1 /*
   2  * Copyright (c) 2003, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #ifndef _WINDOWS
  27 #include "alloca.h"
  28 #endif
  29 #include "asm/macroAssembler.hpp"
  30 #include "asm/macroAssembler.inline.hpp"
  31 #include "code/debugInfoRec.hpp"
  32 #include "code/icBuffer.hpp"
  33 #include "code/nativeInst.hpp"
  34 #include "code/vtableStubs.hpp"
  35 #include "gc/shared/gcLocker.hpp"
  36 #include "interpreter/interpreter.hpp"
  37 #include "logging/log.hpp"
  38 #include "memory/resourceArea.hpp"
  39 #include "oops/compiledICHolder.hpp"
  40 #include "runtime/safepointMechanism.hpp"
  41 #include "runtime/sharedRuntime.hpp"
  42 #include "runtime/vframeArray.hpp"
  43 #include "utilities/align.hpp"
  44 #include "utilities/formatBuffer.hpp"
  45 #include "vm_version_x86.hpp"
  46 #include "vmreg_x86.inline.hpp"
  47 #ifdef COMPILER1
  48 #include "c1/c1_Runtime1.hpp"
  49 #endif
  50 #ifdef COMPILER2
  51 #include "opto/runtime.hpp"
  52 #endif
  53 #if INCLUDE_JVMCI
  54 #include "jvmci/jvmciJavaClasses.hpp"
  55 #endif
  56 
  57 #define __ masm->
  58 
  59 const int StackAlignmentInSlots = StackAlignmentInBytes / VMRegImpl::stack_slot_size;
  60 
  61 class SimpleRuntimeFrame {
  62 
  63   public:
  64 
  65   // Most of the runtime stubs have this simple frame layout.
  66   // This class exists to make the layout shared in one place.
  67   // Offsets are for compiler stack slots, which are jints.
  68   enum layout {
  69     // The frame sender code expects that rbp will be in the "natural" place and
  70     // will override any oopMap setting for it. We must therefore force the layout
  71     // so that it agrees with the frame sender code.
  72     rbp_off = frame::arg_reg_save_area_bytes/BytesPerInt,
  73     rbp_off2,
  74     return_off, return_off2,
  75     framesize
  76   };
  77 };
  78 
  79 class RegisterSaver {
  80   // Capture info about frame layout.  Layout offsets are in jint
  81   // units because compiler frame slots are jints.
  82 #define XSAVE_AREA_BEGIN 160
  83 #define XSAVE_AREA_YMM_BEGIN 576
  84 #define XSAVE_AREA_ZMM_BEGIN 1152
  85 #define XSAVE_AREA_UPPERBANK 1664
  86 #define DEF_XMM_OFFS(regnum) xmm ## regnum ## _off = xmm_off + (regnum)*16/BytesPerInt, xmm ## regnum ## H_off
  87 #define DEF_YMM_OFFS(regnum) ymm ## regnum ## _off = ymm_off + (regnum)*16/BytesPerInt, ymm ## regnum ## H_off
  88 #define DEF_ZMM_OFFS(regnum) zmm ## regnum ## _off = zmm_off + (regnum-16)*64/BytesPerInt, zmm ## regnum ## H_off
  89   enum layout {
  90     fpu_state_off = frame::arg_reg_save_area_bytes/BytesPerInt, // fxsave save area
  91     xmm_off       = fpu_state_off + XSAVE_AREA_BEGIN/BytesPerInt,            // offset in fxsave save area
  92     DEF_XMM_OFFS(0),
  93     DEF_XMM_OFFS(1),
  94     // 2..15 are implied in range usage
  95     ymm_off = xmm_off + (XSAVE_AREA_YMM_BEGIN - XSAVE_AREA_BEGIN)/BytesPerInt,
  96     DEF_YMM_OFFS(0),
  97     DEF_YMM_OFFS(1),
  98     // 2..15 are implied in range usage
  99     zmm_high = xmm_off + (XSAVE_AREA_ZMM_BEGIN - XSAVE_AREA_BEGIN)/BytesPerInt,
 100     zmm_off = xmm_off + (XSAVE_AREA_UPPERBANK - XSAVE_AREA_BEGIN)/BytesPerInt,
 101     DEF_ZMM_OFFS(16),
 102     DEF_ZMM_OFFS(17),
 103     // 18..31 are implied in range usage
 104     fpu_state_end = fpu_state_off + ((FPUStateSizeInWords-1)*wordSize / BytesPerInt),
 105     fpu_stateH_end,
 106     r15_off, r15H_off,
 107     r14_off, r14H_off,
 108     r13_off, r13H_off,
 109     r12_off, r12H_off,
 110     r11_off, r11H_off,
 111     r10_off, r10H_off,
 112     r9_off,  r9H_off,
 113     r8_off,  r8H_off,
 114     rdi_off, rdiH_off,
 115     rsi_off, rsiH_off,
 116     ignore_off, ignoreH_off,  // extra copy of rbp
 117     rsp_off, rspH_off,
 118     rbx_off, rbxH_off,
 119     rdx_off, rdxH_off,
 120     rcx_off, rcxH_off,
 121     rax_off, raxH_off,
 122     // 16-byte stack alignment fill word: see MacroAssembler::push/pop_IU_state
 123     align_off, alignH_off,
 124     flags_off, flagsH_off,
 125     // The frame sender code expects that rbp will be in the "natural" place and
 126     // will override any oopMap setting for it. We must therefore force the layout
 127     // so that it agrees with the frame sender code.
 128     rbp_off, rbpH_off,        // copy of rbp we will restore
 129     return_off, returnH_off,  // slot for return address
 130     reg_save_size             // size in compiler stack slots
 131   };
 132 
 133  public:
 134   static OopMap* save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words, bool save_vectors = false);
 135   static void restore_live_registers(MacroAssembler* masm, bool restore_vectors = false);
 136 
 137   // Offsets into the register save area
 138   // Used by deoptimization when it is managing result register
 139   // values on its own
 140 
 141   static int rax_offset_in_bytes(void)    { return BytesPerInt * rax_off; }
 142   static int rdx_offset_in_bytes(void)    { return BytesPerInt * rdx_off; }
 143   static int rbx_offset_in_bytes(void)    { return BytesPerInt * rbx_off; }
 144   static int xmm0_offset_in_bytes(void)   { return BytesPerInt * xmm0_off; }
 145   static int return_offset_in_bytes(void) { return BytesPerInt * return_off; }
 146 
 147   // During deoptimization only the result registers need to be restored,
 148   // all the other values have already been extracted.
 149   static void restore_result_registers(MacroAssembler* masm);
 150 };
 151 
 152 OopMap* RegisterSaver::save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words, bool save_vectors) {
 153   int off = 0;
 154   int num_xmm_regs = XMMRegisterImpl::number_of_registers;
 155   if (UseAVX < 3) {
 156     num_xmm_regs = num_xmm_regs/2;
 157   }
 158 #if COMPILER2_OR_JVMCI
 159   if (save_vectors) {
 160     assert(UseAVX > 0, "Vectors larger than 16 byte long are supported only with AVX");
 161     assert(MaxVectorSize <= 64, "Only up to 64 byte long vectors are supported");
 162   }
 163 #else
 164   assert(!save_vectors, "vectors are generated only by C2 and JVMCI");
 165 #endif
 166 
 167   // Always make the frame size 16-byte aligned, both vector and non vector stacks are always allocated
 168   int frame_size_in_bytes = align_up(reg_save_size*BytesPerInt, num_xmm_regs);
 169   // OopMap frame size is in compiler stack slots (jint's) not bytes or words
 170   int frame_size_in_slots = frame_size_in_bytes / BytesPerInt;
 171   // CodeBlob frame size is in words.
 172   int frame_size_in_words = frame_size_in_bytes / wordSize;
 173   *total_frame_words = frame_size_in_words;
 174 
 175   // Save registers, fpu state, and flags.
 176   // We assume caller has already pushed the return address onto the
 177   // stack, so rsp is 8-byte aligned here.
 178   // We push rpb twice in this sequence because we want the real rbp
 179   // to be under the return like a normal enter.
 180 
 181   __ enter();          // rsp becomes 16-byte aligned here
 182   __ push_CPU_state(); // Push a multiple of 16 bytes
 183 
 184   // push cpu state handles this on EVEX enabled targets
 185   if (save_vectors) {
 186     // Save upper half of YMM registers(0..15)
 187     int base_addr = XSAVE_AREA_YMM_BEGIN;
 188     for (int n = 0; n < 16; n++) {
 189       __ vextractf128_high(Address(rsp, base_addr+n*16), as_XMMRegister(n));
 190     }
 191     if (VM_Version::supports_evex()) {
 192       // Save upper half of ZMM registers(0..15)
 193       base_addr = XSAVE_AREA_ZMM_BEGIN;
 194       for (int n = 0; n < 16; n++) {
 195         __ vextractf64x4_high(Address(rsp, base_addr+n*32), as_XMMRegister(n));
 196       }
 197       // Save full ZMM registers(16..num_xmm_regs)
 198       base_addr = XSAVE_AREA_UPPERBANK;
 199       off = 0;
 200       int vector_len = Assembler::AVX_512bit;
 201       for (int n = 16; n < num_xmm_regs; n++) {
 202         __ evmovdqul(Address(rsp, base_addr+(off++*64)), as_XMMRegister(n), vector_len);
 203       }
 204     }
 205   } else {
 206     if (VM_Version::supports_evex()) {
 207       // Save upper bank of ZMM registers(16..31) for double/float usage
 208       int base_addr = XSAVE_AREA_UPPERBANK;
 209       off = 0;
 210       for (int n = 16; n < num_xmm_regs; n++) {
 211         __ movsd(Address(rsp, base_addr+(off++*64)), as_XMMRegister(n));
 212       }
 213     }
 214   }
 215   __ vzeroupper();
 216   if (frame::arg_reg_save_area_bytes != 0) {
 217     // Allocate argument register save area
 218     __ subptr(rsp, frame::arg_reg_save_area_bytes);
 219   }
 220 
 221   // Set an oopmap for the call site.  This oopmap will map all
 222   // oop-registers and debug-info registers as callee-saved.  This
 223   // will allow deoptimization at this safepoint to find all possible
 224   // debug-info recordings, as well as let GC find all oops.
 225 
 226   OopMapSet *oop_maps = new OopMapSet();
 227   OopMap* map = new OopMap(frame_size_in_slots, 0);
 228 
 229 #define STACK_OFFSET(x) VMRegImpl::stack2reg((x))
 230 
 231   map->set_callee_saved(STACK_OFFSET( rax_off ), rax->as_VMReg());
 232   map->set_callee_saved(STACK_OFFSET( rcx_off ), rcx->as_VMReg());
 233   map->set_callee_saved(STACK_OFFSET( rdx_off ), rdx->as_VMReg());
 234   map->set_callee_saved(STACK_OFFSET( rbx_off ), rbx->as_VMReg());
 235   // rbp location is known implicitly by the frame sender code, needs no oopmap
 236   // and the location where rbp was saved by is ignored
 237   map->set_callee_saved(STACK_OFFSET( rsi_off ), rsi->as_VMReg());
 238   map->set_callee_saved(STACK_OFFSET( rdi_off ), rdi->as_VMReg());
 239   map->set_callee_saved(STACK_OFFSET( r8_off  ), r8->as_VMReg());
 240   map->set_callee_saved(STACK_OFFSET( r9_off  ), r9->as_VMReg());
 241   map->set_callee_saved(STACK_OFFSET( r10_off ), r10->as_VMReg());
 242   map->set_callee_saved(STACK_OFFSET( r11_off ), r11->as_VMReg());
 243   map->set_callee_saved(STACK_OFFSET( r12_off ), r12->as_VMReg());
 244   map->set_callee_saved(STACK_OFFSET( r13_off ), r13->as_VMReg());
 245   map->set_callee_saved(STACK_OFFSET( r14_off ), r14->as_VMReg());
 246   map->set_callee_saved(STACK_OFFSET( r15_off ), r15->as_VMReg());
 247   // For both AVX and EVEX we will use the legacy FXSAVE area for xmm0..xmm15,
 248   // on EVEX enabled targets, we get it included in the xsave area
 249   off = xmm0_off;
 250   int delta = xmm1_off - off;
 251   for (int n = 0; n < 16; n++) {
 252     XMMRegister xmm_name = as_XMMRegister(n);
 253     map->set_callee_saved(STACK_OFFSET(off), xmm_name->as_VMReg());
 254     off += delta;
 255   }
 256   if(UseAVX > 2) {
 257     // Obtain xmm16..xmm31 from the XSAVE area on EVEX enabled targets
 258     off = zmm16_off;
 259     delta = zmm17_off - off;
 260     for (int n = 16; n < num_xmm_regs; n++) {
 261       XMMRegister zmm_name = as_XMMRegister(n);
 262       map->set_callee_saved(STACK_OFFSET(off), zmm_name->as_VMReg());
 263       off += delta;
 264     }
 265   }
 266 
 267 #if COMPILER2_OR_JVMCI
 268   if (save_vectors) {
 269     off = ymm0_off;
 270     int delta = ymm1_off - off;
 271     for (int n = 0; n < 16; n++) {
 272       XMMRegister ymm_name = as_XMMRegister(n);
 273       map->set_callee_saved(STACK_OFFSET(off), ymm_name->as_VMReg()->next(4));
 274       off += delta;
 275     }
 276   }
 277 #endif // COMPILER2_OR_JVMCI
 278 
 279   // %%% These should all be a waste but we'll keep things as they were for now
 280   if (true) {
 281     map->set_callee_saved(STACK_OFFSET( raxH_off ), rax->as_VMReg()->next());
 282     map->set_callee_saved(STACK_OFFSET( rcxH_off ), rcx->as_VMReg()->next());
 283     map->set_callee_saved(STACK_OFFSET( rdxH_off ), rdx->as_VMReg()->next());
 284     map->set_callee_saved(STACK_OFFSET( rbxH_off ), rbx->as_VMReg()->next());
 285     // rbp location is known implicitly by the frame sender code, needs no oopmap
 286     map->set_callee_saved(STACK_OFFSET( rsiH_off ), rsi->as_VMReg()->next());
 287     map->set_callee_saved(STACK_OFFSET( rdiH_off ), rdi->as_VMReg()->next());
 288     map->set_callee_saved(STACK_OFFSET( r8H_off  ), r8->as_VMReg()->next());
 289     map->set_callee_saved(STACK_OFFSET( r9H_off  ), r9->as_VMReg()->next());
 290     map->set_callee_saved(STACK_OFFSET( r10H_off ), r10->as_VMReg()->next());
 291     map->set_callee_saved(STACK_OFFSET( r11H_off ), r11->as_VMReg()->next());
 292     map->set_callee_saved(STACK_OFFSET( r12H_off ), r12->as_VMReg()->next());
 293     map->set_callee_saved(STACK_OFFSET( r13H_off ), r13->as_VMReg()->next());
 294     map->set_callee_saved(STACK_OFFSET( r14H_off ), r14->as_VMReg()->next());
 295     map->set_callee_saved(STACK_OFFSET( r15H_off ), r15->as_VMReg()->next());
 296     // For both AVX and EVEX we will use the legacy FXSAVE area for xmm0..xmm15,
 297     // on EVEX enabled targets, we get it included in the xsave area
 298     off = xmm0H_off;
 299     delta = xmm1H_off - off;
 300     for (int n = 0; n < 16; n++) {
 301       XMMRegister xmm_name = as_XMMRegister(n);
 302       map->set_callee_saved(STACK_OFFSET(off), xmm_name->as_VMReg()->next());
 303       off += delta;
 304     }
 305     if (UseAVX > 2) {
 306       // Obtain xmm16..xmm31 from the XSAVE area on EVEX enabled targets
 307       off = zmm16H_off;
 308       delta = zmm17H_off - off;
 309       for (int n = 16; n < num_xmm_regs; n++) {
 310         XMMRegister zmm_name = as_XMMRegister(n);
 311         map->set_callee_saved(STACK_OFFSET(off), zmm_name->as_VMReg()->next());
 312         off += delta;
 313       }
 314     }
 315   }
 316 
 317   return map;
 318 }
 319 
 320 void RegisterSaver::restore_live_registers(MacroAssembler* masm, bool restore_vectors) {
 321   int num_xmm_regs = XMMRegisterImpl::number_of_registers;
 322   if (UseAVX < 3) {
 323     num_xmm_regs = num_xmm_regs/2;
 324   }
 325   if (frame::arg_reg_save_area_bytes != 0) {
 326     // Pop arg register save area
 327     __ addptr(rsp, frame::arg_reg_save_area_bytes);
 328   }
 329 
 330 #if COMPILER2_OR_JVMCI
 331   if (restore_vectors) {
 332     assert(UseAVX > 0, "Vectors larger than 16 byte long are supported only with AVX");
 333     assert(MaxVectorSize <= 64, "Only up to 64 byte long vectors are supported");
 334   }
 335 #else
 336   assert(!restore_vectors, "vectors are generated only by C2");
 337 #endif
 338 
 339   __ vzeroupper();
 340 
 341   // On EVEX enabled targets everything is handled in pop fpu state
 342   if (restore_vectors) {
 343     // Restore upper half of YMM registers (0..15)
 344     int base_addr = XSAVE_AREA_YMM_BEGIN;
 345     for (int n = 0; n < 16; n++) {
 346       __ vinsertf128_high(as_XMMRegister(n), Address(rsp, base_addr+n*16));
 347     }
 348     if (VM_Version::supports_evex()) {
 349       // Restore upper half of ZMM registers (0..15)
 350       base_addr = XSAVE_AREA_ZMM_BEGIN;
 351       for (int n = 0; n < 16; n++) {
 352         __ vinsertf64x4_high(as_XMMRegister(n), Address(rsp, base_addr+n*32));
 353       }
 354       // Restore full ZMM registers(16..num_xmm_regs)
 355       base_addr = XSAVE_AREA_UPPERBANK;
 356       int vector_len = Assembler::AVX_512bit;
 357       int off = 0;
 358       for (int n = 16; n < num_xmm_regs; n++) {
 359         __ evmovdqul(as_XMMRegister(n), Address(rsp, base_addr+(off++*64)), vector_len);
 360       }
 361     }
 362   } else {
 363     if (VM_Version::supports_evex()) {
 364       // Restore upper bank of ZMM registers(16..31) for double/float usage
 365       int base_addr = XSAVE_AREA_UPPERBANK;
 366       int off = 0;
 367       for (int n = 16; n < num_xmm_regs; n++) {
 368         __ movsd(as_XMMRegister(n), Address(rsp, base_addr+(off++*64)));
 369       }
 370     }
 371   }
 372 
 373   // Recover CPU state
 374   __ pop_CPU_state();
 375   // Get the rbp described implicitly by the calling convention (no oopMap)
 376   __ pop(rbp);
 377 }
 378 
 379 void RegisterSaver::restore_result_registers(MacroAssembler* masm) {
 380 
 381   // Just restore result register. Only used by deoptimization. By
 382   // now any callee save register that needs to be restored to a c2
 383   // caller of the deoptee has been extracted into the vframeArray
 384   // and will be stuffed into the c2i adapter we create for later
 385   // restoration so only result registers need to be restored here.
 386 
 387   // Restore fp result register
 388   __ movdbl(xmm0, Address(rsp, xmm0_offset_in_bytes()));
 389   // Restore integer result register
 390   __ movptr(rax, Address(rsp, rax_offset_in_bytes()));
 391   __ movptr(rdx, Address(rsp, rdx_offset_in_bytes()));
 392 
 393   // Pop all of the register save are off the stack except the return address
 394   __ addptr(rsp, return_offset_in_bytes());
 395 }
 396 
 397 // Is vector's size (in bytes) bigger than a size saved by default?
 398 // 16 bytes XMM registers are saved by default using fxsave/fxrstor instructions.
 399 bool SharedRuntime::is_wide_vector(int size) {
 400   return size > 16;
 401 }
 402 
 403 size_t SharedRuntime::trampoline_size() {
 404   return 16;
 405 }
 406 
 407 void SharedRuntime::generate_trampoline(MacroAssembler *masm, address destination) {
 408   __ jump(RuntimeAddress(destination));
 409 }
 410 
 411 // The java_calling_convention describes stack locations as ideal slots on
 412 // a frame with no abi restrictions. Since we must observe abi restrictions
 413 // (like the placement of the register window) the slots must be biased by
 414 // the following value.
 415 static int reg2offset_in(VMReg r) {
 416   // Account for saved rbp and return address
 417   // This should really be in_preserve_stack_slots
 418   return (r->reg2stack() + 4) * VMRegImpl::stack_slot_size;
 419 }
 420 
 421 static int reg2offset_out(VMReg r) {
 422   return (r->reg2stack() + SharedRuntime::out_preserve_stack_slots()) * VMRegImpl::stack_slot_size;
 423 }
 424 
 425 // ---------------------------------------------------------------------------
 426 // Read the array of BasicTypes from a signature, and compute where the
 427 // arguments should go.  Values in the VMRegPair regs array refer to 4-byte
 428 // quantities.  Values less than VMRegImpl::stack0 are registers, those above
 429 // refer to 4-byte stack slots.  All stack slots are based off of the stack pointer
 430 // as framesizes are fixed.
 431 // VMRegImpl::stack0 refers to the first slot 0(sp).
 432 // and VMRegImpl::stack0+1 refers to the memory word 4-byes higher.  Register
 433 // up to RegisterImpl::number_of_registers) are the 64-bit
 434 // integer registers.
 435 
 436 // Note: the INPUTS in sig_bt are in units of Java argument words, which are
 437 // either 32-bit or 64-bit depending on the build.  The OUTPUTS are in 32-bit
 438 // units regardless of build. Of course for i486 there is no 64 bit build
 439 
 440 // The Java calling convention is a "shifted" version of the C ABI.
 441 // By skipping the first C ABI register we can call non-static jni methods
 442 // with small numbers of arguments without having to shuffle the arguments
 443 // at all. Since we control the java ABI we ought to at least get some
 444 // advantage out of it.
 445 
 446 int SharedRuntime::java_calling_convention(const BasicType *sig_bt,
 447                                            VMRegPair *regs,
 448                                            int total_args_passed,
 449                                            int is_outgoing) {
 450 
 451   // Create the mapping between argument positions and
 452   // registers.
 453   static const Register INT_ArgReg[Argument::n_int_register_parameters_j] = {
 454     j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5
 455   };
 456   static const XMMRegister FP_ArgReg[Argument::n_float_register_parameters_j] = {
 457     j_farg0, j_farg1, j_farg2, j_farg3,
 458     j_farg4, j_farg5, j_farg6, j_farg7
 459   };
 460 
 461 
 462   uint int_args = 0;
 463   uint fp_args = 0;
 464   uint stk_args = 0; // inc by 2 each time
 465 
 466   for (int i = 0; i < total_args_passed; i++) {
 467     switch (sig_bt[i]) {
 468     case T_BOOLEAN:
 469     case T_CHAR:
 470     case T_BYTE:
 471     case T_SHORT:
 472     case T_INT:
 473       if (int_args < Argument::n_int_register_parameters_j) {
 474         regs[i].set1(INT_ArgReg[int_args++]->as_VMReg());
 475       } else {
 476         regs[i].set1(VMRegImpl::stack2reg(stk_args));
 477         stk_args += 2;
 478       }
 479       break;
 480     case T_VOID:
 481       // halves of T_LONG or T_DOUBLE
 482       assert(i != 0 && (sig_bt[i - 1] == T_LONG || sig_bt[i - 1] == T_DOUBLE), "expecting half");
 483       regs[i].set_bad();
 484       break;
 485     case T_LONG:
 486       assert((i + 1) < total_args_passed && sig_bt[i + 1] == T_VOID, "expecting half");
 487       // fall through
 488     case T_OBJECT:
 489     case T_ARRAY:
 490     case T_ADDRESS:
 491       if (int_args < Argument::n_int_register_parameters_j) {
 492         regs[i].set2(INT_ArgReg[int_args++]->as_VMReg());
 493       } else {
 494         regs[i].set2(VMRegImpl::stack2reg(stk_args));
 495         stk_args += 2;
 496       }
 497       break;
 498     case T_FLOAT:
 499       if (fp_args < Argument::n_float_register_parameters_j) {
 500         regs[i].set1(FP_ArgReg[fp_args++]->as_VMReg());
 501       } else {
 502         regs[i].set1(VMRegImpl::stack2reg(stk_args));
 503         stk_args += 2;
 504       }
 505       break;
 506     case T_DOUBLE:
 507       assert((i + 1) < total_args_passed && sig_bt[i + 1] == T_VOID, "expecting half");
 508       if (fp_args < Argument::n_float_register_parameters_j) {
 509         regs[i].set2(FP_ArgReg[fp_args++]->as_VMReg());
 510       } else {
 511         regs[i].set2(VMRegImpl::stack2reg(stk_args));
 512         stk_args += 2;
 513       }
 514       break;
 515     default:
 516       ShouldNotReachHere();
 517       break;
 518     }
 519   }
 520 
 521   return align_up(stk_args, 2);
 522 }
 523 
 524 // Patch the callers callsite with entry to compiled code if it exists.
 525 static void patch_callers_callsite(MacroAssembler *masm) {
 526   Label L;
 527   __ cmpptr(Address(rbx, in_bytes(Method::code_offset())), (int32_t)NULL_WORD);
 528   __ jcc(Assembler::equal, L);
 529 
 530   // Save the current stack pointer
 531   __ mov(r13, rsp);
 532   // Schedule the branch target address early.
 533   // Call into the VM to patch the caller, then jump to compiled callee
 534   // rax isn't live so capture return address while we easily can
 535   __ movptr(rax, Address(rsp, 0));
 536 
 537   // align stack so push_CPU_state doesn't fault
 538   __ andptr(rsp, -(StackAlignmentInBytes));
 539   __ push_CPU_state();
 540   __ vzeroupper();
 541   // VM needs caller's callsite
 542   // VM needs target method
 543   // This needs to be a long call since we will relocate this adapter to
 544   // the codeBuffer and it may not reach
 545 
 546   // Allocate argument register save area
 547   if (frame::arg_reg_save_area_bytes != 0) {
 548     __ subptr(rsp, frame::arg_reg_save_area_bytes);
 549   }
 550   __ mov(c_rarg0, rbx);
 551   __ mov(c_rarg1, rax);
 552   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::fixup_callers_callsite)));
 553 
 554   // De-allocate argument register save area
 555   if (frame::arg_reg_save_area_bytes != 0) {
 556     __ addptr(rsp, frame::arg_reg_save_area_bytes);
 557   }
 558 
 559   __ vzeroupper();
 560   __ pop_CPU_state();
 561   // restore sp
 562   __ mov(rsp, r13);
 563   __ bind(L);
 564 }
 565 
 566 
 567 static void gen_c2i_adapter(MacroAssembler *masm,
 568                             int total_args_passed,
 569                             int comp_args_on_stack,
 570                             const BasicType *sig_bt,
 571                             const VMRegPair *regs,
 572                             Label& skip_fixup) {
 573   // Before we get into the guts of the C2I adapter, see if we should be here
 574   // at all.  We've come from compiled code and are attempting to jump to the
 575   // interpreter, which means the caller made a static call to get here
 576   // (vcalls always get a compiled target if there is one).  Check for a
 577   // compiled target.  If there is one, we need to patch the caller's call.
 578   patch_callers_callsite(masm);
 579 
 580   __ bind(skip_fixup);
 581 
 582   // Since all args are passed on the stack, total_args_passed *
 583   // Interpreter::stackElementSize is the space we need. Plus 1 because
 584   // we also account for the return address location since
 585   // we store it first rather than hold it in rax across all the shuffling
 586 
 587   int extraspace = (total_args_passed * Interpreter::stackElementSize) + wordSize;
 588 
 589   // stack is aligned, keep it that way
 590   extraspace = align_up(extraspace, 2*wordSize);
 591 
 592   // Get return address
 593   __ pop(rax);
 594 
 595   // set senderSP value
 596   __ mov(r13, rsp);
 597 
 598   __ subptr(rsp, extraspace);
 599 
 600   // Store the return address in the expected location
 601   __ movptr(Address(rsp, 0), rax);
 602 
 603   // Now write the args into the outgoing interpreter space
 604   for (int i = 0; i < total_args_passed; i++) {
 605     if (sig_bt[i] == T_VOID) {
 606       assert(i > 0 && (sig_bt[i-1] == T_LONG || sig_bt[i-1] == T_DOUBLE), "missing half");
 607       continue;
 608     }
 609 
 610     // offset to start parameters
 611     int st_off   = (total_args_passed - i) * Interpreter::stackElementSize;
 612     int next_off = st_off - Interpreter::stackElementSize;
 613 
 614     // Say 4 args:
 615     // i   st_off
 616     // 0   32 T_LONG
 617     // 1   24 T_VOID
 618     // 2   16 T_OBJECT
 619     // 3    8 T_BOOL
 620     // -    0 return address
 621     //
 622     // However to make thing extra confusing. Because we can fit a long/double in
 623     // a single slot on a 64 bt vm and it would be silly to break them up, the interpreter
 624     // leaves one slot empty and only stores to a single slot. In this case the
 625     // slot that is occupied is the T_VOID slot. See I said it was confusing.
 626 
 627     VMReg r_1 = regs[i].first();
 628     VMReg r_2 = regs[i].second();
 629     if (!r_1->is_valid()) {
 630       assert(!r_2->is_valid(), "");
 631       continue;
 632     }
 633     if (r_1->is_stack()) {
 634       // memory to memory use rax
 635       int ld_off = r_1->reg2stack() * VMRegImpl::stack_slot_size + extraspace;
 636       if (!r_2->is_valid()) {
 637         // sign extend??
 638         __ movl(rax, Address(rsp, ld_off));
 639         __ movptr(Address(rsp, st_off), rax);
 640 
 641       } else {
 642 
 643         __ movq(rax, Address(rsp, ld_off));
 644 
 645         // Two VMREgs|OptoRegs can be T_OBJECT, T_ADDRESS, T_DOUBLE, T_LONG
 646         // T_DOUBLE and T_LONG use two slots in the interpreter
 647         if ( sig_bt[i] == T_LONG || sig_bt[i] == T_DOUBLE) {
 648           // ld_off == LSW, ld_off+wordSize == MSW
 649           // st_off == MSW, next_off == LSW
 650           __ movq(Address(rsp, next_off), rax);
 651 #ifdef ASSERT
 652           // Overwrite the unused slot with known junk
 653           __ mov64(rax, CONST64(0xdeadffffdeadaaaa));
 654           __ movptr(Address(rsp, st_off), rax);
 655 #endif /* ASSERT */
 656         } else {
 657           __ movq(Address(rsp, st_off), rax);
 658         }
 659       }
 660     } else if (r_1->is_Register()) {
 661       Register r = r_1->as_Register();
 662       if (!r_2->is_valid()) {
 663         // must be only an int (or less ) so move only 32bits to slot
 664         // why not sign extend??
 665         __ movl(Address(rsp, st_off), r);
 666       } else {
 667         // Two VMREgs|OptoRegs can be T_OBJECT, T_ADDRESS, T_DOUBLE, T_LONG
 668         // T_DOUBLE and T_LONG use two slots in the interpreter
 669         if ( sig_bt[i] == T_LONG || sig_bt[i] == T_DOUBLE) {
 670           // long/double in gpr
 671 #ifdef ASSERT
 672           // Overwrite the unused slot with known junk
 673           __ mov64(rax, CONST64(0xdeadffffdeadaaab));
 674           __ movptr(Address(rsp, st_off), rax);
 675 #endif /* ASSERT */
 676           __ movq(Address(rsp, next_off), r);
 677         } else {
 678           __ movptr(Address(rsp, st_off), r);
 679         }
 680       }
 681     } else {
 682       assert(r_1->is_XMMRegister(), "");
 683       if (!r_2->is_valid()) {
 684         // only a float use just part of the slot
 685         __ movflt(Address(rsp, st_off), r_1->as_XMMRegister());
 686       } else {
 687 #ifdef ASSERT
 688         // Overwrite the unused slot with known junk
 689         __ mov64(rax, CONST64(0xdeadffffdeadaaac));
 690         __ movptr(Address(rsp, st_off), rax);
 691 #endif /* ASSERT */
 692         __ movdbl(Address(rsp, next_off), r_1->as_XMMRegister());
 693       }
 694     }
 695   }
 696 
 697   // Schedule the branch target address early.
 698   __ movptr(rcx, Address(rbx, in_bytes(Method::interpreter_entry_offset())));
 699   __ jmp(rcx);
 700 }
 701 
 702 static void range_check(MacroAssembler* masm, Register pc_reg, Register temp_reg,
 703                         address code_start, address code_end,
 704                         Label& L_ok) {
 705   Label L_fail;
 706   __ lea(temp_reg, ExternalAddress(code_start));
 707   __ cmpptr(pc_reg, temp_reg);
 708   __ jcc(Assembler::belowEqual, L_fail);
 709   __ lea(temp_reg, ExternalAddress(code_end));
 710   __ cmpptr(pc_reg, temp_reg);
 711   __ jcc(Assembler::below, L_ok);
 712   __ bind(L_fail);
 713 }
 714 
 715 void SharedRuntime::gen_i2c_adapter(MacroAssembler *masm,
 716                                     int total_args_passed,
 717                                     int comp_args_on_stack,
 718                                     const BasicType *sig_bt,
 719                                     const VMRegPair *regs) {
 720 
 721   // Note: r13 contains the senderSP on entry. We must preserve it since
 722   // we may do a i2c -> c2i transition if we lose a race where compiled
 723   // code goes non-entrant while we get args ready.
 724   // In addition we use r13 to locate all the interpreter args as
 725   // we must align the stack to 16 bytes on an i2c entry else we
 726   // lose alignment we expect in all compiled code and register
 727   // save code can segv when fxsave instructions find improperly
 728   // aligned stack pointer.
 729 
 730   // Adapters can be frameless because they do not require the caller
 731   // to perform additional cleanup work, such as correcting the stack pointer.
 732   // An i2c adapter is frameless because the *caller* frame, which is interpreted,
 733   // routinely repairs its own stack pointer (from interpreter_frame_last_sp),
 734   // even if a callee has modified the stack pointer.
 735   // A c2i adapter is frameless because the *callee* frame, which is interpreted,
 736   // routinely repairs its caller's stack pointer (from sender_sp, which is set
 737   // up via the senderSP register).
 738   // In other words, if *either* the caller or callee is interpreted, we can
 739   // get the stack pointer repaired after a call.
 740   // This is why c2i and i2c adapters cannot be indefinitely composed.
 741   // In particular, if a c2i adapter were to somehow call an i2c adapter,
 742   // both caller and callee would be compiled methods, and neither would
 743   // clean up the stack pointer changes performed by the two adapters.
 744   // If this happens, control eventually transfers back to the compiled
 745   // caller, but with an uncorrected stack, causing delayed havoc.
 746 
 747   // Pick up the return address
 748   __ movptr(rax, Address(rsp, 0));
 749 
 750   if (VerifyAdapterCalls &&
 751       (Interpreter::code() != NULL || StubRoutines::code1() != NULL)) {
 752     // So, let's test for cascading c2i/i2c adapters right now.
 753     //  assert(Interpreter::contains($return_addr) ||
 754     //         StubRoutines::contains($return_addr),
 755     //         "i2c adapter must return to an interpreter frame");
 756     __ block_comment("verify_i2c { ");
 757     Label L_ok;
 758     if (Interpreter::code() != NULL)
 759       range_check(masm, rax, r11,
 760                   Interpreter::code()->code_start(), Interpreter::code()->code_end(),
 761                   L_ok);
 762     if (StubRoutines::code1() != NULL)
 763       range_check(masm, rax, r11,
 764                   StubRoutines::code1()->code_begin(), StubRoutines::code1()->code_end(),
 765                   L_ok);
 766     if (StubRoutines::code2() != NULL)
 767       range_check(masm, rax, r11,
 768                   StubRoutines::code2()->code_begin(), StubRoutines::code2()->code_end(),
 769                   L_ok);
 770     const char* msg = "i2c adapter must return to an interpreter frame";
 771     __ block_comment(msg);
 772     __ stop(msg);
 773     __ bind(L_ok);
 774     __ block_comment("} verify_i2ce ");
 775   }
 776 
 777   // Must preserve original SP for loading incoming arguments because
 778   // we need to align the outgoing SP for compiled code.
 779   __ movptr(r11, rsp);
 780 
 781   // Cut-out for having no stack args.  Since up to 2 int/oop args are passed
 782   // in registers, we will occasionally have no stack args.
 783   int comp_words_on_stack = 0;
 784   if (comp_args_on_stack) {
 785     // Sig words on the stack are greater-than VMRegImpl::stack0.  Those in
 786     // registers are below.  By subtracting stack0, we either get a negative
 787     // number (all values in registers) or the maximum stack slot accessed.
 788 
 789     // Convert 4-byte c2 stack slots to words.
 790     comp_words_on_stack = align_up(comp_args_on_stack*VMRegImpl::stack_slot_size, wordSize)>>LogBytesPerWord;
 791     // Round up to miminum stack alignment, in wordSize
 792     comp_words_on_stack = align_up(comp_words_on_stack, 2);
 793     __ subptr(rsp, comp_words_on_stack * wordSize);
 794   }
 795 
 796 
 797   // Ensure compiled code always sees stack at proper alignment
 798   __ andptr(rsp, -16);
 799 
 800   // push the return address and misalign the stack that youngest frame always sees
 801   // as far as the placement of the call instruction
 802   __ push(rax);
 803 
 804   // Put saved SP in another register
 805   const Register saved_sp = rax;
 806   __ movptr(saved_sp, r11);
 807 
 808   // Will jump to the compiled code just as if compiled code was doing it.
 809   // Pre-load the register-jump target early, to schedule it better.
 810   __ movptr(r11, Address(rbx, in_bytes(Method::from_compiled_offset())));
 811 
 812 #if INCLUDE_JVMCI
 813   if (EnableJVMCI || UseAOT) {
 814     // check if this call should be routed towards a specific entry point
 815     __ cmpptr(Address(r15_thread, in_bytes(JavaThread::jvmci_alternate_call_target_offset())), 0);
 816     Label no_alternative_target;
 817     __ jcc(Assembler::equal, no_alternative_target);
 818     __ movptr(r11, Address(r15_thread, in_bytes(JavaThread::jvmci_alternate_call_target_offset())));
 819     __ movptr(Address(r15_thread, in_bytes(JavaThread::jvmci_alternate_call_target_offset())), 0);
 820     __ bind(no_alternative_target);
 821   }
 822 #endif // INCLUDE_JVMCI
 823 
 824   // Now generate the shuffle code.  Pick up all register args and move the
 825   // rest through the floating point stack top.
 826   for (int i = 0; i < total_args_passed; i++) {
 827     if (sig_bt[i] == T_VOID) {
 828       // Longs and doubles are passed in native word order, but misaligned
 829       // in the 32-bit build.
 830       assert(i > 0 && (sig_bt[i-1] == T_LONG || sig_bt[i-1] == T_DOUBLE), "missing half");
 831       continue;
 832     }
 833 
 834     // Pick up 0, 1 or 2 words from SP+offset.
 835 
 836     assert(!regs[i].second()->is_valid() || regs[i].first()->next() == regs[i].second(),
 837             "scrambled load targets?");
 838     // Load in argument order going down.
 839     int ld_off = (total_args_passed - i)*Interpreter::stackElementSize;
 840     // Point to interpreter value (vs. tag)
 841     int next_off = ld_off - Interpreter::stackElementSize;
 842     //
 843     //
 844     //
 845     VMReg r_1 = regs[i].first();
 846     VMReg r_2 = regs[i].second();
 847     if (!r_1->is_valid()) {
 848       assert(!r_2->is_valid(), "");
 849       continue;
 850     }
 851     if (r_1->is_stack()) {
 852       // Convert stack slot to an SP offset (+ wordSize to account for return address )
 853       int st_off = regs[i].first()->reg2stack()*VMRegImpl::stack_slot_size + wordSize;
 854 
 855       // We can use r13 as a temp here because compiled code doesn't need r13 as an input
 856       // and if we end up going thru a c2i because of a miss a reasonable value of r13
 857       // will be generated.
 858       if (!r_2->is_valid()) {
 859         // sign extend???
 860         __ movl(r13, Address(saved_sp, ld_off));
 861         __ movptr(Address(rsp, st_off), r13);
 862       } else {
 863         //
 864         // We are using two optoregs. This can be either T_OBJECT, T_ADDRESS, T_LONG, or T_DOUBLE
 865         // the interpreter allocates two slots but only uses one for thr T_LONG or T_DOUBLE case
 866         // So we must adjust where to pick up the data to match the interpreter.
 867         //
 868         // Interpreter local[n] == MSW, local[n+1] == LSW however locals
 869         // are accessed as negative so LSW is at LOW address
 870 
 871         // ld_off is MSW so get LSW
 872         const int offset = (sig_bt[i]==T_LONG||sig_bt[i]==T_DOUBLE)?
 873                            next_off : ld_off;
 874         __ movq(r13, Address(saved_sp, offset));
 875         // st_off is LSW (i.e. reg.first())
 876         __ movq(Address(rsp, st_off), r13);
 877       }
 878     } else if (r_1->is_Register()) {  // Register argument
 879       Register r = r_1->as_Register();
 880       assert(r != rax, "must be different");
 881       if (r_2->is_valid()) {
 882         //
 883         // We are using two VMRegs. This can be either T_OBJECT, T_ADDRESS, T_LONG, or T_DOUBLE
 884         // the interpreter allocates two slots but only uses one for thr T_LONG or T_DOUBLE case
 885         // So we must adjust where to pick up the data to match the interpreter.
 886 
 887         const int offset = (sig_bt[i]==T_LONG||sig_bt[i]==T_DOUBLE)?
 888                            next_off : ld_off;
 889 
 890         // this can be a misaligned move
 891         __ movq(r, Address(saved_sp, offset));
 892       } else {
 893         // sign extend and use a full word?
 894         __ movl(r, Address(saved_sp, ld_off));
 895       }
 896     } else {
 897       if (!r_2->is_valid()) {
 898         __ movflt(r_1->as_XMMRegister(), Address(saved_sp, ld_off));
 899       } else {
 900         __ movdbl(r_1->as_XMMRegister(), Address(saved_sp, next_off));
 901       }
 902     }
 903   }
 904 
 905   // 6243940 We might end up in handle_wrong_method if
 906   // the callee is deoptimized as we race thru here. If that
 907   // happens we don't want to take a safepoint because the
 908   // caller frame will look interpreted and arguments are now
 909   // "compiled" so it is much better to make this transition
 910   // invisible to the stack walking code. Unfortunately if
 911   // we try and find the callee by normal means a safepoint
 912   // is possible. So we stash the desired callee in the thread
 913   // and the vm will find there should this case occur.
 914 
 915   __ movptr(Address(r15_thread, JavaThread::callee_target_offset()), rbx);
 916 
 917   // put Method* where a c2i would expect should we end up there
 918   // only needed becaus eof c2 resolve stubs return Method* as a result in
 919   // rax
 920   __ mov(rax, rbx);
 921   __ jmp(r11);
 922 }
 923 
 924 // ---------------------------------------------------------------
 925 AdapterHandlerEntry* SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm,
 926                                                             int total_args_passed,
 927                                                             int comp_args_on_stack,
 928                                                             const BasicType *sig_bt,
 929                                                             const VMRegPair *regs,
 930                                                             AdapterFingerPrint* fingerprint) {
 931   address i2c_entry = __ pc();
 932 
 933   gen_i2c_adapter(masm, total_args_passed, comp_args_on_stack, sig_bt, regs);
 934 
 935   // -------------------------------------------------------------------------
 936   // Generate a C2I adapter.  On entry we know rbx holds the Method* during calls
 937   // to the interpreter.  The args start out packed in the compiled layout.  They
 938   // need to be unpacked into the interpreter layout.  This will almost always
 939   // require some stack space.  We grow the current (compiled) stack, then repack
 940   // the args.  We  finally end in a jump to the generic interpreter entry point.
 941   // On exit from the interpreter, the interpreter will restore our SP (lest the
 942   // compiled code, which relys solely on SP and not RBP, get sick).
 943 
 944   address c2i_unverified_entry = __ pc();
 945   Label skip_fixup;
 946   Label ok;
 947 
 948   Register holder = rax;
 949   Register receiver = j_rarg0;
 950   Register temp = rbx;
 951 
 952   {
 953     __ load_klass(temp, receiver);
 954     __ cmpptr(temp, Address(holder, CompiledICHolder::holder_klass_offset()));
 955     __ movptr(rbx, Address(holder, CompiledICHolder::holder_metadata_offset()));
 956     __ jcc(Assembler::equal, ok);
 957     __ jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
 958 
 959     __ bind(ok);
 960     // Method might have been compiled since the call site was patched to
 961     // interpreted if that is the case treat it as a miss so we can get
 962     // the call site corrected.
 963     __ cmpptr(Address(rbx, in_bytes(Method::code_offset())), (int32_t)NULL_WORD);
 964     __ jcc(Assembler::equal, skip_fixup);
 965     __ jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
 966   }
 967 
 968   address c2i_entry = __ pc();
 969 
 970   gen_c2i_adapter(masm, total_args_passed, comp_args_on_stack, sig_bt, regs, skip_fixup);
 971 
 972   __ flush();
 973   return AdapterHandlerLibrary::new_entry(fingerprint, i2c_entry, c2i_entry, c2i_unverified_entry);
 974 }
 975 
 976 int SharedRuntime::c_calling_convention(const BasicType *sig_bt,
 977                                          VMRegPair *regs,
 978                                          VMRegPair *regs2,
 979                                          int total_args_passed) {
 980   assert(regs2 == NULL, "not needed on x86");
 981 // We return the amount of VMRegImpl stack slots we need to reserve for all
 982 // the arguments NOT counting out_preserve_stack_slots.
 983 
 984 // NOTE: These arrays will have to change when c1 is ported
 985 #ifdef _WIN64
 986     static const Register INT_ArgReg[Argument::n_int_register_parameters_c] = {
 987       c_rarg0, c_rarg1, c_rarg2, c_rarg3
 988     };
 989     static const XMMRegister FP_ArgReg[Argument::n_float_register_parameters_c] = {
 990       c_farg0, c_farg1, c_farg2, c_farg3
 991     };
 992 #else
 993     static const Register INT_ArgReg[Argument::n_int_register_parameters_c] = {
 994       c_rarg0, c_rarg1, c_rarg2, c_rarg3, c_rarg4, c_rarg5
 995     };
 996     static const XMMRegister FP_ArgReg[Argument::n_float_register_parameters_c] = {
 997       c_farg0, c_farg1, c_farg2, c_farg3,
 998       c_farg4, c_farg5, c_farg6, c_farg7
 999     };
1000 #endif // _WIN64
1001 
1002 
1003     uint int_args = 0;
1004     uint fp_args = 0;
1005     uint stk_args = 0; // inc by 2 each time
1006 
1007     for (int i = 0; i < total_args_passed; i++) {
1008       switch (sig_bt[i]) {
1009       case T_BOOLEAN:
1010       case T_CHAR:
1011       case T_BYTE:
1012       case T_SHORT:
1013       case T_INT:
1014         if (int_args < Argument::n_int_register_parameters_c) {
1015           regs[i].set1(INT_ArgReg[int_args++]->as_VMReg());
1016 #ifdef _WIN64
1017           fp_args++;
1018           // Allocate slots for callee to stuff register args the stack.
1019           stk_args += 2;
1020 #endif
1021         } else {
1022           regs[i].set1(VMRegImpl::stack2reg(stk_args));
1023           stk_args += 2;
1024         }
1025         break;
1026       case T_LONG:
1027         assert((i + 1) < total_args_passed && sig_bt[i + 1] == T_VOID, "expecting half");
1028         // fall through
1029       case T_OBJECT:
1030       case T_ARRAY:
1031       case T_ADDRESS:
1032       case T_METADATA:
1033         if (int_args < Argument::n_int_register_parameters_c) {
1034           regs[i].set2(INT_ArgReg[int_args++]->as_VMReg());
1035 #ifdef _WIN64
1036           fp_args++;
1037           stk_args += 2;
1038 #endif
1039         } else {
1040           regs[i].set2(VMRegImpl::stack2reg(stk_args));
1041           stk_args += 2;
1042         }
1043         break;
1044       case T_FLOAT:
1045         if (fp_args < Argument::n_float_register_parameters_c) {
1046           regs[i].set1(FP_ArgReg[fp_args++]->as_VMReg());
1047 #ifdef _WIN64
1048           int_args++;
1049           // Allocate slots for callee to stuff register args the stack.
1050           stk_args += 2;
1051 #endif
1052         } else {
1053           regs[i].set1(VMRegImpl::stack2reg(stk_args));
1054           stk_args += 2;
1055         }
1056         break;
1057       case T_DOUBLE:
1058         assert((i + 1) < total_args_passed && sig_bt[i + 1] == T_VOID, "expecting half");
1059         if (fp_args < Argument::n_float_register_parameters_c) {
1060           regs[i].set2(FP_ArgReg[fp_args++]->as_VMReg());
1061 #ifdef _WIN64
1062           int_args++;
1063           // Allocate slots for callee to stuff register args the stack.
1064           stk_args += 2;
1065 #endif
1066         } else {
1067           regs[i].set2(VMRegImpl::stack2reg(stk_args));
1068           stk_args += 2;
1069         }
1070         break;
1071       case T_VOID: // Halves of longs and doubles
1072         assert(i != 0 && (sig_bt[i - 1] == T_LONG || sig_bt[i - 1] == T_DOUBLE), "expecting half");
1073         regs[i].set_bad();
1074         break;
1075       default:
1076         ShouldNotReachHere();
1077         break;
1078       }
1079     }
1080 #ifdef _WIN64
1081   // windows abi requires that we always allocate enough stack space
1082   // for 4 64bit registers to be stored down.
1083   if (stk_args < 8) {
1084     stk_args = 8;
1085   }
1086 #endif // _WIN64
1087 
1088   return stk_args;
1089 }
1090 
1091 // On 64 bit we will store integer like items to the stack as
1092 // 64 bits items (sparc abi) even though java would only store
1093 // 32bits for a parameter. On 32bit it will simply be 32 bits
1094 // So this routine will do 32->32 on 32bit and 32->64 on 64bit
1095 static void move32_64(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
1096   if (src.first()->is_stack()) {
1097     if (dst.first()->is_stack()) {
1098       // stack to stack
1099       __ movslq(rax, Address(rbp, reg2offset_in(src.first())));
1100       __ movq(Address(rsp, reg2offset_out(dst.first())), rax);
1101     } else {
1102       // stack to reg
1103       __ movslq(dst.first()->as_Register(), Address(rbp, reg2offset_in(src.first())));
1104     }
1105   } else if (dst.first()->is_stack()) {
1106     // reg to stack
1107     // Do we really have to sign extend???
1108     // __ movslq(src.first()->as_Register(), src.first()->as_Register());
1109     __ movq(Address(rsp, reg2offset_out(dst.first())), src.first()->as_Register());
1110   } else {
1111     // Do we really have to sign extend???
1112     // __ movslq(dst.first()->as_Register(), src.first()->as_Register());
1113     if (dst.first() != src.first()) {
1114       __ movq(dst.first()->as_Register(), src.first()->as_Register());
1115     }
1116   }
1117 }
1118 
1119 static void move_ptr(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
1120   if (src.first()->is_stack()) {
1121     if (dst.first()->is_stack()) {
1122       // stack to stack
1123       __ movq(rax, Address(rbp, reg2offset_in(src.first())));
1124       __ movq(Address(rsp, reg2offset_out(dst.first())), rax);
1125     } else {
1126       // stack to reg
1127       __ movq(dst.first()->as_Register(), Address(rbp, reg2offset_in(src.first())));
1128     }
1129   } else if (dst.first()->is_stack()) {
1130     // reg to stack
1131     __ movq(Address(rsp, reg2offset_out(dst.first())), src.first()->as_Register());
1132   } else {
1133     if (dst.first() != src.first()) {
1134       __ movq(dst.first()->as_Register(), src.first()->as_Register());
1135     }
1136   }
1137 }
1138 
1139 // An oop arg. Must pass a handle not the oop itself
1140 static void object_move(MacroAssembler* masm,
1141                         OopMap* map,
1142                         int oop_handle_offset,
1143                         int framesize_in_slots,
1144                         VMRegPair src,
1145                         VMRegPair dst,
1146                         bool is_receiver,
1147                         int* receiver_offset) {
1148 
1149   // must pass a handle. First figure out the location we use as a handle
1150 
1151   Register rHandle = dst.first()->is_stack() ? rax : dst.first()->as_Register();
1152 
1153   // See if oop is NULL if it is we need no handle
1154 
1155   if (src.first()->is_stack()) {
1156 
1157     // Oop is already on the stack as an argument
1158     int offset_in_older_frame = src.first()->reg2stack() + SharedRuntime::out_preserve_stack_slots();
1159     map->set_oop(VMRegImpl::stack2reg(offset_in_older_frame + framesize_in_slots));
1160     if (is_receiver) {
1161       *receiver_offset = (offset_in_older_frame + framesize_in_slots) * VMRegImpl::stack_slot_size;
1162     }
1163 
1164     __ cmpptr(Address(rbp, reg2offset_in(src.first())), (int32_t)NULL_WORD);
1165     __ lea(rHandle, Address(rbp, reg2offset_in(src.first())));
1166     // conditionally move a NULL
1167     __ cmovptr(Assembler::equal, rHandle, Address(rbp, reg2offset_in(src.first())));
1168   } else {
1169 
1170     // Oop is in an a register we must store it to the space we reserve
1171     // on the stack for oop_handles and pass a handle if oop is non-NULL
1172 
1173     const Register rOop = src.first()->as_Register();
1174     int oop_slot;
1175     if (rOop == j_rarg0)
1176       oop_slot = 0;
1177     else if (rOop == j_rarg1)
1178       oop_slot = 1;
1179     else if (rOop == j_rarg2)
1180       oop_slot = 2;
1181     else if (rOop == j_rarg3)
1182       oop_slot = 3;
1183     else if (rOop == j_rarg4)
1184       oop_slot = 4;
1185     else {
1186       assert(rOop == j_rarg5, "wrong register");
1187       oop_slot = 5;
1188     }
1189 
1190     oop_slot = oop_slot * VMRegImpl::slots_per_word + oop_handle_offset;
1191     int offset = oop_slot*VMRegImpl::stack_slot_size;
1192 
1193     map->set_oop(VMRegImpl::stack2reg(oop_slot));
1194     // Store oop in handle area, may be NULL
1195     __ movptr(Address(rsp, offset), rOop);
1196     if (is_receiver) {
1197       *receiver_offset = offset;
1198     }
1199 
1200     __ cmpptr(rOop, (int32_t)NULL_WORD);
1201     __ lea(rHandle, Address(rsp, offset));
1202     // conditionally move a NULL from the handle area where it was just stored
1203     __ cmovptr(Assembler::equal, rHandle, Address(rsp, offset));
1204   }
1205 
1206   // If arg is on the stack then place it otherwise it is already in correct reg.
1207   if (dst.first()->is_stack()) {
1208     __ movptr(Address(rsp, reg2offset_out(dst.first())), rHandle);
1209   }
1210 }
1211 
1212 // A float arg may have to do float reg int reg conversion
1213 static void float_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
1214   assert(!src.second()->is_valid() && !dst.second()->is_valid(), "bad float_move");
1215 
1216   // The calling conventions assures us that each VMregpair is either
1217   // all really one physical register or adjacent stack slots.
1218   // This greatly simplifies the cases here compared to sparc.
1219 
1220   if (src.first()->is_stack()) {
1221     if (dst.first()->is_stack()) {
1222       __ movl(rax, Address(rbp, reg2offset_in(src.first())));
1223       __ movptr(Address(rsp, reg2offset_out(dst.first())), rax);
1224     } else {
1225       // stack to reg
1226       assert(dst.first()->is_XMMRegister(), "only expect xmm registers as parameters");
1227       __ movflt(dst.first()->as_XMMRegister(), Address(rbp, reg2offset_in(src.first())));
1228     }
1229   } else if (dst.first()->is_stack()) {
1230     // reg to stack
1231     assert(src.first()->is_XMMRegister(), "only expect xmm registers as parameters");
1232     __ movflt(Address(rsp, reg2offset_out(dst.first())), src.first()->as_XMMRegister());
1233   } else {
1234     // reg to reg
1235     // In theory these overlap but the ordering is such that this is likely a nop
1236     if ( src.first() != dst.first()) {
1237       __ movdbl(dst.first()->as_XMMRegister(),  src.first()->as_XMMRegister());
1238     }
1239   }
1240 }
1241 
1242 // A long move
1243 static void long_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
1244 
1245   // The calling conventions assures us that each VMregpair is either
1246   // all really one physical register or adjacent stack slots.
1247   // This greatly simplifies the cases here compared to sparc.
1248 
1249   if (src.is_single_phys_reg() ) {
1250     if (dst.is_single_phys_reg()) {
1251       if (dst.first() != src.first()) {
1252         __ mov(dst.first()->as_Register(), src.first()->as_Register());
1253       }
1254     } else {
1255       assert(dst.is_single_reg(), "not a stack pair");
1256       __ movq(Address(rsp, reg2offset_out(dst.first())), src.first()->as_Register());
1257     }
1258   } else if (dst.is_single_phys_reg()) {
1259     assert(src.is_single_reg(),  "not a stack pair");
1260     __ movq(dst.first()->as_Register(), Address(rbp, reg2offset_out(src.first())));
1261   } else {
1262     assert(src.is_single_reg() && dst.is_single_reg(), "not stack pairs");
1263     __ movq(rax, Address(rbp, reg2offset_in(src.first())));
1264     __ movq(Address(rsp, reg2offset_out(dst.first())), rax);
1265   }
1266 }
1267 
1268 // A double move
1269 static void double_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
1270 
1271   // The calling conventions assures us that each VMregpair is either
1272   // all really one physical register or adjacent stack slots.
1273   // This greatly simplifies the cases here compared to sparc.
1274 
1275   if (src.is_single_phys_reg() ) {
1276     if (dst.is_single_phys_reg()) {
1277       // In theory these overlap but the ordering is such that this is likely a nop
1278       if ( src.first() != dst.first()) {
1279         __ movdbl(dst.first()->as_XMMRegister(), src.first()->as_XMMRegister());
1280       }
1281     } else {
1282       assert(dst.is_single_reg(), "not a stack pair");
1283       __ movdbl(Address(rsp, reg2offset_out(dst.first())), src.first()->as_XMMRegister());
1284     }
1285   } else if (dst.is_single_phys_reg()) {
1286     assert(src.is_single_reg(),  "not a stack pair");
1287     __ movdbl(dst.first()->as_XMMRegister(), Address(rbp, reg2offset_out(src.first())));
1288   } else {
1289     assert(src.is_single_reg() && dst.is_single_reg(), "not stack pairs");
1290     __ movq(rax, Address(rbp, reg2offset_in(src.first())));
1291     __ movq(Address(rsp, reg2offset_out(dst.first())), rax);
1292   }
1293 }
1294 
1295 
1296 void SharedRuntime::save_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {
1297   // We always ignore the frame_slots arg and just use the space just below frame pointer
1298   // which by this time is free to use
1299   switch (ret_type) {
1300   case T_FLOAT:
1301     __ movflt(Address(rbp, -wordSize), xmm0);
1302     break;
1303   case T_DOUBLE:
1304     __ movdbl(Address(rbp, -wordSize), xmm0);
1305     break;
1306   case T_VOID:  break;
1307   default: {
1308     __ movptr(Address(rbp, -wordSize), rax);
1309     }
1310   }
1311 }
1312 
1313 void SharedRuntime::restore_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {
1314   // We always ignore the frame_slots arg and just use the space just below frame pointer
1315   // which by this time is free to use
1316   switch (ret_type) {
1317   case T_FLOAT:
1318     __ movflt(xmm0, Address(rbp, -wordSize));
1319     break;
1320   case T_DOUBLE:
1321     __ movdbl(xmm0, Address(rbp, -wordSize));
1322     break;
1323   case T_VOID:  break;
1324   default: {
1325     __ movptr(rax, Address(rbp, -wordSize));
1326     }
1327   }
1328 }
1329 
1330 static void save_args(MacroAssembler *masm, int arg_count, int first_arg, VMRegPair *args) {
1331     for ( int i = first_arg ; i < arg_count ; i++ ) {
1332       if (args[i].first()->is_Register()) {
1333         __ push(args[i].first()->as_Register());
1334       } else if (args[i].first()->is_XMMRegister()) {
1335         __ subptr(rsp, 2*wordSize);
1336         __ movdbl(Address(rsp, 0), args[i].first()->as_XMMRegister());
1337       }
1338     }
1339 }
1340 
1341 static void restore_args(MacroAssembler *masm, int arg_count, int first_arg, VMRegPair *args) {
1342     for ( int i = arg_count - 1 ; i >= first_arg ; i-- ) {
1343       if (args[i].first()->is_Register()) {
1344         __ pop(args[i].first()->as_Register());
1345       } else if (args[i].first()->is_XMMRegister()) {
1346         __ movdbl(args[i].first()->as_XMMRegister(), Address(rsp, 0));
1347         __ addptr(rsp, 2*wordSize);
1348       }
1349     }
1350 }
1351 
1352 
1353 static void save_or_restore_arguments(MacroAssembler* masm,
1354                                       const int stack_slots,
1355                                       const int total_in_args,
1356                                       const int arg_save_area,
1357                                       OopMap* map,
1358                                       VMRegPair* in_regs,
1359                                       BasicType* in_sig_bt) {
1360   // if map is non-NULL then the code should store the values,
1361   // otherwise it should load them.
1362   int slot = arg_save_area;
1363   // Save down double word first
1364   for ( int i = 0; i < total_in_args; i++) {
1365     if (in_regs[i].first()->is_XMMRegister() && in_sig_bt[i] == T_DOUBLE) {
1366       int offset = slot * VMRegImpl::stack_slot_size;
1367       slot += VMRegImpl::slots_per_word;
1368       assert(slot <= stack_slots, "overflow");
1369       if (map != NULL) {
1370         __ movdbl(Address(rsp, offset), in_regs[i].first()->as_XMMRegister());
1371       } else {
1372         __ movdbl(in_regs[i].first()->as_XMMRegister(), Address(rsp, offset));
1373       }
1374     }
1375     if (in_regs[i].first()->is_Register() &&
1376         (in_sig_bt[i] == T_LONG || in_sig_bt[i] == T_ARRAY)) {
1377       int offset = slot * VMRegImpl::stack_slot_size;
1378       if (map != NULL) {
1379         __ movq(Address(rsp, offset), in_regs[i].first()->as_Register());
1380         if (in_sig_bt[i] == T_ARRAY) {
1381           map->set_oop(VMRegImpl::stack2reg(slot));;
1382         }
1383       } else {
1384         __ movq(in_regs[i].first()->as_Register(), Address(rsp, offset));
1385       }
1386       slot += VMRegImpl::slots_per_word;
1387     }
1388   }
1389   // Save or restore single word registers
1390   for ( int i = 0; i < total_in_args; i++) {
1391     if (in_regs[i].first()->is_Register()) {
1392       int offset = slot * VMRegImpl::stack_slot_size;
1393       slot++;
1394       assert(slot <= stack_slots, "overflow");
1395 
1396       // Value is in an input register pass we must flush it to the stack
1397       const Register reg = in_regs[i].first()->as_Register();
1398       switch (in_sig_bt[i]) {
1399         case T_BOOLEAN:
1400         case T_CHAR:
1401         case T_BYTE:
1402         case T_SHORT:
1403         case T_INT:
1404           if (map != NULL) {
1405             __ movl(Address(rsp, offset), reg);
1406           } else {
1407             __ movl(reg, Address(rsp, offset));
1408           }
1409           break;
1410         case T_ARRAY:
1411         case T_LONG:
1412           // handled above
1413           break;
1414         case T_OBJECT:
1415         default: ShouldNotReachHere();
1416       }
1417     } else if (in_regs[i].first()->is_XMMRegister()) {
1418       if (in_sig_bt[i] == T_FLOAT) {
1419         int offset = slot * VMRegImpl::stack_slot_size;
1420         slot++;
1421         assert(slot <= stack_slots, "overflow");
1422         if (map != NULL) {
1423           __ movflt(Address(rsp, offset), in_regs[i].first()->as_XMMRegister());
1424         } else {
1425           __ movflt(in_regs[i].first()->as_XMMRegister(), Address(rsp, offset));
1426         }
1427       }
1428     } else if (in_regs[i].first()->is_stack()) {
1429       if (in_sig_bt[i] == T_ARRAY && map != NULL) {
1430         int offset_in_older_frame = in_regs[i].first()->reg2stack() + SharedRuntime::out_preserve_stack_slots();
1431         map->set_oop(VMRegImpl::stack2reg(offset_in_older_frame + stack_slots));
1432       }
1433     }
1434   }
1435 }
1436 
1437 
1438 // Check GCLocker::needs_gc and enter the runtime if it's true.  This
1439 // keeps a new JNI critical region from starting until a GC has been
1440 // forced.  Save down any oops in registers and describe them in an
1441 // OopMap.
1442 static void check_needs_gc_for_critical_native(MacroAssembler* masm,
1443                                                int stack_slots,
1444                                                int total_c_args,
1445                                                int total_in_args,
1446                                                int arg_save_area,
1447                                                OopMapSet* oop_maps,
1448                                                VMRegPair* in_regs,
1449                                                BasicType* in_sig_bt) {
1450   __ block_comment("check GCLocker::needs_gc");
1451   Label cont;
1452   __ cmp8(ExternalAddress((address)GCLocker::needs_gc_address()), false);
1453   __ jcc(Assembler::equal, cont);
1454 
1455   // Save down any incoming oops and call into the runtime to halt for a GC
1456 
1457   OopMap* map = new OopMap(stack_slots * 2, 0 /* arg_slots*/);
1458   save_or_restore_arguments(masm, stack_slots, total_in_args,
1459                             arg_save_area, map, in_regs, in_sig_bt);
1460 
1461   address the_pc = __ pc();
1462   oop_maps->add_gc_map( __ offset(), map);
1463   __ set_last_Java_frame(rsp, noreg, the_pc);
1464 
1465   __ block_comment("block_for_jni_critical");
1466   __ movptr(c_rarg0, r15_thread);
1467   __ mov(r12, rsp); // remember sp
1468   __ subptr(rsp, frame::arg_reg_save_area_bytes); // windows
1469   __ andptr(rsp, -16); // align stack as required by ABI
1470   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::block_for_jni_critical)));
1471   __ mov(rsp, r12); // restore sp
1472   __ reinit_heapbase();
1473 
1474   __ reset_last_Java_frame(false);
1475 
1476   save_or_restore_arguments(masm, stack_slots, total_in_args,
1477                             arg_save_area, NULL, in_regs, in_sig_bt);
1478   __ bind(cont);
1479 #ifdef ASSERT
1480   if (StressCriticalJNINatives) {
1481     // Stress register saving
1482     OopMap* map = new OopMap(stack_slots * 2, 0 /* arg_slots*/);
1483     save_or_restore_arguments(masm, stack_slots, total_in_args,
1484                               arg_save_area, map, in_regs, in_sig_bt);
1485     // Destroy argument registers
1486     for (int i = 0; i < total_in_args - 1; i++) {
1487       if (in_regs[i].first()->is_Register()) {
1488         const Register reg = in_regs[i].first()->as_Register();
1489         __ xorptr(reg, reg);
1490       } else if (in_regs[i].first()->is_XMMRegister()) {
1491         __ xorpd(in_regs[i].first()->as_XMMRegister(), in_regs[i].first()->as_XMMRegister());
1492       } else if (in_regs[i].first()->is_FloatRegister()) {
1493         ShouldNotReachHere();
1494       } else if (in_regs[i].first()->is_stack()) {
1495         // Nothing to do
1496       } else {
1497         ShouldNotReachHere();
1498       }
1499       if (in_sig_bt[i] == T_LONG || in_sig_bt[i] == T_DOUBLE) {
1500         i++;
1501       }
1502     }
1503 
1504     save_or_restore_arguments(masm, stack_slots, total_in_args,
1505                               arg_save_area, NULL, in_regs, in_sig_bt);
1506   }
1507 #endif
1508 }
1509 
1510 // Unpack an array argument into a pointer to the body and the length
1511 // if the array is non-null, otherwise pass 0 for both.
1512 static void unpack_array_argument(MacroAssembler* masm, VMRegPair reg, BasicType in_elem_type, VMRegPair body_arg, VMRegPair length_arg) {
1513   Register tmp_reg = rax;
1514   assert(!body_arg.first()->is_Register() || body_arg.first()->as_Register() != tmp_reg,
1515          "possible collision");
1516   assert(!length_arg.first()->is_Register() || length_arg.first()->as_Register() != tmp_reg,
1517          "possible collision");
1518 
1519   __ block_comment("unpack_array_argument {");
1520 
1521   // Pass the length, ptr pair
1522   Label is_null, done;
1523   VMRegPair tmp;
1524   tmp.set_ptr(tmp_reg->as_VMReg());
1525   if (reg.first()->is_stack()) {
1526     // Load the arg up from the stack
1527     move_ptr(masm, reg, tmp);
1528     reg = tmp;
1529   }
1530   __ testptr(reg.first()->as_Register(), reg.first()->as_Register());
1531   __ jccb(Assembler::equal, is_null);
1532   __ lea(tmp_reg, Address(reg.first()->as_Register(), arrayOopDesc::base_offset_in_bytes(in_elem_type)));
1533   move_ptr(masm, tmp, body_arg);
1534   // load the length relative to the body.
1535   __ movl(tmp_reg, Address(tmp_reg, arrayOopDesc::length_offset_in_bytes() -
1536                            arrayOopDesc::base_offset_in_bytes(in_elem_type)));
1537   move32_64(masm, tmp, length_arg);
1538   __ jmpb(done);
1539   __ bind(is_null);
1540   // Pass zeros
1541   __ xorptr(tmp_reg, tmp_reg);
1542   move_ptr(masm, tmp, body_arg);
1543   move32_64(masm, tmp, length_arg);
1544   __ bind(done);
1545 
1546   __ block_comment("} unpack_array_argument");
1547 }
1548 
1549 
1550 // Different signatures may require very different orders for the move
1551 // to avoid clobbering other arguments.  There's no simple way to
1552 // order them safely.  Compute a safe order for issuing stores and
1553 // break any cycles in those stores.  This code is fairly general but
1554 // it's not necessary on the other platforms so we keep it in the
1555 // platform dependent code instead of moving it into a shared file.
1556 // (See bugs 7013347 & 7145024.)
1557 // Note that this code is specific to LP64.
1558 class ComputeMoveOrder: public StackObj {
1559   class MoveOperation: public ResourceObj {
1560     friend class ComputeMoveOrder;
1561    private:
1562     VMRegPair        _src;
1563     VMRegPair        _dst;
1564     int              _src_index;
1565     int              _dst_index;
1566     bool             _processed;
1567     MoveOperation*  _next;
1568     MoveOperation*  _prev;
1569 
1570     static int get_id(VMRegPair r) {
1571       return r.first()->value();
1572     }
1573 
1574    public:
1575     MoveOperation(int src_index, VMRegPair src, int dst_index, VMRegPair dst):
1576       _src(src)
1577     , _src_index(src_index)
1578     , _dst(dst)
1579     , _dst_index(dst_index)
1580     , _next(NULL)
1581     , _prev(NULL)
1582     , _processed(false) {
1583     }
1584 
1585     VMRegPair src() const              { return _src; }
1586     int src_id() const                 { return get_id(src()); }
1587     int src_index() const              { return _src_index; }
1588     VMRegPair dst() const              { return _dst; }
1589     void set_dst(int i, VMRegPair dst) { _dst_index = i, _dst = dst; }
1590     int dst_index() const              { return _dst_index; }
1591     int dst_id() const                 { return get_id(dst()); }
1592     MoveOperation* next() const       { return _next; }
1593     MoveOperation* prev() const       { return _prev; }
1594     void set_processed()               { _processed = true; }
1595     bool is_processed() const          { return _processed; }
1596 
1597     // insert
1598     void break_cycle(VMRegPair temp_register) {
1599       // create a new store following the last store
1600       // to move from the temp_register to the original
1601       MoveOperation* new_store = new MoveOperation(-1, temp_register, dst_index(), dst());
1602 
1603       // break the cycle of links and insert new_store at the end
1604       // break the reverse link.
1605       MoveOperation* p = prev();
1606       assert(p->next() == this, "must be");
1607       _prev = NULL;
1608       p->_next = new_store;
1609       new_store->_prev = p;
1610 
1611       // change the original store to save it's value in the temp.
1612       set_dst(-1, temp_register);
1613     }
1614 
1615     void link(GrowableArray<MoveOperation*>& killer) {
1616       // link this store in front the store that it depends on
1617       MoveOperation* n = killer.at_grow(src_id(), NULL);
1618       if (n != NULL) {
1619         assert(_next == NULL && n->_prev == NULL, "shouldn't have been set yet");
1620         _next = n;
1621         n->_prev = this;
1622       }
1623     }
1624   };
1625 
1626  private:
1627   GrowableArray<MoveOperation*> edges;
1628 
1629  public:
1630   ComputeMoveOrder(int total_in_args, VMRegPair* in_regs, int total_c_args, VMRegPair* out_regs,
1631                     BasicType* in_sig_bt, GrowableArray<int>& arg_order, VMRegPair tmp_vmreg) {
1632     // Move operations where the dest is the stack can all be
1633     // scheduled first since they can't interfere with the other moves.
1634     for (int i = total_in_args - 1, c_arg = total_c_args - 1; i >= 0; i--, c_arg--) {
1635       if (in_sig_bt[i] == T_ARRAY) {
1636         c_arg--;
1637         if (out_regs[c_arg].first()->is_stack() &&
1638             out_regs[c_arg + 1].first()->is_stack()) {
1639           arg_order.push(i);
1640           arg_order.push(c_arg);
1641         } else {
1642           if (out_regs[c_arg].first()->is_stack() ||
1643               in_regs[i].first() == out_regs[c_arg].first()) {
1644             add_edge(i, in_regs[i].first(), c_arg, out_regs[c_arg + 1]);
1645           } else {
1646             add_edge(i, in_regs[i].first(), c_arg, out_regs[c_arg]);
1647           }
1648         }
1649       } else if (in_sig_bt[i] == T_VOID) {
1650         arg_order.push(i);
1651         arg_order.push(c_arg);
1652       } else {
1653         if (out_regs[c_arg].first()->is_stack() ||
1654             in_regs[i].first() == out_regs[c_arg].first()) {
1655           arg_order.push(i);
1656           arg_order.push(c_arg);
1657         } else {
1658           add_edge(i, in_regs[i].first(), c_arg, out_regs[c_arg]);
1659         }
1660       }
1661     }
1662     // Break any cycles in the register moves and emit the in the
1663     // proper order.
1664     GrowableArray<MoveOperation*>* stores = get_store_order(tmp_vmreg);
1665     for (int i = 0; i < stores->length(); i++) {
1666       arg_order.push(stores->at(i)->src_index());
1667       arg_order.push(stores->at(i)->dst_index());
1668     }
1669  }
1670 
1671   // Collected all the move operations
1672   void add_edge(int src_index, VMRegPair src, int dst_index, VMRegPair dst) {
1673     if (src.first() == dst.first()) return;
1674     edges.append(new MoveOperation(src_index, src, dst_index, dst));
1675   }
1676 
1677   // Walk the edges breaking cycles between moves.  The result list
1678   // can be walked in order to produce the proper set of loads
1679   GrowableArray<MoveOperation*>* get_store_order(VMRegPair temp_register) {
1680     // Record which moves kill which values
1681     GrowableArray<MoveOperation*> killer;
1682     for (int i = 0; i < edges.length(); i++) {
1683       MoveOperation* s = edges.at(i);
1684       assert(killer.at_grow(s->dst_id(), NULL) == NULL, "only one killer");
1685       killer.at_put_grow(s->dst_id(), s, NULL);
1686     }
1687     assert(killer.at_grow(MoveOperation::get_id(temp_register), NULL) == NULL,
1688            "make sure temp isn't in the registers that are killed");
1689 
1690     // create links between loads and stores
1691     for (int i = 0; i < edges.length(); i++) {
1692       edges.at(i)->link(killer);
1693     }
1694 
1695     // at this point, all the move operations are chained together
1696     // in a doubly linked list.  Processing it backwards finds
1697     // the beginning of the chain, forwards finds the end.  If there's
1698     // a cycle it can be broken at any point,  so pick an edge and walk
1699     // backward until the list ends or we end where we started.
1700     GrowableArray<MoveOperation*>* stores = new GrowableArray<MoveOperation*>();
1701     for (int e = 0; e < edges.length(); e++) {
1702       MoveOperation* s = edges.at(e);
1703       if (!s->is_processed()) {
1704         MoveOperation* start = s;
1705         // search for the beginning of the chain or cycle
1706         while (start->prev() != NULL && start->prev() != s) {
1707           start = start->prev();
1708         }
1709         if (start->prev() == s) {
1710           start->break_cycle(temp_register);
1711         }
1712         // walk the chain forward inserting to store list
1713         while (start != NULL) {
1714           stores->append(start);
1715           start->set_processed();
1716           start = start->next();
1717         }
1718       }
1719     }
1720     return stores;
1721   }
1722 };
1723 
1724 static void verify_oop_args(MacroAssembler* masm,
1725                             const methodHandle& method,
1726                             const BasicType* sig_bt,
1727                             const VMRegPair* regs) {
1728   Register temp_reg = rbx;  // not part of any compiled calling seq
1729   if (VerifyOops) {
1730     for (int i = 0; i < method->size_of_parameters(); i++) {
1731       if (sig_bt[i] == T_OBJECT ||
1732           sig_bt[i] == T_ARRAY) {
1733         VMReg r = regs[i].first();
1734         assert(r->is_valid(), "bad oop arg");
1735         if (r->is_stack()) {
1736           __ movptr(temp_reg, Address(rsp, r->reg2stack() * VMRegImpl::stack_slot_size + wordSize));
1737           __ verify_oop(temp_reg);
1738         } else {
1739           __ verify_oop(r->as_Register());
1740         }
1741       }
1742     }
1743   }
1744 }
1745 
1746 static void gen_special_dispatch(MacroAssembler* masm,
1747                                  const methodHandle& method,
1748                                  const BasicType* sig_bt,
1749                                  const VMRegPair* regs) {
1750   verify_oop_args(masm, method, sig_bt, regs);
1751   vmIntrinsics::ID iid = method->intrinsic_id();
1752 
1753   // Now write the args into the outgoing interpreter space
1754   bool     has_receiver   = false;
1755   Register receiver_reg   = noreg;
1756   int      member_arg_pos = -1;
1757   Register member_reg     = noreg;
1758   int      ref_kind       = MethodHandles::signature_polymorphic_intrinsic_ref_kind(iid);
1759   if (ref_kind != 0) {
1760     member_arg_pos = method->size_of_parameters() - 1;  // trailing MemberName argument
1761     member_reg = rbx;  // known to be free at this point
1762     has_receiver = MethodHandles::ref_kind_has_receiver(ref_kind);
1763   } else if (iid == vmIntrinsics::_invokeBasic) {
1764     has_receiver = true;
1765   } else {
1766     fatal("unexpected intrinsic id %d", iid);
1767   }
1768 
1769   if (member_reg != noreg) {
1770     // Load the member_arg into register, if necessary.
1771     SharedRuntime::check_member_name_argument_is_last_argument(method, sig_bt, regs);
1772     VMReg r = regs[member_arg_pos].first();
1773     if (r->is_stack()) {
1774       __ movptr(member_reg, Address(rsp, r->reg2stack() * VMRegImpl::stack_slot_size + wordSize));
1775     } else {
1776       // no data motion is needed
1777       member_reg = r->as_Register();
1778     }
1779   }
1780 
1781   if (has_receiver) {
1782     // Make sure the receiver is loaded into a register.
1783     assert(method->size_of_parameters() > 0, "oob");
1784     assert(sig_bt[0] == T_OBJECT, "receiver argument must be an object");
1785     VMReg r = regs[0].first();
1786     assert(r->is_valid(), "bad receiver arg");
1787     if (r->is_stack()) {
1788       // Porting note:  This assumes that compiled calling conventions always
1789       // pass the receiver oop in a register.  If this is not true on some
1790       // platform, pick a temp and load the receiver from stack.
1791       fatal("receiver always in a register");
1792       receiver_reg = j_rarg0;  // known to be free at this point
1793       __ movptr(receiver_reg, Address(rsp, r->reg2stack() * VMRegImpl::stack_slot_size + wordSize));
1794     } else {
1795       // no data motion is needed
1796       receiver_reg = r->as_Register();
1797     }
1798   }
1799 
1800   // Figure out which address we are really jumping to:
1801   MethodHandles::generate_method_handle_dispatch(masm, iid,
1802                                                  receiver_reg, member_reg, /*for_compiler_entry:*/ true);
1803 }
1804 
1805 // ---------------------------------------------------------------------------
1806 // Generate a native wrapper for a given method.  The method takes arguments
1807 // in the Java compiled code convention, marshals them to the native
1808 // convention (handlizes oops, etc), transitions to native, makes the call,
1809 // returns to java state (possibly blocking), unhandlizes any result and
1810 // returns.
1811 //
1812 // Critical native functions are a shorthand for the use of
1813 // GetPrimtiveArrayCritical and disallow the use of any other JNI
1814 // functions.  The wrapper is expected to unpack the arguments before
1815 // passing them to the callee and perform checks before and after the
1816 // native call to ensure that they GCLocker
1817 // lock_critical/unlock_critical semantics are followed.  Some other
1818 // parts of JNI setup are skipped like the tear down of the JNI handle
1819 // block and the check for pending exceptions it's impossible for them
1820 // to be thrown.
1821 //
1822 // They are roughly structured like this:
1823 //    if (GCLocker::needs_gc())
1824 //      SharedRuntime::block_for_jni_critical();
1825 //    tranistion to thread_in_native
1826 //    unpack arrray arguments and call native entry point
1827 //    check for safepoint in progress
1828 //    check if any thread suspend flags are set
1829 //      call into JVM and possible unlock the JNI critical
1830 //      if a GC was suppressed while in the critical native.
1831 //    transition back to thread_in_Java
1832 //    return to caller
1833 //
1834 nmethod* SharedRuntime::generate_native_wrapper(MacroAssembler* masm,
1835                                                 const methodHandle& method,
1836                                                 int compile_id,
1837                                                 BasicType* in_sig_bt,
1838                                                 VMRegPair* in_regs,
1839                                                 BasicType ret_type) {
1840   if (method->is_method_handle_intrinsic()) {
1841     vmIntrinsics::ID iid = method->intrinsic_id();
1842     intptr_t start = (intptr_t)__ pc();
1843     int vep_offset = ((intptr_t)__ pc()) - start;
1844     gen_special_dispatch(masm,
1845                          method,
1846                          in_sig_bt,
1847                          in_regs);
1848     int frame_complete = ((intptr_t)__ pc()) - start;  // not complete, period
1849     __ flush();
1850     int stack_slots = SharedRuntime::out_preserve_stack_slots();  // no out slots at all, actually
1851     return nmethod::new_native_nmethod(method,
1852                                        compile_id,
1853                                        masm->code(),
1854                                        vep_offset,
1855                                        frame_complete,
1856                                        stack_slots / VMRegImpl::slots_per_word,
1857                                        in_ByteSize(-1),
1858                                        in_ByteSize(-1),
1859                                        (OopMapSet*)NULL);
1860   }
1861   bool is_critical_native = true;
1862   address native_func = method->critical_native_function();
1863   if (native_func == NULL) {
1864     native_func = method->native_function();
1865     is_critical_native = false;
1866   }
1867   assert(native_func != NULL, "must have function");
1868 
1869   // An OopMap for lock (and class if static)
1870   OopMapSet *oop_maps = new OopMapSet();
1871   intptr_t start = (intptr_t)__ pc();
1872 
1873   // We have received a description of where all the java arg are located
1874   // on entry to the wrapper. We need to convert these args to where
1875   // the jni function will expect them. To figure out where they go
1876   // we convert the java signature to a C signature by inserting
1877   // the hidden arguments as arg[0] and possibly arg[1] (static method)
1878 
1879   const int total_in_args = method->size_of_parameters();
1880   int total_c_args = total_in_args;
1881   if (!is_critical_native) {
1882     total_c_args += 1;
1883     if (method->is_static()) {
1884       total_c_args++;
1885     }
1886   } else {
1887     for (int i = 0; i < total_in_args; i++) {
1888       if (in_sig_bt[i] == T_ARRAY) {
1889         total_c_args++;
1890       }
1891     }
1892   }
1893 
1894   BasicType* out_sig_bt = NEW_RESOURCE_ARRAY(BasicType, total_c_args);
1895   VMRegPair* out_regs   = NEW_RESOURCE_ARRAY(VMRegPair, total_c_args);
1896   BasicType* in_elem_bt = NULL;
1897 
1898   int argc = 0;
1899   if (!is_critical_native) {
1900     out_sig_bt[argc++] = T_ADDRESS;
1901     if (method->is_static()) {
1902       out_sig_bt[argc++] = T_OBJECT;
1903     }
1904 
1905     for (int i = 0; i < total_in_args ; i++ ) {
1906       out_sig_bt[argc++] = in_sig_bt[i];
1907     }
1908   } else {
1909     Thread* THREAD = Thread::current();
1910     in_elem_bt = NEW_RESOURCE_ARRAY(BasicType, total_in_args);
1911     SignatureStream ss(method->signature());
1912     for (int i = 0; i < total_in_args ; i++ ) {
1913       if (in_sig_bt[i] == T_ARRAY) {
1914         // Arrays are passed as int, elem* pair
1915         out_sig_bt[argc++] = T_INT;
1916         out_sig_bt[argc++] = T_ADDRESS;
1917         Symbol* atype = ss.as_symbol(CHECK_NULL);
1918         const char* at = atype->as_C_string();
1919         if (strlen(at) == 2) {
1920           assert(at[0] == '[', "must be");
1921           switch (at[1]) {
1922             case 'B': in_elem_bt[i]  = T_BYTE; break;
1923             case 'C': in_elem_bt[i]  = T_CHAR; break;
1924             case 'D': in_elem_bt[i]  = T_DOUBLE; break;
1925             case 'F': in_elem_bt[i]  = T_FLOAT; break;
1926             case 'I': in_elem_bt[i]  = T_INT; break;
1927             case 'J': in_elem_bt[i]  = T_LONG; break;
1928             case 'S': in_elem_bt[i]  = T_SHORT; break;
1929             case 'Z': in_elem_bt[i]  = T_BOOLEAN; break;
1930             default: ShouldNotReachHere();
1931           }
1932         }
1933       } else {
1934         out_sig_bt[argc++] = in_sig_bt[i];
1935         in_elem_bt[i] = T_VOID;
1936       }
1937       if (in_sig_bt[i] != T_VOID) {
1938         assert(in_sig_bt[i] == ss.type(), "must match");
1939         ss.next();
1940       }
1941     }
1942   }
1943 
1944   // Now figure out where the args must be stored and how much stack space
1945   // they require.
1946   int out_arg_slots;
1947   out_arg_slots = c_calling_convention(out_sig_bt, out_regs, NULL, total_c_args);
1948 
1949   // Compute framesize for the wrapper.  We need to handlize all oops in
1950   // incoming registers
1951 
1952   // Calculate the total number of stack slots we will need.
1953 
1954   // First count the abi requirement plus all of the outgoing args
1955   int stack_slots = SharedRuntime::out_preserve_stack_slots() + out_arg_slots;
1956 
1957   // Now the space for the inbound oop handle area
1958   int total_save_slots = 6 * VMRegImpl::slots_per_word;  // 6 arguments passed in registers
1959   if (is_critical_native) {
1960     // Critical natives may have to call out so they need a save area
1961     // for register arguments.
1962     int double_slots = 0;
1963     int single_slots = 0;
1964     for ( int i = 0; i < total_in_args; i++) {
1965       if (in_regs[i].first()->is_Register()) {
1966         const Register reg = in_regs[i].first()->as_Register();
1967         switch (in_sig_bt[i]) {
1968           case T_BOOLEAN:
1969           case T_BYTE:
1970           case T_SHORT:
1971           case T_CHAR:
1972           case T_INT:  single_slots++; break;
1973           case T_ARRAY:  // specific to LP64 (7145024)
1974           case T_LONG: double_slots++; break;
1975           default:  ShouldNotReachHere();
1976         }
1977       } else if (in_regs[i].first()->is_XMMRegister()) {
1978         switch (in_sig_bt[i]) {
1979           case T_FLOAT:  single_slots++; break;
1980           case T_DOUBLE: double_slots++; break;
1981           default:  ShouldNotReachHere();
1982         }
1983       } else if (in_regs[i].first()->is_FloatRegister()) {
1984         ShouldNotReachHere();
1985       }
1986     }
1987     total_save_slots = double_slots * 2 + single_slots;
1988     // align the save area
1989     if (double_slots != 0) {
1990       stack_slots = align_up(stack_slots, 2);
1991     }
1992   }
1993 
1994   int oop_handle_offset = stack_slots;
1995   stack_slots += total_save_slots;
1996 
1997   // Now any space we need for handlizing a klass if static method
1998 
1999   int klass_slot_offset = 0;
2000   int klass_offset = -1;
2001   int lock_slot_offset = 0;
2002   bool is_static = false;
2003 
2004   if (method->is_static()) {
2005     klass_slot_offset = stack_slots;
2006     stack_slots += VMRegImpl::slots_per_word;
2007     klass_offset = klass_slot_offset * VMRegImpl::stack_slot_size;
2008     is_static = true;
2009   }
2010 
2011   // Plus a lock if needed
2012 
2013   if (method->is_synchronized()) {
2014     lock_slot_offset = stack_slots;
2015     stack_slots += VMRegImpl::slots_per_word;
2016   }
2017 
2018   // Now a place (+2) to save return values or temp during shuffling
2019   // + 4 for return address (which we own) and saved rbp
2020   stack_slots += 6;
2021 
2022   // Ok The space we have allocated will look like:
2023   //
2024   //
2025   // FP-> |                     |
2026   //      |---------------------|
2027   //      | 2 slots for moves   |
2028   //      |---------------------|
2029   //      | lock box (if sync)  |
2030   //      |---------------------| <- lock_slot_offset
2031   //      | klass (if static)   |
2032   //      |---------------------| <- klass_slot_offset
2033   //      | oopHandle area      |
2034   //      |---------------------| <- oop_handle_offset (6 java arg registers)
2035   //      | outbound memory     |
2036   //      | based arguments     |
2037   //      |                     |
2038   //      |---------------------|
2039   //      |                     |
2040   // SP-> | out_preserved_slots |
2041   //
2042   //
2043 
2044 
2045   // Now compute actual number of stack words we need rounding to make
2046   // stack properly aligned.
2047   stack_slots = align_up(stack_slots, StackAlignmentInSlots);
2048 
2049   int stack_size = stack_slots * VMRegImpl::stack_slot_size;
2050 
2051   // First thing make an ic check to see if we should even be here
2052 
2053   // We are free to use all registers as temps without saving them and
2054   // restoring them except rbp. rbp is the only callee save register
2055   // as far as the interpreter and the compiler(s) are concerned.
2056 
2057 
2058   const Register ic_reg = rax;
2059   const Register receiver = j_rarg0;
2060 
2061   Label hit;
2062   Label exception_pending;
2063 
2064   assert_different_registers(ic_reg, receiver, rscratch1);
2065   __ verify_oop(receiver);
2066   __ load_klass(rscratch1, receiver);
2067   __ cmpq(ic_reg, rscratch1);
2068   __ jcc(Assembler::equal, hit);
2069 
2070   __ jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
2071 
2072   // Verified entry point must be aligned
2073   __ align(8);
2074 
2075   __ bind(hit);
2076 
2077   int vep_offset = ((intptr_t)__ pc()) - start;
2078 
2079 #ifdef COMPILER1
2080   // For Object.hashCode, System.identityHashCode try to pull hashCode from object header if available.
2081   if ((InlineObjectHash && method->intrinsic_id() == vmIntrinsics::_hashCode) || (method->intrinsic_id() == vmIntrinsics::_identityHashCode)) {
2082     inline_check_hashcode_from_object_header(masm, method, j_rarg0 /*obj_reg*/, rax /*result*/);
2083   }
2084 #endif // COMPILER1
2085 
2086   // The instruction at the verified entry point must be 5 bytes or longer
2087   // because it can be patched on the fly by make_non_entrant. The stack bang
2088   // instruction fits that requirement.
2089 
2090   // Generate stack overflow check
2091 
2092   if (UseStackBanging) {
2093     __ bang_stack_with_offset((int)JavaThread::stack_shadow_zone_size());
2094   } else {
2095     // need a 5 byte instruction to allow MT safe patching to non-entrant
2096     __ fat_nop();
2097   }
2098 
2099   // Generate a new frame for the wrapper.
2100   __ enter();
2101   // -2 because return address is already present and so is saved rbp
2102   __ subptr(rsp, stack_size - 2*wordSize);
2103 
2104   // Frame is now completed as far as size and linkage.
2105   int frame_complete = ((intptr_t)__ pc()) - start;
2106 
2107     if (UseRTMLocking) {
2108       // Abort RTM transaction before calling JNI
2109       // because critical section will be large and will be
2110       // aborted anyway. Also nmethod could be deoptimized.
2111       __ xabort(0);
2112     }
2113 
2114 #ifdef ASSERT
2115     {
2116       Label L;
2117       __ mov(rax, rsp);
2118       __ andptr(rax, -16); // must be 16 byte boundary (see amd64 ABI)
2119       __ cmpptr(rax, rsp);
2120       __ jcc(Assembler::equal, L);
2121       __ stop("improperly aligned stack");
2122       __ bind(L);
2123     }
2124 #endif /* ASSERT */
2125 
2126 
2127   // We use r14 as the oop handle for the receiver/klass
2128   // It is callee save so it survives the call to native
2129 
2130   const Register oop_handle_reg = r14;
2131 
2132   if (is_critical_native) {
2133     check_needs_gc_for_critical_native(masm, stack_slots, total_c_args, total_in_args,
2134                                        oop_handle_offset, oop_maps, in_regs, in_sig_bt);
2135   }
2136 
2137   //
2138   // We immediately shuffle the arguments so that any vm call we have to
2139   // make from here on out (sync slow path, jvmti, etc.) we will have
2140   // captured the oops from our caller and have a valid oopMap for
2141   // them.
2142 
2143   // -----------------
2144   // The Grand Shuffle
2145 
2146   // The Java calling convention is either equal (linux) or denser (win64) than the
2147   // c calling convention. However the because of the jni_env argument the c calling
2148   // convention always has at least one more (and two for static) arguments than Java.
2149   // Therefore if we move the args from java -> c backwards then we will never have
2150   // a register->register conflict and we don't have to build a dependency graph
2151   // and figure out how to break any cycles.
2152   //
2153 
2154   // Record esp-based slot for receiver on stack for non-static methods
2155   int receiver_offset = -1;
2156 
2157   // This is a trick. We double the stack slots so we can claim
2158   // the oops in the caller's frame. Since we are sure to have
2159   // more args than the caller doubling is enough to make
2160   // sure we can capture all the incoming oop args from the
2161   // caller.
2162   //
2163   OopMap* map = new OopMap(stack_slots * 2, 0 /* arg_slots*/);
2164 
2165   // Mark location of rbp (someday)
2166   // map->set_callee_saved(VMRegImpl::stack2reg( stack_slots - 2), stack_slots * 2, 0, vmreg(rbp));
2167 
2168   // Use eax, ebx as temporaries during any memory-memory moves we have to do
2169   // All inbound args are referenced based on rbp and all outbound args via rsp.
2170 
2171 
2172 #ifdef ASSERT
2173   bool reg_destroyed[RegisterImpl::number_of_registers];
2174   bool freg_destroyed[XMMRegisterImpl::number_of_registers];
2175   for ( int r = 0 ; r < RegisterImpl::number_of_registers ; r++ ) {
2176     reg_destroyed[r] = false;
2177   }
2178   for ( int f = 0 ; f < XMMRegisterImpl::number_of_registers ; f++ ) {
2179     freg_destroyed[f] = false;
2180   }
2181 
2182 #endif /* ASSERT */
2183 
2184   // This may iterate in two different directions depending on the
2185   // kind of native it is.  The reason is that for regular JNI natives
2186   // the incoming and outgoing registers are offset upwards and for
2187   // critical natives they are offset down.
2188   GrowableArray<int> arg_order(2 * total_in_args);
2189   VMRegPair tmp_vmreg;
2190   tmp_vmreg.set2(rbx->as_VMReg());
2191 
2192   if (!is_critical_native) {
2193     for (int i = total_in_args - 1, c_arg = total_c_args - 1; i >= 0; i--, c_arg--) {
2194       arg_order.push(i);
2195       arg_order.push(c_arg);
2196     }
2197   } else {
2198     // Compute a valid move order, using tmp_vmreg to break any cycles
2199     ComputeMoveOrder cmo(total_in_args, in_regs, total_c_args, out_regs, in_sig_bt, arg_order, tmp_vmreg);
2200   }
2201 
2202   int temploc = -1;
2203   for (int ai = 0; ai < arg_order.length(); ai += 2) {
2204     int i = arg_order.at(ai);
2205     int c_arg = arg_order.at(ai + 1);
2206     __ block_comment(err_msg("move %d -> %d", i, c_arg));
2207     if (c_arg == -1) {
2208       assert(is_critical_native, "should only be required for critical natives");
2209       // This arg needs to be moved to a temporary
2210       __ mov(tmp_vmreg.first()->as_Register(), in_regs[i].first()->as_Register());
2211       in_regs[i] = tmp_vmreg;
2212       temploc = i;
2213       continue;
2214     } else if (i == -1) {
2215       assert(is_critical_native, "should only be required for critical natives");
2216       // Read from the temporary location
2217       assert(temploc != -1, "must be valid");
2218       i = temploc;
2219       temploc = -1;
2220     }
2221 #ifdef ASSERT
2222     if (in_regs[i].first()->is_Register()) {
2223       assert(!reg_destroyed[in_regs[i].first()->as_Register()->encoding()], "destroyed reg!");
2224     } else if (in_regs[i].first()->is_XMMRegister()) {
2225       assert(!freg_destroyed[in_regs[i].first()->as_XMMRegister()->encoding()], "destroyed reg!");
2226     }
2227     if (out_regs[c_arg].first()->is_Register()) {
2228       reg_destroyed[out_regs[c_arg].first()->as_Register()->encoding()] = true;
2229     } else if (out_regs[c_arg].first()->is_XMMRegister()) {
2230       freg_destroyed[out_regs[c_arg].first()->as_XMMRegister()->encoding()] = true;
2231     }
2232 #endif /* ASSERT */
2233     switch (in_sig_bt[i]) {
2234       case T_ARRAY:
2235         if (is_critical_native) {
2236           unpack_array_argument(masm, in_regs[i], in_elem_bt[i], out_regs[c_arg + 1], out_regs[c_arg]);
2237           c_arg++;
2238 #ifdef ASSERT
2239           if (out_regs[c_arg].first()->is_Register()) {
2240             reg_destroyed[out_regs[c_arg].first()->as_Register()->encoding()] = true;
2241           } else if (out_regs[c_arg].first()->is_XMMRegister()) {
2242             freg_destroyed[out_regs[c_arg].first()->as_XMMRegister()->encoding()] = true;
2243           }
2244 #endif
2245           break;
2246         }
2247       case T_OBJECT:
2248         assert(!is_critical_native, "no oop arguments");
2249         object_move(masm, map, oop_handle_offset, stack_slots, in_regs[i], out_regs[c_arg],
2250                     ((i == 0) && (!is_static)),
2251                     &receiver_offset);
2252         break;
2253       case T_VOID:
2254         break;
2255 
2256       case T_FLOAT:
2257         float_move(masm, in_regs[i], out_regs[c_arg]);
2258           break;
2259 
2260       case T_DOUBLE:
2261         assert( i + 1 < total_in_args &&
2262                 in_sig_bt[i + 1] == T_VOID &&
2263                 out_sig_bt[c_arg+1] == T_VOID, "bad arg list");
2264         double_move(masm, in_regs[i], out_regs[c_arg]);
2265         break;
2266 
2267       case T_LONG :
2268         long_move(masm, in_regs[i], out_regs[c_arg]);
2269         break;
2270 
2271       case T_ADDRESS: assert(false, "found T_ADDRESS in java args");
2272 
2273       default:
2274         move32_64(masm, in_regs[i], out_regs[c_arg]);
2275     }
2276   }
2277 
2278   int c_arg;
2279 
2280   // Pre-load a static method's oop into r14.  Used both by locking code and
2281   // the normal JNI call code.
2282   if (!is_critical_native) {
2283     // point c_arg at the first arg that is already loaded in case we
2284     // need to spill before we call out
2285     c_arg = total_c_args - total_in_args;
2286 
2287     if (method->is_static()) {
2288 
2289       //  load oop into a register
2290       __ movoop(oop_handle_reg, JNIHandles::make_local(method->method_holder()->java_mirror()));
2291 
2292       // Now handlize the static class mirror it's known not-null.
2293       __ movptr(Address(rsp, klass_offset), oop_handle_reg);
2294       map->set_oop(VMRegImpl::stack2reg(klass_slot_offset));
2295 
2296       // Now get the handle
2297       __ lea(oop_handle_reg, Address(rsp, klass_offset));
2298       // store the klass handle as second argument
2299       __ movptr(c_rarg1, oop_handle_reg);
2300       // and protect the arg if we must spill
2301       c_arg--;
2302     }
2303   } else {
2304     // For JNI critical methods we need to save all registers in save_args.
2305     c_arg = 0;
2306   }
2307 
2308   // Change state to native (we save the return address in the thread, since it might not
2309   // be pushed on the stack when we do a a stack traversal). It is enough that the pc()
2310   // points into the right code segment. It does not have to be the correct return pc.
2311   // We use the same pc/oopMap repeatedly when we call out
2312 
2313   intptr_t the_pc = (intptr_t) __ pc();
2314   oop_maps->add_gc_map(the_pc - start, map);
2315 
2316   __ set_last_Java_frame(rsp, noreg, (address)the_pc);
2317 
2318 
2319   // We have all of the arguments setup at this point. We must not touch any register
2320   // argument registers at this point (what if we save/restore them there are no oop?
2321 
2322   {
2323     SkipIfEqual skip(masm, &DTraceMethodProbes, false);
2324     // protect the args we've loaded
2325     save_args(masm, total_c_args, c_arg, out_regs);
2326     __ mov_metadata(c_rarg1, method());
2327     __ call_VM_leaf(
2328       CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_entry),
2329       r15_thread, c_rarg1);
2330     restore_args(masm, total_c_args, c_arg, out_regs);
2331   }
2332 
2333   // RedefineClasses() tracing support for obsolete method entry
2334   if (log_is_enabled(Trace, redefine, class, obsolete)) {
2335     // protect the args we've loaded
2336     save_args(masm, total_c_args, c_arg, out_regs);
2337     __ mov_metadata(c_rarg1, method());
2338     __ call_VM_leaf(
2339       CAST_FROM_FN_PTR(address, SharedRuntime::rc_trace_method_entry),
2340       r15_thread, c_rarg1);
2341     restore_args(masm, total_c_args, c_arg, out_regs);
2342   }
2343 
2344   // Lock a synchronized method
2345 
2346   // Register definitions used by locking and unlocking
2347 
2348   const Register swap_reg = rax;  // Must use rax for cmpxchg instruction
2349   const Register obj_reg  = rbx;  // Will contain the oop
2350   const Register lock_reg = r13;  // Address of compiler lock object (BasicLock)
2351   const Register old_hdr  = r13;  // value of old header at unlock time
2352 
2353   Label slow_path_lock;
2354   Label lock_done;
2355 
2356   if (method->is_synchronized()) {
2357     assert(!is_critical_native, "unhandled");
2358 
2359 
2360     const int mark_word_offset = BasicLock::displaced_header_offset_in_bytes();
2361 
2362     // Get the handle (the 2nd argument)
2363     __ mov(oop_handle_reg, c_rarg1);
2364 
2365     // Get address of the box
2366 
2367     __ lea(lock_reg, Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size));
2368 
2369     // Load the oop from the handle
2370     __ movptr(obj_reg, Address(oop_handle_reg, 0));
2371 
2372     __ resolve_for_write(OOP_NOT_NULL, obj_reg);
2373     if (UseBiasedLocking) {
2374       __ biased_locking_enter(lock_reg, obj_reg, swap_reg, rscratch1, false, lock_done, &slow_path_lock);
2375     }
2376 
2377     // Load immediate 1 into swap_reg %rax
2378     __ movl(swap_reg, 1);
2379 
2380     // Load (object->mark() | 1) into swap_reg %rax
2381     __ orptr(swap_reg, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
2382 
2383     // Save (object->mark() | 1) into BasicLock's displaced header
2384     __ movptr(Address(lock_reg, mark_word_offset), swap_reg);
2385 
2386     if (os::is_MP()) {
2387       __ lock();
2388     }
2389 
2390     // src -> dest iff dest == rax else rax <- dest
2391     __ cmpxchgptr(lock_reg, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
2392     __ jcc(Assembler::equal, lock_done);
2393 
2394     // Hmm should this move to the slow path code area???
2395 
2396     // Test if the oopMark is an obvious stack pointer, i.e.,
2397     //  1) (mark & 3) == 0, and
2398     //  2) rsp <= mark < mark + os::pagesize()
2399     // These 3 tests can be done by evaluating the following
2400     // expression: ((mark - rsp) & (3 - os::vm_page_size())),
2401     // assuming both stack pointer and pagesize have their
2402     // least significant 2 bits clear.
2403     // NOTE: the oopMark is in swap_reg %rax as the result of cmpxchg
2404 
2405     __ subptr(swap_reg, rsp);
2406     __ andptr(swap_reg, 3 - os::vm_page_size());
2407 
2408     // Save the test result, for recursive case, the result is zero
2409     __ movptr(Address(lock_reg, mark_word_offset), swap_reg);
2410     __ jcc(Assembler::notEqual, slow_path_lock);
2411 
2412     // Slow path will re-enter here
2413 
2414     __ bind(lock_done);
2415   }
2416 
2417 
2418   // Finally just about ready to make the JNI call
2419 
2420 
2421   // get JNIEnv* which is first argument to native
2422   if (!is_critical_native) {
2423     __ lea(c_rarg0, Address(r15_thread, in_bytes(JavaThread::jni_environment_offset())));
2424   }
2425 
2426   // Now set thread in native
2427   __ movl(Address(r15_thread, JavaThread::thread_state_offset()), _thread_in_native);
2428 
2429   __ call(RuntimeAddress(native_func));
2430 
2431   // Verify or restore cpu control state after JNI call
2432   __ restore_cpu_control_state_after_jni();
2433 
2434   // Unpack native results.
2435   switch (ret_type) {
2436   case T_BOOLEAN: __ c2bool(rax);            break;
2437   case T_CHAR   : __ movzwl(rax, rax);      break;
2438   case T_BYTE   : __ sign_extend_byte (rax); break;
2439   case T_SHORT  : __ sign_extend_short(rax); break;
2440   case T_INT    : /* nothing to do */        break;
2441   case T_DOUBLE :
2442   case T_FLOAT  :
2443     // Result is in xmm0 we'll save as needed
2444     break;
2445   case T_ARRAY:                 // Really a handle
2446   case T_OBJECT:                // Really a handle
2447       break; // can't de-handlize until after safepoint check
2448   case T_VOID: break;
2449   case T_LONG: break;
2450   default       : ShouldNotReachHere();
2451   }
2452 
2453   // Switch thread to "native transition" state before reading the synchronization state.
2454   // This additional state is necessary because reading and testing the synchronization
2455   // state is not atomic w.r.t. GC, as this scenario demonstrates:
2456   //     Java thread A, in _thread_in_native state, loads _not_synchronized and is preempted.
2457   //     VM thread changes sync state to synchronizing and suspends threads for GC.
2458   //     Thread A is resumed to finish this native method, but doesn't block here since it
2459   //     didn't see any synchronization is progress, and escapes.
2460   __ movl(Address(r15_thread, JavaThread::thread_state_offset()), _thread_in_native_trans);
2461 
2462   if(os::is_MP()) {
2463     if (UseMembar) {
2464       // Force this write out before the read below
2465       __ membar(Assembler::Membar_mask_bits(
2466            Assembler::LoadLoad | Assembler::LoadStore |
2467            Assembler::StoreLoad | Assembler::StoreStore));
2468     } else {
2469       // Write serialization page so VM thread can do a pseudo remote membar.
2470       // We use the current thread pointer to calculate a thread specific
2471       // offset to write to within the page. This minimizes bus traffic
2472       // due to cache line collision.
2473       __ serialize_memory(r15_thread, rcx);
2474     }
2475   }
2476 
2477   Label after_transition;
2478 
2479   // check for safepoint operation in progress and/or pending suspend requests
2480   {
2481     Label Continue;
2482     Label slow_path;
2483 
2484     __ safepoint_poll(slow_path, r15_thread, rscratch1);
2485 
2486     __ cmpl(Address(r15_thread, JavaThread::suspend_flags_offset()), 0);
2487     __ jcc(Assembler::equal, Continue);
2488     __ bind(slow_path);
2489 
2490     // Don't use call_VM as it will see a possible pending exception and forward it
2491     // and never return here preventing us from clearing _last_native_pc down below.
2492     // Also can't use call_VM_leaf either as it will check to see if rsi & rdi are
2493     // preserved and correspond to the bcp/locals pointers. So we do a runtime call
2494     // by hand.
2495     //
2496     __ vzeroupper();
2497     save_native_result(masm, ret_type, stack_slots);
2498     __ mov(c_rarg0, r15_thread);
2499     __ mov(r12, rsp); // remember sp
2500     __ subptr(rsp, frame::arg_reg_save_area_bytes); // windows
2501     __ andptr(rsp, -16); // align stack as required by ABI
2502     if (!is_critical_native) {
2503       __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans)));
2504     } else {
2505       __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans_and_transition)));
2506     }
2507     __ mov(rsp, r12); // restore sp
2508     __ reinit_heapbase();
2509     // Restore any method result value
2510     restore_native_result(masm, ret_type, stack_slots);
2511 
2512     if (is_critical_native) {
2513       // The call above performed the transition to thread_in_Java so
2514       // skip the transition logic below.
2515       __ jmpb(after_transition);
2516     }
2517 
2518     __ bind(Continue);
2519   }
2520 
2521   // change thread state
2522   __ movl(Address(r15_thread, JavaThread::thread_state_offset()), _thread_in_Java);
2523   __ bind(after_transition);
2524 
2525   Label reguard;
2526   Label reguard_done;
2527   __ cmpl(Address(r15_thread, JavaThread::stack_guard_state_offset()), JavaThread::stack_guard_yellow_reserved_disabled);
2528   __ jcc(Assembler::equal, reguard);
2529   __ bind(reguard_done);
2530 
2531   // native result if any is live
2532 
2533   // Unlock
2534   Label unlock_done;
2535   Label slow_path_unlock;
2536   if (method->is_synchronized()) {
2537 
2538     // Get locked oop from the handle we passed to jni
2539     __ movptr(obj_reg, Address(oop_handle_reg, 0));
2540     __ resolve_for_write(OOP_NOT_NULL, obj_reg);
2541 
2542     Label done;
2543 
2544     if (UseBiasedLocking) {
2545       __ biased_locking_exit(obj_reg, old_hdr, done);
2546     }
2547 
2548     // Simple recursive lock?
2549 
2550     __ cmpptr(Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size), (int32_t)NULL_WORD);
2551     __ jcc(Assembler::equal, done);
2552 
2553     // Must save rax if if it is live now because cmpxchg must use it
2554     if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
2555       save_native_result(masm, ret_type, stack_slots);
2556     }
2557 
2558 
2559     // get address of the stack lock
2560     __ lea(rax, Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size));
2561     //  get old displaced header
2562     __ movptr(old_hdr, Address(rax, 0));
2563 
2564     // Atomic swap old header if oop still contains the stack lock
2565     if (os::is_MP()) {
2566       __ lock();
2567     }
2568     __ cmpxchgptr(old_hdr, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
2569     __ jcc(Assembler::notEqual, slow_path_unlock);
2570 
2571     // slow path re-enters here
2572     __ bind(unlock_done);
2573     if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
2574       restore_native_result(masm, ret_type, stack_slots);
2575     }
2576 
2577     __ bind(done);
2578 
2579   }
2580   {
2581     SkipIfEqual skip(masm, &DTraceMethodProbes, false);
2582     save_native_result(masm, ret_type, stack_slots);
2583     __ mov_metadata(c_rarg1, method());
2584     __ call_VM_leaf(
2585          CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_exit),
2586          r15_thread, c_rarg1);
2587     restore_native_result(masm, ret_type, stack_slots);
2588   }
2589 
2590   __ reset_last_Java_frame(false);
2591 
2592   // Unbox oop result, e.g. JNIHandles::resolve value.
2593   if (ret_type == T_OBJECT || ret_type == T_ARRAY) {
2594     __ resolve_jobject(rax /* value */,
2595                        r15_thread /* thread */,
2596                        rcx /* tmp */);
2597   }
2598 
2599   if (CheckJNICalls) {
2600     // clear_pending_jni_exception_check
2601     __ movptr(Address(r15_thread, JavaThread::pending_jni_exception_check_fn_offset()), NULL_WORD);
2602   }
2603 
2604   if (!is_critical_native) {
2605     // reset handle block
2606     __ movptr(rcx, Address(r15_thread, JavaThread::active_handles_offset()));
2607     __ movl(Address(rcx, JNIHandleBlock::top_offset_in_bytes()), (int32_t)NULL_WORD);
2608   }
2609 
2610   // pop our frame
2611 
2612   __ leave();
2613 
2614   if (!is_critical_native) {
2615     // Any exception pending?
2616     __ cmpptr(Address(r15_thread, in_bytes(Thread::pending_exception_offset())), (int32_t)NULL_WORD);
2617     __ jcc(Assembler::notEqual, exception_pending);
2618   }
2619 
2620   // Return
2621 
2622   __ ret(0);
2623 
2624   // Unexpected paths are out of line and go here
2625 
2626   if (!is_critical_native) {
2627     // forward the exception
2628     __ bind(exception_pending);
2629 
2630     // and forward the exception
2631     __ jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
2632   }
2633 
2634   // Slow path locking & unlocking
2635   if (method->is_synchronized()) {
2636 
2637     // BEGIN Slow path lock
2638     __ bind(slow_path_lock);
2639 
2640     // has last_Java_frame setup. No exceptions so do vanilla call not call_VM
2641     // args are (oop obj, BasicLock* lock, JavaThread* thread)
2642 
2643     // protect the args we've loaded
2644     save_args(masm, total_c_args, c_arg, out_regs);
2645 
2646     __ mov(c_rarg0, obj_reg);
2647     __ mov(c_rarg1, lock_reg);
2648     __ mov(c_rarg2, r15_thread);
2649 
2650     // Not a leaf but we have last_Java_frame setup as we want
2651     __ call_VM_leaf(CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_locking_C), 3);
2652     restore_args(masm, total_c_args, c_arg, out_regs);
2653 
2654 #ifdef ASSERT
2655     { Label L;
2656     __ cmpptr(Address(r15_thread, in_bytes(Thread::pending_exception_offset())), (int32_t)NULL_WORD);
2657     __ jcc(Assembler::equal, L);
2658     __ stop("no pending exception allowed on exit from monitorenter");
2659     __ bind(L);
2660     }
2661 #endif
2662     __ jmp(lock_done);
2663 
2664     // END Slow path lock
2665 
2666     // BEGIN Slow path unlock
2667     __ bind(slow_path_unlock);
2668 
2669     // If we haven't already saved the native result we must save it now as xmm registers
2670     // are still exposed.
2671     __ vzeroupper();
2672     if (ret_type == T_FLOAT || ret_type == T_DOUBLE ) {
2673       save_native_result(masm, ret_type, stack_slots);
2674     }
2675 
2676     __ lea(c_rarg1, Address(rsp, lock_slot_offset * VMRegImpl::stack_slot_size));
2677 
2678     __ mov(c_rarg0, obj_reg);
2679     __ mov(c_rarg2, r15_thread);
2680     __ mov(r12, rsp); // remember sp
2681     __ subptr(rsp, frame::arg_reg_save_area_bytes); // windows
2682     __ andptr(rsp, -16); // align stack as required by ABI
2683 
2684     // Save pending exception around call to VM (which contains an EXCEPTION_MARK)
2685     // NOTE that obj_reg == rbx currently
2686     __ movptr(rbx, Address(r15_thread, in_bytes(Thread::pending_exception_offset())));
2687     __ movptr(Address(r15_thread, in_bytes(Thread::pending_exception_offset())), (int32_t)NULL_WORD);
2688 
2689     // args are (oop obj, BasicLock* lock, JavaThread* thread)
2690     __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C)));
2691     __ mov(rsp, r12); // restore sp
2692     __ reinit_heapbase();
2693 #ifdef ASSERT
2694     {
2695       Label L;
2696       __ cmpptr(Address(r15_thread, in_bytes(Thread::pending_exception_offset())), (int)NULL_WORD);
2697       __ jcc(Assembler::equal, L);
2698       __ stop("no pending exception allowed on exit complete_monitor_unlocking_C");
2699       __ bind(L);
2700     }
2701 #endif /* ASSERT */
2702 
2703     __ movptr(Address(r15_thread, in_bytes(Thread::pending_exception_offset())), rbx);
2704 
2705     if (ret_type == T_FLOAT || ret_type == T_DOUBLE ) {
2706       restore_native_result(masm, ret_type, stack_slots);
2707     }
2708     __ jmp(unlock_done);
2709 
2710     // END Slow path unlock
2711 
2712   } // synchronized
2713 
2714   // SLOW PATH Reguard the stack if needed
2715 
2716   __ bind(reguard);
2717   __ vzeroupper();
2718   save_native_result(masm, ret_type, stack_slots);
2719   __ mov(r12, rsp); // remember sp
2720   __ subptr(rsp, frame::arg_reg_save_area_bytes); // windows
2721   __ andptr(rsp, -16); // align stack as required by ABI
2722   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::reguard_yellow_pages)));
2723   __ mov(rsp, r12); // restore sp
2724   __ reinit_heapbase();
2725   restore_native_result(masm, ret_type, stack_slots);
2726   // and continue
2727   __ jmp(reguard_done);
2728 
2729 
2730 
2731   __ flush();
2732 
2733   nmethod *nm = nmethod::new_native_nmethod(method,
2734                                             compile_id,
2735                                             masm->code(),
2736                                             vep_offset,
2737                                             frame_complete,
2738                                             stack_slots / VMRegImpl::slots_per_word,
2739                                             (is_static ? in_ByteSize(klass_offset) : in_ByteSize(receiver_offset)),
2740                                             in_ByteSize(lock_slot_offset*VMRegImpl::stack_slot_size),
2741                                             oop_maps);
2742 
2743   if (is_critical_native) {
2744     nm->set_lazy_critical_native(true);
2745   }
2746 
2747   return nm;
2748 
2749 }
2750 
2751 // this function returns the adjust size (in number of words) to a c2i adapter
2752 // activation for use during deoptimization
2753 int Deoptimization::last_frame_adjust(int callee_parameters, int callee_locals ) {
2754   return (callee_locals - callee_parameters) * Interpreter::stackElementWords;
2755 }
2756 
2757 
2758 uint SharedRuntime::out_preserve_stack_slots() {
2759   return 0;
2760 }
2761 
2762 //------------------------------generate_deopt_blob----------------------------
2763 void SharedRuntime::generate_deopt_blob() {
2764   // Allocate space for the code
2765   ResourceMark rm;
2766   // Setup code generation tools
2767   int pad = 0;
2768 #if INCLUDE_JVMCI
2769   if (EnableJVMCI || UseAOT) {
2770     pad += 512; // Increase the buffer size when compiling for JVMCI
2771   }
2772 #endif
2773   CodeBuffer buffer("deopt_blob", 2048+pad, 1024);
2774   MacroAssembler* masm = new MacroAssembler(&buffer);
2775   int frame_size_in_words;
2776   OopMap* map = NULL;
2777   OopMapSet *oop_maps = new OopMapSet();
2778 
2779   // -------------
2780   // This code enters when returning to a de-optimized nmethod.  A return
2781   // address has been pushed on the the stack, and return values are in
2782   // registers.
2783   // If we are doing a normal deopt then we were called from the patched
2784   // nmethod from the point we returned to the nmethod. So the return
2785   // address on the stack is wrong by NativeCall::instruction_size
2786   // We will adjust the value so it looks like we have the original return
2787   // address on the stack (like when we eagerly deoptimized).
2788   // In the case of an exception pending when deoptimizing, we enter
2789   // with a return address on the stack that points after the call we patched
2790   // into the exception handler. We have the following register state from,
2791   // e.g., the forward exception stub (see stubGenerator_x86_64.cpp).
2792   //    rax: exception oop
2793   //    rbx: exception handler
2794   //    rdx: throwing pc
2795   // So in this case we simply jam rdx into the useless return address and
2796   // the stack looks just like we want.
2797   //
2798   // At this point we need to de-opt.  We save the argument return
2799   // registers.  We call the first C routine, fetch_unroll_info().  This
2800   // routine captures the return values and returns a structure which
2801   // describes the current frame size and the sizes of all replacement frames.
2802   // The current frame is compiled code and may contain many inlined
2803   // functions, each with their own JVM state.  We pop the current frame, then
2804   // push all the new frames.  Then we call the C routine unpack_frames() to
2805   // populate these frames.  Finally unpack_frames() returns us the new target
2806   // address.  Notice that callee-save registers are BLOWN here; they have
2807   // already been captured in the vframeArray at the time the return PC was
2808   // patched.
2809   address start = __ pc();
2810   Label cont;
2811 
2812   // Prolog for non exception case!
2813 
2814   // Save everything in sight.
2815   map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
2816 
2817   // Normal deoptimization.  Save exec mode for unpack_frames.
2818   __ movl(r14, Deoptimization::Unpack_deopt); // callee-saved
2819   __ jmp(cont);
2820 
2821   int reexecute_offset = __ pc() - start;
2822 #if INCLUDE_JVMCI && !defined(COMPILER1)
2823   if (EnableJVMCI && UseJVMCICompiler) {
2824     // JVMCI does not use this kind of deoptimization
2825     __ should_not_reach_here();
2826   }
2827 #endif
2828 
2829   // Reexecute case
2830   // return address is the pc describes what bci to do re-execute at
2831 
2832   // No need to update map as each call to save_live_registers will produce identical oopmap
2833   (void) RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
2834 
2835   __ movl(r14, Deoptimization::Unpack_reexecute); // callee-saved
2836   __ jmp(cont);
2837 
2838 #if INCLUDE_JVMCI
2839   Label after_fetch_unroll_info_call;
2840   int implicit_exception_uncommon_trap_offset = 0;
2841   int uncommon_trap_offset = 0;
2842 
2843   if (EnableJVMCI || UseAOT) {
2844     implicit_exception_uncommon_trap_offset = __ pc() - start;
2845 
2846     __ pushptr(Address(r15_thread, in_bytes(JavaThread::jvmci_implicit_exception_pc_offset())));
2847     __ movptr(Address(r15_thread, in_bytes(JavaThread::jvmci_implicit_exception_pc_offset())), (int32_t)NULL_WORD);
2848 
2849     uncommon_trap_offset = __ pc() - start;
2850 
2851     // Save everything in sight.
2852     RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
2853     // fetch_unroll_info needs to call last_java_frame()
2854     __ set_last_Java_frame(noreg, noreg, NULL);
2855 
2856     __ movl(c_rarg1, Address(r15_thread, in_bytes(JavaThread::pending_deoptimization_offset())));
2857     __ movl(Address(r15_thread, in_bytes(JavaThread::pending_deoptimization_offset())), -1);
2858 
2859     __ movl(r14, (int32_t)Deoptimization::Unpack_reexecute);
2860     __ mov(c_rarg0, r15_thread);
2861     __ movl(c_rarg2, r14); // exec mode
2862     __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::uncommon_trap)));
2863     oop_maps->add_gc_map( __ pc()-start, map->deep_copy());
2864 
2865     __ reset_last_Java_frame(false);
2866 
2867     __ jmp(after_fetch_unroll_info_call);
2868   } // EnableJVMCI
2869 #endif // INCLUDE_JVMCI
2870 
2871   int exception_offset = __ pc() - start;
2872 
2873   // Prolog for exception case
2874 
2875   // all registers are dead at this entry point, except for rax, and
2876   // rdx which contain the exception oop and exception pc
2877   // respectively.  Set them in TLS and fall thru to the
2878   // unpack_with_exception_in_tls entry point.
2879 
2880   __ movptr(Address(r15_thread, JavaThread::exception_pc_offset()), rdx);
2881   __ movptr(Address(r15_thread, JavaThread::exception_oop_offset()), rax);
2882 
2883   int exception_in_tls_offset = __ pc() - start;
2884 
2885   // new implementation because exception oop is now passed in JavaThread
2886 
2887   // Prolog for exception case
2888   // All registers must be preserved because they might be used by LinearScan
2889   // Exceptiop oop and throwing PC are passed in JavaThread
2890   // tos: stack at point of call to method that threw the exception (i.e. only
2891   // args are on the stack, no return address)
2892 
2893   // make room on stack for the return address
2894   // It will be patched later with the throwing pc. The correct value is not
2895   // available now because loading it from memory would destroy registers.
2896   __ push(0);
2897 
2898   // Save everything in sight.
2899   map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
2900 
2901   // Now it is safe to overwrite any register
2902 
2903   // Deopt during an exception.  Save exec mode for unpack_frames.
2904   __ movl(r14, Deoptimization::Unpack_exception); // callee-saved
2905 
2906   // load throwing pc from JavaThread and patch it as the return address
2907   // of the current frame. Then clear the field in JavaThread
2908 
2909   __ movptr(rdx, Address(r15_thread, JavaThread::exception_pc_offset()));
2910   __ movptr(Address(rbp, wordSize), rdx);
2911   __ movptr(Address(r15_thread, JavaThread::exception_pc_offset()), (int32_t)NULL_WORD);
2912 
2913 #ifdef ASSERT
2914   // verify that there is really an exception oop in JavaThread
2915   __ movptr(rax, Address(r15_thread, JavaThread::exception_oop_offset()));
2916   __ verify_oop(rax);
2917 
2918   // verify that there is no pending exception
2919   Label no_pending_exception;
2920   __ movptr(rax, Address(r15_thread, Thread::pending_exception_offset()));
2921   __ testptr(rax, rax);
2922   __ jcc(Assembler::zero, no_pending_exception);
2923   __ stop("must not have pending exception here");
2924   __ bind(no_pending_exception);
2925 #endif
2926 
2927   __ bind(cont);
2928 
2929   // Call C code.  Need thread and this frame, but NOT official VM entry
2930   // crud.  We cannot block on this call, no GC can happen.
2931   //
2932   // UnrollBlock* fetch_unroll_info(JavaThread* thread)
2933 
2934   // fetch_unroll_info needs to call last_java_frame().
2935 
2936   __ set_last_Java_frame(noreg, noreg, NULL);
2937 #ifdef ASSERT
2938   { Label L;
2939     __ cmpptr(Address(r15_thread,
2940                     JavaThread::last_Java_fp_offset()),
2941             (int32_t)0);
2942     __ jcc(Assembler::equal, L);
2943     __ stop("SharedRuntime::generate_deopt_blob: last_Java_fp not cleared");
2944     __ bind(L);
2945   }
2946 #endif // ASSERT
2947   __ mov(c_rarg0, r15_thread);
2948   __ movl(c_rarg1, r14); // exec_mode
2949   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::fetch_unroll_info)));
2950 
2951   // Need to have an oopmap that tells fetch_unroll_info where to
2952   // find any register it might need.
2953   oop_maps->add_gc_map(__ pc() - start, map);
2954 
2955   __ reset_last_Java_frame(false);
2956 
2957 #if INCLUDE_JVMCI
2958   if (EnableJVMCI || UseAOT) {
2959     __ bind(after_fetch_unroll_info_call);
2960   }
2961 #endif
2962 
2963   // Load UnrollBlock* into rdi
2964   __ mov(rdi, rax);
2965 
2966   __ movl(r14, Address(rdi, Deoptimization::UnrollBlock::unpack_kind_offset_in_bytes()));
2967    Label noException;
2968   __ cmpl(r14, Deoptimization::Unpack_exception);   // Was exception pending?
2969   __ jcc(Assembler::notEqual, noException);
2970   __ movptr(rax, Address(r15_thread, JavaThread::exception_oop_offset()));
2971   // QQQ this is useless it was NULL above
2972   __ movptr(rdx, Address(r15_thread, JavaThread::exception_pc_offset()));
2973   __ movptr(Address(r15_thread, JavaThread::exception_oop_offset()), (int32_t)NULL_WORD);
2974   __ movptr(Address(r15_thread, JavaThread::exception_pc_offset()), (int32_t)NULL_WORD);
2975 
2976   __ verify_oop(rax);
2977 
2978   // Overwrite the result registers with the exception results.
2979   __ movptr(Address(rsp, RegisterSaver::rax_offset_in_bytes()), rax);
2980   // I think this is useless
2981   __ movptr(Address(rsp, RegisterSaver::rdx_offset_in_bytes()), rdx);
2982 
2983   __ bind(noException);
2984 
2985   // Only register save data is on the stack.
2986   // Now restore the result registers.  Everything else is either dead
2987   // or captured in the vframeArray.
2988   RegisterSaver::restore_result_registers(masm);
2989 
2990   // All of the register save area has been popped of the stack. Only the
2991   // return address remains.
2992 
2993   // Pop all the frames we must move/replace.
2994   //
2995   // Frame picture (youngest to oldest)
2996   // 1: self-frame (no frame link)
2997   // 2: deopting frame  (no frame link)
2998   // 3: caller of deopting frame (could be compiled/interpreted).
2999   //
3000   // Note: by leaving the return address of self-frame on the stack
3001   // and using the size of frame 2 to adjust the stack
3002   // when we are done the return to frame 3 will still be on the stack.
3003 
3004   // Pop deoptimized frame
3005   __ movl(rcx, Address(rdi, Deoptimization::UnrollBlock::size_of_deoptimized_frame_offset_in_bytes()));
3006   __ addptr(rsp, rcx);
3007 
3008   // rsp should be pointing at the return address to the caller (3)
3009 
3010   // Pick up the initial fp we should save
3011   // restore rbp before stack bang because if stack overflow is thrown it needs to be pushed (and preserved)
3012   __ movptr(rbp, Address(rdi, Deoptimization::UnrollBlock::initial_info_offset_in_bytes()));
3013 
3014 #ifdef ASSERT
3015   // Compilers generate code that bang the stack by as much as the
3016   // interpreter would need. So this stack banging should never
3017   // trigger a fault. Verify that it does not on non product builds.
3018   if (UseStackBanging) {
3019     __ movl(rbx, Address(rdi, Deoptimization::UnrollBlock::total_frame_sizes_offset_in_bytes()));
3020     __ bang_stack_size(rbx, rcx);
3021   }
3022 #endif
3023 
3024   // Load address of array of frame pcs into rcx
3025   __ movptr(rcx, Address(rdi, Deoptimization::UnrollBlock::frame_pcs_offset_in_bytes()));
3026 
3027   // Trash the old pc
3028   __ addptr(rsp, wordSize);
3029 
3030   // Load address of array of frame sizes into rsi
3031   __ movptr(rsi, Address(rdi, Deoptimization::UnrollBlock::frame_sizes_offset_in_bytes()));
3032 
3033   // Load counter into rdx
3034   __ movl(rdx, Address(rdi, Deoptimization::UnrollBlock::number_of_frames_offset_in_bytes()));
3035 
3036   // Now adjust the caller's stack to make up for the extra locals
3037   // but record the original sp so that we can save it in the skeletal interpreter
3038   // frame and the stack walking of interpreter_sender will get the unextended sp
3039   // value and not the "real" sp value.
3040 
3041   const Register sender_sp = r8;
3042 
3043   __ mov(sender_sp, rsp);
3044   __ movl(rbx, Address(rdi,
3045                        Deoptimization::UnrollBlock::
3046                        caller_adjustment_offset_in_bytes()));
3047   __ subptr(rsp, rbx);
3048 
3049   // Push interpreter frames in a loop
3050   Label loop;
3051   __ bind(loop);
3052   __ movptr(rbx, Address(rsi, 0));      // Load frame size
3053   __ subptr(rbx, 2*wordSize);           // We'll push pc and ebp by hand
3054   __ pushptr(Address(rcx, 0));          // Save return address
3055   __ enter();                           // Save old & set new ebp
3056   __ subptr(rsp, rbx);                  // Prolog
3057   // This value is corrected by layout_activation_impl
3058   __ movptr(Address(rbp, frame::interpreter_frame_last_sp_offset * wordSize), (int32_t)NULL_WORD );
3059   __ movptr(Address(rbp, frame::interpreter_frame_sender_sp_offset * wordSize), sender_sp); // Make it walkable
3060   __ mov(sender_sp, rsp);               // Pass sender_sp to next frame
3061   __ addptr(rsi, wordSize);             // Bump array pointer (sizes)
3062   __ addptr(rcx, wordSize);             // Bump array pointer (pcs)
3063   __ decrementl(rdx);                   // Decrement counter
3064   __ jcc(Assembler::notZero, loop);
3065   __ pushptr(Address(rcx, 0));          // Save final return address
3066 
3067   // Re-push self-frame
3068   __ enter();                           // Save old & set new ebp
3069 
3070   // Allocate a full sized register save area.
3071   // Return address and rbp are in place, so we allocate two less words.
3072   __ subptr(rsp, (frame_size_in_words - 2) * wordSize);
3073 
3074   // Restore frame locals after moving the frame
3075   __ movdbl(Address(rsp, RegisterSaver::xmm0_offset_in_bytes()), xmm0);
3076   __ movptr(Address(rsp, RegisterSaver::rax_offset_in_bytes()), rax);
3077 
3078   // Call C code.  Need thread but NOT official VM entry
3079   // crud.  We cannot block on this call, no GC can happen.  Call should
3080   // restore return values to their stack-slots with the new SP.
3081   //
3082   // void Deoptimization::unpack_frames(JavaThread* thread, int exec_mode)
3083 
3084   // Use rbp because the frames look interpreted now
3085   // Save "the_pc" since it cannot easily be retrieved using the last_java_SP after we aligned SP.
3086   // Don't need the precise return PC here, just precise enough to point into this code blob.
3087   address the_pc = __ pc();
3088   __ set_last_Java_frame(noreg, rbp, the_pc);
3089 
3090   __ andptr(rsp, -(StackAlignmentInBytes));  // Fix stack alignment as required by ABI
3091   __ mov(c_rarg0, r15_thread);
3092   __ movl(c_rarg1, r14); // second arg: exec_mode
3093   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::unpack_frames)));
3094   // Revert SP alignment after call since we're going to do some SP relative addressing below
3095   __ movptr(rsp, Address(r15_thread, JavaThread::last_Java_sp_offset()));
3096 
3097   // Set an oopmap for the call site
3098   // Use the same PC we used for the last java frame
3099   oop_maps->add_gc_map(the_pc - start,
3100                        new OopMap( frame_size_in_words, 0 ));
3101 
3102   // Clear fp AND pc
3103   __ reset_last_Java_frame(true);
3104 
3105   // Collect return values
3106   __ movdbl(xmm0, Address(rsp, RegisterSaver::xmm0_offset_in_bytes()));
3107   __ movptr(rax, Address(rsp, RegisterSaver::rax_offset_in_bytes()));
3108   // I think this is useless (throwing pc?)
3109   __ movptr(rdx, Address(rsp, RegisterSaver::rdx_offset_in_bytes()));
3110 
3111   // Pop self-frame.
3112   __ leave();                           // Epilog
3113 
3114   // Jump to interpreter
3115   __ ret(0);
3116 
3117   // Make sure all code is generated
3118   masm->flush();
3119 
3120   _deopt_blob = DeoptimizationBlob::create(&buffer, oop_maps, 0, exception_offset, reexecute_offset, frame_size_in_words);
3121   _deopt_blob->set_unpack_with_exception_in_tls_offset(exception_in_tls_offset);
3122 #if INCLUDE_JVMCI
3123   if (EnableJVMCI || UseAOT) {
3124     _deopt_blob->set_uncommon_trap_offset(uncommon_trap_offset);
3125     _deopt_blob->set_implicit_exception_uncommon_trap_offset(implicit_exception_uncommon_trap_offset);
3126   }
3127 #endif
3128 }
3129 
3130 #ifdef COMPILER2
3131 //------------------------------generate_uncommon_trap_blob--------------------
3132 void SharedRuntime::generate_uncommon_trap_blob() {
3133   // Allocate space for the code
3134   ResourceMark rm;
3135   // Setup code generation tools
3136   CodeBuffer buffer("uncommon_trap_blob", 2048, 1024);
3137   MacroAssembler* masm = new MacroAssembler(&buffer);
3138 
3139   assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
3140 
3141   address start = __ pc();
3142 
3143   if (UseRTMLocking) {
3144     // Abort RTM transaction before possible nmethod deoptimization.
3145     __ xabort(0);
3146   }
3147 
3148   // Push self-frame.  We get here with a return address on the
3149   // stack, so rsp is 8-byte aligned until we allocate our frame.
3150   __ subptr(rsp, SimpleRuntimeFrame::return_off << LogBytesPerInt); // Epilog!
3151 
3152   // No callee saved registers. rbp is assumed implicitly saved
3153   __ movptr(Address(rsp, SimpleRuntimeFrame::rbp_off << LogBytesPerInt), rbp);
3154 
3155   // compiler left unloaded_class_index in j_rarg0 move to where the
3156   // runtime expects it.
3157   __ movl(c_rarg1, j_rarg0);
3158 
3159   __ set_last_Java_frame(noreg, noreg, NULL);
3160 
3161   // Call C code.  Need thread but NOT official VM entry
3162   // crud.  We cannot block on this call, no GC can happen.  Call should
3163   // capture callee-saved registers as well as return values.
3164   // Thread is in rdi already.
3165   //
3166   // UnrollBlock* uncommon_trap(JavaThread* thread, jint unloaded_class_index);
3167 
3168   __ mov(c_rarg0, r15_thread);
3169   __ movl(c_rarg2, Deoptimization::Unpack_uncommon_trap);
3170   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::uncommon_trap)));
3171 
3172   // Set an oopmap for the call site
3173   OopMapSet* oop_maps = new OopMapSet();
3174   OopMap* map = new OopMap(SimpleRuntimeFrame::framesize, 0);
3175 
3176   // location of rbp is known implicitly by the frame sender code
3177 
3178   oop_maps->add_gc_map(__ pc() - start, map);
3179 
3180   __ reset_last_Java_frame(false);
3181 
3182   // Load UnrollBlock* into rdi
3183   __ mov(rdi, rax);
3184 
3185 #ifdef ASSERT
3186   { Label L;
3187     __ cmpptr(Address(rdi, Deoptimization::UnrollBlock::unpack_kind_offset_in_bytes()),
3188             (int32_t)Deoptimization::Unpack_uncommon_trap);
3189     __ jcc(Assembler::equal, L);
3190     __ stop("SharedRuntime::generate_deopt_blob: expected Unpack_uncommon_trap");
3191     __ bind(L);
3192   }
3193 #endif
3194 
3195   // Pop all the frames we must move/replace.
3196   //
3197   // Frame picture (youngest to oldest)
3198   // 1: self-frame (no frame link)
3199   // 2: deopting frame  (no frame link)
3200   // 3: caller of deopting frame (could be compiled/interpreted).
3201 
3202   // Pop self-frame.  We have no frame, and must rely only on rax and rsp.
3203   __ addptr(rsp, (SimpleRuntimeFrame::framesize - 2) << LogBytesPerInt); // Epilog!
3204 
3205   // Pop deoptimized frame (int)
3206   __ movl(rcx, Address(rdi,
3207                        Deoptimization::UnrollBlock::
3208                        size_of_deoptimized_frame_offset_in_bytes()));
3209   __ addptr(rsp, rcx);
3210 
3211   // rsp should be pointing at the return address to the caller (3)
3212 
3213   // Pick up the initial fp we should save
3214   // restore rbp before stack bang because if stack overflow is thrown it needs to be pushed (and preserved)
3215   __ movptr(rbp, Address(rdi, Deoptimization::UnrollBlock::initial_info_offset_in_bytes()));
3216 
3217 #ifdef ASSERT
3218   // Compilers generate code that bang the stack by as much as the
3219   // interpreter would need. So this stack banging should never
3220   // trigger a fault. Verify that it does not on non product builds.
3221   if (UseStackBanging) {
3222     __ movl(rbx, Address(rdi ,Deoptimization::UnrollBlock::total_frame_sizes_offset_in_bytes()));
3223     __ bang_stack_size(rbx, rcx);
3224   }
3225 #endif
3226 
3227   // Load address of array of frame pcs into rcx (address*)
3228   __ movptr(rcx, Address(rdi, Deoptimization::UnrollBlock::frame_pcs_offset_in_bytes()));
3229 
3230   // Trash the return pc
3231   __ addptr(rsp, wordSize);
3232 
3233   // Load address of array of frame sizes into rsi (intptr_t*)
3234   __ movptr(rsi, Address(rdi, Deoptimization::UnrollBlock:: frame_sizes_offset_in_bytes()));
3235 
3236   // Counter
3237   __ movl(rdx, Address(rdi, Deoptimization::UnrollBlock:: number_of_frames_offset_in_bytes())); // (int)
3238 
3239   // Now adjust the caller's stack to make up for the extra locals but
3240   // record the original sp so that we can save it in the skeletal
3241   // interpreter frame and the stack walking of interpreter_sender
3242   // will get the unextended sp value and not the "real" sp value.
3243 
3244   const Register sender_sp = r8;
3245 
3246   __ mov(sender_sp, rsp);
3247   __ movl(rbx, Address(rdi, Deoptimization::UnrollBlock:: caller_adjustment_offset_in_bytes())); // (int)
3248   __ subptr(rsp, rbx);
3249 
3250   // Push interpreter frames in a loop
3251   Label loop;
3252   __ bind(loop);
3253   __ movptr(rbx, Address(rsi, 0)); // Load frame size
3254   __ subptr(rbx, 2 * wordSize);    // We'll push pc and rbp by hand
3255   __ pushptr(Address(rcx, 0));     // Save return address
3256   __ enter();                      // Save old & set new rbp
3257   __ subptr(rsp, rbx);             // Prolog
3258   __ movptr(Address(rbp, frame::interpreter_frame_sender_sp_offset * wordSize),
3259             sender_sp);            // Make it walkable
3260   // This value is corrected by layout_activation_impl
3261   __ movptr(Address(rbp, frame::interpreter_frame_last_sp_offset * wordSize), (int32_t)NULL_WORD );
3262   __ mov(sender_sp, rsp);          // Pass sender_sp to next frame
3263   __ addptr(rsi, wordSize);        // Bump array pointer (sizes)
3264   __ addptr(rcx, wordSize);        // Bump array pointer (pcs)
3265   __ decrementl(rdx);              // Decrement counter
3266   __ jcc(Assembler::notZero, loop);
3267   __ pushptr(Address(rcx, 0));     // Save final return address
3268 
3269   // Re-push self-frame
3270   __ enter();                 // Save old & set new rbp
3271   __ subptr(rsp, (SimpleRuntimeFrame::framesize - 4) << LogBytesPerInt);
3272                               // Prolog
3273 
3274   // Use rbp because the frames look interpreted now
3275   // Save "the_pc" since it cannot easily be retrieved using the last_java_SP after we aligned SP.
3276   // Don't need the precise return PC here, just precise enough to point into this code blob.
3277   address the_pc = __ pc();
3278   __ set_last_Java_frame(noreg, rbp, the_pc);
3279 
3280   // Call C code.  Need thread but NOT official VM entry
3281   // crud.  We cannot block on this call, no GC can happen.  Call should
3282   // restore return values to their stack-slots with the new SP.
3283   // Thread is in rdi already.
3284   //
3285   // BasicType unpack_frames(JavaThread* thread, int exec_mode);
3286 
3287   __ andptr(rsp, -(StackAlignmentInBytes)); // Align SP as required by ABI
3288   __ mov(c_rarg0, r15_thread);
3289   __ movl(c_rarg1, Deoptimization::Unpack_uncommon_trap);
3290   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::unpack_frames)));
3291 
3292   // Set an oopmap for the call site
3293   // Use the same PC we used for the last java frame
3294   oop_maps->add_gc_map(the_pc - start, new OopMap(SimpleRuntimeFrame::framesize, 0));
3295 
3296   // Clear fp AND pc
3297   __ reset_last_Java_frame(true);
3298 
3299   // Pop self-frame.
3300   __ leave();                 // Epilog
3301 
3302   // Jump to interpreter
3303   __ ret(0);
3304 
3305   // Make sure all code is generated
3306   masm->flush();
3307 
3308   _uncommon_trap_blob =  UncommonTrapBlob::create(&buffer, oop_maps,
3309                                                  SimpleRuntimeFrame::framesize >> 1);
3310 }
3311 #endif // COMPILER2
3312 
3313 
3314 //------------------------------generate_handler_blob------
3315 //
3316 // Generate a special Compile2Runtime blob that saves all registers,
3317 // and setup oopmap.
3318 //
3319 SafepointBlob* SharedRuntime::generate_handler_blob(address call_ptr, int poll_type) {
3320   assert(StubRoutines::forward_exception_entry() != NULL,
3321          "must be generated before");
3322 
3323   ResourceMark rm;
3324   OopMapSet *oop_maps = new OopMapSet();
3325   OopMap* map;
3326 
3327   // Allocate space for the code.  Setup code generation tools.
3328   CodeBuffer buffer("handler_blob", 2048, 1024);
3329   MacroAssembler* masm = new MacroAssembler(&buffer);
3330 
3331   address start   = __ pc();
3332   address call_pc = NULL;
3333   int frame_size_in_words;
3334   bool cause_return = (poll_type == POLL_AT_RETURN);
3335   bool save_vectors = (poll_type == POLL_AT_VECTOR_LOOP);
3336 
3337   if (UseRTMLocking) {
3338     // Abort RTM transaction before calling runtime
3339     // because critical section will be large and will be
3340     // aborted anyway. Also nmethod could be deoptimized.
3341     __ xabort(0);
3342   }
3343 
3344   // Make room for return address (or push it again)
3345   if (!cause_return) {
3346     __ push(rbx);
3347   }
3348 
3349   // Save registers, fpu state, and flags
3350   map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words, save_vectors);
3351 
3352   // The following is basically a call_VM.  However, we need the precise
3353   // address of the call in order to generate an oopmap. Hence, we do all the
3354   // work outselves.
3355 
3356   __ set_last_Java_frame(noreg, noreg, NULL);
3357 
3358   // The return address must always be correct so that frame constructor never
3359   // sees an invalid pc.
3360 
3361   if (!cause_return) {
3362     // Get the return pc saved by the signal handler and stash it in its appropriate place on the stack.
3363     // Additionally, rbx is a callee saved register and we can look at it later to determine
3364     // if someone changed the return address for us!
3365     __ movptr(rbx, Address(r15_thread, JavaThread::saved_exception_pc_offset()));
3366     __ movptr(Address(rbp, wordSize), rbx);
3367   }
3368 
3369   // Do the call
3370   __ mov(c_rarg0, r15_thread);
3371   __ call(RuntimeAddress(call_ptr));
3372 
3373   // Set an oopmap for the call site.  This oopmap will map all
3374   // oop-registers and debug-info registers as callee-saved.  This
3375   // will allow deoptimization at this safepoint to find all possible
3376   // debug-info recordings, as well as let GC find all oops.
3377 
3378   oop_maps->add_gc_map( __ pc() - start, map);
3379 
3380   Label noException;
3381 
3382   __ reset_last_Java_frame(false);
3383 
3384   __ cmpptr(Address(r15_thread, Thread::pending_exception_offset()), (int32_t)NULL_WORD);
3385   __ jcc(Assembler::equal, noException);
3386 
3387   // Exception pending
3388 
3389   RegisterSaver::restore_live_registers(masm, save_vectors);
3390 
3391   __ jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
3392 
3393   // No exception case
3394   __ bind(noException);
3395 
3396   Label no_adjust, bail, no_prefix, not_special;
3397   if (SafepointMechanism::uses_thread_local_poll() && !cause_return) {
3398     // If our stashed return pc was modified by the runtime we avoid touching it
3399     __ cmpptr(rbx, Address(rbp, wordSize));
3400     __ jccb(Assembler::notEqual, no_adjust);
3401 
3402     // Skip over the poll instruction.
3403     // See NativeInstruction::is_safepoint_poll()
3404     // Possible encodings:
3405     //      85 00       test   %eax,(%rax)
3406     //      85 01       test   %eax,(%rcx)
3407     //      85 02       test   %eax,(%rdx)
3408     //      85 03       test   %eax,(%rbx)
3409     //      85 06       test   %eax,(%rsi)
3410     //      85 07       test   %eax,(%rdi)
3411     //
3412     //   41 85 00       test   %eax,(%r8)
3413     //   41 85 01       test   %eax,(%r9)
3414     //   41 85 02       test   %eax,(%r10)
3415     //   41 85 03       test   %eax,(%r11)
3416     //   41 85 06       test   %eax,(%r14)
3417     //   41 85 07       test   %eax,(%r15)
3418     //
3419     //      85 04 24    test   %eax,(%rsp)
3420     //   41 85 04 24    test   %eax,(%r12)
3421     //      85 45 00    test   %eax,0x0(%rbp)
3422     //   41 85 45 00    test   %eax,0x0(%r13)
3423 
3424     __ cmpb(Address(rbx, 0), NativeTstRegMem::instruction_rex_b_prefix);
3425     __ jcc(Assembler::notEqual, no_prefix);
3426     __ addptr(rbx, 1);
3427     __ bind(no_prefix);
3428 #ifdef ASSERT
3429     __ movptr(rax, rbx); // remember where 0x85 should be, for verification below
3430 #endif
3431     // r12/r13/rsp/rbp base encoding takes 3 bytes with the following register values:
3432     // r12/rsp 0x04
3433     // r13/rbp 0x05
3434     __ movzbq(rcx, Address(rbx, 1));
3435     __ andptr(rcx, 0x07); // looking for 0x04 .. 0x05
3436     __ subptr(rcx, 4);    // looking for 0x00 .. 0x01
3437     __ cmpptr(rcx, 1);
3438     __ jcc(Assembler::above, not_special);
3439     __ addptr(rbx, 1);
3440     __ bind(not_special);
3441 #ifdef ASSERT
3442     // Verify the correct encoding of the poll we're about to skip.
3443     __ cmpb(Address(rax, 0), NativeTstRegMem::instruction_code_memXregl);
3444     __ jcc(Assembler::notEqual, bail);
3445     // Mask out the modrm bits
3446     __ testb(Address(rax, 1), NativeTstRegMem::modrm_mask);
3447     // rax encodes to 0, so if the bits are nonzero it's incorrect
3448     __ jcc(Assembler::notZero, bail);
3449 #endif
3450     // Adjust return pc forward to step over the safepoint poll instruction
3451     __ addptr(rbx, 2);
3452     __ movptr(Address(rbp, wordSize), rbx);
3453   }
3454 
3455   __ bind(no_adjust);
3456   // Normal exit, restore registers and exit.
3457   RegisterSaver::restore_live_registers(masm, save_vectors);
3458   __ ret(0);
3459 
3460 #ifdef ASSERT
3461   __ bind(bail);
3462   __ stop("Attempting to adjust pc to skip safepoint poll but the return point is not what we expected");
3463 #endif
3464 
3465   // Make sure all code is generated
3466   masm->flush();
3467 
3468   // Fill-out other meta info
3469   return SafepointBlob::create(&buffer, oop_maps, frame_size_in_words);
3470 }
3471 
3472 //
3473 // generate_resolve_blob - call resolution (static/virtual/opt-virtual/ic-miss
3474 //
3475 // Generate a stub that calls into vm to find out the proper destination
3476 // of a java call. All the argument registers are live at this point
3477 // but since this is generic code we don't know what they are and the caller
3478 // must do any gc of the args.
3479 //
3480 RuntimeStub* SharedRuntime::generate_resolve_blob(address destination, const char* name) {
3481   assert (StubRoutines::forward_exception_entry() != NULL, "must be generated before");
3482 
3483   // allocate space for the code
3484   ResourceMark rm;
3485 
3486   CodeBuffer buffer(name, 1000, 512);
3487   MacroAssembler* masm                = new MacroAssembler(&buffer);
3488 
3489   int frame_size_in_words;
3490 
3491   OopMapSet *oop_maps = new OopMapSet();
3492   OopMap* map = NULL;
3493 
3494   int start = __ offset();
3495 
3496   map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
3497 
3498   int frame_complete = __ offset();
3499 
3500   __ set_last_Java_frame(noreg, noreg, NULL);
3501 
3502   __ mov(c_rarg0, r15_thread);
3503 
3504   __ call(RuntimeAddress(destination));
3505 
3506 
3507   // Set an oopmap for the call site.
3508   // We need this not only for callee-saved registers, but also for volatile
3509   // registers that the compiler might be keeping live across a safepoint.
3510 
3511   oop_maps->add_gc_map( __ offset() - start, map);
3512 
3513   // rax contains the address we are going to jump to assuming no exception got installed
3514 
3515   // clear last_Java_sp
3516   __ reset_last_Java_frame(false);
3517   // check for pending exceptions
3518   Label pending;
3519   __ cmpptr(Address(r15_thread, Thread::pending_exception_offset()), (int32_t)NULL_WORD);
3520   __ jcc(Assembler::notEqual, pending);
3521 
3522   // get the returned Method*
3523   __ get_vm_result_2(rbx, r15_thread);
3524   __ movptr(Address(rsp, RegisterSaver::rbx_offset_in_bytes()), rbx);
3525 
3526   __ movptr(Address(rsp, RegisterSaver::rax_offset_in_bytes()), rax);
3527 
3528   RegisterSaver::restore_live_registers(masm);
3529 
3530   // We are back the the original state on entry and ready to go.
3531 
3532   __ jmp(rax);
3533 
3534   // Pending exception after the safepoint
3535 
3536   __ bind(pending);
3537 
3538   RegisterSaver::restore_live_registers(masm);
3539 
3540   // exception pending => remove activation and forward to exception handler
3541 
3542   __ movptr(Address(r15_thread, JavaThread::vm_result_offset()), (int)NULL_WORD);
3543 
3544   __ movptr(rax, Address(r15_thread, Thread::pending_exception_offset()));
3545   __ jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
3546 
3547   // -------------
3548   // make sure all code is generated
3549   masm->flush();
3550 
3551   // return the  blob
3552   // frame_size_words or bytes??
3553   return RuntimeStub::new_runtime_stub(name, &buffer, frame_complete, frame_size_in_words, oop_maps, true);
3554 }
3555 
3556 
3557 //------------------------------Montgomery multiplication------------------------
3558 //
3559 
3560 #ifndef _WINDOWS
3561 
3562 #define ASM_SUBTRACT
3563 
3564 #ifdef ASM_SUBTRACT
3565 // Subtract 0:b from carry:a.  Return carry.
3566 static unsigned long
3567 sub(unsigned long a[], unsigned long b[], unsigned long carry, long len) {
3568   long i = 0, cnt = len;
3569   unsigned long tmp;
3570   asm volatile("clc; "
3571                "0: ; "
3572                "mov (%[b], %[i], 8), %[tmp]; "
3573                "sbb %[tmp], (%[a], %[i], 8); "
3574                "inc %[i]; dec %[cnt]; "
3575                "jne 0b; "
3576                "mov %[carry], %[tmp]; sbb $0, %[tmp]; "
3577                : [i]"+r"(i), [cnt]"+r"(cnt), [tmp]"=&r"(tmp)
3578                : [a]"r"(a), [b]"r"(b), [carry]"r"(carry)
3579                : "memory");
3580   return tmp;
3581 }
3582 #else // ASM_SUBTRACT
3583 typedef int __attribute__((mode(TI))) int128;
3584 
3585 // Subtract 0:b from carry:a.  Return carry.
3586 static unsigned long
3587 sub(unsigned long a[], unsigned long b[], unsigned long carry, int len) {
3588   int128 tmp = 0;
3589   int i;
3590   for (i = 0; i < len; i++) {
3591     tmp += a[i];
3592     tmp -= b[i];
3593     a[i] = tmp;
3594     tmp >>= 64;
3595     assert(-1 <= tmp && tmp <= 0, "invariant");
3596   }
3597   return tmp + carry;
3598 }
3599 #endif // ! ASM_SUBTRACT
3600 
3601 // Multiply (unsigned) Long A by Long B, accumulating the double-
3602 // length result into the accumulator formed of T0, T1, and T2.
3603 #define MACC(A, B, T0, T1, T2)                                  \
3604 do {                                                            \
3605   unsigned long hi, lo;                                         \
3606   __asm__ ("mul %5; add %%rax, %2; adc %%rdx, %3; adc $0, %4"   \
3607            : "=&d"(hi), "=a"(lo), "+r"(T0), "+r"(T1), "+g"(T2)  \
3608            : "r"(A), "a"(B) : "cc");                            \
3609  } while(0)
3610 
3611 // As above, but add twice the double-length result into the
3612 // accumulator.
3613 #define MACC2(A, B, T0, T1, T2)                                 \
3614 do {                                                            \
3615   unsigned long hi, lo;                                         \
3616   __asm__ ("mul %5; add %%rax, %2; adc %%rdx, %3; adc $0, %4; " \
3617            "add %%rax, %2; adc %%rdx, %3; adc $0, %4"           \
3618            : "=&d"(hi), "=a"(lo), "+r"(T0), "+r"(T1), "+g"(T2)  \
3619            : "r"(A), "a"(B) : "cc");                            \
3620  } while(0)
3621 
3622 // Fast Montgomery multiplication.  The derivation of the algorithm is
3623 // in  A Cryptographic Library for the Motorola DSP56000,
3624 // Dusse and Kaliski, Proc. EUROCRYPT 90, pp. 230-237.
3625 
3626 static void __attribute__((noinline))
3627 montgomery_multiply(unsigned long a[], unsigned long b[], unsigned long n[],
3628                     unsigned long m[], unsigned long inv, int len) {
3629   unsigned long t0 = 0, t1 = 0, t2 = 0; // Triple-precision accumulator
3630   int i;
3631 
3632   assert(inv * n[0] == -1UL, "broken inverse in Montgomery multiply");
3633 
3634   for (i = 0; i < len; i++) {
3635     int j;
3636     for (j = 0; j < i; j++) {
3637       MACC(a[j], b[i-j], t0, t1, t2);
3638       MACC(m[j], n[i-j], t0, t1, t2);
3639     }
3640     MACC(a[i], b[0], t0, t1, t2);
3641     m[i] = t0 * inv;
3642     MACC(m[i], n[0], t0, t1, t2);
3643 
3644     assert(t0 == 0, "broken Montgomery multiply");
3645 
3646     t0 = t1; t1 = t2; t2 = 0;
3647   }
3648 
3649   for (i = len; i < 2*len; i++) {
3650     int j;
3651     for (j = i-len+1; j < len; j++) {
3652       MACC(a[j], b[i-j], t0, t1, t2);
3653       MACC(m[j], n[i-j], t0, t1, t2);
3654     }
3655     m[i-len] = t0;
3656     t0 = t1; t1 = t2; t2 = 0;
3657   }
3658 
3659   while (t0)
3660     t0 = sub(m, n, t0, len);
3661 }
3662 
3663 // Fast Montgomery squaring.  This uses asymptotically 25% fewer
3664 // multiplies so it should be up to 25% faster than Montgomery
3665 // multiplication.  However, its loop control is more complex and it
3666 // may actually run slower on some machines.
3667 
3668 static void __attribute__((noinline))
3669 montgomery_square(unsigned long a[], unsigned long n[],
3670                   unsigned long m[], unsigned long inv, int len) {
3671   unsigned long t0 = 0, t1 = 0, t2 = 0; // Triple-precision accumulator
3672   int i;
3673 
3674   assert(inv * n[0] == -1UL, "broken inverse in Montgomery multiply");
3675 
3676   for (i = 0; i < len; i++) {
3677     int j;
3678     int end = (i+1)/2;
3679     for (j = 0; j < end; j++) {
3680       MACC2(a[j], a[i-j], t0, t1, t2);
3681       MACC(m[j], n[i-j], t0, t1, t2);
3682     }
3683     if ((i & 1) == 0) {
3684       MACC(a[j], a[j], t0, t1, t2);
3685     }
3686     for (; j < i; j++) {
3687       MACC(m[j], n[i-j], t0, t1, t2);
3688     }
3689     m[i] = t0 * inv;
3690     MACC(m[i], n[0], t0, t1, t2);
3691 
3692     assert(t0 == 0, "broken Montgomery square");
3693 
3694     t0 = t1; t1 = t2; t2 = 0;
3695   }
3696 
3697   for (i = len; i < 2*len; i++) {
3698     int start = i-len+1;
3699     int end = start + (len - start)/2;
3700     int j;
3701     for (j = start; j < end; j++) {
3702       MACC2(a[j], a[i-j], t0, t1, t2);
3703       MACC(m[j], n[i-j], t0, t1, t2);
3704     }
3705     if ((i & 1) == 0) {
3706       MACC(a[j], a[j], t0, t1, t2);
3707     }
3708     for (; j < len; j++) {
3709       MACC(m[j], n[i-j], t0, t1, t2);
3710     }
3711     m[i-len] = t0;
3712     t0 = t1; t1 = t2; t2 = 0;
3713   }
3714 
3715   while (t0)
3716     t0 = sub(m, n, t0, len);
3717 }
3718 
3719 // Swap words in a longword.
3720 static unsigned long swap(unsigned long x) {
3721   return (x << 32) | (x >> 32);
3722 }
3723 
3724 // Copy len longwords from s to d, word-swapping as we go.  The
3725 // destination array is reversed.
3726 static void reverse_words(unsigned long *s, unsigned long *d, int len) {
3727   d += len;
3728   while(len-- > 0) {
3729     d--;
3730     *d = swap(*s);
3731     s++;
3732   }
3733 }
3734 
3735 // The threshold at which squaring is advantageous was determined
3736 // experimentally on an i7-3930K (Ivy Bridge) CPU @ 3.5GHz.
3737 #define MONTGOMERY_SQUARING_THRESHOLD 64
3738 
3739 void SharedRuntime::montgomery_multiply(jint *a_ints, jint *b_ints, jint *n_ints,
3740                                         jint len, jlong inv,
3741                                         jint *m_ints) {
3742   assert(len % 2 == 0, "array length in montgomery_multiply must be even");
3743   int longwords = len/2;
3744 
3745   // Make very sure we don't use so much space that the stack might
3746   // overflow.  512 jints corresponds to an 16384-bit integer and
3747   // will use here a total of 8k bytes of stack space.
3748   int total_allocation = longwords * sizeof (unsigned long) * 4;
3749   guarantee(total_allocation <= 8192, "must be");
3750   unsigned long *scratch = (unsigned long *)alloca(total_allocation);
3751 
3752   // Local scratch arrays
3753   unsigned long
3754     *a = scratch + 0 * longwords,
3755     *b = scratch + 1 * longwords,
3756     *n = scratch + 2 * longwords,
3757     *m = scratch + 3 * longwords;
3758 
3759   reverse_words((unsigned long *)a_ints, a, longwords);
3760   reverse_words((unsigned long *)b_ints, b, longwords);
3761   reverse_words((unsigned long *)n_ints, n, longwords);
3762 
3763   ::montgomery_multiply(a, b, n, m, (unsigned long)inv, longwords);
3764 
3765   reverse_words(m, (unsigned long *)m_ints, longwords);
3766 }
3767 
3768 void SharedRuntime::montgomery_square(jint *a_ints, jint *n_ints,
3769                                       jint len, jlong inv,
3770                                       jint *m_ints) {
3771   assert(len % 2 == 0, "array length in montgomery_square must be even");
3772   int longwords = len/2;
3773 
3774   // Make very sure we don't use so much space that the stack might
3775   // overflow.  512 jints corresponds to an 16384-bit integer and
3776   // will use here a total of 6k bytes of stack space.
3777   int total_allocation = longwords * sizeof (unsigned long) * 3;
3778   guarantee(total_allocation <= 8192, "must be");
3779   unsigned long *scratch = (unsigned long *)alloca(total_allocation);
3780 
3781   // Local scratch arrays
3782   unsigned long
3783     *a = scratch + 0 * longwords,
3784     *n = scratch + 1 * longwords,
3785     *m = scratch + 2 * longwords;
3786 
3787   reverse_words((unsigned long *)a_ints, a, longwords);
3788   reverse_words((unsigned long *)n_ints, n, longwords);
3789 
3790   if (len >= MONTGOMERY_SQUARING_THRESHOLD) {
3791     ::montgomery_square(a, n, m, (unsigned long)inv, longwords);
3792   } else {
3793     ::montgomery_multiply(a, a, n, m, (unsigned long)inv, longwords);
3794   }
3795 
3796   reverse_words(m, (unsigned long *)m_ints, longwords);
3797 }
3798 
3799 #endif // WINDOWS
3800 
3801 #ifdef COMPILER2
3802 // This is here instead of runtime_x86_64.cpp because it uses SimpleRuntimeFrame
3803 //
3804 //------------------------------generate_exception_blob---------------------------
3805 // creates exception blob at the end
3806 // Using exception blob, this code is jumped from a compiled method.
3807 // (see emit_exception_handler in x86_64.ad file)
3808 //
3809 // Given an exception pc at a call we call into the runtime for the
3810 // handler in this method. This handler might merely restore state
3811 // (i.e. callee save registers) unwind the frame and jump to the
3812 // exception handler for the nmethod if there is no Java level handler
3813 // for the nmethod.
3814 //
3815 // This code is entered with a jmp.
3816 //
3817 // Arguments:
3818 //   rax: exception oop
3819 //   rdx: exception pc
3820 //
3821 // Results:
3822 //   rax: exception oop
3823 //   rdx: exception pc in caller or ???
3824 //   destination: exception handler of caller
3825 //
3826 // Note: the exception pc MUST be at a call (precise debug information)
3827 //       Registers rax, rdx, rcx, rsi, rdi, r8-r11 are not callee saved.
3828 //
3829 
3830 void OptoRuntime::generate_exception_blob() {
3831   assert(!OptoRuntime::is_callee_saved_register(RDX_num), "");
3832   assert(!OptoRuntime::is_callee_saved_register(RAX_num), "");
3833   assert(!OptoRuntime::is_callee_saved_register(RCX_num), "");
3834 
3835   assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
3836 
3837   // Allocate space for the code
3838   ResourceMark rm;
3839   // Setup code generation tools
3840   CodeBuffer buffer("exception_blob", 2048, 1024);
3841   MacroAssembler* masm = new MacroAssembler(&buffer);
3842 
3843 
3844   address start = __ pc();
3845 
3846   // Exception pc is 'return address' for stack walker
3847   __ push(rdx);
3848   __ subptr(rsp, SimpleRuntimeFrame::return_off << LogBytesPerInt); // Prolog
3849 
3850   // Save callee-saved registers.  See x86_64.ad.
3851 
3852   // rbp is an implicitly saved callee saved register (i.e., the calling
3853   // convention will save/restore it in the prolog/epilog). Other than that
3854   // there are no callee save registers now that adapter frames are gone.
3855 
3856   __ movptr(Address(rsp, SimpleRuntimeFrame::rbp_off << LogBytesPerInt), rbp);
3857 
3858   // Store exception in Thread object. We cannot pass any arguments to the
3859   // handle_exception call, since we do not want to make any assumption
3860   // about the size of the frame where the exception happened in.
3861   // c_rarg0 is either rdi (Linux) or rcx (Windows).
3862   __ movptr(Address(r15_thread, JavaThread::exception_oop_offset()),rax);
3863   __ movptr(Address(r15_thread, JavaThread::exception_pc_offset()), rdx);
3864 
3865   // This call does all the hard work.  It checks if an exception handler
3866   // exists in the method.
3867   // If so, it returns the handler address.
3868   // If not, it prepares for stack-unwinding, restoring the callee-save
3869   // registers of the frame being removed.
3870   //
3871   // address OptoRuntime::handle_exception_C(JavaThread* thread)
3872 
3873   // At a method handle call, the stack may not be properly aligned
3874   // when returning with an exception.
3875   address the_pc = __ pc();
3876   __ set_last_Java_frame(noreg, noreg, the_pc);
3877   __ mov(c_rarg0, r15_thread);
3878   __ andptr(rsp, -(StackAlignmentInBytes));    // Align stack
3879   __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, OptoRuntime::handle_exception_C)));
3880 
3881   // Set an oopmap for the call site.  This oopmap will only be used if we
3882   // are unwinding the stack.  Hence, all locations will be dead.
3883   // Callee-saved registers will be the same as the frame above (i.e.,
3884   // handle_exception_stub), since they were restored when we got the
3885   // exception.
3886 
3887   OopMapSet* oop_maps = new OopMapSet();
3888 
3889   oop_maps->add_gc_map(the_pc - start, new OopMap(SimpleRuntimeFrame::framesize, 0));
3890 
3891   __ reset_last_Java_frame(false);
3892 
3893   // Restore callee-saved registers
3894 
3895   // rbp is an implicitly saved callee-saved register (i.e., the calling
3896   // convention will save restore it in prolog/epilog) Other than that
3897   // there are no callee save registers now that adapter frames are gone.
3898 
3899   __ movptr(rbp, Address(rsp, SimpleRuntimeFrame::rbp_off << LogBytesPerInt));
3900 
3901   __ addptr(rsp, SimpleRuntimeFrame::return_off << LogBytesPerInt); // Epilog
3902   __ pop(rdx);                  // No need for exception pc anymore
3903 
3904   // rax: exception handler
3905 
3906   // We have a handler in rax (could be deopt blob).
3907   __ mov(r8, rax);
3908 
3909   // Get the exception oop
3910   __ movptr(rax, Address(r15_thread, JavaThread::exception_oop_offset()));
3911   // Get the exception pc in case we are deoptimized
3912   __ movptr(rdx, Address(r15_thread, JavaThread::exception_pc_offset()));
3913 #ifdef ASSERT
3914   __ movptr(Address(r15_thread, JavaThread::exception_handler_pc_offset()), (int)NULL_WORD);
3915   __ movptr(Address(r15_thread, JavaThread::exception_pc_offset()), (int)NULL_WORD);
3916 #endif
3917   // Clear the exception oop so GC no longer processes it as a root.
3918   __ movptr(Address(r15_thread, JavaThread::exception_oop_offset()), (int)NULL_WORD);
3919 
3920   // rax: exception oop
3921   // r8:  exception handler
3922   // rdx: exception pc
3923   // Jump to handler
3924 
3925   __ jmp(r8);
3926 
3927   // Make sure all code is generated
3928   masm->flush();
3929 
3930   // Set exception blob
3931   _exception_blob =  ExceptionBlob::create(&buffer, oop_maps, SimpleRuntimeFrame::framesize >> 1);
3932 }
3933 #endif // COMPILER2