1 /*
2  * Copyright (C) 2012 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "art_method-inl.h"
18 #include "base/callee_save_type.h"
19 #include "base/enums.h"
20 #include "callee_save_frame.h"
21 #include "common_throws.h"
22 #include "class_root.h"
23 #include "debug_print.h"
24 #include "debugger.h"
25 #include "dex/dex_file-inl.h"
26 #include "dex/dex_file_types.h"
27 #include "dex/dex_instruction-inl.h"
28 #include "dex/method_reference.h"
29 #include "entrypoints/entrypoint_utils-inl.h"
30 #include "entrypoints/quick/callee_save_frame.h"
31 #include "entrypoints/runtime_asm_entrypoints.h"
32 #include "gc/accounting/card_table-inl.h"
33 #include "imt_conflict_table.h"
34 #include "imtable-inl.h"
35 #include "index_bss_mapping.h"
36 #include "instrumentation.h"
37 #include "interpreter/interpreter.h"
38 #include "interpreter/interpreter_common.h"
39 #include "interpreter/shadow_frame-inl.h"
40 #include "jit/jit.h"
41 #include "jit/jit_code_cache.h"
42 #include "linear_alloc.h"
43 #include "method_handles.h"
44 #include "mirror/class-inl.h"
45 #include "mirror/dex_cache-inl.h"
46 #include "mirror/method.h"
47 #include "mirror/method_handle_impl.h"
48 #include "mirror/object-inl.h"
49 #include "mirror/object_array-inl.h"
50 #include "mirror/var_handle.h"
51 #include "oat.h"
52 #include "oat_file.h"
53 #include "oat_quick_method_header.h"
54 #include "quick_exception_handler.h"
55 #include "runtime.h"
56 #include "scoped_thread_state_change-inl.h"
57 #include "stack.h"
58 #include "thread-inl.h"
59 #include "var_handles.h"
60 #include "well_known_classes.h"
61 
62 namespace art {
63 
64 // Visits the arguments as saved to the stack by a CalleeSaveType::kRefAndArgs callee save frame.
65 class QuickArgumentVisitor {
66   // Number of bytes for each out register in the caller method's frame.
67   static constexpr size_t kBytesStackArgLocation = 4;
68   // Frame size in bytes of a callee-save frame for RefsAndArgs.
69   static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_FrameSize =
70       RuntimeCalleeSaveFrame::GetFrameSize(CalleeSaveType::kSaveRefsAndArgs);
71   // Offset of first GPR arg.
72   static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_Gpr1Offset =
73       RuntimeCalleeSaveFrame::GetGpr1Offset(CalleeSaveType::kSaveRefsAndArgs);
74   // Offset of first FPR arg.
75   static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_Fpr1Offset =
76       RuntimeCalleeSaveFrame::GetFpr1Offset(CalleeSaveType::kSaveRefsAndArgs);
77   // Offset of return address.
78   static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_ReturnPcOffset =
79       RuntimeCalleeSaveFrame::GetReturnPcOffset(CalleeSaveType::kSaveRefsAndArgs);
80 #if defined(__arm__)
81   // The callee save frame is pointed to by SP.
82   // | argN       |  |
83   // | ...        |  |
84   // | arg4       |  |
85   // | arg3 spill |  |  Caller's frame
86   // | arg2 spill |  |
87   // | arg1 spill |  |
88   // | Method*    | ---
89   // | LR         |
90   // | ...        |    4x6 bytes callee saves
91   // | R3         |
92   // | R2         |
93   // | R1         |
94   // | S15        |
95   // | :          |
96   // | S0         |
97   // |            |    4x2 bytes padding
98   // | Method*    |  <- sp
99   static constexpr bool kSplitPairAcrossRegisterAndStack = false;
100   static constexpr bool kAlignPairRegister = true;
101   static constexpr bool kQuickSoftFloatAbi = false;
102   static constexpr bool kQuickDoubleRegAlignedFloatBackFilled = true;
103   static constexpr bool kQuickSkipOddFpRegisters = false;
104   static constexpr size_t kNumQuickGprArgs = 3;
105   static constexpr size_t kNumQuickFprArgs = 16;
106   static constexpr bool kGprFprLockstep = false;
GprIndexToGprOffset(uint32_t gpr_index)107   static size_t GprIndexToGprOffset(uint32_t gpr_index) {
108     return gpr_index * GetBytesPerGprSpillLocation(kRuntimeISA);
109   }
110 #elif defined(__aarch64__)
111   // The callee save frame is pointed to by SP.
112   // | argN       |  |
113   // | ...        |  |
114   // | arg4       |  |
115   // | arg3 spill |  |  Caller's frame
116   // | arg2 spill |  |
117   // | arg1 spill |  |
118   // | Method*    | ---
119   // | LR         |
120   // | X29        |
121   // |  :         |
122   // | X20        |
123   // | X7         |
124   // | :          |
125   // | X1         |
126   // | D7         |
127   // |  :         |
128   // | D0         |
129   // |            |    padding
130   // | Method*    |  <- sp
131   static constexpr bool kSplitPairAcrossRegisterAndStack = false;
132   static constexpr bool kAlignPairRegister = false;
133   static constexpr bool kQuickSoftFloatAbi = false;  // This is a hard float ABI.
134   static constexpr bool kQuickDoubleRegAlignedFloatBackFilled = false;
135   static constexpr bool kQuickSkipOddFpRegisters = false;
136   static constexpr size_t kNumQuickGprArgs = 7;  // 7 arguments passed in GPRs.
137   static constexpr size_t kNumQuickFprArgs = 8;  // 8 arguments passed in FPRs.
138   static constexpr bool kGprFprLockstep = false;
GprIndexToGprOffset(uint32_t gpr_index)139   static size_t GprIndexToGprOffset(uint32_t gpr_index) {
140     return gpr_index * GetBytesPerGprSpillLocation(kRuntimeISA);
141   }
142 #elif defined(__i386__)
143   // The callee save frame is pointed to by SP.
144   // | argN        |  |
145   // | ...         |  |
146   // | arg4        |  |
147   // | arg3 spill  |  |  Caller's frame
148   // | arg2 spill  |  |
149   // | arg1 spill  |  |
150   // | Method*     | ---
151   // | Return      |
152   // | EBP,ESI,EDI |    callee saves
153   // | EBX         |    arg3
154   // | EDX         |    arg2
155   // | ECX         |    arg1
156   // | XMM3        |    float arg 4
157   // | XMM2        |    float arg 3
158   // | XMM1        |    float arg 2
159   // | XMM0        |    float arg 1
160   // | EAX/Method* |  <- sp
161   static constexpr bool kSplitPairAcrossRegisterAndStack = false;
162   static constexpr bool kAlignPairRegister = false;
163   static constexpr bool kQuickSoftFloatAbi = false;  // This is a hard float ABI.
164   static constexpr bool kQuickDoubleRegAlignedFloatBackFilled = false;
165   static constexpr bool kQuickSkipOddFpRegisters = false;
166   static constexpr size_t kNumQuickGprArgs = 3;  // 3 arguments passed in GPRs.
167   static constexpr size_t kNumQuickFprArgs = 4;  // 4 arguments passed in FPRs.
168   static constexpr bool kGprFprLockstep = false;
GprIndexToGprOffset(uint32_t gpr_index)169   static size_t GprIndexToGprOffset(uint32_t gpr_index) {
170     return gpr_index * GetBytesPerGprSpillLocation(kRuntimeISA);
171   }
172 #elif defined(__x86_64__)
173   // The callee save frame is pointed to by SP.
174   // | argN            |  |
175   // | ...             |  |
176   // | reg. arg spills |  |  Caller's frame
177   // | Method*         | ---
178   // | Return          |
179   // | R15             |    callee save
180   // | R14             |    callee save
181   // | R13             |    callee save
182   // | R12             |    callee save
183   // | R9              |    arg5
184   // | R8              |    arg4
185   // | RSI/R6          |    arg1
186   // | RBP/R5          |    callee save
187   // | RBX/R3          |    callee save
188   // | RDX/R2          |    arg2
189   // | RCX/R1          |    arg3
190   // | XMM7            |    float arg 8
191   // | XMM6            |    float arg 7
192   // | XMM5            |    float arg 6
193   // | XMM4            |    float arg 5
194   // | XMM3            |    float arg 4
195   // | XMM2            |    float arg 3
196   // | XMM1            |    float arg 2
197   // | XMM0            |    float arg 1
198   // | Padding         |
199   // | RDI/Method*     |  <- sp
200   static constexpr bool kSplitPairAcrossRegisterAndStack = false;
201   static constexpr bool kAlignPairRegister = false;
202   static constexpr bool kQuickSoftFloatAbi = false;  // This is a hard float ABI.
203   static constexpr bool kQuickDoubleRegAlignedFloatBackFilled = false;
204   static constexpr bool kQuickSkipOddFpRegisters = false;
205   static constexpr size_t kNumQuickGprArgs = 5;  // 5 arguments passed in GPRs.
206   static constexpr size_t kNumQuickFprArgs = 8;  // 8 arguments passed in FPRs.
207   static constexpr bool kGprFprLockstep = false;
GprIndexToGprOffset(uint32_t gpr_index)208   static size_t GprIndexToGprOffset(uint32_t gpr_index) {
209     switch (gpr_index) {
210       case 0: return (4 * GetBytesPerGprSpillLocation(kRuntimeISA));
211       case 1: return (1 * GetBytesPerGprSpillLocation(kRuntimeISA));
212       case 2: return (0 * GetBytesPerGprSpillLocation(kRuntimeISA));
213       case 3: return (5 * GetBytesPerGprSpillLocation(kRuntimeISA));
214       case 4: return (6 * GetBytesPerGprSpillLocation(kRuntimeISA));
215       default:
216       LOG(FATAL) << "Unexpected GPR index: " << gpr_index;
217       UNREACHABLE();
218     }
219   }
220 #else
221 #error "Unsupported architecture"
222 #endif
223 
224  public:
225   // Special handling for proxy methods. Proxy methods are instance methods so the
226   // 'this' object is the 1st argument. They also have the same frame layout as the
227   // kRefAndArgs runtime method. Since 'this' is a reference, it is located in the
228   // 1st GPR.
GetProxyThisObjectReference(ArtMethod ** sp)229   static StackReference<mirror::Object>* GetProxyThisObjectReference(ArtMethod** sp)
230       REQUIRES_SHARED(Locks::mutator_lock_) {
231     CHECK((*sp)->IsProxyMethod());
232     CHECK_GT(kNumQuickGprArgs, 0u);
233     constexpr uint32_t kThisGprIndex = 0u;  // 'this' is in the 1st GPR.
234     size_t this_arg_offset = kQuickCalleeSaveFrame_RefAndArgs_Gpr1Offset +
235         GprIndexToGprOffset(kThisGprIndex);
236     uint8_t* this_arg_address = reinterpret_cast<uint8_t*>(sp) + this_arg_offset;
237     return reinterpret_cast<StackReference<mirror::Object>*>(this_arg_address);
238   }
239 
GetCallingMethod(ArtMethod ** sp)240   static ArtMethod* GetCallingMethod(ArtMethod** sp) REQUIRES_SHARED(Locks::mutator_lock_) {
241     DCHECK((*sp)->IsCalleeSaveMethod());
242     return GetCalleeSaveMethodCaller(sp, CalleeSaveType::kSaveRefsAndArgs);
243   }
244 
GetOuterMethod(ArtMethod ** sp)245   static ArtMethod* GetOuterMethod(ArtMethod** sp) REQUIRES_SHARED(Locks::mutator_lock_) {
246     DCHECK((*sp)->IsCalleeSaveMethod());
247     uint8_t* previous_sp =
248         reinterpret_cast<uint8_t*>(sp) + kQuickCalleeSaveFrame_RefAndArgs_FrameSize;
249     return *reinterpret_cast<ArtMethod**>(previous_sp);
250   }
251 
GetCallingDexPc(ArtMethod ** sp)252   static uint32_t GetCallingDexPc(ArtMethod** sp) REQUIRES_SHARED(Locks::mutator_lock_) {
253     DCHECK((*sp)->IsCalleeSaveMethod());
254     constexpr size_t callee_frame_size =
255         RuntimeCalleeSaveFrame::GetFrameSize(CalleeSaveType::kSaveRefsAndArgs);
256     ArtMethod** caller_sp = reinterpret_cast<ArtMethod**>(
257         reinterpret_cast<uintptr_t>(sp) + callee_frame_size);
258     uintptr_t outer_pc = QuickArgumentVisitor::GetCallingPc(sp);
259     const OatQuickMethodHeader* current_code = (*caller_sp)->GetOatQuickMethodHeader(outer_pc);
260     uintptr_t outer_pc_offset = current_code->NativeQuickPcOffset(outer_pc);
261 
262     if (current_code->IsOptimized()) {
263       CodeInfo code_info = CodeInfo::DecodeInlineInfoOnly(current_code);
264       StackMap stack_map = code_info.GetStackMapForNativePcOffset(outer_pc_offset);
265       DCHECK(stack_map.IsValid());
266       BitTableRange<InlineInfo> inline_infos = code_info.GetInlineInfosOf(stack_map);
267       if (!inline_infos.empty()) {
268         return inline_infos.back().GetDexPc();
269       } else {
270         return stack_map.GetDexPc();
271       }
272     } else {
273       return current_code->ToDexPc(caller_sp, outer_pc);
274     }
275   }
276 
GetCallingPcAddr(ArtMethod ** sp)277   static uint8_t* GetCallingPcAddr(ArtMethod** sp) REQUIRES_SHARED(Locks::mutator_lock_) {
278     DCHECK((*sp)->IsCalleeSaveMethod());
279     uint8_t* return_adress_spill =
280         reinterpret_cast<uint8_t*>(sp) + kQuickCalleeSaveFrame_RefAndArgs_ReturnPcOffset;
281     return return_adress_spill;
282   }
283 
284   // For the given quick ref and args quick frame, return the caller's PC.
GetCallingPc(ArtMethod ** sp)285   static uintptr_t GetCallingPc(ArtMethod** sp) REQUIRES_SHARED(Locks::mutator_lock_) {
286     return *reinterpret_cast<uintptr_t*>(GetCallingPcAddr(sp));
287   }
288 
QuickArgumentVisitor(ArtMethod ** sp,bool is_static,const char * shorty,uint32_t shorty_len)289   QuickArgumentVisitor(ArtMethod** sp, bool is_static, const char* shorty,
290                        uint32_t shorty_len) REQUIRES_SHARED(Locks::mutator_lock_) :
291           is_static_(is_static), shorty_(shorty), shorty_len_(shorty_len),
292           gpr_args_(reinterpret_cast<uint8_t*>(sp) + kQuickCalleeSaveFrame_RefAndArgs_Gpr1Offset),
293           fpr_args_(reinterpret_cast<uint8_t*>(sp) + kQuickCalleeSaveFrame_RefAndArgs_Fpr1Offset),
294           stack_args_(reinterpret_cast<uint8_t*>(sp) + kQuickCalleeSaveFrame_RefAndArgs_FrameSize
295               + sizeof(ArtMethod*)),  // Skip ArtMethod*.
296           gpr_index_(0), fpr_index_(0), fpr_double_index_(0), stack_index_(0),
297           cur_type_(Primitive::kPrimVoid), is_split_long_or_double_(false) {
298     static_assert(kQuickSoftFloatAbi == (kNumQuickFprArgs == 0),
299                   "Number of Quick FPR arguments unexpected");
300     static_assert(!(kQuickSoftFloatAbi && kQuickDoubleRegAlignedFloatBackFilled),
301                   "Double alignment unexpected");
302     // For register alignment, we want to assume that counters(fpr_double_index_) are even if the
303     // next register is even.
304     static_assert(!kQuickDoubleRegAlignedFloatBackFilled || kNumQuickFprArgs % 2 == 0,
305                   "Number of Quick FPR arguments not even");
306     DCHECK_EQ(Runtime::Current()->GetClassLinker()->GetImagePointerSize(), kRuntimePointerSize);
307   }
308 
~QuickArgumentVisitor()309   virtual ~QuickArgumentVisitor() {}
310 
311   virtual void Visit() = 0;
312 
GetParamPrimitiveType() const313   Primitive::Type GetParamPrimitiveType() const {
314     return cur_type_;
315   }
316 
GetParamAddress() const317   uint8_t* GetParamAddress() const {
318     if (!kQuickSoftFloatAbi) {
319       Primitive::Type type = GetParamPrimitiveType();
320       if (UNLIKELY((type == Primitive::kPrimDouble) || (type == Primitive::kPrimFloat))) {
321         if (type == Primitive::kPrimDouble && kQuickDoubleRegAlignedFloatBackFilled) {
322           if (fpr_double_index_ + 2 < kNumQuickFprArgs + 1) {
323             return fpr_args_ + (fpr_double_index_ * GetBytesPerFprSpillLocation(kRuntimeISA));
324           }
325         } else if (fpr_index_ + 1 < kNumQuickFprArgs + 1) {
326           return fpr_args_ + (fpr_index_ * GetBytesPerFprSpillLocation(kRuntimeISA));
327         }
328         return stack_args_ + (stack_index_ * kBytesStackArgLocation);
329       }
330     }
331     if (gpr_index_ < kNumQuickGprArgs) {
332       return gpr_args_ + GprIndexToGprOffset(gpr_index_);
333     }
334     return stack_args_ + (stack_index_ * kBytesStackArgLocation);
335   }
336 
IsSplitLongOrDouble() const337   bool IsSplitLongOrDouble() const {
338     if ((GetBytesPerGprSpillLocation(kRuntimeISA) == 4) ||
339         (GetBytesPerFprSpillLocation(kRuntimeISA) == 4)) {
340       return is_split_long_or_double_;
341     } else {
342       return false;  // An optimization for when GPR and FPRs are 64bit.
343     }
344   }
345 
IsParamAReference() const346   bool IsParamAReference() const {
347     return GetParamPrimitiveType() == Primitive::kPrimNot;
348   }
349 
IsParamALongOrDouble() const350   bool IsParamALongOrDouble() const {
351     Primitive::Type type = GetParamPrimitiveType();
352     return type == Primitive::kPrimLong || type == Primitive::kPrimDouble;
353   }
354 
ReadSplitLongParam() const355   uint64_t ReadSplitLongParam() const {
356     // The splitted long is always available through the stack.
357     return *reinterpret_cast<uint64_t*>(stack_args_
358         + stack_index_ * kBytesStackArgLocation);
359   }
360 
IncGprIndex()361   void IncGprIndex() {
362     gpr_index_++;
363     if (kGprFprLockstep) {
364       fpr_index_++;
365     }
366   }
367 
IncFprIndex()368   void IncFprIndex() {
369     fpr_index_++;
370     if (kGprFprLockstep) {
371       gpr_index_++;
372     }
373   }
374 
VisitArguments()375   void VisitArguments() REQUIRES_SHARED(Locks::mutator_lock_) {
376     // (a) 'stack_args_' should point to the first method's argument
377     // (b) whatever the argument type it is, the 'stack_index_' should
378     //     be moved forward along with every visiting.
379     gpr_index_ = 0;
380     fpr_index_ = 0;
381     if (kQuickDoubleRegAlignedFloatBackFilled) {
382       fpr_double_index_ = 0;
383     }
384     stack_index_ = 0;
385     if (!is_static_) {  // Handle this.
386       cur_type_ = Primitive::kPrimNot;
387       is_split_long_or_double_ = false;
388       Visit();
389       stack_index_++;
390       if (kNumQuickGprArgs > 0) {
391         IncGprIndex();
392       }
393     }
394     for (uint32_t shorty_index = 1; shorty_index < shorty_len_; ++shorty_index) {
395       cur_type_ = Primitive::GetType(shorty_[shorty_index]);
396       switch (cur_type_) {
397         case Primitive::kPrimNot:
398         case Primitive::kPrimBoolean:
399         case Primitive::kPrimByte:
400         case Primitive::kPrimChar:
401         case Primitive::kPrimShort:
402         case Primitive::kPrimInt:
403           is_split_long_or_double_ = false;
404           Visit();
405           stack_index_++;
406           if (gpr_index_ < kNumQuickGprArgs) {
407             IncGprIndex();
408           }
409           break;
410         case Primitive::kPrimFloat:
411           is_split_long_or_double_ = false;
412           Visit();
413           stack_index_++;
414           if (kQuickSoftFloatAbi) {
415             if (gpr_index_ < kNumQuickGprArgs) {
416               IncGprIndex();
417             }
418           } else {
419             if (fpr_index_ + 1 < kNumQuickFprArgs + 1) {
420               IncFprIndex();
421               if (kQuickDoubleRegAlignedFloatBackFilled) {
422                 // Double should not overlap with float.
423                 // For example, if fpr_index_ = 3, fpr_double_index_ should be at least 4.
424                 fpr_double_index_ = std::max(fpr_double_index_, RoundUp(fpr_index_, 2));
425                 // Float should not overlap with double.
426                 if (fpr_index_ % 2 == 0) {
427                   fpr_index_ = std::max(fpr_double_index_, fpr_index_);
428                 }
429               } else if (kQuickSkipOddFpRegisters) {
430                 IncFprIndex();
431               }
432             }
433           }
434           break;
435         case Primitive::kPrimDouble:
436         case Primitive::kPrimLong:
437           if (kQuickSoftFloatAbi || (cur_type_ == Primitive::kPrimLong)) {
438             if (cur_type_ == Primitive::kPrimLong &&
439                 gpr_index_ == 0 &&
440                 kAlignPairRegister) {
441               // Currently, this is only for ARM, where we align long parameters with
442               // even-numbered registers by skipping R1 and using R2 instead.
443               IncGprIndex();
444             }
445             is_split_long_or_double_ = (GetBytesPerGprSpillLocation(kRuntimeISA) == 4) &&
446                 ((gpr_index_ + 1) == kNumQuickGprArgs);
447             if (!kSplitPairAcrossRegisterAndStack && is_split_long_or_double_) {
448               // We don't want to split this. Pass over this register.
449               gpr_index_++;
450               is_split_long_or_double_ = false;
451             }
452             Visit();
453             if (kBytesStackArgLocation == 4) {
454               stack_index_+= 2;
455             } else {
456               CHECK_EQ(kBytesStackArgLocation, 8U);
457               stack_index_++;
458             }
459             if (gpr_index_ < kNumQuickGprArgs) {
460               IncGprIndex();
461               if (GetBytesPerGprSpillLocation(kRuntimeISA) == 4) {
462                 if (gpr_index_ < kNumQuickGprArgs) {
463                   IncGprIndex();
464                 }
465               }
466             }
467           } else {
468             is_split_long_or_double_ = (GetBytesPerFprSpillLocation(kRuntimeISA) == 4) &&
469                 ((fpr_index_ + 1) == kNumQuickFprArgs) && !kQuickDoubleRegAlignedFloatBackFilled;
470             Visit();
471             if (kBytesStackArgLocation == 4) {
472               stack_index_+= 2;
473             } else {
474               CHECK_EQ(kBytesStackArgLocation, 8U);
475               stack_index_++;
476             }
477             if (kQuickDoubleRegAlignedFloatBackFilled) {
478               if (fpr_double_index_ + 2 < kNumQuickFprArgs + 1) {
479                 fpr_double_index_ += 2;
480                 // Float should not overlap with double.
481                 if (fpr_index_ % 2 == 0) {
482                   fpr_index_ = std::max(fpr_double_index_, fpr_index_);
483                 }
484               }
485             } else if (fpr_index_ + 1 < kNumQuickFprArgs + 1) {
486               IncFprIndex();
487               if (GetBytesPerFprSpillLocation(kRuntimeISA) == 4) {
488                 if (fpr_index_ + 1 < kNumQuickFprArgs + 1) {
489                   IncFprIndex();
490                 }
491               }
492             }
493           }
494           break;
495         default:
496           LOG(FATAL) << "Unexpected type: " << cur_type_ << " in " << shorty_;
497       }
498     }
499   }
500 
501  protected:
502   const bool is_static_;
503   const char* const shorty_;
504   const uint32_t shorty_len_;
505 
506  private:
507   uint8_t* const gpr_args_;  // Address of GPR arguments in callee save frame.
508   uint8_t* const fpr_args_;  // Address of FPR arguments in callee save frame.
509   uint8_t* const stack_args_;  // Address of stack arguments in caller's frame.
510   uint32_t gpr_index_;  // Index into spilled GPRs.
511   // Index into spilled FPRs.
512   // In case kQuickDoubleRegAlignedFloatBackFilled, it may index a hole while fpr_double_index_
513   // holds a higher register number.
514   uint32_t fpr_index_;
515   // Index into spilled FPRs for aligned double.
516   // Only used when kQuickDoubleRegAlignedFloatBackFilled. Next available double register indexed in
517   // terms of singles, may be behind fpr_index.
518   uint32_t fpr_double_index_;
519   uint32_t stack_index_;  // Index into arguments on the stack.
520   // The current type of argument during VisitArguments.
521   Primitive::Type cur_type_;
522   // Does a 64bit parameter straddle the register and stack arguments?
523   bool is_split_long_or_double_;
524 };
525 
526 // Returns the 'this' object of a proxy method. This function is only used by StackVisitor. It
527 // allows to use the QuickArgumentVisitor constants without moving all the code in its own module.
artQuickGetProxyThisObject(ArtMethod ** sp)528 extern "C" mirror::Object* artQuickGetProxyThisObject(ArtMethod** sp)
529     REQUIRES_SHARED(Locks::mutator_lock_) {
530   return QuickArgumentVisitor::GetProxyThisObjectReference(sp)->AsMirrorPtr();
531 }
532 
533 // Visits arguments on the stack placing them into the shadow frame.
534 class BuildQuickShadowFrameVisitor final : public QuickArgumentVisitor {
535  public:
BuildQuickShadowFrameVisitor(ArtMethod ** sp,bool is_static,const char * shorty,uint32_t shorty_len,ShadowFrame * sf,size_t first_arg_reg)536   BuildQuickShadowFrameVisitor(ArtMethod** sp, bool is_static, const char* shorty,
537                                uint32_t shorty_len, ShadowFrame* sf, size_t first_arg_reg) :
538       QuickArgumentVisitor(sp, is_static, shorty, shorty_len), sf_(sf), cur_reg_(first_arg_reg) {}
539 
540   void Visit() REQUIRES_SHARED(Locks::mutator_lock_) override;
541 
542  private:
543   ShadowFrame* const sf_;
544   uint32_t cur_reg_;
545 
546   DISALLOW_COPY_AND_ASSIGN(BuildQuickShadowFrameVisitor);
547 };
548 
Visit()549 void BuildQuickShadowFrameVisitor::Visit() {
550   Primitive::Type type = GetParamPrimitiveType();
551   switch (type) {
552     case Primitive::kPrimLong:  // Fall-through.
553     case Primitive::kPrimDouble:
554       if (IsSplitLongOrDouble()) {
555         sf_->SetVRegLong(cur_reg_, ReadSplitLongParam());
556       } else {
557         sf_->SetVRegLong(cur_reg_, *reinterpret_cast<jlong*>(GetParamAddress()));
558       }
559       ++cur_reg_;
560       break;
561     case Primitive::kPrimNot: {
562         StackReference<mirror::Object>* stack_ref =
563             reinterpret_cast<StackReference<mirror::Object>*>(GetParamAddress());
564         sf_->SetVRegReference(cur_reg_, stack_ref->AsMirrorPtr());
565       }
566       break;
567     case Primitive::kPrimBoolean:  // Fall-through.
568     case Primitive::kPrimByte:     // Fall-through.
569     case Primitive::kPrimChar:     // Fall-through.
570     case Primitive::kPrimShort:    // Fall-through.
571     case Primitive::kPrimInt:      // Fall-through.
572     case Primitive::kPrimFloat:
573       sf_->SetVReg(cur_reg_, *reinterpret_cast<jint*>(GetParamAddress()));
574       break;
575     case Primitive::kPrimVoid:
576       LOG(FATAL) << "UNREACHABLE";
577       UNREACHABLE();
578   }
579   ++cur_reg_;
580 }
581 
582 // Don't inline. See b/65159206.
583 NO_INLINE
HandleDeoptimization(JValue * result,ArtMethod * method,ShadowFrame * deopt_frame,ManagedStack * fragment)584 static void HandleDeoptimization(JValue* result,
585                                  ArtMethod* method,
586                                  ShadowFrame* deopt_frame,
587                                  ManagedStack* fragment)
588     REQUIRES_SHARED(Locks::mutator_lock_) {
589   // Coming from partial-fragment deopt.
590   Thread* self = Thread::Current();
591   if (kIsDebugBuild) {
592     // Sanity-check: are the methods as expected? We check that the last shadow frame (the bottom
593     // of the call-stack) corresponds to the called method.
594     ShadowFrame* linked = deopt_frame;
595     while (linked->GetLink() != nullptr) {
596       linked = linked->GetLink();
597     }
598     CHECK_EQ(method, linked->GetMethod()) << method->PrettyMethod() << " "
599         << ArtMethod::PrettyMethod(linked->GetMethod());
600   }
601 
602   if (VLOG_IS_ON(deopt)) {
603     // Print out the stack to verify that it was a partial-fragment deopt.
604     LOG(INFO) << "Continue-ing from deopt. Stack is:";
605     QuickExceptionHandler::DumpFramesWithType(self, true);
606   }
607 
608   ObjPtr<mirror::Throwable> pending_exception;
609   bool from_code = false;
610   DeoptimizationMethodType method_type;
611   self->PopDeoptimizationContext(/* out */ result,
612                                  /* out */ &pending_exception,
613                                  /* out */ &from_code,
614                                  /* out */ &method_type);
615 
616   // Push a transition back into managed code onto the linked list in thread.
617   self->PushManagedStackFragment(fragment);
618 
619   // Ensure that the stack is still in order.
620   if (kIsDebugBuild) {
621     class DummyStackVisitor : public StackVisitor {
622      public:
623       explicit DummyStackVisitor(Thread* self_in) REQUIRES_SHARED(Locks::mutator_lock_)
624           : StackVisitor(self_in, nullptr, StackVisitor::StackWalkKind::kIncludeInlinedFrames) {}
625 
626       bool VisitFrame() override REQUIRES_SHARED(Locks::mutator_lock_) {
627         // Nothing to do here. In a debug build, SanityCheckFrame will do the work in the walking
628         // logic. Just always say we want to continue.
629         return true;
630       }
631     };
632     DummyStackVisitor dsv(self);
633     dsv.WalkStack();
634   }
635 
636   // Restore the exception that was pending before deoptimization then interpret the
637   // deoptimized frames.
638   if (pending_exception != nullptr) {
639     self->SetException(pending_exception);
640   }
641   interpreter::EnterInterpreterFromDeoptimize(self,
642                                               deopt_frame,
643                                               result,
644                                               from_code,
645                                               DeoptimizationMethodType::kDefault);
646 }
647 
artQuickToInterpreterBridge(ArtMethod * method,Thread * self,ArtMethod ** sp)648 extern "C" uint64_t artQuickToInterpreterBridge(ArtMethod* method, Thread* self, ArtMethod** sp)
649     REQUIRES_SHARED(Locks::mutator_lock_) {
650   // Ensure we don't get thread suspension until the object arguments are safely in the shadow
651   // frame.
652   ScopedQuickEntrypointChecks sqec(self);
653 
654   if (UNLIKELY(!method->IsInvokable())) {
655     method->ThrowInvocationTimeError();
656     return 0;
657   }
658 
659   JValue tmp_value;
660   ShadowFrame* deopt_frame = self->PopStackedShadowFrame(
661       StackedShadowFrameType::kDeoptimizationShadowFrame, false);
662   ManagedStack fragment;
663 
664   DCHECK(!method->IsNative()) << method->PrettyMethod();
665   uint32_t shorty_len = 0;
666   ArtMethod* non_proxy_method = method->GetInterfaceMethodIfProxy(kRuntimePointerSize);
667   DCHECK(non_proxy_method->GetCodeItem() != nullptr) << method->PrettyMethod();
668   CodeItemDataAccessor accessor(non_proxy_method->DexInstructionData());
669   const char* shorty = non_proxy_method->GetShorty(&shorty_len);
670 
671   JValue result;
672   bool force_frame_pop = false;
673 
674   if (UNLIKELY(deopt_frame != nullptr)) {
675     HandleDeoptimization(&result, method, deopt_frame, &fragment);
676   } else {
677     const char* old_cause = self->StartAssertNoThreadSuspension(
678         "Building interpreter shadow frame");
679     uint16_t num_regs = accessor.RegistersSize();
680     // No last shadow coming from quick.
681     ShadowFrameAllocaUniquePtr shadow_frame_unique_ptr =
682         CREATE_SHADOW_FRAME(num_regs, /* link= */ nullptr, method, /* dex_pc= */ 0);
683     ShadowFrame* shadow_frame = shadow_frame_unique_ptr.get();
684     size_t first_arg_reg = accessor.RegistersSize() - accessor.InsSize();
685     BuildQuickShadowFrameVisitor shadow_frame_builder(sp, method->IsStatic(), shorty, shorty_len,
686                                                       shadow_frame, first_arg_reg);
687     shadow_frame_builder.VisitArguments();
688     // Push a transition back into managed code onto the linked list in thread.
689     self->PushManagedStackFragment(&fragment);
690     self->PushShadowFrame(shadow_frame);
691     self->EndAssertNoThreadSuspension(old_cause);
692 
693     if (NeedsClinitCheckBeforeCall(method)) {
694       ObjPtr<mirror::Class> declaring_class = method->GetDeclaringClass();
695       if (UNLIKELY(!declaring_class->IsVisiblyInitialized())) {
696         // Ensure static method's class is initialized.
697         StackHandleScope<1> hs(self);
698         Handle<mirror::Class> h_class(hs.NewHandle(declaring_class));
699         if (!Runtime::Current()->GetClassLinker()->EnsureInitialized(self, h_class, true, true)) {
700           DCHECK(Thread::Current()->IsExceptionPending()) << method->PrettyMethod();
701           self->PopManagedStackFragment(fragment);
702           return 0;
703         }
704       }
705     }
706 
707     result = interpreter::EnterInterpreterFromEntryPoint(self, accessor, shadow_frame);
708     force_frame_pop = shadow_frame->GetForcePopFrame();
709   }
710 
711   // Pop transition.
712   self->PopManagedStackFragment(fragment);
713 
714   // Request a stack deoptimization if needed
715   ArtMethod* caller = QuickArgumentVisitor::GetCallingMethod(sp);
716   uintptr_t caller_pc = QuickArgumentVisitor::GetCallingPc(sp);
717   // If caller_pc is the instrumentation exit stub, the stub will check to see if deoptimization
718   // should be done and it knows the real return pc. NB If the upcall is null we don't need to do
719   // anything. This can happen during shutdown or early startup.
720   if (UNLIKELY(
721           caller != nullptr &&
722           caller_pc != reinterpret_cast<uintptr_t>(GetQuickInstrumentationExitPc()) &&
723           (self->IsForceInterpreter() || Dbg::IsForcedInterpreterNeededForUpcall(self, caller)))) {
724     if (!Runtime::Current()->IsAsyncDeoptimizeable(caller_pc)) {
725       LOG(WARNING) << "Got a deoptimization request on un-deoptimizable method "
726                    << caller->PrettyMethod();
727     } else {
728       VLOG(deopt) << "Forcing deoptimization on return from method " << method->PrettyMethod()
729                   << " to " << caller->PrettyMethod()
730                   << (force_frame_pop ? " for frame-pop" : "");
731       DCHECK(!force_frame_pop || result.GetJ() == 0) << "Force frame pop should have no result.";
732       if (force_frame_pop && self->GetException() != nullptr) {
733         LOG(WARNING) << "Suppressing exception for instruction-retry: "
734                      << self->GetException()->Dump();
735       }
736       // Push the context of the deoptimization stack so we can restore the return value and the
737       // exception before executing the deoptimized frames.
738       self->PushDeoptimizationContext(
739           result,
740           shorty[0] == 'L' || shorty[0] == '[',  /* class or array */
741           force_frame_pop ? nullptr : self->GetException(),
742           /* from_code= */ false,
743           DeoptimizationMethodType::kDefault);
744 
745       // Set special exception to cause deoptimization.
746       self->SetException(Thread::GetDeoptimizationException());
747     }
748   }
749 
750   // No need to restore the args since the method has already been run by the interpreter.
751   return result.GetJ();
752 }
753 
754 // Visits arguments on the stack placing them into the args vector, Object* arguments are converted
755 // to jobjects.
756 class BuildQuickArgumentVisitor final : public QuickArgumentVisitor {
757  public:
BuildQuickArgumentVisitor(ArtMethod ** sp,bool is_static,const char * shorty,uint32_t shorty_len,ScopedObjectAccessUnchecked * soa,std::vector<jvalue> * args)758   BuildQuickArgumentVisitor(ArtMethod** sp, bool is_static, const char* shorty, uint32_t shorty_len,
759                             ScopedObjectAccessUnchecked* soa, std::vector<jvalue>* args) :
760       QuickArgumentVisitor(sp, is_static, shorty, shorty_len), soa_(soa), args_(args) {}
761 
762   void Visit() REQUIRES_SHARED(Locks::mutator_lock_) override;
763 
764  private:
765   ScopedObjectAccessUnchecked* const soa_;
766   std::vector<jvalue>* const args_;
767 
768   DISALLOW_COPY_AND_ASSIGN(BuildQuickArgumentVisitor);
769 };
770 
Visit()771 void BuildQuickArgumentVisitor::Visit() {
772   jvalue val;
773   Primitive::Type type = GetParamPrimitiveType();
774   switch (type) {
775     case Primitive::kPrimNot: {
776       StackReference<mirror::Object>* stack_ref =
777           reinterpret_cast<StackReference<mirror::Object>*>(GetParamAddress());
778       val.l = soa_->AddLocalReference<jobject>(stack_ref->AsMirrorPtr());
779       break;
780     }
781     case Primitive::kPrimLong:  // Fall-through.
782     case Primitive::kPrimDouble:
783       if (IsSplitLongOrDouble()) {
784         val.j = ReadSplitLongParam();
785       } else {
786         val.j = *reinterpret_cast<jlong*>(GetParamAddress());
787       }
788       break;
789     case Primitive::kPrimBoolean:  // Fall-through.
790     case Primitive::kPrimByte:     // Fall-through.
791     case Primitive::kPrimChar:     // Fall-through.
792     case Primitive::kPrimShort:    // Fall-through.
793     case Primitive::kPrimInt:      // Fall-through.
794     case Primitive::kPrimFloat:
795       val.i = *reinterpret_cast<jint*>(GetParamAddress());
796       break;
797     case Primitive::kPrimVoid:
798       LOG(FATAL) << "UNREACHABLE";
799       UNREACHABLE();
800   }
801   args_->push_back(val);
802 }
803 
804 // Handler for invocation on proxy methods. On entry a frame will exist for the proxy object method
805 // which is responsible for recording callee save registers. We explicitly place into jobjects the
806 // incoming reference arguments (so they survive GC). We invoke the invocation handler, which is a
807 // field within the proxy object, which will box the primitive arguments and deal with error cases.
artQuickProxyInvokeHandler(ArtMethod * proxy_method,mirror::Object * receiver,Thread * self,ArtMethod ** sp)808 extern "C" uint64_t artQuickProxyInvokeHandler(
809     ArtMethod* proxy_method, mirror::Object* receiver, Thread* self, ArtMethod** sp)
810     REQUIRES_SHARED(Locks::mutator_lock_) {
811   DCHECK(proxy_method->IsProxyMethod()) << proxy_method->PrettyMethod();
812   DCHECK(receiver->GetClass()->IsProxyClass()) << proxy_method->PrettyMethod();
813   // Ensure we don't get thread suspension until the object arguments are safely in jobjects.
814   const char* old_cause =
815       self->StartAssertNoThreadSuspension("Adding to IRT proxy object arguments");
816   // Register the top of the managed stack, making stack crawlable.
817   DCHECK_EQ((*sp), proxy_method) << proxy_method->PrettyMethod();
818   self->VerifyStack();
819   // Start new JNI local reference state.
820   JNIEnvExt* env = self->GetJniEnv();
821   ScopedObjectAccessUnchecked soa(env);
822   ScopedJniEnvLocalRefState env_state(env);
823   // Create local ref. copies of proxy method and the receiver.
824   jobject rcvr_jobj = soa.AddLocalReference<jobject>(receiver);
825 
826   // Placing arguments into args vector and remove the receiver.
827   ArtMethod* non_proxy_method = proxy_method->GetInterfaceMethodIfProxy(kRuntimePointerSize);
828   CHECK(!non_proxy_method->IsStatic()) << proxy_method->PrettyMethod() << " "
829                                        << non_proxy_method->PrettyMethod();
830   std::vector<jvalue> args;
831   uint32_t shorty_len = 0;
832   const char* shorty = non_proxy_method->GetShorty(&shorty_len);
833   BuildQuickArgumentVisitor local_ref_visitor(
834       sp, /* is_static= */ false, shorty, shorty_len, &soa, &args);
835 
836   local_ref_visitor.VisitArguments();
837   DCHECK_GT(args.size(), 0U) << proxy_method->PrettyMethod();
838   args.erase(args.begin());
839 
840   // Convert proxy method into expected interface method.
841   ArtMethod* interface_method = proxy_method->FindOverriddenMethod(kRuntimePointerSize);
842   DCHECK(interface_method != nullptr) << proxy_method->PrettyMethod();
843   DCHECK(!interface_method->IsProxyMethod()) << interface_method->PrettyMethod();
844   self->EndAssertNoThreadSuspension(old_cause);
845   DCHECK_EQ(Runtime::Current()->GetClassLinker()->GetImagePointerSize(), kRuntimePointerSize);
846   DCHECK(!Runtime::Current()->IsActiveTransaction());
847   ObjPtr<mirror::Method> interface_reflect_method =
848       mirror::Method::CreateFromArtMethod<kRuntimePointerSize, false>(soa.Self(), interface_method);
849   if (interface_reflect_method == nullptr) {
850     soa.Self()->AssertPendingOOMException();
851     return 0;
852   }
853   jobject interface_method_jobj = soa.AddLocalReference<jobject>(interface_reflect_method);
854 
855   // All naked Object*s should now be in jobjects, so its safe to go into the main invoke code
856   // that performs allocations or instrumentation events.
857   instrumentation::Instrumentation* instr = Runtime::Current()->GetInstrumentation();
858   if (instr->HasMethodEntryListeners()) {
859     instr->MethodEnterEvent(soa.Self(),
860                             soa.Decode<mirror::Object>(rcvr_jobj),
861                             proxy_method,
862                             0);
863     if (soa.Self()->IsExceptionPending()) {
864       instr->MethodUnwindEvent(self,
865                                soa.Decode<mirror::Object>(rcvr_jobj),
866                                proxy_method,
867                                0);
868       return 0;
869     }
870   }
871   JValue result = InvokeProxyInvocationHandler(soa, shorty, rcvr_jobj, interface_method_jobj, args);
872   if (soa.Self()->IsExceptionPending()) {
873     if (instr->HasMethodUnwindListeners()) {
874       instr->MethodUnwindEvent(self,
875                                soa.Decode<mirror::Object>(rcvr_jobj),
876                                proxy_method,
877                                0);
878     }
879   } else if (instr->HasMethodExitListeners()) {
880     instr->MethodExitEvent(self,
881                            soa.Decode<mirror::Object>(rcvr_jobj),
882                            proxy_method,
883                            0,
884                            {},
885                            result);
886   }
887   return result.GetJ();
888 }
889 
890 // Visitor returning a reference argument at a given position in a Quick stack frame.
891 // NOTE: Only used for testing purposes.
892 class GetQuickReferenceArgumentAtVisitor final : public QuickArgumentVisitor {
893  public:
GetQuickReferenceArgumentAtVisitor(ArtMethod ** sp,const char * shorty,uint32_t shorty_len,size_t arg_pos)894   GetQuickReferenceArgumentAtVisitor(ArtMethod** sp,
895                                      const char* shorty,
896                                      uint32_t shorty_len,
897                                      size_t arg_pos)
898       : QuickArgumentVisitor(sp, /* is_static= */ false, shorty, shorty_len),
899         cur_pos_(0u),
900         arg_pos_(arg_pos),
901         ref_arg_(nullptr) {
902           CHECK_LT(arg_pos, shorty_len) << "Argument position greater than the number arguments";
903         }
904 
Visit()905   void Visit() REQUIRES_SHARED(Locks::mutator_lock_) override {
906     if (cur_pos_ == arg_pos_) {
907       Primitive::Type type = GetParamPrimitiveType();
908       CHECK_EQ(type, Primitive::kPrimNot) << "Argument at searched position is not a reference";
909       ref_arg_ = reinterpret_cast<StackReference<mirror::Object>*>(GetParamAddress());
910     }
911     ++cur_pos_;
912   }
913 
GetReferenceArgument()914   StackReference<mirror::Object>* GetReferenceArgument() {
915     return ref_arg_;
916   }
917 
918  private:
919   // The position of the currently visited argument.
920   size_t cur_pos_;
921   // The position of the searched argument.
922   const size_t arg_pos_;
923   // The reference argument, if found.
924   StackReference<mirror::Object>* ref_arg_;
925 
926   DISALLOW_COPY_AND_ASSIGN(GetQuickReferenceArgumentAtVisitor);
927 };
928 
929 // Returning reference argument at position `arg_pos` in Quick stack frame at address `sp`.
930 // NOTE: Only used for testing purposes.
artQuickGetProxyReferenceArgumentAt(size_t arg_pos,ArtMethod ** sp)931 extern "C" StackReference<mirror::Object>* artQuickGetProxyReferenceArgumentAt(size_t arg_pos,
932                                                                                ArtMethod** sp)
933     REQUIRES_SHARED(Locks::mutator_lock_) {
934   ArtMethod* proxy_method = *sp;
935   ArtMethod* non_proxy_method = proxy_method->GetInterfaceMethodIfProxy(kRuntimePointerSize);
936   CHECK(!non_proxy_method->IsStatic())
937       << proxy_method->PrettyMethod() << " " << non_proxy_method->PrettyMethod();
938   uint32_t shorty_len = 0;
939   const char* shorty = non_proxy_method->GetShorty(&shorty_len);
940   GetQuickReferenceArgumentAtVisitor ref_arg_visitor(sp, shorty, shorty_len, arg_pos);
941   ref_arg_visitor.VisitArguments();
942   StackReference<mirror::Object>* ref_arg = ref_arg_visitor.GetReferenceArgument();
943   return ref_arg;
944 }
945 
946 // Visitor returning all the reference arguments in a Quick stack frame.
947 class GetQuickReferenceArgumentsVisitor final : public QuickArgumentVisitor {
948  public:
GetQuickReferenceArgumentsVisitor(ArtMethod ** sp,bool is_static,const char * shorty,uint32_t shorty_len)949   GetQuickReferenceArgumentsVisitor(ArtMethod** sp,
950                                     bool is_static,
951                                     const char* shorty,
952                                     uint32_t shorty_len)
953       : QuickArgumentVisitor(sp, is_static, shorty, shorty_len) {}
954 
Visit()955   void Visit() REQUIRES_SHARED(Locks::mutator_lock_) override {
956     Primitive::Type type = GetParamPrimitiveType();
957     if (type == Primitive::kPrimNot) {
958       StackReference<mirror::Object>* ref_arg =
959           reinterpret_cast<StackReference<mirror::Object>*>(GetParamAddress());
960       ref_args_.push_back(ref_arg);
961     }
962   }
963 
GetReferenceArguments()964   std::vector<StackReference<mirror::Object>*> GetReferenceArguments() {
965     return ref_args_;
966   }
967 
968  private:
969   // The reference arguments.
970   std::vector<StackReference<mirror::Object>*> ref_args_;
971 
972   DISALLOW_COPY_AND_ASSIGN(GetQuickReferenceArgumentsVisitor);
973 };
974 
975 // Returning all reference arguments in Quick stack frame at address `sp`.
GetProxyReferenceArguments(ArtMethod ** sp)976 std::vector<StackReference<mirror::Object>*> GetProxyReferenceArguments(ArtMethod** sp)
977     REQUIRES_SHARED(Locks::mutator_lock_) {
978   ArtMethod* proxy_method = *sp;
979   ArtMethod* non_proxy_method = proxy_method->GetInterfaceMethodIfProxy(kRuntimePointerSize);
980   CHECK(!non_proxy_method->IsStatic())
981       << proxy_method->PrettyMethod() << " " << non_proxy_method->PrettyMethod();
982   uint32_t shorty_len = 0;
983   const char* shorty = non_proxy_method->GetShorty(&shorty_len);
984   GetQuickReferenceArgumentsVisitor ref_args_visitor(sp, /*is_static=*/ false, shorty, shorty_len);
985   ref_args_visitor.VisitArguments();
986   std::vector<StackReference<mirror::Object>*> ref_args = ref_args_visitor.GetReferenceArguments();
987   return ref_args;
988 }
989 
990 // Read object references held in arguments from quick frames and place in a JNI local references,
991 // so they don't get garbage collected.
992 class RememberForGcArgumentVisitor final : public QuickArgumentVisitor {
993  public:
RememberForGcArgumentVisitor(ArtMethod ** sp,bool is_static,const char * shorty,uint32_t shorty_len,ScopedObjectAccessUnchecked * soa)994   RememberForGcArgumentVisitor(ArtMethod** sp, bool is_static, const char* shorty,
995                                uint32_t shorty_len, ScopedObjectAccessUnchecked* soa) :
996       QuickArgumentVisitor(sp, is_static, shorty, shorty_len), soa_(soa) {}
997 
998   void Visit() REQUIRES_SHARED(Locks::mutator_lock_) override;
999 
1000   void FixupReferences() REQUIRES_SHARED(Locks::mutator_lock_);
1001 
1002  private:
1003   ScopedObjectAccessUnchecked* const soa_;
1004   // References which we must update when exiting in case the GC moved the objects.
1005   std::vector<std::pair<jobject, StackReference<mirror::Object>*> > references_;
1006 
1007   DISALLOW_COPY_AND_ASSIGN(RememberForGcArgumentVisitor);
1008 };
1009 
Visit()1010 void RememberForGcArgumentVisitor::Visit() {
1011   if (IsParamAReference()) {
1012     StackReference<mirror::Object>* stack_ref =
1013         reinterpret_cast<StackReference<mirror::Object>*>(GetParamAddress());
1014     jobject reference =
1015         soa_->AddLocalReference<jobject>(stack_ref->AsMirrorPtr());
1016     references_.push_back(std::make_pair(reference, stack_ref));
1017   }
1018 }
1019 
FixupReferences()1020 void RememberForGcArgumentVisitor::FixupReferences() {
1021   // Fixup any references which may have changed.
1022   for (const auto& pair : references_) {
1023     pair.second->Assign(soa_->Decode<mirror::Object>(pair.first));
1024     soa_->Env()->DeleteLocalRef(pair.first);
1025   }
1026 }
1027 
artInstrumentationMethodEntryFromCode(ArtMethod * method,mirror::Object * this_object,Thread * self,ArtMethod ** sp)1028 extern "C" const void* artInstrumentationMethodEntryFromCode(ArtMethod* method,
1029                                                              mirror::Object* this_object,
1030                                                              Thread* self,
1031                                                              ArtMethod** sp)
1032     REQUIRES_SHARED(Locks::mutator_lock_) {
1033   const void* result;
1034   // Instrumentation changes the stack. Thus, when exiting, the stack cannot be verified, so skip
1035   // that part.
1036   ScopedQuickEntrypointChecks sqec(self, kIsDebugBuild, false);
1037   instrumentation::Instrumentation* instrumentation = Runtime::Current()->GetInstrumentation();
1038   DCHECK(!method->IsProxyMethod())
1039       << "Proxy method " << method->PrettyMethod()
1040       << " (declaring class: " << method->GetDeclaringClass()->PrettyClass() << ")"
1041       << " should not hit instrumentation entrypoint.";
1042   if (instrumentation->IsDeoptimized(method)) {
1043     result = GetQuickToInterpreterBridge();
1044   } else {
1045     // This will get the entry point either from the oat file, the JIT or the appropriate bridge
1046     // method if none of those can be found.
1047     result = instrumentation->GetCodeForInvoke(method);
1048     jit::Jit* jit = Runtime::Current()->GetJit();
1049     DCHECK_NE(result, GetQuickInstrumentationEntryPoint()) << method->PrettyMethod();
1050     DCHECK(jit == nullptr ||
1051            // Native methods come through here in Interpreter entrypoints. We might not have
1052            // disabled jit-gc but that is fine since we won't return jit-code for native methods.
1053            method->IsNative() ||
1054            !jit->GetCodeCache()->GetGarbageCollectCode());
1055     DCHECK(!method->IsNative() ||
1056            jit == nullptr ||
1057            !jit->GetCodeCache()->ContainsPc(result))
1058         << method->PrettyMethod() << " code will jump to possibly cleaned up jit code!";
1059   }
1060 
1061   bool interpreter_entry = (result == GetQuickToInterpreterBridge());
1062   bool is_static = method->IsStatic();
1063   uint32_t shorty_len;
1064   const char* shorty =
1065       method->GetInterfaceMethodIfProxy(kRuntimePointerSize)->GetShorty(&shorty_len);
1066 
1067   ScopedObjectAccessUnchecked soa(self);
1068   RememberForGcArgumentVisitor visitor(sp, is_static, shorty, shorty_len, &soa);
1069   visitor.VisitArguments();
1070 
1071   instrumentation->PushInstrumentationStackFrame(self,
1072                                                  is_static ? nullptr : this_object,
1073                                                  method,
1074                                                  reinterpret_cast<uintptr_t>(
1075                                                      QuickArgumentVisitor::GetCallingPcAddr(sp)),
1076                                                  QuickArgumentVisitor::GetCallingPc(sp),
1077                                                  interpreter_entry);
1078 
1079   visitor.FixupReferences();
1080   if (UNLIKELY(self->IsExceptionPending())) {
1081     return nullptr;
1082   }
1083   CHECK(result != nullptr) << method->PrettyMethod();
1084   return result;
1085 }
1086 
artInstrumentationMethodExitFromCode(Thread * self,ArtMethod ** sp,uint64_t * gpr_result,uint64_t * fpr_result)1087 extern "C" TwoWordReturn artInstrumentationMethodExitFromCode(Thread* self,
1088                                                               ArtMethod** sp,
1089                                                               uint64_t* gpr_result,
1090                                                               uint64_t* fpr_result)
1091     REQUIRES_SHARED(Locks::mutator_lock_) {
1092   DCHECK_EQ(reinterpret_cast<uintptr_t>(self), reinterpret_cast<uintptr_t>(Thread::Current()));
1093   CHECK(gpr_result != nullptr);
1094   CHECK(fpr_result != nullptr);
1095   // Instrumentation exit stub must not be entered with a pending exception.
1096   CHECK(!self->IsExceptionPending()) << "Enter instrumentation exit stub with pending exception "
1097                                      << self->GetException()->Dump();
1098   // Compute address of return PC and sanity check that it currently holds 0.
1099   constexpr size_t return_pc_offset =
1100       RuntimeCalleeSaveFrame::GetReturnPcOffset(CalleeSaveType::kSaveEverything);
1101   uintptr_t* return_pc_addr = reinterpret_cast<uintptr_t*>(reinterpret_cast<uint8_t*>(sp) +
1102                                                            return_pc_offset);
1103   CHECK_EQ(*return_pc_addr, 0U);
1104 
1105   // Pop the frame filling in the return pc. The low half of the return value is 0 when
1106   // deoptimization shouldn't be performed with the high-half having the return address. When
1107   // deoptimization should be performed the low half is zero and the high-half the address of the
1108   // deoptimization entry point.
1109   instrumentation::Instrumentation* instrumentation = Runtime::Current()->GetInstrumentation();
1110   TwoWordReturn return_or_deoptimize_pc = instrumentation->PopInstrumentationStackFrame(
1111       self, return_pc_addr, gpr_result, fpr_result);
1112   if (self->IsExceptionPending() || self->ObserveAsyncException()) {
1113     return GetTwoWordFailureValue();
1114   }
1115   return return_or_deoptimize_pc;
1116 }
1117 
DumpInstruction(ArtMethod * method,uint32_t dex_pc)1118 static std::string DumpInstruction(ArtMethod* method, uint32_t dex_pc)
1119     REQUIRES_SHARED(Locks::mutator_lock_) {
1120   if (dex_pc == static_cast<uint32_t>(-1)) {
1121     CHECK(method == jni::DecodeArtMethod(WellKnownClasses::java_lang_String_charAt));
1122     return "<native>";
1123   } else {
1124     CodeItemInstructionAccessor accessor = method->DexInstructions();
1125     CHECK_LT(dex_pc, accessor.InsnsSizeInCodeUnits());
1126     return accessor.InstructionAt(dex_pc).DumpString(method->GetDexFile());
1127   }
1128 }
1129 
DumpB74410240ClassData(ObjPtr<mirror::Class> klass)1130 static void DumpB74410240ClassData(ObjPtr<mirror::Class> klass)
1131     REQUIRES_SHARED(Locks::mutator_lock_) {
1132   std::string storage;
1133   const char* descriptor = klass->GetDescriptor(&storage);
1134   LOG(FATAL_WITHOUT_ABORT) << "  " << DescribeLoaders(klass->GetClassLoader(), descriptor);
1135   const OatDexFile* oat_dex_file = klass->GetDexFile().GetOatDexFile();
1136   if (oat_dex_file != nullptr) {
1137     const OatFile* oat_file = oat_dex_file->GetOatFile();
1138     const char* dex2oat_cmdline =
1139         oat_file->GetOatHeader().GetStoreValueByKey(OatHeader::kDex2OatCmdLineKey);
1140     LOG(FATAL_WITHOUT_ABORT) << "    OatFile: " << oat_file->GetLocation()
1141         << "; " << (dex2oat_cmdline != nullptr ? dex2oat_cmdline : "<not recorded>");
1142   }
1143 }
1144 
DumpB74410240DebugData(ArtMethod ** sp)1145 static void DumpB74410240DebugData(ArtMethod** sp) REQUIRES_SHARED(Locks::mutator_lock_) {
1146   // Mimick the search for the caller and dump some data while doing so.
1147   LOG(FATAL_WITHOUT_ABORT) << "Dumping debugging data, please attach a bugreport to b/74410240.";
1148 
1149   constexpr CalleeSaveType type = CalleeSaveType::kSaveRefsAndArgs;
1150   CHECK_EQ(*sp, Runtime::Current()->GetCalleeSaveMethod(type));
1151 
1152   constexpr size_t callee_frame_size = RuntimeCalleeSaveFrame::GetFrameSize(type);
1153   auto** caller_sp = reinterpret_cast<ArtMethod**>(
1154       reinterpret_cast<uintptr_t>(sp) + callee_frame_size);
1155   constexpr size_t callee_return_pc_offset = RuntimeCalleeSaveFrame::GetReturnPcOffset(type);
1156   uintptr_t caller_pc = *reinterpret_cast<uintptr_t*>(
1157       (reinterpret_cast<uint8_t*>(sp) + callee_return_pc_offset));
1158   ArtMethod* outer_method = *caller_sp;
1159 
1160   if (UNLIKELY(caller_pc == reinterpret_cast<uintptr_t>(GetQuickInstrumentationExitPc()))) {
1161     LOG(FATAL_WITHOUT_ABORT) << "Method: " << outer_method->PrettyMethod()
1162         << " native pc: " << caller_pc << " Instrumented!";
1163     return;
1164   }
1165 
1166   const OatQuickMethodHeader* current_code = outer_method->GetOatQuickMethodHeader(caller_pc);
1167   CHECK(current_code != nullptr);
1168   CHECK(current_code->IsOptimized());
1169   uintptr_t native_pc_offset = current_code->NativeQuickPcOffset(caller_pc);
1170   CodeInfo code_info(current_code);
1171   StackMap stack_map = code_info.GetStackMapForNativePcOffset(native_pc_offset);
1172   CHECK(stack_map.IsValid());
1173   uint32_t dex_pc = stack_map.GetDexPc();
1174 
1175   // Log the outer method and its associated dex file and class table pointer which can be used
1176   // to find out if the inlined methods were defined by other dex file(s) or class loader(s).
1177   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
1178   LOG(FATAL_WITHOUT_ABORT) << "Outer: " << outer_method->PrettyMethod()
1179       << " native pc: " << caller_pc
1180       << " dex pc: " << dex_pc
1181       << " dex file: " << outer_method->GetDexFile()->GetLocation()
1182       << " class table: " << class_linker->ClassTableForClassLoader(outer_method->GetClassLoader());
1183   DumpB74410240ClassData(outer_method->GetDeclaringClass());
1184   LOG(FATAL_WITHOUT_ABORT) << "  instruction: " << DumpInstruction(outer_method, dex_pc);
1185 
1186   ArtMethod* caller = outer_method;
1187   BitTableRange<InlineInfo> inline_infos = code_info.GetInlineInfosOf(stack_map);
1188   for (InlineInfo inline_info : inline_infos) {
1189     const char* tag = "";
1190     dex_pc = inline_info.GetDexPc();
1191     if (inline_info.EncodesArtMethod()) {
1192       tag = "encoded ";
1193       caller = inline_info.GetArtMethod();
1194     } else {
1195       uint32_t method_index = code_info.GetMethodIndexOf(inline_info);
1196       if (dex_pc == static_cast<uint32_t>(-1)) {
1197         tag = "special ";
1198         CHECK(inline_info.Equals(inline_infos.back()));
1199         caller = jni::DecodeArtMethod(WellKnownClasses::java_lang_String_charAt);
1200         CHECK_EQ(caller->GetDexMethodIndex(), method_index);
1201       } else {
1202         ObjPtr<mirror::DexCache> dex_cache = caller->GetDexCache();
1203         ObjPtr<mirror::ClassLoader> class_loader = caller->GetClassLoader();
1204         caller = class_linker->LookupResolvedMethod(method_index, dex_cache, class_loader);
1205         CHECK(caller != nullptr);
1206       }
1207     }
1208     LOG(FATAL_WITHOUT_ABORT) << "InlineInfo #" << inline_info.Row()
1209         << ": " << tag << caller->PrettyMethod()
1210         << " dex pc: " << dex_pc
1211         << " dex file: " << caller->GetDexFile()->GetLocation()
1212         << " class table: "
1213         << class_linker->ClassTableForClassLoader(caller->GetClassLoader());
1214     DumpB74410240ClassData(caller->GetDeclaringClass());
1215     LOG(FATAL_WITHOUT_ABORT) << "  instruction: " << DumpInstruction(caller, dex_pc);
1216   }
1217 }
1218 
1219 // Lazily resolve a method for quick. Called by stub code.
artQuickResolutionTrampoline(ArtMethod * called,mirror::Object * receiver,Thread * self,ArtMethod ** sp)1220 extern "C" const void* artQuickResolutionTrampoline(
1221     ArtMethod* called, mirror::Object* receiver, Thread* self, ArtMethod** sp)
1222     REQUIRES_SHARED(Locks::mutator_lock_) {
1223   // The resolution trampoline stashes the resolved method into the callee-save frame to transport
1224   // it. Thus, when exiting, the stack cannot be verified (as the resolved method most likely
1225   // does not have the same stack layout as the callee-save method).
1226   ScopedQuickEntrypointChecks sqec(self, kIsDebugBuild, false);
1227   // Start new JNI local reference state
1228   JNIEnvExt* env = self->GetJniEnv();
1229   ScopedObjectAccessUnchecked soa(env);
1230   ScopedJniEnvLocalRefState env_state(env);
1231   const char* old_cause = self->StartAssertNoThreadSuspension("Quick method resolution set up");
1232 
1233   // Compute details about the called method (avoid GCs)
1234   ClassLinker* linker = Runtime::Current()->GetClassLinker();
1235   InvokeType invoke_type;
1236   MethodReference called_method(nullptr, 0);
1237   const bool called_method_known_on_entry = !called->IsRuntimeMethod();
1238   ArtMethod* caller = nullptr;
1239   if (!called_method_known_on_entry) {
1240     caller = QuickArgumentVisitor::GetCallingMethod(sp);
1241     called_method.dex_file = caller->GetDexFile();
1242 
1243     {
1244       uint32_t dex_pc = QuickArgumentVisitor::GetCallingDexPc(sp);
1245       CodeItemInstructionAccessor accessor(caller->DexInstructions());
1246       CHECK_LT(dex_pc, accessor.InsnsSizeInCodeUnits());
1247       const Instruction& instr = accessor.InstructionAt(dex_pc);
1248       Instruction::Code instr_code = instr.Opcode();
1249       bool is_range;
1250       switch (instr_code) {
1251         case Instruction::INVOKE_DIRECT:
1252           invoke_type = kDirect;
1253           is_range = false;
1254           break;
1255         case Instruction::INVOKE_DIRECT_RANGE:
1256           invoke_type = kDirect;
1257           is_range = true;
1258           break;
1259         case Instruction::INVOKE_STATIC:
1260           invoke_type = kStatic;
1261           is_range = false;
1262           break;
1263         case Instruction::INVOKE_STATIC_RANGE:
1264           invoke_type = kStatic;
1265           is_range = true;
1266           break;
1267         case Instruction::INVOKE_SUPER:
1268           invoke_type = kSuper;
1269           is_range = false;
1270           break;
1271         case Instruction::INVOKE_SUPER_RANGE:
1272           invoke_type = kSuper;
1273           is_range = true;
1274           break;
1275         case Instruction::INVOKE_VIRTUAL:
1276           invoke_type = kVirtual;
1277           is_range = false;
1278           break;
1279         case Instruction::INVOKE_VIRTUAL_RANGE:
1280           invoke_type = kVirtual;
1281           is_range = true;
1282           break;
1283         case Instruction::INVOKE_INTERFACE:
1284           invoke_type = kInterface;
1285           is_range = false;
1286           break;
1287         case Instruction::INVOKE_INTERFACE_RANGE:
1288           invoke_type = kInterface;
1289           is_range = true;
1290           break;
1291         default:
1292           DumpB74410240DebugData(sp);
1293           LOG(FATAL) << "Unexpected call into trampoline: " << instr.DumpString(nullptr);
1294           UNREACHABLE();
1295       }
1296       called_method.index = (is_range) ? instr.VRegB_3rc() : instr.VRegB_35c();
1297       VLOG(dex) << "Accessed dex file for invoke " << invoke_type << " "
1298                 << called_method.index;
1299     }
1300   } else {
1301     invoke_type = kStatic;
1302     called_method.dex_file = called->GetDexFile();
1303     called_method.index = called->GetDexMethodIndex();
1304   }
1305   uint32_t shorty_len;
1306   const char* shorty =
1307       called_method.dex_file->GetMethodShorty(called_method.GetMethodId(), &shorty_len);
1308   RememberForGcArgumentVisitor visitor(sp, invoke_type == kStatic, shorty, shorty_len, &soa);
1309   visitor.VisitArguments();
1310   self->EndAssertNoThreadSuspension(old_cause);
1311   const bool virtual_or_interface = invoke_type == kVirtual || invoke_type == kInterface;
1312   // Resolve method filling in dex cache.
1313   if (!called_method_known_on_entry) {
1314     StackHandleScope<1> hs(self);
1315     mirror::Object* dummy = nullptr;
1316     HandleWrapper<mirror::Object> h_receiver(
1317         hs.NewHandleWrapper(virtual_or_interface ? &receiver : &dummy));
1318     DCHECK_EQ(caller->GetDexFile(), called_method.dex_file);
1319     called = linker->ResolveMethod<ClassLinker::ResolveMode::kCheckICCEAndIAE>(
1320         self, called_method.index, caller, invoke_type);
1321 
1322     // Update .bss entry in oat file if any.
1323     if (called != nullptr && called_method.dex_file->GetOatDexFile() != nullptr) {
1324       size_t bss_offset = IndexBssMappingLookup::GetBssOffset(
1325           called_method.dex_file->GetOatDexFile()->GetMethodBssMapping(),
1326           called_method.index,
1327           called_method.dex_file->NumMethodIds(),
1328           static_cast<size_t>(kRuntimePointerSize));
1329       if (bss_offset != IndexBssMappingLookup::npos) {
1330         DCHECK_ALIGNED(bss_offset, static_cast<size_t>(kRuntimePointerSize));
1331         const OatFile* oat_file = called_method.dex_file->GetOatDexFile()->GetOatFile();
1332         ArtMethod** method_entry = reinterpret_cast<ArtMethod**>(const_cast<uint8_t*>(
1333             oat_file->BssBegin() + bss_offset));
1334         DCHECK_GE(method_entry, oat_file->GetBssMethods().data());
1335         DCHECK_LT(method_entry,
1336                   oat_file->GetBssMethods().data() + oat_file->GetBssMethods().size());
1337         std::atomic<ArtMethod*>* atomic_entry =
1338             reinterpret_cast<std::atomic<ArtMethod*>*>(method_entry);
1339         static_assert(sizeof(*method_entry) == sizeof(*atomic_entry), "Size check.");
1340         atomic_entry->store(called, std::memory_order_release);
1341       }
1342     }
1343   }
1344   const void* code = nullptr;
1345   if (LIKELY(!self->IsExceptionPending())) {
1346     // Incompatible class change should have been handled in resolve method.
1347     CHECK(!called->CheckIncompatibleClassChange(invoke_type))
1348         << called->PrettyMethod() << " " << invoke_type;
1349     if (virtual_or_interface || invoke_type == kSuper) {
1350       // Refine called method based on receiver for kVirtual/kInterface, and
1351       // caller for kSuper.
1352       ArtMethod* orig_called = called;
1353       if (invoke_type == kVirtual) {
1354         CHECK(receiver != nullptr) << invoke_type;
1355         called = receiver->GetClass()->FindVirtualMethodForVirtual(called, kRuntimePointerSize);
1356       } else if (invoke_type == kInterface) {
1357         CHECK(receiver != nullptr) << invoke_type;
1358         called = receiver->GetClass()->FindVirtualMethodForInterface(called, kRuntimePointerSize);
1359       } else {
1360         DCHECK_EQ(invoke_type, kSuper);
1361         CHECK(caller != nullptr) << invoke_type;
1362         ObjPtr<mirror::Class> ref_class = linker->LookupResolvedType(
1363             caller->GetDexFile()->GetMethodId(called_method.index).class_idx_, caller);
1364         if (ref_class->IsInterface()) {
1365           called = ref_class->FindVirtualMethodForInterfaceSuper(called, kRuntimePointerSize);
1366         } else {
1367           called = caller->GetDeclaringClass()->GetSuperClass()->GetVTableEntry(
1368               called->GetMethodIndex(), kRuntimePointerSize);
1369         }
1370       }
1371 
1372       CHECK(called != nullptr) << orig_called->PrettyMethod() << " "
1373                                << mirror::Object::PrettyTypeOf(receiver) << " "
1374                                << invoke_type << " " << orig_called->GetVtableIndex();
1375     }
1376 
1377     ObjPtr<mirror::Class> called_class = called->GetDeclaringClass();
1378     if (NeedsClinitCheckBeforeCall(called) && !called_class->IsVisiblyInitialized()) {
1379       // Ensure that the called method's class is initialized.
1380       StackHandleScope<1> hs(soa.Self());
1381       HandleWrapperObjPtr<mirror::Class> h_called_class(hs.NewHandleWrapper(&called_class));
1382       linker->EnsureInitialized(soa.Self(), h_called_class, true, true);
1383     }
1384     bool force_interpreter = self->IsForceInterpreter() && !called->IsNative();
1385     if (called_class->IsInitialized() || called_class->IsInitializing()) {
1386       if (UNLIKELY(force_interpreter)) {
1387         // If we are single-stepping or the called method is deoptimized (by a
1388         // breakpoint, for example), then we have to execute the called method
1389         // with the interpreter.
1390         code = GetQuickToInterpreterBridge();
1391       } else {
1392         code = called->GetEntryPointFromQuickCompiledCode();
1393         if (linker->IsQuickResolutionStub(code)) {
1394           DCHECK_EQ(invoke_type, kStatic);
1395           // Go to JIT or oat and grab code.
1396           code = linker->GetQuickOatCodeFor(called);
1397           if (called_class->IsInitialized()) {
1398             // Only update the entrypoint once the class is initialized. Other
1399             // threads still need to go through the resolution stub.
1400             Runtime::Current()->GetInstrumentation()->UpdateMethodsCode(called, code);
1401           }
1402         }
1403       }
1404     } else {
1405       DCHECK(called_class->IsErroneous());
1406     }
1407   }
1408   CHECK_EQ(code == nullptr, self->IsExceptionPending());
1409   // Fixup any locally saved objects may have moved during a GC.
1410   visitor.FixupReferences();
1411   // Place called method in callee-save frame to be placed as first argument to quick method.
1412   *sp = called;
1413 
1414   return code;
1415 }
1416 
1417 /*
1418  * This class uses a couple of observations to unite the different calling conventions through
1419  * a few constants.
1420  *
1421  * 1) Number of registers used for passing is normally even, so counting down has no penalty for
1422  *    possible alignment.
1423  * 2) Known 64b architectures store 8B units on the stack, both for integral and floating point
1424  *    types, so using uintptr_t is OK. Also means that we can use kRegistersNeededX to denote
1425  *    when we have to split things
1426  * 3) The only soft-float, Arm, is 32b, so no widening needs to be taken into account for floats
1427  *    and we can use Int handling directly.
1428  * 4) Only 64b architectures widen, and their stack is aligned 8B anyways, so no padding code
1429  *    necessary when widening. Also, widening of Ints will take place implicitly, and the
1430  *    extension should be compatible with Aarch64, which mandates copying the available bits
1431  *    into LSB and leaving the rest unspecified.
1432  * 5) Aligning longs and doubles is necessary on arm only, and it's the same in registers and on
1433  *    the stack.
1434  * 6) There is only little endian.
1435  *
1436  *
1437  * Actual work is supposed to be done in a delegate of the template type. The interface is as
1438  * follows:
1439  *
1440  * void PushGpr(uintptr_t):   Add a value for the next GPR
1441  *
1442  * void PushFpr4(float):      Add a value for the next FPR of size 32b. Is only called if we need
1443  *                            padding, that is, think the architecture is 32b and aligns 64b.
1444  *
1445  * void PushFpr8(uint64_t):   Push a double. We _will_ call this on 32b, it's the callee's job to
1446  *                            split this if necessary. The current state will have aligned, if
1447  *                            necessary.
1448  *
1449  * void PushStack(uintptr_t): Push a value to the stack.
1450  *
1451  * uintptr_t PushHandleScope(mirror::Object* ref): Add a reference to the HandleScope. This _will_ have nullptr,
1452  *                                          as this might be important for null initialization.
1453  *                                          Must return the jobject, that is, the reference to the
1454  *                                          entry in the HandleScope (nullptr if necessary).
1455  *
1456  */
1457 template<class T> class BuildNativeCallFrameStateMachine {
1458  public:
1459 #if defined(__arm__)
1460   // TODO: These are all dummy values!
1461   static constexpr bool kNativeSoftFloatAbi = true;
1462   static constexpr size_t kNumNativeGprArgs = 4;  // 4 arguments passed in GPRs, r0-r3
1463   static constexpr size_t kNumNativeFprArgs = 0;  // 0 arguments passed in FPRs.
1464 
1465   static constexpr size_t kRegistersNeededForLong = 2;
1466   static constexpr size_t kRegistersNeededForDouble = 2;
1467   static constexpr bool kMultiRegistersAligned = true;
1468   static constexpr bool kMultiFPRegistersWidened = false;
1469   static constexpr bool kMultiGPRegistersWidened = false;
1470   static constexpr bool kAlignLongOnStack = true;
1471   static constexpr bool kAlignDoubleOnStack = true;
1472 #elif defined(__aarch64__)
1473   static constexpr bool kNativeSoftFloatAbi = false;  // This is a hard float ABI.
1474   static constexpr size_t kNumNativeGprArgs = 8;  // 8 arguments passed in GPRs.
1475   static constexpr size_t kNumNativeFprArgs = 8;  // 8 arguments passed in FPRs.
1476 
1477   static constexpr size_t kRegistersNeededForLong = 1;
1478   static constexpr size_t kRegistersNeededForDouble = 1;
1479   static constexpr bool kMultiRegistersAligned = false;
1480   static constexpr bool kMultiFPRegistersWidened = false;
1481   static constexpr bool kMultiGPRegistersWidened = false;
1482   static constexpr bool kAlignLongOnStack = false;
1483   static constexpr bool kAlignDoubleOnStack = false;
1484 #elif defined(__i386__)
1485   // TODO: Check these!
1486   static constexpr bool kNativeSoftFloatAbi = false;  // Not using int registers for fp
1487   static constexpr size_t kNumNativeGprArgs = 0;  // 0 arguments passed in GPRs.
1488   static constexpr size_t kNumNativeFprArgs = 0;  // 0 arguments passed in FPRs.
1489 
1490   static constexpr size_t kRegistersNeededForLong = 2;
1491   static constexpr size_t kRegistersNeededForDouble = 2;
1492   static constexpr bool kMultiRegistersAligned = false;  // x86 not using regs, anyways
1493   static constexpr bool kMultiFPRegistersWidened = false;
1494   static constexpr bool kMultiGPRegistersWidened = false;
1495   static constexpr bool kAlignLongOnStack = false;
1496   static constexpr bool kAlignDoubleOnStack = false;
1497 #elif defined(__x86_64__)
1498   static constexpr bool kNativeSoftFloatAbi = false;  // This is a hard float ABI.
1499   static constexpr size_t kNumNativeGprArgs = 6;  // 6 arguments passed in GPRs.
1500   static constexpr size_t kNumNativeFprArgs = 8;  // 8 arguments passed in FPRs.
1501 
1502   static constexpr size_t kRegistersNeededForLong = 1;
1503   static constexpr size_t kRegistersNeededForDouble = 1;
1504   static constexpr bool kMultiRegistersAligned = false;
1505   static constexpr bool kMultiFPRegistersWidened = false;
1506   static constexpr bool kMultiGPRegistersWidened = false;
1507   static constexpr bool kAlignLongOnStack = false;
1508   static constexpr bool kAlignDoubleOnStack = false;
1509 #else
1510 #error "Unsupported architecture"
1511 #endif
1512 
1513  public:
BuildNativeCallFrameStateMachine(T * delegate)1514   explicit BuildNativeCallFrameStateMachine(T* delegate)
1515       : gpr_index_(kNumNativeGprArgs),
1516         fpr_index_(kNumNativeFprArgs),
1517         stack_entries_(0),
1518         delegate_(delegate) {
1519     // For register alignment, we want to assume that counters (gpr_index_, fpr_index_) are even iff
1520     // the next register is even; counting down is just to make the compiler happy...
1521     static_assert(kNumNativeGprArgs % 2 == 0U, "Number of native GPR arguments not even");
1522     static_assert(kNumNativeFprArgs % 2 == 0U, "Number of native FPR arguments not even");
1523   }
1524 
~BuildNativeCallFrameStateMachine()1525   virtual ~BuildNativeCallFrameStateMachine() {}
1526 
HavePointerGpr() const1527   bool HavePointerGpr() const {
1528     return gpr_index_ > 0;
1529   }
1530 
AdvancePointer(const void * val)1531   void AdvancePointer(const void* val) {
1532     if (HavePointerGpr()) {
1533       gpr_index_--;
1534       PushGpr(reinterpret_cast<uintptr_t>(val));
1535     } else {
1536       stack_entries_++;  // TODO: have a field for pointer length as multiple of 32b
1537       PushStack(reinterpret_cast<uintptr_t>(val));
1538       gpr_index_ = 0;
1539     }
1540   }
1541 
HaveHandleScopeGpr() const1542   bool HaveHandleScopeGpr() const {
1543     return gpr_index_ > 0;
1544   }
1545 
AdvanceHandleScope(mirror::Object * ptr)1546   void AdvanceHandleScope(mirror::Object* ptr) REQUIRES_SHARED(Locks::mutator_lock_) {
1547     uintptr_t handle = PushHandle(ptr);
1548     if (HaveHandleScopeGpr()) {
1549       gpr_index_--;
1550       PushGpr(handle);
1551     } else {
1552       stack_entries_++;
1553       PushStack(handle);
1554       gpr_index_ = 0;
1555     }
1556   }
1557 
HaveIntGpr() const1558   bool HaveIntGpr() const {
1559     return gpr_index_ > 0;
1560   }
1561 
AdvanceInt(uint32_t val)1562   void AdvanceInt(uint32_t val) {
1563     if (HaveIntGpr()) {
1564       gpr_index_--;
1565       if (kMultiGPRegistersWidened) {
1566         DCHECK_EQ(sizeof(uintptr_t), sizeof(int64_t));
1567         PushGpr(static_cast<int64_t>(bit_cast<int32_t, uint32_t>(val)));
1568       } else {
1569         PushGpr(val);
1570       }
1571     } else {
1572       stack_entries_++;
1573       if (kMultiGPRegistersWidened) {
1574         DCHECK_EQ(sizeof(uintptr_t), sizeof(int64_t));
1575         PushStack(static_cast<int64_t>(bit_cast<int32_t, uint32_t>(val)));
1576       } else {
1577         PushStack(val);
1578       }
1579       gpr_index_ = 0;
1580     }
1581   }
1582 
HaveLongGpr() const1583   bool HaveLongGpr() const {
1584     return gpr_index_ >= kRegistersNeededForLong + (LongGprNeedsPadding() ? 1 : 0);
1585   }
1586 
LongGprNeedsPadding() const1587   bool LongGprNeedsPadding() const {
1588     return kRegistersNeededForLong > 1 &&     // only pad when using multiple registers
1589         kAlignLongOnStack &&                  // and when it needs alignment
1590         (gpr_index_ & 1) == 1;                // counter is odd, see constructor
1591   }
1592 
LongStackNeedsPadding() const1593   bool LongStackNeedsPadding() const {
1594     return kRegistersNeededForLong > 1 &&     // only pad when using multiple registers
1595         kAlignLongOnStack &&                  // and when it needs 8B alignment
1596         (stack_entries_ & 1) == 1;            // counter is odd
1597   }
1598 
AdvanceLong(uint64_t val)1599   void AdvanceLong(uint64_t val) {
1600     if (HaveLongGpr()) {
1601       if (LongGprNeedsPadding()) {
1602         PushGpr(0);
1603         gpr_index_--;
1604       }
1605       if (kRegistersNeededForLong == 1) {
1606         PushGpr(static_cast<uintptr_t>(val));
1607       } else {
1608         PushGpr(static_cast<uintptr_t>(val & 0xFFFFFFFF));
1609         PushGpr(static_cast<uintptr_t>((val >> 32) & 0xFFFFFFFF));
1610       }
1611       gpr_index_ -= kRegistersNeededForLong;
1612     } else {
1613       if (LongStackNeedsPadding()) {
1614         PushStack(0);
1615         stack_entries_++;
1616       }
1617       if (kRegistersNeededForLong == 1) {
1618         PushStack(static_cast<uintptr_t>(val));
1619         stack_entries_++;
1620       } else {
1621         PushStack(static_cast<uintptr_t>(val & 0xFFFFFFFF));
1622         PushStack(static_cast<uintptr_t>((val >> 32) & 0xFFFFFFFF));
1623         stack_entries_ += 2;
1624       }
1625       gpr_index_ = 0;
1626     }
1627   }
1628 
HaveFloatFpr() const1629   bool HaveFloatFpr() const {
1630     return fpr_index_ > 0;
1631   }
1632 
AdvanceFloat(float val)1633   void AdvanceFloat(float val) {
1634     if (kNativeSoftFloatAbi) {
1635       AdvanceInt(bit_cast<uint32_t, float>(val));
1636     } else {
1637       if (HaveFloatFpr()) {
1638         fpr_index_--;
1639         if (kRegistersNeededForDouble == 1) {
1640           if (kMultiFPRegistersWidened) {
1641             PushFpr8(bit_cast<uint64_t, double>(val));
1642           } else {
1643             // No widening, just use the bits.
1644             PushFpr8(static_cast<uint64_t>(bit_cast<uint32_t, float>(val)));
1645           }
1646         } else {
1647           PushFpr4(val);
1648         }
1649       } else {
1650         stack_entries_++;
1651         if (kRegistersNeededForDouble == 1 && kMultiFPRegistersWidened) {
1652           // Need to widen before storing: Note the "double" in the template instantiation.
1653           // Note: We need to jump through those hoops to make the compiler happy.
1654           DCHECK_EQ(sizeof(uintptr_t), sizeof(uint64_t));
1655           PushStack(static_cast<uintptr_t>(bit_cast<uint64_t, double>(val)));
1656         } else {
1657           PushStack(static_cast<uintptr_t>(bit_cast<uint32_t, float>(val)));
1658         }
1659         fpr_index_ = 0;
1660       }
1661     }
1662   }
1663 
HaveDoubleFpr() const1664   bool HaveDoubleFpr() const {
1665     return fpr_index_ >= kRegistersNeededForDouble + (DoubleFprNeedsPadding() ? 1 : 0);
1666   }
1667 
DoubleFprNeedsPadding() const1668   bool DoubleFprNeedsPadding() const {
1669     return kRegistersNeededForDouble > 1 &&     // only pad when using multiple registers
1670         kAlignDoubleOnStack &&                  // and when it needs alignment
1671         (fpr_index_ & 1) == 1;                  // counter is odd, see constructor
1672   }
1673 
DoubleStackNeedsPadding() const1674   bool DoubleStackNeedsPadding() const {
1675     return kRegistersNeededForDouble > 1 &&     // only pad when using multiple registers
1676         kAlignDoubleOnStack &&                  // and when it needs 8B alignment
1677         (stack_entries_ & 1) == 1;              // counter is odd
1678   }
1679 
AdvanceDouble(uint64_t val)1680   void AdvanceDouble(uint64_t val) {
1681     if (kNativeSoftFloatAbi) {
1682       AdvanceLong(val);
1683     } else {
1684       if (HaveDoubleFpr()) {
1685         if (DoubleFprNeedsPadding()) {
1686           PushFpr4(0);
1687           fpr_index_--;
1688         }
1689         PushFpr8(val);
1690         fpr_index_ -= kRegistersNeededForDouble;
1691       } else {
1692         if (DoubleStackNeedsPadding()) {
1693           PushStack(0);
1694           stack_entries_++;
1695         }
1696         if (kRegistersNeededForDouble == 1) {
1697           PushStack(static_cast<uintptr_t>(val));
1698           stack_entries_++;
1699         } else {
1700           PushStack(static_cast<uintptr_t>(val & 0xFFFFFFFF));
1701           PushStack(static_cast<uintptr_t>((val >> 32) & 0xFFFFFFFF));
1702           stack_entries_ += 2;
1703         }
1704         fpr_index_ = 0;
1705       }
1706     }
1707   }
1708 
GetStackEntries() const1709   uint32_t GetStackEntries() const {
1710     return stack_entries_;
1711   }
1712 
GetNumberOfUsedGprs() const1713   uint32_t GetNumberOfUsedGprs() const {
1714     return kNumNativeGprArgs - gpr_index_;
1715   }
1716 
GetNumberOfUsedFprs() const1717   uint32_t GetNumberOfUsedFprs() const {
1718     return kNumNativeFprArgs - fpr_index_;
1719   }
1720 
1721  private:
PushGpr(uintptr_t val)1722   void PushGpr(uintptr_t val) {
1723     delegate_->PushGpr(val);
1724   }
PushFpr4(float val)1725   void PushFpr4(float val) {
1726     delegate_->PushFpr4(val);
1727   }
PushFpr8(uint64_t val)1728   void PushFpr8(uint64_t val) {
1729     delegate_->PushFpr8(val);
1730   }
PushStack(uintptr_t val)1731   void PushStack(uintptr_t val) {
1732     delegate_->PushStack(val);
1733   }
PushHandle(mirror::Object * ref)1734   uintptr_t PushHandle(mirror::Object* ref) REQUIRES_SHARED(Locks::mutator_lock_) {
1735     return delegate_->PushHandle(ref);
1736   }
1737 
1738   uint32_t gpr_index_;      // Number of free GPRs
1739   uint32_t fpr_index_;      // Number of free FPRs
1740   uint32_t stack_entries_;  // Stack entries are in multiples of 32b, as floats are usually not
1741                             // extended
1742   T* const delegate_;             // What Push implementation gets called
1743 };
1744 
1745 // Computes the sizes of register stacks and call stack area. Handling of references can be extended
1746 // in subclasses.
1747 //
1748 // To handle native pointers, use "L" in the shorty for an object reference, which simulates
1749 // them with handles.
1750 class ComputeNativeCallFrameSize {
1751  public:
ComputeNativeCallFrameSize()1752   ComputeNativeCallFrameSize() : num_stack_entries_(0) {}
1753 
~ComputeNativeCallFrameSize()1754   virtual ~ComputeNativeCallFrameSize() {}
1755 
GetStackSize() const1756   uint32_t GetStackSize() const {
1757     return num_stack_entries_ * sizeof(uintptr_t);
1758   }
1759 
LayoutStackArgs(uint8_t * sp8) const1760   uint8_t* LayoutStackArgs(uint8_t* sp8) const {
1761     sp8 -= GetStackSize();
1762     // Align by kStackAlignment; it is at least as strict as native stack alignment.
1763     sp8 = reinterpret_cast<uint8_t*>(RoundDown(reinterpret_cast<uintptr_t>(sp8), kStackAlignment));
1764     return sp8;
1765   }
1766 
WalkHeader(BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize> * sm ATTRIBUTE_UNUSED)1767   virtual void WalkHeader(
1768       BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize>* sm ATTRIBUTE_UNUSED)
1769       REQUIRES_SHARED(Locks::mutator_lock_) {
1770   }
1771 
Walk(const char * shorty,uint32_t shorty_len)1772   void Walk(const char* shorty, uint32_t shorty_len) REQUIRES_SHARED(Locks::mutator_lock_) {
1773     BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize> sm(this);
1774 
1775     WalkHeader(&sm);
1776 
1777     for (uint32_t i = 1; i < shorty_len; ++i) {
1778       Primitive::Type cur_type_ = Primitive::GetType(shorty[i]);
1779       switch (cur_type_) {
1780         case Primitive::kPrimNot:
1781           // TODO: fix abuse of mirror types.
1782           sm.AdvanceHandleScope(
1783               reinterpret_cast<mirror::Object*>(0x12345678));
1784           break;
1785 
1786         case Primitive::kPrimBoolean:
1787         case Primitive::kPrimByte:
1788         case Primitive::kPrimChar:
1789         case Primitive::kPrimShort:
1790         case Primitive::kPrimInt:
1791           sm.AdvanceInt(0);
1792           break;
1793         case Primitive::kPrimFloat:
1794           sm.AdvanceFloat(0);
1795           break;
1796         case Primitive::kPrimDouble:
1797           sm.AdvanceDouble(0);
1798           break;
1799         case Primitive::kPrimLong:
1800           sm.AdvanceLong(0);
1801           break;
1802         default:
1803           LOG(FATAL) << "Unexpected type: " << cur_type_ << " in " << shorty;
1804           UNREACHABLE();
1805       }
1806     }
1807 
1808     num_stack_entries_ = sm.GetStackEntries();
1809   }
1810 
PushGpr(uintptr_t)1811   void PushGpr(uintptr_t /* val */) {
1812     // not optimizing registers, yet
1813   }
1814 
PushFpr4(float)1815   void PushFpr4(float /* val */) {
1816     // not optimizing registers, yet
1817   }
1818 
PushFpr8(uint64_t)1819   void PushFpr8(uint64_t /* val */) {
1820     // not optimizing registers, yet
1821   }
1822 
PushStack(uintptr_t)1823   void PushStack(uintptr_t /* val */) {
1824     // counting is already done in the superclass
1825   }
1826 
PushHandle(mirror::Object *)1827   virtual uintptr_t PushHandle(mirror::Object* /* ptr */) {
1828     return reinterpret_cast<uintptr_t>(nullptr);
1829   }
1830 
1831  protected:
1832   uint32_t num_stack_entries_;
1833 };
1834 
1835 class ComputeGenericJniFrameSize final : public ComputeNativeCallFrameSize {
1836  public:
ComputeGenericJniFrameSize(bool critical_native)1837   explicit ComputeGenericJniFrameSize(bool critical_native)
1838     : num_handle_scope_references_(0), critical_native_(critical_native) {}
1839 
ComputeLayout(Thread * self,ArtMethod ** managed_sp,const char * shorty,uint32_t shorty_len,HandleScope ** handle_scope)1840   uintptr_t* ComputeLayout(Thread* self,
1841                            ArtMethod** managed_sp,
1842                            const char* shorty,
1843                            uint32_t shorty_len,
1844                            HandleScope** handle_scope) REQUIRES_SHARED(Locks::mutator_lock_) {
1845     DCHECK_EQ(Runtime::Current()->GetClassLinker()->GetImagePointerSize(), kRuntimePointerSize);
1846 
1847     Walk(shorty, shorty_len);
1848 
1849     // Add space for cookie and HandleScope.
1850     void* storage = GetGenericJniHandleScope(managed_sp, num_handle_scope_references_);
1851     DCHECK_ALIGNED(storage, sizeof(uintptr_t));
1852     *handle_scope =
1853         HandleScope::Create(storage, self->GetTopHandleScope(), num_handle_scope_references_);
1854     DCHECK_EQ(*handle_scope, storage);
1855     uint8_t* sp8 = reinterpret_cast<uint8_t*>(*handle_scope);
1856     DCHECK_GE(static_cast<size_t>(reinterpret_cast<uint8_t*>(managed_sp) - sp8),
1857               HandleScope::SizeOf(num_handle_scope_references_) + kJniCookieSize);
1858 
1859     // Layout stack arguments.
1860     sp8 = LayoutStackArgs(sp8);
1861 
1862     // Return the new bottom.
1863     DCHECK_ALIGNED(sp8, sizeof(uintptr_t));
1864     return reinterpret_cast<uintptr_t*>(sp8);
1865   }
1866 
GetStartGprRegs(uintptr_t * reserved_area)1867   static uintptr_t* GetStartGprRegs(uintptr_t* reserved_area) {
1868     return reserved_area;
1869   }
1870 
GetStartFprRegs(uintptr_t * reserved_area)1871   static uint32_t* GetStartFprRegs(uintptr_t* reserved_area) {
1872     constexpr size_t num_gprs =
1873         BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize>::kNumNativeGprArgs;
1874     return reinterpret_cast<uint32_t*>(GetStartGprRegs(reserved_area) + num_gprs);
1875   }
1876 
GetHiddenArgSlot(uintptr_t * reserved_area)1877   static uintptr_t* GetHiddenArgSlot(uintptr_t* reserved_area) {
1878     // Note: `num_fprs` is 0 on architectures where sizeof(uintptr_t) does not match the
1879     // FP register size (it is actually 0 on all supported 32-bit architectures).
1880     constexpr size_t num_fprs =
1881         BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize>::kNumNativeFprArgs;
1882     return reinterpret_cast<uintptr_t*>(GetStartFprRegs(reserved_area)) + num_fprs;
1883   }
1884 
GetOutArgsSpSlot(uintptr_t * reserved_area)1885   static uintptr_t* GetOutArgsSpSlot(uintptr_t* reserved_area) {
1886     return GetHiddenArgSlot(reserved_area) + 1;
1887   }
1888 
1889   uintptr_t PushHandle(mirror::Object* /* ptr */) override;
1890 
1891   // Add JNIEnv* and jobj/jclass before the shorty-derived elements.
1892   void WalkHeader(BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize>* sm) override
1893       REQUIRES_SHARED(Locks::mutator_lock_);
1894 
1895  private:
1896   uint32_t num_handle_scope_references_;
1897   const bool critical_native_;
1898 };
1899 
PushHandle(mirror::Object *)1900 uintptr_t ComputeGenericJniFrameSize::PushHandle(mirror::Object* /* ptr */) {
1901   num_handle_scope_references_++;
1902   return reinterpret_cast<uintptr_t>(nullptr);
1903 }
1904 
WalkHeader(BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize> * sm)1905 void ComputeGenericJniFrameSize::WalkHeader(
1906     BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize>* sm) {
1907   // First 2 parameters are always excluded for @CriticalNative.
1908   if (UNLIKELY(critical_native_)) {
1909     return;
1910   }
1911 
1912   // JNIEnv
1913   sm->AdvancePointer(nullptr);
1914 
1915   // Class object or this as first argument
1916   sm->AdvanceHandleScope(reinterpret_cast<mirror::Object*>(0x12345678));
1917 }
1918 
1919 // Class to push values to three separate regions. Used to fill the native call part. Adheres to
1920 // the template requirements of BuildGenericJniFrameStateMachine.
1921 class FillNativeCall {
1922  public:
FillNativeCall(uintptr_t * gpr_regs,uint32_t * fpr_regs,uintptr_t * stack_args)1923   FillNativeCall(uintptr_t* gpr_regs, uint32_t* fpr_regs, uintptr_t* stack_args) :
1924       cur_gpr_reg_(gpr_regs), cur_fpr_reg_(fpr_regs), cur_stack_arg_(stack_args) {}
1925 
~FillNativeCall()1926   virtual ~FillNativeCall() {}
1927 
Reset(uintptr_t * gpr_regs,uint32_t * fpr_regs,uintptr_t * stack_args)1928   void Reset(uintptr_t* gpr_regs, uint32_t* fpr_regs, uintptr_t* stack_args) {
1929     cur_gpr_reg_ = gpr_regs;
1930     cur_fpr_reg_ = fpr_regs;
1931     cur_stack_arg_ = stack_args;
1932   }
1933 
PushGpr(uintptr_t val)1934   void PushGpr(uintptr_t val) {
1935     *cur_gpr_reg_ = val;
1936     cur_gpr_reg_++;
1937   }
1938 
PushFpr4(float val)1939   void PushFpr4(float val) {
1940     *cur_fpr_reg_ = val;
1941     cur_fpr_reg_++;
1942   }
1943 
PushFpr8(uint64_t val)1944   void PushFpr8(uint64_t val) {
1945     uint64_t* tmp = reinterpret_cast<uint64_t*>(cur_fpr_reg_);
1946     *tmp = val;
1947     cur_fpr_reg_ += 2;
1948   }
1949 
PushStack(uintptr_t val)1950   void PushStack(uintptr_t val) {
1951     *cur_stack_arg_ = val;
1952     cur_stack_arg_++;
1953   }
1954 
PushHandle(mirror::Object *)1955   virtual uintptr_t PushHandle(mirror::Object*) REQUIRES_SHARED(Locks::mutator_lock_) {
1956     LOG(FATAL) << "(Non-JNI) Native call does not use handles.";
1957     UNREACHABLE();
1958   }
1959 
1960  private:
1961   uintptr_t* cur_gpr_reg_;
1962   uint32_t* cur_fpr_reg_;
1963   uintptr_t* cur_stack_arg_;
1964 };
1965 
1966 // Visits arguments on the stack placing them into a region lower down the stack for the benefit
1967 // of transitioning into native code.
1968 class BuildGenericJniFrameVisitor final : public QuickArgumentVisitor {
1969  public:
BuildGenericJniFrameVisitor(Thread * self,bool is_static,bool critical_native,const char * shorty,uint32_t shorty_len,ArtMethod ** managed_sp,uintptr_t * reserved_area)1970   BuildGenericJniFrameVisitor(Thread* self,
1971                               bool is_static,
1972                               bool critical_native,
1973                               const char* shorty,
1974                               uint32_t shorty_len,
1975                               ArtMethod** managed_sp,
1976                               uintptr_t* reserved_area)
1977      : QuickArgumentVisitor(managed_sp, is_static, shorty, shorty_len),
1978        jni_call_(nullptr, nullptr, nullptr, nullptr, critical_native),
1979        sm_(&jni_call_) {
1980     DCHECK_ALIGNED(managed_sp, kStackAlignment);
1981     DCHECK_ALIGNED(reserved_area, sizeof(uintptr_t));
1982 
1983     ComputeGenericJniFrameSize fsc(critical_native);
1984     uintptr_t* out_args_sp =
1985         fsc.ComputeLayout(self, managed_sp, shorty, shorty_len, &handle_scope_);
1986 
1987     // Store hidden argument for @CriticalNative.
1988     uintptr_t* hidden_arg_slot = fsc.GetHiddenArgSlot(reserved_area);
1989     constexpr uintptr_t kGenericJniTag = 1u;
1990     ArtMethod* method = *managed_sp;
1991     *hidden_arg_slot = critical_native ? (reinterpret_cast<uintptr_t>(method) | kGenericJniTag)
1992                                        : 0xebad6a89u;  // Bad value.
1993 
1994     // Set out args SP.
1995     uintptr_t* out_args_sp_slot = fsc.GetOutArgsSpSlot(reserved_area);
1996     *out_args_sp_slot = reinterpret_cast<uintptr_t>(out_args_sp);
1997 
1998     jni_call_.Reset(fsc.GetStartGprRegs(reserved_area),
1999                     fsc.GetStartFprRegs(reserved_area),
2000                     out_args_sp,
2001                     handle_scope_);
2002 
2003     // First 2 parameters are always excluded for CriticalNative methods.
2004     if (LIKELY(!critical_native)) {
2005       // jni environment is always first argument
2006       sm_.AdvancePointer(self->GetJniEnv());
2007 
2008       if (is_static) {
2009         sm_.AdvanceHandleScope(method->GetDeclaringClass().Ptr());
2010       }  // else "this" reference is already handled by QuickArgumentVisitor.
2011     }
2012   }
2013 
2014   void Visit() REQUIRES_SHARED(Locks::mutator_lock_) override;
2015 
2016   void FinalizeHandleScope(Thread* self) REQUIRES_SHARED(Locks::mutator_lock_);
2017 
GetFirstHandleScopeEntry()2018   StackReference<mirror::Object>* GetFirstHandleScopeEntry() {
2019     return handle_scope_->GetHandle(0).GetReference();
2020   }
2021 
GetFirstHandleScopeJObject() const2022   jobject GetFirstHandleScopeJObject() const REQUIRES_SHARED(Locks::mutator_lock_) {
2023     return handle_scope_->GetHandle(0).ToJObject();
2024   }
2025 
2026  private:
2027   // A class to fill a JNI call. Adds reference/handle-scope management to FillNativeCall.
2028   class FillJniCall final : public FillNativeCall {
2029    public:
FillJniCall(uintptr_t * gpr_regs,uint32_t * fpr_regs,uintptr_t * stack_args,HandleScope * handle_scope,bool critical_native)2030     FillJniCall(uintptr_t* gpr_regs, uint32_t* fpr_regs, uintptr_t* stack_args,
2031                 HandleScope* handle_scope, bool critical_native)
2032       : FillNativeCall(gpr_regs, fpr_regs, stack_args),
2033                        handle_scope_(handle_scope),
2034         cur_entry_(0),
2035         critical_native_(critical_native) {}
2036 
2037     uintptr_t PushHandle(mirror::Object* ref) override REQUIRES_SHARED(Locks::mutator_lock_);
2038 
Reset(uintptr_t * gpr_regs,uint32_t * fpr_regs,uintptr_t * stack_args,HandleScope * scope)2039     void Reset(uintptr_t* gpr_regs, uint32_t* fpr_regs, uintptr_t* stack_args, HandleScope* scope) {
2040       FillNativeCall::Reset(gpr_regs, fpr_regs, stack_args);
2041       handle_scope_ = scope;
2042       cur_entry_ = 0U;
2043     }
2044 
ResetRemainingScopeSlots()2045     void ResetRemainingScopeSlots() REQUIRES_SHARED(Locks::mutator_lock_) {
2046       // Initialize padding entries.
2047       size_t expected_slots = handle_scope_->NumberOfReferences();
2048       while (cur_entry_ < expected_slots) {
2049         handle_scope_->GetMutableHandle(cur_entry_++).Assign(nullptr);
2050       }
2051 
2052       if (!critical_native_) {
2053         // Non-critical natives have at least the self class (jclass) or this (jobject).
2054         DCHECK_NE(cur_entry_, 0U);
2055       }
2056     }
2057 
CriticalNative() const2058     bool CriticalNative() const {
2059       return critical_native_;
2060     }
2061 
2062    private:
2063     HandleScope* handle_scope_;
2064     size_t cur_entry_;
2065     const bool critical_native_;
2066   };
2067 
2068   HandleScope* handle_scope_;
2069   FillJniCall jni_call_;
2070 
2071   BuildNativeCallFrameStateMachine<FillJniCall> sm_;
2072 
2073   DISALLOW_COPY_AND_ASSIGN(BuildGenericJniFrameVisitor);
2074 };
2075 
PushHandle(mirror::Object * ref)2076 uintptr_t BuildGenericJniFrameVisitor::FillJniCall::PushHandle(mirror::Object* ref) {
2077   uintptr_t tmp;
2078   MutableHandle<mirror::Object> h = handle_scope_->GetMutableHandle(cur_entry_);
2079   h.Assign(ref);
2080   tmp = reinterpret_cast<uintptr_t>(h.ToJObject());
2081   cur_entry_++;
2082   return tmp;
2083 }
2084 
Visit()2085 void BuildGenericJniFrameVisitor::Visit() {
2086   Primitive::Type type = GetParamPrimitiveType();
2087   switch (type) {
2088     case Primitive::kPrimLong: {
2089       jlong long_arg;
2090       if (IsSplitLongOrDouble()) {
2091         long_arg = ReadSplitLongParam();
2092       } else {
2093         long_arg = *reinterpret_cast<jlong*>(GetParamAddress());
2094       }
2095       sm_.AdvanceLong(long_arg);
2096       break;
2097     }
2098     case Primitive::kPrimDouble: {
2099       uint64_t double_arg;
2100       if (IsSplitLongOrDouble()) {
2101         // Read into union so that we don't case to a double.
2102         double_arg = ReadSplitLongParam();
2103       } else {
2104         double_arg = *reinterpret_cast<uint64_t*>(GetParamAddress());
2105       }
2106       sm_.AdvanceDouble(double_arg);
2107       break;
2108     }
2109     case Primitive::kPrimNot: {
2110       StackReference<mirror::Object>* stack_ref =
2111           reinterpret_cast<StackReference<mirror::Object>*>(GetParamAddress());
2112       sm_.AdvanceHandleScope(stack_ref->AsMirrorPtr());
2113       break;
2114     }
2115     case Primitive::kPrimFloat:
2116       sm_.AdvanceFloat(*reinterpret_cast<float*>(GetParamAddress()));
2117       break;
2118     case Primitive::kPrimBoolean:  // Fall-through.
2119     case Primitive::kPrimByte:     // Fall-through.
2120     case Primitive::kPrimChar:     // Fall-through.
2121     case Primitive::kPrimShort:    // Fall-through.
2122     case Primitive::kPrimInt:      // Fall-through.
2123       sm_.AdvanceInt(*reinterpret_cast<jint*>(GetParamAddress()));
2124       break;
2125     case Primitive::kPrimVoid:
2126       LOG(FATAL) << "UNREACHABLE";
2127       UNREACHABLE();
2128   }
2129 }
2130 
FinalizeHandleScope(Thread * self)2131 void BuildGenericJniFrameVisitor::FinalizeHandleScope(Thread* self) {
2132   // Clear out rest of the scope.
2133   jni_call_.ResetRemainingScopeSlots();
2134   if (!jni_call_.CriticalNative()) {
2135     // Install HandleScope.
2136     self->PushHandleScope(handle_scope_);
2137   }
2138 }
2139 
2140 /*
2141  * Initializes the reserved area assumed to be directly below `managed_sp` for a native call:
2142  *
2143  * On entry, the stack has a standard callee-save frame above `managed_sp`,
2144  * and the reserved area below it. Starting below `managed_sp`, we reserve space
2145  * for local reference cookie (not present for @CriticalNative), HandleScope
2146  * (not present for @CriticalNative) and stack args (if args do not fit into
2147  * registers). At the bottom of the reserved area, there is space for register
2148  * arguments, hidden arg (for @CriticalNative) and the SP for the native call
2149  * (i.e. pointer to the stack args area), which the calling stub shall load
2150  * to perform the native call. We fill all these fields, perform class init
2151  * check (for static methods) and/or locking (for synchronized methods) if
2152  * needed and return to the stub.
2153  *
2154  * The return value is the pointer to the native code, null on failure.
2155  */
artQuickGenericJniTrampoline(Thread * self,ArtMethod ** managed_sp,uintptr_t * reserved_area)2156 extern "C" const void* artQuickGenericJniTrampoline(Thread* self,
2157                                                     ArtMethod** managed_sp,
2158                                                     uintptr_t* reserved_area)
2159     REQUIRES_SHARED(Locks::mutator_lock_) {
2160   // Note: We cannot walk the stack properly until fixed up below.
2161   ArtMethod* called = *managed_sp;
2162   DCHECK(called->IsNative()) << called->PrettyMethod(true);
2163   Runtime* runtime = Runtime::Current();
2164   uint32_t shorty_len = 0;
2165   const char* shorty = called->GetShorty(&shorty_len);
2166   bool critical_native = called->IsCriticalNative();
2167   bool fast_native = called->IsFastNative();
2168   bool normal_native = !critical_native && !fast_native;
2169 
2170   // Run the visitor and update sp.
2171   BuildGenericJniFrameVisitor visitor(self,
2172                                       called->IsStatic(),
2173                                       critical_native,
2174                                       shorty,
2175                                       shorty_len,
2176                                       managed_sp,
2177                                       reserved_area);
2178   {
2179     ScopedAssertNoThreadSuspension sants(__FUNCTION__);
2180     visitor.VisitArguments();
2181     // FinalizeHandleScope pushes the handle scope on the thread.
2182     visitor.FinalizeHandleScope(self);
2183   }
2184 
2185   // Fix up managed-stack things in Thread. After this we can walk the stack.
2186   self->SetTopOfStackTagged(managed_sp);
2187 
2188   self->VerifyStack();
2189 
2190   // We can now walk the stack if needed by JIT GC from MethodEntered() for JIT-on-first-use.
2191   jit::Jit* jit = runtime->GetJit();
2192   if (jit != nullptr) {
2193     jit->MethodEntered(self, called);
2194   }
2195 
2196   // We can set the entrypoint of a native method to generic JNI even when the
2197   // class hasn't been initialized, so we need to do the initialization check
2198   // before invoking the native code.
2199   if (NeedsClinitCheckBeforeCall(called)) {
2200     ObjPtr<mirror::Class> declaring_class = called->GetDeclaringClass();
2201     if (UNLIKELY(!declaring_class->IsVisiblyInitialized())) {
2202       // Ensure static method's class is initialized.
2203       StackHandleScope<1> hs(self);
2204       Handle<mirror::Class> h_class(hs.NewHandle(declaring_class));
2205       if (!runtime->GetClassLinker()->EnsureInitialized(self, h_class, true, true)) {
2206         DCHECK(Thread::Current()->IsExceptionPending()) << called->PrettyMethod();
2207         self->PopHandleScope();
2208         return nullptr;  // Report error.
2209       }
2210     }
2211   }
2212 
2213   uint32_t cookie;
2214   uint32_t* sp32;
2215   // Skip calling JniMethodStart for @CriticalNative.
2216   if (LIKELY(!critical_native)) {
2217     // Start JNI, save the cookie.
2218     if (called->IsSynchronized()) {
2219       DCHECK(normal_native) << " @FastNative and synchronize is not supported";
2220       cookie = JniMethodStartSynchronized(visitor.GetFirstHandleScopeJObject(), self);
2221       if (self->IsExceptionPending()) {
2222         self->PopHandleScope();
2223         return nullptr;  // Report error.
2224       }
2225     } else {
2226       if (fast_native) {
2227         cookie = JniMethodFastStart(self);
2228       } else {
2229         DCHECK(normal_native);
2230         cookie = JniMethodStart(self);
2231       }
2232     }
2233     sp32 = reinterpret_cast<uint32_t*>(managed_sp);
2234     *(sp32 - 1) = cookie;
2235   }
2236 
2237   // Retrieve the stored native code.
2238   // Note that it may point to the lookup stub or trampoline.
2239   // FIXME: This is broken for @CriticalNative as the art_jni_dlsym_lookup_stub
2240   // does not handle that case. Calls from compiled stubs are also broken.
2241   void const* nativeCode = called->GetEntryPointFromJni();
2242 
2243   VLOG(third_party_jni) << "GenericJNI: "
2244                         << called->PrettyMethod()
2245                         << " -> "
2246                         << std::hex << reinterpret_cast<uintptr_t>(nativeCode);
2247 
2248   // Return native code.
2249   return nativeCode;
2250 }
2251 
2252 // Defined in quick_jni_entrypoints.cc.
2253 extern uint64_t GenericJniMethodEnd(Thread* self,
2254                                     uint32_t saved_local_ref_cookie,
2255                                     jvalue result,
2256                                     uint64_t result_f,
2257                                     ArtMethod* called);
2258 
2259 /*
2260  * Is called after the native JNI code. Responsible for cleanup (handle scope, saved state) and
2261  * unlocking.
2262  */
artQuickGenericJniEndTrampoline(Thread * self,jvalue result,uint64_t result_f)2263 extern "C" uint64_t artQuickGenericJniEndTrampoline(Thread* self,
2264                                                     jvalue result,
2265                                                     uint64_t result_f) {
2266   // We're here just back from a native call. We don't have the shared mutator lock at this point
2267   // yet until we call GoToRunnable() later in GenericJniMethodEnd(). Accessing objects or doing
2268   // anything that requires a mutator lock before that would cause problems as GC may have the
2269   // exclusive mutator lock and may be moving objects, etc.
2270   ArtMethod** sp = self->GetManagedStack()->GetTopQuickFrame();
2271   DCHECK(self->GetManagedStack()->GetTopQuickFrameTag());
2272   uint32_t* sp32 = reinterpret_cast<uint32_t*>(sp);
2273   ArtMethod* called = *sp;
2274   uint32_t cookie = *(sp32 - 1);
2275   if (kIsDebugBuild && !called->IsCriticalNative()) {
2276     BaseHandleScope* handle_scope = self->GetTopHandleScope();
2277     DCHECK(handle_scope != nullptr);
2278     DCHECK(!handle_scope->IsVariableSized());
2279     // Note: We do not hold mutator lock here for normal JNI, so we cannot use the method's shorty
2280     // to determine the number of references. Instead rely on the value from the HandleScope.
2281     DCHECK_EQ(handle_scope, GetGenericJniHandleScope(sp, handle_scope->NumberOfReferences()));
2282   }
2283   return GenericJniMethodEnd(self, cookie, result, result_f, called);
2284 }
2285 
2286 // We use TwoWordReturn to optimize scalar returns. We use the hi value for code, and the lo value
2287 // for the method pointer.
2288 //
2289 // It is valid to use this, as at the usage points here (returns from C functions) we are assuming
2290 // to hold the mutator lock (see REQUIRES_SHARED(Locks::mutator_lock_) annotations).
2291 
2292 template <InvokeType type, bool access_check>
artInvokeCommon(uint32_t method_idx,ObjPtr<mirror::Object> this_object,Thread * self,ArtMethod ** sp)2293 static TwoWordReturn artInvokeCommon(uint32_t method_idx,
2294                                      ObjPtr<mirror::Object> this_object,
2295                                      Thread* self,
2296                                      ArtMethod** sp) {
2297   ScopedQuickEntrypointChecks sqec(self);
2298   DCHECK_EQ(*sp, Runtime::Current()->GetCalleeSaveMethod(CalleeSaveType::kSaveRefsAndArgs));
2299   ArtMethod* caller_method = QuickArgumentVisitor::GetCallingMethod(sp);
2300   ArtMethod* method = FindMethodFast<type, access_check>(method_idx, this_object, caller_method);
2301   if (UNLIKELY(method == nullptr)) {
2302     const DexFile* dex_file = caller_method->GetDexFile();
2303     uint32_t shorty_len;
2304     const char* shorty = dex_file->GetMethodShorty(dex_file->GetMethodId(method_idx), &shorty_len);
2305     {
2306       // Remember the args in case a GC happens in FindMethodFromCode.
2307       ScopedObjectAccessUnchecked soa(self->GetJniEnv());
2308       RememberForGcArgumentVisitor visitor(sp, type == kStatic, shorty, shorty_len, &soa);
2309       visitor.VisitArguments();
2310       method = FindMethodFromCode<type, access_check>(method_idx,
2311                                                       &this_object,
2312                                                       caller_method,
2313                                                       self);
2314       visitor.FixupReferences();
2315     }
2316 
2317     if (UNLIKELY(method == nullptr)) {
2318       CHECK(self->IsExceptionPending());
2319       return GetTwoWordFailureValue();  // Failure.
2320     }
2321   }
2322   DCHECK(!self->IsExceptionPending());
2323   const void* code = method->GetEntryPointFromQuickCompiledCode();
2324 
2325   // When we return, the caller will branch to this address, so it had better not be 0!
2326   DCHECK(code != nullptr) << "Code was null in method: " << method->PrettyMethod()
2327                           << " location: "
2328                           << method->GetDexFile()->GetLocation();
2329 
2330   return GetTwoWordSuccessValue(reinterpret_cast<uintptr_t>(code),
2331                                 reinterpret_cast<uintptr_t>(method));
2332 }
2333 
2334 // Explicit artInvokeCommon template function declarations to please analysis tool.
2335 #define EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(type, access_check)                                \
2336   template REQUIRES_SHARED(Locks::mutator_lock_)                                          \
2337   TwoWordReturn artInvokeCommon<type, access_check>(                                            \
2338       uint32_t method_idx, ObjPtr<mirror::Object> his_object, Thread* self, ArtMethod** sp)
2339 
2340 EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kVirtual, false);
2341 EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kVirtual, true);
2342 EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kInterface, false);
2343 EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kInterface, true);
2344 EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kDirect, false);
2345 EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kDirect, true);
2346 EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kStatic, false);
2347 EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kStatic, true);
2348 EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kSuper, false);
2349 EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kSuper, true);
2350 #undef EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL
2351 
2352 // See comments in runtime_support_asm.S
artInvokeInterfaceTrampolineWithAccessCheck(uint32_t method_idx,mirror::Object * this_object,Thread * self,ArtMethod ** sp)2353 extern "C" TwoWordReturn artInvokeInterfaceTrampolineWithAccessCheck(
2354     uint32_t method_idx, mirror::Object* this_object, Thread* self, ArtMethod** sp)
2355     REQUIRES_SHARED(Locks::mutator_lock_) {
2356   return artInvokeCommon<kInterface, true>(method_idx, this_object, self, sp);
2357 }
2358 
artInvokeDirectTrampolineWithAccessCheck(uint32_t method_idx,mirror::Object * this_object,Thread * self,ArtMethod ** sp)2359 extern "C" TwoWordReturn artInvokeDirectTrampolineWithAccessCheck(
2360     uint32_t method_idx, mirror::Object* this_object, Thread* self, ArtMethod** sp)
2361     REQUIRES_SHARED(Locks::mutator_lock_) {
2362   return artInvokeCommon<kDirect, true>(method_idx, this_object, self, sp);
2363 }
2364 
artInvokeStaticTrampolineWithAccessCheck(uint32_t method_idx,mirror::Object * this_object ATTRIBUTE_UNUSED,Thread * self,ArtMethod ** sp)2365 extern "C" TwoWordReturn artInvokeStaticTrampolineWithAccessCheck(
2366     uint32_t method_idx,
2367     mirror::Object* this_object ATTRIBUTE_UNUSED,
2368     Thread* self,
2369     ArtMethod** sp) REQUIRES_SHARED(Locks::mutator_lock_) {
2370   // For static, this_object is not required and may be random garbage. Don't pass it down so that
2371   // it doesn't cause ObjPtr alignment failure check.
2372   return artInvokeCommon<kStatic, true>(method_idx, nullptr, self, sp);
2373 }
2374 
artInvokeSuperTrampolineWithAccessCheck(uint32_t method_idx,mirror::Object * this_object,Thread * self,ArtMethod ** sp)2375 extern "C" TwoWordReturn artInvokeSuperTrampolineWithAccessCheck(
2376     uint32_t method_idx, mirror::Object* this_object, Thread* self, ArtMethod** sp)
2377     REQUIRES_SHARED(Locks::mutator_lock_) {
2378   return artInvokeCommon<kSuper, true>(method_idx, this_object, self, sp);
2379 }
2380 
artInvokeVirtualTrampolineWithAccessCheck(uint32_t method_idx,mirror::Object * this_object,Thread * self,ArtMethod ** sp)2381 extern "C" TwoWordReturn artInvokeVirtualTrampolineWithAccessCheck(
2382     uint32_t method_idx, mirror::Object* this_object, Thread* self, ArtMethod** sp)
2383     REQUIRES_SHARED(Locks::mutator_lock_) {
2384   return artInvokeCommon<kVirtual, true>(method_idx, this_object, self, sp);
2385 }
2386 
2387 // Helper function for art_quick_imt_conflict_trampoline to look up the interface method.
artLookupResolvedMethod(uint32_t method_index,ArtMethod * referrer)2388 extern "C" ArtMethod* artLookupResolvedMethod(uint32_t method_index, ArtMethod* referrer)
2389     REQUIRES_SHARED(Locks::mutator_lock_) {
2390   ScopedAssertNoThreadSuspension ants(__FUNCTION__);
2391   DCHECK(!referrer->IsProxyMethod());
2392   ArtMethod* result = Runtime::Current()->GetClassLinker()->LookupResolvedMethod(
2393       method_index, referrer->GetDexCache(), referrer->GetClassLoader());
2394   DCHECK(result == nullptr ||
2395          result->GetDeclaringClass()->IsInterface() ||
2396          result->GetDeclaringClass() ==
2397              WellKnownClasses::ToClass(WellKnownClasses::java_lang_Object))
2398       << result->PrettyMethod();
2399   return result;
2400 }
2401 
2402 // Determine target of interface dispatch. The interface method and this object are known non-null.
2403 // The interface method is the method returned by the dex cache in the conflict trampoline.
artInvokeInterfaceTrampoline(ArtMethod * interface_method,mirror::Object * raw_this_object,Thread * self,ArtMethod ** sp)2404 extern "C" TwoWordReturn artInvokeInterfaceTrampoline(ArtMethod* interface_method,
2405                                                       mirror::Object* raw_this_object,
2406                                                       Thread* self,
2407                                                       ArtMethod** sp)
2408     REQUIRES_SHARED(Locks::mutator_lock_) {
2409   ScopedQuickEntrypointChecks sqec(self);
2410   StackHandleScope<2> hs(self);
2411   Handle<mirror::Object> this_object = hs.NewHandle(raw_this_object);
2412   Handle<mirror::Class> cls = hs.NewHandle(this_object->GetClass());
2413 
2414   ArtMethod* caller_method = QuickArgumentVisitor::GetCallingMethod(sp);
2415   ArtMethod* method = nullptr;
2416   ImTable* imt = cls->GetImt(kRuntimePointerSize);
2417 
2418   if (UNLIKELY(interface_method == nullptr)) {
2419     // The interface method is unresolved, so resolve it in the dex file of the caller.
2420     // Fetch the dex_method_idx of the target interface method from the caller.
2421     uint32_t dex_method_idx;
2422     uint32_t dex_pc = QuickArgumentVisitor::GetCallingDexPc(sp);
2423     const Instruction& instr = caller_method->DexInstructions().InstructionAt(dex_pc);
2424     Instruction::Code instr_code = instr.Opcode();
2425     DCHECK(instr_code == Instruction::INVOKE_INTERFACE ||
2426            instr_code == Instruction::INVOKE_INTERFACE_RANGE)
2427         << "Unexpected call into interface trampoline: " << instr.DumpString(nullptr);
2428     if (instr_code == Instruction::INVOKE_INTERFACE) {
2429       dex_method_idx = instr.VRegB_35c();
2430     } else {
2431       DCHECK_EQ(instr_code, Instruction::INVOKE_INTERFACE_RANGE);
2432       dex_method_idx = instr.VRegB_3rc();
2433     }
2434 
2435     const DexFile& dex_file = *caller_method->GetDexFile();
2436     uint32_t shorty_len;
2437     const char* shorty = dex_file.GetMethodShorty(dex_file.GetMethodId(dex_method_idx),
2438                                                   &shorty_len);
2439     {
2440       // Remember the args in case a GC happens in ClassLinker::ResolveMethod().
2441       ScopedObjectAccessUnchecked soa(self->GetJniEnv());
2442       RememberForGcArgumentVisitor visitor(sp, false, shorty, shorty_len, &soa);
2443       visitor.VisitArguments();
2444       ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
2445       interface_method = class_linker->ResolveMethod<ClassLinker::ResolveMode::kNoChecks>(
2446           self, dex_method_idx, caller_method, kInterface);
2447       visitor.FixupReferences();
2448     }
2449 
2450     if (UNLIKELY(interface_method == nullptr)) {
2451       CHECK(self->IsExceptionPending());
2452       return GetTwoWordFailureValue();  // Failure.
2453     }
2454   }
2455 
2456   // The compiler and interpreter make sure the conflict trampoline is never
2457   // called on a method that resolves to j.l.Object.
2458   CHECK(!interface_method->GetDeclaringClass()->IsObjectClass());
2459   CHECK(interface_method->GetDeclaringClass()->IsInterface());
2460 
2461   DCHECK(!interface_method->IsRuntimeMethod());
2462   // Look whether we have a match in the ImtConflictTable.
2463   uint32_t imt_index = interface_method->GetImtIndex();
2464   ArtMethod* conflict_method = imt->Get(imt_index, kRuntimePointerSize);
2465   if (LIKELY(conflict_method->IsRuntimeMethod())) {
2466     ImtConflictTable* current_table = conflict_method->GetImtConflictTable(kRuntimePointerSize);
2467     DCHECK(current_table != nullptr);
2468     method = current_table->Lookup(interface_method, kRuntimePointerSize);
2469   } else {
2470     // It seems we aren't really a conflict method!
2471     if (kIsDebugBuild) {
2472       ArtMethod* m = cls->FindVirtualMethodForInterface(interface_method, kRuntimePointerSize);
2473       CHECK_EQ(conflict_method, m)
2474           << interface_method->PrettyMethod() << " / " << conflict_method->PrettyMethod() << " / "
2475           << " / " << ArtMethod::PrettyMethod(m) << " / " << cls->PrettyClass();
2476     }
2477     method = conflict_method;
2478   }
2479   if (method != nullptr) {
2480     return GetTwoWordSuccessValue(
2481         reinterpret_cast<uintptr_t>(method->GetEntryPointFromQuickCompiledCode()),
2482         reinterpret_cast<uintptr_t>(method));
2483   }
2484 
2485   // No match, use the IfTable.
2486   method = cls->FindVirtualMethodForInterface(interface_method, kRuntimePointerSize);
2487   if (UNLIKELY(method == nullptr)) {
2488     ThrowIncompatibleClassChangeErrorClassForInterfaceDispatch(
2489         interface_method, this_object.Get(), caller_method);
2490     return GetTwoWordFailureValue();  // Failure.
2491   }
2492 
2493   // We arrive here if we have found an implementation, and it is not in the ImtConflictTable.
2494   // We create a new table with the new pair { interface_method, method }.
2495   DCHECK(conflict_method->IsRuntimeMethod());
2496   ArtMethod* new_conflict_method = Runtime::Current()->GetClassLinker()->AddMethodToConflictTable(
2497       cls.Get(),
2498       conflict_method,
2499       interface_method,
2500       method,
2501       /*force_new_conflict_method=*/false);
2502   if (new_conflict_method != conflict_method) {
2503     // Update the IMT if we create a new conflict method. No fence needed here, as the
2504     // data is consistent.
2505     imt->Set(imt_index,
2506              new_conflict_method,
2507              kRuntimePointerSize);
2508   }
2509 
2510   const void* code = method->GetEntryPointFromQuickCompiledCode();
2511 
2512   // When we return, the caller will branch to this address, so it had better not be 0!
2513   DCHECK(code != nullptr) << "Code was null in method: " << method->PrettyMethod()
2514                           << " location: " << method->GetDexFile()->GetLocation();
2515 
2516   return GetTwoWordSuccessValue(reinterpret_cast<uintptr_t>(code),
2517                                 reinterpret_cast<uintptr_t>(method));
2518 }
2519 
2520 // Returns uint64_t representing raw bits from JValue.
artInvokePolymorphic(mirror::Object * raw_receiver,Thread * self,ArtMethod ** sp)2521 extern "C" uint64_t artInvokePolymorphic(mirror::Object* raw_receiver, Thread* self, ArtMethod** sp)
2522     REQUIRES_SHARED(Locks::mutator_lock_) {
2523   ScopedQuickEntrypointChecks sqec(self);
2524   DCHECK(raw_receiver != nullptr);
2525   DCHECK_EQ(*sp, Runtime::Current()->GetCalleeSaveMethod(CalleeSaveType::kSaveRefsAndArgs));
2526 
2527   // Start new JNI local reference state
2528   JNIEnvExt* env = self->GetJniEnv();
2529   ScopedObjectAccessUnchecked soa(env);
2530   ScopedJniEnvLocalRefState env_state(env);
2531   const char* old_cause = self->StartAssertNoThreadSuspension("Making stack arguments safe.");
2532 
2533   // From the instruction, get the |callsite_shorty| and expose arguments on the stack to the GC.
2534   ArtMethod* caller_method = QuickArgumentVisitor::GetCallingMethod(sp);
2535   uint32_t dex_pc = QuickArgumentVisitor::GetCallingDexPc(sp);
2536   const Instruction& inst = caller_method->DexInstructions().InstructionAt(dex_pc);
2537   DCHECK(inst.Opcode() == Instruction::INVOKE_POLYMORPHIC ||
2538          inst.Opcode() == Instruction::INVOKE_POLYMORPHIC_RANGE);
2539   const dex::ProtoIndex proto_idx(inst.VRegH());
2540   const char* shorty = caller_method->GetDexFile()->GetShorty(proto_idx);
2541   const size_t shorty_length = strlen(shorty);
2542   static const bool kMethodIsStatic = false;  // invoke() and invokeExact() are not static.
2543   RememberForGcArgumentVisitor gc_visitor(sp, kMethodIsStatic, shorty, shorty_length, &soa);
2544   gc_visitor.VisitArguments();
2545 
2546   // Wrap raw_receiver in a Handle for safety.
2547   StackHandleScope<3> hs(self);
2548   Handle<mirror::Object> receiver_handle(hs.NewHandle(raw_receiver));
2549   raw_receiver = nullptr;
2550   self->EndAssertNoThreadSuspension(old_cause);
2551 
2552   // Resolve method.
2553   ClassLinker* linker = Runtime::Current()->GetClassLinker();
2554   ArtMethod* resolved_method = linker->ResolveMethod<ClassLinker::ResolveMode::kCheckICCEAndIAE>(
2555       self, inst.VRegB(), caller_method, kVirtual);
2556 
2557   Handle<mirror::MethodType> method_type(
2558       hs.NewHandle(linker->ResolveMethodType(self, proto_idx, caller_method)));
2559   if (UNLIKELY(method_type.IsNull())) {
2560     // This implies we couldn't resolve one or more types in this method handle.
2561     CHECK(self->IsExceptionPending());
2562     return 0UL;
2563   }
2564 
2565   DCHECK_EQ(ArtMethod::NumArgRegisters(shorty) + 1u, (uint32_t)inst.VRegA());
2566   DCHECK_EQ(resolved_method->IsStatic(), kMethodIsStatic);
2567 
2568   // Fix references before constructing the shadow frame.
2569   gc_visitor.FixupReferences();
2570 
2571   // Construct shadow frame placing arguments consecutively from |first_arg|.
2572   const bool is_range = (inst.Opcode() == Instruction::INVOKE_POLYMORPHIC_RANGE);
2573   const size_t num_vregs = is_range ? inst.VRegA_4rcc() : inst.VRegA_45cc();
2574   const size_t first_arg = 0;
2575   ShadowFrameAllocaUniquePtr shadow_frame_unique_ptr =
2576       CREATE_SHADOW_FRAME(num_vregs, /* link= */ nullptr, resolved_method, dex_pc);
2577   ShadowFrame* shadow_frame = shadow_frame_unique_ptr.get();
2578   ScopedStackedShadowFramePusher
2579       frame_pusher(self, shadow_frame, StackedShadowFrameType::kShadowFrameUnderConstruction);
2580   BuildQuickShadowFrameVisitor shadow_frame_builder(sp,
2581                                                     kMethodIsStatic,
2582                                                     shorty,
2583                                                     strlen(shorty),
2584                                                     shadow_frame,
2585                                                     first_arg);
2586   shadow_frame_builder.VisitArguments();
2587 
2588   // Push a transition back into managed code onto the linked list in thread.
2589   ManagedStack fragment;
2590   self->PushManagedStackFragment(&fragment);
2591 
2592   // Call DoInvokePolymorphic with |is_range| = true, as shadow frame has argument registers in
2593   // consecutive order.
2594   RangeInstructionOperands operands(first_arg + 1, num_vregs - 1);
2595   Intrinsics intrinsic = static_cast<Intrinsics>(resolved_method->GetIntrinsic());
2596   JValue result;
2597   bool success = false;
2598   if (resolved_method->GetDeclaringClass() == GetClassRoot<mirror::MethodHandle>(linker)) {
2599     Handle<mirror::MethodHandle> method_handle(hs.NewHandle(
2600         ObjPtr<mirror::MethodHandle>::DownCast(receiver_handle.Get())));
2601     if (intrinsic == Intrinsics::kMethodHandleInvokeExact) {
2602       success = MethodHandleInvokeExact(self,
2603                                         *shadow_frame,
2604                                         method_handle,
2605                                         method_type,
2606                                         &operands,
2607                                         &result);
2608     } else {
2609       DCHECK_EQ(static_cast<uint32_t>(intrinsic),
2610                 static_cast<uint32_t>(Intrinsics::kMethodHandleInvoke));
2611       success = MethodHandleInvoke(self,
2612                                    *shadow_frame,
2613                                    method_handle,
2614                                    method_type,
2615                                    &operands,
2616                                    &result);
2617     }
2618   } else {
2619     DCHECK_EQ(GetClassRoot<mirror::VarHandle>(linker), resolved_method->GetDeclaringClass());
2620     Handle<mirror::VarHandle> var_handle(hs.NewHandle(
2621         ObjPtr<mirror::VarHandle>::DownCast(receiver_handle.Get())));
2622     mirror::VarHandle::AccessMode access_mode =
2623         mirror::VarHandle::GetAccessModeByIntrinsic(intrinsic);
2624     success = VarHandleInvokeAccessor(self,
2625                                       *shadow_frame,
2626                                       var_handle,
2627                                       method_type,
2628                                       access_mode,
2629                                       &operands,
2630                                       &result);
2631   }
2632 
2633   DCHECK(success || self->IsExceptionPending());
2634 
2635   // Pop transition record.
2636   self->PopManagedStackFragment(fragment);
2637 
2638   return result.GetJ();
2639 }
2640 
2641 // Returns uint64_t representing raw bits from JValue.
artInvokeCustom(uint32_t call_site_idx,Thread * self,ArtMethod ** sp)2642 extern "C" uint64_t artInvokeCustom(uint32_t call_site_idx, Thread* self, ArtMethod** sp)
2643     REQUIRES_SHARED(Locks::mutator_lock_) {
2644   ScopedQuickEntrypointChecks sqec(self);
2645   DCHECK_EQ(*sp, Runtime::Current()->GetCalleeSaveMethod(CalleeSaveType::kSaveRefsAndArgs));
2646 
2647   // invoke-custom is effectively a static call (no receiver).
2648   static constexpr bool kMethodIsStatic = true;
2649 
2650   // Start new JNI local reference state
2651   JNIEnvExt* env = self->GetJniEnv();
2652   ScopedObjectAccessUnchecked soa(env);
2653   ScopedJniEnvLocalRefState env_state(env);
2654 
2655   const char* old_cause = self->StartAssertNoThreadSuspension("Making stack arguments safe.");
2656 
2657   // From the instruction, get the |callsite_shorty| and expose arguments on the stack to the GC.
2658   ArtMethod* caller_method = QuickArgumentVisitor::GetCallingMethod(sp);
2659   uint32_t dex_pc = QuickArgumentVisitor::GetCallingDexPc(sp);
2660   const DexFile* dex_file = caller_method->GetDexFile();
2661   const dex::ProtoIndex proto_idx(dex_file->GetProtoIndexForCallSite(call_site_idx));
2662   const char* shorty = caller_method->GetDexFile()->GetShorty(proto_idx);
2663   const uint32_t shorty_len = strlen(shorty);
2664 
2665   // Construct the shadow frame placing arguments consecutively from |first_arg|.
2666   const size_t first_arg = 0;
2667   const size_t num_vregs = ArtMethod::NumArgRegisters(shorty);
2668   ShadowFrameAllocaUniquePtr shadow_frame_unique_ptr =
2669       CREATE_SHADOW_FRAME(num_vregs, /* link= */ nullptr, caller_method, dex_pc);
2670   ShadowFrame* shadow_frame = shadow_frame_unique_ptr.get();
2671   ScopedStackedShadowFramePusher
2672       frame_pusher(self, shadow_frame, StackedShadowFrameType::kShadowFrameUnderConstruction);
2673   BuildQuickShadowFrameVisitor shadow_frame_builder(sp,
2674                                                     kMethodIsStatic,
2675                                                     shorty,
2676                                                     shorty_len,
2677                                                     shadow_frame,
2678                                                     first_arg);
2679   shadow_frame_builder.VisitArguments();
2680 
2681   // Push a transition back into managed code onto the linked list in thread.
2682   ManagedStack fragment;
2683   self->PushManagedStackFragment(&fragment);
2684   self->EndAssertNoThreadSuspension(old_cause);
2685 
2686   // Perform the invoke-custom operation.
2687   RangeInstructionOperands operands(first_arg, num_vregs);
2688   JValue result;
2689   bool success =
2690       interpreter::DoInvokeCustom(self, *shadow_frame, call_site_idx, &operands, &result);
2691   DCHECK(success || self->IsExceptionPending());
2692 
2693   // Pop transition record.
2694   self->PopManagedStackFragment(fragment);
2695 
2696   return result.GetJ();
2697 }
2698 
2699 }  // namespace art
2700