+STACK_BIAS, L3_box);

     // save and restore any potential method result value around the unlocking

     // operation.  Will save in I0 (or stack for FP returns).

     save_native_result(masm, ret_type, stack_slots);

     // Must clear pending-exception before re-entering the VM.  Since this is

     // a leaf call, pending-exception-oop can be safely kept in a register.

     __ st_ptr(G0, G2_thread, in_bytes(Thread::pending_exception_offset()));

     // slow case of monitor enter.  Inline a special case of call_VM that

     // disallows any pending_exception.

     __ mov(L3_box, O1);

     __ call(CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C), relocInfo::runtime_call_type);

     __ delayed()->mov(L4, O0);              // Need oop in O0

     __ restore_thread(L7_thread_cache); // restore G2_thread

 #ifdef ASSERT