1 /*
   2  * Copyright (c) 2003, 2012, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2014, Red Hat Inc. All rights reserved.
   4  * Copyright (c) 2015, Linaro Ltd. All rights reserved.
   5  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   6  *
   7  * This code is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License version 2 only, as
   9  * published by the Free Software Foundation.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  *
  25  */
  26 
  27 #include "precompiled.hpp"
  28 #include "asm/macroAssembler.hpp"
  29 #include "asm/macroAssembler.inline.hpp"
  30 #include "code/debugInfoRec.hpp"
  31 #include "code/icBuffer.hpp"
  32 #include "code/vtableStubs.hpp"
  33 #include "interp_masm_aarch32.hpp"
  34 #include "interpreter/interpreter.hpp"
  35 #include "oops/compiledICHolder.hpp"
  36 #include "prims/jvmtiRedefineClassesTrace.hpp"
  37 #include "runtime/sharedRuntime.hpp"
  38 #include "runtime/vframeArray.hpp"
  39 #include "vmreg_aarch32.inline.hpp"
  40 #ifdef COMPILER1
  41 #include "c1/c1_Runtime1.hpp"
  42 #endif
  43 #ifdef COMPILER2
  44 #include "adfiles/ad_aarch32.hpp"
  45 #include "opto/runtime.hpp"
  46 #endif
  47 
  48 
  49 #define __ masm->
  50 
  51 const int StackAlignmentInSlots = StackAlignmentInBytes / VMRegImpl::stack_slot_size;
  52 
  53 class SimpleRuntimeFrame {
  54 
  55   public:
  56 
  57   // Most of the runtime stubs have this simple frame layout.
  58   // This class exists to make the layout shared in one place.
  59   // Offsets are for compiler stack slots, which are jints.
  60   enum layout {
  61     // The frame sender code expects that rbp will be in the "natural" place and
  62     // will override any oopMap setting for it. We must therefore force the layout
  63     // so that it agrees with the frame sender code.
  64     // we don't expect any arg reg save area so aarch32 asserts that
  65     // frame::arg_reg_save_area_bytes == 0
  66     rbp_off = 0,
  67     rbp_off2,
  68     return_off, return_off2,
  69     framesize
  70   };
  71 };
  72 
  73 // FIXME -- this is used by C1
  74 class RegisterSaver {
  75  public:
  76   static OopMap* save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words);
  77   static void restore_live_registers(MacroAssembler* masm);
  78 
  79   // Capture info about frame layout
  80   enum layout {
  81       fpu_state_off = 0,
  82       fpu_state_end = fpu_state_off+FPUStateSizeInWords-1,
  83       // The frame sender code expects that rfp will be in
  84       // the "natural" place and will override any oopMap
  85       // setting for it. We must therefore force the layout
  86       // so that it agrees with the frame sender code.
  87       //
  88       // FIXME there are extra saved register (from `push_CPU_state`) note that r11 == rfp
  89       r0_off,
  90       r1_off,
  91       r2_off,
  92       r3_off,
  93       r4_off,
  94       r5_off,
  95       r6_off,
  96       r7_off,
  97       r8_off,
  98       r9_off,  rscratch1_off = r9_off,
  99       r10_off, rmethod_off = r10_off,
 100       r11_off,
 101       r12_off,
 102       reg_save_pad, // align area to 8-bytes to simplify stack alignment to 8
 103       rfp_off,
 104       return_off,
 105       reg_save_size,
 106   };
 107 
 108 
 109   // Offsets into the register save area
 110   // Used by deoptimization when it is managing result register
 111   // values on its own
 112 
 113   static int offset_in_bytes(int offset)    { return offset * wordSize; }
 114 
 115 // During deoptimization only the result registers need to be restored,
 116   // all the other values have already been extracted.
 117   static void restore_result_registers(MacroAssembler* masm);
 118 
 119 };
 120 
 121 OopMap* RegisterSaver::save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words) {
 122   int frame_size_in_bytes = additional_frame_words*wordSize + reg_save_size*BytesPerInt;
 123   int frame_size_in_slots = frame_size_in_bytes / BytesPerInt;
 124   int additional_frame_slots = additional_frame_words*wordSize / BytesPerInt;
 125   *total_frame_words = frame_size_in_bytes / wordSize;;
 126 
 127   __ enter();
 128   __ push_CPU_state();
 129 
 130   // Set an oopmap for the call site.  This oopmap will map all
 131   // oop-registers and debug-info registers as callee-saved.  This
 132   // will allow deoptimization at this safepoint to find all possible
 133   // debug-info recordings, as well as let GC find all oops.
 134 
 135   OopMapSet *oop_maps = new OopMapSet();
 136   OopMap* oop_map = new OopMap(frame_size_in_slots, 0);
 137 
 138   oop_map->set_callee_saved(VMRegImpl::stack2reg(r0_off + additional_frame_slots), r0->as_VMReg());
 139   oop_map->set_callee_saved(VMRegImpl::stack2reg(r1_off + additional_frame_slots), r1->as_VMReg());
 140   oop_map->set_callee_saved(VMRegImpl::stack2reg(r2_off + additional_frame_slots), r2->as_VMReg());
 141   oop_map->set_callee_saved(VMRegImpl::stack2reg(r3_off + additional_frame_slots), r3->as_VMReg());
 142   oop_map->set_callee_saved(VMRegImpl::stack2reg(r4_off + additional_frame_slots), r4->as_VMReg());
 143   oop_map->set_callee_saved(VMRegImpl::stack2reg(r5_off + additional_frame_slots), r5->as_VMReg());
 144   oop_map->set_callee_saved(VMRegImpl::stack2reg(r6_off + additional_frame_slots), r6->as_VMReg());
 145   oop_map->set_callee_saved(VMRegImpl::stack2reg(r7_off + additional_frame_slots), r7->as_VMReg());
 146   oop_map->set_callee_saved(VMRegImpl::stack2reg(r8_off + additional_frame_slots), r8->as_VMReg());
 147   oop_map->set_callee_saved(VMRegImpl::stack2reg(r10_off + additional_frame_slots), r10->as_VMReg());
 148   // r11 saved in frame header as rfp, not map it here
 149   // r11 & r14 have special meaning (can't hold oop), so not map them
 150 
 151   for (int i = 0; i < 31; ++i) {
 152     oop_map->set_callee_saved(VMRegImpl::stack2reg(fpu_state_off + i + additional_frame_slots),
 153     as_FloatRegister(i)->as_VMReg());
 154   }
 155 
 156   return oop_map;
 157 }
 158 
 159 void RegisterSaver::restore_live_registers(MacroAssembler* masm) {
 160   __ pop_CPU_state();
 161   __ leave();
 162 }
 163 
 164 void RegisterSaver::restore_result_registers(MacroAssembler* masm) {
 165 
 166   // Just restore result register. Only used by deoptimization. By
 167   // now any callee save register that needs to be restored to a c2
 168   // caller of the deoptee has been extracted into the vframeArray
 169   // and will be stuffed into the c2i adapter we create for later
 170   // restoration so only result registers need to be restored here.
 171 
 172 
 173 
 174   // Restore fp result register
 175   __ vldr_f64(d0, Address(sp, offset_in_bytes(fpu_state_off)));
 176   // Restore integer result register
 177   __ ldr(r0, Address(sp, offset_in_bytes(r0_off)));
 178   __ ldr(r1, Address(sp, offset_in_bytes(r1_off)));
 179 
 180   // Pop all of the register save are off the stack
 181   __ add(sp, sp, reg_save_size * wordSize);
 182 }
 183 
 184 // Is vector's size (in bytes) bigger than a size saved by default?
 185 // 16 bytes XMM registers are saved by default using fxsave/fxrstor instructions.
 186 bool SharedRuntime::is_wide_vector(int size) {
 187   return size > 16;
 188 }
 189 
 190 // This functions returns offset from fp to java arguments on stack.
 191 //
 192 // The java_calling_convention describes stack locations as ideal slots on
 193 // a frame with no abi restrictions. Since we must observe abi restrictions
 194 // (like the placement of the register window) the slots must be biased by
 195 // the following value.
 196 static int reg2offset_in(VMReg r) {
 197   // After stack frame created, fp points to 1 slot after previous sp value.
 198   return (r->reg2stack() + 1) * VMRegImpl::stack_slot_size;
 199 }
 200 
 201 static int reg2offset_out(VMReg r) {
 202   return (r->reg2stack() + SharedRuntime::out_preserve_stack_slots()) * VMRegImpl::stack_slot_size;
 203 }
 204 
 205 // ---------------------------------------------------------------------------
 206 // Read the array of BasicTypes from a signature, and compute where the
 207 // arguments should go.  Values in the VMRegPair regs array refer to 4-byte
 208 // quantities.  Values less than VMRegImpl::stack0 are registers, those above
 209 // refer to 4-byte stack slots.  All stack slots are based off of the stack pointer
 210 // as framesizes are fixed.
 211 // VMRegImpl::stack0 refers to the first slot 0(sp).
 212 // and VMRegImpl::stack0+1 refers to the memory word 4-byes higher.  Register
 213 // up to RegisterImpl::number_of_registers) are the 64-bit
 214 // integer registers.
 215 
 216 // Note: the INPUTS in sig_bt are in units of Java argument words,
 217 // which are 64-bit.  The OUTPUTS are in 32-bit units.
 218 
 219 // The Java calling convention is a "shifted" version of the C ABI.
 220 // By skipping the first C ABI register we can call non-static jni
 221 // methods with small numbers of arguments without having to shuffle
 222 // the arguments at all. Since we control the java ABI we ought to at
 223 // least get some advantage out of it.
 224 
 225 int SharedRuntime::java_calling_convention(const BasicType *sig_bt,
 226                                            VMRegPair *regs,
 227                                            int total_args_passed,
 228                                            int is_outgoing) {
 229 
 230   // Create the mapping between argument positions and
 231   // registers.
 232   static const Register INT_ArgReg[Argument::n_int_register_parameters_j] = {
 233     j_rarg0, j_rarg1, j_rarg2, j_rarg3
 234   };
 235   const int FP_ArgReg_N = 16;
 236   static const FloatRegister FP_ArgReg[] = {
 237     f0, f1, f2, f3,
 238     f4, f5, f6, f7,
 239     f8, f9, f10, f11,
 240     f12, f13, f14, f15,
 241   };
 242 
 243   uint int_args = 0;
 244   uint fp_args = 0;
 245   uint stk_args = 0;
 246 
 247   for (int i = 0; i < total_args_passed; i++) {
 248     switch (sig_bt[i]) {
 249     case T_BOOLEAN:
 250     case T_CHAR:
 251     case T_BYTE:
 252     case T_SHORT:
 253     case T_INT:
 254     case T_OBJECT:
 255     case T_ARRAY:
 256     case T_ADDRESS:
 257       if (int_args < Argument::n_int_register_parameters_j) {
 258         regs[i].set1(INT_ArgReg[int_args++]->as_VMReg());
 259       } else {
 260         regs[i].set1(VMRegImpl::stack2reg(stk_args));
 261         stk_args += 1;
 262       }
 263       break;
 264     case T_VOID:
 265       // halves of T_LONG or T_DOUBLE
 266       assert(i != 0 && (sig_bt[i - 1] == T_LONG || sig_bt[i - 1] == T_DOUBLE), "expecting half");
 267       regs[i].set_bad();
 268       break;
 269     case T_LONG:
 270       assert(sig_bt[i + 1] == T_VOID, "expecting half");
 271       if (int_args + 1 < Argument::n_int_register_parameters_j) {
 272         regs[i].set_pair(INT_ArgReg[int_args + 1]->as_VMReg(), INT_ArgReg[int_args]->as_VMReg());
 273         int_args += 2;
 274       } else {
 275         regs[i].set2(VMRegImpl::stack2reg(stk_args));
 276         stk_args += 2;
 277       }
 278       break;
 279     case T_FLOAT:
 280       if (fp_args < FP_ArgReg_N) {
 281         regs[i].set1(FP_ArgReg[fp_args++]->as_VMReg());
 282       } else {
 283         regs[i].set1(VMRegImpl::stack2reg(stk_args));
 284         stk_args += 1;
 285       }
 286       break;
 287     case T_DOUBLE:
 288       assert(sig_bt[i + 1] == T_VOID, "expecting half");
 289       fp_args = round_to(fp_args, 2);
 290       if (fp_args < FP_ArgReg_N) {
 291         regs[i].set2(FP_ArgReg[fp_args]->as_VMReg());
 292         fp_args += 2;
 293       } else {
 294         regs[i].set2(VMRegImpl::stack2reg(stk_args));
 295         stk_args += 2;
 296       }
 297       break;
 298     default:
 299       ShouldNotReachHere();
 300       break;
 301     }
 302   }
 303 
 304   return round_to(stk_args, StackAlignmentInBytes/wordSize);
 305 }
 306 
 307 // Patch the callers callsite with entry to compiled code if it exists.
 308 static void patch_callers_callsite(MacroAssembler *masm) {
 309   Label L;
 310   __ ldr(rscratch1, Address(rmethod, in_bytes(Method::code_offset())));
 311   __ cbz(rscratch1, L);
 312 
 313   __ enter();
 314   __ push_CPU_state();
 315 
 316   // VM needs caller's callsite
 317   // VM needs target method
 318   // This needs to be a long call since we will relocate this adapter to
 319   // the codeBuffer and it may not reach
 320 
 321 #ifndef PRODUCT
 322   assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
 323 #endif
 324 
 325   __ mov(c_rarg0, rmethod);
 326   __ mov(c_rarg1, lr);
 327   __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::fixup_callers_callsite)));
 328   __ bl(rscratch1);
 329   __ maybe_isb();
 330 
 331   __ pop_CPU_state();
 332   // restore sp
 333   __ leave();
 334   __ bind(L);
 335 }
 336 
 337 static void gen_c2i_adapter(MacroAssembler *masm,
 338                             int total_args_passed,
 339                             int comp_args_on_stack,
 340                             const BasicType *sig_bt,
 341                             const VMRegPair *regs,
 342                             Label& skip_fixup) {
 343   // Before we get into the guts of the C2I adapter, see if we should be here
 344   // at all.  We've come from compiled code and are attempting to jump to the
 345   // interpreter, which means the caller made a static call to get here
 346   // (vcalls always get a compiled target if there is one).  Check for a
 347   // compiled target.  If there is one, we need to patch the caller's call.
 348   patch_callers_callsite(masm);
 349 
 350   __ bind(skip_fixup);
 351 
 352   // Since all args are passed on the stack, total_args_passed *
 353   // Interpreter::stackElementSize is the space we need.
 354 
 355   const int extraspace = total_args_passed * Interpreter::stackElementSize;
 356   const Register compArgPos = lr;
 357   int ld_shift = 0;
 358 
 359   __ str(compArgPos, Address(sp, -(extraspace + wordSize)));
 360   __ mov(compArgPos, sp);
 361 
 362   // Now write the args into the outgoing interpreter space
 363   for (int i = 0; i < total_args_passed; i++) {
 364 
 365     if (sig_bt[i] == T_VOID) {
 366       assert(i > 0 && (sig_bt[i-1] == T_LONG || sig_bt[i-1] == T_DOUBLE), "missing half");
 367       continue;
 368     }
 369 
 370     // next stack slot offset
 371     const int next_off = -Interpreter::stackElementSize;
 372 
 373     VMReg r_1 = regs[i].first();
 374     VMReg r_2 = regs[i].second();
 375     if (!r_1->is_valid()) {
 376       assert(!r_2->is_valid(), "");
 377       continue;
 378     }
 379 
 380     if (r_2->is_valid()) {
 381       assert(i + 1 < total_args_passed && sig_bt[i + 1] == T_VOID, "going to overrwrite reg_2 value");
 382     }
 383 
 384     if (r_1->is_stack()) {
 385       // memory to memory use rscratch1
 386       int ld_off = r_1->reg2stack() * VMRegImpl::stack_slot_size - ld_shift;
 387       if (!r_2->is_valid()) {
 388         __ ldr(rscratch1, Address(compArgPos, ld_off));
 389         __ str(rscratch1, Address(sp, next_off, Address::pre));
 390       } else {
 391           int tmp_off = ld_off;
 392           // ldrd accepts only imm8
 393           if(abs(ld_off) > (255 << 2)) {
 394               if(__ is_valid_for_imm12(ld_off)) {
 395                 __ add(compArgPos, compArgPos, ld_off);
 396               } else {
 397                 // add operates encoded imm12, NOT plain
 398                 __ mov(rscratch1, ld_off);
 399                 __ add(compArgPos, compArgPos, rscratch1);
 400               }
 401               tmp_off = 0;
 402               ld_shift += ld_off;
 403           }
 404         __ ldrd(rscratch1, rscratch2, Address(compArgPos, tmp_off));
 405         __ strd(rscratch1, rscratch2, Address(sp, 2* next_off, Address::pre));
 406       }
 407     } else if (r_1->is_Register()) {
 408       Register r = r_1->as_Register();
 409       assert(r != compArgPos, "compArgPos was modified");
 410       if (!r_2->is_valid()) {
 411         __ str(r, Address(sp, next_off, Address::pre));
 412       } else {
 413         assert(r_2->as_Register() != compArgPos, "compArgPos was modified");
 414         __ strd(r, r_2->as_Register(), Address(sp, 2 * next_off, Address::pre));
 415       }
 416     } else {
 417       assert(r_1->is_FloatRegister(), "");
 418       if (!r_2->is_valid()) {
 419         // Can't do pre or post addressing for vldr, vstr
 420         __ add(sp, sp, next_off);
 421         __ vstr_f32(r_1->as_FloatRegister(), Address(sp));
 422       } else {
 423     // TODO assert(r_2->is_FloatRegister() && r_2->as_FloatRegister() == r_1->as_FloatRegister() + 1, "");
 424         // Can't do pre or post addressing for vldr, vstr
 425         __ add(sp, sp, 2 * next_off);
 426         __ vstr_f64(r_1->as_FloatRegister(), Address(sp));
 427       }
 428     }
 429   }
 430 
 431   // hope, sp is returned to desired value
 432   __ ldr(compArgPos, Address(sp, -wordSize));
 433 
 434   // set sender sp
 435   if(__ is_valid_for_imm12(extraspace)) {
 436     __ add(r4, sp, extraspace);
 437   } else {
 438     __ mov(rscratch1, extraspace);
 439     __ add(r4, sp, rscratch1);
 440   }
 441 
 442   __ ldr(rscratch1, Address(rmethod, in_bytes(Method::interpreter_entry_offset())));
 443   __ b(rscratch1);
 444 }
 445 
 446 static void range_check(MacroAssembler* masm, Register pc_reg, Register temp_reg,
 447                         address code_start, address code_end,
 448                         Label& L_ok) {
 449   Label L_fail;
 450   __ lea(temp_reg, ExternalAddress(code_start));
 451   __ cmp(pc_reg, temp_reg);
 452   __ b(L_fail, Assembler::LO);
 453   __ lea(temp_reg, ExternalAddress(code_end));
 454   __ cmp(pc_reg, temp_reg);
 455   __ b(L_ok, Assembler::LO);
 456   __ bind(L_fail);
 457 }
 458 
 459 static void gen_i2c_adapter(MacroAssembler *masm,
 460                             int total_args_passed,
 461                             int comp_args_on_stack,
 462                             const BasicType *sig_bt,
 463                             const VMRegPair *regs) {
 464 
 465   // Note: r13 contains the senderSP on entry. We must preserve it since
 466   // we may do a i2c -> c2i transition if we lose a race where compiled
 467   // code goes non-entrant while we get args ready.
 468 
 469   // In addition we use r13 to locate all the interpreter args because
 470   // we must align the stack to 16 bytes.
 471 
 472   // Adapters are frameless.
 473 
 474   // An i2c adapter is frameless because the *caller* frame, which is
 475   // interpreted, routinely repairs its own sp (from
 476   // interpreter_frame_last_sp), even if a callee has modified the
 477   // stack pointer.  It also recalculates and aligns sp.
 478 
 479   // A c2i adapter is frameless because the *callee* frame, which is
 480   // interpreted, routinely repairs its caller's sp (from sender_sp,
 481   // which is set up via the senderSP register).
 482 
 483   // In other words, if *either* the caller or callee is interpreted, we can
 484   // get the stack pointer repaired after a call.
 485 
 486   // This is why c2i and i2c adapters cannot be indefinitely composed.
 487   // In particular, if a c2i adapter were to somehow call an i2c adapter,
 488   // both caller and callee would be compiled methods, and neither would
 489   // clean up the stack pointer changes performed by the two adapters.
 490   // If this happens, control eventually transfers back to the compiled
 491   // caller, but with an uncorrected stack, causing delayed havoc.
 492 
 493   if (VerifyAdapterCalls &&
 494       (Interpreter::code() != NULL || StubRoutines::code1() != NULL)) {
 495     // So, let's test for cascading c2i/i2c adapters right now.
 496     //  assert(Interpreter::contains($return_addr) ||
 497     //         StubRoutines::contains($return_addr),
 498     //         "i2c adapter must return to an interpreter frame");
 499     __ block_comment("verify_i2c { ");
 500     Label L_ok;
 501     if (Interpreter::code() != NULL)
 502       range_check(masm, lr, rscratch1,
 503                   Interpreter::code()->code_start(), Interpreter::code()->code_end(),
 504                   L_ok);
 505     if (StubRoutines::code1() != NULL)
 506       range_check(masm, lr, rscratch1,
 507                   StubRoutines::code1()->code_begin(), StubRoutines::code1()->code_end(),
 508                   L_ok);
 509     if (StubRoutines::code2() != NULL)
 510       range_check(masm, lr, rscratch1,
 511                   StubRoutines::code2()->code_begin(), StubRoutines::code2()->code_end(),
 512                   L_ok);
 513     const char* msg = "i2c adapter must return to an interpreter frame";
 514     __ block_comment(msg);
 515     __ stop(msg);
 516     __ bind(L_ok);
 517     __ block_comment("} verify_i2ce ");
 518   }
 519 
 520   const int stack_space = round_to(comp_args_on_stack * VMRegImpl::stack_slot_size, StackAlignmentInBytes);
 521   const int ld_high = total_args_passed *Interpreter::stackElementSize;
 522   // Point to interpreter value (vs. tag)
 523   const int next_off =  -Interpreter::stackElementSize; // offset from ld ptr
 524   const Register loadCounter = lr;
 525 
 526   // Align sp to StackAlignmentInBytes so compiled frame starts always aligned
 527   // This is required by APCS, so all native code depends on it. The compiled
 528   // Java code is not required to follow this standard however doing so
 529   // simplifies the code because allows to have fixed size for compiled frames
 530   __ mov(rscratch2, sp);
 531   __ align_stack();
 532   if(total_args_passed) {
 533     // put below reserved stack space, imm12 should be enough
 534     __ str(loadCounter, Address(sp, -(stack_space + wordSize)));
 535 
 536     if(__ is_valid_for_imm12(ld_high)) {
 537         __ add(loadCounter, rscratch2, ld_high);
 538     } else {
 539         // add operates encoded imm12, we need plain
 540         __ mov(rscratch1, ld_high);
 541         __ add(loadCounter, rscratch2, rscratch1);
 542     }
 543   }
 544 
 545   if(comp_args_on_stack) {
 546     if(__ is_valid_for_imm12(stack_space)) {
 547         __ sub(sp, sp, stack_space);
 548     } else {
 549         // add operates encoded imm12, we need plain
 550         __ mov(rscratch1, stack_space);
 551         __ sub(sp, sp, rscratch1);
 552     }
 553   }
 554 
 555   // +------+   -> r4
 556   // |   0  | \
 557   // |   1  |  \
 558   // |   2  |   - >  Load in argument order going down.
 559   // |   x  |  /
 560   // |   N  | /
 561   // +------+ -> inital sp
 562   // | pad  | maybe 1 word to align the stack to 8 bytes
 563   // |   M  | \
 564   // |   x  |  \
 565   // |   2  |    ->  Load in argument order going up.
 566   // |   1  |  /
 567   // |   0  | /
 568   // +------+ ->
 569 
 570 
 571   int sp_offset = 0;
 572 
 573   // Now generate the shuffle code.
 574   for (int i = 0; i < total_args_passed; i++) {
 575 
 576     if (sig_bt[i] == T_VOID) {
 577       assert(i > 0 && (sig_bt[i-1] == T_LONG || sig_bt[i-1] == T_DOUBLE), "missing half");
 578       continue;
 579     }
 580 
 581     // Pick up 0, 1 or 2 words from SP+offset.
 582 
 583     //
 584     //
 585     //
 586     VMReg r_1 = regs[i].first();
 587     VMReg r_2 = regs[i].second();
 588     if (!r_1->is_valid()) {
 589       assert(!r_2->is_valid(), "");
 590       continue;
 591     }
 592 
 593     if (r_2->is_valid()) {
 594       assert(i + 1 < total_args_passed && sig_bt[i + 1] == T_VOID, "going to overrwrite reg_2 value");
 595     }
 596 
 597     if (r_1->is_stack()) {
 598       // Convert stack slot to an SP offset
 599       int st_off = regs[i].first()->reg2stack()*VMRegImpl::stack_slot_size - sp_offset;
 600 
 601       if (!r_2->is_valid()) {
 602         __ ldr(rscratch2, Address(loadCounter, next_off, Address::pre));
 603         __ str(rscratch2, Address(sp, st_off));
 604       } else {
 605         int tmp_off = st_off;
 606         if(abs(st_off) > (255 << 2)) {
 607             //st_off doesn't fit imm8 required by strd
 608 
 609             if(__ is_valid_for_imm12(st_off)) {
 610                 __ add(sp, sp, st_off);
 611             } else {
 612                 // add operates encoded imm12, NOT plain
 613                 __ mov(rscratch1, st_off);
 614                 __ add(sp, sp, rscratch1);
 615             }
 616             tmp_off = 0;
 617             sp_offset += st_off;
 618         }
 619 
 620 
 621         // Interpreter local[n] == MSW, local[n+1] == LSW however locals
 622         // are accessed as negative so LSW is at LOW address
 623 
 624         // this can be a misaligned move
 625     __ ldrd(rscratch1, rscratch2, Address(loadCounter, 2 * next_off, Address::pre));
 626     __ strd(rscratch1, rscratch2, Address(sp, tmp_off));
 627       }
 628     } else if (r_1->is_Register()) {  // Register argument
 629       Register r = r_1->as_Register();
 630       assert(r != loadCounter, "loadCounter is reloaded");
 631       if (r_2->is_valid()) {
 632         assert(r_2->as_Register() != loadCounter, "loadCounter is reloaded");
 633         // this can be a misaligned move
 634         // ldrd can handle inconsecutive registers
 635         __ ldrd(r, r_2->as_Register(), Address(loadCounter, 2 * next_off, Address::pre));
 636       } else {
 637         __ ldr(r, Address(loadCounter, next_off, Address::pre));
 638       }
 639     } else {
 640       assert(r_1->is_FloatRegister(), "");
 641       if (!r_2->is_valid()) {
 642         // Can't do pre or post addressing for vldr, vstr
 643         __ add(loadCounter, loadCounter, next_off);
 644         __ vldr_f32(r_1->as_FloatRegister(), Address(loadCounter));
 645       } else {
 646     // TODO assert(r_2->is_FloatRegister() && r_2->as_FloatRegister() == r_1->as_FloatRegister() + 1, "");
 647         // Can't do pre or post addressing for vldr, vstr
 648         __ add(loadCounter, loadCounter, 2 * next_off);
 649         __ vldr_f64(r_1->as_FloatRegister(), Address(loadCounter));
 650       }
 651     }
 652   }
 653 
 654   // restore sp
 655   if(sp_offset) {
 656     if(__ is_valid_for_imm12(sp_offset)) {
 657         __ sub(sp, sp, sp_offset);
 658     } else {
 659         // add operates encoded imm12, we need plain
 660         __ mov(rscratch1, sp_offset);
 661         __ sub(sp, sp, rscratch1);
 662     }
 663   }
 664 
 665   if(total_args_passed) {
 666     // restore loadCounter
 667     __ ldr(loadCounter, Address(sp, -wordSize));
 668   }
 669 
 670   // 6243940 We might end up in handle_wrong_method if
 671   // the callee is deoptimized as we race thru here. If that
 672   // happens we don't want to take a safepoint because the
 673   // caller frame will look interpreted and arguments are now
 674   // "compiled" so it is much better to make this transition
 675   // invisible to the stack walking code. Unfortunately if
 676   // we try and find the callee by normal means a safepoint
 677   // is possible. So we stash the desired callee in the thread
 678   // and the vm will find there should this case occur.
 679 
 680   __ str(rmethod, Address(rthread, JavaThread::callee_target_offset()));
 681 
 682   // Will jump to the compiled code just as if compiled code was doing it.
 683   __ ldr(rscratch1, Address(rmethod, in_bytes(Method::from_compiled_offset())));
 684   __ b(rscratch1);
 685 }
 686 
 687 // ---------------------------------------------------------------
 688 AdapterHandlerEntry* SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm,
 689                                                             int total_args_passed,
 690                                                             int comp_args_on_stack,
 691                                                             const BasicType *sig_bt,
 692                                                             const VMRegPair *regs,
 693                                                             AdapterFingerPrint* fingerprint) {
 694   address i2c_entry = __ pc();
 695   gen_i2c_adapter(masm, total_args_passed, comp_args_on_stack, sig_bt, regs);
 696 
 697   address c2i_unverified_entry = __ pc();
 698   Label skip_fixup;
 699 
 700   Label ok;
 701 
 702   Register holder = rscratch2;
 703   Register receiver = j_rarg0;
 704   Register tmp = r10;  // A call-clobbered register not used for arg passing
 705 
 706   // -------------------------------------------------------------------------
 707   // Generate a C2I adapter.  On entry we know rmethod holds the Method* during calls
 708   // to the interpreter.  The args start out packed in the compiled layout.  They
 709   // need to be unpacked into the interpreter layout.  This will almost always
 710   // require some stack space.  We grow the current (compiled) stack, then repack
 711   // the args.  We  finally end in a jump to the generic interpreter entry point.
 712   // On exit from the interpreter, the interpreter will restore our SP (lest the
 713   // compiled code, which relys solely on SP and not FP, get sick).
 714 
 715   {
 716     __ block_comment("c2i_unverified_entry {");
 717     __ load_klass(rscratch1, receiver);
 718     __ ldr(tmp, Address(holder, CompiledICHolder::holder_klass_offset()));
 719     __ cmp(rscratch1, tmp);
 720     __ ldr(rmethod, Address(holder, CompiledICHolder::holder_method_offset()));
 721     __ b(ok, Assembler::EQ);
 722     __ far_jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
 723 
 724     __ bind(ok);
 725     // Method might have been compiled since the call site was patched to
 726     // interpreted; if that is the case treat it as a miss so we can get
 727     // the call site corrected.
 728     __ ldr(rscratch1, Address(rmethod, in_bytes(Method::code_offset())));
 729     __ cbz(rscratch1, skip_fixup);
 730     __ far_jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
 731     __ block_comment("} c2i_unverified_entry");
 732   }
 733 
 734   address c2i_entry = __ pc();
 735 
 736   gen_c2i_adapter(masm, total_args_passed, comp_args_on_stack, sig_bt, regs, skip_fixup);
 737 
 738   __ flush();
 739   return AdapterHandlerLibrary::new_entry(fingerprint, i2c_entry, c2i_entry, c2i_unverified_entry);
 740 }
 741 
 742 int SharedRuntime::c_calling_convention(const BasicType *sig_bt,
 743                                          VMRegPair *regs,
 744                                          VMRegPair *regs2,
 745                                          int total_args_passed) {
 746   assert(regs2 == NULL, "not needed on AArch32");
 747 
 748 // We return the amount of VMRegImpl stack slots we need to reserve for all
 749 // the arguments NOT counting out_preserve_stack_slots.
 750 
 751     static const Register INT_ArgReg[Argument::n_int_register_parameters_c] = {
 752       c_rarg0, c_rarg1, c_rarg2, c_rarg3
 753     };
 754     const int FP_ArgReg_N = 16;
 755     static const FloatRegister FP_ArgReg[] = {
 756       f0, f1, f2, f3,
 757       f4, f5, f6, f7,
 758       f8, f9, f10, f11,
 759       f12, f13, f14, f15,
 760     };
 761     unsigned long fp_free_mask = (1 << FP_ArgReg_N) - 1;
 762 
 763     uint int_args = 0;
 764     uint fp_args = 0;
 765     uint stk_args = 0;
 766 
 767     for (int i = 0; i < total_args_passed; i++) {
 768       switch (sig_bt[i]) {
 769       case T_BOOLEAN:
 770       case T_CHAR:
 771       case T_BYTE:
 772       case T_SHORT:
 773       case T_INT:
 774       case T_OBJECT:
 775       case T_ARRAY:
 776       case T_ADDRESS:
 777       case T_METADATA:
 778         if (int_args < Argument::n_int_register_parameters_c) {
 779           regs[i].set1(INT_ArgReg[int_args++]->as_VMReg());
 780         } else {
 781           regs[i].set1(VMRegImpl::stack2reg(stk_args));
 782           stk_args += 1;
 783         }
 784         break;
 785       case T_LONG:
 786         assert(sig_bt[i + 1] == T_VOID, "expecting half");
 787         if (int_args + 1 < Argument::n_int_register_parameters_c) {
 788           if ((int_args % 2) != 0) {
 789             ++int_args;
 790           }
 791           regs[i].set2(INT_ArgReg[int_args]->as_VMReg());
 792           int_args += 2;
 793         } else {
 794           if (stk_args % 2 != 0) {
 795             ++stk_args;
 796           }
 797           regs[i].set2(VMRegImpl::stack2reg(stk_args));
 798           stk_args += 2;
 799           int_args = Argument::n_int_register_parameters_c;
 800         }
 801         break;
 802       case T_FLOAT:
 803         if (fp_free_mask & ((1 << FP_ArgReg_N)-1)) {
 804           unsigned index = __builtin_ctz(fp_free_mask);
 805           regs[i].set1(FP_ArgReg[index]->as_VMReg());
 806           fp_free_mask &= ~(1 << index);
 807           fp_args += 2 * ((~index) & 1);
 808         } else {
 809           regs[i].set1(VMRegImpl::stack2reg(stk_args));
 810           stk_args += 1;
 811         }
 812         break;
 813       case T_DOUBLE:
 814         assert(sig_bt[i + 1] == T_VOID, "expecting half");
 815         if (fp_args + 1 < FP_ArgReg_N) {
 816           fp_free_mask &= ~(3 << fp_args);
 817           regs[i].set2(FP_ArgReg[fp_args]->as_VMReg());
 818           fp_args += 2;
 819         } else {
 820           regs[i].set2(VMRegImpl::stack2reg(stk_args));
 821           stk_args += 2;
 822         }
 823         break;
 824       case T_VOID: // Halves of longs and doubles
 825         assert(i != 0 && (sig_bt[i - 1] == T_LONG || sig_bt[i - 1] == T_DOUBLE), "expecting half");
 826         regs[i].set_bad();
 827         break;
 828       default:
 829         ShouldNotReachHere();
 830         break;
 831       }
 832     }
 833 
 834   return round_to(stk_args, StackAlignmentInBytes/wordSize);
 835 }
 836 
 837 // On 64 bit we will store integer like items to the stack as
 838 // 64 bits items (sparc abi) even though java would only store
 839 // 32bits for a parameter. On 32bit it will simply be 32 bits
 840 // So this routine will do 32->32 on 32bit and 32->64 on 64bit
 841 
 842 static void move_int(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
 843   if (src.first()->is_stack()) {
 844     if (dst.first()->is_stack()) {
 845       // stack to stack
 846       __ ldr(rscratch1, Address(rfp, reg2offset_in(src.first())));
 847       __ str(rscratch1, Address(sp, reg2offset_out(dst.first())));
 848     } else {
 849       // stack to reg
 850       __ ldr(dst.first()->as_Register(), Address(rfp, reg2offset_in(src.first())));
 851     }
 852   } else if (dst.first()->is_stack()) {
 853     // reg to stack
 854     __ str(src.first()->as_Register(), Address(sp, reg2offset_out(dst.first())));
 855   } else {
 856     if (dst.first() != src.first()) {
 857       __ mov(dst.first()->as_Register(), src.first()->as_Register());
 858     }
 859   }
 860 }
 861 
 862 // An oop arg. Must pass a handle not the oop itself
 863 static void object_move(MacroAssembler* masm,
 864                         OopMap* map,
 865                         int oop_handle_offset,
 866                         int framesize_in_slots,
 867                         VMRegPair src,
 868                         VMRegPair dst,
 869                         bool is_receiver,
 870                         int* receiver_offset) {
 871 
 872   // must pass a handle. First figure out the location we use as a handle
 873 
 874   Register rHandle = dst.first()->is_stack() ? rscratch2 : dst.first()->as_Register();
 875 
 876   // See if oop is NULL if it is we need no handle
 877 
 878   if (src.first()->is_stack()) {
 879 
 880     // Oop is already on the stack as an argument
 881     int offset_in_older_frame = src.first()->reg2stack() + SharedRuntime::out_preserve_stack_slots();
 882     map->set_oop(VMRegImpl::stack2reg(offset_in_older_frame + framesize_in_slots));
 883     if (is_receiver) {
 884       *receiver_offset = (offset_in_older_frame + framesize_in_slots) * VMRegImpl::stack_slot_size;
 885     }
 886 
 887     __ ldr(rscratch1, Address(rfp, reg2offset_in(src.first())));
 888     __ lea(rHandle, Address(rfp, reg2offset_in(src.first())));
 889     // conditionally move a NULL
 890     __ cmp(rscratch1, 0);
 891     __ mov(rHandle, 0, Assembler::EQ);
 892   } else {
 893 
 894     // Oop is in an a register we must store it to the space we reserve
 895     // on the stack for oop_handles and pass a handle if oop is non-NULL
 896 
 897     const Register rOop = src.first()->as_Register();
 898     int oop_slot;
 899     if (rOop == j_rarg0)
 900       oop_slot = 0;
 901     else if (rOop == j_rarg1)
 902       oop_slot = 1;
 903     else if (rOop == j_rarg2)
 904       oop_slot = 2;
 905     else {
 906       assert(rOop == j_rarg3, "wrong register");
 907       oop_slot = 3;
 908     }
 909 
 910     oop_slot = oop_slot * VMRegImpl::slots_per_word + oop_handle_offset;
 911     int offset = oop_slot*VMRegImpl::stack_slot_size;
 912 
 913     map->set_oop(VMRegImpl::stack2reg(oop_slot));
 914     // Store oop in handle area, may be NULL
 915     __ str(rOop, Address(sp, offset));
 916     if (is_receiver) {
 917       *receiver_offset = offset;
 918     }
 919 
 920     __ cmp(rOop, 0);
 921     __ lea(rHandle, Address(sp, offset));
 922     // conditionally move a NULL
 923     __ mov(rHandle, 0, Assembler::EQ);
 924   }
 925 
 926   // If arg is on the stack then place it otherwise it is already in correct reg.
 927   if (dst.first()->is_stack()) {
 928     __ str(rHandle, Address(sp, reg2offset_out(dst.first())));
 929   }
 930 }
 931 
 932 // A float arg may have to do float reg int reg conversion
 933 static void float_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
 934   if (src.first()->is_stack()) {
 935     if (dst.first()->is_stack()) {
 936       // stack to stack
 937       // Have no vfp scratch registers, so copy via gpr
 938       __ ldr(rscratch1, Address(rfp, reg2offset_in(src.first())));
 939       __ str(rscratch1, Address(sp, reg2offset_out(dst.first())));
 940     } else {
 941       // stack to reg
 942       __ vldr_f32(dst.first()->as_FloatRegister(), Address(rfp, reg2offset_in(src.first())));
 943     }
 944   } else if (dst.first()->is_stack()) {
 945     // reg to stack
 946     __ vstr_f32(src.first()->as_FloatRegister(), Address(sp, reg2offset_out(dst.first())));
 947   } else {
 948     if (dst.first() != src.first()) {
 949       __ vmov_f32(dst.first()->as_FloatRegister(), src.first()->as_FloatRegister());
 950     }
 951   }
 952 }
 953 
 954 // A long move
 955 static void long_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
 956   if (src.first()->is_stack()) {
 957     if (dst.first()->is_stack()) {
 958       // stack to stack
 959       __ ldrd(rscratch1, rscratch2, Address(rfp, reg2offset_in(src.first())));
 960       __ strd(rscratch1, rscratch2, Address(sp, reg2offset_out(dst.first())));
 961     } else {
 962       // stack to reg
 963       __ ldrd(dst.first()->as_Register(), dst.second()->as_Register(),
 964       Address(rfp, reg2offset_in(src.first())));
 965     }
 966   } else if (dst.first()->is_stack()) {
 967     // reg to stack
 968     __ strd(src.first()->as_Register(), src.second()->as_Register(),
 969     Address(sp, reg2offset_out(dst.first())));
 970   } else {
 971     // reg to reg
 972     if (dst.first() != src.first()) {
 973       if (dst.first() != src.second()) {
 974         __ mov(dst.first()->as_Register(), src.first()->as_Register());
 975         __ mov(dst.second()->as_Register(), src.second()->as_Register());
 976       } else {
 977         __ mov(dst.second()->as_Register(), src.second()->as_Register());
 978         __ mov(dst.first()->as_Register(), src.first()->as_Register());
 979       }
 980     }
 981   }
 982 }
 983 
 984 // A double move
 985 static void double_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
 986   if (src.first()->is_stack()) {
 987     if (dst.first()->is_stack()) {
 988       // stack to stack
 989       // Have no vfp scratch registers, so copy via gpr
 990       __ ldrd(rscratch1, rscratch2, Address(rfp, reg2offset_in(src.first())));
 991       __ strd(rscratch1, rscratch2, Address(sp, reg2offset_out(dst.first())));
 992     } else {
 993       // stack to reg
 994       __ vldr_f64(dst.first()->as_FloatRegister(), Address(rfp, reg2offset_in(src.first())));
 995     }
 996   } else if (dst.first()->is_stack()) {
 997     // reg to stack
 998     __ vstr_f64(src.first()->as_FloatRegister(), Address(sp, reg2offset_out(dst.first())));
 999   } else {
1000     if (dst.first() != src.first()) {
1001       __ vmov_f64(dst.first()->as_FloatRegister(), src.first()->as_FloatRegister());
1002     }
1003   }
1004 }
1005 
1006 
1007 void SharedRuntime::save_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {
1008   // We always ignore the frame_slots arg and just use the space just below frame pointer
1009   // which by this time is free to use
1010   switch (ret_type) {
1011   case T_FLOAT:
1012     __ vstr_f32(f0, Address(rfp, -2 * wordSize));
1013     break;
1014   case T_DOUBLE:
1015     __ vstr_f64(d0, Address(rfp, -3 * wordSize));
1016     break;
1017   case T_LONG:
1018     __ strd(r0, r1, Address(rfp, -3 * wordSize));
1019     break;
1020   case T_VOID:
1021     break;
1022   default:
1023     __ str(r0, Address(rfp, -2 * wordSize));
1024     break;
1025   }
1026 }
1027 
1028 void SharedRuntime::restore_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {
1029   // We always ignore the frame_slots arg and just use the space just below frame pointer
1030   // which by this time is free to use
1031   switch (ret_type) {
1032   case T_FLOAT:
1033     __ vldr_f32(d0, Address(rfp, -2 * wordSize));
1034     break;
1035   case T_DOUBLE:
1036     __ vldr_f64(d0, Address(rfp, -3 * wordSize));
1037     break;
1038   case T_LONG:
1039     __ ldrd(r0, r1, Address(rfp, -3 * wordSize));
1040     break;
1041   case T_VOID:
1042     break;
1043   default:
1044     __ ldr(r0, Address(rfp, -2 * wordSize));
1045     break;
1046   }
1047 }
1048 
1049 static void save_args(MacroAssembler *masm, int arg_count, int first_arg, VMRegPair *args) {
1050   RegSet x;
1051   for ( int i = first_arg ; i < arg_count ; i++ ) {
1052     if (args[i].first()->is_Register()) {
1053       x = x + args[i].first()->as_Register();
1054     } else if (args[i].first()->is_FloatRegister()) {
1055       FloatRegister fr = args[i].first()->as_FloatRegister();
1056 
1057       if (args[i].second()->is_FloatRegister()) {
1058     assert(args[i].is_single_phys_reg(), "doubles should be 2 consequents float regs");
1059         __ decrement(sp, 2 * wordSize);
1060     __ vstr_f64(fr, Address(sp));
1061       } else {
1062         __ decrement(sp, wordSize);
1063     __ vstr_f32(fr, Address(sp));
1064       }
1065     }
1066   }
1067   __ push(x, sp);
1068 }
1069 
1070 static void restore_args(MacroAssembler *masm, int arg_count, int first_arg, VMRegPair *args) {
1071   RegSet x;
1072   for ( int i = first_arg ; i < arg_count ; i++ ) {
1073     if (args[i].first()->is_Register()) {
1074       x = x + args[i].first()->as_Register();
1075     } else {
1076       ;
1077     }
1078   }
1079   __ pop(x, sp);
1080   for ( int i = first_arg ; i < arg_count ; i++ ) {
1081     if (args[i].first()->is_Register()) {
1082       ;
1083     } else if (args[i].first()->is_FloatRegister()) {
1084       FloatRegister fr = args[i].first()->as_FloatRegister();
1085 
1086       if (args[i].second()->is_FloatRegister()) {
1087     assert(args[i].is_single_phys_reg(), "doubles should be 2 consequents float regs");
1088     __ vstr_f64(fr, Address(sp));
1089         __ increment(sp, 2 * wordSize);
1090       } else {
1091     __ vstr_f32(fr, Address(sp));
1092         __ increment(sp, wordSize);
1093       }
1094     }
1095   }
1096 }
1097 
1098 
1099 // Check GC_locker::needs_gc and enter the runtime if it's true.  This
1100 // keeps a new JNI critical region from starting until a GC has been
1101 // forced.  Save down any oops in registers and describe them in an
1102 // OopMap.
1103 static void check_needs_gc_for_critical_native(MacroAssembler* masm,
1104                                                int stack_slots,
1105                                                int total_c_args,
1106                                                int total_in_args,
1107                                                int arg_save_area,
1108                                                OopMapSet* oop_maps,
1109                                                VMRegPair* in_regs,
1110                                                BasicType* in_sig_bt) { Unimplemented(); }
1111 
1112 // Unpack an array argument into a pointer to the body and the length
1113 // if the array is non-null, otherwise pass 0 for both.
1114 static void unpack_array_argument(MacroAssembler* masm, VMRegPair reg, BasicType in_elem_type, VMRegPair body_arg, VMRegPair length_arg) { Unimplemented(); }
1115 
1116 
1117 class ComputeMoveOrder: public StackObj {
1118   class MoveOperation: public ResourceObj {
1119     friend class ComputeMoveOrder;
1120    private:
1121     VMRegPair        _src;
1122     VMRegPair        _dst;
1123     int              _src_index;
1124     int              _dst_index;
1125     bool             _processed;
1126     MoveOperation*  _next;
1127     MoveOperation*  _prev;
1128 
1129     static int get_id(VMRegPair r) { Unimplemented(); return 0; }
1130 
1131    public:
1132     MoveOperation(int src_index, VMRegPair src, int dst_index, VMRegPair dst):
1133       _src(src)
1134     , _src_index(src_index)
1135     , _dst(dst)
1136     , _dst_index(dst_index)
1137     , _next(NULL)
1138     , _prev(NULL)
1139     , _processed(false) { Unimplemented(); }
1140 
1141     VMRegPair src() const              { Unimplemented(); return _src; }
1142     int src_id() const                 { Unimplemented(); return 0; }
1143     int src_index() const              { Unimplemented(); return 0; }
1144     VMRegPair dst() const              { Unimplemented(); return _src; }
1145     void set_dst(int i, VMRegPair dst) { Unimplemented(); }
1146     int dst_index() const              { Unimplemented(); return 0; }
1147     int dst_id() const                 { Unimplemented(); return 0; }
1148     MoveOperation* next() const        { Unimplemented(); return 0; }
1149     MoveOperation* prev() const        { Unimplemented(); return 0; }
1150     void set_processed()               { Unimplemented(); }
1151     bool is_processed() const          { Unimplemented(); return 0; }
1152 
1153     // insert
1154     void break_cycle(VMRegPair temp_register) { Unimplemented(); }
1155 
1156     void link(GrowableArray<MoveOperation*>& killer) { Unimplemented(); }
1157   };
1158 
1159  private:
1160   GrowableArray<MoveOperation*> edges;
1161 
1162  public:
1163   ComputeMoveOrder(int total_in_args, VMRegPair* in_regs, int total_c_args, VMRegPair* out_regs,
1164                     BasicType* in_sig_bt, GrowableArray<int>& arg_order, VMRegPair tmp_vmreg) { Unimplemented(); }
1165 
1166   // Collected all the move operations
1167   void add_edge(int src_index, VMRegPair src, int dst_index, VMRegPair dst) { Unimplemented(); }
1168 
1169   // Walk the edges breaking cycles between moves.  The result list
1170   // can be walked in order to produce the proper set of loads
1171   GrowableArray<MoveOperation*>* get_store_order(VMRegPair temp_register) { Unimplemented(); return 0; }
1172 };
1173 
1174 
1175 static void rt_call(MacroAssembler* masm, address dest) {
1176   CodeBlob *cb = CodeCache::find_blob(dest);
1177   if (cb) {
1178     __ far_call(RuntimeAddress(dest), NULL, rscratch2);
1179   } else {
1180     __ lea(rscratch2, RuntimeAddress(dest));
1181     __ bl(rscratch2);
1182     __ maybe_isb();
1183   }
1184 }
1185 
1186 static void verify_oop_args(MacroAssembler* masm,
1187                             methodHandle method,
1188                             const BasicType* sig_bt,
1189                             const VMRegPair* regs) {
1190   Register temp_reg = rscratch2;  // not part of any compiled calling seq
1191   if (VerifyOops) {
1192     for (int i = 0; i < method->size_of_parameters(); i++) {
1193       if (sig_bt[i] == T_OBJECT ||
1194           sig_bt[i] == T_ARRAY) {
1195         VMReg r = regs[i].first();
1196         assert(r->is_valid(), "bad oop arg");
1197         if (r->is_stack()) {
1198           __ ldr(temp_reg, Address(sp, r->reg2stack() * VMRegImpl::stack_slot_size));
1199           __ verify_oop(temp_reg);
1200         } else {
1201           __ verify_oop(r->as_Register());
1202         }
1203       }
1204     }
1205   }
1206 }
1207 
1208 static void gen_special_dispatch(MacroAssembler* masm,
1209                                  methodHandle method,
1210                                  const BasicType* sig_bt,
1211                                  const VMRegPair* regs) {
1212   verify_oop_args(masm, method, sig_bt, regs);
1213   vmIntrinsics::ID iid = method->intrinsic_id();
1214 
1215   // Now write the args into the outgoing interpreter space
1216   bool     has_receiver   = false;
1217   Register receiver_reg   = noreg;
1218   int      member_arg_pos = -1;
1219   Register member_reg     = noreg;
1220   int      ref_kind       = MethodHandles::signature_polymorphic_intrinsic_ref_kind(iid);
1221   if (ref_kind != 0) {
1222     member_arg_pos = method->size_of_parameters() - 1;  // trailing MemberName argument
1223     member_reg = r4;
1224     has_receiver = MethodHandles::ref_kind_has_receiver(ref_kind);
1225   } else if (iid == vmIntrinsics::_invokeBasic) {
1226     has_receiver = true;
1227   } else {
1228     fatal(err_msg_res("unexpected intrinsic id %d", iid));
1229   }
1230 
1231   if (member_reg != noreg) {
1232     // Load the member_arg into register, if necessary.
1233     SharedRuntime::check_member_name_argument_is_last_argument(method, sig_bt, regs);
1234     VMReg r = regs[member_arg_pos].first();
1235     if (r->is_stack()) {
1236       __ ldr(member_reg, Address(sp, r->reg2stack() * VMRegImpl::stack_slot_size));
1237     } else {
1238       // no data motion is needed
1239       member_reg = r->as_Register();
1240     }
1241   }
1242 
1243   if (has_receiver) {
1244     // Make sure the receiver is loaded into a register.
1245     assert(method->size_of_parameters() > 0, "oob");
1246     assert(sig_bt[0] == T_OBJECT, "receiver argument must be an object");
1247     VMReg r = regs[0].first();
1248     assert(r->is_valid(), "bad receiver arg");
1249     if (r->is_stack()) {
1250       // Porting note:  This assumes that compiled calling conventions always
1251       // pass the receiver oop in a register.  If this is not true on some
1252       // platform, pick a temp and load the receiver from stack.
1253       fatal("receiver always in a register");
1254     } else {
1255       // no data motion is needed
1256       receiver_reg = r->as_Register();
1257     }
1258   }
1259 
1260   // Figure out which address we are really jumping to:
1261   MethodHandles::generate_method_handle_dispatch(masm, iid,
1262                                                  receiver_reg, member_reg, /*for_compiler_entry:*/ true);
1263 }
1264 
1265 // ---------------------------------------------------------------------------
1266 // Generate a native wrapper for a given method.  The method takes arguments
1267 // in the Java compiled code convention, marshals them to the native
1268 // convention (handlizes oops, etc), transitions to native, makes the call,
1269 // returns to java state (possibly blocking), unhandlizes any result and
1270 // returns.
1271 //
1272 // Critical native functions are a shorthand for the use of
1273 // GetPrimtiveArrayCritical and disallow the use of any other JNI
1274 // functions.  The wrapper is expected to unpack the arguments before
1275 // passing them to the callee and perform checks before and after the
1276 // native call to ensure that they GC_locker
1277 // lock_critical/unlock_critical semantics are followed.  Some other
1278 // parts of JNI setup are skipped like the tear down of the JNI handle
1279 // block and the check for pending exceptions it's impossible for them
1280 // to be thrown.
1281 //
1282 // They are roughly structured like this:
1283 //    if (GC_locker::needs_gc())
1284 //      SharedRuntime::block_for_jni_critical();
1285 //    tranistion to thread_in_native
1286 //    unpack arrray arguments and call native entry point
1287 //    check for safepoint in progress
1288 //    check if any thread suspend flags are set
1289 //      call into JVM and possible unlock the JNI critical
1290 //      if a GC was suppressed while in the critical native.
1291 //    transition back to thread_in_Java
1292 //    return to caller
1293 //
1294 nmethod* SharedRuntime::generate_native_wrapper(MacroAssembler* masm,
1295                                                 methodHandle method,
1296                                                 int compile_id,
1297                                                 BasicType* in_sig_bt,
1298                                                 VMRegPair* in_regs,
1299                                                 BasicType ret_type) {
1300   if (method->is_method_handle_intrinsic()) {
1301     vmIntrinsics::ID iid = method->intrinsic_id();
1302     intptr_t start = (intptr_t)__ pc();
1303     int vep_offset = ((intptr_t)__ pc()) - start;
1304 
1305     // First instruction must be a nop as it may need to be patched on deoptimisation
1306     __ nop();
1307     gen_special_dispatch(masm,
1308                          method,
1309                          in_sig_bt,
1310                          in_regs);
1311     int frame_complete = ((intptr_t)__ pc()) - start;  // not complete, period
1312     __ flush();
1313     int stack_slots = SharedRuntime::out_preserve_stack_slots();  // no out slots at all, actually
1314     return nmethod::new_native_nmethod(method,
1315                                        compile_id,
1316                                        masm->code(),
1317                                        vep_offset,
1318                                        frame_complete,
1319                                        stack_slots / VMRegImpl::slots_per_word,
1320                                        in_ByteSize(-1),
1321                                        in_ByteSize(-1),
1322                                        (OopMapSet*)NULL);
1323   }
1324 
1325   bool is_critical_native = true;
1326   address native_func = method->critical_native_function();
1327   if (native_func == NULL) {
1328     native_func = method->native_function();
1329     is_critical_native = false;
1330   }
1331   assert(native_func != NULL, "must have function");
1332 
1333   // An OopMap for lock (and class if static)
1334   OopMapSet *oop_maps = new OopMapSet();
1335   intptr_t start = (intptr_t)__ pc();
1336 
1337   // We have received a description of where all the java arg are located
1338   // on entry to the wrapper. We need to convert these args to where
1339   // the jni function will expect them. To figure out where they go
1340   // we convert the java signature to a C signature by inserting
1341   // the hidden arguments as arg[0] and possibly arg[1] (static method)
1342 
1343   const int total_in_args = method->size_of_parameters();
1344   int total_c_args = total_in_args;
1345   if (!is_critical_native) {
1346     total_c_args += 1;
1347     if (method->is_static()) {
1348       total_c_args++;
1349     }
1350   } else {
1351     for (int i = 0; i < total_in_args; i++) {
1352       if (in_sig_bt[i] == T_ARRAY) {
1353         total_c_args++;
1354       }
1355     }
1356   }
1357 
1358   BasicType* out_sig_bt = NEW_RESOURCE_ARRAY(BasicType, total_c_args);
1359   VMRegPair* out_regs   = NEW_RESOURCE_ARRAY(VMRegPair, total_c_args);
1360   BasicType* in_elem_bt = NULL;
1361 
1362   int argc = 0;
1363   if (!is_critical_native) {
1364     out_sig_bt[argc++] = T_ADDRESS;
1365     if (method->is_static()) {
1366       out_sig_bt[argc++] = T_OBJECT;
1367     }
1368 
1369     for (int i = 0; i < total_in_args ; i++ ) {
1370       out_sig_bt[argc++] = in_sig_bt[i];
1371     }
1372   } else {
1373     Thread* THREAD = Thread::current();
1374     in_elem_bt = NEW_RESOURCE_ARRAY(BasicType, total_in_args);
1375     SignatureStream ss(method->signature());
1376     for (int i = 0; i < total_in_args ; i++ ) {
1377       if (in_sig_bt[i] == T_ARRAY) {
1378         // Arrays are passed as int, elem* pair
1379         out_sig_bt[argc++] = T_INT;
1380         out_sig_bt[argc++] = T_ADDRESS;
1381         Symbol* atype = ss.as_symbol(CHECK_NULL);
1382         const char* at = atype->as_C_string();
1383         if (strlen(at) == 2) {
1384           assert(at[0] == '[', "must be");
1385           switch (at[1]) {
1386             case 'B': in_elem_bt[i]  = T_BYTE; break;
1387             case 'C': in_elem_bt[i]  = T_CHAR; break;
1388             case 'D': in_elem_bt[i]  = T_DOUBLE; break;
1389             case 'F': in_elem_bt[i]  = T_FLOAT; break;
1390             case 'I': in_elem_bt[i]  = T_INT; break;
1391             case 'J': in_elem_bt[i]  = T_LONG; break;
1392             case 'S': in_elem_bt[i]  = T_SHORT; break;
1393             case 'Z': in_elem_bt[i]  = T_BOOLEAN; break;
1394             default: ShouldNotReachHere();
1395           }
1396         }
1397       } else {
1398         out_sig_bt[argc++] = in_sig_bt[i];
1399         in_elem_bt[i] = T_VOID;
1400       }
1401       if (in_sig_bt[i] != T_VOID) {
1402         assert(in_sig_bt[i] == ss.type(), "must match");
1403         ss.next();
1404       }
1405     }
1406   }
1407 
1408   // Now figure out where the args must be stored and how much stack space
1409   // they require.
1410   int out_arg_slots;
1411   out_arg_slots = c_calling_convention(out_sig_bt, out_regs, NULL, total_c_args);
1412 
1413   // Compute framesize for the wrapper.  We need to handlize all oops in
1414   // incoming registers
1415 
1416   // Calculate the total number of stack slots we will need.
1417 
1418   // First count the abi requirement plus all of the outgoing args
1419   int stack_slots = SharedRuntime::out_preserve_stack_slots() + out_arg_slots;
1420 
1421   // Now the space for the inbound oop handle area
1422   int total_save_slots = -1;
1423   if (is_critical_native) {
1424     // Critical natives may have to call out so they need a save area
1425     // for register arguments.
1426     int double_slots = 0;
1427     int single_slots = 0;
1428     for ( int i = 0; i < total_in_args; i++) {
1429       if (in_regs[i].first()->is_Register()) {
1430         const Register reg = in_regs[i].first()->as_Register();
1431         switch (in_sig_bt[i]) {
1432           case T_ARRAY:  // critical array (uses 2 slots on LP64)
1433           case T_BOOLEAN:
1434           case T_BYTE:
1435           case T_SHORT:
1436           case T_CHAR:
1437           case T_INT:  single_slots++; break;
1438           case T_LONG: double_slots++; break;
1439           default:  ShouldNotReachHere();
1440         }
1441       } else if (in_regs[i].first()->is_FloatRegister()) {
1442         ShouldNotReachHere();
1443       }
1444     }
1445     total_save_slots = double_slots * 2 + single_slots;
1446     // align the save area
1447     if (double_slots != 0) {
1448       stack_slots = round_to(stack_slots, 2);
1449     }
1450   } else {
1451     total_save_slots = 4 * VMRegImpl::slots_per_word;  // 4 arguments passed in registers
1452   }
1453   assert(total_save_slots != -1, "initialize total_save_slots!");
1454 
1455   int oop_handle_offset = stack_slots;
1456   stack_slots += total_save_slots;
1457 
1458   // Now any space we need for handlizing a klass if static method
1459 
1460   int klass_slot_offset = 0;
1461   int klass_offset = -1;
1462   int lock_slot_offset = 0;
1463   bool is_static = false;
1464 
1465   if (method->is_static()) {
1466     klass_slot_offset = stack_slots;
1467     stack_slots += VMRegImpl::slots_per_word;
1468     klass_offset = klass_slot_offset * VMRegImpl::stack_slot_size;
1469     is_static = true;
1470   }
1471 
1472   // Plus a lock if needed
1473 
1474   if (method->is_synchronized()) {
1475     lock_slot_offset = stack_slots;
1476     stack_slots += VMRegImpl::slots_per_word;
1477   }
1478 
1479   // Now a place (+2) to save return values or temp during shuffling
1480   // + 2 for return address (which we own) and saved rfp
1481   stack_slots += 4;
1482 
1483   // Ok The space we have allocated will look like:
1484   //
1485   //
1486   // FP-> | saved lr            |
1487   //      |---------------------|
1488   //      | saved fp            |
1489   //      |---------------------|
1490   //      | 2 slots for moves   |
1491   //      |---------------------|
1492   //      | lock box (if sync)  |
1493   //      |---------------------| <- lock_slot_offset
1494   //      | klass (if static)   |
1495   //      |---------------------| <- klass_slot_offset
1496   //      | oopHandle area      |
1497   //      |---------------------| <- oop_handle_offset (8 java arg registers)
1498   //      | outbound memory     |
1499   //      | based arguments     |
1500   //      |                     |
1501   //      |---------------------|
1502   //      |                     |
1503   // SP-> | out_preserved_slots |
1504   //
1505   //
1506 
1507 
1508   // Now compute actual number of stack words we need rounding to make
1509   // stack properly aligned.
1510   stack_slots = round_to(stack_slots, StackAlignmentInSlots);
1511 
1512   int stack_size = stack_slots * VMRegImpl::stack_slot_size;
1513 
1514   // First thing make an ic check to see if we should even be here
1515 
1516   // We are free to use all registers as temps without saving them and
1517   // restoring them except rfp. rfp is the only callee save register
1518   // as far as the interpreter and the compiler(s) are concerned.
1519 
1520 
1521   const Register ic_reg = rscratch2;
1522   const Register receiver = j_rarg0;
1523 
1524   Label hit;
1525   Label exception_pending;
1526 
1527   assert_different_registers(ic_reg, receiver, rscratch1);
1528   __ verify_oop(receiver);
1529   __ cmp_klass(receiver, ic_reg, rscratch1);
1530   __ b(hit, Assembler::EQ);
1531 
1532   __ far_jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
1533 
1534   // Verified entry point must be aligned
1535   __ align(8);
1536 
1537   __ bind(hit);
1538 
1539 #ifdef ASSERT
1540   __ mov(ic_reg, 0xdead); // trash ic_reg(rscratch2), as used as real scratch further
1541 #endif
1542 
1543   int vep_offset = ((intptr_t)__ pc()) - start;
1544 
1545   // Generate stack overflow check
1546 
1547   // If we have to make this method not-entrant we'll overwrite its
1548   // first instruction with a jump.  For this action to be legal we
1549   // must ensure that this first instruction is a B, BL, NOP, BKPT,
1550   // SVC, HVC, or SMC.  Make it a NOP.
1551   __ nop();
1552 
1553   if (UseStackBanging) {
1554     __ bang_stack_with_offset(StackShadowPages*os::vm_page_size());
1555   } else {
1556     Unimplemented();
1557   }
1558 
1559   // Generate a new frame for the wrapper.
1560   __ enter();
1561   // -2 because return address is already present and so is saved rfp
1562   __ sub(sp, sp, stack_size - 2*wordSize);
1563 
1564   // Frame is now completed as far as size and linkage.
1565   int frame_complete = ((intptr_t)__ pc()) - start;
1566 
1567   if (is_critical_native) {
1568     check_needs_gc_for_critical_native(masm, stack_slots, total_c_args, total_in_args,
1569                                        oop_handle_offset, oop_maps, in_regs, in_sig_bt);
1570   }
1571 
1572   //
1573   // We immediately shuffle the arguments so that any vm call we have to
1574   // make from here on out (sync slow path, jvmti, etc.) we will have
1575   // captured the oops from our caller and have a valid oopMap for
1576   // them.
1577 
1578   // -----------------
1579   // The Grand Shuffle
1580 
1581   // The Java calling convention is either equal (linux) or denser (win64) than the
1582   // c calling convention. However the because of the jni_env argument the c calling
1583   // convention always has at least one more (and two for static) arguments than Java.
1584   // Therefore if we move the args from java -> c backwards then we will never have
1585   // a register->register conflict and we don't have to build a dependency graph
1586   // and figure out how to break any cycles.
1587   //
1588 
1589   // Record sp-based slot for receiver on stack for non-static methods
1590   int receiver_offset = -1;
1591 
1592   // This is a trick. We double the stack slots so we can claim
1593   // the oops in the caller's frame. Since we are sure to have
1594   // more args than the caller doubling is enough to make
1595   // sure we can capture all the incoming oop args from the
1596   // caller.
1597   //
1598   OopMap* map = new OopMap(stack_slots * 2, 0 /* arg_slots*/);
1599 
1600   // Mark location of rfp (someday)
1601   // map->set_callee_saved(VMRegImpl::stack2reg( stack_slots - 2), stack_slots * 2, 0, vmreg(rfp));
1602 
1603 
1604 #ifdef ASSERT
1605   bool reg_destroyed[RegisterImpl::number_of_registers];
1606   bool freg_destroyed[FloatRegisterImpl::number_of_registers];
1607   for ( int r = 0 ; r < RegisterImpl::number_of_registers ; r++ ) {
1608     reg_destroyed[r] = false;
1609   }
1610   for ( int f = 0 ; f < FloatRegisterImpl::number_of_registers ; f++ ) {
1611     freg_destroyed[f] = false;
1612   }
1613 
1614 #endif // ASSERT
1615 
1616   // This may iterate in two different directions depending on the
1617   // kind of native it is.  The reason is that for regular JNI natives
1618   // the incoming and outgoing registers are offset upwards and for
1619   // critical natives they are offset down.
1620   GrowableArray<int> arg_order(2 * total_in_args);
1621   VMRegPair tmp_vmreg;
1622   tmp_vmreg.set1(rscratch2->as_VMReg());
1623 
1624   if (!is_critical_native) {
1625     for (int i = total_in_args - 1, c_arg = total_c_args - 1; i >= 0; i--, c_arg--) {
1626       arg_order.push(i);
1627       arg_order.push(c_arg);
1628     }
1629   } else {
1630     // Compute a valid move order, using tmp_vmreg to break any cycles
1631     ComputeMoveOrder cmo(total_in_args, in_regs, total_c_args, out_regs, in_sig_bt, arg_order, tmp_vmreg);
1632   }
1633 
1634   int temploc = -1;
1635   for (int ai = 0; ai < arg_order.length(); ai += 2) {
1636     int i = arg_order.at(ai);
1637     int c_arg = arg_order.at(ai + 1);
1638     __ block_comment(err_msg("move %d -> %d", i, c_arg));
1639     if (c_arg == -1) {
1640       assert(is_critical_native, "should only be required for critical natives");
1641       // This arg needs to be moved to a temporary
1642       __ mov(tmp_vmreg.first()->as_Register(), in_regs[i].first()->as_Register());
1643       in_regs[i] = tmp_vmreg;
1644       temploc = i;
1645       continue;
1646     } else if (i == -1) {
1647       assert(is_critical_native, "should only be required for critical natives");
1648       // Read from the temporary location
1649       assert(temploc != -1, "must be valid");
1650       i = temploc;
1651       temploc = -1;
1652     }
1653 #ifdef ASSERT
1654     if (in_regs[i].first()->is_Register()) {
1655       assert(!reg_destroyed[in_regs[i].first()->as_Register()->encoding()], "destroyed reg!");
1656     } else if (in_regs[i].first()->is_FloatRegister()) {
1657       assert(!freg_destroyed[in_regs[i].first()->as_FloatRegister()->encoding()], "destroyed reg!");
1658     }
1659     if (out_regs[c_arg].first()->is_Register()) {
1660       reg_destroyed[out_regs[c_arg].first()->as_Register()->encoding()] = true;
1661     } else if (out_regs[c_arg].first()->is_FloatRegister()) {
1662       freg_destroyed[out_regs[c_arg].first()->as_FloatRegister()->encoding()] = true;
1663     }
1664 #endif // ASSERT
1665     switch (in_sig_bt[i]) {
1666       case T_ARRAY:
1667         if (is_critical_native) {
1668           unpack_array_argument(masm, in_regs[i], in_elem_bt[i], out_regs[c_arg + 1], out_regs[c_arg]);
1669           c_arg++;
1670 #ifdef ASSERT
1671           if (out_regs[c_arg].first()->is_Register()) {
1672             reg_destroyed[out_regs[c_arg].first()->as_Register()->encoding()] = true;
1673           } else if (out_regs[c_arg].first()->is_FloatRegister()) {
1674             freg_destroyed[out_regs[c_arg].first()->as_FloatRegister()->encoding()] = true;
1675           }
1676 #endif
1677           break;
1678         }
1679       case T_OBJECT:
1680         assert(!is_critical_native, "no oop arguments");
1681         object_move(masm, map, oop_handle_offset, stack_slots, in_regs[i], out_regs[c_arg],
1682                     ((i == 0) && (!is_static)),
1683                     &receiver_offset);
1684         break;
1685       case T_VOID:
1686         break;
1687 
1688       case T_FLOAT:
1689         float_move(masm, in_regs[i], out_regs[c_arg]);
1690         break;
1691 
1692       case T_DOUBLE:
1693         assert( i + 1 < total_in_args &&
1694                 in_sig_bt[i + 1] == T_VOID &&
1695                 out_sig_bt[c_arg+1] == T_VOID, "bad arg list");
1696         double_move(masm, in_regs[i], out_regs[c_arg]);
1697         break;
1698 
1699       case T_LONG :
1700         long_move(masm, in_regs[i], out_regs[c_arg]);
1701         break;
1702 
1703       case T_BOOLEAN :
1704       case T_BYTE :
1705       case T_CHAR :
1706       case T_SHORT :
1707       case T_INT :
1708         move_int(masm, in_regs[i], out_regs[c_arg]);
1709     break;
1710 
1711       case T_ADDRESS: assert(false, "found T_ADDRESS in java args");
1712       case T_NARROWOOP :
1713       case T_METADATA :
1714       case T_NARROWKLASS :
1715       default:
1716     ShouldNotReachHere();
1717     }
1718   }
1719 
1720   // point c_arg at the first arg that is already loaded in case we
1721   // need to spill before we call out
1722   int c_arg = total_c_args - total_in_args;
1723 
1724   // We use r4 as the oop handle for the receiver/klass
1725   // It is callee save so it survives the call to native
1726 
1727   const Register oop_handle_reg = r4;
1728 
1729   // Pre-load a static method's oop.  Used both by locking code and
1730   // the normal JNI call code.
1731   if (method->is_static() && !is_critical_native) {
1732 
1733     //  load oop into a register
1734     __ movoop(oop_handle_reg,
1735               JNIHandles::make_local(method->method_holder()->java_mirror()),
1736               /*immediate*/true);
1737 
1738     // Now handlize the static class mirror it's known not-null.
1739     __ str(oop_handle_reg, Address(sp, klass_offset));
1740     map->set_oop(VMRegImpl::stack2reg(klass_slot_offset));
1741 
1742     // Now get the handle
1743     __ lea(oop_handle_reg, Address(sp, klass_offset));
1744     // store the klass handle as second argument
1745     __ mov(c_rarg1, oop_handle_reg);
1746     // and protect the arg if we must spill
1747     c_arg--;
1748   }
1749 
1750   // Change state to native (we save the return address in the thread, since it might not
1751   // be pushed on the stack when we do a a stack traversal). It is enough that the pc()
1752   // points into the right code segment. It does not have to be the correct return pc.
1753   // We use the same pc/oopMap repeatedly when we call out
1754 
1755   intptr_t the_pc = (intptr_t) __ pc();
1756   oop_maps->add_gc_map(the_pc - start, map);
1757 
1758   __ set_last_Java_frame(sp, noreg, (address)the_pc, rscratch1);
1759 
1760 
1761   // We have all of the arguments setup at this point. We must not touch any register
1762   // argument registers at this point (what if we save/restore them there are no oop?
1763 
1764 #ifdef DTRACE_ENABLED
1765   {
1766     SkipIfEqual skip(masm, &DTraceMethodProbes, false);
1767     // protect the args we've loaded
1768     save_args(masm, total_c_args, c_arg, out_regs);
1769     __ mov_metadata(c_rarg1, method());
1770     __ call_VM_leaf(
1771       CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_entry),
1772       rthread, c_rarg1);
1773     restore_args(masm, total_c_args, c_arg, out_regs);
1774   }
1775 #endif
1776 
1777   // RedefineClasses() tracing support for obsolete method entry
1778   if (RC_TRACE_IN_RANGE(0x00001000, 0x00002000)) {
1779     // protect the args we've loaded
1780     save_args(masm, total_c_args, c_arg, out_regs);
1781     __ mov_metadata(c_rarg1, method());
1782     __ call_VM_leaf(
1783       CAST_FROM_FN_PTR(address, SharedRuntime::rc_trace_method_entry),
1784       rthread, c_rarg1);
1785     restore_args(masm, total_c_args, c_arg, out_regs);
1786   }
1787 
1788   // Lock a synchronized method
1789 
1790   // Register definitions used by locking and unlocking
1791 
1792   Label slow_path_lock;
1793   Label lock_done;
1794 
1795   if (method->is_synchronized()) {
1796     assert(!is_critical_native, "unhandled");
1797     // TODO Fast path disabled as requires at least 4 registers, which already contain arguments prepared for call
1798 
1799     // Get the handle (the 2nd argument)
1800     __ mov(oop_handle_reg, c_rarg1);
1801     __ b(slow_path_lock);
1802 
1803     // Slow path will re-enter here
1804     __ bind(lock_done);
1805   }
1806 
1807 
1808   // Finally just about ready to make the JNI call
1809 
1810 
1811   // get JNIEnv* which is first argument to native
1812   if (!is_critical_native) {
1813     __ lea(c_rarg0, Address(rthread, in_bytes(JavaThread::jni_environment_offset())));
1814   }
1815 
1816   // Now set thread in native
1817   __ mov(rscratch1, _thread_in_native);
1818   __ lea(rscratch2, Address(rthread, JavaThread::thread_state_offset()));
1819   __ dmb(Assembler::ISH);
1820   __ str(rscratch1, rscratch2);
1821 
1822   // Do the call
1823   rt_call(masm, native_func);
1824 
1825   // Unpack native results.
1826   switch (ret_type) {
1827   case T_BOOLEAN: __ uxtb(r0, r0);           break;
1828   case T_CHAR   : __ uxth(r0, r0);           break;
1829   case T_BYTE   : __ sxtb(r0, r0);           break;
1830   case T_SHORT  : __ sxth(r0, r0);           break;
1831   case T_INT    :                                    break;
1832   case T_DOUBLE :
1833   case T_FLOAT  :
1834     // Result is in d0 we'll save as needed
1835     break;
1836   case T_ARRAY:                 // Really a handle
1837   case T_OBJECT:                // Really a handle
1838       break; // can't de-handlize until after safepoint check
1839   case T_VOID: break;
1840   case T_LONG: break;
1841   default       : ShouldNotReachHere();
1842   }
1843 
1844   // Switch thread to "native transition" state before reading the synchronization state.
1845   // This additional state is necessary because reading and testing the synchronization
1846   // state is not atomic w.r.t. GC, as this scenario demonstrates:
1847   //     Java thread A, in _thread_in_native state, loads _not_synchronized and is preempted.
1848   //     VM thread changes sync state to synchronizing and suspends threads for GC.
1849   //     Thread A is resumed to finish this native method, but doesn't block here since it
1850   //     didn't see any synchronization is progress, and escapes.
1851   __ mov(rscratch1, _thread_in_native_trans);
1852   __ lea(rscratch2, Address(rthread, JavaThread::thread_state_offset()));
1853   __ dmb(Assembler::ISH);
1854   __ str(rscratch1, rscratch2);
1855 
1856   if(os::is_MP()) {
1857     if (UseMembar) {
1858       // Force this write out before the read below
1859       __ dmb(Assembler::SY);
1860     } else {
1861       // Write serialization page so VM thread can do a pseudo remote membar.
1862       // We use the current thread pointer to calculate a thread specific
1863       // offset to write to within the page. This minimizes bus traffic
1864       // due to cache line collision.
1865       __ serialize_memory(rthread, rscratch1);
1866     }
1867   }
1868 
1869   Label after_transition;
1870 
1871   // check for safepoint operation in progress and/or pending suspend requests
1872   {
1873     Label Continue;
1874 
1875     __ mov(rscratch1, ExternalAddress((address)SafepointSynchronize::address_of_state()));
1876     __ ldr(rscratch1, Address(rscratch1));
1877     __ cmp(rscratch1, SafepointSynchronize::_not_synchronized);
1878 
1879     Label L;
1880     __ b(L, Assembler::NE);
1881     __ ldr(rscratch1, Address(rthread, JavaThread::suspend_flags_offset()));
1882     __ cbz(rscratch1, Continue);
1883     __ bind(L);
1884 
1885     // Don't use call_VM as it will see a possible pending exception and forward it
1886     // and never return here preventing us from clearing _last_native_pc down below.
1887     //
1888     save_native_result(masm, ret_type, stack_slots);
1889     __ mov(c_rarg0, rthread);
1890 #ifndef PRODUCT
1891   assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
1892 #endif
1893     if (!is_critical_native) {
1894       __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans)));
1895     } else {
1896       __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans_and_transition)));
1897     }
1898     __ bl(rscratch1);
1899     __ maybe_isb();
1900     // Restore any method result value
1901     restore_native_result(masm, ret_type, stack_slots);
1902 
1903     if (is_critical_native) {
1904       // The call above performed the transition to thread_in_Java so
1905       // skip the transition logic below.
1906       __ b(after_transition);
1907     }
1908 
1909     __ bind(Continue);
1910   }
1911 
1912   // change thread state
1913   __ mov(rscratch1, _thread_in_Java);
1914   __ lea(rscratch2, Address(rthread, JavaThread::thread_state_offset()));
1915   __ dmb(Assembler::ISH);
1916   __ str(rscratch1, rscratch2);
1917   __ bind(after_transition);
1918 
1919   Label reguard;
1920   Label reguard_done;
1921   __ ldrb(rscratch1, Address(rthread, JavaThread::stack_guard_state_offset()));
1922   __ cmp(rscratch1, JavaThread::stack_guard_yellow_disabled);
1923   __ b(reguard, Assembler::EQ);
1924   __ bind(reguard_done);
1925 
1926   // native result if any is live
1927 
1928   // Unlock
1929   Label unlock_done;
1930   Label slow_path_unlock;
1931   if (method->is_synchronized()) {
1932     // TODO fast path disabled as requires at least 4 registers, but r0,r1 contains result
1933     __ b(slow_path_unlock);
1934 
1935     // slow path re-enters here
1936     __ bind(unlock_done);
1937   }
1938 
1939 #ifdef DTRACE_ENABLED
1940   {
1941     SkipIfEqual skip(masm, &DTraceMethodProbes, false);
1942     save_native_result(masm, ret_type, stack_slots);
1943     __ mov_metadata(c_rarg1, method());
1944     __ call_VM_leaf(
1945          CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_exit),
1946          rthread, c_rarg1);
1947     restore_native_result(masm, ret_type, stack_slots);
1948   }
1949 #endif
1950 
1951   __ reset_last_Java_frame(false, true);
1952 
1953   // Unpack oop result
1954   if (ret_type == T_OBJECT || ret_type == T_ARRAY) {
1955       Label L;
1956       __ cbz(r0, L);
1957       __ ldr(r0, Address(r0, 0));
1958       __ bind(L);
1959       __ verify_oop(r0);
1960   }
1961 
1962   if (!is_critical_native) {
1963     // reset handle block
1964     __ mov(rscratch1, 0);
1965     __ ldr(r2, Address(rthread, JavaThread::active_handles_offset()));
1966     __ str(rscratch1, Address(r2, JNIHandleBlock::top_offset_in_bytes()));
1967   }
1968 
1969   __ leave();
1970 
1971   if (!is_critical_native) {
1972     // Any exception pending?
1973     __ ldr(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
1974     __ cbnz(rscratch1, exception_pending);
1975   }
1976 
1977   // We're done
1978   __ b(lr);
1979 
1980   // Unexpected paths are out of line and go here
1981 
1982   if (!is_critical_native) {
1983     // forward the exception
1984     __ bind(exception_pending);
1985 
1986     // and forward the exception
1987     __ far_jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
1988   }
1989 
1990   // Slow path locking & unlocking
1991   if (method->is_synchronized()) {
1992 
1993     // BEGIN Slow path lock
1994     __ bind(slow_path_lock);
1995 
1996     // has last_Java_frame setup. No exceptions so do vanilla call not call_VM
1997     // args are (oop obj, BasicLock* lock, JavaThread* thread)
1998 
1999     // protect the args we've loaded
2000     save_args(masm, total_c_args, c_arg, out_regs);
2001 
2002     __ ldr(c_rarg0, Address(oop_handle_reg));
2003     __ lea(c_rarg1, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
2004     __ mov(c_rarg2, rthread);
2005 
2006     // Not a leaf but we have last_Java_frame setup as we want
2007     __ call_VM_leaf(CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_locking_C), 3);
2008     restore_args(masm, total_c_args, c_arg, out_regs);
2009 
2010 #ifdef ASSERT
2011     { Label L;
2012       __ ldr(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
2013       __ cbz(rscratch1, L);
2014       __ stop("no pending exception allowed on exit from monitorenter");
2015       __ bind(L);
2016     }
2017 #endif
2018     __ b(lock_done);
2019 
2020     // END Slow path lock
2021 
2022     // BEGIN Slow path unlock
2023     __ bind(slow_path_unlock);
2024 
2025     // If we haven't already saved the native result we must save it now as xmm registers
2026     // are still exposed.
2027 
2028     save_native_result(masm, ret_type, stack_slots);
2029 
2030     __ ldr(c_rarg0, Address(oop_handle_reg));
2031     __ lea(c_rarg1, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
2032 
2033     // Save pending exception around call to VM (which contains an EXCEPTION_MARK)
2034     __ ldr(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
2035     __ mov(rscratch2, 0);
2036     __ str(rscratch2, Address(rthread, in_bytes(Thread::pending_exception_offset())));
2037 
2038     rt_call(masm, CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C));
2039 
2040 #ifdef ASSERT
2041     {
2042       Label L;
2043       __ ldr(rscratch2, Address(rthread, in_bytes(Thread::pending_exception_offset())));
2044       __ cbz(rscratch2, L);
2045       __ stop("no pending exception allowed on exit complete_monitor_unlocking_C");
2046       __ bind(L);
2047     }
2048 #endif // ASSERT
2049 
2050     __ str(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
2051 
2052     restore_native_result(masm, ret_type, stack_slots);
2053 
2054     __ b(unlock_done);
2055 
2056     // END Slow path unlock
2057 
2058   } // synchronized
2059 
2060   // SLOW PATH Reguard the stack if needed
2061 
2062   __ bind(reguard);
2063   save_native_result(masm, ret_type, stack_slots);
2064   rt_call(masm, CAST_FROM_FN_PTR(address, SharedRuntime::reguard_yellow_pages));
2065   restore_native_result(masm, ret_type, stack_slots);
2066   // and continue
2067   __ b(reguard_done);
2068 
2069 
2070 
2071   __ flush();
2072 
2073   nmethod *nm = nmethod::new_native_nmethod(method,
2074                                             compile_id,
2075                                             masm->code(),
2076                                             vep_offset,
2077                                             frame_complete,
2078                                             stack_slots / VMRegImpl::slots_per_word,
2079                                             (is_static ? in_ByteSize(klass_offset) : in_ByteSize(receiver_offset)),
2080                                             in_ByteSize(lock_slot_offset*VMRegImpl::stack_slot_size),
2081                                             oop_maps);
2082 
2083   if (is_critical_native) {
2084     nm->set_lazy_critical_native(true);
2085   }
2086 
2087   return nm;
2088 }
2089 
2090 // this function returns the adjust size (in number of words) to a c2i adapter
2091 // activation for use during deoptimization
2092 int Deoptimization::last_frame_adjust(int callee_parameters, int callee_locals) {
2093   assert(callee_locals >= callee_parameters,
2094           "test and remove; got more parms than locals");
2095   if (callee_locals < callee_parameters)
2096     return 0;                   // No adjustment for negative locals
2097   int diff = (callee_locals - callee_parameters) * Interpreter::stackElementWords;
2098   // diff is counted in stack words
2099   return round_to(diff, 2);
2100 }
2101 
2102 
2103 //------------------------------generate_deopt_blob----------------------------
2104 void SharedRuntime::generate_deopt_blob() {
2105 
2106   // Allocate space for the code
2107   ResourceMark rm;
2108   // Setup code generation tools
2109   CodeBuffer buffer("deopt_blob", 2048, 1024);
2110   MacroAssembler* masm = new MacroAssembler(&buffer);
2111   int frame_size_in_words;
2112   OopMap* map = NULL;
2113   OopMapSet *oop_maps = new OopMapSet();
2114 
2115   // -------------
2116   // This code enters when returning to a de-optimized nmethod.  A return
2117   // address has been pushed on the the stack, and return values are in
2118   // registers.
2119   // If we are doing a normal deopt then we were called from the patched
2120   // nmethod from the point we returned to the nmethod. So the return
2121   // address on the stack is wrong by NativeCall::instruction_size
2122   // We will adjust the value so it looks like we have the original return
2123   // address on the stack (like when we eagerly deoptimized).
2124   // In the case of an exception pending when deoptimizing, we enter
2125   // with a return address on the stack that points after the call we patched
2126   // into the exception handler. We have the following register state from,
2127   // e.g., the forward exception stub (see stubGenerator_x86_64.cpp).
2128   //    r0: exception oop
2129   //    r7: exception handler
2130   //    r3: throwing pc
2131   // So in this case we simply jam r3 into the useless return address and
2132   // the stack looks just like we want.
2133   //
2134   // At this point we need to de-opt.  We save the argument return
2135   // registers.  We call the first C routine, fetch_unroll_info().  This
2136   // routine captures the return values and returns a structure which
2137   // describes the current frame size and the sizes of all replacement frames.
2138   // The current frame is compiled code and may contain many inlined
2139   // functions, each with their own JVM state.  We pop the current frame, then
2140   // push all the new frames.  Then we call the C routine unpack_frames() to
2141   // populate these frames.  Finally unpack_frames() returns us the new target
2142   // address.  Notice that callee-save registers are BLOWN here; they have
2143   // already been captured in the vframeArray at the time the return PC was
2144   // patched.
2145   address start = __ pc();
2146   Label cont;
2147 
2148   // Prolog for non exception case!
2149 
2150   // Save everything in sight.
2151   map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
2152 
2153   // Normal deoptimization.  Save exec mode for unpack_frames.
2154   __ mov(r7, Deoptimization::Unpack_deopt); // callee-saved
2155   __ b(cont);
2156 
2157   int reexecute_offset = __ pc() - start;
2158 
2159   // Reexecute case
2160   // return address is the pc describes what bci to do re-execute at
2161 
2162   // No need to update map as each call to save_live_registers will produce identical oopmap
2163   (void) RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
2164 
2165   __ mov(r7, Deoptimization::Unpack_reexecute); // callee-saved
2166   __ b(cont);
2167 
2168   int exception_offset = __ pc() - start;
2169 
2170   // Prolog for exception case
2171 
2172   // all registers are dead at this entry point, except for r0, and
2173   // r3 which contain the exception oop and exception pc
2174   // respectively.  Set them in TLS and fall thru to the
2175   // unpack_with_exception_in_tls entry point.
2176 
2177   __ str(r3, Address(rthread, JavaThread::exception_pc_offset()));
2178   __ str(r0, Address(rthread, JavaThread::exception_oop_offset()));
2179 
2180   int exception_in_tls_offset = __ pc() - start;
2181 
2182   // new implementation because exception oop is now passed in JavaThread
2183 
2184   // Prolog for exception case
2185   // All registers must be preserved because they might be used by LinearScan
2186   // Exceptiop oop and throwing PC are passed in JavaThread
2187   // tos: stack at point of call to method that threw the exception (i.e. only
2188   // args are on the stack, no return address)
2189 
2190   // The return address pushed by save_live_registers will be patched
2191   // later with the throwing pc. The correct value is not available
2192   // now because loading it from memory would destroy registers.
2193 
2194   // NB: The SP at this point must be the SP of the method that is
2195   // being deoptimized.  Deoptimization assumes that the frame created
2196   // here by save_live_registers is immediately below the method's SP.
2197   // This is a somewhat fragile mechanism.
2198 
2199   // Save everything in sight.
2200   map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
2201 
2202   // Now it is safe to overwrite any register
2203 
2204   // Deopt during an exception.  Save exec mode for unpack_frames.
2205   __ mov(r7, Deoptimization::Unpack_exception); // callee-saved
2206 
2207   // load throwing pc from JavaThread and patch it as the return address
2208   // of the current frame. Then clear the field in JavaThread
2209 
2210   __ ldr(r3, Address(rthread, JavaThread::exception_pc_offset()));
2211   __ str(r3, Address(rfp));
2212   __ mov(rscratch1, 0);
2213   __ str(rscratch1, Address(rthread, JavaThread::exception_pc_offset()));
2214 
2215 #ifdef ASSERT
2216   // verify that there is really an exception oop in JavaThread
2217   __ ldr(r0, Address(rthread, JavaThread::exception_oop_offset()));
2218   __ verify_oop(r0);
2219 
2220   // verify that there is no pending exception
2221   Label no_pending_exception;
2222   __ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
2223   __ cbz(rscratch1, no_pending_exception);
2224   __ stop("must not have pending exception here");
2225   __ bind(no_pending_exception);
2226 #endif
2227 
2228   __ bind(cont);
2229 
2230   // Call C code.  Need thread and this frame, but NOT official VM entry
2231   // crud.  We cannot block on this call, no GC can happen.
2232   //
2233   // UnrollBlock* fetch_unroll_info(JavaThread* thread)
2234 
2235   // fetch_unroll_info needs to call last_java_frame().
2236 
2237   Label retaddr;
2238   __ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
2239 #ifdef ASSERT0
2240   { Label L;
2241     __ ldr(rscratch1, Address(rthread,
2242                               JavaThread::last_Java_fp_offset()));
2243     __ cbz(rscratch1, L);
2244     __ stop("SharedRuntime::generate_deopt_blob: last_Java_fp not cleared");
2245     __ bind(L);
2246   }
2247 #endif // ASSERT
2248   __ mov(c_rarg0, rthread);
2249   __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::fetch_unroll_info)));
2250   __ bl(rscratch1);
2251   __ bind(retaddr);
2252 
2253   // Need to have an oopmap that tells fetch_unroll_info where to
2254   // find any register it might need.
2255   oop_maps->add_gc_map(__ pc() - start, map);
2256 
2257   __ reset_last_Java_frame(false, true);
2258 
2259   // Load UnrollBlock* into rdi
2260   __ mov(r5, r0);
2261 
2262    Label noException;
2263   __ cmp(r7, Deoptimization::Unpack_exception);   // Was exception pending?
2264   __ b(noException, Assembler::NE);
2265   __ ldr(r0, Address(rthread, JavaThread::exception_oop_offset()));
2266   // QQQ this is useless it was NULL above
2267   __ ldr(r3, Address(rthread, JavaThread::exception_pc_offset()));
2268   __ mov(rscratch1, 0);
2269   __ str(rscratch1, Address(rthread, JavaThread::exception_oop_offset()));
2270   __ str(rscratch1, Address(rthread, JavaThread::exception_pc_offset()));
2271 
2272   __ verify_oop(r0);
2273 
2274   // Overwrite the result registers with the exception results.
2275   __ str(r0, Address(sp, RegisterSaver::offset_in_bytes(RegisterSaver::r0_off)));
2276   // I think this is useless
2277   // __ str(r3, Address(sp, RegisterSaver::r3_offset_in_bytes()));
2278 
2279   __ bind(noException);
2280 
2281   // Only register save data is on the stack.
2282   // Now restore the result registers.  Everything else is either dead
2283   // or captured in the vframeArray.
2284   RegisterSaver::restore_result_registers(masm);
2285 
2286   // All of the register save area has been popped of the stack. Only the
2287   // return address remains.
2288 
2289   // Pop all the frames we must move/replace.
2290   //
2291   // Frame picture (youngest to oldest)
2292   // 1: self-frame (no frame link)
2293   // 2: deopting frame  (no frame link)
2294   // 3: caller of deopting frame (could be compiled/interpreted).
2295   //
2296   // Note: by leaving the return address of self-frame on the stack
2297   // and using the size of frame 2 to adjust the stack
2298   // when we are done the return to frame 3 will still be on the stack.
2299 
2300   // Pop deoptimized frame
2301   __ ldr(r2, Address(r5, Deoptimization::UnrollBlock::size_of_deoptimized_frame_offset_in_bytes()));
2302   __ sub(r2, r2, 2 * wordSize);
2303   __ add(sp, sp, r2);
2304   __ ldrd(rfp, lr, __ post(sp, 2 * wordSize));
2305   // LR should now be the return address to the caller (3)
2306 
2307 #ifdef ASSERT
2308   // Compilers generate code that bang the stack by as much as the
2309   // interpreter would need. So this stack banging should never
2310   // trigger a fault. Verify that it does not on non product builds.
2311   if (UseStackBanging) {
2312     __ ldr(rscratch2, Address(r5, Deoptimization::UnrollBlock::total_frame_sizes_offset_in_bytes()));
2313     __ bang_stack_size(rscratch2, r2);
2314   }
2315 #endif
2316   // Load address of array of frame pcs into r2
2317   __ ldr(r2, Address(r5, Deoptimization::UnrollBlock::frame_pcs_offset_in_bytes()));
2318 
2319   // Trash the old pc
2320   // __ addptr(sp, wordSize);  FIXME ????
2321 
2322   // Load address of array of frame sizes into r4
2323   __ ldr(r4, Address(r5, Deoptimization::UnrollBlock::frame_sizes_offset_in_bytes()));
2324 
2325   // Load counter into r3
2326   __ ldr(r3, Address(r5, Deoptimization::UnrollBlock::number_of_frames_offset_in_bytes()));
2327 
2328   // Now adjust the caller's stack to make up for the extra locals
2329   // but record the original sp so that we can save it in the skeletal interpreter
2330   // frame and the stack walking of interpreter_sender will get the unextended sp
2331   // value and not the "real" sp value.
2332 
2333   const Register sender_sp = r6;
2334 
2335   __ mov(sender_sp, sp);
2336   __ ldr(rscratch1, Address(r5,
2337                        Deoptimization::UnrollBlock::
2338                        caller_adjustment_offset_in_bytes()));
2339   __ sub(sp, sp, rscratch1);
2340 
2341   // Push interpreter frames in a loop
2342   __ mov(rscratch1, (address)0xDEADDEAD);        // Make a recognizable pattern
2343   // Initially used to place 0xDEADDEAD in rscratch2 as well - why?
2344   __ mov(rscratch2, 0);
2345   Label loop;
2346   __ bind(loop);
2347   __ ldr(rscratch1, Address(__ post(r4, wordSize)));          // Load frame size
2348   __ sub(rscratch1, rscratch1, 2*wordSize);           // We'll push pc and fp by hand
2349   __ ldr(lr, Address(__ post(r2, wordSize)));  // Load pc
2350   __ enter();                           // Save old & set new fp
2351   __ sub(sp, sp, rscratch1);                  // Prolog
2352   // This value is corrected by layout_activation_impl
2353   __ str(rscratch2, Address(rfp, frame::interpreter_frame_last_sp_offset * wordSize));
2354   __ str(sender_sp, Address(rfp, frame::interpreter_frame_sender_sp_offset * wordSize)); // Make it walkable
2355   __ mov(sender_sp, sp);               // Pass sender_sp to next frame
2356   __ sub(r3, r3, 1);                   // Decrement counter
2357   __ cbnz(r3, loop);
2358 
2359     // Re-push self-frame
2360   __ ldr(lr, Address(r2));
2361   __ enter();
2362 
2363   // Allocate a full sized register save area.  We subtract 2 because
2364   // enter() just pushed 2 words
2365   __ sub(sp, sp, (frame_size_in_words - 2) * wordSize);
2366 
2367   // Restore frame locals after moving the frame
2368   __ vstr_f64(d0, Address(sp, RegisterSaver::offset_in_bytes(RegisterSaver::fpu_state_off)));
2369   __ strd(r0, Address(sp, RegisterSaver::offset_in_bytes(RegisterSaver::r0_off)));
2370 
2371   // Call C code.  Need thread but NOT official VM entry
2372   // crud.  We cannot block on this call, no GC can happen.  Call should
2373   // restore return values to their stack-slots with the new SP.
2374   //
2375   // void Deoptimization::unpack_frames(JavaThread* thread, int exec_mode)
2376 
2377   // Use rfp because the frames look interpreted now
2378   // Don't need the precise return PC here, just precise enough to point into this code blob.
2379   address the_pc = __ pc();
2380   __ set_last_Java_frame(sp, rfp, the_pc, rscratch1);
2381 
2382   __ mov(c_rarg0, rthread);
2383   __ mov(c_rarg1, r7); // second arg: exec_mode
2384   __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::unpack_frames)));
2385   __ bl(rscratch1);
2386 
2387   // Set an oopmap for the call site
2388   // Use the same PC we used for the last java frame
2389   oop_maps->add_gc_map(the_pc - start,
2390                        new OopMap( frame_size_in_words, 0 ));
2391 
2392   // Clear fp AND pc
2393   __ reset_last_Java_frame(true, true);
2394 
2395   // Collect return values
2396   __ vldr_f64(d0, Address(sp, RegisterSaver::offset_in_bytes(RegisterSaver::fpu_state_off)));
2397   __ ldrd(r0, Address(sp, RegisterSaver::offset_in_bytes(RegisterSaver::r0_off)));
2398   // I think this is useless (throwing pc?)
2399   // __ ldr(r3, Address(sp, RegisterSaver::r3_offset_in_bytes()));
2400 
2401   // Pop self-frame.
2402   __ leave();                           // Epilog
2403 
2404   // Jump to interpreter
2405   __ b(lr);
2406 
2407   // Make sure all code is generated
2408   masm->flush();
2409 
2410   _deopt_blob = DeoptimizationBlob::create(&buffer, oop_maps, 0, exception_offset, reexecute_offset, frame_size_in_words);
2411   _deopt_blob->set_unpack_with_exception_in_tls_offset(exception_in_tls_offset);
2412 
2413 }
2414 
2415 uint SharedRuntime::out_preserve_stack_slots() {
2416   return 0;
2417 }
2418 
2419 #ifdef COMPILER2
2420 //------------------------------generate_uncommon_trap_blob--------------------
2421 /*void SharedRuntime::generate_uncommon_trap_blob() {
2422   // Allocate space for the code
2423   ResourceMark rm;
2424   // Setup code generation tools
2425   CodeBuffer buffer("uncommon_trap_blob", 2048, 1024);
2426   MacroAssembler* masm = new MacroAssembler(&buffer);
2427 
2428   assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
2429 
2430   address start = __ pc();
2431 
2432   // Push self-frame.  We get here with a return address in LR
2433   // and sp should be 16 byte aligned
2434   // push rfp and retaddr by hand
2435   __ strd(rfp, lr, Address(__ pre(sp, -2 * wordSize)));
2436   // we don't expect an arg reg save area
2437 #ifndef PRODUCT
2438   assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
2439 #endif
2440   // compiler left unloaded_class_index in j_rarg0 move to where the
2441   // runtime expects it.
2442   if (c_rarg1 != j_rarg0) {
2443     __ mov(c_rarg1, j_rarg0);
2444   }
2445 
2446   // we need to set the past SP to the stack pointer of the stub frame
2447   // and the pc to the address where this runtime call will return
2448   // although actually any pc in this code blob will do).
2449   Label retaddr;
2450   __ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
2451 
2452   // Call C code.  Need thread but NOT official VM entry
2453   // crud.  We cannot block on this call, no GC can happen.  Call should
2454   // capture callee-saved registers as well as return values.
2455   // Thread is in rdi already.
2456   //
2457   // UnrollBlock* uncommon_trap(JavaThread* thread, jint unloaded_class_index);
2458   //
2459   // n.b. 2 gp args, 0 fp args, integral return type
2460 
2461   __ mov(c_rarg0, rthread);
2462   __ lea(rscratch1,
2463          RuntimeAddress(CAST_FROM_FN_PTR(address,
2464                                          Deoptimization::uncommon_trap)));
2465   __ bl(rscratch1);
2466   __ bind(retaddr);
2467 
2468   // Set an oopmap for the call site
2469   OopMapSet* oop_maps = new OopMapSet();
2470   OopMap* map = new OopMap(SimpleRuntimeFrame::framesize, 0);
2471 
2472   // location of rfp is known implicitly by the frame sender code
2473 
2474   oop_maps->add_gc_map(__ pc() - start, map);
2475 
2476   __ reset_last_Java_frame(false, true);
2477 
2478   // move UnrollBlock* into r4
2479   __ mov(r4, r0);
2480 
2481   // Pop all the frames we must move/replace.
2482   //
2483   // Frame picture (youngest to oldest)
2484   // 1: self-frame (no frame link)
2485   // 2: deopting frame  (no frame link)
2486   // 3: caller of deopting frame (could be compiled/interpreted).
2487 
2488   // Pop self-frame.  We have no frame, and must rely only on r0 and sp.
2489   __ add(sp, sp, (SimpleRuntimeFrame::framesize) << LogBytesPerInt); // Epilog!
2490 
2491   // Pop deoptimized frame (int)
2492   __ ldr(r2, Address(r4,
2493                      Deoptimization::UnrollBlock::
2494                      size_of_deoptimized_frame_offset_in_bytes()));
2495   __ sub(r2, r2, 2 * wordSize);
2496   __ add(sp, sp, r2);
2497   __ ldrd(rfp, lr, __ post(sp, 2 * wordSize));
2498   // LR should now be the return address to the caller (3) frame
2499 
2500 #ifdef ASSERT
2501   // Compilers generate code that bang the stack by as much as the
2502   // interpreter would need. So this stack banging should never
2503   // trigger a fault. Verify that it does not on non product builds.
2504   if (UseStackBanging) {
2505     __ ldr(r1, Address(r4,
2506                        Deoptimization::UnrollBlock::
2507                        total_frame_sizes_offset_in_bytes()));
2508     __ bang_stack_size(r1, r2);
2509   }
2510 #endif
2511 
2512   // Load address of array of frame pcs into r2 (address*)
2513   __ ldr(r2, Address(r4,
2514                      Deoptimization::UnrollBlock::frame_pcs_offset_in_bytes()));
2515 
2516   // Load address of array of frame sizes into r5 (intptr_t*)
2517   __ ldr(r5, Address(r4,
2518                      Deoptimization::UnrollBlock::
2519                      frame_sizes_offset_in_bytes()));
2520 
2521   // Counter
2522   __ ldr(r3, Address(r4,
2523                      Deoptimization::UnrollBlock::
2524                      number_of_frames_offset_in_bytes())); // (int)
2525 
2526   // Now adjust the caller's stack to make up for the extra locals but
2527   // record the original sp so that we can save it in the skeletal
2528   // interpreter frame and the stack walking of interpreter_sender
2529   // will get the unextended sp value and not the "real" sp value.
2530 
2531   const Register sender_sp = r8;
2532 
2533   __ mov(sender_sp, sp);
2534   __ ldr(r1, Address(r4,
2535                      Deoptimization::UnrollBlock::
2536                      caller_adjustment_offset_in_bytes())); // (int)
2537   __ sub(sp, sp, r1);
2538 
2539   __ mov(rscratch1, 0);
2540   // Push interpreter frames in a loop
2541   Label loop;
2542   __ bind(loop);
2543   __ ldr(r1, Address(r5, 0));       // Load frame size
2544   __ sub(r1, r1, 2 * wordSize);     // We'll push pc and rfp by hand
2545   __ ldr(lr, Address(r2, 0));       // Save return address
2546   __ enter();                       // and old rfp & set new rfp
2547   __ sub(sp, sp, r1);               // Prolog
2548   __ str(sender_sp, Address(rfp, frame::interpreter_frame_sender_sp_offset * wordSize)); // Make it walkable
2549   // This value is corrected by layout_activation_impl
2550   __ str(rscratch1, Address(rfp, frame::interpreter_frame_last_sp_offset * wordSize)); //zero it
2551   __ mov(sender_sp, sp);          // Pass sender_sp to next frame
2552   __ add(r5, r5, wordSize);       // Bump array pointer (sizes)
2553   __ add(r2, r2, wordSize);       // Bump array pointer (pcs)
2554   __ subs(r3, r3, 1);             // Decrement counter
2555   __ b(loop, Assembler::GT);
2556   __ ldr(lr, Address(r2, 0));     // save final return address
2557   // Re-push self-frame
2558   __ enter();                     // & old rfp & set new rfp
2559 
2560   // Use rfp because the frames look interpreted now
2561   // Save "the_pc" since it cannot easily be retrieved using the last_java_SP after we aligned SP.
2562   // Don't need the precise return PC here, just precise enough to point into this code blob.
2563   address the_pc = __ pc();
2564   __ set_last_Java_frame(sp, rfp, the_pc, rscratch1);
2565 
2566   // Call C code.  Need thread but NOT official VM entry
2567   // crud.  We cannot block on this call, no GC can happen.  Call should
2568   // restore return values to their stack-slots with the new SP.
2569   // Thread is in rdi already.
2570   //
2571   // BasicType unpack_frames(JavaThread* thread, int exec_mode);
2572   //
2573   // n.b. 2 gp args, 0 fp args, integral return type
2574 
2575   // sp should already be aligned
2576   __ mov(c_rarg0, rthread);
2577   __ mov(c_rarg1, (unsigned)Deoptimization::Unpack_uncommon_trap);
2578   __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::unpack_frames)));
2579   __ bl(rscratch1);
2580 
2581   // Set an oopmap for the call site
2582   // Use the same PC we used for the last java frame
2583   oop_maps->add_gc_map(the_pc - start, new OopMap(SimpleRuntimeFrame::framesize, 0));
2584 
2585   // Clear fp AND pc
2586   __ reset_last_Java_frame(true, true);
2587 
2588   // Pop self-frame.
2589   __ leave();                 // Epilog
2590 
2591   // Jump to interpreter
2592   __ b(lr);
2593 
2594   // Make sure all code is generated
2595   masm->flush();
2596 
2597   _uncommon_trap_blob =  UncommonTrapBlob::create(&buffer, oop_maps,
2598                                                  SimpleRuntimeFrame::framesize >> 1);
2599 
2600 } */
2601 #endif // COMPILER2
2602 
2603 
2604 //------------------------------generate_handler_blob------
2605 //
2606 // Generate a special Compile2Runtime blob that saves all registers,
2607 // and setup oopmap.
2608 //
2609 SafepointBlob* SharedRuntime::generate_handler_blob(address call_ptr, int poll_type) {
2610   ResourceMark rm;
2611   OopMapSet *oop_maps = new OopMapSet();
2612   OopMap* map;
2613 
2614   // Allocate space for the code.  Setup code generation tools.
2615   CodeBuffer buffer("handler_blob", 2048, 1024);
2616   MacroAssembler* masm = new MacroAssembler(&buffer);
2617 
2618   address start   = __ pc();
2619   address call_pc = NULL;
2620   int frame_size_in_words;
2621   bool cause_return = (poll_type == POLL_AT_RETURN);
2622   bool save_vectors = (poll_type == POLL_AT_VECTOR_LOOP);
2623 
2624   // Save registers, fpu state, and flags
2625   map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
2626 
2627   // The following is basically a call_VM.  However, we need the precise
2628   // address of the call in order to generate an oopmap. Hence, we do all the
2629   // work outselves.
2630 
2631   Label retaddr;
2632   __ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
2633 
2634   // The return address must always be correct so that frame constructor never
2635   // sees an invalid pc.
2636 
2637   if (!cause_return) {
2638     // overwrite the return address pushed by save_live_registers
2639     __ ldr(lr, Address(rthread, JavaThread::saved_exception_pc_offset()));
2640     __ str(lr, Address(rfp));
2641   }
2642 
2643   // Do the call
2644   __ mov(c_rarg0, rthread);
2645   __ lea(rscratch1, RuntimeAddress(call_ptr));
2646   __ bl(rscratch1);
2647   __ bind(retaddr);
2648 
2649   // Set an oopmap for the call site.  This oopmap will map all
2650   // oop-registers and debug-info registers as callee-saved.  This
2651   // will allow deoptimization at this safepoint to find all possible
2652   // debug-info recordings, as well as let GC find all oops.
2653 
2654   oop_maps->add_gc_map( __ pc() - start, map);
2655 
2656   Label noException;
2657 
2658   __ reset_last_Java_frame(false, true);
2659 
2660   __ maybe_isb();
2661   __ membar(Assembler::LoadLoad | Assembler::LoadStore);
2662 
2663   __ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
2664   __ cbz(rscratch1, noException);
2665 
2666   // Exception pending
2667 
2668   RegisterSaver::restore_live_registers(masm);
2669 
2670   __ far_jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
2671 
2672   // No exception case
2673   __ bind(noException);
2674 
2675   // Normal exit, restore registers and exit.
2676   RegisterSaver::restore_live_registers(masm);
2677 
2678   __ b(lr);
2679 
2680   // Make sure all code is generated
2681   masm->flush();
2682 
2683   // Fill-out other meta info
2684   return SafepointBlob::create(&buffer, oop_maps, frame_size_in_words);
2685 }
2686 
2687 //
2688 // generate_resolve_blob - call resolution (static/virtual/opt-virtual/ic-miss
2689 //
2690 // Generate a stub that calls into vm to find out the proper destination
2691 // of a java call. All the argument registers are live at this point
2692 // but since this is generic code we don't know what they are and the caller
2693 // must do any gc of the args.
2694 //
2695 RuntimeStub* SharedRuntime::generate_resolve_blob(address destination, const char* name) {
2696   assert (StubRoutines::forward_exception_entry() != NULL, "must be generated before");
2697 
2698   // allocate space for the code
2699   ResourceMark rm;
2700 
2701   //CodeBuffer buffer(name, 1000, 512);
2702   CodeBuffer buffer(name, 2048, 512 ); // changed as error later
2703   MacroAssembler* masm                = new MacroAssembler(&buffer);
2704 
2705   int frame_size_in_words;
2706 
2707   OopMapSet *oop_maps = new OopMapSet();
2708   OopMap* map = NULL;
2709 
2710   int start = __ offset();
2711 
2712   map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
2713 
2714   int frame_complete = __ offset();
2715 
2716   {
2717     Label retaddr;
2718     __ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
2719 
2720     __ mov(c_rarg0, rthread);
2721     __ lea(rscratch1, RuntimeAddress(destination));
2722 
2723     __ bl(rscratch1);
2724     __ bind(retaddr);
2725   }
2726 
2727   // Set an oopmap for the call site.
2728   // We need this not only for callee-saved registers, but also for volatile
2729   // registers that the compiler might be keeping live across a safepoint.
2730 
2731   oop_maps->add_gc_map( __ offset() - start, map);
2732 
2733   __ maybe_isb();
2734 
2735   // r0 contains the address we are going to jump to assuming no exception got installed
2736 
2737   // clear last_Java_sp
2738   // TODO x86 have different action: reset_last_Java_frame(thread, true(fp), false(pc));
2739   // TODO below is false(fp), true(pc)
2740   __ reset_last_Java_frame(false, true);
2741   // check for pending exceptions
2742   Label pending;
2743   __ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
2744   __ cbnz(rscratch1, pending);
2745 
2746   // get the returned Method*
2747   __ get_vm_result_2(rmethod, rthread);
2748   __ str(rmethod, Address(sp, RegisterSaver::offset_in_bytes(RegisterSaver::rmethod_off)));
2749 
2750   // r0 is where we want to jump, overwrite rscratch1 which is saved and scratch
2751   __ str(r0, Address(sp, RegisterSaver::offset_in_bytes(RegisterSaver::rscratch1_off)));
2752   RegisterSaver::restore_live_registers(masm);
2753 
2754   // We are back the the original state on entry and ready to go.
2755 
2756   __ b(rscratch1);
2757 
2758   // Pending exception after the safepoint
2759 
2760   __ bind(pending);
2761 
2762   RegisterSaver::restore_live_registers(masm);
2763 
2764   // exception pending => remove activation and forward to exception handler
2765   __ mov(rscratch1, 0);
2766   __ str(rscratch1, Address(rthread, JavaThread::vm_result_offset()));
2767 
2768   __ ldr(r0, Address(rthread, Thread::pending_exception_offset()));
2769   __ far_jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
2770 
2771   // -------------
2772   // make sure all code is generated
2773   masm->flush();
2774 
2775   // return the  blob
2776   // frame_size_words or bytes??
2777   return RuntimeStub::new_runtime_stub(name, &buffer, frame_complete, frame_size_in_words, oop_maps, true);
2778 }
2779 
2780 
2781 #ifdef COMPILER2
2782 // This is here instead of runtime_x86_64.cpp because it uses SimpleRuntimeFrame
2783 //
2784 //------------------------------generate_exception_blob---------------------------
2785 // creates exception blob at the end
2786 // Using exception blob, this code is jumped from a compiled method.
2787 // (see emit_exception_handler in x86_64.ad file)
2788 //
2789 // Given an exception pc at a call we call into the runtime for the
2790 // handler in this method. This handler might merely restore state
2791 // (i.e. callee save registers) unwind the frame and jump to the
2792 // exception handler for the nmethod if there is no Java level handler
2793 // for the nmethod.
2794 //
2795 // This code is entered with a jmp.
2796 //
2797 // Arguments:
2798 //   r0: exception oop
2799 //   r3: exception pc
2800 //
2801 // Results:
2802 //   r0: exception oop
2803 //   r3: exception pc in caller or ???
2804 //   destination: exception handler of caller
2805 //
2806 // Note: the exception pc MUST be at a call (precise debug information)
2807 //       Registers r0, r3, r2, r4, r5, r8-r11 are not callee saved.
2808 //
2809 
2810 void OptoRuntime::generate_exception_blob() {
2811   assert(!OptoRuntime::is_callee_saved_register(R3_num), "");
2812   assert(!OptoRuntime::is_callee_saved_register(R0_num), "");
2813   assert(!OptoRuntime::is_callee_saved_register(R2_num), "");
2814 
2815   assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
2816 
2817   // Allocate space for the code
2818   ResourceMark rm;
2819   // Setup code generation tools
2820   CodeBuffer buffer("exception_blob", 2048, 1024);
2821   MacroAssembler* masm = new MacroAssembler(&buffer);
2822 
2823   __ stop("FIXME generate_exception_blob");
2824   // TODO check various assumptions made here
2825   //
2826   // make sure we do so before running this
2827 
2828   address start = __ pc();
2829 
2830   // push rfp and retaddr by hand
2831   // Exception pc is 'return address' for stack walker
2832   __ strd(rfp, lr, Address(__ pre(sp, -2 * wordSize)));
2833   // there are no callee save registers and we don't expect an
2834   // arg reg save area
2835 #ifndef PRODUCT
2836   assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
2837 #endif
2838   // Store exception in Thread object. We cannot pass any arguments to the
2839   // handle_exception call, since we do not want to make any assumption
2840   // about the size of the frame where the exception happened in.
2841   __ str(r0, Address(rthread, JavaThread::exception_oop_offset()));
2842   __ str(r3, Address(rthread, JavaThread::exception_pc_offset()));
2843 
2844   // This call does all the hard work.  It checks if an exception handler
2845   // exists in the method.
2846   // If so, it returns the handler address.
2847   // If not, it prepares for stack-unwinding, restoring the callee-save
2848   // registers of the frame being removed.
2849   //
2850   // address OptoRuntime::handle_exception_C(JavaThread* thread)
2851   //
2852   // n.b. 1 gp arg, 0 fp args, integral return type
2853 
2854   // the stack should always be aligned
2855   address the_pc = __ pc();
2856   __ set_last_Java_frame(sp, noreg, the_pc, rscratch1);
2857   __ mov(c_rarg0, rthread);
2858   __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, OptoRuntime::handle_exception_C)));
2859   __ bl(rscratch1);
2860   __ maybe_isb();
2861 
2862   // Set an oopmap for the call site.  This oopmap will only be used if we
2863   // are unwinding the stack.  Hence, all locations will be dead.
2864   // Callee-saved registers will be the same as the frame above (i.e.,
2865   // handle_exception_stub), since they were restored when we got the
2866   // exception.
2867 
2868   OopMapSet* oop_maps = new OopMapSet();
2869 
2870   oop_maps->add_gc_map(the_pc - start, new OopMap(SimpleRuntimeFrame::framesize, 0));
2871 
2872   __ reset_last_Java_frame(false, true);
2873 
2874   // Restore callee-saved registers
2875 
2876   // rfp is an implicitly saved callee saved register (i.e. the calling
2877   // convention will save restore it in prolog/epilog) Other than that
2878   // there are no callee save registers now that adapter frames are gone.
2879   // and we dont' expect an arg reg save area
2880   __ ldrd(rfp, r3, Address(__ post(sp, 2 * wordSize)));
2881 
2882   // r0: exception handler
2883 
2884   // We have a handler in r0 (could be deopt blob).
2885   __ mov(r8, r0);
2886 
2887   // Get the exception oop
2888   __ ldr(r0, Address(rthread, JavaThread::exception_oop_offset()));
2889   // Get the exception pc in case we are deoptimized
2890   __ ldr(r4, Address(rthread, JavaThread::exception_pc_offset()));
2891   __ mov(rscratch1, 0);
2892 #ifdef ASSERT
2893   __ str(rscratch1, Address(rthread, JavaThread::exception_handler_pc_offset()));
2894   __ str(rscratch1, Address(rthread, JavaThread::exception_pc_offset()));
2895 #endif
2896   // Clear the exception oop so GC no longer processes it as a root.
2897   __ str(rscratch1, Address(rthread, JavaThread::exception_oop_offset()));
2898 
2899   // r0: exception oop
2900   // r8:  exception handler
2901   // r4: exception pc
2902   // Jump to handler
2903 
2904   __ b(r8);
2905 
2906   // Make sure all code is generated
2907   masm->flush();
2908 
2909   // Set exception blob
2910   _exception_blob =  ExceptionBlob::create(&buffer, oop_maps, SimpleRuntimeFrame::framesize >> 1);
2911 }
2912 #endif // COMPILER2