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

src/cpu/x86/vm/sharedRuntime_x86_64.cpp@a49a647afe9a (annotated)

src/cpu/x86/vm/sharedRuntime_x86_64.cpp

Fri, 11 Apr 2008 09:56:35 -0400

author: kamg
date: Fri, 11 Apr 2008 09:56:35 -0400
changeset 545: a49a647afe9a
parent 435: a61af66fc99e
child 548: ba764ed4b6f2
permissions: -rw-r--r--

Merge

 /*
  * Copyright 2003-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  * CA 95054 USA or visit www.sun.com if you need additional information or
  * have any questions.
  *
  */
 #include "incls/_precompiled.incl"
 #include "incls/_sharedRuntime_x86_64.cpp.incl"
 DeoptimizationBlob *SharedRuntime::_deopt_blob;
 #ifdef COMPILER2
 UncommonTrapBlob   *SharedRuntime::_uncommon_trap_blob;
 ExceptionBlob      *OptoRuntime::_exception_blob;
 #endif // COMPILER2
 SafepointBlob      *SharedRuntime::_polling_page_safepoint_handler_blob;
 SafepointBlob      *SharedRuntime::_polling_page_return_handler_blob;
 RuntimeStub*       SharedRuntime::_wrong_method_blob;
 RuntimeStub*       SharedRuntime::_ic_miss_blob;
 RuntimeStub*       SharedRuntime::_resolve_opt_virtual_call_blob;
 RuntimeStub*       SharedRuntime::_resolve_virtual_call_blob;
 RuntimeStub*       SharedRuntime::_resolve_static_call_blob;
 #define __ masm->
 class SimpleRuntimeFrame {
   public:
   // Most of the runtime stubs have this simple frame layout.
   // This class exists to make the layout shared in one place.
   // Offsets are for compiler stack slots, which are jints.
   enum layout {
     // 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 = frame::arg_reg_save_area_bytes/BytesPerInt,
     rbp_off2,
     return_off, return_off2,
     framesize
   };
 };
 class RegisterSaver {
   // Capture info about frame layout.  Layout offsets are in jint
   // units because compiler frame slots are jints.
 #define DEF_XMM_OFFS(regnum) xmm ## regnum ## _off = xmm_off + (regnum)*16/BytesPerInt, xmm ## regnum ## H_off
   enum layout {
     fpu_state_off = frame::arg_reg_save_area_bytes/BytesPerInt, // fxsave save area
     xmm_off       = fpu_state_off + 160/BytesPerInt,            // offset in fxsave save area
     DEF_XMM_OFFS(0),
     DEF_XMM_OFFS(1),
     DEF_XMM_OFFS(2),
     DEF_XMM_OFFS(3),
     DEF_XMM_OFFS(4),
     DEF_XMM_OFFS(5),
     DEF_XMM_OFFS(6),
     DEF_XMM_OFFS(7),
     DEF_XMM_OFFS(8),
     DEF_XMM_OFFS(9),
     DEF_XMM_OFFS(10),
     DEF_XMM_OFFS(11),
     DEF_XMM_OFFS(12),
     DEF_XMM_OFFS(13),
     DEF_XMM_OFFS(14),
     DEF_XMM_OFFS(15),
     fpu_state_end = fpu_state_off + ((FPUStateSizeInWords-1)*wordSize / BytesPerInt),
     fpu_stateH_end,
     r15_off, r15H_off,
     r14_off, r14H_off,
     r13_off, r13H_off,
     r12_off, r12H_off,
     r11_off, r11H_off,
     r10_off, r10H_off,
     r9_off,  r9H_off,
     r8_off,  r8H_off,
     rdi_off, rdiH_off,
     rsi_off, rsiH_off,
     ignore_off, ignoreH_off,  // extra copy of rbp
     rsp_off, rspH_off,
     rbx_off, rbxH_off,
     rdx_off, rdxH_off,
     rcx_off, rcxH_off,
     rax_off, raxH_off,
     // 16-byte stack alignment fill word: see MacroAssembler::push/pop_IU_state
     align_off, alignH_off,
     flags_off, flagsH_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, rbpH_off,        // copy of rbp we will restore
     return_off, returnH_off,  // slot for return address
     reg_save_size             // size in compiler stack slots
   };
  public:
   static OopMap* save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words);
   static void restore_live_registers(MacroAssembler* masm);
   // Offsets into the register save area
   // Used by deoptimization when it is managing result register
   // values on its own
   static int rax_offset_in_bytes(void)    { return BytesPerInt * rax_off; }
   static int rbx_offset_in_bytes(void)    { return BytesPerInt * rbx_off; }
   static int xmm0_offset_in_bytes(void)   { return BytesPerInt * xmm0_off; }
   static int return_offset_in_bytes(void) { return BytesPerInt * return_off; }
   // During deoptimization only the result registers 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) {
   // Always make the frame size 16-byte aligned
   int frame_size_in_bytes = round_to(additional_frame_words*wordSize +
                                      reg_save_size*BytesPerInt, 16);
   // OopMap frame size is in compiler stack slots (jint's) not bytes or words
   int frame_size_in_slots = frame_size_in_bytes / BytesPerInt;
   // The caller will allocate additional_frame_words
   int additional_frame_slots = additional_frame_words*wordSize / BytesPerInt;
   // CodeBlob frame size is in words.
   int frame_size_in_words = frame_size_in_bytes / wordSize;
   *total_frame_words = frame_size_in_words;
   // Save registers, fpu state, and flags.
   // We assume caller has already pushed the return address onto the
   // stack, so rsp is 8-byte aligned here.
   // We push rpb twice in this sequence because we want the real rbp
   // to be under the return like a normal enter.
   __ enter();          // rsp becomes 16-byte aligned here
   __ push_CPU_state(); // Push a multiple of 16 bytes
   if (frame::arg_reg_save_area_bytes != 0) {
     // Allocate argument register save area
     __ subq(rsp, frame::arg_reg_save_area_bytes);
   }
   // 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_size_in_slots, 0);
   map->set_callee_saved(VMRegImpl::stack2reg( rax_off  + additional_frame_slots), rax->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg( rcx_off  + additional_frame_slots), rcx->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg( rdx_off  + additional_frame_slots), rdx->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg( rbx_off  + additional_frame_slots), rbx->as_VMReg());
   // rbp location is known implicitly by the frame sender code, needs no oopmap
   // and the location where rbp was saved by is ignored
   map->set_callee_saved(VMRegImpl::stack2reg( rsi_off  + additional_frame_slots), rsi->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg( rdi_off  + additional_frame_slots), rdi->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg( r8_off   + additional_frame_slots), r8->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg( r9_off   + additional_frame_slots), r9->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg( r10_off  + additional_frame_slots), r10->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg( r11_off  + additional_frame_slots), r11->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg( r12_off  + additional_frame_slots), r12->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg( r13_off  + additional_frame_slots), r13->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg( r14_off  + additional_frame_slots), r14->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg( r15_off  + additional_frame_slots), r15->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm0_off  + additional_frame_slots), xmm0->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm1_off  + additional_frame_slots), xmm1->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm2_off  + additional_frame_slots), xmm2->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm3_off  + additional_frame_slots), xmm3->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm4_off  + additional_frame_slots), xmm4->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm5_off  + additional_frame_slots), xmm5->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm6_off  + additional_frame_slots), xmm6->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm7_off  + additional_frame_slots), xmm7->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm8_off  + additional_frame_slots), xmm8->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm9_off  + additional_frame_slots), xmm9->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm10_off + additional_frame_slots), xmm10->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm11_off + additional_frame_slots), xmm11->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm12_off + additional_frame_slots), xmm12->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm13_off + additional_frame_slots), xmm13->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm14_off + additional_frame_slots), xmm14->as_VMReg());
   map->set_callee_saved(VMRegImpl::stack2reg(xmm15_off + additional_frame_slots), xmm15->as_VMReg());
   // %%% These should all be a waste but we'll keep things as they were for now
   if (true) {
     map->set_callee_saved(VMRegImpl::stack2reg( raxH_off  + additional_frame_slots),
                           rax->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg( rcxH_off  + additional_frame_slots),
                           rcx->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg( rdxH_off  + additional_frame_slots),
                           rdx->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg( rbxH_off  + additional_frame_slots),
                           rbx->as_VMReg()->next());
     // rbp location is known implicitly by the frame sender code, needs no oopmap
     map->set_callee_saved(VMRegImpl::stack2reg( rsiH_off  + additional_frame_slots),
                           rsi->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg( rdiH_off  + additional_frame_slots),
                           rdi->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg( r8H_off   + additional_frame_slots),
                           r8->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg( r9H_off   + additional_frame_slots),
                           r9->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg( r10H_off  + additional_frame_slots),
                           r10->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg( r11H_off  + additional_frame_slots),
                           r11->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg( r12H_off  + additional_frame_slots),
                           r12->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg( r13H_off  + additional_frame_slots),
                           r13->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg( r14H_off  + additional_frame_slots),
                           r14->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg( r15H_off  + additional_frame_slots),
                           r15->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm0H_off  + additional_frame_slots),
                           xmm0->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm1H_off  + additional_frame_slots),
                           xmm1->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm2H_off  + additional_frame_slots),
                           xmm2->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm3H_off  + additional_frame_slots),
                           xmm3->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm4H_off  + additional_frame_slots),
                           xmm4->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm5H_off  + additional_frame_slots),
                           xmm5->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm6H_off  + additional_frame_slots),
                           xmm6->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm7H_off  + additional_frame_slots),
                           xmm7->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm8H_off  + additional_frame_slots),
                           xmm8->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm9H_off  + additional_frame_slots),
                           xmm9->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm10H_off + additional_frame_slots),
                           xmm10->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm11H_off + additional_frame_slots),
                           xmm11->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm12H_off + additional_frame_slots),
                           xmm12->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm13H_off + additional_frame_slots),
                           xmm13->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm14H_off + additional_frame_slots),
                           xmm14->as_VMReg()->next());
     map->set_callee_saved(VMRegImpl::stack2reg(xmm15H_off + additional_frame_slots),
                           xmm15->as_VMReg()->next());
   }
   return map;
 }
 void RegisterSaver::restore_live_registers(MacroAssembler* masm) {
   if (frame::arg_reg_save_area_bytes != 0) {
     // Pop arg register save area
     __ addq(rsp, frame::arg_reg_save_area_bytes);
   }
   // Recover CPU state
   __ pop_CPU_state();
   // Get the rbp described implicitly by the calling convention (no oopMap)
   __ popq(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 restored 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.
   // Restore fp result register
   __ movdbl(xmm0, Address(rsp, xmm0_offset_in_bytes()));
   // Restore integer result register
   __ movq(rax, Address(rsp, rax_offset_in_bytes()));
   // Pop all of the register save are off the stack except the return address
   __ addq(rsp, return_offset_in_bytes());
 }
 // 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() + 4) * 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 VMRegImpl::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 64-bit
 // integer registers.
 // 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 Java calling convention is a "shifted" version of the C ABI.
 // By skipping the first C ABI register we can call non-static jni methods
 // with small numbers of arguments without having to shuffle the arguments
 // at all. Since we control the java ABI we ought to at least get some
 // advantage out of it.
 int SharedRuntime::java_calling_convention(const BasicType *sig_bt,
                                            VMRegPair *regs,
                                            int total_args_passed,
                                            int is_outgoing) {
   // Create the mapping between argument positions and
   // registers.
   static const Register INT_ArgReg[Argument::n_int_register_parameters_j] = {
     j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5
   };
   static const XMMRegister FP_ArgReg[Argument::n_float_register_parameters_j] = {
     j_farg0, j_farg1, j_farg2, j_farg3,
     j_farg4, j_farg5, j_farg6, j_farg7
   };
   uint int_args = 0;
   uint fp_args = 0;
   uint stk_args = 0; // inc by 2 each time
   for (int i = 0; i < total_args_passed; i++) {
     switch (sig_bt[i]) {
     case T_BOOLEAN:
     case T_CHAR:
     case T_BYTE:
     case T_SHORT:
     case T_INT:
       if (int_args < Argument::n_int_register_parameters_j) {
         regs[i].set1(INT_ArgReg[int_args++]->as_VMReg());
       } else {
         regs[i].set1(VMRegImpl::stack2reg(stk_args));
         stk_args += 2;
       }
       break;
     case T_VOID:
       // halves of T_LONG or T_DOUBLE
       assert(i != 0 && (sig_bt[i - 1] == T_LONG || sig_bt[i - 1] == T_DOUBLE), "expecting half");
       regs[i].set_bad();
       break;
     case T_LONG:
       assert(sig_bt[i + 1] == T_VOID, "expecting half");
       // fall through
     case T_OBJECT:
     case T_ARRAY:
     case T_ADDRESS:
       if (int_args < Argument::n_int_register_parameters_j) {
         regs[i].set2(INT_ArgReg[int_args++]->as_VMReg());
       } else {
         regs[i].set2(VMRegImpl::stack2reg(stk_args));
         stk_args += 2;
       }
       break;
     case T_FLOAT:
       if (fp_args < Argument::n_float_register_parameters_j) {
         regs[i].set1(FP_ArgReg[fp_args++]->as_VMReg());
       } else {
         regs[i].set1(VMRegImpl::stack2reg(stk_args));
         stk_args += 2;
       }
       break;
     case T_DOUBLE:
       assert(sig_bt[i + 1] == T_VOID, "expecting half");
       if (fp_args < Argument::n_float_register_parameters_j) {
         regs[i].set2(FP_ArgReg[fp_args++]->as_VMReg());
       } else {
         regs[i].set2(VMRegImpl::stack2reg(stk_args));
         stk_args += 2;
       }
       break;
     default:
       ShouldNotReachHere();
       break;
     }
   }
   return round_to(stk_args, 2);
 }
 // Patch the callers callsite with entry to compiled code if it exists.
 static void patch_callers_callsite(MacroAssembler *masm) {
   Label L;
   __ verify_oop(rbx);
   __ cmpq(Address(rbx, in_bytes(methodOopDesc::code_offset())), (int)NULL_WORD);
   __ jcc(Assembler::equal, L);
   // Save the current stack pointer
   __ movq(r13, rsp);
   // 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
   __ movq(rax, Address(rsp, 0));
   // align stack so push_CPU_state doesn't fault
   __ andq(rsp, -(StackAlignmentInBytes));
   __ push_CPU_state();
   __ verify_oop(rbx);
   // VM needs caller's callsite
   // VM needs target method
   // This needs to be a long call since we will relocate this adapter to
   // the codeBuffer and it may not reach
   // Allocate argument register save area
   if (frame::arg_reg_save_area_bytes != 0) {
     __ subq(rsp, frame::arg_reg_save_area_bytes);
   }
   __ movq(c_rarg0, rbx);
   __ movq(c_rarg1, rax);
   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::fixup_callers_callsite)));
   // De-allocate argument register save area
   if (frame::arg_reg_save_area_bytes != 0) {
     __ addq(rsp, frame::arg_reg_save_area_bytes);
   }
   __ pop_CPU_state();
   // restore sp
   __ movq(rsp, r13);
   __ bind(L);
 }
 // Helper function to put tags in interpreter stack.
 static void  tag_stack(MacroAssembler *masm, const BasicType sig, int st_off) {
   if (TaggedStackInterpreter) {
     int tag_offset = st_off + Interpreter::expr_tag_offset_in_bytes(0);
     if (sig == T_OBJECT || sig == T_ARRAY) {
       __ mov64(Address(rsp, tag_offset), frame::TagReference);
     } else if (sig == T_LONG || sig == T_DOUBLE) {
       int next_tag_offset = st_off + Interpreter::expr_tag_offset_in_bytes(1);
       __ mov64(Address(rsp, next_tag_offset), frame::TagValue);
       __ mov64(Address(rsp, tag_offset), frame::TagValue);
     } else {
       __ mov64(Address(rsp, tag_offset), frame::TagValue);
     }
   }
 }
 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);
   // Since all args are passed on the stack, total_args_passed *
   // Interpreter::stackElementSize is the space we need. Plus 1 because
   // we also account for the return address location since
   // we store it first rather than hold it in rax across all the shuffling
   int extraspace = (total_args_passed * Interpreter::stackElementSize()) + wordSize;
   // stack is aligned, keep it that way
   extraspace = round_to(extraspace, 2*wordSize);
   // Get return address
   __ popq(rax);
   // set senderSP value
   __ movq(r13, rsp);
   __ subq(rsp, extraspace);
   // Store the return address in the expected location
   __ movq(Address(rsp, 0), rax);
   // 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;
     }
     // offset to start parameters
     int st_off   = (total_args_passed - i) * Interpreter::stackElementSize() +
                    Interpreter::value_offset_in_bytes();
     int next_off = st_off - Interpreter::stackElementSize();
     // Say 4 args:
     // i   st_off
     // 0   32 T_LONG
     // 1   24 T_VOID
     // 2   16 T_OBJECT
     // 3    8 T_BOOL
     // -    0 return address
     //
     // However to make thing extra confusing. Because we can fit a long/double in
     // a single slot on a 64 bt vm and it would be silly to break them up, the interpreter
     // leaves one slot empty and only stores to a single slot. In this case the
     // slot that is occupied is the T_VOID slot. See I said it was confusing.
     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 rax
       int ld_off = r_1->reg2stack() * VMRegImpl::stack_slot_size + extraspace;
       if (!r_2->is_valid()) {
         // sign extend??
         __ movl(rax, Address(rsp, ld_off));
         __ movq(Address(rsp, st_off), rax);
         tag_stack(masm, sig_bt[i], st_off);
       } else {
         __ movq(rax, Address(rsp, ld_off));
         // Two VMREgs|OptoRegs 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) {
           // ld_off == LSW, ld_off+wordSize == MSW
           // st_off == MSW, next_off == LSW
           __ movq(Address(rsp, next_off), rax);
 #ifdef ASSERT
           // Overwrite the unused slot with known junk
           __ mov64(rax, CONST64(0xdeadffffdeadaaaa));
           __ movq(Address(rsp, st_off), rax);
 #endif /* ASSERT */
           tag_stack(masm, sig_bt[i], next_off);
         } else {
           __ movq(Address(rsp, st_off), rax);
           tag_stack(masm, sig_bt[i], st_off);
         }
       }
     } else if (r_1->is_Register()) {
       Register r = r_1->as_Register();
       if (!r_2->is_valid()) {
         // must be only an int (or less ) so move only 32bits to slot
         // why not sign extend??
         __ movl(Address(rsp, st_off), r);
         tag_stack(masm, sig_bt[i], st_off);
       } else {
         // Two VMREgs|OptoRegs 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
           __ mov64(rax, CONST64(0xdeadffffdeadaaab));
           __ movq(Address(rsp, st_off), rax);
 #endif /* ASSERT */
           __ movq(Address(rsp, next_off), r);
           tag_stack(masm, sig_bt[i], next_off);
         } else {
           __ movq(Address(rsp, st_off), r);
           tag_stack(masm, sig_bt[i], st_off);
         }
       }
     } else {
       assert(r_1->is_XMMRegister(), "");
       if (!r_2->is_valid()) {
         // only a float use just part of the slot
         __ movflt(Address(rsp, st_off), r_1->as_XMMRegister());
         tag_stack(masm, sig_bt[i], st_off);
       } else {
 #ifdef ASSERT
         // Overwrite the unused slot with known junk
         __ mov64(rax, CONST64(0xdeadffffdeadaaac));
         __ movq(Address(rsp, st_off), rax);
 #endif /* ASSERT */
         __ movdbl(Address(rsp, next_off), r_1->as_XMMRegister());
         tag_stack(masm, sig_bt[i], next_off);
       }
     }
   }
   // Schedule the branch target address early.
   __ movq(rcx, Address(rbx, in_bytes(methodOopDesc::interpreter_entry_offset())));
   __ jmp(rcx);
 }
 static void gen_i2c_adapter(MacroAssembler *masm,
                             int total_args_passed,
                             int comp_args_on_stack,
                             const BasicType *sig_bt,
                             const VMRegPair *regs) {
   //
   // We will only enter here from an interpreted frame and never from after
   // passing thru a c2i. Azul allowed this but we do not. If we lose the
   // race and use a c2i we will remain interpreted for the race loser(s).
   // This removes all sorts of headaches on the x86 side and also eliminates
   // the possibility of having c2i -> i2c -> c2i -> ... endless transitions.
   // Note: r13 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.
   // In addition we use r13 to locate all the interpreter args as
   // we must align the stack to 16 bytes on an i2c entry else we
   // lose alignment we expect in all compiled code and register
   // save code can segv when fxsave instructions find improperly
   // aligned stack pointer.
   __ movq(rax, Address(rsp, 0));
   // 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.
     // Convert 4-byte c2 stack slots to words.
     comp_words_on_stack = round_to(comp_args_on_stack*VMRegImpl::stack_slot_size, wordSize)>>LogBytesPerWord;
     // Round up to miminum stack alignment, in wordSize
     comp_words_on_stack = round_to(comp_words_on_stack, 2);
     __ subq(rsp, comp_words_on_stack * wordSize);
   }
   // Ensure compiled code always sees stack at proper alignment
   __ andq(rsp, -16);
   // push the return address and misalign the stack that youngest frame always sees
   // as far as the placement of the call instruction
   __ pushq(rax);
   // 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.
   __ movq(r11, Address(rbx, in_bytes(methodOopDesc::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 + comp_words_on_stack -i)*wordSize;
     // base ld_off on r13 (sender_sp) as the stack alignment makes offsets from rsp
     // unpredictable
     int ld_off = ((total_args_passed - 1) - 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;
       if (!r_2->is_valid()) {
         // sign extend???
         __ movl(rax, Address(r13, ld_off));
         __ movq(Address(rsp, st_off), rax);
       } else {
         //
         // We are using two optoregs. 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 = (sig_bt[i]==T_LONG||sig_bt[i]==T_DOUBLE)?
                            next_off : ld_off;
         __ movq(rax, Address(r13, offset));
         // st_off is LSW (i.e. reg.first())
         __ movq(Address(rsp, st_off), rax);
       }
     } 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 = (sig_bt[i]==T_LONG||sig_bt[i]==T_DOUBLE)?
                            next_off : ld_off;
         // this can be a misaligned move
         __ movq(r, Address(r13, offset));
       } else {
         // sign extend and use a full word?
         __ movl(r, Address(r13, ld_off));
       }
     } else {
       if (!r_2->is_valid()) {
         __ movflt(r_1->as_XMMRegister(), Address(r13, ld_off));
       } else {
         __ movdbl(r_1->as_XMMRegister(), Address(r13, next_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.
   __ movq(Address(r15_thread, JavaThread::callee_target_offset()), rbx);
   // put methodOop where a c2i would expect should we end up there
   // only needed becaus eof c2 resolve stubs return methodOop as a result in
   // rax
   __ movq(rax, rbx);
   __ jmp(r11);
 }
 // ---------------------------------------------------------------
 AdapterHandlerEntry* SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm,
                                                             int total_args_passed,
                                                             int comp_args_on_stack,
                                                             const BasicType *sig_bt,
                                                             const VMRegPair *regs) {
   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 methodOop 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 RBP, get sick).
   address c2i_unverified_entry = __ pc();
   Label skip_fixup;
   Label ok;
   Register holder = rax;
   Register receiver = j_rarg0;
   Register temp = rbx;
   {
     __ verify_oop(holder);
     __ movq(temp, Address(receiver, oopDesc::klass_offset_in_bytes()));
     __ verify_oop(temp);
     __ cmpq(temp, Address(holder, compiledICHolderOopDesc::holder_klass_offset()));
     __ movq(rbx, Address(holder, compiledICHolderOopDesc::holder_method_offset()));
     __ jcc(Assembler::equal, ok);
     __ jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
     __ bind(ok);
     // Method might have been compiled since the call site was patched to
     // interpreted if that is the case treat it as a miss so we can get
     // the call site corrected.
     __ cmpq(Address(rbx, in_bytes(methodOopDesc::code_offset())), (int)NULL_WORD);
     __ jcc(Assembler::equal, skip_fixup);
     __ 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 new AdapterHandlerEntry(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.
 // NOTE: These arrays will have to change when c1 is ported
 #ifdef _WIN64
     static const Register INT_ArgReg[Argument::n_int_register_parameters_c] = {
       c_rarg0, c_rarg1, c_rarg2, c_rarg3
     };
     static const XMMRegister FP_ArgReg[Argument::n_float_register_parameters_c] = {
       c_farg0, c_farg1, c_farg2, c_farg3
     };
 #else
     static const Register INT_ArgReg[Argument::n_int_register_parameters_c] = {
       c_rarg0, c_rarg1, c_rarg2, c_rarg3, c_rarg4, c_rarg5
     };
     static const XMMRegister FP_ArgReg[Argument::n_float_register_parameters_c] = {
       c_farg0, c_farg1, c_farg2, c_farg3,
       c_farg4, c_farg5, c_farg6, c_farg7
     };
 #endif // _WIN64
     uint int_args = 0;
     uint fp_args = 0;
     uint stk_args = 0; // inc by 2 each time
     for (int i = 0; i < total_args_passed; i++) {
       switch (sig_bt[i]) {
       case T_BOOLEAN:
       case T_CHAR:
       case T_BYTE:
       case T_SHORT:
       case T_INT:
         if (int_args < Argument::n_int_register_parameters_c) {
           regs[i].set1(INT_ArgReg[int_args++]->as_VMReg());
 #ifdef _WIN64
           fp_args++;
           // Allocate slots for callee to stuff register args the stack.
           stk_args += 2;
 #endif
         } else {
           regs[i].set1(VMRegImpl::stack2reg(stk_args));
           stk_args += 2;
         }
         break;
       case T_LONG:
         assert(sig_bt[i + 1] == T_VOID, "expecting half");
         // fall through
       case T_OBJECT:
       case T_ARRAY:
       case T_ADDRESS:
         if (int_args < Argument::n_int_register_parameters_c) {
           regs[i].set2(INT_ArgReg[int_args++]->as_VMReg());
 #ifdef _WIN64
           fp_args++;
           stk_args += 2;
 #endif
         } else {
           regs[i].set2(VMRegImpl::stack2reg(stk_args));
           stk_args += 2;
         }
         break;
       case T_FLOAT:
         if (fp_args < Argument::n_float_register_parameters_c) {
           regs[i].set1(FP_ArgReg[fp_args++]->as_VMReg());
 #ifdef _WIN64
           int_args++;
           // Allocate slots for callee to stuff register args the stack.
           stk_args += 2;
 #endif
         } else {
           regs[i].set1(VMRegImpl::stack2reg(stk_args));
           stk_args += 2;
         }
         break;
       case T_DOUBLE:
         assert(sig_bt[i + 1] == T_VOID, "expecting half");
         if (fp_args < Argument::n_float_register_parameters_c) {
           regs[i].set2(FP_ArgReg[fp_args++]->as_VMReg());
 #ifdef _WIN64
           int_args++;
           // Allocate slots for callee to stuff register args the stack.
           stk_args += 2;
 #endif
         } else {
           regs[i].set2(VMRegImpl::stack2reg(stk_args));
           stk_args += 2;
         }
         break;
       case T_VOID: // Halves of longs and doubles
         assert(i != 0 && (sig_bt[i - 1] == T_LONG || sig_bt[i - 1] == T_DOUBLE), "expecting half");
         regs[i].set_bad();
         break;
       default:
         ShouldNotReachHere();
         break;
       }
     }
 #ifdef _WIN64
   // windows abi requires that we always allocate enough stack space
   // for 4 64bit registers to be stored down.
   if (stk_args < 8) {
     stk_args = 8;
   }
 #endif // _WIN64
   return stk_args;
 }
 // On 64 bit we will store integer like items to the stack as
 // 64 bits items (sparc abi) even though java would only store
 // 32bits for a parameter. On 32bit it will simply be 32 bits
 // So this routine will do 32->32 on 32bit and 32->64 on 64bit
 static void move32_64(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
   if (src.first()->is_stack()) {
     if (dst.first()->is_stack()) {
       // stack to stack
       __ movslq(rax, Address(rbp, reg2offset_in(src.first())));
       __ movq(Address(rsp, reg2offset_out(dst.first())), rax);
     } else {
       // stack to reg
       __ movslq(dst.first()->as_Register(), Address(rbp, reg2offset_in(src.first())));
     }
   } else if (dst.first()->is_stack()) {
     // reg to stack
     // Do we really have to sign extend???
     // __ movslq(src.first()->as_Register(), src.first()->as_Register());
     __ movq(Address(rsp, reg2offset_out(dst.first())), src.first()->as_Register());
   } else {
     // Do we really have to sign extend???
     // __ movslq(dst.first()->as_Register(), src.first()->as_Register());
     if (dst.first() != src.first()) {
       __ movq(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) {
   // must pass a handle. First figure out the location we use as a handle
   Register rHandle = dst.first()->is_stack() ? rax : dst.first()->as_Register();
   // See if oop is NULL if it is we need no handle
   if (src.first()->is_stack()) {
     // Oop is already on the stack as an argument
     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;
     }
     __ cmpq(Address(rbp, reg2offset_in(src.first())), (int)NULL_WORD);
     __ leaq(rHandle, Address(rbp, reg2offset_in(src.first())));
     // conditionally move a NULL
     __ cmovq(Assembler::equal, rHandle, Address(rbp, reg2offset_in(src.first())));
   } else {
     // Oop is in an a register we must store it to the space we reserve
     // on the stack for oop_handles and pass a handle if oop is non-NULL
     const Register rOop = src.first()->as_Register();
     int oop_slot;
     if (rOop == j_rarg0)
       oop_slot = 0;
     else if (rOop == j_rarg1)
       oop_slot = 1;
     else if (rOop == j_rarg2)
       oop_slot = 2;
     else if (rOop == j_rarg3)
       oop_slot = 3;
     else if (rOop == j_rarg4)
       oop_slot = 4;
     else {
       assert(rOop == j_rarg5, "wrong register");
       oop_slot = 5;
     }
     oop_slot = oop_slot * VMRegImpl::slots_per_word + oop_handle_offset;
     int offset = oop_slot*VMRegImpl::stack_slot_size;
     map->set_oop(VMRegImpl::stack2reg(oop_slot));
     // Store oop in handle area, may be NULL
     __ movq(Address(rsp, offset), rOop);
     if (is_receiver) {
       *receiver_offset = offset;
     }
     __ cmpq(rOop, (int)NULL);
     __ leaq(rHandle, Address(rsp, offset));
     // conditionally move a NULL from the handle area where it was just stored
     __ cmovq(Assembler::equal, rHandle, Address(rsp, offset));
   }
   // If arg is on the stack then place it otherwise it is already in correct reg.
   if (dst.first()->is_stack()) {
     __ movq(Address(rsp, reg2offset_out(dst.first())), rHandle);
   }
 }
 // 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");
   // The calling conventions assures us that each VMregpair is either
   // all really one physical register or adjacent stack slots.
   // This greatly simplifies the cases here compared to sparc.
   if (src.first()->is_stack()) {
     if (dst.first()->is_stack()) {
       __ movl(rax, Address(rbp, reg2offset_in(src.first())));
       __ movq(Address(rsp, reg2offset_out(dst.first())), rax);
     } else {
       // stack to reg
       assert(dst.first()->is_XMMRegister(), "only expect xmm registers as parameters");
       __ movflt(dst.first()->as_XMMRegister(), Address(rbp, reg2offset_in(src.first())));
     }
   } else if (dst.first()->is_stack()) {
     // reg to stack
     assert(src.first()->is_XMMRegister(), "only expect xmm registers as parameters");
     __ movflt(Address(rsp, reg2offset_out(dst.first())), src.first()->as_XMMRegister());
   } else {
     // reg to reg
     // In theory these overlap but the ordering is such that this is likely a nop
     if ( src.first() != dst.first()) {
       __ movdbl(dst.first()->as_XMMRegister(),  src.first()->as_XMMRegister());
     }
   }
 }
 // A long move
 static void long_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
   // The calling conventions assures us that each VMregpair is either
   // all really one physical register or adjacent stack slots.
   // This greatly simplifies the cases here compared to sparc.
   if (src.is_single_phys_reg() ) {
     if (dst.is_single_phys_reg()) {
       if (dst.first() != src.first()) {
         __ movq(dst.first()->as_Register(), src.first()->as_Register());
       }
     } else {
       assert(dst.is_single_reg(), "not a stack pair");
       __ movq(Address(rsp, reg2offset_out(dst.first())), src.first()->as_Register());
     }
   } else if (dst.is_single_phys_reg()) {
     assert(src.is_single_reg(),  "not a stack pair");
     __ movq(dst.first()->as_Register(), Address(rbp, reg2offset_out(src.first())));
   } else {
     assert(src.is_single_reg() && dst.is_single_reg(), "not stack pairs");
     __ movq(rax, Address(rbp, reg2offset_in(src.first())));
     __ movq(Address(rsp, reg2offset_out(dst.first())), rax);
   }
 }
 // A double move
 static void double_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
   // The calling conventions assures us that each VMregpair is either
   // all really one physical register or adjacent stack slots.
   // This greatly simplifies the cases here compared to sparc.
   if (src.is_single_phys_reg() ) {
     if (dst.is_single_phys_reg()) {
       // In theory these overlap but the ordering is such that this is likely a nop
       if ( src.first() != dst.first()) {
         __ movdbl(dst.first()->as_XMMRegister(), src.first()->as_XMMRegister());
       }
     } else {
       assert(dst.is_single_reg(), "not a stack pair");
       __ movdbl(Address(rsp, reg2offset_out(dst.first())), src.first()->as_XMMRegister());
     }
   } else if (dst.is_single_phys_reg()) {
     assert(src.is_single_reg(),  "not a stack pair");
     __ movdbl(dst.first()->as_XMMRegister(), Address(rbp, reg2offset_out(src.first())));
   } else {
     assert(src.is_single_reg() && dst.is_single_reg(), "not stack pairs");
     __ movq(rax, Address(rbp, reg2offset_in(src.first())));
     __ movq(Address(rsp, reg2offset_out(dst.first())), rax);
   }
 }
 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:
     __ movflt(Address(rbp, -wordSize), xmm0);
     break;
   case T_DOUBLE:
     __ movdbl(Address(rbp, -wordSize), xmm0);
     break;
   case T_VOID:  break;
   default: {
     __ movq(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:
     __ movflt(xmm0, Address(rbp, -wordSize));
     break;
   case T_DOUBLE:
     __ movdbl(xmm0, Address(rbp, -wordSize));
     break;
   case T_VOID:  break;
   default: {
     __ movq(rax, Address(rbp, -wordSize));
     }
   }
 }
 static void save_args(MacroAssembler *masm, int arg_count, int first_arg, VMRegPair *args) {
     for ( int i = first_arg ; i < arg_count ; i++ ) {
       if (args[i].first()->is_Register()) {
         __ pushq(args[i].first()->as_Register());
       } else if (args[i].first()->is_XMMRegister()) {
         __ subq(rsp, 2*wordSize);
         __ movdbl(Address(rsp, 0), args[i].first()->as_XMMRegister());
       }
     }
 }
 static void restore_args(MacroAssembler *masm, int arg_count, int first_arg, VMRegPair *args) {
     for ( int i = arg_count - 1 ; i >= first_arg ; i-- ) {
       if (args[i].first()->is_Register()) {
         __ popq(args[i].first()->as_Register());
       } else if (args[i].first()->is_XMMRegister()) {
         __ movdbl(args[i].first()->as_XMMRegister(), Address(rsp, 0));
         __ addq(rsp, 2*wordSize);
       }
     }
 }
 // ---------------------------------------------------------------------------
 // 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.
 nmethod *SharedRuntime::generate_native_wrapper(MacroAssembler *masm,
                                                 methodHandle method,
                                                 int total_in_args,
                                                 int comp_args_on_stack,
                                                 BasicType *in_sig_bt,
                                                 VMRegPair *in_regs,
                                                 BasicType ret_type) {
   // Native nmethod wrappers never take possesion of the oop arguments.
   // So the caller will gc the arguments. The only thing we need an
   // oopMap for is if the call is static
   //
   // An OopMap for lock (and class if static)
   OopMapSet *oop_maps = new OopMapSet();
   intptr_t start = (intptr_t)__ pc();
   // 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 + 1;
   if (method->is_static()) {
     total_c_args++;
   }
   BasicType* out_sig_bt = NEW_RESOURCE_ARRAY(BasicType, total_c_args);
   VMRegPair* out_regs   = NEW_RESOURCE_ARRAY(VMRegPair,   total_c_args);
   int argc = 0;
   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];
   }
   // 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
   // incoming registers
   // Calculate the total number of stack slots we will need.
   // First count the abi requirement plus all of the outgoing args
   int stack_slots = SharedRuntime::out_preserve_stack_slots() + out_arg_slots;
   // Now the space for the inbound oop handle area
   int oop_handle_offset = stack_slots;
   stack_slots += 6*VMRegImpl::slots_per_word;
   // Now any space we need for handlizing a klass if static method
   int oop_temp_slot_offset = 0;
   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
   // + 4 for return address (which we own) and saved rbp
   stack_slots += 6;
   // Ok The space we have allocated will look like:
   //
   //
   // FP-> |                     |
   //      |---------------------|
   //      | 2 slots for moves   |
   //      |---------------------|
   //      | lock box (if sync)  |
   //      |---------------------| <- lock_slot_offset
   //      | klass (if static)   |
   //      |---------------------| <- klass_slot_offset
   //      | oopHandle area      |
   //      |---------------------| <- oop_handle_offset (6 java arg registers)
   //      | 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, 4 * VMRegImpl::slots_per_word);
   int stack_size = stack_slots * VMRegImpl::stack_slot_size;
   // 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 = j_rarg0;
   Label ok;
   Label exception_pending;
   __ verify_oop(receiver);
   __ cmpq(ic_reg, Address(receiver, oopDesc::klass_offset_in_bytes()));
   __ jcc(Assembler::equal, ok);
   __ jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
   // Verified entry point must be aligned
   __ align(8);
   __ bind(ok);
   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) {
     __ 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
   __ subq(rsp, stack_size - 2*wordSize);
     // Frame is now completed as far as size and linkage.
     int frame_complete = ((intptr_t)__ pc()) - start;
 #ifdef ASSERT
     {
       Label L;
       __ movq(rax, rsp);
       __ andq(rax, -16); // must be 16 byte boundry (see amd64 ABI)
       __ cmpq(rax, rsp);
       __ jcc(Assembler::equal, L);
       __ stop("improperly aligned stack");
       __ bind(L);
     }
 #endif /* ASSERT */
   // We use r14 as the oop handle for the receiver/klass
   // It is callee save so it survives the call to native
   const Register oop_handle_reg = r14;
   //
   // 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
   // The Java calling convention is either equal (linux) or denser (win64) than the
   // c calling convention. However the because of the jni_env argument the c calling
   // convention always has at least one more (and two for static) arguments than Java.
   // Therefore if we move the args from java -> c backwards then we will never have
   // a register->register conflict and we don't have to build a dependency graph
   // and figure out how to break any cycles.
   //
   // Record esp-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 (someday)
   // map->set_callee_saved(VMRegImpl::stack2reg( stack_slots - 2), stack_slots * 2, 0, vmreg(rbp));
   // Use eax, ebx as temporaries during any memory-memory moves we have to do
   // All inbound args are referenced based on rbp and all outbound args via rsp.
 #ifdef ASSERT
   bool reg_destroyed[RegisterImpl::number_of_registers];
   bool freg_destroyed[XMMRegisterImpl::number_of_registers];
   for ( int r = 0 ; r < RegisterImpl::number_of_registers ; r++ ) {
     reg_destroyed[r] = false;
   }
   for ( int f = 0 ; f < XMMRegisterImpl::number_of_registers ; f++ ) {
     freg_destroyed[f] = false;
   }
 #endif /* ASSERT */
   int c_arg = total_c_args - 1;
   for ( int i = total_in_args - 1; i >= 0 ; i--, c_arg-- ) {
 #ifdef ASSERT
     if (in_regs[i].first()->is_Register()) {
       assert(!reg_destroyed[in_regs[i].first()->as_Register()->encoding()], "destroyed reg!");
     } else if (in_regs[i].first()->is_XMMRegister()) {
       assert(!freg_destroyed[in_regs[i].first()->as_XMMRegister()->encoding()], "destroyed reg!");
     }
     if (out_regs[c_arg].first()->is_Register()) {
       reg_destroyed[out_regs[c_arg].first()->as_Register()->encoding()] = true;
     } else if (out_regs[c_arg].first()->is_XMMRegister()) {
       freg_destroyed[out_regs[c_arg].first()->as_XMMRegister()->encoding()] = true;
     }
 #endif /* ASSERT */
     switch (in_sig_bt[i]) {
       case T_ARRAY:
       case T_OBJECT:
         object_move(masm, map, oop_handle_offset, stack_slots, in_regs[i], out_regs[c_arg],
                     ((i == 0) && (!is_static)),
                     &receiver_offset);
         break;
       case T_VOID:
         break;
       case T_FLOAT:
         float_move(masm, in_regs[i], out_regs[c_arg]);
           break;
       case T_DOUBLE:
         assert( i + 1 < total_in_args &&
                 in_sig_bt[i + 1] == T_VOID &&
                 out_sig_bt[c_arg+1] == T_VOID, "bad arg list");
         double_move(masm, in_regs[i], out_regs[c_arg]);
         break;
       case T_LONG :
         long_move(masm, in_regs[i], out_regs[c_arg]);
         break;
       case T_ADDRESS: assert(false, "found T_ADDRESS in java args");
       default:
         move32_64(masm, in_regs[i], out_regs[c_arg]);
     }
   }
   // point c_arg at the first arg that is already loaded in case we
   // need to spill before we call out
   c_arg++;
   // Pre-load a static method's oop into r14.  Used both by locking code and
   // the normal JNI call code.
   if (method->is_static()) {
     //  load oop 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.
     __ movq(Address(rsp, klass_offset), oop_handle_reg);
     map->set_oop(VMRegImpl::stack2reg(klass_slot_offset));
     // Now get the handle
     __ leaq(oop_handle_reg, Address(rsp, klass_offset));
     // store the klass handle as second argument
     __ movq(c_rarg1, oop_handle_reg);
     // and protect the arg if we must spill
     c_arg--;
   }
   // 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(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(masm, &DTraceMethodProbes, false);
     // protect the args we've loaded
     save_args(masm, total_c_args, c_arg, out_regs);
     __ movoop(c_rarg1, JNIHandles::make_local(method()));
     __ call_VM_leaf(
       CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_entry),
       r15_thread, c_rarg1);
     restore_args(masm, total_c_args, c_arg, out_regs);
   }
   // Lock a synchronized method
   // Register definitions used by locking and unlocking
   const Register swap_reg = rax;  // Must use rax for cmpxchg instruction
   const Register obj_reg  = rbx;  // Will contain the oop
   const Register lock_reg = r13;  // Address of compiler lock object (BasicLock)
   const Register old_hdr  = r13;  // value of old header at unlock time
   Label slow_path_lock;
   Label lock_done;
   if (method->is_synchronized()) {
     const int mark_word_offset = BasicLock::displaced_header_offset_in_bytes();
     // Get the handle (the 2nd argument)
     __ movq(oop_handle_reg, c_rarg1);
     // Get address of the box
     __ leaq(lock_reg, Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size));
     // Load the oop from the handle
     __ movq(obj_reg, Address(oop_handle_reg, 0));
     if (UseBiasedLocking) {
       __ biased_locking_enter(lock_reg, obj_reg, swap_reg, rscratch1, false, lock_done, &slow_path_lock);
     }
     // Load immediate 1 into swap_reg %rax
     __ movl(swap_reg, 1);
     // Load (object->mark() | 1) into swap_reg %rax
     __ orq(swap_reg, Address(obj_reg, 0));
     // Save (object->mark() | 1) into BasicLock's displaced header
     __ movq(Address(lock_reg, mark_word_offset), swap_reg);
     if (os::is_MP()) {
       __ lock();
     }
     // src -> dest iff dest == rax else rax <- dest
     __ cmpxchgq(lock_reg, Address(obj_reg, 0));
     __ jcc(Assembler::equal, lock_done);
     // Hmm should this move to the slow path code area???
     // 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
     __ subq(swap_reg, rsp);
     __ andq(swap_reg, 3 - os::vm_page_size());
     // Save the test result, for recursive case, the result is zero
     __ movq(Address(lock_reg, mark_word_offset), swap_reg);
     __ jcc(Assembler::notEqual, slow_path_lock);
     // Slow path will re-enter here
     __ bind(lock_done);
   }
   // Finally just about ready to make the JNI call
   // get JNIEnv* which is first argument to native
   __ leaq(c_rarg0, Address(r15_thread, in_bytes(JavaThread::jni_environment_offset())));
   // Now set thread in native
   __ mov64(Address(r15_thread, JavaThread::thread_state_offset()), _thread_in_native);
   __ call(RuntimeAddress(method->native_function()));
     // Either restore the MXCSR register after returning from the JNI Call
     // or verify that it wasn't changed.
     if (RestoreMXCSROnJNICalls) {
       __ ldmxcsr(ExternalAddress(StubRoutines::amd64::mxcsr_std()));
     }
     else if (CheckJNICalls ) {
       __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, StubRoutines::amd64::verify_mxcsr_entry())));
     }
   // Unpack native results.
   switch (ret_type) {
   case T_BOOLEAN: __ c2bool(rax);            break;
   case T_CHAR   : __ movzwl(rax, rax);      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 xmm0 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.
   __ mov64(Address(r15_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(r15_thread, rcx);
     }
   }
   // 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(r15_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);
     __ movq(c_rarg0, r15_thread);
     __ movq(r12, rsp); // remember sp
     __ subq(rsp, frame::arg_reg_save_area_bytes); // windows
     __ andq(rsp, -16); // align stack as required by ABI
     __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans)));
     __ movq(rsp, r12); // restore sp
     // Restore any method result value
     restore_native_result(masm, ret_type, stack_slots);
     __ bind(Continue);
   }
   // change thread state
   __ movl(Address(r15_thread, JavaThread::thread_state_offset()), _thread_in_Java);
   Label reguard;
   Label reguard_done;
   __ cmpl(Address(r15_thread, JavaThread::stack_guard_state_offset()), JavaThread::stack_guard_yellow_disabled);
   __ jcc(Assembler::equal, reguard);
   __ bind(reguard_done);
   // native result if any is live
   // Unlock
   Label unlock_done;
   Label slow_path_unlock;
   if (method->is_synchronized()) {
     // Get locked oop from the handle we passed to jni
     __ movq(obj_reg, Address(oop_handle_reg, 0));
     Label done;
     if (UseBiasedLocking) {
       __ biased_locking_exit(obj_reg, old_hdr, done);
     }
     // Simple recursive lock?
     __ cmpq(Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size), (int)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 address of the stack lock
     __ leaq(rax, Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size));
     //  get old displaced header
     __ movq(old_hdr, Address(rax, 0));
     // Atomic swap old header if oop still contains the stack lock
     if (os::is_MP()) {
       __ lock();
     }
     __ cmpxchgq(old_hdr, 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(masm, &DTraceMethodProbes, false);
     save_native_result(masm, ret_type, stack_slots);
     __ movoop(c_rarg1, JNIHandles::make_local(method()));
     __ call_VM_leaf(
          CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_exit),
          r15_thread, c_rarg1);
     restore_native_result(masm, ret_type, stack_slots);
   }
   __ reset_last_Java_frame(false, true);
   // Unpack oop result
   if (ret_type == T_OBJECT || ret_type == T_ARRAY) {
       Label L;
       __ testq(rax, rax);
       __ jcc(Assembler::zero, L);
       __ movq(rax, Address(rax, 0));
       __ bind(L);
       __ verify_oop(rax);
   }
   // reset handle block
   __ movq(rcx, Address(r15_thread, JavaThread::active_handles_offset()));
   __ movptr(Address(rcx, JNIHandleBlock::top_offset_in_bytes()), (int)NULL_WORD);
   // pop our frame
   __ leave();
   // Any exception pending?
   __ cmpq(Address(r15_thread, in_bytes(Thread::pending_exception_offset())), (int)NULL_WORD);
   __ jcc(Assembler::notEqual, exception_pending);
   // Return
   __ ret(0);
   // Unexpected paths are out of line and go here
   // forward the exception
   __ bind(exception_pending);
   // and forward the exception
   __ jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
   // 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)
     // protect the args we've loaded
     save_args(masm, total_c_args, c_arg, out_regs);
     __ movq(c_rarg0, obj_reg);
     __ movq(c_rarg1, lock_reg);
     __ movq(c_rarg2, r15_thread);
     // Not a leaf but we have last_Java_frame setup as we want
     __ call_VM_leaf(CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_locking_C), 3);
     restore_args(masm, total_c_args, c_arg, out_regs);
 #ifdef ASSERT
     { Label L;
     __ cmpq(Address(r15_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);
     // If we haven't already saved the native result we must save it now as xmm registers
     // are still exposed.
     if (ret_type == T_FLOAT || ret_type == T_DOUBLE ) {
       save_native_result(masm, ret_type, stack_slots);
     }
     __ leaq(c_rarg1, Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size));
     __ movq(c_rarg0, obj_reg);
     __ movq(r12, rsp); // remember sp
     __ subq(rsp, frame::arg_reg_save_area_bytes); // windows
     __ andq(rsp, -16); // align stack as required by ABI
     // Save pending exception around call to VM (which contains an EXCEPTION_MARK)
     // NOTE that obj_reg == rbx currently
     __ movq(rbx, Address(r15_thread, in_bytes(Thread::pending_exception_offset())));
     __ movptr(Address(r15_thread, in_bytes(Thread::pending_exception_offset())), (int)NULL_WORD);
     __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C)));
     __ movq(rsp, r12); // restore sp
 #ifdef ASSERT
     {
       Label L;
       __ cmpq(Address(r15_thread, in_bytes(Thread::pending_exception_offset())), (int)NULL_WORD);
       __ jcc(Assembler::equal, L);
       __ stop("no pending exception allowed on exit complete_monitor_unlocking_C");
       __ bind(L);
     }
 #endif /* ASSERT */
     __ movq(Address(r15_thread, in_bytes(Thread::pending_exception_offset())), rbx);
     if (ret_type == T_FLOAT || ret_type == T_DOUBLE ) {
       restore_native_result(masm, ret_type, stack_slots);
     }
     __ jmp(unlock_done);
     // END Slow path unlock
   } // synchronized
   // SLOW PATH Reguard the stack if needed
   __ bind(reguard);
   save_native_result(masm, ret_type, stack_slots);
   __ movq(r12, rsp); // remember sp
   __ subq(rsp, frame::arg_reg_save_area_bytes); // windows
   __ andq(rsp, -16); // align stack as required by ABI
   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::reguard_yellow_pages)));
   __ movq(rsp, r12); // restore sp
   restore_native_result(masm, ret_type, stack_slots);
   // and continue
   __ jmp(reguard_done);
   __ flush();
   nmethod *nm = nmethod::new_native_nmethod(method,
                                             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);
   return nm;
 }
 // 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", 2048, 1024);
   MacroAssembler* masm = new MacroAssembler(&buffer);
   int frame_size_in_words;
   OopMap* map = NULL;
   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 so it looks like we have the original return
   // address on the stack (like when we eagerly deoptimized).
   // In the case of an exception pending when deoptimizing, 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 from,
   // e.g., the forward exception stub (see stubGenerator_x86_64.cpp).
   //    rax: exception oop
   //    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, 0, &frame_size_in_words);
   // Normal deoptimization.  Save exec mode for unpack_frames.
   __ movl(r12, Deoptimization::Unpack_deopt); // callee-saved
   __ jmp(cont);
   int exception_offset = __ pc() - start;
   // Prolog for exception case
   // Push throwing pc as return address
   __ pushq(rdx);
   // Save everything in sight.
   map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
   // Deopt during an exception.  Save exec mode for unpack_frames.
   __ movl(r12, Deoptimization::Unpack_exception); // callee-saved
   __ bind(cont);
   // Call C code.  Need thread and this frame, but NOT official VM entry
   // crud.  We cannot block on this call, no GC can happen.
   //
   // UnrollBlock* fetch_unroll_info(JavaThread* thread)
   // fetch_unroll_info needs to call last_java_frame().
   __ set_last_Java_frame(noreg, noreg, NULL);
 #ifdef ASSERT
   { Label L;
     __ cmpq(Address(r15_thread,
                     JavaThread::last_Java_fp_offset()),
 );
     __ jcc(Assembler::equal, L);
     __ stop("SharedRuntime::generate_deopt_blob: last_Java_fp not cleared");
     __ bind(L);
   }
 #endif // ASSERT
   __ movq(c_rarg0, r15_thread);
   __ 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);
   __ reset_last_Java_frame(false, false);
   // Load UnrollBlock* into rdi
   __ movq(rdi, rax);
   // Only register save data is on the stack.
   // Now restore the result registers.  Everything else is either dead
   // or captured in the vframeArray.
   RegisterSaver::restore_result_registers(masm);
   // 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
   __ movl(rcx, Address(rdi, Deoptimization::UnrollBlock::size_of_deoptimized_frame_offset_in_bytes()));
   __ addq(rsp, rcx);
   // rsp 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 address of array of frame pcs into rcx
   __ movq(rcx, Address(rdi, Deoptimization::UnrollBlock::frame_pcs_offset_in_bytes()));
   // Trash the old pc
   __ addq(rsp, wordSize);
   // Load address of array of frame sizes into rsi
   __ movq(rsi, Address(rdi, Deoptimization::UnrollBlock::frame_sizes_offset_in_bytes()));
   // Load counter into rdx
   __ movl(rdx, Address(rdi, Deoptimization::UnrollBlock::number_of_frames_offset_in_bytes()));
   // Pick up the initial fp we should save
   __ movq(rbp, Address(rdi, Deoptimization::UnrollBlock::initial_fp_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.
   const Register sender_sp = r8;
   __ movq(sender_sp, rsp);
   __ movl(rbx, Address(rdi,
                        Deoptimization::UnrollBlock::
                        caller_adjustment_offset_in_bytes()));
   __ subq(rsp, rbx);
   // Push interpreter frames in a loop
   Label loop;
   __ bind(loop);
   __ movq(rbx, Address(rsi, 0));        // Load frame size
   __ subq(rbx, 2*wordSize);             // We'll push pc and ebp by hand
   __ pushq(Address(rcx, 0));            // Save return address
   __ enter();                           // Save old & set new ebp
   __ subq(rsp, rbx);                    // Prolog
   __ movq(Address(rbp, frame::interpreter_frame_sender_sp_offset * wordSize),
           sender_sp);                   // Make it walkable
   // This value is corrected by layout_activation_impl
   __ movptr(Address(rbp, frame::interpreter_frame_last_sp_offset * wordSize), (int)NULL_WORD );
   __ movq(sender_sp, rsp);              // Pass sender_sp to next frame
   __ addq(rsi, wordSize);               // Bump array pointer (sizes)
   __ addq(rcx, wordSize);               // Bump array pointer (pcs)
   __ decrementl(rdx);                   // Decrement counter
   __ jcc(Assembler::notZero, loop);
   __ pushq(Address(rcx, 0));            // Save final return address
   // Re-push self-frame
   __ enter();                           // Save old & set new ebp
   // Allocate a full sized register save area.
   // Return address and rbp are in place, so we allocate two less words.
   __ subq(rsp, (frame_size_in_words - 2) * wordSize);
   // Restore frame locals after moving the frame
   __ movdbl(Address(rsp, RegisterSaver::xmm0_offset_in_bytes()), xmm0);
   __ movq(Address(rsp, RegisterSaver::rax_offset_in_bytes()), rax);
   // 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.
   //
   // void Deoptimization::unpack_frames(JavaThread* thread, int exec_mode)
   // Use rbp because the frames look interpreted now
   __ set_last_Java_frame(noreg, rbp, NULL);
   __ movq(c_rarg0, r15_thread);
   __ movl(c_rarg1, r12); // second arg: exec_mode
   __ 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 ));
   __ reset_last_Java_frame(true, false);
   // Collect return values
   __ movdbl(xmm0, Address(rsp, RegisterSaver::xmm0_offset_in_bytes()));
   __ movq(rax, Address(rsp, RegisterSaver::rax_offset_in_bytes()));
   // 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, 0, frame_size_in_words);
 }
 #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", 2048, 1024);
   MacroAssembler* masm = new MacroAssembler(&buffer);
   assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
   address start = __ pc();
   // Push self-frame.  We get here with a return address on the
   // stack, so rsp is 8-byte aligned until we allocate our frame.
   __ subq(rsp, SimpleRuntimeFrame::return_off << LogBytesPerInt); // Epilog!
   // No callee saved registers. rbp is assumed implicitly saved
   __ movq(Address(rsp, SimpleRuntimeFrame::rbp_off << LogBytesPerInt), rbp);
   // compiler left unloaded_class_index in j_rarg0 move to where the
   // runtime expects it.
   __ movl(c_rarg1, j_rarg0);
   __ set_last_Java_frame(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.
   // Thread is in rdi already.
   //
   // UnrollBlock* uncommon_trap(JavaThread* thread, jint unloaded_class_index);
   __ movq(c_rarg0, r15_thread);
   __ 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(SimpleRuntimeFrame::framesize, 0);
   // location of rbp is known implicitly by the frame sender code
   oop_maps->add_gc_map(__ pc() - start, map);
   __ reset_last_Java_frame(false, false);
   // Load UnrollBlock* into rdi
   __ movq(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 rax and rsp.
   __ addq(rsp, (SimpleRuntimeFrame::framesize - 2) << LogBytesPerInt); // Epilog!
   // Pop deoptimized frame (int)
   __ movl(rcx, Address(rdi,
                        Deoptimization::UnrollBlock::
                        size_of_deoptimized_frame_offset_in_bytes()));
   __ addq(rsp, rcx);
   // rsp 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 address of array of frame pcs into rcx (address*)
   __ movq(rcx,
           Address(rdi,
                   Deoptimization::UnrollBlock::frame_pcs_offset_in_bytes()));
   // Trash the return pc
   __ addq(rsp, wordSize);
   // Load address of array of frame sizes into rsi (intptr_t*)
   __ movq(rsi, Address(rdi,
                        Deoptimization::UnrollBlock::
                        frame_sizes_offset_in_bytes()));
   // Counter
   __ movl(rdx, Address(rdi,
                        Deoptimization::UnrollBlock::
                        number_of_frames_offset_in_bytes())); // (int)
   // Pick up the initial fp we should save
   __ movq(rbp,
           Address(rdi,
                   Deoptimization::UnrollBlock::initial_fp_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.
   const Register sender_sp = r8;
   __ movq(sender_sp, rsp);
   __ movl(rbx, Address(rdi,
                        Deoptimization::UnrollBlock::
                        caller_adjustment_offset_in_bytes())); // (int)
   __ subq(rsp, rbx);
   // Push interpreter frames in a loop
   Label loop;
   __ bind(loop);
   __ movq(rbx, Address(rsi, 0)); // Load frame size
   __ subq(rbx, 2 * wordSize); // We'll push pc and rbp by hand
   __ pushq(Address(rcx, 0));  // Save return address
   __ enter();                 // Save old & set new rbp
   __ subq(rsp, rbx);          // Prolog
   __ movq(Address(rbp, frame::interpreter_frame_sender_sp_offset * wordSize),
           sender_sp);         // Make it walkable
   // This value is corrected by layout_activation_impl
   __ movptr(Address(rbp, frame::interpreter_frame_last_sp_offset * wordSize), (int)NULL_WORD );
   __ movq(sender_sp, rsp);    // Pass sender_sp to next frame
   __ addq(rsi, wordSize);     // Bump array pointer (sizes)
   __ addq(rcx, wordSize);     // Bump array pointer (pcs)
   __ decrementl(rdx);         // Decrement counter
   __ jcc(Assembler::notZero, loop);
   __ pushq(Address(rcx, 0)); // Save final return address
   // Re-push self-frame
   __ enter();                 // Save old & set new rbp
   __ subq(rsp, (SimpleRuntimeFrame::framesize - 4) << LogBytesPerInt);
                               // Prolog
   // Use rbp because the frames look interpreted now
   __ set_last_Java_frame(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.
   // Thread is in rdi already.
   //
   // BasicType unpack_frames(JavaThread* thread, int exec_mode);
   __ movq(c_rarg0, r15_thread);
   __ movl(c_rarg1, 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(SimpleRuntimeFrame::framesize, 0));
   __ reset_last_Java_frame(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,
                                                  SimpleRuntimeFrame::framesize >> 1);
 }
 #endif // COMPILER2
 //------------------------------generate_handler_blob------
 //
 // Generate a special Compile2Runtime blob that saves all registers,
 // and setup oopmap.
 //
 static SafepointBlob* generate_handler_blob(address call_ptr, bool cause_return) {
   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", 2048, 1024);
   MacroAssembler* masm = new MacroAssembler(&buffer);
   address start   = __ pc();
   address call_pc = NULL;
   int frame_size_in_words;
   // Make room for return address (or push it again)
   if (!cause_return) {
     __ pushq(rbx);
   }
   // Save registers, fpu state, and flags
   map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
   // 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 outselves.
   __ set_last_Java_frame(noreg, noreg, NULL);
   // The return address must always be correct so that frame constructor never
   // sees an invalid pc.
   if (!cause_return) {
     // overwrite the dummy value we pushed on entry
     __ movq(c_rarg0, Address(r15_thread, JavaThread::saved_exception_pc_offset()));
     __ movq(Address(rbp, wordSize), c_rarg0);
   }
   // Do the call
   __ movq(c_rarg0, r15_thread);
   __ 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);
   Label noException;
   __ reset_last_Java_frame(false, false);
   __ cmpq(Address(r15_thread, Thread::pending_exception_offset()), (int)NULL_WORD);
   __ jcc(Assembler::equal, noException);
   // Exception pending
   RegisterSaver::restore_live_registers(masm);
   __ jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
   // No exception case
   __ bind(noException);
   // Normal exit, restore registers 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.
 //
 static RuntimeStub* 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_in_words;
   OopMapSet *oop_maps = new OopMapSet();
   OopMap* map = NULL;
   int start = __ offset();
   map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
   int frame_complete = __ offset();
   __ set_last_Java_frame(noreg, noreg, NULL);
   __ movq(c_rarg0, r15_thread);
   __ 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
   // clear last_Java_sp
   __ reset_last_Java_frame(false, false);
   // check for pending exceptions
   Label pending;
   __ cmpq(Address(r15_thread, Thread::pending_exception_offset()), (int)NULL_WORD);
   __ jcc(Assembler::notEqual, pending);
   // get the returned methodOop
   __ movq(rbx, Address(r15_thread, JavaThread::vm_result_offset()));
   __ movq(Address(rsp, RegisterSaver::rbx_offset_in_bytes()), rbx);
   __ movq(Address(rsp, RegisterSaver::rax_offset_in_bytes()), 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
   __ movptr(Address(r15_thread, JavaThread::vm_result_offset()), (int)NULL_WORD);
   __ movq(rax, Address(r15_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_in_words, oop_maps, true);
 }
 void SharedRuntime::generate_stubs() {
   _wrong_method_blob = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::handle_wrong_method),
                                         "wrong_method_stub");
   _ic_miss_blob =      generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::handle_wrong_method_ic_miss),
                                         "ic_miss_stub");
   _resolve_opt_virtual_call_blob = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::resolve_opt_virtual_call_C),
                                         "resolve_opt_virtual_call");
   _resolve_virtual_call_blob = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::resolve_virtual_call_C),
                                         "resolve_virtual_call");
   _resolve_static_call_blob = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::resolve_static_call_C),
                                         "resolve_static_call");
   _polling_page_safepoint_handler_blob =
     generate_handler_blob(CAST_FROM_FN_PTR(address,
                    SafepointSynchronize::handle_polling_page_exception), false);
   _polling_page_return_handler_blob =
     generate_handler_blob(CAST_FROM_FN_PTR(address,
                    SafepointSynchronize::handle_polling_page_exception), true);
   generate_deopt_blob();
 #ifdef COMPILER2
   generate_uncommon_trap_blob();
 #endif // COMPILER2
 }
 #ifdef COMPILER2
 // This is here instead of runtime_x86_64.cpp because it uses SimpleRuntimeFrame
 //
 //------------------------------generate_exception_blob---------------------------
 // creates exception blob at the end
 // Using exception blob, this code is jumped from a compiled method.
 // (see emit_exception_handler in x86_64.ad file)
 //
 // Given an exception pc at a call we call into the runtime for the
 // handler in this method. This handler might merely restore state
 // (i.e. callee save registers) unwind the frame and jump to the
 // exception handler for the nmethod if there is no Java level handler
 // for the nmethod.
 //
 // This code is entered with a jmp.
 //
 // Arguments:
 //   rax: exception oop
 //   rdx: exception pc
 //
 // Results:
 //   rax: exception oop
 //   rdx: exception pc in caller or ???
 //   destination: exception handler of caller
 //
 // Note: the exception pc MUST be at a call (precise debug information)
 //       Registers rax, rdx, rcx, rsi, rdi, r8-r11 are not callee saved.
 //
 void OptoRuntime::generate_exception_blob() {
   assert(!OptoRuntime::is_callee_saved_register(RDX_num), "");
   assert(!OptoRuntime::is_callee_saved_register(RAX_num), "");
   assert(!OptoRuntime::is_callee_saved_register(RCX_num), "");
   assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
   // Allocate space for the code
   ResourceMark rm;
   // Setup code generation tools
   CodeBuffer buffer("exception_blob", 2048, 1024);
   MacroAssembler* masm = new MacroAssembler(&buffer);
   address start = __ pc();
   // Exception pc is 'return address' for stack walker
   __ pushq(rdx);
   __ subq(rsp, SimpleRuntimeFrame::return_off << LogBytesPerInt); // Prolog
   // Save callee-saved registers.  See x86_64.ad.
   // 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 now that adapter frames are gone.
   __ movq(Address(rsp, SimpleRuntimeFrame::rbp_off << LogBytesPerInt), rbp);
   // Store exception in Thread object. We cannot pass any arguments to the
   // handle_exception call, since we do not want to make any assumption
   // about the size of the frame where the exception happened in.
   // c_rarg0 is either rdi (Linux) or rcx (Windows).
   __ movq(Address(r15_thread, JavaThread::exception_oop_offset()),rax);
   __ movq(Address(r15_thread, JavaThread::exception_pc_offset()), rdx);
   // This call does all the hard work.  It checks if an exception handler
   // exists in the method.
   // If so, it returns the handler address.
   // If not, it prepares for stack-unwinding, restoring the callee-save
   // registers of the frame being removed.
   //
   // address OptoRuntime::handle_exception_C(JavaThread* thread)
   __ set_last_Java_frame(noreg, noreg, NULL);
   __ movq(c_rarg0, r15_thread);
   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, OptoRuntime::handle_exception_C)));
   // Set an oopmap for the call site.  This oopmap will only be used if we
   // are unwinding the stack.  Hence, all locations will be dead.
   // Callee-saved registers will be the same as the frame above (i.e.,
   // handle_exception_stub), since they were restored when we got the
   // exception.
   OopMapSet* oop_maps = new OopMapSet();
   oop_maps->add_gc_map( __ pc()-start, new OopMap(SimpleRuntimeFrame::framesize, 0));
   __ reset_last_Java_frame(false, false);
   // Restore callee-saved registers
   // 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.
   __ movq(rbp, Address(rsp, SimpleRuntimeFrame::rbp_off << LogBytesPerInt));
   __ addq(rsp, SimpleRuntimeFrame::return_off << LogBytesPerInt); // Epilog
   __ popq(rdx);                  // No need for exception pc anymore
   // rax: exception handler
   // We have a handler in rax (could be deopt blob).
   __ movq(r8, rax);
   // Get the exception oop
   __ movq(rax, Address(r15_thread, JavaThread::exception_oop_offset()));
   // Get the exception pc in case we are deoptimized
   __ movq(rdx, Address(r15_thread, JavaThread::exception_pc_offset()));
 #ifdef ASSERT
   __ movptr(Address(r15_thread, JavaThread::exception_handler_pc_offset()), (int)NULL_WORD);
   __ movptr(Address(r15_thread, JavaThread::exception_pc_offset()), (int)NULL_WORD);
 #endif
   // Clear the exception oop so GC no longer processes it as a root.
   __ movptr(Address(r15_thread, JavaThread::exception_oop_offset()), (int)NULL_WORD);
   // rax: exception oop
   // r8:  exception handler
   // rdx: exception pc
   // Jump to handler
   __ jmp(r8);
   // Make sure all code is generated
   masm->flush();
   // Set exception blob
   _exception_blob =  ExceptionBlob::create(&buffer, oop_maps, SimpleRuntimeFrame::framesize >> 1);
 }
 #endif // COMPILER2

Mercurial > jdk8-mips64-public > hotspot / annotate

src/cpu/x86/vm/sharedRuntime_x86_64.cpp@a49a647afe9a (annotated)

src/cpu/x86/vm/sharedRuntime_x86_64.cpp