jdk8-mips64-public/hotspot: src/cpu/x86/vm/sharedRuntime_x86

src/cpu/x86/vm/sharedRuntime_x86_32.cpp@8a02ca5e5576 (annotated)

src/cpu/x86/vm/sharedRuntime_x86_32.cpp

Tue, 11 Sep 2012 16:20:57 +0200

author: roland
date: Tue, 11 Sep 2012 16:20:57 +0200
changeset 4051: 8a02ca5e5576
parent 4037: da91efe96a93
child 4101: 2cb2f30450c7
permissions: -rw-r--r--

7195816: NPG: Crash in c1_ValueType - ShouldNotReachHere
Summary: C1 needs knowledge of T_METADATA at the LIR level.
Reviewed-by: kvn, coleenp

 /*
  * 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_x86.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_x86.inline.hpp"
 #ifdef COMPILER1
 #include "c1/c1_Runtime1.hpp"
 #endif
 #ifdef COMPILER2
 #include "opto/runtime.hpp"
 #endif
 #define __ masm->
 const int StackAlignmentInSlots = StackAlignmentInBytes / VMRegImpl::stack_slot_size;
 class RegisterSaver {
   enum { FPU_regs_live = 8 /*for the FPU stack*/+8/*eight more for XMM registers*/ };
   // Capture info about frame layout
   enum layout {
                 fpu_state_off = 0,
                 fpu_state_end = fpu_state_off+FPUStateSizeInWords-1,
                 st0_off, st0H_off,
                 st1_off, st1H_off,
                 st2_off, st2H_off,
                 st3_off, st3H_off,
                 st4_off, st4H_off,
                 st5_off, st5H_off,
                 st6_off, st6H_off,
                 st7_off, st7H_off,
                 xmm0_off, xmm0H_off,
                 xmm1_off, xmm1H_off,
                 xmm2_off, xmm2H_off,
                 xmm3_off, xmm3H_off,
                 xmm4_off, xmm4H_off,
                 xmm5_off, xmm5H_off,
                 xmm6_off, xmm6H_off,
                 xmm7_off, xmm7H_off,
                 flags_off,
                 rdi_off,
                 rsi_off,
                 ignore_off,  // extra copy of rbp,
                 rsp_off,
                 rbx_off,
                 rdx_off,
                 rcx_off,
                 rax_off,
                 // The frame sender code expects that rbp will be in the "natural" place and
                 // will override any oopMap setting for it. We must therefore force the layout
                 // so that it agrees with the frame sender code.
                 rbp_off,
                 return_off,      // slot for return address
                 reg_save_size };
   public:
   static OopMap* save_live_registers(MacroAssembler* masm, int additional_frame_words,
                                      int* total_frame_words, bool verify_fpu = true);
   static void restore_live_registers(MacroAssembler* masm);
   static int rax_offset() { return rax_off; }
   static int rbx_offset() { return rbx_off; }
   // Offsets into the register save area
   // Used by deoptimization when it is managing result register
   // values on its own
   static int raxOffset(void) { return rax_off; }
   static int rdxOffset(void) { return rdx_off; }
   static int rbxOffset(void) { return rbx_off; }
   static int xmm0Offset(void) { return xmm0_off; }
   // This really returns a slot in the fp save area, which one is not important
   static int fpResultOffset(void) { return st0_off; }
   // 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, bool verify_fpu) {
   int frame_size_in_bytes =  (reg_save_size + additional_frame_words) * wordSize;
   int frame_words = frame_size_in_bytes / wordSize;
   *total_frame_words = frame_words;
   assert(FPUStateSizeInWords == 27, "update stack layout");
   // save registers, fpu state, and flags
   // We assume caller has already has return address slot on the stack
   // We push epb twice in this sequence because we want the real rbp,
   // to be under the return like a normal enter and we want to use pusha
   // We push by hand instead of pusing push
   __ enter();
   __ pusha();
   __ pushf();
   __ subptr(rsp,FPU_regs_live*sizeof(jdouble)); // Push FPU registers space
   __ push_FPU_state();          // Save FPU state & init
   if (verify_fpu) {
     // Some stubs may have non standard FPU control word settings so
     // only check and reset the value when it required to be the
     // standard value.  The safepoint blob in particular can be used
     // in methods which are using the 24 bit control word for
     // optimized float math.
 #ifdef ASSERT
     // Make sure the control word has the expected value
     Label ok;
     __ cmpw(Address(rsp, 0), StubRoutines::fpu_cntrl_wrd_std());
     __ jccb(Assembler::equal, ok);
     __ stop("corrupted control word detected");
     __ bind(ok);
 #endif
     // Reset the control word to guard against exceptions being unmasked
     // since fstp_d can cause FPU stack underflow exceptions.  Write it
     // into the on stack copy and then reload that to make sure that the
     // current and future values are correct.
     __ movw(Address(rsp, 0), StubRoutines::fpu_cntrl_wrd_std());
   }
   __ frstor(Address(rsp, 0));
   if (!verify_fpu) {
     // Set the control word so that exceptions are masked for the
     // following code.
     __ fldcw(ExternalAddress(StubRoutines::addr_fpu_cntrl_wrd_std()));
   }
   // Save the FPU registers in de-opt-able form
   __ fstp_d(Address(rsp, st0_off*wordSize)); // st(0)
   __ fstp_d(Address(rsp, st1_off*wordSize)); // st(1)
   __ fstp_d(Address(rsp, st2_off*wordSize)); // st(2)
   __ fstp_d(Address(rsp, st3_off*wordSize)); // st(3)
   __ fstp_d(Address(rsp, st4_off*wordSize)); // st(4)
   __ fstp_d(Address(rsp, st5_off*wordSize)); // st(5)
   __ fstp_d(Address(rsp, st6_off*wordSize)); // st(6)
   __ fstp_d(Address(rsp, st7_off*wordSize)); // st(7)
   if( UseSSE == 1 ) {           // Save the XMM state
     __ movflt(Address(rsp,xmm0_off*wordSize),xmm0);
     __ movflt(Address(rsp,xmm1_off*wordSize),xmm1);
     __ movflt(Address(rsp,xmm2_off*wordSize),xmm2);
     __ movflt(Address(rsp,xmm3_off*wordSize),xmm3);
     __ movflt(Address(rsp,xmm4_off*wordSize),xmm4);
     __ movflt(Address(rsp,xmm5_off*wordSize),xmm5);
     __ movflt(Address(rsp,xmm6_off*wordSize),xmm6);
     __ movflt(Address(rsp,xmm7_off*wordSize),xmm7);
   } else if( UseSSE >= 2 ) {
     __ movdbl(Address(rsp,xmm0_off*wordSize),xmm0);
     __ movdbl(Address(rsp,xmm1_off*wordSize),xmm1);
     __ movdbl(Address(rsp,xmm2_off*wordSize),xmm2);
     __ movdbl(Address(rsp,xmm3_off*wordSize),xmm3);
     __ movdbl(Address(rsp,xmm4_off*wordSize),xmm4);
     __ movdbl(Address(rsp,xmm5_off*wordSize),xmm5);
     __ movdbl(Address(rsp,xmm6_off*wordSize),xmm6);
     __ movdbl(Address(rsp,xmm7_off*wordSize),xmm7);
   }
   // Set an oopmap for the call site.  This oopmap will map all
   // oop-registers and debug-info registers as callee-saved.  This
   // will allow deoptimization at this safepoint to find all possible
   // debug-info recordings, as well as let GC find all oops.
   OopMapSet *oop_maps = new OopMapSet();
   OopMap* map =  new OopMap( frame_words, 0 );
 #define STACK_OFFSET(x) VMRegImpl::stack2reg((x) + additional_frame_words)
   map->set_callee_saved(STACK_OFFSET( rax_off), rax->as_VMReg());
   map->set_callee_saved(STACK_OFFSET( rcx_off), rcx->as_VMReg());
   map->set_callee_saved(STACK_OFFSET( rdx_off), rdx->as_VMReg());
   map->set_callee_saved(STACK_OFFSET( rbx_off), rbx->as_VMReg());
   // rbp, location is known implicitly, no oopMap
   map->set_callee_saved(STACK_OFFSET( rsi_off), rsi->as_VMReg());
   map->set_callee_saved(STACK_OFFSET( rdi_off), rdi->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(st0_off), as_FloatRegister(0)->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(st1_off), as_FloatRegister(1)->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(st2_off), as_FloatRegister(2)->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(st3_off), as_FloatRegister(3)->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(st4_off), as_FloatRegister(4)->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(st5_off), as_FloatRegister(5)->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(st6_off), as_FloatRegister(6)->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(st7_off), as_FloatRegister(7)->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(xmm0_off), xmm0->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(xmm1_off), xmm1->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(xmm2_off), xmm2->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(xmm3_off), xmm3->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(xmm4_off), xmm4->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(xmm5_off), xmm5->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(xmm6_off), xmm6->as_VMReg());
   map->set_callee_saved(STACK_OFFSET(xmm7_off), xmm7->as_VMReg());
   // %%% This is really a waste but we'll keep things as they were for now
   if (true) {
 #define NEXTREG(x) (x)->as_VMReg()->next()
     map->set_callee_saved(STACK_OFFSET(st0H_off), NEXTREG(as_FloatRegister(0)));
     map->set_callee_saved(STACK_OFFSET(st1H_off), NEXTREG(as_FloatRegister(1)));
     map->set_callee_saved(STACK_OFFSET(st2H_off), NEXTREG(as_FloatRegister(2)));
     map->set_callee_saved(STACK_OFFSET(st3H_off), NEXTREG(as_FloatRegister(3)));
     map->set_callee_saved(STACK_OFFSET(st4H_off), NEXTREG(as_FloatRegister(4)));
     map->set_callee_saved(STACK_OFFSET(st5H_off), NEXTREG(as_FloatRegister(5)));
     map->set_callee_saved(STACK_OFFSET(st6H_off), NEXTREG(as_FloatRegister(6)));
     map->set_callee_saved(STACK_OFFSET(st7H_off), NEXTREG(as_FloatRegister(7)));
     map->set_callee_saved(STACK_OFFSET(xmm0H_off), NEXTREG(xmm0));
     map->set_callee_saved(STACK_OFFSET(xmm1H_off), NEXTREG(xmm1));
     map->set_callee_saved(STACK_OFFSET(xmm2H_off), NEXTREG(xmm2));
     map->set_callee_saved(STACK_OFFSET(xmm3H_off), NEXTREG(xmm3));
     map->set_callee_saved(STACK_OFFSET(xmm4H_off), NEXTREG(xmm4));
     map->set_callee_saved(STACK_OFFSET(xmm5H_off), NEXTREG(xmm5));
     map->set_callee_saved(STACK_OFFSET(xmm6H_off), NEXTREG(xmm6));
     map->set_callee_saved(STACK_OFFSET(xmm7H_off), NEXTREG(xmm7));
 #undef NEXTREG
 #undef STACK_OFFSET
   }
   return map;
 }
 void RegisterSaver::restore_live_registers(MacroAssembler* masm) {
   // Recover XMM & FPU state
   if( UseSSE == 1 ) {
     __ movflt(xmm0,Address(rsp,xmm0_off*wordSize));
     __ movflt(xmm1,Address(rsp,xmm1_off*wordSize));
     __ movflt(xmm2,Address(rsp,xmm2_off*wordSize));
     __ movflt(xmm3,Address(rsp,xmm3_off*wordSize));
     __ movflt(xmm4,Address(rsp,xmm4_off*wordSize));
     __ movflt(xmm5,Address(rsp,xmm5_off*wordSize));
     __ movflt(xmm6,Address(rsp,xmm6_off*wordSize));
     __ movflt(xmm7,Address(rsp,xmm7_off*wordSize));
   } else if( UseSSE >= 2 ) {
     __ movdbl(xmm0,Address(rsp,xmm0_off*wordSize));
     __ movdbl(xmm1,Address(rsp,xmm1_off*wordSize));
     __ movdbl(xmm2,Address(rsp,xmm2_off*wordSize));
     __ movdbl(xmm3,Address(rsp,xmm3_off*wordSize));
     __ movdbl(xmm4,Address(rsp,xmm4_off*wordSize));
     __ movdbl(xmm5,Address(rsp,xmm5_off*wordSize));
     __ movdbl(xmm6,Address(rsp,xmm6_off*wordSize));
     __ movdbl(xmm7,Address(rsp,xmm7_off*wordSize));
   }
   __ pop_FPU_state();
   __ addptr(rsp, FPU_regs_live*sizeof(jdouble)); // Pop FPU registers
   __ popf();
   __ popa();
   // Get the rbp, described implicitly by the frame sender code (no oopMap)
   __ pop(rbp);
 }
 void RegisterSaver::restore_result_registers(MacroAssembler* masm) {
   // Just restore result register. Only used by deoptimization. By
   // now any callee save register that needs to be restore to a c2
   // caller of the deoptee has been extracted into the vframeArray
   // and will be stuffed into the c2i adapter we create for later
   // restoration so only result registers need to be restored here.
   //
   __ frstor(Address(rsp, 0));      // Restore fpu state
   // Recover XMM & FPU state
   if( UseSSE == 1 ) {
     __ movflt(xmm0, Address(rsp, xmm0_off*wordSize));
   } else if( UseSSE >= 2 ) {
     __ movdbl(xmm0, Address(rsp, xmm0_off*wordSize));
   }
   __ movptr(rax, Address(rsp, rax_off*wordSize));
   __ movptr(rdx, Address(rsp, rdx_off*wordSize));
   // Pop all of the register save are off the stack except the return address
   __ addptr(rsp, return_off * wordSize);
 }
 // 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_in(VMReg r) {
   // Account for saved rbp, and return address
   // This should really be in_preserve_stack_slots
   return (r->reg2stack() + 2) * VMRegImpl::stack_slot_size;
 }
 static int reg2offset_out(VMReg r) {
   return (r->reg2stack() + SharedRuntime::out_preserve_stack_slots()) * VMRegImpl::stack_slot_size;
 }
 // ---------------------------------------------------------------------------
 // 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
 // quantities.  Values less than SharedInfo::stack0 are registers, those above
 // refer to 4-byte stack slots.  All stack slots are based off of the stack pointer
 // as framesizes are fixed.
 // VMRegImpl::stack0 refers to the first slot 0(sp).
 // and VMRegImpl::stack0+1 refers to the memory word 4-byes higher.  Register
 // up to RegisterImpl::number_of_registers) are the 32-bit
 // integer registers.
 // Pass first two oop/int args in registers ECX and EDX.
 // Pass first two float/double args in registers XMM0 and XMM1.
 // Doubles have precedence, so if you pass a mix of floats and doubles
 // the doubles will grab the registers before the floats will.
 // 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. Of course for i486 there is no 64 bit build
 // ---------------------------------------------------------------------------
 // The compiled Java calling convention.
 // Pass first two oop/int args in registers ECX and EDX.
 // Pass first two float/double args in registers XMM0 and XMM1.
 // Doubles have precedence, so if you pass a mix of floats and doubles
 // the doubles will grab the registers before the floats will.
 int SharedRuntime::java_calling_convention(const BasicType *sig_bt,
                                            VMRegPair *regs,
                                            int total_args_passed,
                                            int is_outgoing) {
   uint    stack = 0;          // Starting stack position for args on stack
   // Pass first two oop/int args in registers ECX and EDX.
   uint reg_arg0 = 9999;
   uint reg_arg1 = 9999;
   // Pass first two float/double args in registers XMM0 and XMM1.
   // Doubles have precedence, so if you pass a mix of floats and doubles
   // the doubles will grab the registers before the floats will.
   // CNC - TURNED OFF FOR non-SSE.
   //       On Intel we have to round all doubles (and most floats) at
   //       call sites by storing to the stack in any case.
   // UseSSE=0 ==> Don't Use ==> 9999+0
   // UseSSE=1 ==> Floats only ==> 9999+1
   // UseSSE>=2 ==> Floats or doubles ==> 9999+2
   enum { fltarg_dontuse = 9999+0, fltarg_float_only = 9999+1, fltarg_flt_dbl = 9999+2 };
   uint fargs = (UseSSE>=2) ? 2 : UseSSE;
   uint freg_arg0 = 9999+fargs;
   uint freg_arg1 = 9999+fargs;
   // Pass doubles & longs aligned on the stack.  First count stack slots for doubles
   int i;
   for( i = 0; i < total_args_passed; i++) {
     if( sig_bt[i] == T_DOUBLE ) {
       // first 2 doubles go in registers
       if( freg_arg0 == fltarg_flt_dbl ) freg_arg0 = i;
       else if( freg_arg1 == fltarg_flt_dbl ) freg_arg1 = i;
       else // Else double is passed low on the stack to be aligned.
         stack += 2;
     } else if( sig_bt[i] == T_LONG ) {
       stack += 2;
     }
   }
   int dstack = 0;             // Separate counter for placing doubles
   // Now pick where all else goes.
   for( i = 0; i < total_args_passed; i++) {
     // From the type and the argument number (count) compute the location
     switch( sig_bt[i] ) {
     case T_SHORT:
     case T_CHAR:
     case T_BYTE:
     case T_BOOLEAN:
     case T_INT:
     case T_ARRAY:
     case T_OBJECT:
     case T_ADDRESS:
       if( reg_arg0 == 9999 )  {
         reg_arg0 = i;
         regs[i].set1(rcx->as_VMReg());
       } else if( reg_arg1 == 9999 )  {
         reg_arg1 = i;
         regs[i].set1(rdx->as_VMReg());
       } else {
         regs[i].set1(VMRegImpl::stack2reg(stack++));
       }
       break;
     case T_FLOAT:
       if( freg_arg0 == fltarg_flt_dbl || freg_arg0 == fltarg_float_only ) {
         freg_arg0 = i;
         regs[i].set1(xmm0->as_VMReg());
       } else if( freg_arg1 == fltarg_flt_dbl || freg_arg1 == fltarg_float_only ) {
         freg_arg1 = i;
         regs[i].set1(xmm1->as_VMReg());
       } else {
         regs[i].set1(VMRegImpl::stack2reg(stack++));
       }
       break;
     case T_LONG:
       assert(sig_bt[i+1] == T_VOID, "missing Half" );
       regs[i].set2(VMRegImpl::stack2reg(dstack));
       dstack += 2;
       break;
     case T_DOUBLE:
       assert(sig_bt[i+1] == T_VOID, "missing Half" );
       if( freg_arg0 == (uint)i ) {
         regs[i].set2(xmm0->as_VMReg());
       } else if( freg_arg1 == (uint)i ) {
         regs[i].set2(xmm1->as_VMReg());
       } else {
         regs[i].set2(VMRegImpl::stack2reg(dstack));
         dstack += 2;
       }
       break;
     case T_VOID: regs[i].set_bad(); break;
       break;
     default:
       ShouldNotReachHere();
       break;
     }
   }
   // return value can be odd number of VMRegImpl stack slots make multiple of 2
   return round_to(stack, 2);
 }
 // Patch the callers callsite with entry to compiled code if it exists.
 static void patch_callers_callsite(MacroAssembler *masm) {
   Label L;
   __ cmpptr(Address(rbx, in_bytes(Method::code_offset())), (int32_t)NULL_WORD);
   __ jcc(Assembler::equal, L);
   // Schedule the branch target address early.
   // Call into the VM to patch the caller, then jump to compiled callee
   // rax, isn't live so capture return address while we easily can
   __ movptr(rax, Address(rsp, 0));
   __ pusha();
   __ pushf();
   if (UseSSE == 1) {
     __ subptr(rsp, 2*wordSize);
     __ movflt(Address(rsp, 0), xmm0);
     __ movflt(Address(rsp, wordSize), xmm1);
   }
   if (UseSSE >= 2) {
     __ subptr(rsp, 4*wordSize);
     __ movdbl(Address(rsp, 0), xmm0);
     __ movdbl(Address(rsp, 2*wordSize), xmm1);
   }
 #ifdef COMPILER2
   // C2 may leave the stack dirty if not in SSE2+ mode
   if (UseSSE >= 2) {
     __ verify_FPU(0, "c2i transition should have clean FPU stack");
   } else {
     __ empty_FPU_stack();
   }
 #endif /* COMPILER2 */
   // VM needs caller's callsite
   __ push(rax);
   // VM needs target method
   __ push(rbx);
   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::fixup_callers_callsite)));
   __ addptr(rsp, 2*wordSize);
   if (UseSSE == 1) {
     __ movflt(xmm0, Address(rsp, 0));
     __ movflt(xmm1, Address(rsp, wordSize));
     __ addptr(rsp, 2*wordSize);
   }
   if (UseSSE >= 2) {
     __ movdbl(xmm0, Address(rsp, 0));
     __ movdbl(xmm1, Address(rsp, 2*wordSize));
     __ addptr(rsp, 4*wordSize);
   }
   __ popf();
   __ popa();
   __ bind(L);
 }
 static void move_c2i_double(MacroAssembler *masm, XMMRegister r, int st_off) {
   int next_off = st_off - Interpreter::stackElementSize;
   __ movdbl(Address(rsp, next_off), r);
 }
 static void gen_c2i_adapter(MacroAssembler *masm,
                             int total_args_passed,
                             int comp_args_on_stack,
                             const BasicType *sig_bt,
                             const VMRegPair *regs,
                             Label& 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.
   patch_callers_callsite(masm);
   __ bind(skip_fixup);
 #ifdef COMPILER2
   // C2 may leave the stack dirty if not in SSE2+ mode
   if (UseSSE >= 2) {
     __ verify_FPU(0, "c2i transition should have clean FPU stack");
   } else {
     __ empty_FPU_stack();
   }
 #endif /* COMPILER2 */
   // Since all args are passed on the stack, total_args_passed * interpreter_
   // stack_element_size  is the
   // space we need.
   int extraspace = total_args_passed * Interpreter::stackElementSize;
   // Get return address
   __ pop(rax);
   // set senderSP value
   __ movptr(rsi, rsp);
   __ subptr(rsp, extraspace);
   // Now write the args into the outgoing interpreter space
   for (int i = 0; i < total_args_passed; i++) {
     if (sig_bt[i] == T_VOID) {
       assert(i > 0 && (sig_bt[i-1] == T_LONG || sig_bt[i-1] == T_DOUBLE), "missing half");
       continue;
     }
     // st_off points to lowest address on stack.
     int st_off = ((total_args_passed - 1) - i) * Interpreter::stackElementSize;
     int next_off = st_off - Interpreter::stackElementSize;
     // Say 4 args:
     // i   st_off
     // 0   12 T_LONG
     // 1    8 T_VOID
     // 2    4 T_OBJECT
     // 3    0 T_BOOL
     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()) {
       // memory to memory use fpu stack top
       int ld_off = r_1->reg2stack() * VMRegImpl::stack_slot_size + extraspace;
       if (!r_2->is_valid()) {
         __ movl(rdi, Address(rsp, ld_off));
         __ movptr(Address(rsp, st_off), rdi);
       } else {
         // ld_off == LSW, ld_off+VMRegImpl::stack_slot_size == MSW
         // st_off == MSW, st_off-wordSize == LSW
         __ movptr(rdi, Address(rsp, ld_off));
         __ movptr(Address(rsp, next_off), rdi);
 #ifndef _LP64
         __ movptr(rdi, Address(rsp, ld_off + wordSize));
         __ movptr(Address(rsp, st_off), rdi);
 #else
 #ifdef ASSERT
         // Overwrite the unused slot with known junk
         __ mov64(rax, CONST64(0xdeadffffdeadaaaa));
         __ movptr(Address(rsp, st_off), rax);
 #endif /* ASSERT */
 #endif // _LP64
       }
     } else if (r_1->is_Register()) {
       Register r = r_1->as_Register();
       if (!r_2->is_valid()) {
         __ movl(Address(rsp, st_off), r);
       } else {
         // long/double in gpr
         NOT_LP64(ShouldNotReachHere());
         // Two VMRegs can be T_OBJECT, T_ADDRESS, T_DOUBLE, T_LONG
         // T_DOUBLE and T_LONG use two slots in the interpreter
         if ( sig_bt[i] == T_LONG || sig_bt[i] == T_DOUBLE) {
           // long/double in gpr
 #ifdef ASSERT
           // Overwrite the unused slot with known junk
           LP64_ONLY(__ mov64(rax, CONST64(0xdeadffffdeadaaab)));
           __ movptr(Address(rsp, st_off), rax);
 #endif /* ASSERT */
           __ movptr(Address(rsp, next_off), r);
         } else {
           __ movptr(Address(rsp, st_off), r);
         }
       }
     } else {
       assert(r_1->is_XMMRegister(), "");
       if (!r_2->is_valid()) {
         __ movflt(Address(rsp, st_off), r_1->as_XMMRegister());
       } else {
         assert(sig_bt[i] == T_DOUBLE || sig_bt[i] == T_LONG, "wrong type");
         move_c2i_double(masm, r_1->as_XMMRegister(), st_off);
       }
     }
   }
   // Schedule the branch target address early.
   __ movptr(rcx, Address(rbx, in_bytes(Method::interpreter_entry_offset())));
   // And repush original return address
   __ push(rax);
   __ jmp(rcx);
 }
 static void move_i2c_double(MacroAssembler *masm, XMMRegister r, Register saved_sp, int ld_off) {
   int next_val_off = ld_off - Interpreter::stackElementSize;
   __ movdbl(r, Address(saved_sp, next_val_off));
 }
 static void range_check(MacroAssembler* masm, Register pc_reg, Register temp_reg,
                         address code_start, address code_end,
                         Label& L_ok) {
   Label L_fail;
   __ lea(temp_reg, ExternalAddress(code_start));
   __ cmpptr(pc_reg, temp_reg);
   __ jcc(Assembler::belowEqual, L_fail);
   __ lea(temp_reg, ExternalAddress(code_end));
   __ cmpptr(pc_reg, temp_reg);
   __ jcc(Assembler::below, L_ok);
   __ bind(L_fail);
 }
 static void gen_i2c_adapter(MacroAssembler *masm,
                             int total_args_passed,
                             int comp_args_on_stack,
                             const BasicType *sig_bt,
                             const VMRegPair *regs) {
   // Note: rsi contains the senderSP on entry. We must preserve it since
   // we may do a i2c -> c2i transition if we lose a race where compiled
   // code goes non-entrant while we get args ready.
   // 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.
   // Pick up the return address
   __ movptr(rax, Address(rsp, 0));
   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, rax, rdi,
                   Interpreter::code()->code_start(), Interpreter::code()->code_end(),
                   L_ok);
     if (StubRoutines::code1() != NULL)
       range_check(masm, rax, rdi,
                   StubRoutines::code1()->code_begin(), StubRoutines::code1()->code_end(),
                   L_ok);
     if (StubRoutines::code2() != NULL)
       range_check(masm, rax, rdi,
                   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 ");
   }
   // Must preserve original SP for loading incoming arguments because
   // we need to align the outgoing SP for compiled code.
   __ movptr(rdi, rsp);
   // Cut-out for having no stack args.  Since up to 2 int/oop args are passed
   // in registers, we will occasionally have no stack args.
   int comp_words_on_stack = 0;
   if (comp_args_on_stack) {
     // Sig words on the stack are greater-than VMRegImpl::stack0.  Those in
     // registers are below.  By subtracting stack0, we either get a negative
     // number (all values in registers) or the maximum stack slot accessed.
     // int comp_args_on_stack = VMRegImpl::reg2stack(max_arg);
     // Convert 4-byte stack slots to words.
     comp_words_on_stack = round_to(comp_args_on_stack*4, wordSize)>>LogBytesPerWord;
     // Round up to miminum stack alignment, in wordSize
     comp_words_on_stack = round_to(comp_words_on_stack, 2);
     __ subptr(rsp, comp_words_on_stack * wordSize);
   }
   // Align the outgoing SP
   __ andptr(rsp, -(StackAlignmentInBytes));
   // push the return address on the stack (note that pushing, rather
   // than storing it, yields the correct frame alignment for the callee)
   __ push(rax);
   // Put saved SP in another register
   const Register saved_sp = rax;
   __ movptr(saved_sp, rdi);
   // Will jump to the compiled code just as if compiled code was doing it.
   // Pre-load the register-jump target early, to schedule it better.
   __ movptr(rdi, Address(rbx, in_bytes(Method::from_compiled_offset())));
   // Now generate the shuffle code.  Pick up all register args and move the
   // rest through the floating point stack top.
   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 SP+offset.
     assert(!regs[i].second()->is_valid() || regs[i].first()->next() == regs[i].second(),
             "scrambled load targets?");
     // Load in argument order going down.
     int ld_off = (total_args_passed - i) * Interpreter::stackElementSize;
     // Point to interpreter value (vs. tag)
     int next_off = ld_off - Interpreter::stackElementSize;
     //
     //
     //
     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()) {
       // Convert stack slot to an SP offset (+ wordSize to account for return address )
       int st_off = regs[i].first()->reg2stack()*VMRegImpl::stack_slot_size + wordSize;
       // We can use rsi as a temp here because compiled code doesn't need rsi as an input
       // and if we end up going thru a c2i because of a miss a reasonable value of rsi
       // we be generated.
       if (!r_2->is_valid()) {
         // __ fld_s(Address(saved_sp, ld_off));
         // __ fstp_s(Address(rsp, st_off));
         __ movl(rsi, Address(saved_sp, ld_off));
         __ movptr(Address(rsp, st_off), rsi);
       } else {
         // Interpreter local[n] == MSW, local[n+1] == LSW however locals
         // are accessed as negative so LSW is at LOW address
         // ld_off is MSW so get LSW
         // st_off is LSW (i.e. reg.first())
         // __ fld_d(Address(saved_sp, next_off));
         // __ fstp_d(Address(rsp, st_off));
         //
         // We are using two VMRegs. This can be either T_OBJECT, T_ADDRESS, T_LONG, or T_DOUBLE
         // the interpreter allocates two slots but only uses one for thr T_LONG or T_DOUBLE case
         // So we must adjust where to pick up the data to match the interpreter.
         //
         // Interpreter local[n] == MSW, local[n+1] == LSW however locals
         // are accessed as negative so LSW is at LOW address
         // ld_off is MSW so get LSW
         const int offset = (NOT_LP64(true ||) sig_bt[i]==T_LONG||sig_bt[i]==T_DOUBLE)?
                            next_off : ld_off;
         __ movptr(rsi, Address(saved_sp, offset));
         __ movptr(Address(rsp, st_off), rsi);
 #ifndef _LP64
         __ movptr(rsi, Address(saved_sp, ld_off));
         __ movptr(Address(rsp, st_off + wordSize), rsi);
 #endif // _LP64
       }
     } else if (r_1->is_Register()) {  // Register argument
       Register r = r_1->as_Register();
       assert(r != rax, "must be different");
       if (r_2->is_valid()) {
         //
         // We are using two VMRegs. This can be either T_OBJECT, T_ADDRESS, T_LONG, or T_DOUBLE
         // the interpreter allocates two slots but only uses one for thr T_LONG or T_DOUBLE case
         // So we must adjust where to pick up the data to match the interpreter.
         const int offset = (NOT_LP64(true ||) sig_bt[i]==T_LONG||sig_bt[i]==T_DOUBLE)?
                            next_off : ld_off;
         // this can be a misaligned move
         __ movptr(r, Address(saved_sp, offset));
 #ifndef _LP64
         assert(r_2->as_Register() != rax, "need another temporary register");
         // Remember r_1 is low address (and LSB on x86)
         // So r_2 gets loaded from high address regardless of the platform
         __ movptr(r_2->as_Register(), Address(saved_sp, ld_off));
 #endif // _LP64
       } else {
         __ movl(r, Address(saved_sp, ld_off));
       }
     } else {
       assert(r_1->is_XMMRegister(), "");
       if (!r_2->is_valid()) {
         __ movflt(r_1->as_XMMRegister(), Address(saved_sp, ld_off));
       } else {
         move_i2c_double(masm, r_1->as_XMMRegister(), saved_sp, ld_off);
       }
     }
   }
   // 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.
   __ get_thread(rax);
   __ movptr(Address(rax, JavaThread::callee_target_offset()), rbx);
   // move Method* to rax, in case we end up in an c2i adapter.
   // the c2i adapters expect Method* in rax, (c2) because c2's
   // resolve stubs return the result (the method) in rax,.
   // I'd love to fix this.
   __ mov(rax, rbx);
   __ jmp(rdi);
 }
 // ---------------------------------------------------------------
 AdapterHandlerEntry* SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm,
                                                             int total_args_passed,
                                                             int comp_args_on_stack,
                                                             const BasicType *sig_bt,
                                                             const VMRegPair *regs,
                                                             AdapterFingerPrint* fingerprint) {
   address i2c_entry = __ pc();
   gen_i2c_adapter(masm, total_args_passed, comp_args_on_stack, sig_bt, regs);
   // -------------------------------------------------------------------------
   // Generate a C2I adapter.  On entry we know rbx, holds the Method* during calls
   // to the interpreter.  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 EBP, get sick).
   address c2i_unverified_entry = __ pc();
   Label skip_fixup;
   Register holder = rax;
   Register receiver = rcx;
   Register temp = rbx;
   {
     Label missed;
     __ movptr(temp, Address(receiver, oopDesc::klass_offset_in_bytes()));
     __ cmpptr(temp, Address(holder, CompiledICHolder::holder_klass_offset()));
     __ movptr(rbx, Address(holder, CompiledICHolder::holder_method_offset()));
     __ jcc(Assembler::notEqual, missed);
     // 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.
     __ cmpptr(Address(rbx, in_bytes(Method::code_offset())), (int32_t)NULL_WORD);
     __ jcc(Assembler::equal, skip_fixup);
     __ bind(missed);
     __ jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
   }
   address c2i_entry = __ pc();
   gen_c2i_adapter(masm, total_args_passed, comp_args_on_stack, sig_bt, regs, skip_fixup);
   __ flush();
   return AdapterHandlerLibrary::new_entry(fingerprint, i2c_entry, c2i_entry, c2i_unverified_entry);
 }
 int SharedRuntime::c_calling_convention(const BasicType *sig_bt,
                                          VMRegPair *regs,
                                          int total_args_passed) {
 // We return the amount of VMRegImpl stack slots we need to reserve for all
 // the arguments NOT counting out_preserve_stack_slots.
   uint    stack = 0;        // All arguments on stack
   for( int i = 0; i < total_args_passed; i++) {
     // From the type and the argument number (count) compute the location
     switch( sig_bt[i] ) {
     case T_BOOLEAN:
     case T_CHAR:
     case T_FLOAT:
     case T_BYTE:
     case T_SHORT:
     case T_INT:
     case T_OBJECT:
     case T_ARRAY:
     case T_ADDRESS:
     case T_METADATA:
       regs[i].set1(VMRegImpl::stack2reg(stack++));
       break;
     case T_LONG:
     case T_DOUBLE: // The stack numbering is reversed from Java
       // Since C arguments do not get reversed, the ordering for
       // doubles on the stack must be opposite the Java convention
       assert(sig_bt[i+1] == T_VOID, "missing Half" );
       regs[i].set2(VMRegImpl::stack2reg(stack));
       stack += 2;
       break;
     case T_VOID: regs[i].set_bad(); break;
     default:
       ShouldNotReachHere();
       break;
     }
   }
   return stack;
 }
 // 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);
       __ movl2ptr(rax, Address(rbp, reg2offset_in(src.first())));
       __ movptr(Address(rsp, reg2offset_out(dst.first())), rax);
     } else {
       // stack to reg
       __ movl2ptr(dst.first()->as_Register(),  Address(rbp, reg2offset_in(src.first())));
     }
   } else if (dst.first()->is_stack()) {
     // reg to stack
     // no need to sign extend on 64bit
     __ movptr(Address(rsp, reg2offset_out(dst.first())), src.first()->as_Register());
   } else {
     if (dst.first() != src.first()) {
       __ mov(dst.first()->as_Register(), src.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) {
   // Because of the calling conventions we know that src can be a
   // register or a stack location. dst can only be a stack location.
   assert(dst.first()->is_stack(), "must be stack");
   // 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 as an argument
     Register rHandle = rax;
     Label nil;
     __ xorptr(rHandle, rHandle);
     __ cmpptr(Address(rbp, reg2offset_in(src.first())), (int32_t)NULL_WORD);
     __ jcc(Assembler::equal, nil);
     __ lea(rHandle, Address(rbp, reg2offset_in(src.first())));
     __ bind(nil);
     __ movptr(Address(rsp, reg2offset_out(dst.first())), rHandle);
     int offset_in_older_frame = src.first()->reg2stack() + SharedRuntime::out_preserve_stack_slots();
     map->set_oop(VMRegImpl::stack2reg(offset_in_older_frame + framesize_in_slots));
     if (is_receiver) {
       *receiver_offset = (offset_in_older_frame + framesize_in_slots) * VMRegImpl::stack_slot_size;
     }
   } else {
     // Oop is in an a register we must store it to the space we reserve
     // on the stack for oop_handles
     const Register rOop = src.first()->as_Register();
     const Register rHandle = rax;
     int oop_slot = (rOop == rcx ? 0 : 1) * VMRegImpl::slots_per_word + oop_handle_offset;
     int offset = oop_slot*VMRegImpl::stack_slot_size;
     Label skip;
     __ movptr(Address(rsp, offset), rOop);
     map->set_oop(VMRegImpl::stack2reg(oop_slot));
     __ xorptr(rHandle, rHandle);
     __ cmpptr(rOop, (int32_t)NULL_WORD);
     __ jcc(Assembler::equal, skip);
     __ lea(rHandle, Address(rsp, offset));
     __ bind(skip);
     // Store the handle parameter
     __ movptr(Address(rsp, reg2offset_out(dst.first())), rHandle);
     if (is_receiver) {
       *receiver_offset = offset;
     }
   }
 }
 // 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");
   // Because of the calling convention we know that src is either a stack location
   // or an xmm register. dst can only be a stack location.
   assert(dst.first()->is_stack() && ( src.first()->is_stack() || src.first()->is_XMMRegister()), "bad parameters");
   if (src.first()->is_stack()) {
     __ movl(rax, Address(rbp, reg2offset_in(src.first())));
     __ movptr(Address(rsp, reg2offset_out(dst.first())), rax);
   } else {
     // reg to stack
     __ movflt(Address(rsp, reg2offset_out(dst.first())), src.first()->as_XMMRegister());
   }
 }
 // A long move
 static void long_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
   // The only legal possibility for a long_move VMRegPair is:
   // 1: two stack slots (possibly unaligned)
   // as neither the java  or C calling convention will use registers
   // for longs.
   if (src.first()->is_stack() && dst.first()->is_stack()) {
     assert(src.second()->is_stack() && dst.second()->is_stack(), "must be all stack");
     __ movptr(rax, Address(rbp, reg2offset_in(src.first())));
     NOT_LP64(__ movptr(rbx, Address(rbp, reg2offset_in(src.second()))));
     __ movptr(Address(rsp, reg2offset_out(dst.first())), rax);
     NOT_LP64(__ movptr(Address(rsp, reg2offset_out(dst.second())), rbx));
   } else {
     ShouldNotReachHere();
   }
 }
 // A double move
 static void double_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
   // The only legal possibilities for a double_move VMRegPair are:
   // The painful thing here is that like long_move a VMRegPair might be
   // Because of the calling convention we know that src is either
   //   1: a single physical register (xmm registers only)
   //   2: two stack slots (possibly unaligned)
   // dst can only be a pair of stack slots.
   assert(dst.first()->is_stack() && (src.first()->is_XMMRegister() || src.first()->is_stack()), "bad args");
   if (src.first()->is_stack()) {
     // source is all stack
     __ movptr(rax, Address(rbp, reg2offset_in(src.first())));
     NOT_LP64(__ movptr(rbx, Address(rbp, reg2offset_in(src.second()))));
     __ movptr(Address(rsp, reg2offset_out(dst.first())), rax);
     NOT_LP64(__ movptr(Address(rsp, reg2offset_out(dst.second())), rbx));
   } else {
     // reg to stack
     // No worries about stack alignment
     __ movdbl(Address(rsp, reg2offset_out(dst.first())), src.first()->as_XMMRegister());
   }
 }
 void SharedRuntime::save_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {
   // We always ignore the frame_slots arg and just use the space just below frame pointer
   // which by this time is free to use
   switch (ret_type) {
   case T_FLOAT:
     __ fstp_s(Address(rbp, -wordSize));
     break;
   case T_DOUBLE:
     __ fstp_d(Address(rbp, -2*wordSize));
     break;
   case T_VOID:  break;
   case T_LONG:
     __ movptr(Address(rbp, -wordSize), rax);
     NOT_LP64(__ movptr(Address(rbp, -2*wordSize), rdx));
     break;
   default: {
     __ movptr(Address(rbp, -wordSize), rax);
     }
   }
 }
 void SharedRuntime::restore_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {
   // We always ignore the frame_slots arg and just use the space just below frame pointer
   // which by this time is free to use
   switch (ret_type) {
   case T_FLOAT:
     __ fld_s(Address(rbp, -wordSize));
     break;
   case T_DOUBLE:
     __ fld_d(Address(rbp, -2*wordSize));
     break;
   case T_LONG:
     __ movptr(rax, Address(rbp, -wordSize));
     NOT_LP64(__ movptr(rdx, Address(rbp, -2*wordSize)));
     break;
   case T_VOID:  break;
   default: {
     __ movptr(rax, Address(rbp, -wordSize));
     }
   }
 }
 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.
   int handle_index = 0;
   // Save down double word first
   for ( int i = 0; i < total_in_args; i++) {
     if (in_regs[i].first()->is_XMMRegister() && in_sig_bt[i] == T_DOUBLE) {
       int slot = handle_index * VMRegImpl::slots_per_word + arg_save_area;
       int offset = slot * VMRegImpl::stack_slot_size;
       handle_index += 2;
       assert(handle_index <= stack_slots, "overflow");
       if (map != NULL) {
         __ movdbl(Address(rsp, offset), in_regs[i].first()->as_XMMRegister());
       } else {
         __ movdbl(in_regs[i].first()->as_XMMRegister(), Address(rsp, offset));
       }
     }
     if (in_regs[i].first()->is_Register() && in_sig_bt[i] == T_LONG) {
       int slot = handle_index * VMRegImpl::slots_per_word + arg_save_area;
       int offset = slot * VMRegImpl::stack_slot_size;
       handle_index += 2;
       assert(handle_index <= stack_slots, "overflow");
       if (map != NULL) {
         __ movl(Address(rsp, offset), in_regs[i].first()->as_Register());
         if (in_regs[i].second()->is_Register()) {
           __ movl(Address(rsp, offset + 4), in_regs[i].second()->as_Register());
         }
       } else {
         __ movl(in_regs[i].first()->as_Register(), Address(rsp, offset));
         if (in_regs[i].second()->is_Register()) {
           __ movl(in_regs[i].second()->as_Register(), Address(rsp, offset + 4));
         }
       }
     }
   }
   // Save or restore single word registers
   for ( int i = 0; i < total_in_args; i++) {
     if (in_regs[i].first()->is_Register()) {
       int slot = handle_index++ * VMRegImpl::slots_per_word + arg_save_area;
       int offset = slot * VMRegImpl::stack_slot_size;
       assert(handle_index <= stack_slots, "overflow");
       if (in_sig_bt[i] == T_ARRAY && map != NULL) {
         map->set_oop(VMRegImpl::stack2reg(slot));;
       }
       // Value is in an input register pass we must flush it to the stack
       const Register reg = in_regs[i].first()->as_Register();
       switch (in_sig_bt[i]) {
         case T_ARRAY:
           if (map != NULL) {
             __ movptr(Address(rsp, offset), reg);
           } else {
             __ movptr(reg, Address(rsp, offset));
           }
           break;
         case T_BOOLEAN:
         case T_CHAR:
         case T_BYTE:
         case T_SHORT:
         case T_INT:
           if (map != NULL) {
             __ movl(Address(rsp, offset), reg);
           } else {
             __ movl(reg, Address(rsp, offset));
           }
           break;
         case T_OBJECT:
         default: ShouldNotReachHere();
       }
     } else if (in_regs[i].first()->is_XMMRegister()) {
       if (in_sig_bt[i] == T_FLOAT) {
         int slot = handle_index++ * VMRegImpl::slots_per_word + arg_save_area;
         int offset = slot * VMRegImpl::stack_slot_size;
         assert(handle_index <= stack_slots, "overflow");
         if (map != NULL) {
           __ movflt(Address(rsp, offset), in_regs[i].first()->as_XMMRegister());
         } else {
           __ movflt(in_regs[i].first()->as_XMMRegister(), Address(rsp, offset));
         }
       }
     } else if (in_regs[i].first()->is_stack()) {
       if (in_sig_bt[i] == T_ARRAY && map != NULL) {
         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));
       }
     }
   }
 }
 // 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,
                                                Register thread,
                                                int stack_slots,
                                                int total_c_args,
                                                int total_in_args,
                                                int arg_save_area,
                                                OopMapSet* oop_maps,
                                                VMRegPair* in_regs,
                                                BasicType* in_sig_bt) {
   __ block_comment("check GC_locker::needs_gc");
   Label cont;
   __ cmp8(ExternalAddress((address)GC_locker::needs_gc_address()), false);
   __ jcc(Assembler::equal, cont);
   // Save down any incoming oops 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);
   address the_pc = __ pc();
   oop_maps->add_gc_map( __ offset(), map);
   __ set_last_Java_frame(thread, rsp, noreg, the_pc);
   __ block_comment("block_for_jni_critical");
   __ push(thread);
   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::block_for_jni_critical)));
   __ increment(rsp, wordSize);
   __ get_thread(thread);
   __ reset_last_Java_frame(thread, false, true);
   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 - 1; i++) {
       if (in_regs[i].first()->is_Register()) {
         const Register reg = in_regs[i].first()->as_Register();
         __ xorptr(reg, reg);
       } else if (in_regs[i].first()->is_XMMRegister()) {
         __ xorpd(in_regs[i].first()->as_XMMRegister(), in_regs[i].first()->as_XMMRegister());
       } else if (in_regs[i].first()->is_FloatRegister()) {
         ShouldNotReachHere();
       } else if (in_regs[i].first()->is_stack()) {
         // Nothing to do
       } else {
         ShouldNotReachHere();
       }
       if (in_sig_bt[i] == T_LONG || in_sig_bt[i] == T_DOUBLE) {
         i++;
       }
     }
     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) {
   Register tmp_reg = rax;
   assert(!body_arg.first()->is_Register() || body_arg.first()->as_Register() != tmp_reg,
          "possible collision");
   assert(!length_arg.first()->is_Register() || length_arg.first()->as_Register() != tmp_reg,
          "possible collision");
   // Pass the length, ptr pair
   Label is_null, done;
   VMRegPair tmp(tmp_reg->as_VMReg());
   if (reg.first()->is_stack()) {
     // Load the arg up from the stack
     simple_move32(masm, reg, tmp);
     reg = tmp;
   }
   __ testptr(reg.first()->as_Register(), reg.first()->as_Register());
   __ jccb(Assembler::equal, is_null);
   __ lea(tmp_reg, Address(reg.first()->as_Register(), arrayOopDesc::base_offset_in_bytes(in_elem_type)));
   simple_move32(masm, tmp, body_arg);
   // load the length relative to the body.
   __ movl(tmp_reg, Address(tmp_reg, arrayOopDesc::length_offset_in_bytes() -
                            arrayOopDesc::base_offset_in_bytes(in_elem_type)));
   simple_move32(masm, tmp, length_arg);
   __ jmpb(done);
   __ bind(is_null);
   // Pass zeros
   __ xorptr(tmp_reg, tmp_reg);
   simple_move32(masm, tmp, body_arg);
   simple_move32(masm, tmp, length_arg);
   __ bind(done);
 }
 static void verify_oop_args(MacroAssembler* masm,
                             int total_args_passed,
                             const BasicType* sig_bt,
                             const VMRegPair* regs) {
   Register temp_reg = rbx;  // not part of any compiled calling seq
   if (VerifyOops) {
     for (int i = 0; i < total_args_passed; 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()) {
           __ movptr(temp_reg, Address(rsp, r->reg2stack() * VMRegImpl::stack_slot_size + wordSize));
           __ verify_oop(temp_reg);
         } else {
           __ verify_oop(r->as_Register());
         }
       }
     }
   }
 }
 static void gen_special_dispatch(MacroAssembler* masm,
                                  int total_args_passed,
                                  int comp_args_on_stack,
                                  vmIntrinsics::ID special_dispatch,
                                  const BasicType* sig_bt,
                                  const VMRegPair* regs) {
   verify_oop_args(masm, total_args_passed, sig_bt, regs);
   // 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(special_dispatch);
   if (ref_kind != 0) {
     member_arg_pos = total_args_passed - 1;  // trailing MemberName argument
     member_reg = rbx;  // known to be free at this point
     has_receiver = MethodHandles::ref_kind_has_receiver(ref_kind);
   } else if (special_dispatch == vmIntrinsics::_invokeBasic) {
     has_receiver = true;
   } else {
     guarantee(false, err_msg("special_dispatch=%d", special_dispatch));
   }
   if (member_reg != noreg) {
     // Load the member_arg into register, if necessary.
     assert(member_arg_pos >= 0 && member_arg_pos < total_args_passed, "oob");
     assert(sig_bt[member_arg_pos] == T_OBJECT, "dispatch argument must be an object");
     VMReg r = regs[member_arg_pos].first();
     assert(r->is_valid(), "bad member arg");
     if (r->is_stack()) {
       __ movptr(member_reg, Address(rsp, r->reg2stack() * VMRegImpl::stack_slot_size + wordSize));
     } else {
       // no data motion is needed
       member_reg = r->as_Register();
     }
   }
   if (has_receiver) {
     // Make sure the receiver is loaded into a register.
     assert(total_args_passed > 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.
       assert(false, "receiver always in a register");
       receiver_reg = rcx;  // known to be free at this point
       __ movptr(receiver_reg, Address(rsp, r->reg2stack() * VMRegImpl::stack_slot_size + wordSize));
     } 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, special_dispatch,
                                                  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,
                                                 int total_in_args,
                                                 int comp_args_on_stack,
                                                 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,
                          total_in_args,
                          comp_args_on_stack,
                          method->intrinsic_id(),
                          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");
   // An OopMap for lock (and class if static)
   OopMapSet *oop_maps = new OopMapSet();
   // 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)
   int total_c_args = total_in_args;
   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) {
         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.
   int out_arg_slots;
   out_arg_slots = c_calling_convention(out_sig_bt, out_regs, total_c_args);
   // Compute framesize for the wrapper.  We need to handlize all oops in
   // registers a max of 2 on x86.
   // 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 total_save_slots = 2 * VMRegImpl::slots_per_word; // 2 arguments passed in registers
   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:  // critical array (uses 2 slots on LP64)
           case T_BOOLEAN:
           case T_BYTE:
           case T_SHORT:
           case T_CHAR:
           case T_INT:  single_slots++; break;
           case T_LONG: double_slots++; break;
           default:  ShouldNotReachHere();
         }
       } else if (in_regs[i].first()->is_XMMRegister()) {
         switch (in_sig_bt[i]) {
           case T_FLOAT:  single_slots++; break;
           case T_DOUBLE: double_slots++; break;
           default:  ShouldNotReachHere();
         }
       } else if (in_regs[i].first()->is_FloatRegister()) {
         ShouldNotReachHere();
       }
     }
     total_save_slots = double_slots * 2 + single_slots;
     // align the save area
     if (double_slots != 0) {
       stack_slots = round_to(stack_slots, 2);
     }
   }
   int oop_handle_offset = stack_slots;
   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 (+2) to save return values or temp during shuffling
   // + 2 for return address (which we own) and saved rbp,
   stack_slots += 4;
   // Ok The space we have allocated will look like:
   //
   //
   // FP-> |                     |
   //      |---------------------|
   //      | 2 slots for moves   |
   //      |---------------------|
   //      | lock box (if sync)  |
   //      |---------------------| <- lock_slot_offset  (-lock_slot_rbp_offset)
   //      | klass (if static)   |
   //      |---------------------| <- klass_slot_offset
   //      | oopHandle area      |
   //      |---------------------| <- oop_handle_offset (a max of 2 registers)
   //      | outbound memory     |
   //      | based arguments     |
   //      |                     |
   //      |---------------------|
   //      |                     |
   // SP-> | out_preserved_slots |
   //
   //
   // ****************************************************************************
   // WARNING - on Windows Java Natives use pascal calling convention and pop the
   // arguments off of the stack after the jni call. Before the call we can use
   // instructions that are SP relative. After the jni call we switch to FP
   // relative instructions instead of re-adjusting the stack on windows.
   // ****************************************************************************
   // Now compute actual number of stack words we need rounding to make
   // stack properly aligned.
   stack_slots = round_to(stack_slots, StackAlignmentInSlots);
   int stack_size = stack_slots * VMRegImpl::stack_slot_size;
   intptr_t start = (intptr_t)__ pc();
   // First thing make an ic check to see if we should even be here
   // We are free to use all registers as temps without saving them and
   // restoring them except rbp. rbp is the only callee save register
   // as far as the interpreter and the compiler(s) are concerned.
   const Register ic_reg = rax;
   const Register receiver = rcx;
   Label hit;
   Label exception_pending;
   __ verify_oop(receiver);
   __ cmpptr(ic_reg, Address(receiver, oopDesc::klass_offset_in_bytes()));
   __ jcc(Assembler::equal, hit);
   __ jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
   // verified entry must be aligned for code patching.
   // and the first 5 bytes must be in the same cache line
   // if we align at 8 then we will be sure 5 bytes are in the same line
   __ align(8);
   __ bind(hit);
   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 = rcx;
     Register result = rax;
     __ movptr(result, Address(receiver, oopDesc::mark_offset_in_bytes()));
     // check if locked
     __ testptr(result, markOopDesc::unlocked_value);
     __ jcc (Assembler::zero, slowCase);
     if (UseBiasedLocking) {
       // Check if biased and fall through to runtime if so
       __ testptr(result, markOopDesc::biased_lock_bit_in_place);
       __ jcc (Assembler::notZero, slowCase);
     }
     // get hash
     __ andptr(result, markOopDesc::hash_mask_in_place);
     // test if hashCode exists
     __ jcc  (Assembler::zero, slowCase);
     __ shrptr(result, markOopDesc::hash_shift);
     __ ret(0);
     __ bind (slowCase);
   }
 #endif // COMPILER1
   // The instruction at the verified entry point must be 5 bytes or longer
   // because it can be patched on the fly by make_non_entrant. The stack bang
   // instruction fits that requirement.
   // Generate stack overflow check
   if (UseStackBanging) {
     __ bang_stack_with_offset(StackShadowPages*os::vm_page_size());
   } else {
     // need a 5 byte instruction to allow MT safe patching to non-entrant
     __ fat_nop();
   }
   // Generate a new frame for the wrapper.
   __ enter();
   // -2 because return address is already present and so is saved rbp
   __ subptr(rsp, stack_size - 2*wordSize);
   // Frame is now completed as far as size and linkage.
   int frame_complete = ((intptr_t)__ pc()) - start;
   // Calculate the difference between rsp and rbp,. We need to know it
   // after the native call because on windows Java Natives will pop
   // the arguments and it is painful to do rsp relative addressing
   // in a platform independent way. So after the call we switch to
   // rbp, relative addressing.
   int fp_adjustment = stack_size - 2*wordSize;
 #ifdef COMPILER2
   // C2 may leave the stack dirty if not in SSE2+ mode
   if (UseSSE >= 2) {
     __ verify_FPU(0, "c2i transition should have clean FPU stack");
   } else {
     __ empty_FPU_stack();
   }
 #endif /* COMPILER2 */
   // Compute the rbp, offset for any slots used after the jni call
   int lock_slot_rbp_offset = (lock_slot_offset*VMRegImpl::stack_slot_size) - fp_adjustment;
   // We use rdi as a thread pointer because it is callee save and
   // if we load it once it is usable thru the entire wrapper
   const Register thread = rdi;
   // We use rsi as the oop handle for the receiver/klass
   // It is callee save so it survives the call to native
   const Register oop_handle_reg = rsi;
   __ get_thread(thread);
   if (is_critical_native) {
     check_needs_gc_for_critical_native(masm, thread, stack_slots, total_c_args, 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*
   // and, if static, the class mirror instead of a receiver.  This pretty much
   // guarantees that register layout will not match (and x86 doesn't use reg
   // parms though amd does).  Since the native abi doesn't use register args
   // and the java conventions does we don't have to worry about collisions.
   // All of our moved are reg->stack or stack->stack.
   // We ignore the extra arguments during the shuffle and handle them at the
   // last moment. 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.
   int c_arg = is_critical_native ? 0 : (method->is_static() ? 2 : 1 );
   // Record rsp-based slot for receiver on stack for non-static methods
   int receiver_offset = -1;
   // 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*/);
   // Mark location of rbp,
   // map->set_callee_saved(VMRegImpl::stack2reg( stack_slots - 2), stack_slots * 2, 0, rbp->as_VMReg());
   // We know that we only have args in at most two integer registers (rcx, rdx). So rax, rbx
   // Are free to temporaries if we have to do  stack to steck moves.
   // All inbound args are referenced based on rbp, and all outbound args via rsp.
   for (int i = 0; i < total_in_args ; i++, c_arg++ ) {
     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 + 1], out_regs[c_arg]);
           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:
         simple_move32(masm, in_regs[i], out_regs[c_arg]);
     }
   }
   // Pre-load a static method's oop into rsi.  Used both by locking code and
   // the normal JNI call code.
   if (method->is_static() && !is_critical_native) {
     //  load opp into a register
     __ movoop(oop_handle_reg, JNIHandles::make_local(Klass::cast(method->method_holder())->java_mirror()));
     // Now handlize the static class mirror it's known not-null.
     __ movptr(Address(rsp, klass_offset), oop_handle_reg);
     map->set_oop(VMRegImpl::stack2reg(klass_slot_offset));
     // Now get the handle
     __ lea(oop_handle_reg, Address(rsp, klass_offset));
     // store the klass handle as second argument
     __ movptr(Address(rsp, wordSize), oop_handle_reg);
   }
   // Change state to native (we save the return address in the thread, since it might not
   // be pushed on the stack when we do a a stack traversal). It is enough that the pc()
   // points into the right code segment. It does not have to be the correct return pc.
   // We use the same pc/oopMap repeatedly when we call out
   intptr_t the_pc = (intptr_t) __ pc();
   oop_maps->add_gc_map(the_pc - start, map);
   __ set_last_Java_frame(thread, rsp, noreg, (address)the_pc);
   // We have all of the arguments setup at this point. We must not touch any register
   // argument registers at this point (what if we save/restore them there are no oop?
   {
     SkipIfEqual skip_if(masm, &DTraceMethodProbes, 0);
     __ mov_metadata(rax, method());
     __ call_VM_leaf(
          CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_entry),
          thread, rax);
   }
   // RedefineClasses() tracing support for obsolete method entry
   if (RC_TRACE_IN_RANGE(0x00001000, 0x00002000)) {
     __ mov_metadata(rax, method());
     __ call_VM_leaf(
          CAST_FROM_FN_PTR(address, SharedRuntime::rc_trace_method_entry),
          thread, rax);
   }
   // These are register definitions we need for locking/unlocking
   const Register swap_reg = rax;  // Must use rax, for cmpxchg instruction
   const Register obj_reg  = rcx;  // Will contain the oop
   const Register lock_reg = rdx;  // Address of compiler lock object (BasicLock)
   Label slow_path_lock;
   Label lock_done;
   // Lock a synchronized method
   if (method->is_synchronized()) {
     assert(!is_critical_native, "unhandled");
     const int mark_word_offset = BasicLock::displaced_header_offset_in_bytes();
     // Get the handle (the 2nd argument)
     __ movptr(oop_handle_reg, Address(rsp, wordSize));
     // Get address of the box
     __ lea(lock_reg, Address(rbp, lock_slot_rbp_offset));
     // Load the oop from the handle
     __ movptr(obj_reg, Address(oop_handle_reg, 0));
     if (UseBiasedLocking) {
       // Note that oop_handle_reg is trashed during this call
       __ biased_locking_enter(lock_reg, obj_reg, swap_reg, oop_handle_reg, false, lock_done, &slow_path_lock);
     }
     // Load immediate 1 into swap_reg %rax,
     __ movptr(swap_reg, 1);
     // Load (object->mark() | 1) into swap_reg %rax,
     __ orptr(swap_reg, Address(obj_reg, 0));
     // Save (object->mark() | 1) into BasicLock's displaced header
     __ movptr(Address(lock_reg, mark_word_offset), swap_reg);
     if (os::is_MP()) {
       __ lock();
     }
     // src -> dest iff dest == rax, else rax, <- dest
     // *obj_reg = lock_reg iff *obj_reg == rax, else rax, = *(obj_reg)
     __ cmpxchgptr(lock_reg, Address(obj_reg, 0));
     __ jcc(Assembler::equal, lock_done);
     // Test if the oopMark is an obvious stack pointer, i.e.,
     //  1) (mark & 3) == 0, and
     //  2) rsp <= mark < mark + os::pagesize()
     // These 3 tests can be done by evaluating the following
     // expression: ((mark - rsp) & (3 - os::vm_page_size())),
     // assuming both stack pointer and pagesize have their
     // least significant 2 bits clear.
     // NOTE: the oopMark is in swap_reg %rax, as the result of cmpxchg
     __ subptr(swap_reg, rsp);
     __ andptr(swap_reg, 3 - os::vm_page_size());
     // Save the test result, for recursive case, the result is zero
     __ movptr(Address(lock_reg, mark_word_offset), swap_reg);
     __ jcc(Assembler::notEqual, slow_path_lock);
     // Slow path will re-enter here
     __ bind(lock_done);
     if (UseBiasedLocking) {
       // Re-fetch oop_handle_reg as we trashed it above
       __ movptr(oop_handle_reg, Address(rsp, wordSize));
     }
   }
   // Finally just about ready to make the JNI call
   // get JNIEnv* which is first argument to native
   if (!is_critical_native) {
     __ lea(rdx, Address(thread, in_bytes(JavaThread::jni_environment_offset())));
     __ movptr(Address(rsp, 0), rdx);
   }
   // Now set thread in native
   __ movl(Address(thread, JavaThread::thread_state_offset()), _thread_in_native);
   __ call(RuntimeAddress(native_func));
   // WARNING - on Windows Java Natives use pascal calling convention and pop the
   // arguments off of the stack. We could just re-adjust the stack pointer here
   // and continue to do SP relative addressing but we instead switch to FP
   // relative addressing.
   // Unpack native results.
   switch (ret_type) {
   case T_BOOLEAN: __ c2bool(rax);            break;
   case T_CHAR   : __ andptr(rax, 0xFFFF);    break;
   case T_BYTE   : __ sign_extend_byte (rax); break;
   case T_SHORT  : __ sign_extend_short(rax); break;
   case T_INT    : /* nothing to do */        break;
   case T_DOUBLE :
   case T_FLOAT  :
     // Result is in st0 we'll save as needed
     break;
   case T_ARRAY:                 // Really a handle
   case T_OBJECT:                // Really a handle
       break; // can't de-handlize until after safepoint check
   case T_VOID: break;
   case T_LONG: break;
   default       : ShouldNotReachHere();
   }
   // 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.
   __ movl(Address(thread, JavaThread::thread_state_offset()), _thread_in_native_trans);
   if(os::is_MP()) {
     if (UseMembar) {
       // Force this write out before the read below
       __ membar(Assembler::Membar_mask_bits(
            Assembler::LoadLoad | Assembler::LoadStore |
            Assembler::StoreLoad | Assembler::StoreStore));
     } 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(thread, rcx);
     }
   }
   if (AlwaysRestoreFPU) {
     // Make sure the control word is correct.
     __ fldcw(ExternalAddress(StubRoutines::addr_fpu_cntrl_wrd_std()));
   }
   Label after_transition;
   // check for safepoint operation in progress and/or pending suspend requests
   { Label Continue;
     __ cmp32(ExternalAddress((address)SafepointSynchronize::address_of_state()),
              SafepointSynchronize::_not_synchronized);
     Label L;
     __ jcc(Assembler::notEqual, L);
     __ cmpl(Address(thread, JavaThread::suspend_flags_offset()), 0);
     __ jcc(Assembler::equal, Continue);
     __ bind(L);
     // Don't use call_VM as it will see a possible pending exception and forward it
     // and never return here preventing us from clearing _last_native_pc down below.
     // Also can't use call_VM_leaf either as it will check to see if rsi & rdi are
     // preserved and correspond to the bcp/locals pointers. So we do a runtime call
     // by hand.
     //
     save_native_result(masm, ret_type, stack_slots);
     __ push(thread);
     if (!is_critical_native) {
       __ call(RuntimeAddress(CAST_FROM_FN_PTR(address,
                                               JavaThread::check_special_condition_for_native_trans)));
     } else {
       __ call(RuntimeAddress(CAST_FROM_FN_PTR(address,
                                               JavaThread::check_special_condition_for_native_trans_and_transition)));
     }
     __ increment(rsp, wordSize);
     // 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.
       __ jmpb(after_transition);
     }
     __ bind(Continue);
   }
   // change thread state
   __ movl(Address(thread, JavaThread::thread_state_offset()), _thread_in_Java);
   __ bind(after_transition);
   Label reguard;
   Label reguard_done;
   __ cmpl(Address(thread, JavaThread::stack_guard_state_offset()), JavaThread::stack_guard_yellow_disabled);
   __ jcc(Assembler::equal, reguard);
   // slow path reguard  re-enters here
   __ bind(reguard_done);
   // Handle possible exception (will unlock if necessary)
   // native result if any is live
   // Unlock
   Label slow_path_unlock;
   Label unlock_done;
   if (method->is_synchronized()) {
     Label done;
     // Get locked oop from the handle we passed to jni
     __ movptr(obj_reg, Address(oop_handle_reg, 0));
     if (UseBiasedLocking) {
       __ biased_locking_exit(obj_reg, rbx, done);
     }
     // Simple recursive lock?
     __ cmpptr(Address(rbp, lock_slot_rbp_offset), (int32_t)NULL_WORD);
     __ jcc(Assembler::equal, done);
     // Must save rax, if if it is live now because cmpxchg must use it
     if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
       save_native_result(masm, ret_type, stack_slots);
     }
     //  get old displaced header
     __ movptr(rbx, Address(rbp, lock_slot_rbp_offset));
     // get address of the stack lock
     __ lea(rax, Address(rbp, lock_slot_rbp_offset));
     // Atomic swap old header if oop still contains the stack lock
     if (os::is_MP()) {
     __ lock();
     }
     // src -> dest iff dest == rax, else rax, <- dest
     // *obj_reg = rbx, iff *obj_reg == rax, else rax, = *(obj_reg)
     __ cmpxchgptr(rbx, Address(obj_reg, 0));
     __ jcc(Assembler::notEqual, slow_path_unlock);
     // slow path re-enters here
     __ bind(unlock_done);
     if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
       restore_native_result(masm, ret_type, stack_slots);
     }
     __ bind(done);
   }
   {
     SkipIfEqual skip_if(masm, &DTraceMethodProbes, 0);
     // Tell dtrace about this method exit
     save_native_result(masm, ret_type, stack_slots);
     __ mov_metadata(rax, method());
     __ call_VM_leaf(
          CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_exit),
          thread, rax);
     restore_native_result(masm, ret_type, stack_slots);
   }
   // We can finally stop using that last_Java_frame we setup ages ago
   __ reset_last_Java_frame(thread, false, true);
   // Unpack oop result
   if (ret_type == T_OBJECT || ret_type == T_ARRAY) {
       Label L;
       __ cmpptr(rax, (int32_t)NULL_WORD);
       __ jcc(Assembler::equal, L);
       __ movptr(rax, Address(rax, 0));
       __ bind(L);
       __ verify_oop(rax);
   }
   if (!is_critical_native) {
     // reset handle block
     __ movptr(rcx, Address(thread, JavaThread::active_handles_offset()));
     __ movptr(Address(rcx, JNIHandleBlock::top_offset_in_bytes()), NULL_WORD);
     // Any exception pending?
     __ cmpptr(Address(thread, in_bytes(Thread::pending_exception_offset())), (int32_t)NULL_WORD);
     __ jcc(Assembler::notEqual, exception_pending);
   }
   // no exception, we're almost done
   // check that only result value is on FPU stack
   __ verify_FPU(ret_type == T_FLOAT || ret_type == T_DOUBLE ? 1 : 0, "native_wrapper normal exit");
   // Fixup floating pointer results so that result looks like a return from a compiled method
   if (ret_type == T_FLOAT) {
     if (UseSSE >= 1) {
       // Pop st0 and store as float and reload into xmm register
       __ fstp_s(Address(rbp, -4));
       __ movflt(xmm0, Address(rbp, -4));
     }
   } else if (ret_type == T_DOUBLE) {
     if (UseSSE >= 2) {
       // Pop st0 and store as double and reload into xmm register
       __ fstp_d(Address(rbp, -8));
       __ movdbl(xmm0, Address(rbp, -8));
     }
   }
   // Return
   __ leave();
   __ ret(0);
   // Unexpected paths are out of line and go here
   // Slow path locking & unlocking
   if (method->is_synchronized()) {
     // BEGIN Slow path lock
     __ bind(slow_path_lock);
     // has last_Java_frame setup. No exceptions so do vanilla call not call_VM
     // args are (oop obj, BasicLock* lock, JavaThread* thread)
     __ push(thread);
     __ push(lock_reg);
     __ push(obj_reg);
     __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_locking_C)));
     __ addptr(rsp, 3*wordSize);
 #ifdef ASSERT
     { Label L;
     __ cmpptr(Address(thread, in_bytes(Thread::pending_exception_offset())), (int)NULL_WORD);
     __ jcc(Assembler::equal, L);
     __ stop("no pending exception allowed on exit from monitorenter");
     __ bind(L);
     }
 #endif
     __ jmp(lock_done);
     // END Slow path lock
     // BEGIN Slow path unlock
     __ bind(slow_path_unlock);
     // Slow path unlock
     if (ret_type == T_FLOAT || ret_type == T_DOUBLE ) {
       save_native_result(masm, ret_type, stack_slots);
     }
     // Save pending exception around call to VM (which contains an EXCEPTION_MARK)
     __ pushptr(Address(thread, in_bytes(Thread::pending_exception_offset())));
     __ movptr(Address(thread, in_bytes(Thread::pending_exception_offset())), NULL_WORD);
     // should be a peal
     // +wordSize because of the push above
     __ lea(rax, Address(rbp, lock_slot_rbp_offset));
     __ push(rax);
     __ push(obj_reg);
     __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C)));
     __ addptr(rsp, 2*wordSize);
 #ifdef ASSERT
     {
       Label L;
       __ cmpptr(Address(thread, in_bytes(Thread::pending_exception_offset())), (int32_t)NULL_WORD);
       __ jcc(Assembler::equal, L);
       __ stop("no pending exception allowed on exit complete_monitor_unlocking_C");
       __ bind(L);
     }
 #endif /* ASSERT */
     __ popptr(Address(thread, in_bytes(Thread::pending_exception_offset())));
     if (ret_type == T_FLOAT || ret_type == T_DOUBLE ) {
       restore_native_result(masm, ret_type, stack_slots);
     }
     __ jmp(unlock_done);
     // END Slow path unlock
   }
   // SLOW PATH Reguard the stack if needed
   __ bind(reguard);
   save_native_result(masm, ret_type, stack_slots);
   {
     __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::reguard_yellow_pages)));
   }
   restore_native_result(masm, ret_type, stack_slots);
   __ jmp(reguard_done);
   // BEGIN EXCEPTION PROCESSING
   if (!is_critical_native) {
     // Forward  the exception
     __ bind(exception_pending);
     // remove possible return value from FPU register stack
     __ empty_FPU_stack();
     // pop our frame
     __ leave();
     // and forward the exception
     __ jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
   }
   __ flush();
   nmethod *nm = nmethod::new_native_nmethod(method,
                                             compile_id,
                                             masm->code(),
                                             vep_offset,
                                             frame_complete,
                                             stack_slots / VMRegImpl::slots_per_word,
                                             (is_static ? in_ByteSize(klass_offset) : in_ByteSize(receiver_offset)),
                                             in_ByteSize(lock_slot_offset*VMRegImpl::stack_slot_size),
                                             oop_maps);
   if (is_critical_native) {
     nm->set_lazy_critical_native(true);
   }
   return nm;
 }
 #ifdef HAVE_DTRACE_H
 // ---------------------------------------------------------------------------
 // Generate a dtrace nmethod for a given signature.  The method takes arguments
 // in the Java compiled code convention, marshals them to the native
 // abi and then leaves nops at the position you would expect to call a native
 // function. When the probe is enabled the nops are replaced with a trap
 // instruction that dtrace inserts and the trace will cause a notification
 // to dtrace.
 //
 // The probes are only able to take primitive types and java/lang/String as
 // arguments.  No other java types are allowed. Strings are converted to utf8
 // strings so that from dtrace point of view java strings are converted to C
 // strings. There is an arbitrary fixed limit on the total space that a method
 // can use for converting the strings. (256 chars per string in the signature).
 // So any java string larger then this is truncated.
 nmethod *SharedRuntime::generate_dtrace_nmethod(
     MacroAssembler *masm, methodHandle method) {
   // generate_dtrace_nmethod is guarded by a mutex so we are sure to
   // be single threaded in this method.
   assert(AdapterHandlerLibrary_lock->owned_by_self(), "must be");
   // Fill in the signature array, for the calling-convention call.
   int total_args_passed = method->size_of_parameters();
   BasicType* in_sig_bt  = NEW_RESOURCE_ARRAY(BasicType, total_args_passed);
   VMRegPair  *in_regs   = NEW_RESOURCE_ARRAY(VMRegPair, total_args_passed);
   // The signature we are going to use for the trap that dtrace will see
   // java/lang/String is converted. We drop "this" and any other object
   // is converted to NULL.  (A one-slot java/lang/Long object reference
   // is converted to a two-slot long, which is why we double the allocation).
   BasicType* out_sig_bt = NEW_RESOURCE_ARRAY(BasicType, total_args_passed * 2);
   VMRegPair* out_regs   = NEW_RESOURCE_ARRAY(VMRegPair, total_args_passed * 2);
   int i=0;
   int total_strings = 0;
   int first_arg_to_pass = 0;
   int total_c_args = 0;
   if( !method->is_static() ) {  // Pass in receiver first
     in_sig_bt[i++] = T_OBJECT;
     first_arg_to_pass = 1;
   }
   // We need to convert the java args to where a native (non-jni) function
   // would expect them. To figure out where they go we convert the java
   // signature to a C signature.
   SignatureStream ss(method->signature());
   for ( ; !ss.at_return_type(); ss.next()) {
     BasicType bt = ss.type();
     in_sig_bt[i++] = bt;  // Collect remaining bits of signature
     out_sig_bt[total_c_args++] = bt;
     if( bt == T_OBJECT) {
       Symbol* s = ss.as_symbol_or_null();   // symbol is created
       if (s == vmSymbols::java_lang_String()) {
         total_strings++;
         out_sig_bt[total_c_args-1] = T_ADDRESS;
       } else if (s == vmSymbols::java_lang_Boolean() ||
                  s == vmSymbols::java_lang_Character() ||
                  s == vmSymbols::java_lang_Byte() ||
                  s == vmSymbols::java_lang_Short() ||
                  s == vmSymbols::java_lang_Integer() ||
                  s == vmSymbols::java_lang_Float()) {
         out_sig_bt[total_c_args-1] = T_INT;
       } else if (s == vmSymbols::java_lang_Long() ||
                  s == vmSymbols::java_lang_Double()) {
         out_sig_bt[total_c_args-1] = T_LONG;
         out_sig_bt[total_c_args++] = T_VOID;
       }
     } else if ( bt == T_LONG || bt == T_DOUBLE ) {
       in_sig_bt[i++] = T_VOID;   // Longs & doubles take 2 Java slots
       out_sig_bt[total_c_args++] = T_VOID;
     }
   }
   assert(i==total_args_passed, "validly parsed signature");
   // Now get the compiled-Java layout as input arguments
   int comp_args_on_stack;
   comp_args_on_stack = SharedRuntime::java_calling_convention(
       in_sig_bt, in_regs, total_args_passed, false);
   // Now figure out where the args must be stored and how much stack space
   // they require (neglecting out_preserve_stack_slots).
   int out_arg_slots;
   out_arg_slots = c_calling_convention(out_sig_bt, out_regs, total_c_args);
   // 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 space for the string(s) we must convert
   int* string_locs   = NEW_RESOURCE_ARRAY(int, total_strings + 1);
   for (i = 0; i < total_strings ; i++) {
     string_locs[i] = stack_slots;
     stack_slots += max_dtrace_string_size / VMRegImpl::stack_slot_size;
   }
   // + 2 for return address (which we own) and saved rbp,
   stack_slots += 2;
   // Ok The space we have allocated will look like:
   //
   //
   // FP-> |                     |
   //      |---------------------|
   //      | string[n]           |
   //      |---------------------| <- string_locs[n]
   //      | string[n-1]         |
   //      |---------------------| <- string_locs[n-1]
   //      | ...                 |
   //      | ...                 |
   //      |---------------------| <- string_locs[1]
   //      | string[0]           |
   //      |---------------------| <- string_locs[0]
   //      | outbound memory     |
   //      | based arguments     |
   //      |                     |
   //      |---------------------|
   //      |                     |
   // 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;
   intptr_t start = (intptr_t)__ pc();
   // First thing make an ic check to see if we should even be here
   // We are free to use all registers as temps without saving them and
   // restoring them except rbp. rbp, is the only callee save register
   // as far as the interpreter and the compiler(s) are concerned.
   const Register ic_reg = rax;
   const Register receiver = rcx;
   Label hit;
   Label exception_pending;
   __ verify_oop(receiver);
   __ cmpl(ic_reg, Address(receiver, oopDesc::klass_offset_in_bytes()));
   __ jcc(Assembler::equal, hit);
   __ jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
   // verified entry must be aligned for code patching.
   // and the first 5 bytes must be in the same cache line
   // if we align at 8 then we will be sure 5 bytes are in the same line
   __ align(8);
   __ bind(hit);
   int vep_offset = ((intptr_t)__ pc()) - start;
   // The instruction at the verified entry point must be 5 bytes or longer
   // because it can be patched on the fly by make_non_entrant. The stack bang
   // instruction fits that requirement.
   // Generate stack overflow check
   if (UseStackBanging) {
     if (stack_size <= StackShadowPages*os::vm_page_size()) {
       __ bang_stack_with_offset(StackShadowPages*os::vm_page_size());
     } else {
       __ movl(rax, stack_size);
       __ bang_stack_size(rax, rbx);
     }
   } else {
     // need a 5 byte instruction to allow MT safe patching to non-entrant
     __ fat_nop();
   }
   assert(((int)__ pc() - start - vep_offset) >= 5,
          "valid size for make_non_entrant");
   // Generate a new frame for the wrapper.
   __ enter();
   // -2 because return address is already present and so is saved rbp,
   if (stack_size - 2*wordSize != 0) {
     __ subl(rsp, stack_size - 2*wordSize);
   }
   // Frame is now completed as far a size and linkage.
   int frame_complete = ((intptr_t)__ pc()) - start;
   // First thing we do store all the args as if we are doing the call.
   // Since the C calling convention is stack based that ensures that
   // all the Java register args are stored before we need to convert any
   // string we might have.
   int sid = 0;
   int c_arg, j_arg;
   int string_reg = 0;
   for (j_arg = first_arg_to_pass, c_arg = 0 ;
        j_arg < total_args_passed ; j_arg++, c_arg++ ) {
     VMRegPair src = in_regs[j_arg];
     VMRegPair dst = out_regs[c_arg];
     assert(dst.first()->is_stack() || in_sig_bt[j_arg] == T_VOID,
            "stack based abi assumed");
     switch (in_sig_bt[j_arg]) {
       case T_ARRAY:
       case T_OBJECT:
         if (out_sig_bt[c_arg] == T_ADDRESS) {
           // Any register based arg for a java string after the first
           // will be destroyed by the call to get_utf so we store
           // the original value in the location the utf string address
           // will eventually be stored.
           if (src.first()->is_reg()) {
             if (string_reg++ != 0) {
               simple_move32(masm, src, dst);
             }
           }
         } else if (out_sig_bt[c_arg] == T_INT || out_sig_bt[c_arg] == T_LONG) {
           // need to unbox a one-word value
           Register in_reg = rax;
           if ( src.first()->is_reg() ) {
             in_reg = src.first()->as_Register();
           } else {
             simple_move32(masm, src, in_reg->as_VMReg());
           }
           Label skipUnbox;
           __ movl(Address(rsp, reg2offset_out(dst.first())), NULL_WORD);
           if ( out_sig_bt[c_arg] == T_LONG ) {
             __ movl(Address(rsp, reg2offset_out(dst.second())), NULL_WORD);
           }
           __ testl(in_reg, in_reg);
           __ jcc(Assembler::zero, skipUnbox);
           assert(dst.first()->is_stack() &&
                  (!dst.second()->is_valid() || dst.second()->is_stack()),
                  "value(s) must go into stack slots");
           BasicType bt = out_sig_bt[c_arg];
           int box_offset = java_lang_boxing_object::value_offset_in_bytes(bt);
           if ( bt == T_LONG ) {
             __ movl(rbx, Address(in_reg,
                                  box_offset + VMRegImpl::stack_slot_size));
             __ movl(Address(rsp, reg2offset_out(dst.second())), rbx);
           }
           __ movl(in_reg,  Address(in_reg, box_offset));
           __ movl(Address(rsp, reg2offset_out(dst.first())), in_reg);
           __ bind(skipUnbox);
         } else {
           // Convert the arg to NULL
           __ movl(Address(rsp, reg2offset_out(dst.first())), NULL_WORD);
         }
         if (out_sig_bt[c_arg] == T_LONG) {
           assert(out_sig_bt[c_arg+1] == T_VOID, "must be");
           ++c_arg; // Move over the T_VOID To keep the loop indices in sync
         }
         break;
       case T_VOID:
         break;
       case T_FLOAT:
         float_move(masm, src, dst);
         break;
       case T_DOUBLE:
         assert( j_arg + 1 < total_args_passed &&
                 in_sig_bt[j_arg + 1] == T_VOID, "bad arg list");
         double_move(masm, src, dst);
         break;
       case T_LONG :
         long_move(masm, src, dst);
         break;
       case T_ADDRESS: assert(false, "found T_ADDRESS in java args");
       default:
         simple_move32(masm, src, dst);
     }
   }
   // Now we must convert any string we have to utf8
   //
   for (sid = 0, j_arg = first_arg_to_pass, c_arg = 0 ;
        sid < total_strings ; j_arg++, c_arg++ ) {
     if (out_sig_bt[c_arg] == T_ADDRESS) {
       Address utf8_addr = Address(
           rsp, string_locs[sid++] * VMRegImpl::stack_slot_size);
       __ leal(rax, utf8_addr);
       // The first string we find might still be in the original java arg
       // register
       VMReg orig_loc = in_regs[j_arg].first();
       Register string_oop;
       // This is where the argument will eventually reside
       Address dest = Address(rsp, reg2offset_out(out_regs[c_arg].first()));
       if (sid == 1 && orig_loc->is_reg()) {
         string_oop = orig_loc->as_Register();
         assert(string_oop != rax, "smashed arg");
       } else {
         if (orig_loc->is_reg()) {
           // Get the copy of the jls object
           __ movl(rcx, dest);
         } else {
           // arg is still in the original location
           __ movl(rcx, Address(rbp, reg2offset_in(orig_loc)));
         }
         string_oop = rcx;
       }
       Label nullString;
       __ movl(dest, NULL_WORD);
       __ testl(string_oop, string_oop);
       __ jcc(Assembler::zero, nullString);
       // Now we can store the address of the utf string as the argument
       __ movl(dest, rax);
       // And do the conversion
       __ call_VM_leaf(CAST_FROM_FN_PTR(
              address, SharedRuntime::get_utf), string_oop, rax);
       __ bind(nullString);
     }
     if (in_sig_bt[j_arg] == T_OBJECT && out_sig_bt[c_arg] == T_LONG) {
       assert(out_sig_bt[c_arg+1] == T_VOID, "must be");
       ++c_arg; // Move over the T_VOID To keep the loop indices in sync
     }
   }
   // Ok now we are done. Need to place the nop that dtrace wants in order to
   // patch in the trap
   int patch_offset = ((intptr_t)__ pc()) - start;
   __ nop();
   // Return
   __ leave();
   __ ret(0);
   __ flush();
   nmethod *nm = nmethod::new_dtrace_nmethod(
       method, masm->code(), vep_offset, patch_offset, frame_complete,
       stack_slots / VMRegImpl::slots_per_word);
   return nm;
 }
 #endif // HAVE_DTRACE_H
 // this function returns the adjust size (in number of words) to a c2i adapter
 // activation for use during deoptimization
 int Deoptimization::last_frame_adjust(int callee_parameters, int callee_locals ) {
   return (callee_locals - callee_parameters) * Interpreter::stackElementWords;
 }
 uint SharedRuntime::out_preserve_stack_slots() {
   return 0;
 }
 //------------------------------generate_deopt_blob----------------------------
 void SharedRuntime::generate_deopt_blob() {
   // allocate space for the code
   ResourceMark rm;
   // setup code generation tools
   CodeBuffer   buffer("deopt_blob", 1024, 1024);
   MacroAssembler* masm = new MacroAssembler(&buffer);
   int frame_size_in_words;
   OopMap* map = NULL;
   // Account for the extra args we place on the stack
   // by the time we call fetch_unroll_info
   const int additional_words = 2; // deopt kind, thread
   OopMapSet *oop_maps = new OopMapSet();
   // -------------
   // This code enters when returning to a de-optimized nmethod.  A return
   // address has been pushed on the the stack, and return values are in
   // registers.
   // If we are doing a normal deopt then we were called from the patched
   // nmethod from the point we returned to the nmethod. So the return
   // address on the stack is wrong by NativeCall::instruction_size
   // We will adjust the value to it looks like we have the original return
   // address on the stack (like when we eagerly deoptimized).
   // In the case of an exception pending with deoptimized then we enter
   // with a return address on the stack that points after the call we patched
   // into the exception handler. We have the following register state:
   //    rax,: exception
   //    rbx,: exception handler
   //    rdx: throwing pc
   // So in this case we simply jam rdx into the useless return address and
   // the stack looks just like we want.
   //
   // At this point we need to de-opt.  We save the argument return
   // registers.  We call the first C routine, fetch_unroll_info().  This
   // routine captures the return values and returns a structure which
   // describes the current frame size and the sizes of all replacement frames.
   // The current frame is compiled code and may contain many inlined
   // functions, each with their own JVM state.  We pop the current frame, then
   // push all the new frames.  Then we call the C routine unpack_frames() to
   // populate these frames.  Finally unpack_frames() returns us the new target
   // address.  Notice that callee-save registers are BLOWN here; they have
   // already been captured in the vframeArray at the time the return PC was
   // patched.
   address start = __ pc();
   Label cont;
   // Prolog for non exception case!
   // Save everything in sight.
   map = RegisterSaver::save_live_registers(masm, additional_words, &frame_size_in_words, false);
   // Normal deoptimization
   __ push(Deoptimization::Unpack_deopt);
   __ jmp(cont);
   int reexecute_offset = __ pc() - start;
   // Reexecute case
   // return address is the pc describes what bci to do re-execute at
   // No need to update map as each call to save_live_registers will produce identical oopmap
   (void) RegisterSaver::save_live_registers(masm, additional_words, &frame_size_in_words, false);
   __ push(Deoptimization::Unpack_reexecute);
   __ jmp(cont);
   int exception_offset = __ pc() - start;
   // Prolog for exception case
   // all registers are dead at this entry point, except for rax, and
   // rdx which contain the exception oop and exception pc
   // respectively.  Set them in TLS and fall thru to the
   // unpack_with_exception_in_tls entry point.
   __ get_thread(rdi);
   __ movptr(Address(rdi, JavaThread::exception_pc_offset()), rdx);
   __ movptr(Address(rdi, JavaThread::exception_oop_offset()), rax);
   int exception_in_tls_offset = __ pc() - start;
   // new implementation because exception oop is now passed in JavaThread
   // Prolog for exception case
   // All registers must be preserved because they might be used by LinearScan
   // Exceptiop oop and throwing PC are passed in JavaThread
   // tos: stack at point of call to method that threw the exception (i.e. only
   // args are on the stack, no return address)
   // make room on stack for the return address
   // It will be patched later with the throwing pc. The correct value is not
   // available now because loading it from memory would destroy registers.
   __ push(0);
   // Save everything in sight.
   // No need to update map as each call to save_live_registers will produce identical oopmap
   (void) RegisterSaver::save_live_registers(masm, additional_words, &frame_size_in_words, false);
   // Now it is safe to overwrite any register
   // store the correct deoptimization type
   __ push(Deoptimization::Unpack_exception);
   // load throwing pc from JavaThread and patch it as the return address
   // of the current frame. Then clear the field in JavaThread
   __ get_thread(rdi);
   __ movptr(rdx, Address(rdi, JavaThread::exception_pc_offset()));
   __ movptr(Address(rbp, wordSize), rdx);
   __ movptr(Address(rdi, JavaThread::exception_pc_offset()), NULL_WORD);
 #ifdef ASSERT
   // verify that there is really an exception oop in JavaThread
   __ movptr(rax, Address(rdi, JavaThread::exception_oop_offset()));
   __ verify_oop(rax);
   // verify that there is no pending exception
   Label no_pending_exception;
   __ movptr(rax, Address(rdi, Thread::pending_exception_offset()));
   __ testptr(rax, rax);
   __ jcc(Assembler::zero, no_pending_exception);
   __ stop("must not have pending exception here");
   __ bind(no_pending_exception);
 #endif
   __ bind(cont);
   // Compiled code leaves the floating point stack dirty, empty it.
   __ empty_FPU_stack();
   // Call C code.  Need thread and this frame, but NOT official VM entry
   // crud.  We cannot block on this call, no GC can happen.
   __ get_thread(rcx);
   __ push(rcx);
   // fetch_unroll_info needs to call last_java_frame()
   __ set_last_Java_frame(rcx, noreg, noreg, NULL);
   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::fetch_unroll_info)));
   // Need to have an oopmap that tells fetch_unroll_info where to
   // find any register it might need.
   oop_maps->add_gc_map( __ pc()-start, map);
   // Discard arg to fetch_unroll_info
   __ pop(rcx);
   __ get_thread(rcx);
   __ reset_last_Java_frame(rcx, false, false);
   // Load UnrollBlock into EDI
   __ mov(rdi, rax);
   // Move the unpack kind to a safe place in the UnrollBlock because
   // we are very short of registers
   Address unpack_kind(rdi, Deoptimization::UnrollBlock::unpack_kind_offset_in_bytes());
   // retrieve the deopt kind from where we left it.
   __ pop(rax);
   __ movl(unpack_kind, rax);                      // save the unpack_kind value
    Label noException;
   __ cmpl(rax, Deoptimization::Unpack_exception);   // Was exception pending?
   __ jcc(Assembler::notEqual, noException);
   __ movptr(rax, Address(rcx, JavaThread::exception_oop_offset()));
   __ movptr(rdx, Address(rcx, JavaThread::exception_pc_offset()));
   __ movptr(Address(rcx, JavaThread::exception_oop_offset()), NULL_WORD);
   __ movptr(Address(rcx, JavaThread::exception_pc_offset()), NULL_WORD);
   __ verify_oop(rax);
   // Overwrite the result registers with the exception results.
   __ movptr(Address(rsp, RegisterSaver::raxOffset()*wordSize), rax);
   __ movptr(Address(rsp, RegisterSaver::rdxOffset()*wordSize), rdx);
   __ bind(noException);
   // Stack is back to only having register save data on the stack.
   // Now restore the result registers. Everything else is either dead or captured
   // in the vframeArray.
   RegisterSaver::restore_result_registers(masm);
   // Non standard control word may be leaked out through a safepoint blob, and we can
   // deopt at a poll point with the non standard control word. However, we should make
   // sure the control word is correct after restore_result_registers.
   __ fldcw(ExternalAddress(StubRoutines::addr_fpu_cntrl_wrd_std()));
   // All of the register save area has been popped of the stack. Only the
   // return address remains.
   // Pop all the frames we must move/replace.
   //
   // Frame picture (youngest to oldest)
   // 1: self-frame (no frame link)
   // 2: deopting frame  (no frame link)
   // 3: caller of deopting frame (could be compiled/interpreted).
   //
   // Note: by leaving the return address of self-frame on the stack
   // and using the size of frame 2 to adjust the stack
   // when we are done the return to frame 3 will still be on the stack.
   // Pop deoptimized frame
   __ addptr(rsp, Address(rdi,Deoptimization::UnrollBlock::size_of_deoptimized_frame_offset_in_bytes()));
   // sp should be pointing at the return address to the caller (3)
   // Stack bang to make sure there's enough room for these interpreter frames.
   if (UseStackBanging) {
     __ movl(rbx, Address(rdi ,Deoptimization::UnrollBlock::total_frame_sizes_offset_in_bytes()));
     __ bang_stack_size(rbx, rcx);
   }
   // Load array of frame pcs into ECX
   __ movptr(rcx,Address(rdi,Deoptimization::UnrollBlock::frame_pcs_offset_in_bytes()));
   __ pop(rsi); // trash the old pc
   // Load array of frame sizes into ESI
   __ movptr(rsi,Address(rdi,Deoptimization::UnrollBlock::frame_sizes_offset_in_bytes()));
   Address counter(rdi, Deoptimization::UnrollBlock::counter_temp_offset_in_bytes());
   __ movl(rbx, Address(rdi, Deoptimization::UnrollBlock::number_of_frames_offset_in_bytes()));
   __ movl(counter, rbx);
   // Pick up the initial fp we should save
   __ movptr(rbp, Address(rdi, Deoptimization::UnrollBlock::initial_info_offset_in_bytes()));
   // Now adjust the caller's stack to make up for the extra locals
   // but record the original sp so that we can save it in the skeletal interpreter
   // frame and the stack walking of interpreter_sender will get the unextended sp
   // value and not the "real" sp value.
   Address sp_temp(rdi, Deoptimization::UnrollBlock::sender_sp_temp_offset_in_bytes());
   __ movptr(sp_temp, rsp);
   __ movl2ptr(rbx, Address(rdi, Deoptimization::UnrollBlock::caller_adjustment_offset_in_bytes()));
   __ subptr(rsp, rbx);
   // Push interpreter frames in a loop
   Label loop;
   __ bind(loop);
   __ movptr(rbx, Address(rsi, 0));      // Load frame size
 #ifdef CC_INTERP
   __ subptr(rbx, 4*wordSize);           // we'll push pc and ebp by hand and
 #ifdef ASSERT
   __ push(0xDEADDEAD);                  // Make a recognizable pattern
   __ push(0xDEADDEAD);
 #else /* ASSERT */
   __ subptr(rsp, 2*wordSize);           // skip the "static long no_param"
 #endif /* ASSERT */
 #else /* CC_INTERP */
   __ subptr(rbx, 2*wordSize);           // we'll push pc and rbp, by hand
 #endif /* CC_INTERP */
   __ pushptr(Address(rcx, 0));          // save return address
   __ enter();                           // save old & set new rbp,
   __ subptr(rsp, rbx);                  // Prolog!
   __ movptr(rbx, sp_temp);              // sender's sp
 #ifdef CC_INTERP
   __ movptr(Address(rbp,
                   -(sizeof(BytecodeInterpreter)) + in_bytes(byte_offset_of(BytecodeInterpreter, _sender_sp))),
           rbx); // Make it walkable
 #else /* CC_INTERP */
   // This value is corrected by layout_activation_impl
   __ movptr(Address(rbp, frame::interpreter_frame_last_sp_offset * wordSize), NULL_WORD);
   __ movptr(Address(rbp, frame::interpreter_frame_sender_sp_offset * wordSize), rbx); // Make it walkable
 #endif /* CC_INTERP */
   __ movptr(sp_temp, rsp);              // pass to next frame
   __ addptr(rsi, wordSize);             // Bump array pointer (sizes)
   __ addptr(rcx, wordSize);             // Bump array pointer (pcs)
   __ decrementl(counter);             // decrement counter
   __ jcc(Assembler::notZero, loop);
   __ pushptr(Address(rcx, 0));          // save final return address
   // Re-push self-frame
   __ enter();                           // save old & set new rbp,
   //  Return address and rbp, are in place
   // We'll push additional args later. Just allocate a full sized
   // register save area
   __ subptr(rsp, (frame_size_in_words-additional_words - 2) * wordSize);
   // Restore frame locals after moving the frame
   __ movptr(Address(rsp, RegisterSaver::raxOffset()*wordSize), rax);
   __ movptr(Address(rsp, RegisterSaver::rdxOffset()*wordSize), rdx);
   __ fstp_d(Address(rsp, RegisterSaver::fpResultOffset()*wordSize));   // Pop float stack and store in local
   if( UseSSE>=2 ) __ movdbl(Address(rsp, RegisterSaver::xmm0Offset()*wordSize), xmm0);
   if( UseSSE==1 ) __ movflt(Address(rsp, RegisterSaver::xmm0Offset()*wordSize), xmm0);
   // Set up the args to unpack_frame
   __ pushl(unpack_kind);                     // get the unpack_kind value
   __ get_thread(rcx);
   __ push(rcx);
   // set last_Java_sp, last_Java_fp
   __ set_last_Java_frame(rcx, noreg, rbp, NULL);
   // Call C code.  Need thread but NOT official VM entry
   // crud.  We cannot block on this call, no GC can happen.  Call should
   // restore return values to their stack-slots with the new SP.
   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::unpack_frames)));
   // Set an oopmap for the call site
   oop_maps->add_gc_map( __ pc()-start, new OopMap( frame_size_in_words, 0 ));
   // rax, contains the return result type
   __ push(rax);
   __ get_thread(rcx);
   __ reset_last_Java_frame(rcx, false, false);
   // Collect return values
   __ movptr(rax,Address(rsp, (RegisterSaver::raxOffset() + additional_words + 1)*wordSize));
   __ movptr(rdx,Address(rsp, (RegisterSaver::rdxOffset() + additional_words + 1)*wordSize));
   // Clear floating point stack before returning to interpreter
   __ empty_FPU_stack();
   // Check if we should push the float or double return value.
   Label results_done, yes_double_value;
   __ cmpl(Address(rsp, 0), T_DOUBLE);
   __ jcc (Assembler::zero, yes_double_value);
   __ cmpl(Address(rsp, 0), T_FLOAT);
   __ jcc (Assembler::notZero, results_done);
   // return float value as expected by interpreter
   if( UseSSE>=1 ) __ movflt(xmm0, Address(rsp, (RegisterSaver::xmm0Offset() + additional_words + 1)*wordSize));
   else            __ fld_d(Address(rsp, (RegisterSaver::fpResultOffset() + additional_words + 1)*wordSize));
   __ jmp(results_done);
   // return double value as expected by interpreter
   __ bind(yes_double_value);
   if( UseSSE>=2 ) __ movdbl(xmm0, Address(rsp, (RegisterSaver::xmm0Offset() + additional_words + 1)*wordSize));
   else            __ fld_d(Address(rsp, (RegisterSaver::fpResultOffset() + additional_words + 1)*wordSize));
   __ bind(results_done);
   // Pop self-frame.
   __ leave();                              // Epilog!
   // Jump to interpreter
   __ ret(0);
   // -------------
   // make sure all code is generated
   masm->flush();
   _deopt_blob = DeoptimizationBlob::create( &buffer, oop_maps, 0, exception_offset, reexecute_offset, frame_size_in_words);
   _deopt_blob->set_unpack_with_exception_in_tls_offset(exception_in_tls_offset);
 }
 #ifdef COMPILER2
 //------------------------------generate_uncommon_trap_blob--------------------
 void SharedRuntime::generate_uncommon_trap_blob() {
   // allocate space for the code
   ResourceMark rm;
   // setup code generation tools
   CodeBuffer   buffer("uncommon_trap_blob", 512, 512);
   MacroAssembler* masm = new MacroAssembler(&buffer);
   enum frame_layout {
     arg0_off,      // thread                     sp + 0 // Arg location for
     arg1_off,      // unloaded_class_index       sp + 1 // calling C
     // The frame sender code expects that rbp will be in the "natural" place and
     // will override any oopMap setting for it. We must therefore force the layout
     // so that it agrees with the frame sender code.
     rbp_off,       // callee saved register      sp + 2
     return_off,    // slot for return address    sp + 3
     framesize
   };
   address start = __ pc();
   // Push self-frame.
   __ subptr(rsp, return_off*wordSize);     // Epilog!
   // rbp, is an implicitly saved callee saved register (i.e. the calling
   // convention will save restore it in prolog/epilog) Other than that
   // there are no callee save registers no that adapter frames are gone.
   __ movptr(Address(rsp, rbp_off*wordSize), rbp);
   // Clear the floating point exception stack
   __ empty_FPU_stack();
   // set last_Java_sp
   __ get_thread(rdx);
   __ set_last_Java_frame(rdx, noreg, noreg, NULL);
   // Call C code.  Need thread but NOT official VM entry
   // crud.  We cannot block on this call, no GC can happen.  Call should
   // capture callee-saved registers as well as return values.
   __ movptr(Address(rsp, arg0_off*wordSize), rdx);
   // argument already in ECX
   __ movl(Address(rsp, arg1_off*wordSize),rcx);
   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::uncommon_trap)));
   // Set an oopmap for the call site
   OopMapSet *oop_maps = new OopMapSet();
   OopMap* map =  new OopMap( framesize, 0 );
   // No oopMap for rbp, it is known implicitly
   oop_maps->add_gc_map( __ pc()-start, map);
   __ get_thread(rcx);
   __ reset_last_Java_frame(rcx, false, false);
   // Load UnrollBlock into EDI
   __ movptr(rdi, rax);
   // Pop all the frames we must move/replace.
   //
   // Frame picture (youngest to oldest)
   // 1: self-frame (no frame link)
   // 2: deopting frame  (no frame link)
   // 3: caller of deopting frame (could be compiled/interpreted).
   // Pop self-frame.  We have no frame, and must rely only on EAX and ESP.
   __ addptr(rsp,(framesize-1)*wordSize);     // Epilog!
   // Pop deoptimized frame
   __ movl2ptr(rcx, Address(rdi,Deoptimization::UnrollBlock::size_of_deoptimized_frame_offset_in_bytes()));
   __ addptr(rsp, rcx);
   // sp should be pointing at the return address to the caller (3)
   // Stack bang to make sure there's enough room for these interpreter frames.
   if (UseStackBanging) {
     __ movl(rbx, Address(rdi ,Deoptimization::UnrollBlock::total_frame_sizes_offset_in_bytes()));
     __ bang_stack_size(rbx, rcx);
   }
   // Load array of frame pcs into ECX
   __ movl(rcx,Address(rdi,Deoptimization::UnrollBlock::frame_pcs_offset_in_bytes()));
   __ pop(rsi); // trash the pc
   // Load array of frame sizes into ESI
   __ movptr(rsi,Address(rdi,Deoptimization::UnrollBlock::frame_sizes_offset_in_bytes()));
   Address counter(rdi, Deoptimization::UnrollBlock::counter_temp_offset_in_bytes());
   __ movl(rbx, Address(rdi, Deoptimization::UnrollBlock::number_of_frames_offset_in_bytes()));
   __ movl(counter, rbx);
   // Pick up the initial fp we should save
   __ movptr(rbp, Address(rdi, Deoptimization::UnrollBlock::initial_info_offset_in_bytes()));
   // Now adjust the caller's stack to make up for the extra locals
   // but record the original sp so that we can save it in the skeletal interpreter
   // frame and the stack walking of interpreter_sender will get the unextended sp
   // value and not the "real" sp value.
   Address sp_temp(rdi, Deoptimization::UnrollBlock::sender_sp_temp_offset_in_bytes());
   __ movptr(sp_temp, rsp);
   __ movl(rbx, Address(rdi, Deoptimization::UnrollBlock::caller_adjustment_offset_in_bytes()));
   __ subptr(rsp, rbx);
   // Push interpreter frames in a loop
   Label loop;
   __ bind(loop);
   __ movptr(rbx, Address(rsi, 0));      // Load frame size
 #ifdef CC_INTERP
   __ subptr(rbx, 4*wordSize);           // we'll push pc and ebp by hand and
 #ifdef ASSERT
   __ push(0xDEADDEAD);                  // Make a recognizable pattern
   __ push(0xDEADDEAD);                  // (parm to RecursiveInterpreter...)
 #else /* ASSERT */
   __ subptr(rsp, 2*wordSize);           // skip the "static long no_param"
 #endif /* ASSERT */
 #else /* CC_INTERP */
   __ subptr(rbx, 2*wordSize);           // we'll push pc and rbp, by hand
 #endif /* CC_INTERP */
   __ pushptr(Address(rcx, 0));          // save return address
   __ enter();                           // save old & set new rbp,
   __ subptr(rsp, rbx);                  // Prolog!
   __ movptr(rbx, sp_temp);              // sender's sp
 #ifdef CC_INTERP
   __ movptr(Address(rbp,
                   -(sizeof(BytecodeInterpreter)) + in_bytes(byte_offset_of(BytecodeInterpreter, _sender_sp))),
           rbx); // Make it walkable
 #else /* CC_INTERP */
   // This value is corrected by layout_activation_impl
   __ movptr(Address(rbp, frame::interpreter_frame_last_sp_offset * wordSize), NULL_WORD );
   __ movptr(Address(rbp, frame::interpreter_frame_sender_sp_offset * wordSize), rbx); // Make it walkable
 #endif /* CC_INTERP */
   __ movptr(sp_temp, rsp);              // pass to next frame
   __ addptr(rsi, wordSize);             // Bump array pointer (sizes)
   __ addptr(rcx, wordSize);             // Bump array pointer (pcs)
   __ decrementl(counter);             // decrement counter
   __ jcc(Assembler::notZero, loop);
   __ pushptr(Address(rcx, 0));            // save final return address
   // Re-push self-frame
   __ enter();                           // save old & set new rbp,
   __ subptr(rsp, (framesize-2) * wordSize);   // Prolog!
   // set last_Java_sp, last_Java_fp
   __ get_thread(rdi);
   __ set_last_Java_frame(rdi, noreg, rbp, NULL);
   // Call C code.  Need thread but NOT official VM entry
   // crud.  We cannot block on this call, no GC can happen.  Call should
   // restore return values to their stack-slots with the new SP.
   __ movptr(Address(rsp,arg0_off*wordSize),rdi);
   __ movl(Address(rsp,arg1_off*wordSize), Deoptimization::Unpack_uncommon_trap);
   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::unpack_frames)));
   // Set an oopmap for the call site
   oop_maps->add_gc_map( __ pc()-start, new OopMap( framesize, 0 ) );
   __ get_thread(rdi);
   __ reset_last_Java_frame(rdi, true, false);
   // Pop self-frame.
   __ leave();     // Epilog!
   // Jump to interpreter
   __ ret(0);
   // -------------
   // make sure all code is generated
   masm->flush();
    _uncommon_trap_blob = UncommonTrapBlob::create(&buffer, oop_maps, framesize);
 }
 #endif // COMPILER2
 //------------------------------generate_handler_blob------
 //
 // Generate a special Compile2Runtime blob that saves all registers,
 // setup oopmap, and calls safepoint code to stop the compiled code for
 // a safepoint.
 //
 SafepointBlob* SharedRuntime::generate_handler_blob(address call_ptr, bool cause_return) {
   // Account for thread arg in our frame
   const int additional_words = 1;
   int frame_size_in_words;
   assert (StubRoutines::forward_exception_entry() != NULL, "must be generated before");
   ResourceMark rm;
   OopMapSet *oop_maps = new OopMapSet();
   OopMap* map;
   // allocate space for the code
   // setup code generation tools
   CodeBuffer   buffer("handler_blob", 1024, 512);
   MacroAssembler* masm = new MacroAssembler(&buffer);
   const Register java_thread = rdi; // callee-saved for VC++
   address start   = __ pc();
   address call_pc = NULL;
   // If cause_return is true we are at a poll_return and there is
   // the return address on the stack to the caller on the nmethod
   // that is safepoint. We can leave this return on the stack and
   // effectively complete the return and safepoint in the caller.
   // Otherwise we push space for a return address that the safepoint
   // handler will install later to make the stack walking sensible.
   if( !cause_return )
     __ push(rbx);                // Make room for return address (or push it again)
   map = RegisterSaver::save_live_registers(masm, additional_words, &frame_size_in_words, false);
   // The following is basically a call_VM. However, we need the precise
   // address of the call in order to generate an oopmap. Hence, we do all the
   // work ourselves.
   // Push thread argument and setup last_Java_sp
   __ get_thread(java_thread);
   __ push(java_thread);
   __ set_last_Java_frame(java_thread, noreg, noreg, NULL);
   // if this was not a poll_return then we need to correct the return address now.
   if( !cause_return ) {
     __ movptr(rax, Address(java_thread, JavaThread::saved_exception_pc_offset()));
     __ movptr(Address(rbp, wordSize), rax);
   }
   // do the call
   __ call(RuntimeAddress(call_ptr));
   // Set an oopmap for the call site.  This oopmap will map all
   // oop-registers and debug-info registers as callee-saved.  This
   // will allow deoptimization at this safepoint to find all possible
   // debug-info recordings, as well as let GC find all oops.
   oop_maps->add_gc_map( __ pc() - start, map);
   // Discard arg
   __ pop(rcx);
   Label noException;
   // Clear last_Java_sp again
   __ get_thread(java_thread);
   __ reset_last_Java_frame(java_thread, false, false);
   __ cmpptr(Address(java_thread, Thread::pending_exception_offset()), (int32_t)NULL_WORD);
   __ jcc(Assembler::equal, noException);
   // Exception pending
   RegisterSaver::restore_live_registers(masm);
   __ jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
   __ bind(noException);
   // Normal exit, register restoring and exit
   RegisterSaver::restore_live_registers(masm);
   __ ret(0);
   // make sure all code is generated
   masm->flush();
   // Fill-out other meta info
   return SafepointBlob::create(&buffer, oop_maps, frame_size_in_words);
 }
 //
 // generate_resolve_blob - call resolution (static/virtual/opt-virtual/ic-miss
 //
 // Generate a stub that calls into vm to find out the proper destination
 // of a java call. All the argument registers are live at this point
 // but since this is generic code we don't know what they are and the caller
 // must do any gc of the args.
 //
 RuntimeStub* SharedRuntime::generate_resolve_blob(address destination, const char* name) {
   assert (StubRoutines::forward_exception_entry() != NULL, "must be generated before");
   // allocate space for the code
   ResourceMark rm;
   CodeBuffer buffer(name, 1000, 512);
   MacroAssembler* masm                = new MacroAssembler(&buffer);
   int frame_size_words;
   enum frame_layout {
                 thread_off,
                 extra_words };
   OopMapSet *oop_maps = new OopMapSet();
   OopMap* map = NULL;
   int start = __ offset();
   map = RegisterSaver::save_live_registers(masm, extra_words, &frame_size_words);
   int frame_complete = __ offset();
   const Register thread = rdi;
   __ get_thread(rdi);
   __ push(thread);
   __ set_last_Java_frame(thread, noreg, rbp, NULL);
   __ call(RuntimeAddress(destination));
   // Set an oopmap for the call site.
   // We need this not only for callee-saved registers, but also for volatile
   // registers that the compiler might be keeping live across a safepoint.
   oop_maps->add_gc_map( __ offset() - start, map);
   // rax, contains the address we are going to jump to assuming no exception got installed
   __ addptr(rsp, wordSize);
   // clear last_Java_sp
   __ reset_last_Java_frame(thread, true, false);
   // check for pending exceptions
   Label pending;
   __ cmpptr(Address(thread, Thread::pending_exception_offset()), (int32_t)NULL_WORD);
   __ jcc(Assembler::notEqual, pending);
   // get the returned Method*
   __ get_vm_result_2(rbx, thread);
   __ movptr(Address(rsp, RegisterSaver::rbx_offset() * wordSize), rbx);
   __ movptr(Address(rsp, RegisterSaver::rax_offset() * wordSize), rax);
   RegisterSaver::restore_live_registers(masm);
   // We are back the the original state on entry and ready to go.
   __ jmp(rax);
   // Pending exception after the safepoint
   __ bind(pending);
   RegisterSaver::restore_live_registers(masm);
   // exception pending => remove activation and forward to exception handler
   __ get_thread(thread);
   __ movptr(Address(thread, JavaThread::vm_result_offset()), NULL_WORD);
   __ movptr(rax, Address(thread, Thread::pending_exception_offset()));
   __ jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
   // -------------
   // make sure all code is generated
   masm->flush();
   // return the  blob
   // frame_size_words or bytes??
   return RuntimeStub::new_runtime_stub(name, &buffer, frame_complete, frame_size_words, oop_maps, true);
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/cpu/x86/vm/sharedRuntime_x86_32.cpp@8a02ca5e5576 (annotated)

src/cpu/x86/vm/sharedRuntime_x86_32.cpp