1 /*
   2  * Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "asm/assembler.inline.hpp"
  27 #include "c1/c1_Compilation.hpp"
  28 #include "c1/c1_Instruction.hpp"
  29 #include "c1/c1_InstructionPrinter.hpp"
  30 #include "c1/c1_LIRAssembler.hpp"
  31 #include "c1/c1_MacroAssembler.hpp"
  32 #include "c1/c1_ValueStack.hpp"
  33 #include "ci/ciInstance.hpp"
  34 #include "gc/shared/barrierSet.hpp"
  35 #include "runtime/os.hpp"
  36 
  37 void LIR_Assembler::patching_epilog(PatchingStub* patch, LIR_PatchCode patch_code, Register obj, CodeEmitInfo* info) {
  38   // We must have enough patching space so that call can be inserted.
  39   // We cannot use fat nops here, since the concurrent code rewrite may transiently
  40   // create the illegal instruction sequence.
  41   while ((intx) _masm->pc() - (intx) patch->pc_start() < NativeGeneralJump::instruction_size) {
  42     _masm->nop();
  43   }
  44   patch->install(_masm, patch_code, obj, info);
  45   append_code_stub(patch);
  46 
  47 #ifdef ASSERT
  48   Bytecodes::Code code = info->scope()->method()->java_code_at_bci(info->stack()->bci());
  49   if (patch->id() == PatchingStub::access_field_id) {
  50     switch (code) {
  51       case Bytecodes::_putstatic:
  52       case Bytecodes::_getstatic:
  53       case Bytecodes::_putfield:
  54       case Bytecodes::_getfield:
  55         break;
  56       default:
  57         ShouldNotReachHere();
  58     }
  59   } else if (patch->id() == PatchingStub::load_klass_id) {
  60     switch (code) {
  61       case Bytecodes::_new:
  62       case Bytecodes::_anewarray:
  63       case Bytecodes::_multianewarray:
  64       case Bytecodes::_instanceof:
  65       case Bytecodes::_checkcast:
  66         break;
  67       default:
  68         ShouldNotReachHere();
  69     }
  70   } else if (patch->id() == PatchingStub::load_mirror_id) {
  71     switch (code) {
  72       case Bytecodes::_putstatic:
  73       case Bytecodes::_getstatic:
  74       case Bytecodes::_ldc:
  75       case Bytecodes::_ldc_w:
  76         break;
  77       default:
  78         ShouldNotReachHere();
  79     }
  80   } else if (patch->id() == PatchingStub::load_appendix_id) {
  81     Bytecodes::Code bc_raw = info->scope()->method()->raw_code_at_bci(info->stack()->bci());
  82     assert(Bytecodes::has_optional_appendix(bc_raw), "unexpected appendix resolution");
  83   } else {
  84     ShouldNotReachHere();
  85   }
  86 #endif
  87 }
  88 
  89 PatchingStub::PatchID LIR_Assembler::patching_id(CodeEmitInfo* info) {
  90   IRScope* scope = info->scope();
  91   Bytecodes::Code bc_raw = scope->method()->raw_code_at_bci(info->stack()->bci());
  92   if (Bytecodes::has_optional_appendix(bc_raw)) {
  93     return PatchingStub::load_appendix_id;
  94   }
  95   return PatchingStub::load_mirror_id;
  96 }
  97 
  98 //---------------------------------------------------------------
  99 
 100 
 101 LIR_Assembler::LIR_Assembler(Compilation* c):
 102    _masm(c->masm())
 103  , _bs(BarrierSet::barrier_set())
 104  , _compilation(c)
 105  , _frame_map(c->frame_map())
 106  , _current_block(NULL)
 107  , _pending_non_safepoint(NULL)
 108  , _pending_non_safepoint_offset(0)
 109 {
 110   _slow_case_stubs = new CodeStubList();
 111 }
 112 
 113 
 114 LIR_Assembler::~LIR_Assembler() {
 115   // The unwind handler label may be unnbound if this destructor is invoked because of a bail-out.
 116   // Reset it here to avoid an assertion.
 117   _unwind_handler_entry.reset();
 118 }
 119 
 120 
 121 void LIR_Assembler::check_codespace() {
 122   CodeSection* cs = _masm->code_section();
 123   if (cs->remaining() < (int)(NOT_LP64(1*K)LP64_ONLY(2*K))) {
 124     BAILOUT("CodeBuffer overflow");
 125   }
 126 }
 127 
 128 
 129 void LIR_Assembler::append_code_stub(CodeStub* stub) {
 130   _slow_case_stubs->append(stub);
 131 }
 132 
 133 void LIR_Assembler::emit_stubs(CodeStubList* stub_list) {
 134   for (int m = 0; m < stub_list->length(); m++) {
 135     CodeStub* s = stub_list->at(m);
 136 
 137     check_codespace();
 138     CHECK_BAILOUT();
 139 
 140 #ifndef PRODUCT
 141     if (CommentedAssembly) {
 142       stringStream st;
 143       s->print_name(&st);
 144       st.print(" slow case");
 145       _masm->block_comment(st.as_string());
 146     }
 147 #endif
 148     s->emit_code(this);
 149 #ifdef ASSERT
 150     s->assert_no_unbound_labels();
 151 #endif
 152   }
 153 }
 154 
 155 
 156 void LIR_Assembler::emit_slow_case_stubs() {
 157   emit_stubs(_slow_case_stubs);
 158 }
 159 
 160 
 161 bool LIR_Assembler::needs_icache(ciMethod* method) const {
 162   return !method->is_static();
 163 }
 164 
 165 
 166 int LIR_Assembler::code_offset() const {
 167   return _masm->offset();
 168 }
 169 
 170 
 171 address LIR_Assembler::pc() const {
 172   return _masm->pc();
 173 }
 174 
 175 // To bang the stack of this compiled method we use the stack size
 176 // that the interpreter would need in case of a deoptimization. This
 177 // removes the need to bang the stack in the deoptimization blob which
 178 // in turn simplifies stack overflow handling.
 179 int LIR_Assembler::bang_size_in_bytes() const {
 180   return MAX2(initial_frame_size_in_bytes() + os::extra_bang_size_in_bytes(), _compilation->interpreter_frame_size());
 181 }
 182 
 183 void LIR_Assembler::emit_exception_entries(ExceptionInfoList* info_list) {
 184   for (int i = 0; i < info_list->length(); i++) {
 185     XHandlers* handlers = info_list->at(i)->exception_handlers();
 186 
 187     for (int j = 0; j < handlers->length(); j++) {
 188       XHandler* handler = handlers->handler_at(j);
 189       assert(handler->lir_op_id() != -1, "handler not processed by LinearScan");
 190       assert(handler->entry_code() == NULL ||
 191              handler->entry_code()->instructions_list()->last()->code() == lir_branch ||
 192              handler->entry_code()->instructions_list()->last()->code() == lir_delay_slot, "last operation must be branch");
 193 
 194       if (handler->entry_pco() == -1) {
 195         // entry code not emitted yet
 196         if (handler->entry_code() != NULL && handler->entry_code()->instructions_list()->length() > 1) {
 197           handler->set_entry_pco(code_offset());
 198           if (CommentedAssembly) {
 199             _masm->block_comment("Exception adapter block");
 200           }
 201           emit_lir_list(handler->entry_code());
 202         } else {
 203           handler->set_entry_pco(handler->entry_block()->exception_handler_pco());
 204         }
 205 
 206         assert(handler->entry_pco() != -1, "must be set now");
 207       }
 208     }
 209   }
 210 }
 211 
 212 
 213 void LIR_Assembler::emit_code(BlockList* hir) {
 214   if (PrintLIR) {
 215     print_LIR(hir);
 216   }
 217 
 218   int n = hir->length();
 219   for (int i = 0; i < n; i++) {
 220     emit_block(hir->at(i));
 221     CHECK_BAILOUT();
 222   }
 223 
 224   flush_debug_info(code_offset());
 225 
 226   DEBUG_ONLY(check_no_unbound_labels());
 227 }
 228 
 229 
 230 void LIR_Assembler::emit_block(BlockBegin* block) {
 231   if (block->is_set(BlockBegin::backward_branch_target_flag)) {
 232     align_backward_branch_target();
 233   }
 234 
 235   // if this block is the start of an exception handler, record the
 236   // PC offset of the first instruction for later construction of
 237   // the ExceptionHandlerTable
 238   if (block->is_set(BlockBegin::exception_entry_flag)) {
 239     block->set_exception_handler_pco(code_offset());
 240   }
 241 
 242 #ifndef PRODUCT
 243   if (PrintLIRWithAssembly) {
 244     // don't print Phi's
 245     InstructionPrinter ip(false);
 246     block->print(ip);
 247   }
 248 #endif /* PRODUCT */
 249 
 250   assert(block->lir() != NULL, "must have LIR");
 251   X86_ONLY(assert(_masm->rsp_offset() == 0, "frame size should be fixed"));
 252 
 253 #ifndef PRODUCT
 254   if (CommentedAssembly) {
 255     stringStream st;
 256     st.print_cr(" block B%d [%d, %d]", block->block_id(), block->bci(), block->end()->printable_bci());
 257     _masm->block_comment(st.as_string());
 258   }
 259 #endif
 260 
 261   emit_lir_list(block->lir());
 262 
 263   X86_ONLY(assert(_masm->rsp_offset() == 0, "frame size should be fixed"));
 264 }
 265 
 266 
 267 void LIR_Assembler::emit_lir_list(LIR_List* list) {
 268   peephole(list);
 269 
 270   int n = list->length();
 271   for (int i = 0; i < n; i++) {
 272     LIR_Op* op = list->at(i);
 273 
 274     check_codespace();
 275     CHECK_BAILOUT();
 276 
 277 #ifndef PRODUCT
 278     if (CommentedAssembly) {
 279       // Don't record out every op since that's too verbose.  Print
 280       // branches since they include block and stub names.  Also print
 281       // patching moves since they generate funny looking code.
 282       if (op->code() == lir_branch ||
 283           (op->code() == lir_move && op->as_Op1()->patch_code() != lir_patch_none) ||
 284           (op->code() == lir_leal && op->as_Op1()->patch_code() != lir_patch_none)) {
 285         stringStream st;
 286         op->print_on(&st);
 287         _masm->block_comment(st.as_string());
 288       }
 289     }
 290     if (PrintLIRWithAssembly) {
 291       // print out the LIR operation followed by the resulting assembly
 292       list->at(i)->print(); tty->cr();
 293     }
 294 #endif /* PRODUCT */
 295 
 296     op->emit_code(this);
 297 
 298     if (compilation()->debug_info_recorder()->recording_non_safepoints()) {
 299       process_debug_info(op);
 300     }
 301 
 302 #ifndef PRODUCT
 303     if (PrintLIRWithAssembly) {
 304       _masm->code()->decode();
 305     }
 306 #endif /* PRODUCT */
 307   }
 308 }
 309 
 310 #ifdef ASSERT
 311 void LIR_Assembler::check_no_unbound_labels() {
 312   CHECK_BAILOUT();
 313 
 314   for (int i = 0; i < _branch_target_blocks.length() - 1; i++) {
 315     if (!_branch_target_blocks.at(i)->label()->is_bound()) {
 316       tty->print_cr("label of block B%d is not bound", _branch_target_blocks.at(i)->block_id());
 317       assert(false, "unbound label");
 318     }
 319   }
 320 }
 321 #endif
 322 
 323 //----------------------------------debug info--------------------------------
 324 
 325 
 326 void LIR_Assembler::add_debug_info_for_branch(CodeEmitInfo* info) {
 327   int pc_offset = code_offset();
 328   flush_debug_info(pc_offset);
 329   info->record_debug_info(compilation()->debug_info_recorder(), pc_offset);
 330   if (info->exception_handlers() != NULL) {
 331     compilation()->add_exception_handlers_for_pco(pc_offset, info->exception_handlers());
 332   }
 333 }
 334 
 335 
 336 void LIR_Assembler::add_call_info(int pc_offset, CodeEmitInfo* cinfo) {
 337   flush_debug_info(pc_offset);
 338   cinfo->record_debug_info(compilation()->debug_info_recorder(), pc_offset);
 339   if (cinfo->exception_handlers() != NULL) {
 340     compilation()->add_exception_handlers_for_pco(pc_offset, cinfo->exception_handlers());
 341   }
 342 }
 343 
 344 static ValueStack* debug_info(Instruction* ins) {
 345   StateSplit* ss = ins->as_StateSplit();
 346   if (ss != NULL) return ss->state();
 347   return ins->state_before();
 348 }
 349 
 350 void LIR_Assembler::process_debug_info(LIR_Op* op) {
 351   Instruction* src = op->source();
 352   if (src == NULL)  return;
 353   int pc_offset = code_offset();
 354   if (_pending_non_safepoint == src) {
 355     _pending_non_safepoint_offset = pc_offset;
 356     return;
 357   }
 358   ValueStack* vstack = debug_info(src);
 359   if (vstack == NULL)  return;
 360   if (_pending_non_safepoint != NULL) {
 361     // Got some old debug info.  Get rid of it.
 362     if (debug_info(_pending_non_safepoint) == vstack) {
 363       _pending_non_safepoint_offset = pc_offset;
 364       return;
 365     }
 366     if (_pending_non_safepoint_offset < pc_offset) {
 367       record_non_safepoint_debug_info();
 368     }
 369     _pending_non_safepoint = NULL;
 370   }
 371   // Remember the debug info.
 372   if (pc_offset > compilation()->debug_info_recorder()->last_pc_offset()) {
 373     _pending_non_safepoint = src;
 374     _pending_non_safepoint_offset = pc_offset;
 375   }
 376 }
 377 
 378 // Index caller states in s, where 0 is the oldest, 1 its callee, etc.
 379 // Return NULL if n is too large.
 380 // Returns the caller_bci for the next-younger state, also.
 381 static ValueStack* nth_oldest(ValueStack* s, int n, int& bci_result) {
 382   ValueStack* t = s;
 383   for (int i = 0; i < n; i++) {
 384     if (t == NULL)  break;
 385     t = t->caller_state();
 386   }
 387   if (t == NULL)  return NULL;
 388   for (;;) {
 389     ValueStack* tc = t->caller_state();
 390     if (tc == NULL)  return s;
 391     t = tc;
 392     bci_result = tc->bci();
 393     s = s->caller_state();
 394   }
 395 }
 396 
 397 void LIR_Assembler::record_non_safepoint_debug_info() {
 398   int         pc_offset = _pending_non_safepoint_offset;
 399   ValueStack* vstack    = debug_info(_pending_non_safepoint);
 400   int         bci       = vstack->bci();
 401 
 402   DebugInformationRecorder* debug_info = compilation()->debug_info_recorder();
 403   assert(debug_info->recording_non_safepoints(), "sanity");
 404 
 405   debug_info->add_non_safepoint(pc_offset);
 406 
 407   // Visit scopes from oldest to youngest.
 408   for (int n = 0; ; n++) {
 409     int s_bci = bci;
 410     ValueStack* s = nth_oldest(vstack, n, s_bci);
 411     if (s == NULL)  break;
 412     IRScope* scope = s->scope();
 413     //Always pass false for reexecute since these ScopeDescs are never used for deopt
 414     methodHandle null_mh;
 415     debug_info->describe_scope(pc_offset, null_mh, scope->method(), s->bci(), false/*reexecute*/);
 416   }
 417 
 418   debug_info->end_non_safepoint(pc_offset);
 419 }
 420 
 421 
 422 ImplicitNullCheckStub* LIR_Assembler::add_debug_info_for_null_check_here(CodeEmitInfo* cinfo) {
 423   return add_debug_info_for_null_check(code_offset(), cinfo);
 424 }
 425 
 426 ImplicitNullCheckStub* LIR_Assembler::add_debug_info_for_null_check(int pc_offset, CodeEmitInfo* cinfo) {
 427   ImplicitNullCheckStub* stub = new ImplicitNullCheckStub(pc_offset, cinfo);
 428   append_code_stub(stub);
 429   return stub;
 430 }
 431 
 432 void LIR_Assembler::add_debug_info_for_div0_here(CodeEmitInfo* info) {
 433   add_debug_info_for_div0(code_offset(), info);
 434 }
 435 
 436 void LIR_Assembler::add_debug_info_for_div0(int pc_offset, CodeEmitInfo* cinfo) {
 437   DivByZeroStub* stub = new DivByZeroStub(pc_offset, cinfo);
 438   append_code_stub(stub);
 439 }
 440 
 441 void LIR_Assembler::emit_rtcall(LIR_OpRTCall* op) {
 442   rt_call(op->result_opr(), op->addr(), op->arguments(), op->tmp(), op->info());
 443 }
 444 
 445 
 446 void LIR_Assembler::emit_call(LIR_OpJavaCall* op) {
 447   verify_oop_map(op->info());
 448 
 449   // must align calls sites, otherwise they can't be updated atomically
 450   align_call(op->code());
 451 
 452   // emit the static call stub stuff out of line
 453   emit_static_call_stub();
 454   CHECK_BAILOUT();
 455 
 456   switch (op->code()) {
 457   case lir_static_call:
 458   case lir_dynamic_call:
 459     call(op, relocInfo::static_call_type);
 460     break;
 461   case lir_optvirtual_call:
 462     call(op, relocInfo::opt_virtual_call_type);
 463     break;
 464   case lir_icvirtual_call:
 465     ic_call(op);
 466     break;
 467   case lir_virtual_call:
 468     vtable_call(op);
 469     break;
 470   default:
 471     fatal("unexpected op code: %s", op->name());
 472     break;
 473   }
 474 
 475   // JSR 292
 476   // Record if this method has MethodHandle invokes.
 477   if (op->is_method_handle_invoke()) {
 478     compilation()->set_has_method_handle_invokes(true);
 479   }
 480 
 481 #if defined(X86) && defined(TIERED)
 482   // C2 leave fpu stack dirty clean it
 483   if (UseSSE < 2) {
 484     int i;
 485     for ( i = 1; i <= 7 ; i++ ) {
 486       ffree(i);
 487     }
 488     if (!op->result_opr()->is_float_kind()) {
 489       ffree(0);
 490     }
 491   }
 492 #endif // X86 && TIERED
 493 }
 494 
 495 
 496 void LIR_Assembler::emit_opLabel(LIR_OpLabel* op) {
 497   _masm->bind (*(op->label()));
 498 }
 499 
 500 
 501 void LIR_Assembler::emit_op1(LIR_Op1* op) {
 502   switch (op->code()) {
 503     case lir_move:
 504       if (op->move_kind() == lir_move_volatile) {
 505         assert(op->patch_code() == lir_patch_none, "can't patch volatiles");
 506         volatile_move_op(op->in_opr(), op->result_opr(), op->type(), op->info());
 507       } else {
 508         move_op(op->in_opr(), op->result_opr(), op->type(),
 509                 op->patch_code(), op->info(), op->pop_fpu_stack(),
 510                 op->move_kind() == lir_move_unaligned,
 511                 op->move_kind() == lir_move_wide);
 512       }
 513       break;
 514 
 515     case lir_roundfp: {
 516       LIR_OpRoundFP* round_op = op->as_OpRoundFP();
 517       roundfp_op(round_op->in_opr(), round_op->tmp(), round_op->result_opr(), round_op->pop_fpu_stack());
 518       break;
 519     }
 520 
 521     case lir_return:
 522       return_op(op->in_opr());
 523       break;
 524 
 525     case lir_safepoint:
 526       if (compilation()->debug_info_recorder()->last_pc_offset() == code_offset()) {
 527         _masm->nop();
 528       }
 529       safepoint_poll(op->in_opr(), op->info());
 530       break;
 531 
 532     case lir_fxch:
 533       fxch(op->in_opr()->as_jint());
 534       break;
 535 
 536     case lir_fld:
 537       fld(op->in_opr()->as_jint());
 538       break;
 539 
 540     case lir_ffree:
 541       ffree(op->in_opr()->as_jint());
 542       break;
 543 
 544     case lir_branch:
 545       break;
 546 
 547     case lir_push:
 548       push(op->in_opr());
 549       break;
 550 
 551     case lir_pop:
 552       pop(op->in_opr());
 553       break;
 554 
 555     case lir_leal:
 556       leal(op->in_opr(), op->result_opr(), op->patch_code(), op->info());
 557       break;
 558 
 559     case lir_null_check: {
 560       ImplicitNullCheckStub* stub = add_debug_info_for_null_check_here(op->info());
 561 
 562       if (op->in_opr()->is_single_cpu()) {
 563         _masm->null_check(op->in_opr()->as_register(), stub->entry());
 564       } else {
 565         Unimplemented();
 566       }
 567       break;
 568     }
 569 
 570     case lir_monaddr:
 571       monitor_address(op->in_opr()->as_constant_ptr()->as_jint(), op->result_opr());
 572       break;
 573 
 574 #ifdef SPARC
 575     case lir_pack64:
 576       pack64(op->in_opr(), op->result_opr());
 577       break;
 578 
 579     case lir_unpack64:
 580       unpack64(op->in_opr(), op->result_opr());
 581       break;
 582 #endif
 583 
 584     case lir_unwind:
 585       unwind_op(op->in_opr());
 586       break;
 587 
 588     default:
 589       Unimplemented();
 590       break;
 591   }
 592 }
 593 
 594 
 595 void LIR_Assembler::emit_op0(LIR_Op0* op) {
 596   switch (op->code()) {
 597     case lir_word_align: {
 598       _masm->align(BytesPerWord);
 599       break;
 600     }
 601 
 602     case lir_nop:
 603       assert(op->info() == NULL, "not supported");
 604       _masm->nop();
 605       break;
 606 
 607     case lir_label:
 608       Unimplemented();
 609       break;
 610 
 611     case lir_build_frame:
 612       build_frame();
 613       break;
 614 
 615     case lir_std_entry:
 616       // init offsets
 617       offsets()->set_value(CodeOffsets::OSR_Entry, _masm->offset());
 618       _masm->align(CodeEntryAlignment);
 619       if (needs_icache(compilation()->method())) {
 620         check_icache();
 621       }
 622       offsets()->set_value(CodeOffsets::Verified_Entry, _masm->offset());
 623       _masm->verified_entry();
 624       build_frame();
 625       offsets()->set_value(CodeOffsets::Frame_Complete, _masm->offset());
 626       break;
 627 
 628     case lir_osr_entry:
 629       offsets()->set_value(CodeOffsets::OSR_Entry, _masm->offset());
 630       osr_entry();
 631       break;
 632 
 633     case lir_24bit_FPU:
 634       set_24bit_FPU();
 635       break;
 636 
 637     case lir_reset_FPU:
 638       reset_FPU();
 639       break;
 640 
 641     case lir_breakpoint:
 642       breakpoint();
 643       break;
 644 
 645     case lir_fpop_raw:
 646       fpop();
 647       break;
 648 
 649     case lir_membar:
 650       membar();
 651       break;
 652 
 653     case lir_membar_acquire:
 654       membar_acquire();
 655       break;
 656 
 657     case lir_membar_release:
 658       membar_release();
 659       break;
 660 
 661     case lir_membar_loadload:
 662       membar_loadload();
 663       break;
 664 
 665     case lir_membar_storestore:
 666       membar_storestore();
 667       break;
 668 
 669     case lir_membar_loadstore:
 670       membar_loadstore();
 671       break;
 672 
 673     case lir_membar_storeload:
 674       membar_storeload();
 675       break;
 676 
 677     case lir_get_thread:
 678       get_thread(op->result_opr());
 679       break;
 680 
 681     case lir_on_spin_wait:
 682       on_spin_wait();
 683       break;
 684 
 685     default:
 686       ShouldNotReachHere();
 687       break;
 688   }
 689 }
 690 
 691 
 692 void LIR_Assembler::emit_op2(LIR_Op2* op) {
 693   switch (op->code()) {
 694     case lir_cmp:
 695       if (op->info() != NULL) {
 696         assert(op->in_opr1()->is_address() || op->in_opr2()->is_address(),
 697                "shouldn't be codeemitinfo for non-address operands");
 698         add_debug_info_for_null_check_here(op->info()); // exception possible
 699       }
 700       comp_op(op->condition(), op->in_opr1(), op->in_opr2(), op);
 701       break;
 702 
 703     case lir_cmp_l2i:
 704     case lir_cmp_fd2i:
 705     case lir_ucmp_fd2i:
 706       comp_fl2i(op->code(), op->in_opr1(), op->in_opr2(), op->result_opr(), op);
 707       break;
 708 
 709     case lir_cmove:
 710       cmove(op->condition(), op->in_opr1(), op->in_opr2(), op->result_opr(), op->type());
 711       break;
 712 
 713     case lir_shl:
 714     case lir_shr:
 715     case lir_ushr:
 716       if (op->in_opr2()->is_constant()) {
 717         shift_op(op->code(), op->in_opr1(), op->in_opr2()->as_constant_ptr()->as_jint(), op->result_opr());
 718       } else {
 719         shift_op(op->code(), op->in_opr1(), op->in_opr2(), op->result_opr(), op->tmp1_opr());
 720       }
 721       break;
 722 
 723     case lir_add:
 724     case lir_sub:
 725     case lir_mul:
 726     case lir_mul_strictfp:
 727     case lir_div:
 728     case lir_div_strictfp:
 729     case lir_rem:
 730       assert(op->fpu_pop_count() < 2, "");
 731       arith_op(
 732         op->code(),
 733         op->in_opr1(),
 734         op->in_opr2(),
 735         op->result_opr(),
 736         op->info(),
 737         op->fpu_pop_count() == 1);
 738       break;
 739 
 740     case lir_abs:
 741     case lir_sqrt:
 742     case lir_tan:
 743     case lir_log10:
 744       intrinsic_op(op->code(), op->in_opr1(), op->in_opr2(), op->result_opr(), op);
 745       break;
 746 
 747     case lir_neg:
 748       negate(op->in_opr1(), op->result_opr(), op->in_opr2());
 749       break;
 750 
 751     case lir_logic_and:
 752     case lir_logic_or:
 753     case lir_logic_xor:
 754       logic_op(
 755         op->code(),
 756         op->in_opr1(),
 757         op->in_opr2(),
 758         op->result_opr());
 759       break;
 760 
 761     case lir_throw:
 762       throw_op(op->in_opr1(), op->in_opr2(), op->info());
 763       break;
 764 
 765     case lir_xadd:
 766     case lir_xchg:
 767       atomic_op(op->code(), op->in_opr1(), op->in_opr2(), op->result_opr(), op->tmp1_opr());
 768       break;
 769 
 770     default:
 771       Unimplemented();
 772       break;
 773   }
 774 }
 775 
 776 
 777 void LIR_Assembler::build_frame() {
 778   _masm->build_frame(initial_frame_size_in_bytes(), bang_size_in_bytes());
 779 }
 780 
 781 
 782 void LIR_Assembler::roundfp_op(LIR_Opr src, LIR_Opr tmp, LIR_Opr dest, bool pop_fpu_stack) {
 783   assert((src->is_single_fpu() && dest->is_single_stack()) ||
 784          (src->is_double_fpu() && dest->is_double_stack()),
 785          "round_fp: rounds register -> stack location");
 786 
 787   reg2stack (src, dest, src->type(), pop_fpu_stack);
 788 }
 789 
 790 
 791 void LIR_Assembler::move_op(LIR_Opr src, LIR_Opr dest, BasicType type, LIR_PatchCode patch_code, CodeEmitInfo* info, bool pop_fpu_stack, bool unaligned, bool wide) {
 792   if (src->is_register()) {
 793     if (dest->is_register()) {
 794       assert(patch_code == lir_patch_none && info == NULL, "no patching and info allowed here");
 795       reg2reg(src,  dest);
 796     } else if (dest->is_stack()) {
 797       assert(patch_code == lir_patch_none && info == NULL, "no patching and info allowed here");
 798       reg2stack(src, dest, type, pop_fpu_stack);
 799     } else if (dest->is_address()) {
 800       reg2mem(src, dest, type, patch_code, info, pop_fpu_stack, wide, unaligned);
 801     } else {
 802       ShouldNotReachHere();
 803     }
 804 
 805   } else if (src->is_stack()) {
 806     assert(patch_code == lir_patch_none && info == NULL, "no patching and info allowed here");
 807     if (dest->is_register()) {
 808       stack2reg(src, dest, type);
 809     } else if (dest->is_stack()) {
 810       stack2stack(src, dest, type);
 811     } else {
 812       ShouldNotReachHere();
 813     }
 814 
 815   } else if (src->is_constant()) {
 816     if (dest->is_register()) {
 817       const2reg(src, dest, patch_code, info); // patching is possible
 818     } else if (dest->is_stack()) {
 819       assert(patch_code == lir_patch_none && info == NULL, "no patching and info allowed here");
 820       const2stack(src, dest);
 821     } else if (dest->is_address()) {
 822       assert(patch_code == lir_patch_none, "no patching allowed here");
 823       const2mem(src, dest, type, info, wide);
 824     } else {
 825       ShouldNotReachHere();
 826     }
 827 
 828   } else if (src->is_address()) {
 829     mem2reg(src, dest, type, patch_code, info, wide, unaligned);
 830 
 831   } else {
 832     ShouldNotReachHere();
 833   }
 834 }
 835 
 836 
 837 void LIR_Assembler::verify_oop_map(CodeEmitInfo* info) {
 838 #ifndef PRODUCT
 839   if (VerifyOops) {
 840     OopMapStream s(info->oop_map());
 841     while (!s.is_done()) {
 842       OopMapValue v = s.current();
 843       if (v.is_oop()) {
 844         VMReg r = v.reg();
 845         if (!r->is_stack()) {
 846           stringStream st;
 847           st.print("bad oop %s at %d", r->as_Register()->name(), _masm->offset());
 848 #ifdef SPARC
 849           _masm->_verify_oop(r->as_Register(), os::strdup(st.as_string(), mtCompiler), __FILE__, __LINE__);
 850 #else
 851           _masm->verify_oop(r->as_Register());
 852 #endif
 853         } else {
 854           _masm->verify_stack_oop(r->reg2stack() * VMRegImpl::stack_slot_size);
 855         }
 856       }
 857       check_codespace();
 858       CHECK_BAILOUT();
 859 
 860       s.next();
 861     }
 862   }
 863 #endif
 864 }