1 /*
  2  * Copyright (c) 1999, 2015, 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 "c1/c1_CodeStubs.hpp"
 27 #include "c1/c1_FrameMap.hpp"
 28 #include "c1/c1_LIRAssembler.hpp"
 29 #include "c1/c1_MacroAssembler.hpp"
 30 #include "c1/c1_Runtime1.hpp"
 31 #include "nativeInst_x86.hpp"
 32 #include "runtime/sharedRuntime.hpp"
 33 #include "utilities/align.hpp"
 34 #include "utilities/macros.hpp"
 35 #include "vmreg_x86.inline.hpp"
 36 #if INCLUDE_ALL_GCS
 37 #include "gc/g1/g1SATBCardTableModRefBS.hpp"
 38 #endif // INCLUDE_ALL_GCS
 39 
 40 
 41 #define __ ce->masm()->
 42 
 43 float ConversionStub::float_zero = 0.0;
 44 double ConversionStub::double_zero = 0.0;
 45 
 46 void ConversionStub::emit_code(LIR_Assembler* ce) {
 47   __ bind(_entry);
 48   assert(bytecode() == Bytecodes::_f2i || bytecode() == Bytecodes::_d2i, "other conversions do not require stub");
 49 
 50 
 51   if (input()->is_single_xmm()) {
 52     __ comiss(input()->as_xmm_float_reg(),
 53               ExternalAddress((address)&float_zero));
 54   } else if (input()->is_double_xmm()) {
 55     __ comisd(input()->as_xmm_double_reg(),
 56               ExternalAddress((address)&double_zero));
 57   } else {
 58     LP64_ONLY(ShouldNotReachHere());
 59     __ push(rax);
 60     __ ftst();
 61     __ fnstsw_ax();
 62     __ sahf();
 63     __ pop(rax);
 64   }
 65 
 66   Label NaN, do_return;
 67   __ jccb(Assembler::parity, NaN);
 68   __ jccb(Assembler::below, do_return);
 69 
 70   // input is > 0 -> return maxInt
 71   // result register already contains 0x80000000, so subtracting 1 gives 0x7fffffff
 72   __ decrement(result()->as_register());
 73   __ jmpb(do_return);
 74 
 75   // input is NaN -> return 0
 76   __ bind(NaN);
 77   __ xorptr(result()->as_register(), result()->as_register());
 78 
 79   __ bind(do_return);
 80   __ jmp(_continuation);
 81 }
 82 
 83 void CounterOverflowStub::emit_code(LIR_Assembler* ce) {
 84   __ bind(_entry);
 85   Metadata *m = _method->as_constant_ptr()->as_metadata();
 86   ce->store_parameter(m, 1);
 87   ce->store_parameter(_bci, 0);
 88   __ call(RuntimeAddress(Runtime1::entry_for(Runtime1::counter_overflow_id)));
 89   ce->add_call_info_here(_info);
 90   ce->verify_oop_map(_info);
 91   __ jmp(_continuation);
 92 }
 93 
 94 RangeCheckStub::RangeCheckStub(CodeEmitInfo* info, LIR_Opr index,
 95                                bool throw_index_out_of_bounds_exception)
 96   : _throw_index_out_of_bounds_exception(throw_index_out_of_bounds_exception)
 97   , _index(index)
 98 {
 99   assert(info != NULL, "must have info");
100   _info = new CodeEmitInfo(info);
101 }
102 
103 
104 void RangeCheckStub::emit_code(LIR_Assembler* ce) {
105   __ bind(_entry);
106   if (_info->deoptimize_on_exception()) {
107     address a = Runtime1::entry_for(Runtime1::predicate_failed_trap_id);
108     __ call(RuntimeAddress(a));
109     ce->add_call_info_here(_info);
110     ce->verify_oop_map(_info);
111     debug_only(__ should_not_reach_here());
112     return;
113   }
114 
115   // pass the array index on stack because all registers must be preserved
116   if (_index->is_cpu_register()) {
117     ce->store_parameter(_index->as_register(), 0);
118   } else {
119     ce->store_parameter(_index->as_jint(), 0);
120   }
121   Runtime1::StubID stub_id;
122   if (_throw_index_out_of_bounds_exception) {
123     stub_id = Runtime1::throw_index_exception_id;
124   } else {
125     stub_id = Runtime1::throw_range_check_failed_id;
126   }
127   __ call(RuntimeAddress(Runtime1::entry_for(stub_id)));
128   ce->add_call_info_here(_info);
129   ce->verify_oop_map(_info);
130   debug_only(__ should_not_reach_here());
131 }
132 
133 PredicateFailedStub::PredicateFailedStub(CodeEmitInfo* info) {
134   _info = new CodeEmitInfo(info);
135 }
136 
137 void PredicateFailedStub::emit_code(LIR_Assembler* ce) {
138   __ bind(_entry);
139   address a = Runtime1::entry_for(Runtime1::predicate_failed_trap_id);
140   __ call(RuntimeAddress(a));
141   ce->add_call_info_here(_info);
142   ce->verify_oop_map(_info);
143   debug_only(__ should_not_reach_here());
144 }
145 
146 void DivByZeroStub::emit_code(LIR_Assembler* ce) {
147   if (_offset != -1) {
148     ce->compilation()->implicit_exception_table()->append(_offset, __ offset());
149   }
150   __ bind(_entry);
151   __ call(RuntimeAddress(Runtime1::entry_for(Runtime1::throw_div0_exception_id)));
152   ce->add_call_info_here(_info);
153   debug_only(__ should_not_reach_here());
154 }
155 
156 
157 // Implementation of NewInstanceStub
158 
159 NewInstanceStub::NewInstanceStub(LIR_Opr klass_reg, LIR_Opr result, ciInstanceKlass* klass, CodeEmitInfo* info, Runtime1::StubID stub_id) {
160   _result = result;
161   _klass = klass;
162   _klass_reg = klass_reg;
163   _info = new CodeEmitInfo(info);
164   assert(stub_id == Runtime1::new_instance_id                 ||
165          stub_id == Runtime1::fast_new_instance_id            ||
166          stub_id == Runtime1::fast_new_instance_init_check_id,
167          "need new_instance id");
168   _stub_id   = stub_id;
169 }
170 
171 
172 void NewInstanceStub::emit_code(LIR_Assembler* ce) {
173   assert(__ rsp_offset() == 0, "frame size should be fixed");
174   __ bind(_entry);
175   __ movptr(rdx, _klass_reg->as_register());
176   __ call(RuntimeAddress(Runtime1::entry_for(_stub_id)));
177   ce->add_call_info_here(_info);
178   ce->verify_oop_map(_info);
179   assert(_result->as_register() == rax, "result must in rax,");
180   __ jmp(_continuation);
181 }
182 
183 
184 // Implementation of NewTypeArrayStub
185 
186 NewTypeArrayStub::NewTypeArrayStub(LIR_Opr klass_reg, LIR_Opr length, LIR_Opr result, CodeEmitInfo* info) {
187   _klass_reg = klass_reg;
188   _length = length;
189   _result = result;
190   _info = new CodeEmitInfo(info);
191 }
192 
193 
194 void NewTypeArrayStub::emit_code(LIR_Assembler* ce) {
195   assert(__ rsp_offset() == 0, "frame size should be fixed");
196   __ bind(_entry);
197   assert(_length->as_register() == rbx, "length must in rbx,");
198   assert(_klass_reg->as_register() == rdx, "klass_reg must in rdx");
199   __ call(RuntimeAddress(Runtime1::entry_for(Runtime1::new_type_array_id)));
200   ce->add_call_info_here(_info);
201   ce->verify_oop_map(_info);
202   assert(_result->as_register() == rax, "result must in rax,");
203   __ jmp(_continuation);
204 }
205 
206 
207 // Implementation of NewObjectArrayStub
208 
209 NewObjectArrayStub::NewObjectArrayStub(LIR_Opr klass_reg, LIR_Opr length, LIR_Opr result, CodeEmitInfo* info) {
210   _klass_reg = klass_reg;
211   _result = result;
212   _length = length;
213   _info = new CodeEmitInfo(info);
214 }
215 
216 
217 void NewObjectArrayStub::emit_code(LIR_Assembler* ce) {
218   assert(__ rsp_offset() == 0, "frame size should be fixed");
219   __ bind(_entry);
220   assert(_length->as_register() == rbx, "length must in rbx,");
221   assert(_klass_reg->as_register() == rdx, "klass_reg must in rdx");
222   __ call(RuntimeAddress(Runtime1::entry_for(Runtime1::new_object_array_id)));
223   ce->add_call_info_here(_info);
224   ce->verify_oop_map(_info);
225   assert(_result->as_register() == rax, "result must in rax,");
226   __ jmp(_continuation);
227 }
228 
229 
230 // Implementation of MonitorAccessStubs
231 
232 MonitorEnterStub::MonitorEnterStub(LIR_Opr obj_reg, LIR_Opr lock_reg, CodeEmitInfo* info)
233 : MonitorAccessStub(obj_reg, lock_reg)
234 {
235   _info = new CodeEmitInfo(info);
236 }
237 
238 
239 void MonitorEnterStub::emit_code(LIR_Assembler* ce) {
240   assert(__ rsp_offset() == 0, "frame size should be fixed");
241   __ bind(_entry);
242   ce->store_parameter(_obj_reg->as_register(),  1);
243   ce->store_parameter(_lock_reg->as_register(), 0);
244   Runtime1::StubID enter_id;
245   if (ce->compilation()->has_fpu_code()) {
246     enter_id = Runtime1::monitorenter_id;
247   } else {
248     enter_id = Runtime1::monitorenter_nofpu_id;
249   }
250   __ call(RuntimeAddress(Runtime1::entry_for(enter_id)));
251   ce->add_call_info_here(_info);
252   ce->verify_oop_map(_info);
253   __ jmp(_continuation);
254 }
255 
256 
257 void MonitorExitStub::emit_code(LIR_Assembler* ce) {
258   __ bind(_entry);
259   if (_compute_lock) {
260     // lock_reg was destroyed by fast unlocking attempt => recompute it
261     ce->monitor_address(_monitor_ix, _lock_reg);
262   }
263   ce->store_parameter(_lock_reg->as_register(), 0);
264   // note: non-blocking leaf routine => no call info needed
265   Runtime1::StubID exit_id;
266   if (ce->compilation()->has_fpu_code()) {
267     exit_id = Runtime1::monitorexit_id;
268   } else {
269     exit_id = Runtime1::monitorexit_nofpu_id;
270   }
271   __ call(RuntimeAddress(Runtime1::entry_for(exit_id)));
272   __ jmp(_continuation);
273 }
274 
275 
276 // Implementation of patching:
277 // - Copy the code at given offset to an inlined buffer (first the bytes, then the number of bytes)
278 // - Replace original code with a call to the stub
279 // At Runtime:
280 // - call to stub, jump to runtime
281 // - in runtime: preserve all registers (rspecially objects, i.e., source and destination object)
282 // - in runtime: after initializing class, restore original code, reexecute instruction
283 
284 int PatchingStub::_patch_info_offset = -NativeGeneralJump::instruction_size;
285 
286 void PatchingStub::align_patch_site(MacroAssembler* masm) {
287   // We're patching a 5-7 byte instruction on intel and we need to
288   // make sure that we don't see a piece of the instruction.  It
289   // appears mostly impossible on Intel to simply invalidate other
290   // processors caches and since they may do aggressive prefetch it's
291   // very hard to make a guess about what code might be in the icache.
292   // Force the instruction to be double word aligned so that it
293   // doesn't span a cache line.
294   masm->align(align_up((int)NativeGeneralJump::instruction_size, wordSize));
295 }
296 
297 void PatchingStub::emit_code(LIR_Assembler* ce) {
298   assert(NativeCall::instruction_size <= _bytes_to_copy && _bytes_to_copy <= 0xFF, "not enough room for call");
299 
300   Label call_patch;
301 
302   // static field accesses have special semantics while the class
303   // initializer is being run so we emit a test which can be used to
304   // check that this code is being executed by the initializing
305   // thread.
306   address being_initialized_entry = __ pc();
307   if (CommentedAssembly) {
308     __ block_comment(" patch template");
309   }
310   if (_id == load_klass_id) {
311     // produce a copy of the load klass instruction for use by the being initialized case
312 #ifdef ASSERT
313     address start = __ pc();
314 #endif
315     Metadata* o = NULL;
316     __ mov_metadata(_obj, o);
317 #ifdef ASSERT
318     for (int i = 0; i < _bytes_to_copy; i++) {
319       address ptr = (address)(_pc_start + i);
320       int a_byte = (*ptr) & 0xFF;
321       assert(a_byte == *start++, "should be the same code");
322     }
323 #endif
324   } else if (_id == load_mirror_id) {
325     // produce a copy of the load mirror instruction for use by the being
326     // initialized case
327 #ifdef ASSERT
328     address start = __ pc();
329 #endif
330     jobject o = NULL;
331     __ movoop(_obj, o);
332 #ifdef ASSERT
333     for (int i = 0; i < _bytes_to_copy; i++) {
334       address ptr = (address)(_pc_start + i);
335       int a_byte = (*ptr) & 0xFF;
336       assert(a_byte == *start++, "should be the same code");
337     }
338 #endif
339   } else {
340     // make a copy the code which is going to be patched.
341     for (int i = 0; i < _bytes_to_copy; i++) {
342       address ptr = (address)(_pc_start + i);
343       int a_byte = (*ptr) & 0xFF;
344       __ emit_int8(a_byte);
345       *ptr = 0x90; // make the site look like a nop
346     }
347   }
348 
349   address end_of_patch = __ pc();
350   int bytes_to_skip = 0;
351   if (_id == load_mirror_id) {
352     int offset = __ offset();
353     if (CommentedAssembly) {
354       __ block_comment(" being_initialized check");
355     }
356     assert(_obj != noreg, "must be a valid register");
357     Register tmp = rax;
358     Register tmp2 = rbx;
359     __ push(tmp);
360     __ push(tmp2);
361     // Load without verification to keep code size small. We need it because
362     // begin_initialized_entry_offset has to fit in a byte. Also, we know it's not null.
363     __ movptr(tmp2, Address(_obj, java_lang_Class::klass_offset_in_bytes()));
364     __ get_thread(tmp);
365     __ cmpptr(tmp, Address(tmp2, InstanceKlass::init_thread_offset()));
366     __ pop(tmp2);
367     __ pop(tmp);
368     __ jcc(Assembler::notEqual, call_patch);
369 
370     // access_field patches may execute the patched code before it's
371     // copied back into place so we need to jump back into the main
372     // code of the nmethod to continue execution.
373     __ jmp(_patch_site_continuation);
374 
375     // make sure this extra code gets skipped
376     bytes_to_skip += __ offset() - offset;
377   }
378   if (CommentedAssembly) {
379     __ block_comment("patch data encoded as movl");
380   }
381   // Now emit the patch record telling the runtime how to find the
382   // pieces of the patch.  We only need 3 bytes but for readability of
383   // the disassembly we make the data look like a movl reg, imm32,
384   // which requires 5 bytes
385   int sizeof_patch_record = 5;
386   bytes_to_skip += sizeof_patch_record;
387 
388   // emit the offsets needed to find the code to patch
389   int being_initialized_entry_offset = __ pc() - being_initialized_entry + sizeof_patch_record;
390 
391   __ emit_int8((unsigned char)0xB8);
392   __ emit_int8(0);
393   __ emit_int8(being_initialized_entry_offset);
394   __ emit_int8(bytes_to_skip);
395   __ emit_int8(_bytes_to_copy);
396   address patch_info_pc = __ pc();
397   assert(patch_info_pc - end_of_patch == bytes_to_skip, "incorrect patch info");
398 
399   address entry = __ pc();
400   NativeGeneralJump::insert_unconditional((address)_pc_start, entry);
401   address target = NULL;
402   relocInfo::relocType reloc_type = relocInfo::none;
403   switch (_id) {
404     case access_field_id:  target = Runtime1::entry_for(Runtime1::access_field_patching_id); break;
405     case load_klass_id:    target = Runtime1::entry_for(Runtime1::load_klass_patching_id); reloc_type = relocInfo::metadata_type; break;
406     case load_mirror_id:   target = Runtime1::entry_for(Runtime1::load_mirror_patching_id); reloc_type = relocInfo::oop_type; break;
407     case load_appendix_id:      target = Runtime1::entry_for(Runtime1::load_appendix_patching_id); reloc_type = relocInfo::oop_type; break;
408     default: ShouldNotReachHere();
409   }
410   __ bind(call_patch);
411 
412   if (CommentedAssembly) {
413     __ block_comment("patch entry point");
414   }
415   __ call(RuntimeAddress(target));
416   assert(_patch_info_offset == (patch_info_pc - __ pc()), "must not change");
417   ce->add_call_info_here(_info);
418   int jmp_off = __ offset();
419   __ jmp(_patch_site_entry);
420   // Add enough nops so deoptimization can overwrite the jmp above with a call
421   // and not destroy the world. We cannot use fat nops here, since the concurrent
422   // code rewrite may transiently create the illegal instruction sequence.
423   for (int j = __ offset() ; j < jmp_off + 5 ; j++ ) {
424     __ nop();
425   }
426   if (_id == load_klass_id || _id == load_mirror_id || _id == load_appendix_id) {
427     CodeSection* cs = __ code_section();
428     RelocIterator iter(cs, (address)_pc_start, (address)(_pc_start + 1));
429     relocInfo::change_reloc_info_for_address(&iter, (address) _pc_start, reloc_type, relocInfo::none);
430   }
431 }
432 
433 
434 void DeoptimizeStub::emit_code(LIR_Assembler* ce) {
435   __ bind(_entry);
436   ce->store_parameter(_trap_request, 0);
437   __ call(RuntimeAddress(Runtime1::entry_for(Runtime1::deoptimize_id)));
438   ce->add_call_info_here(_info);
439   DEBUG_ONLY(__ should_not_reach_here());
440 }
441 
442 
443 void ImplicitNullCheckStub::emit_code(LIR_Assembler* ce) {
444   address a;
445   if (_info->deoptimize_on_exception()) {
446     // Deoptimize, do not throw the exception, because it is probably wrong to do it here.
447     a = Runtime1::entry_for(Runtime1::predicate_failed_trap_id);
448   } else {
449     a = Runtime1::entry_for(Runtime1::throw_null_pointer_exception_id);
450   }
451 
452   ce->compilation()->implicit_exception_table()->append(_offset, __ offset());
453   __ bind(_entry);
454   __ call(RuntimeAddress(a));
455   ce->add_call_info_here(_info);
456   ce->verify_oop_map(_info);
457   debug_only(__ should_not_reach_here());
458 }
459 
460 
461 void SimpleExceptionStub::emit_code(LIR_Assembler* ce) {
462   assert(__ rsp_offset() == 0, "frame size should be fixed");
463 
464   __ bind(_entry);
465   // pass the object on stack because all registers must be preserved
466   if (_obj->is_cpu_register()) {
467     ce->store_parameter(_obj->as_register(), 0);
468   }
469   __ call(RuntimeAddress(Runtime1::entry_for(_stub)));
470   ce->add_call_info_here(_info);
471   debug_only(__ should_not_reach_here());
472 }
473 
474 
475 void ArrayCopyStub::emit_code(LIR_Assembler* ce) {
476   //---------------slow case: call to native-----------------
477   __ bind(_entry);
478   // Figure out where the args should go
479   // This should really convert the IntrinsicID to the Method* and signature
480   // but I don't know how to do that.
481   //
482   VMRegPair args[5];
483   BasicType signature[5] = { T_OBJECT, T_INT, T_OBJECT, T_INT, T_INT};
484   SharedRuntime::java_calling_convention(signature, args, 5, true);
485 
486   // push parameters
487   // (src, src_pos, dest, destPos, length)
488   Register r[5];
489   r[0] = src()->as_register();
490   r[1] = src_pos()->as_register();
491   r[2] = dst()->as_register();
492   r[3] = dst_pos()->as_register();
493   r[4] = length()->as_register();
494 
495   // next registers will get stored on the stack
496   for (int i = 0; i < 5 ; i++ ) {
497     VMReg r_1 = args[i].first();
498     if (r_1->is_stack()) {
499       int st_off = r_1->reg2stack() * wordSize;
500       __ movptr (Address(rsp, st_off), r[i]);
501     } else {
502       assert(r[i] == args[i].first()->as_Register(), "Wrong register for arg ");
503     }
504   }
505 
506   ce->align_call(lir_static_call);
507 
508   ce->emit_static_call_stub();
509   if (ce->compilation()->bailed_out()) {
510     return; // CodeCache is full
511   }
512   AddressLiteral resolve(SharedRuntime::get_resolve_static_call_stub(),
513                          relocInfo::static_call_type);
514   __ call(resolve);
515   ce->add_call_info_here(info());
516 
517 #ifndef PRODUCT
518   __ incrementl(ExternalAddress((address)&Runtime1::_arraycopy_slowcase_cnt));
519 #endif
520 
521   __ jmp(_continuation);
522 }
523 
524 /////////////////////////////////////////////////////////////////////////////
525 #if INCLUDE_ALL_GCS
526 
527 void G1PreBarrierStub::emit_code(LIR_Assembler* ce) {
528   // At this point we know that marking is in progress.
529   // If do_load() is true then we have to emit the
530   // load of the previous value; otherwise it has already
531   // been loaded into _pre_val.
532 
533   __ bind(_entry);
534   assert(pre_val()->is_register(), "Precondition.");
535 
536   Register pre_val_reg = pre_val()->as_register();
537 
538   if (do_load()) {
539     ce->mem2reg(addr(), pre_val(), T_OBJECT, patch_code(), info(), false /*wide*/, false /*unaligned*/);
540   }
541 
542   __ cmpptr(pre_val_reg, (int32_t) NULL_WORD);
543   __ jcc(Assembler::equal, _continuation);
544   ce->store_parameter(pre_val()->as_register(), 0);
545   __ call(RuntimeAddress(Runtime1::entry_for(Runtime1::g1_pre_barrier_slow_id)));
546   __ jmp(_continuation);
547 
548 }
549 
550 void G1PostBarrierStub::emit_code(LIR_Assembler* ce) {
551   __ bind(_entry);
552   assert(addr()->is_register(), "Precondition.");
553   assert(new_val()->is_register(), "Precondition.");
554   Register new_val_reg = new_val()->as_register();
555   __ cmpptr(new_val_reg, (int32_t) NULL_WORD);
556   __ jcc(Assembler::equal, _continuation);
557   ce->store_parameter(addr()->as_pointer_register(), 0);
558   __ call(RuntimeAddress(Runtime1::entry_for(Runtime1::g1_post_barrier_slow_id)));
559   __ jmp(_continuation);
560 }
561 
562 #endif // INCLUDE_ALL_GCS
563 /////////////////////////////////////////////////////////////////////////////
564 
565 #undef __