quick_trampoline_entrypoints.cc revision 0398e171f206cd3b140a358ac31b0a3760380df1
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 "callee_save_frame.h"
18#include "common_throws.h"
19#include "dex_file-inl.h"
20#include "dex_instruction-inl.h"
21#include "entrypoints/entrypoint_utils-inl.h"
22#include "gc/accounting/card_table-inl.h"
23#include "instruction_set.h"
24#include "interpreter/interpreter.h"
25#include "mirror/art_method-inl.h"
26#include "mirror/class-inl.h"
27#include "mirror/dex_cache-inl.h"
28#include "mirror/object-inl.h"
29#include "mirror/object_array-inl.h"
30#include "runtime.h"
31#include "scoped_thread_state_change.h"
32
33namespace art {
34
35// Visits the arguments as saved to the stack by a Runtime::kRefAndArgs callee save frame.
36class QuickArgumentVisitor {
37  // Number of bytes for each out register in the caller method's frame.
38  static constexpr size_t kBytesStackArgLocation = 4;
39  // Frame size in bytes of a callee-save frame for RefsAndArgs.
40  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_FrameSize =
41      GetCalleeSaveFrameSize(kRuntimeISA, Runtime::kRefsAndArgs);
42#if defined(__arm__)
43  // The callee save frame is pointed to by SP.
44  // | argN       |  |
45  // | ...        |  |
46  // | arg4       |  |
47  // | arg3 spill |  |  Caller's frame
48  // | arg2 spill |  |
49  // | arg1 spill |  |
50  // | Method*    | ---
51  // | LR         |
52  // | ...        |    callee saves
53  // | R3         |    arg3
54  // | R2         |    arg2
55  // | R1         |    arg1
56  // | R0         |    padding
57  // | Method*    |  <- sp
58  static constexpr bool kQuickSoftFloatAbi = true;  // This is a soft float ABI.
59  static constexpr size_t kNumQuickGprArgs = 3;  // 3 arguments passed in GPRs.
60  static constexpr size_t kNumQuickFprArgs = 0;  // 0 arguments passed in FPRs.
61  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_Fpr1Offset = 0;  // Offset of first FPR arg.
62  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_Gpr1Offset = 8;  // Offset of first GPR arg.
63  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_LrOffset = 44;  // Offset of return address.
64  static size_t GprIndexToGprOffset(uint32_t gpr_index) {
65    return gpr_index * GetBytesPerGprSpillLocation(kRuntimeISA);
66  }
67#elif defined(__aarch64__)
68  // The callee save frame is pointed to by SP.
69  // | argN       |  |
70  // | ...        |  |
71  // | arg4       |  |
72  // | arg3 spill |  |  Caller's frame
73  // | arg2 spill |  |
74  // | arg1 spill |  |
75  // | Method*    | ---
76  // | LR         |
77  // | X28        |
78  // |  :         |
79  // | X19        |
80  // | X7         |
81  // | :          |
82  // | X1         |
83  // | D15        |
84  // |  :         |
85  // | D0         |
86  // |            |    padding
87  // | Method*    |  <- sp
88  static constexpr bool kQuickSoftFloatAbi = false;  // This is a hard float ABI.
89  static constexpr size_t kNumQuickGprArgs = 7;  // 7 arguments passed in GPRs.
90  static constexpr size_t kNumQuickFprArgs = 8;  // 8 arguments passed in FPRs.
91  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_Fpr1Offset = 16;  // Offset of first FPR arg.
92  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_Gpr1Offset = 144;  // Offset of first GPR arg.
93  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_LrOffset = 296;  // Offset of return address.
94  static size_t GprIndexToGprOffset(uint32_t gpr_index) {
95    return gpr_index * GetBytesPerGprSpillLocation(kRuntimeISA);
96  }
97#elif defined(__mips__)
98  // The callee save frame is pointed to by SP.
99  // | argN       |  |
100  // | ...        |  |
101  // | arg4       |  |
102  // | arg3 spill |  |  Caller's frame
103  // | arg2 spill |  |
104  // | arg1 spill |  |
105  // | Method*    | ---
106  // | RA         |
107  // | ...        |    callee saves
108  // | A3         |    arg3
109  // | A2         |    arg2
110  // | A1         |    arg1
111  // | A0/Method* |  <- sp
112  static constexpr bool kQuickSoftFloatAbi = true;  // This is a soft float ABI.
113  static constexpr size_t kNumQuickGprArgs = 3;  // 3 arguments passed in GPRs.
114  static constexpr size_t kNumQuickFprArgs = 0;  // 0 arguments passed in FPRs.
115  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_Fpr1Offset = 0;  // Offset of first FPR arg.
116  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_Gpr1Offset = 4;  // Offset of first GPR arg.
117  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_LrOffset = 60;  // Offset of return address.
118  static size_t GprIndexToGprOffset(uint32_t gpr_index) {
119    return gpr_index * GetBytesPerGprSpillLocation(kRuntimeISA);
120  }
121#elif defined(__i386__)
122  // The callee save frame is pointed to by SP.
123  // | argN        |  |
124  // | ...         |  |
125  // | arg4        |  |
126  // | arg3 spill  |  |  Caller's frame
127  // | arg2 spill  |  |
128  // | arg1 spill  |  |
129  // | Method*     | ---
130  // | Return      |
131  // | EBP,ESI,EDI |    callee saves
132  // | EBX         |    arg3
133  // | EDX         |    arg2
134  // | ECX         |    arg1
135  // | EAX/Method* |  <- sp
136  static constexpr bool kQuickSoftFloatAbi = true;  // This is a soft float ABI.
137  static constexpr size_t kNumQuickGprArgs = 3;  // 3 arguments passed in GPRs.
138  static constexpr size_t kNumQuickFprArgs = 0;  // 0 arguments passed in FPRs.
139  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_Fpr1Offset = 0;  // Offset of first FPR arg.
140  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_Gpr1Offset = 4;  // Offset of first GPR arg.
141  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_LrOffset = 28;  // Offset of return address.
142  static size_t GprIndexToGprOffset(uint32_t gpr_index) {
143    return gpr_index * GetBytesPerGprSpillLocation(kRuntimeISA);
144  }
145#elif defined(__x86_64__)
146  // The callee save frame is pointed to by SP.
147  // | argN            |  |
148  // | ...             |  |
149  // | reg. arg spills |  |  Caller's frame
150  // | Method*         | ---
151  // | Return          |
152  // | R15             |    callee save
153  // | R14             |    callee save
154  // | R13             |    callee save
155  // | R12             |    callee save
156  // | R9              |    arg5
157  // | R8              |    arg4
158  // | RSI/R6          |    arg1
159  // | RBP/R5          |    callee save
160  // | RBX/R3          |    callee save
161  // | RDX/R2          |    arg2
162  // | RCX/R1          |    arg3
163  // | XMM7            |    float arg 8
164  // | XMM6            |    float arg 7
165  // | XMM5            |    float arg 6
166  // | XMM4            |    float arg 5
167  // | XMM3            |    float arg 4
168  // | XMM2            |    float arg 3
169  // | XMM1            |    float arg 2
170  // | XMM0            |    float arg 1
171  // | Padding         |
172  // | RDI/Method*     |  <- sp
173  static constexpr bool kQuickSoftFloatAbi = false;  // This is a hard float ABI.
174  static constexpr size_t kNumQuickGprArgs = 5;  // 5 arguments passed in GPRs.
175  static constexpr size_t kNumQuickFprArgs = 8;  // 8 arguments passed in FPRs.
176  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_Fpr1Offset = 16;  // Offset of first FPR arg.
177  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_Gpr1Offset = 80 + 4*8;  // Offset of first GPR arg.
178  static constexpr size_t kQuickCalleeSaveFrame_RefAndArgs_LrOffset = 168 + 4*8;  // Offset of return address.
179  static size_t GprIndexToGprOffset(uint32_t gpr_index) {
180    switch (gpr_index) {
181      case 0: return (4 * GetBytesPerGprSpillLocation(kRuntimeISA));
182      case 1: return (1 * GetBytesPerGprSpillLocation(kRuntimeISA));
183      case 2: return (0 * GetBytesPerGprSpillLocation(kRuntimeISA));
184      case 3: return (5 * GetBytesPerGprSpillLocation(kRuntimeISA));
185      case 4: return (6 * GetBytesPerGprSpillLocation(kRuntimeISA));
186      default:
187      LOG(FATAL) << "Unexpected GPR index: " << gpr_index;
188      return 0;
189    }
190  }
191#else
192#error "Unsupported architecture"
193#endif
194
195 public:
196  static mirror::ArtMethod* GetCallingMethod(StackReference<mirror::ArtMethod>* sp)
197      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
198    DCHECK(sp->AsMirrorPtr()->IsCalleeSaveMethod());
199    byte* previous_sp = reinterpret_cast<byte*>(sp) + kQuickCalleeSaveFrame_RefAndArgs_FrameSize;
200    return reinterpret_cast<StackReference<mirror::ArtMethod>*>(previous_sp)->AsMirrorPtr();
201  }
202
203  // For the given quick ref and args quick frame, return the caller's PC.
204  static uintptr_t GetCallingPc(StackReference<mirror::ArtMethod>* sp)
205      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
206    DCHECK(sp->AsMirrorPtr()->IsCalleeSaveMethod());
207    byte* lr = reinterpret_cast<byte*>(sp) + kQuickCalleeSaveFrame_RefAndArgs_LrOffset;
208    return *reinterpret_cast<uintptr_t*>(lr);
209  }
210
211  QuickArgumentVisitor(StackReference<mirror::ArtMethod>* sp, bool is_static, const char* shorty,
212                       uint32_t shorty_len) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) :
213          is_static_(is_static), shorty_(shorty), shorty_len_(shorty_len),
214          gpr_args_(reinterpret_cast<byte*>(sp) + kQuickCalleeSaveFrame_RefAndArgs_Gpr1Offset),
215          fpr_args_(reinterpret_cast<byte*>(sp) + kQuickCalleeSaveFrame_RefAndArgs_Fpr1Offset),
216          stack_args_(reinterpret_cast<byte*>(sp) + kQuickCalleeSaveFrame_RefAndArgs_FrameSize
217                      + StackArgumentStartFromShorty(is_static, shorty, shorty_len)),
218          gpr_index_(0), fpr_index_(0), stack_index_(0), cur_type_(Primitive::kPrimVoid),
219          is_split_long_or_double_(false) {}
220
221  virtual ~QuickArgumentVisitor() {}
222
223  virtual void Visit() = 0;
224
225  Primitive::Type GetParamPrimitiveType() const {
226    return cur_type_;
227  }
228
229  byte* GetParamAddress() const {
230    if (!kQuickSoftFloatAbi) {
231      Primitive::Type type = GetParamPrimitiveType();
232      if (UNLIKELY((type == Primitive::kPrimDouble) || (type == Primitive::kPrimFloat))) {
233        if ((kNumQuickFprArgs != 0) && (fpr_index_ + 1 < kNumQuickFprArgs + 1)) {
234          return fpr_args_ + (fpr_index_ * GetBytesPerFprSpillLocation(kRuntimeISA));
235        }
236        return stack_args_ + (stack_index_ * kBytesStackArgLocation);
237      }
238    }
239    if (gpr_index_ < kNumQuickGprArgs) {
240      return gpr_args_ + GprIndexToGprOffset(gpr_index_);
241    }
242    return stack_args_ + (stack_index_ * kBytesStackArgLocation);
243  }
244
245  bool IsSplitLongOrDouble() const {
246    if ((GetBytesPerGprSpillLocation(kRuntimeISA) == 4) || (GetBytesPerFprSpillLocation(kRuntimeISA) == 4)) {
247      return is_split_long_or_double_;
248    } else {
249      return false;  // An optimization for when GPR and FPRs are 64bit.
250    }
251  }
252
253  bool IsParamAReference() const {
254    return GetParamPrimitiveType() == Primitive::kPrimNot;
255  }
256
257  bool IsParamALongOrDouble() const {
258    Primitive::Type type = GetParamPrimitiveType();
259    return type == Primitive::kPrimLong || type == Primitive::kPrimDouble;
260  }
261
262  uint64_t ReadSplitLongParam() const {
263    DCHECK(IsSplitLongOrDouble());
264    uint64_t low_half = *reinterpret_cast<uint32_t*>(GetParamAddress());
265    uint64_t high_half = *reinterpret_cast<uint32_t*>(stack_args_);
266    return (low_half & 0xffffffffULL) | (high_half << 32);
267  }
268
269  void VisitArguments() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
270    // This implementation doesn't support reg-spill area for hard float
271    // ABI targets such as x86_64 and aarch64. So, for those targets whose
272    // 'kQuickSoftFloatAbi' is 'false':
273    //     (a) 'stack_args_' should point to the first method's argument
274    //     (b) whatever the argument type it is, the 'stack_index_' should
275    //         be moved forward along with every visiting.
276    gpr_index_ = 0;
277    fpr_index_ = 0;
278    stack_index_ = 0;
279    if (!is_static_) {  // Handle this.
280      cur_type_ = Primitive::kPrimNot;
281      is_split_long_or_double_ = false;
282      Visit();
283      if (!kQuickSoftFloatAbi || kNumQuickGprArgs == 0) {
284        stack_index_++;
285      }
286      if (kNumQuickGprArgs > 0) {
287        gpr_index_++;
288      }
289    }
290    for (uint32_t shorty_index = 1; shorty_index < shorty_len_; ++shorty_index) {
291      cur_type_ = Primitive::GetType(shorty_[shorty_index]);
292      switch (cur_type_) {
293        case Primitive::kPrimNot:
294        case Primitive::kPrimBoolean:
295        case Primitive::kPrimByte:
296        case Primitive::kPrimChar:
297        case Primitive::kPrimShort:
298        case Primitive::kPrimInt:
299          is_split_long_or_double_ = false;
300          Visit();
301          if (!kQuickSoftFloatAbi || kNumQuickGprArgs == gpr_index_) {
302            stack_index_++;
303          }
304          if (gpr_index_ < kNumQuickGprArgs) {
305            gpr_index_++;
306          }
307          break;
308        case Primitive::kPrimFloat:
309          is_split_long_or_double_ = false;
310          Visit();
311          if (kQuickSoftFloatAbi) {
312            if (gpr_index_ < kNumQuickGprArgs) {
313              gpr_index_++;
314            } else {
315              stack_index_++;
316            }
317          } else {
318            if ((kNumQuickFprArgs != 0) && (fpr_index_ + 1 < kNumQuickFprArgs + 1)) {
319              fpr_index_++;
320            }
321            stack_index_++;
322          }
323          break;
324        case Primitive::kPrimDouble:
325        case Primitive::kPrimLong:
326          if (kQuickSoftFloatAbi || (cur_type_ == Primitive::kPrimLong)) {
327            is_split_long_or_double_ = (GetBytesPerGprSpillLocation(kRuntimeISA) == 4) &&
328                ((gpr_index_ + 1) == kNumQuickGprArgs);
329            Visit();
330            if (!kQuickSoftFloatAbi || kNumQuickGprArgs == gpr_index_) {
331              if (kBytesStackArgLocation == 4) {
332                stack_index_+= 2;
333              } else {
334                CHECK_EQ(kBytesStackArgLocation, 8U);
335                stack_index_++;
336              }
337            }
338            if (gpr_index_ < kNumQuickGprArgs) {
339              gpr_index_++;
340              if (GetBytesPerGprSpillLocation(kRuntimeISA) == 4) {
341                if (gpr_index_ < kNumQuickGprArgs) {
342                  gpr_index_++;
343                } else if (kQuickSoftFloatAbi) {
344                  stack_index_++;
345                }
346              }
347            }
348          } else {
349            is_split_long_or_double_ = (GetBytesPerFprSpillLocation(kRuntimeISA) == 4) &&
350                ((fpr_index_ + 1) == kNumQuickFprArgs);
351            Visit();
352            if ((kNumQuickFprArgs != 0) && (fpr_index_ + 1 < kNumQuickFprArgs + 1)) {
353              fpr_index_++;
354              if (GetBytesPerFprSpillLocation(kRuntimeISA) == 4) {
355                if ((kNumQuickFprArgs != 0) && (fpr_index_ + 1 < kNumQuickFprArgs + 1)) {
356                  fpr_index_++;
357                }
358              }
359            }
360            if (kBytesStackArgLocation == 4) {
361              stack_index_+= 2;
362            } else {
363              CHECK_EQ(kBytesStackArgLocation, 8U);
364              stack_index_++;
365            }
366          }
367          break;
368        default:
369          LOG(FATAL) << "Unexpected type: " << cur_type_ << " in " << shorty_;
370      }
371    }
372  }
373
374 private:
375  static size_t StackArgumentStartFromShorty(bool is_static, const char* shorty,
376                                             uint32_t shorty_len) {
377    if (kQuickSoftFloatAbi) {
378      CHECK_EQ(kNumQuickFprArgs, 0U);
379      return (kNumQuickGprArgs * GetBytesPerGprSpillLocation(kRuntimeISA))
380          + sizeof(StackReference<mirror::ArtMethod>) /* StackReference<ArtMethod> */;
381    } else {
382      // For now, there is no reg-spill area for the targets with
383      // hard float ABI. So, the offset pointing to the first method's
384      // parameter ('this' for non-static methods) should be returned.
385      return sizeof(StackReference<mirror::ArtMethod>);  // Skip StackReference<ArtMethod>.
386    }
387  }
388
389 protected:
390  const bool is_static_;
391  const char* const shorty_;
392  const uint32_t shorty_len_;
393
394 private:
395  byte* const gpr_args_;  // Address of GPR arguments in callee save frame.
396  byte* const fpr_args_;  // Address of FPR arguments in callee save frame.
397  byte* const stack_args_;  // Address of stack arguments in caller's frame.
398  uint32_t gpr_index_;  // Index into spilled GPRs.
399  uint32_t fpr_index_;  // Index into spilled FPRs.
400  uint32_t stack_index_;  // Index into arguments on the stack.
401  // The current type of argument during VisitArguments.
402  Primitive::Type cur_type_;
403  // Does a 64bit parameter straddle the register and stack arguments?
404  bool is_split_long_or_double_;
405};
406
407// Visits arguments on the stack placing them into the shadow frame.
408class BuildQuickShadowFrameVisitor FINAL : public QuickArgumentVisitor {
409 public:
410  BuildQuickShadowFrameVisitor(StackReference<mirror::ArtMethod>* sp, bool is_static,
411                               const char* shorty, uint32_t shorty_len, ShadowFrame* sf,
412                               size_t first_arg_reg) :
413      QuickArgumentVisitor(sp, is_static, shorty, shorty_len), sf_(sf), cur_reg_(first_arg_reg) {}
414
415  void Visit() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) OVERRIDE;
416
417 private:
418  ShadowFrame* const sf_;
419  uint32_t cur_reg_;
420
421  DISALLOW_COPY_AND_ASSIGN(BuildQuickShadowFrameVisitor);
422};
423
424void BuildQuickShadowFrameVisitor::Visit() {
425  Primitive::Type type = GetParamPrimitiveType();
426  switch (type) {
427    case Primitive::kPrimLong:  // Fall-through.
428    case Primitive::kPrimDouble:
429      if (IsSplitLongOrDouble()) {
430        sf_->SetVRegLong(cur_reg_, ReadSplitLongParam());
431      } else {
432        sf_->SetVRegLong(cur_reg_, *reinterpret_cast<jlong*>(GetParamAddress()));
433      }
434      ++cur_reg_;
435      break;
436    case Primitive::kPrimNot: {
437        StackReference<mirror::Object>* stack_ref =
438            reinterpret_cast<StackReference<mirror::Object>*>(GetParamAddress());
439        sf_->SetVRegReference(cur_reg_, stack_ref->AsMirrorPtr());
440      }
441      break;
442    case Primitive::kPrimBoolean:  // Fall-through.
443    case Primitive::kPrimByte:     // Fall-through.
444    case Primitive::kPrimChar:     // Fall-through.
445    case Primitive::kPrimShort:    // Fall-through.
446    case Primitive::kPrimInt:      // Fall-through.
447    case Primitive::kPrimFloat:
448      sf_->SetVReg(cur_reg_, *reinterpret_cast<jint*>(GetParamAddress()));
449      break;
450    case Primitive::kPrimVoid:
451      LOG(FATAL) << "UNREACHABLE";
452      break;
453  }
454  ++cur_reg_;
455}
456
457extern "C" uint64_t artQuickToInterpreterBridge(mirror::ArtMethod* method, Thread* self,
458                                                StackReference<mirror::ArtMethod>* sp)
459    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
460  // Ensure we don't get thread suspension until the object arguments are safely in the shadow
461  // frame.
462  FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsAndArgs);
463
464  if (method->IsAbstract()) {
465    ThrowAbstractMethodError(method);
466    return 0;
467  } else {
468    DCHECK(!method->IsNative()) << PrettyMethod(method);
469    const char* old_cause = self->StartAssertNoThreadSuspension(
470        "Building interpreter shadow frame");
471    const DexFile::CodeItem* code_item = method->GetCodeItem();
472    DCHECK(code_item != nullptr) << PrettyMethod(method);
473    uint16_t num_regs = code_item->registers_size_;
474    void* memory = alloca(ShadowFrame::ComputeSize(num_regs));
475    // No last shadow coming from quick.
476    ShadowFrame* shadow_frame(ShadowFrame::Create(num_regs, nullptr, method, 0, memory));
477    size_t first_arg_reg = code_item->registers_size_ - code_item->ins_size_;
478    uint32_t shorty_len = 0;
479    const char* shorty = method->GetShorty(&shorty_len);
480    BuildQuickShadowFrameVisitor shadow_frame_builder(sp, method->IsStatic(), shorty, shorty_len,
481                                                      shadow_frame, first_arg_reg);
482    shadow_frame_builder.VisitArguments();
483    // Push a transition back into managed code onto the linked list in thread.
484    ManagedStack fragment;
485    self->PushManagedStackFragment(&fragment);
486    self->PushShadowFrame(shadow_frame);
487    self->EndAssertNoThreadSuspension(old_cause);
488
489    if (method->IsStatic() && !method->GetDeclaringClass()->IsInitialized()) {
490      // Ensure static method's class is initialized.
491      StackHandleScope<1> hs(self);
492      Handle<mirror::Class> h_class(hs.NewHandle(method->GetDeclaringClass()));
493      if (!Runtime::Current()->GetClassLinker()->EnsureInitialized(h_class, true, true)) {
494        DCHECK(Thread::Current()->IsExceptionPending()) << PrettyMethod(method);
495        self->PopManagedStackFragment(fragment);
496        return 0;
497      }
498    }
499
500    StackHandleScope<1> hs(self);
501    MethodHelper mh(hs.NewHandle(method));
502    JValue result = interpreter::EnterInterpreterFromStub(self, mh, code_item, *shadow_frame);
503    // Pop transition.
504    self->PopManagedStackFragment(fragment);
505    // No need to restore the args since the method has already been run by the interpreter.
506    return result.GetJ();
507  }
508}
509
510// Visits arguments on the stack placing them into the args vector, Object* arguments are converted
511// to jobjects.
512class BuildQuickArgumentVisitor FINAL : public QuickArgumentVisitor {
513 public:
514  BuildQuickArgumentVisitor(StackReference<mirror::ArtMethod>* sp, bool is_static,
515                            const char* shorty, uint32_t shorty_len,
516                            ScopedObjectAccessUnchecked* soa, std::vector<jvalue>* args) :
517      QuickArgumentVisitor(sp, is_static, shorty, shorty_len), soa_(soa), args_(args) {}
518
519  void Visit() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) OVERRIDE;
520
521  void FixupReferences() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
522
523 private:
524  ScopedObjectAccessUnchecked* const soa_;
525  std::vector<jvalue>* const args_;
526  // References which we must update when exiting in case the GC moved the objects.
527  std::vector<std::pair<jobject, StackReference<mirror::Object>*>> references_;
528
529  DISALLOW_COPY_AND_ASSIGN(BuildQuickArgumentVisitor);
530};
531
532void BuildQuickArgumentVisitor::Visit() {
533  jvalue val;
534  Primitive::Type type = GetParamPrimitiveType();
535  switch (type) {
536    case Primitive::kPrimNot: {
537      StackReference<mirror::Object>* stack_ref =
538          reinterpret_cast<StackReference<mirror::Object>*>(GetParamAddress());
539      val.l = soa_->AddLocalReference<jobject>(stack_ref->AsMirrorPtr());
540      references_.push_back(std::make_pair(val.l, stack_ref));
541      break;
542    }
543    case Primitive::kPrimLong:  // Fall-through.
544    case Primitive::kPrimDouble:
545      if (IsSplitLongOrDouble()) {
546        val.j = ReadSplitLongParam();
547      } else {
548        val.j = *reinterpret_cast<jlong*>(GetParamAddress());
549      }
550      break;
551    case Primitive::kPrimBoolean:  // Fall-through.
552    case Primitive::kPrimByte:     // Fall-through.
553    case Primitive::kPrimChar:     // Fall-through.
554    case Primitive::kPrimShort:    // Fall-through.
555    case Primitive::kPrimInt:      // Fall-through.
556    case Primitive::kPrimFloat:
557      val.i = *reinterpret_cast<jint*>(GetParamAddress());
558      break;
559    case Primitive::kPrimVoid:
560      LOG(FATAL) << "UNREACHABLE";
561      val.j = 0;
562      break;
563  }
564  args_->push_back(val);
565}
566
567void BuildQuickArgumentVisitor::FixupReferences() {
568  // Fixup any references which may have changed.
569  for (const auto& pair : references_) {
570    pair.second->Assign(soa_->Decode<mirror::Object*>(pair.first));
571    soa_->Env()->DeleteLocalRef(pair.first);
572  }
573}
574
575// Handler for invocation on proxy methods. On entry a frame will exist for the proxy object method
576// which is responsible for recording callee save registers. We explicitly place into jobjects the
577// incoming reference arguments (so they survive GC). We invoke the invocation handler, which is a
578// field within the proxy object, which will box the primitive arguments and deal with error cases.
579extern "C" uint64_t artQuickProxyInvokeHandler(mirror::ArtMethod* proxy_method,
580                                               mirror::Object* receiver,
581                                               Thread* self, StackReference<mirror::ArtMethod>* sp)
582    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
583  DCHECK(proxy_method->IsProxyMethod()) << PrettyMethod(proxy_method);
584  DCHECK(receiver->GetClass()->IsProxyClass()) << PrettyMethod(proxy_method);
585  // Ensure we don't get thread suspension until the object arguments are safely in jobjects.
586  const char* old_cause =
587      self->StartAssertNoThreadSuspension("Adding to IRT proxy object arguments");
588  // Register the top of the managed stack, making stack crawlable.
589  DCHECK_EQ(sp->AsMirrorPtr(), proxy_method) << PrettyMethod(proxy_method);
590  self->SetTopOfStack(sp, 0);
591  DCHECK_EQ(proxy_method->GetFrameSizeInBytes(),
592            Runtime::Current()->GetCalleeSaveMethod(Runtime::kRefsAndArgs)->GetFrameSizeInBytes())
593      << PrettyMethod(proxy_method);
594  self->VerifyStack();
595  // Start new JNI local reference state.
596  JNIEnvExt* env = self->GetJniEnv();
597  ScopedObjectAccessUnchecked soa(env);
598  ScopedJniEnvLocalRefState env_state(env);
599  // Create local ref. copies of proxy method and the receiver.
600  jobject rcvr_jobj = soa.AddLocalReference<jobject>(receiver);
601
602  // Placing arguments into args vector and remove the receiver.
603  mirror::ArtMethod* non_proxy_method = proxy_method->GetInterfaceMethodIfProxy();
604  CHECK(!non_proxy_method->IsStatic()) << PrettyMethod(proxy_method) << " "
605                                       << PrettyMethod(non_proxy_method);
606  std::vector<jvalue> args;
607  uint32_t shorty_len = 0;
608  const char* shorty = proxy_method->GetShorty(&shorty_len);
609  BuildQuickArgumentVisitor local_ref_visitor(sp, false, shorty, shorty_len, &soa, &args);
610
611  local_ref_visitor.VisitArguments();
612  DCHECK_GT(args.size(), 0U) << PrettyMethod(proxy_method);
613  args.erase(args.begin());
614
615  // Convert proxy method into expected interface method.
616  mirror::ArtMethod* interface_method = proxy_method->FindOverriddenMethod();
617  DCHECK(interface_method != NULL) << PrettyMethod(proxy_method);
618  DCHECK(!interface_method->IsProxyMethod()) << PrettyMethod(interface_method);
619  jobject interface_method_jobj = soa.AddLocalReference<jobject>(interface_method);
620
621  // All naked Object*s should now be in jobjects, so its safe to go into the main invoke code
622  // that performs allocations.
623  self->EndAssertNoThreadSuspension(old_cause);
624  JValue result = InvokeProxyInvocationHandler(soa, shorty, rcvr_jobj, interface_method_jobj, args);
625  // Restore references which might have moved.
626  local_ref_visitor.FixupReferences();
627  return result.GetJ();
628}
629
630// Read object references held in arguments from quick frames and place in a JNI local references,
631// so they don't get garbage collected.
632class RememberForGcArgumentVisitor FINAL : public QuickArgumentVisitor {
633 public:
634  RememberForGcArgumentVisitor(StackReference<mirror::ArtMethod>* sp, bool is_static,
635                               const char* shorty, uint32_t shorty_len,
636                               ScopedObjectAccessUnchecked* soa) :
637      QuickArgumentVisitor(sp, is_static, shorty, shorty_len), soa_(soa) {}
638
639  void Visit() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) OVERRIDE;
640
641  void FixupReferences() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
642
643 private:
644  ScopedObjectAccessUnchecked* const soa_;
645  // References which we must update when exiting in case the GC moved the objects.
646  std::vector<std::pair<jobject, StackReference<mirror::Object>*> > references_;
647
648  DISALLOW_COPY_AND_ASSIGN(RememberForGcArgumentVisitor);
649};
650
651void RememberForGcArgumentVisitor::Visit() {
652  if (IsParamAReference()) {
653    StackReference<mirror::Object>* stack_ref =
654        reinterpret_cast<StackReference<mirror::Object>*>(GetParamAddress());
655    jobject reference =
656        soa_->AddLocalReference<jobject>(stack_ref->AsMirrorPtr());
657    references_.push_back(std::make_pair(reference, stack_ref));
658  }
659}
660
661void RememberForGcArgumentVisitor::FixupReferences() {
662  // Fixup any references which may have changed.
663  for (const auto& pair : references_) {
664    pair.second->Assign(soa_->Decode<mirror::Object*>(pair.first));
665    soa_->Env()->DeleteLocalRef(pair.first);
666  }
667}
668
669// Lazily resolve a method for quick. Called by stub code.
670extern "C" const void* artQuickResolutionTrampoline(mirror::ArtMethod* called,
671                                                    mirror::Object* receiver,
672                                                    Thread* self,
673                                                    StackReference<mirror::ArtMethod>* sp)
674    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
675  FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsAndArgs);
676  // Start new JNI local reference state
677  JNIEnvExt* env = self->GetJniEnv();
678  ScopedObjectAccessUnchecked soa(env);
679  ScopedJniEnvLocalRefState env_state(env);
680  const char* old_cause = self->StartAssertNoThreadSuspension("Quick method resolution set up");
681
682  // Compute details about the called method (avoid GCs)
683  ClassLinker* linker = Runtime::Current()->GetClassLinker();
684  mirror::ArtMethod* caller = QuickArgumentVisitor::GetCallingMethod(sp);
685  InvokeType invoke_type;
686  const DexFile* dex_file;
687  uint32_t dex_method_idx;
688  if (called->IsRuntimeMethod()) {
689    uint32_t dex_pc = caller->ToDexPc(QuickArgumentVisitor::GetCallingPc(sp));
690    const DexFile::CodeItem* code;
691    dex_file = caller->GetDexFile();
692    code = caller->GetCodeItem();
693    CHECK_LT(dex_pc, code->insns_size_in_code_units_);
694    const Instruction* instr = Instruction::At(&code->insns_[dex_pc]);
695    Instruction::Code instr_code = instr->Opcode();
696    bool is_range;
697    switch (instr_code) {
698      case Instruction::INVOKE_DIRECT:
699        invoke_type = kDirect;
700        is_range = false;
701        break;
702      case Instruction::INVOKE_DIRECT_RANGE:
703        invoke_type = kDirect;
704        is_range = true;
705        break;
706      case Instruction::INVOKE_STATIC:
707        invoke_type = kStatic;
708        is_range = false;
709        break;
710      case Instruction::INVOKE_STATIC_RANGE:
711        invoke_type = kStatic;
712        is_range = true;
713        break;
714      case Instruction::INVOKE_SUPER:
715        invoke_type = kSuper;
716        is_range = false;
717        break;
718      case Instruction::INVOKE_SUPER_RANGE:
719        invoke_type = kSuper;
720        is_range = true;
721        break;
722      case Instruction::INVOKE_VIRTUAL:
723        invoke_type = kVirtual;
724        is_range = false;
725        break;
726      case Instruction::INVOKE_VIRTUAL_RANGE:
727        invoke_type = kVirtual;
728        is_range = true;
729        break;
730      case Instruction::INVOKE_INTERFACE:
731        invoke_type = kInterface;
732        is_range = false;
733        break;
734      case Instruction::INVOKE_INTERFACE_RANGE:
735        invoke_type = kInterface;
736        is_range = true;
737        break;
738      default:
739        LOG(FATAL) << "Unexpected call into trampoline: " << instr->DumpString(NULL);
740        // Avoid used uninitialized warnings.
741        invoke_type = kDirect;
742        is_range = false;
743    }
744    dex_method_idx = (is_range) ? instr->VRegB_3rc() : instr->VRegB_35c();
745  } else {
746    invoke_type = kStatic;
747    dex_file = called->GetDexFile();
748    dex_method_idx = called->GetDexMethodIndex();
749  }
750  uint32_t shorty_len;
751  const char* shorty =
752      dex_file->GetMethodShorty(dex_file->GetMethodId(dex_method_idx), &shorty_len);
753  RememberForGcArgumentVisitor visitor(sp, invoke_type == kStatic, shorty, shorty_len, &soa);
754  visitor.VisitArguments();
755  self->EndAssertNoThreadSuspension(old_cause);
756  bool virtual_or_interface = invoke_type == kVirtual || invoke_type == kInterface;
757  // Resolve method filling in dex cache.
758  if (UNLIKELY(called->IsRuntimeMethod())) {
759    StackHandleScope<1> hs(self);
760    mirror::Object* dummy = nullptr;
761    HandleWrapper<mirror::Object> h_receiver(
762        hs.NewHandleWrapper(virtual_or_interface ? &receiver : &dummy));
763    called = linker->ResolveMethod(self, dex_method_idx, &caller, invoke_type);
764  }
765  const void* code = NULL;
766  if (LIKELY(!self->IsExceptionPending())) {
767    // Incompatible class change should have been handled in resolve method.
768    CHECK(!called->CheckIncompatibleClassChange(invoke_type))
769        << PrettyMethod(called) << " " << invoke_type;
770    if (virtual_or_interface) {
771      // Refine called method based on receiver.
772      CHECK(receiver != nullptr) << invoke_type;
773
774      mirror::ArtMethod* orig_called = called;
775      if (invoke_type == kVirtual) {
776        called = receiver->GetClass()->FindVirtualMethodForVirtual(called);
777      } else {
778        called = receiver->GetClass()->FindVirtualMethodForInterface(called);
779      }
780
781      CHECK(called != nullptr) << PrettyMethod(orig_called) << " "
782                               << PrettyTypeOf(receiver) << " "
783                               << invoke_type << " " << orig_called->GetVtableIndex();
784
785      // We came here because of sharpening. Ensure the dex cache is up-to-date on the method index
786      // of the sharpened method.
787      if (called->GetDexCacheResolvedMethods() == caller->GetDexCacheResolvedMethods()) {
788        caller->GetDexCacheResolvedMethods()->Set<false>(called->GetDexMethodIndex(), called);
789      } else {
790        // Calling from one dex file to another, need to compute the method index appropriate to
791        // the caller's dex file. Since we get here only if the original called was a runtime
792        // method, we've got the correct dex_file and a dex_method_idx from above.
793        DCHECK_EQ(caller->GetDexFile(), dex_file);
794        StackHandleScope<1> hs(self);
795        MethodHelper mh(hs.NewHandle(called));
796        uint32_t method_index = mh.FindDexMethodIndexInOtherDexFile(*dex_file, dex_method_idx);
797        if (method_index != DexFile::kDexNoIndex) {
798          caller->GetDexCacheResolvedMethods()->Set<false>(method_index, called);
799        }
800      }
801    }
802    // Ensure that the called method's class is initialized.
803    StackHandleScope<1> hs(soa.Self());
804    Handle<mirror::Class> called_class(hs.NewHandle(called->GetDeclaringClass()));
805    linker->EnsureInitialized(called_class, true, true);
806    if (LIKELY(called_class->IsInitialized())) {
807      code = called->GetEntryPointFromQuickCompiledCode();
808    } else if (called_class->IsInitializing()) {
809      if (invoke_type == kStatic) {
810        // Class is still initializing, go to oat and grab code (trampoline must be left in place
811        // until class is initialized to stop races between threads).
812        code = linker->GetQuickOatCodeFor(called);
813      } else {
814        // No trampoline for non-static methods.
815        code = called->GetEntryPointFromQuickCompiledCode();
816      }
817    } else {
818      DCHECK(called_class->IsErroneous());
819    }
820  }
821  CHECK_EQ(code == NULL, self->IsExceptionPending());
822  // Fixup any locally saved objects may have moved during a GC.
823  visitor.FixupReferences();
824  // Place called method in callee-save frame to be placed as first argument to quick method.
825  sp->Assign(called);
826  return code;
827}
828
829/*
830 * This class uses a couple of observations to unite the different calling conventions through
831 * a few constants.
832 *
833 * 1) Number of registers used for passing is normally even, so counting down has no penalty for
834 *    possible alignment.
835 * 2) Known 64b architectures store 8B units on the stack, both for integral and floating point
836 *    types, so using uintptr_t is OK. Also means that we can use kRegistersNeededX to denote
837 *    when we have to split things
838 * 3) The only soft-float, Arm, is 32b, so no widening needs to be taken into account for floats
839 *    and we can use Int handling directly.
840 * 4) Only 64b architectures widen, and their stack is aligned 8B anyways, so no padding code
841 *    necessary when widening. Also, widening of Ints will take place implicitly, and the
842 *    extension should be compatible with Aarch64, which mandates copying the available bits
843 *    into LSB and leaving the rest unspecified.
844 * 5) Aligning longs and doubles is necessary on arm only, and it's the same in registers and on
845 *    the stack.
846 * 6) There is only little endian.
847 *
848 *
849 * Actual work is supposed to be done in a delegate of the template type. The interface is as
850 * follows:
851 *
852 * void PushGpr(uintptr_t):   Add a value for the next GPR
853 *
854 * void PushFpr4(float):      Add a value for the next FPR of size 32b. Is only called if we need
855 *                            padding, that is, think the architecture is 32b and aligns 64b.
856 *
857 * void PushFpr8(uint64_t):   Push a double. We _will_ call this on 32b, it's the callee's job to
858 *                            split this if necessary. The current state will have aligned, if
859 *                            necessary.
860 *
861 * void PushStack(uintptr_t): Push a value to the stack.
862 *
863 * uintptr_t PushHandleScope(mirror::Object* ref): Add a reference to the HandleScope. This _will_ have nullptr,
864 *                                          as this might be important for null initialization.
865 *                                          Must return the jobject, that is, the reference to the
866 *                                          entry in the HandleScope (nullptr if necessary).
867 *
868 */
869template<class T> class BuildNativeCallFrameStateMachine {
870 public:
871#if defined(__arm__)
872  // TODO: These are all dummy values!
873  static constexpr bool kNativeSoftFloatAbi = true;
874  static constexpr size_t kNumNativeGprArgs = 4;  // 4 arguments passed in GPRs, r0-r3
875  static constexpr size_t kNumNativeFprArgs = 0;  // 0 arguments passed in FPRs.
876
877  static constexpr size_t kRegistersNeededForLong = 2;
878  static constexpr size_t kRegistersNeededForDouble = 2;
879  static constexpr bool kMultiRegistersAligned = true;
880  static constexpr bool kMultiRegistersWidened = false;
881  static constexpr bool kAlignLongOnStack = true;
882  static constexpr bool kAlignDoubleOnStack = true;
883#elif defined(__aarch64__)
884  static constexpr bool kNativeSoftFloatAbi = false;  // This is a hard float ABI.
885  static constexpr size_t kNumNativeGprArgs = 8;  // 6 arguments passed in GPRs.
886  static constexpr size_t kNumNativeFprArgs = 8;  // 8 arguments passed in FPRs.
887
888  static constexpr size_t kRegistersNeededForLong = 1;
889  static constexpr size_t kRegistersNeededForDouble = 1;
890  static constexpr bool kMultiRegistersAligned = false;
891  static constexpr bool kMultiRegistersWidened = false;
892  static constexpr bool kAlignLongOnStack = false;
893  static constexpr bool kAlignDoubleOnStack = false;
894#elif defined(__mips__)
895  // TODO: These are all dummy values!
896  static constexpr bool kNativeSoftFloatAbi = true;  // This is a hard float ABI.
897  static constexpr size_t kNumNativeGprArgs = 0;  // 6 arguments passed in GPRs.
898  static constexpr size_t kNumNativeFprArgs = 0;  // 8 arguments passed in FPRs.
899
900  static constexpr size_t kRegistersNeededForLong = 2;
901  static constexpr size_t kRegistersNeededForDouble = 2;
902  static constexpr bool kMultiRegistersAligned = true;
903  static constexpr bool kMultiRegistersWidened = true;
904  static constexpr bool kAlignLongOnStack = false;
905  static constexpr bool kAlignDoubleOnStack = false;
906#elif defined(__i386__)
907  // TODO: Check these!
908  static constexpr bool kNativeSoftFloatAbi = false;  // Not using int registers for fp
909  static constexpr size_t kNumNativeGprArgs = 0;  // 6 arguments passed in GPRs.
910  static constexpr size_t kNumNativeFprArgs = 0;  // 8 arguments passed in FPRs.
911
912  static constexpr size_t kRegistersNeededForLong = 2;
913  static constexpr size_t kRegistersNeededForDouble = 2;
914  static constexpr bool kMultiRegistersAligned = false;  // x86 not using regs, anyways
915  static constexpr bool kMultiRegistersWidened = false;
916  static constexpr bool kAlignLongOnStack = false;
917  static constexpr bool kAlignDoubleOnStack = false;
918#elif defined(__x86_64__)
919  static constexpr bool kNativeSoftFloatAbi = false;  // This is a hard float ABI.
920  static constexpr size_t kNumNativeGprArgs = 6;  // 6 arguments passed in GPRs.
921  static constexpr size_t kNumNativeFprArgs = 8;  // 8 arguments passed in FPRs.
922
923  static constexpr size_t kRegistersNeededForLong = 1;
924  static constexpr size_t kRegistersNeededForDouble = 1;
925  static constexpr bool kMultiRegistersAligned = false;
926  static constexpr bool kMultiRegistersWidened = false;
927  static constexpr bool kAlignLongOnStack = false;
928  static constexpr bool kAlignDoubleOnStack = false;
929#else
930#error "Unsupported architecture"
931#endif
932
933 public:
934  explicit BuildNativeCallFrameStateMachine(T* delegate)
935      : gpr_index_(kNumNativeGprArgs),
936        fpr_index_(kNumNativeFprArgs),
937        stack_entries_(0),
938        delegate_(delegate) {
939    // For register alignment, we want to assume that counters (gpr_index_, fpr_index_) are even iff
940    // the next register is even; counting down is just to make the compiler happy...
941    CHECK_EQ(kNumNativeGprArgs % 2, 0U);
942    CHECK_EQ(kNumNativeFprArgs % 2, 0U);
943  }
944
945  virtual ~BuildNativeCallFrameStateMachine() {}
946
947  bool HavePointerGpr() {
948    return gpr_index_ > 0;
949  }
950
951  void AdvancePointer(const void* val) {
952    if (HavePointerGpr()) {
953      gpr_index_--;
954      PushGpr(reinterpret_cast<uintptr_t>(val));
955    } else {
956      stack_entries_++;  // TODO: have a field for pointer length as multiple of 32b
957      PushStack(reinterpret_cast<uintptr_t>(val));
958      gpr_index_ = 0;
959    }
960  }
961
962  bool HaveHandleScopeGpr() {
963    return gpr_index_ > 0;
964  }
965
966  void AdvanceHandleScope(mirror::Object* ptr) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
967    uintptr_t handle = PushHandle(ptr);
968    if (HaveHandleScopeGpr()) {
969      gpr_index_--;
970      PushGpr(handle);
971    } else {
972      stack_entries_++;
973      PushStack(handle);
974      gpr_index_ = 0;
975    }
976  }
977
978  bool HaveIntGpr() {
979    return gpr_index_ > 0;
980  }
981
982  void AdvanceInt(uint32_t val) {
983    if (HaveIntGpr()) {
984      gpr_index_--;
985      PushGpr(val);
986    } else {
987      stack_entries_++;
988      PushStack(val);
989      gpr_index_ = 0;
990    }
991  }
992
993  bool HaveLongGpr() {
994    return gpr_index_ >= kRegistersNeededForLong + (LongGprNeedsPadding() ? 1 : 0);
995  }
996
997  bool LongGprNeedsPadding() {
998    return kRegistersNeededForLong > 1 &&     // only pad when using multiple registers
999        kAlignLongOnStack &&                  // and when it needs alignment
1000        (gpr_index_ & 1) == 1;                // counter is odd, see constructor
1001  }
1002
1003  bool LongStackNeedsPadding() {
1004    return kRegistersNeededForLong > 1 &&     // only pad when using multiple registers
1005        kAlignLongOnStack &&                  // and when it needs 8B alignment
1006        (stack_entries_ & 1) == 1;            // counter is odd
1007  }
1008
1009  void AdvanceLong(uint64_t val) {
1010    if (HaveLongGpr()) {
1011      if (LongGprNeedsPadding()) {
1012        PushGpr(0);
1013        gpr_index_--;
1014      }
1015      if (kRegistersNeededForLong == 1) {
1016        PushGpr(static_cast<uintptr_t>(val));
1017      } else {
1018        PushGpr(static_cast<uintptr_t>(val & 0xFFFFFFFF));
1019        PushGpr(static_cast<uintptr_t>((val >> 32) & 0xFFFFFFFF));
1020      }
1021      gpr_index_ -= kRegistersNeededForLong;
1022    } else {
1023      if (LongStackNeedsPadding()) {
1024        PushStack(0);
1025        stack_entries_++;
1026      }
1027      if (kRegistersNeededForLong == 1) {
1028        PushStack(static_cast<uintptr_t>(val));
1029        stack_entries_++;
1030      } else {
1031        PushStack(static_cast<uintptr_t>(val & 0xFFFFFFFF));
1032        PushStack(static_cast<uintptr_t>((val >> 32) & 0xFFFFFFFF));
1033        stack_entries_ += 2;
1034      }
1035      gpr_index_ = 0;
1036    }
1037  }
1038
1039  bool HaveFloatFpr() {
1040    return fpr_index_ > 0;
1041  }
1042
1043  void AdvanceFloat(float val) {
1044    if (kNativeSoftFloatAbi) {
1045      AdvanceInt(bit_cast<float, uint32_t>(val));
1046    } else {
1047      if (HaveFloatFpr()) {
1048        fpr_index_--;
1049        if (kRegistersNeededForDouble == 1) {
1050          if (kMultiRegistersWidened) {
1051            PushFpr8(bit_cast<double, uint64_t>(val));
1052          } else {
1053            // No widening, just use the bits.
1054            PushFpr8(bit_cast<float, uint64_t>(val));
1055          }
1056        } else {
1057          PushFpr4(val);
1058        }
1059      } else {
1060        stack_entries_++;
1061        if (kRegistersNeededForDouble == 1 && kMultiRegistersWidened) {
1062          // Need to widen before storing: Note the "double" in the template instantiation.
1063          // Note: We need to jump through those hoops to make the compiler happy.
1064          DCHECK_EQ(sizeof(uintptr_t), sizeof(uint64_t));
1065          PushStack(static_cast<uintptr_t>(bit_cast<double, uint64_t>(val)));
1066        } else {
1067          PushStack(bit_cast<float, uintptr_t>(val));
1068        }
1069        fpr_index_ = 0;
1070      }
1071    }
1072  }
1073
1074  bool HaveDoubleFpr() {
1075    return fpr_index_ >= kRegistersNeededForDouble + (DoubleFprNeedsPadding() ? 1 : 0);
1076  }
1077
1078  bool DoubleFprNeedsPadding() {
1079    return kRegistersNeededForDouble > 1 &&     // only pad when using multiple registers
1080        kAlignDoubleOnStack &&                  // and when it needs alignment
1081        (fpr_index_ & 1) == 1;                  // counter is odd, see constructor
1082  }
1083
1084  bool DoubleStackNeedsPadding() {
1085    return kRegistersNeededForDouble > 1 &&     // only pad when using multiple registers
1086        kAlignDoubleOnStack &&                  // and when it needs 8B alignment
1087        (stack_entries_ & 1) == 1;              // counter is odd
1088  }
1089
1090  void AdvanceDouble(uint64_t val) {
1091    if (kNativeSoftFloatAbi) {
1092      AdvanceLong(val);
1093    } else {
1094      if (HaveDoubleFpr()) {
1095        if (DoubleFprNeedsPadding()) {
1096          PushFpr4(0);
1097          fpr_index_--;
1098        }
1099        PushFpr8(val);
1100        fpr_index_ -= kRegistersNeededForDouble;
1101      } else {
1102        if (DoubleStackNeedsPadding()) {
1103          PushStack(0);
1104          stack_entries_++;
1105        }
1106        if (kRegistersNeededForDouble == 1) {
1107          PushStack(static_cast<uintptr_t>(val));
1108          stack_entries_++;
1109        } else {
1110          PushStack(static_cast<uintptr_t>(val & 0xFFFFFFFF));
1111          PushStack(static_cast<uintptr_t>((val >> 32) & 0xFFFFFFFF));
1112          stack_entries_ += 2;
1113        }
1114        fpr_index_ = 0;
1115      }
1116    }
1117  }
1118
1119  uint32_t getStackEntries() {
1120    return stack_entries_;
1121  }
1122
1123  uint32_t getNumberOfUsedGprs() {
1124    return kNumNativeGprArgs - gpr_index_;
1125  }
1126
1127  uint32_t getNumberOfUsedFprs() {
1128    return kNumNativeFprArgs - fpr_index_;
1129  }
1130
1131 private:
1132  void PushGpr(uintptr_t val) {
1133    delegate_->PushGpr(val);
1134  }
1135  void PushFpr4(float val) {
1136    delegate_->PushFpr4(val);
1137  }
1138  void PushFpr8(uint64_t val) {
1139    delegate_->PushFpr8(val);
1140  }
1141  void PushStack(uintptr_t val) {
1142    delegate_->PushStack(val);
1143  }
1144  uintptr_t PushHandle(mirror::Object* ref) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1145    return delegate_->PushHandle(ref);
1146  }
1147
1148  uint32_t gpr_index_;      // Number of free GPRs
1149  uint32_t fpr_index_;      // Number of free FPRs
1150  uint32_t stack_entries_;  // Stack entries are in multiples of 32b, as floats are usually not
1151                            // extended
1152  T* delegate_;             // What Push implementation gets called
1153};
1154
1155// Computes the sizes of register stacks and call stack area. Handling of references can be extended
1156// in subclasses.
1157//
1158// To handle native pointers, use "L" in the shorty for an object reference, which simulates
1159// them with handles.
1160class ComputeNativeCallFrameSize {
1161 public:
1162  ComputeNativeCallFrameSize() : num_stack_entries_(0) {}
1163
1164  virtual ~ComputeNativeCallFrameSize() {}
1165
1166  uint32_t GetStackSize() {
1167    return num_stack_entries_ * sizeof(uintptr_t);
1168  }
1169
1170  uint8_t* LayoutCallStack(uint8_t* sp8) {
1171    sp8 -= GetStackSize();
1172    // Align by kStackAlignment.
1173    sp8 = reinterpret_cast<uint8_t*>(RoundDown(reinterpret_cast<uintptr_t>(sp8), kStackAlignment));
1174    return sp8;
1175  }
1176
1177  uint8_t* LayoutCallRegisterStacks(uint8_t* sp8, uintptr_t** start_gpr, uint32_t** start_fpr) {
1178    // Assumption is OK right now, as we have soft-float arm
1179    size_t fregs = BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize>::kNumNativeFprArgs;
1180    sp8 -= fregs * sizeof(uintptr_t);
1181    *start_fpr = reinterpret_cast<uint32_t*>(sp8);
1182    size_t iregs = BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize>::kNumNativeGprArgs;
1183    sp8 -= iregs * sizeof(uintptr_t);
1184    *start_gpr = reinterpret_cast<uintptr_t*>(sp8);
1185    return sp8;
1186  }
1187
1188  uint8_t* LayoutNativeCall(uint8_t* sp8, uintptr_t** start_stack, uintptr_t** start_gpr,
1189                            uint32_t** start_fpr) {
1190    // Native call stack.
1191    sp8 = LayoutCallStack(sp8);
1192    *start_stack = reinterpret_cast<uintptr_t*>(sp8);
1193
1194    // Put fprs and gprs below.
1195    sp8 = LayoutCallRegisterStacks(sp8, start_gpr, start_fpr);
1196
1197    // Return the new bottom.
1198    return sp8;
1199  }
1200
1201  virtual void WalkHeader(BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize>* sm)
1202      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {}
1203
1204  void Walk(const char* shorty, uint32_t shorty_len) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1205    BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize> sm(this);
1206
1207    WalkHeader(&sm);
1208
1209    for (uint32_t i = 1; i < shorty_len; ++i) {
1210      Primitive::Type cur_type_ = Primitive::GetType(shorty[i]);
1211      switch (cur_type_) {
1212        case Primitive::kPrimNot:
1213          sm.AdvanceHandleScope(
1214              reinterpret_cast<mirror::Object*>(0x12345678));
1215          break;
1216
1217        case Primitive::kPrimBoolean:
1218        case Primitive::kPrimByte:
1219        case Primitive::kPrimChar:
1220        case Primitive::kPrimShort:
1221        case Primitive::kPrimInt:
1222          sm.AdvanceInt(0);
1223          break;
1224        case Primitive::kPrimFloat:
1225          sm.AdvanceFloat(0);
1226          break;
1227        case Primitive::kPrimDouble:
1228          sm.AdvanceDouble(0);
1229          break;
1230        case Primitive::kPrimLong:
1231          sm.AdvanceLong(0);
1232          break;
1233        default:
1234          LOG(FATAL) << "Unexpected type: " << cur_type_ << " in " << shorty;
1235      }
1236    }
1237
1238    num_stack_entries_ = sm.getStackEntries();
1239  }
1240
1241  void PushGpr(uintptr_t /* val */) {
1242    // not optimizing registers, yet
1243  }
1244
1245  void PushFpr4(float /* val */) {
1246    // not optimizing registers, yet
1247  }
1248
1249  void PushFpr8(uint64_t /* val */) {
1250    // not optimizing registers, yet
1251  }
1252
1253  void PushStack(uintptr_t /* val */) {
1254    // counting is already done in the superclass
1255  }
1256
1257  virtual uintptr_t PushHandle(mirror::Object* /* ptr */) {
1258    return reinterpret_cast<uintptr_t>(nullptr);
1259  }
1260
1261 protected:
1262  uint32_t num_stack_entries_;
1263};
1264
1265class ComputeGenericJniFrameSize FINAL : public ComputeNativeCallFrameSize {
1266 public:
1267  ComputeGenericJniFrameSize() : num_handle_scope_references_(0) {}
1268
1269  // Lays out the callee-save frame. Assumes that the incorrect frame corresponding to RefsAndArgs
1270  // is at *m = sp. Will update to point to the bottom of the save frame.
1271  //
1272  // Note: assumes ComputeAll() has been run before.
1273  void LayoutCalleeSaveFrame(StackReference<mirror::ArtMethod>** m, void* sp, HandleScope** table,
1274                             uint32_t* handle_scope_entries)
1275      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1276    mirror::ArtMethod* method = (*m)->AsMirrorPtr();
1277
1278    uint8_t* sp8 = reinterpret_cast<uint8_t*>(sp);
1279
1280    // First, fix up the layout of the callee-save frame.
1281    // We have to squeeze in the HandleScope, and relocate the method pointer.
1282
1283    // "Free" the slot for the method.
1284    sp8 += kPointerSize;  // In the callee-save frame we use a full pointer.
1285
1286    // Under the callee saves put handle scope and new method stack reference.
1287    *handle_scope_entries = num_handle_scope_references_;
1288
1289    size_t handle_scope_size = HandleScope::SizeOf(num_handle_scope_references_);
1290    size_t scope_and_method = handle_scope_size + sizeof(StackReference<mirror::ArtMethod>);
1291
1292    sp8 -= scope_and_method;
1293    // Align by kStackAlignment.
1294    sp8 = reinterpret_cast<uint8_t*>(RoundDown(
1295        reinterpret_cast<uintptr_t>(sp8), kStackAlignment));
1296
1297    uint8_t* sp8_table = sp8 + sizeof(StackReference<mirror::ArtMethod>);
1298    *table = reinterpret_cast<HandleScope*>(sp8_table);
1299    (*table)->SetNumberOfReferences(num_handle_scope_references_);
1300
1301    // Add a slot for the method pointer, and fill it. Fix the pointer-pointer given to us.
1302    uint8_t* method_pointer = sp8;
1303    StackReference<mirror::ArtMethod>* new_method_ref =
1304        reinterpret_cast<StackReference<mirror::ArtMethod>*>(method_pointer);
1305    new_method_ref->Assign(method);
1306    *m = new_method_ref;
1307  }
1308
1309  // Adds space for the cookie. Note: may leave stack unaligned.
1310  void LayoutCookie(uint8_t** sp) {
1311    // Reference cookie and padding
1312    *sp -= 8;
1313  }
1314
1315  // Re-layout the callee-save frame (insert a handle-scope). Then add space for the cookie.
1316  // Returns the new bottom. Note: this may be unaligned.
1317  uint8_t* LayoutJNISaveFrame(StackReference<mirror::ArtMethod>** m, void* sp, HandleScope** table,
1318                              uint32_t* handle_scope_entries)
1319      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1320    // First, fix up the layout of the callee-save frame.
1321    // We have to squeeze in the HandleScope, and relocate the method pointer.
1322    LayoutCalleeSaveFrame(m, sp, table, handle_scope_entries);
1323
1324    // The bottom of the callee-save frame is now where the method is, *m.
1325    uint8_t* sp8 = reinterpret_cast<uint8_t*>(*m);
1326
1327    // Add space for cookie.
1328    LayoutCookie(&sp8);
1329
1330    return sp8;
1331  }
1332
1333  // WARNING: After this, *sp won't be pointing to the method anymore!
1334  uint8_t* ComputeLayout(StackReference<mirror::ArtMethod>** m, bool is_static, const char* shorty,
1335                         uint32_t shorty_len, HandleScope** table, uint32_t* handle_scope_entries,
1336                         uintptr_t** start_stack, uintptr_t** start_gpr, uint32_t** start_fpr)
1337      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1338    Walk(shorty, shorty_len);
1339
1340    // JNI part.
1341    uint8_t* sp8 = LayoutJNISaveFrame(m, reinterpret_cast<void*>(*m), table, handle_scope_entries);
1342
1343    sp8 = LayoutNativeCall(sp8, start_stack, start_gpr, start_fpr);
1344
1345    // Return the new bottom.
1346    return sp8;
1347  }
1348
1349  uintptr_t PushHandle(mirror::Object* /* ptr */) OVERRIDE;
1350
1351  // Add JNIEnv* and jobj/jclass before the shorty-derived elements.
1352  void WalkHeader(BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize>* sm) OVERRIDE
1353      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
1354
1355 private:
1356  uint32_t num_handle_scope_references_;
1357};
1358
1359uintptr_t ComputeGenericJniFrameSize::PushHandle(mirror::Object* /* ptr */) {
1360  num_handle_scope_references_++;
1361  return reinterpret_cast<uintptr_t>(nullptr);
1362}
1363
1364void ComputeGenericJniFrameSize::WalkHeader(
1365    BuildNativeCallFrameStateMachine<ComputeNativeCallFrameSize>* sm) {
1366  // JNIEnv
1367  sm->AdvancePointer(nullptr);
1368
1369  // Class object or this as first argument
1370  sm->AdvanceHandleScope(reinterpret_cast<mirror::Object*>(0x12345678));
1371}
1372
1373// Class to push values to three separate regions. Used to fill the native call part. Adheres to
1374// the template requirements of BuildGenericJniFrameStateMachine.
1375class FillNativeCall {
1376 public:
1377  FillNativeCall(uintptr_t* gpr_regs, uint32_t* fpr_regs, uintptr_t* stack_args) :
1378      cur_gpr_reg_(gpr_regs), cur_fpr_reg_(fpr_regs), cur_stack_arg_(stack_args) {}
1379
1380  virtual ~FillNativeCall() {}
1381
1382  void Reset(uintptr_t* gpr_regs, uint32_t* fpr_regs, uintptr_t* stack_args) {
1383    cur_gpr_reg_ = gpr_regs;
1384    cur_fpr_reg_ = fpr_regs;
1385    cur_stack_arg_ = stack_args;
1386  }
1387
1388  void PushGpr(uintptr_t val) {
1389    *cur_gpr_reg_ = val;
1390    cur_gpr_reg_++;
1391  }
1392
1393  void PushFpr4(float val) {
1394    *cur_fpr_reg_ = val;
1395    cur_fpr_reg_++;
1396  }
1397
1398  void PushFpr8(uint64_t val) {
1399    uint64_t* tmp = reinterpret_cast<uint64_t*>(cur_fpr_reg_);
1400    *tmp = val;
1401    cur_fpr_reg_ += 2;
1402  }
1403
1404  void PushStack(uintptr_t val) {
1405    *cur_stack_arg_ = val;
1406    cur_stack_arg_++;
1407  }
1408
1409  virtual uintptr_t PushHandle(mirror::Object* ref) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1410    LOG(FATAL) << "(Non-JNI) Native call does not use handles.";
1411    return 0U;
1412  }
1413
1414 private:
1415  uintptr_t* cur_gpr_reg_;
1416  uint32_t* cur_fpr_reg_;
1417  uintptr_t* cur_stack_arg_;
1418};
1419
1420// Visits arguments on the stack placing them into a region lower down the stack for the benefit
1421// of transitioning into native code.
1422class BuildGenericJniFrameVisitor FINAL : public QuickArgumentVisitor {
1423 public:
1424  BuildGenericJniFrameVisitor(StackReference<mirror::ArtMethod>** sp, bool is_static,
1425                              const char* shorty, uint32_t shorty_len, Thread* self)
1426     : QuickArgumentVisitor(*sp, is_static, shorty, shorty_len),
1427       jni_call_(nullptr, nullptr, nullptr, nullptr), sm_(&jni_call_) {
1428    ComputeGenericJniFrameSize fsc;
1429    uintptr_t* start_gpr_reg;
1430    uint32_t* start_fpr_reg;
1431    uintptr_t* start_stack_arg;
1432    uint32_t handle_scope_entries;
1433    bottom_of_used_area_ = fsc.ComputeLayout(sp, is_static, shorty, shorty_len, &handle_scope_,
1434                                             &handle_scope_entries, &start_stack_arg,
1435                                             &start_gpr_reg, &start_fpr_reg);
1436
1437    handle_scope_->SetNumberOfReferences(handle_scope_entries);
1438    jni_call_.Reset(start_gpr_reg, start_fpr_reg, start_stack_arg, handle_scope_);
1439
1440    // jni environment is always first argument
1441    sm_.AdvancePointer(self->GetJniEnv());
1442
1443    if (is_static) {
1444      sm_.AdvanceHandleScope((*sp)->AsMirrorPtr()->GetDeclaringClass());
1445    }
1446  }
1447
1448  void Visit() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) OVERRIDE;
1449
1450  void FinalizeHandleScope(Thread* self) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
1451
1452  StackReference<mirror::Object>* GetFirstHandleScopeEntry()
1453      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1454    return handle_scope_->GetHandle(0).GetReference();
1455  }
1456
1457  jobject GetFirstHandleScopeJObject() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1458    return handle_scope_->GetHandle(0).ToJObject();
1459  }
1460
1461  void* GetBottomOfUsedArea() {
1462    return bottom_of_used_area_;
1463  }
1464
1465 private:
1466  // A class to fill a JNI call. Adds reference/handle-scope management to FillNativeCall.
1467  class FillJniCall FINAL : public FillNativeCall {
1468   public:
1469    FillJniCall(uintptr_t* gpr_regs, uint32_t* fpr_regs, uintptr_t* stack_args,
1470                HandleScope* handle_scope) : FillNativeCall(gpr_regs, fpr_regs, stack_args),
1471                                             handle_scope_(handle_scope), cur_entry_(0) {}
1472
1473    uintptr_t PushHandle(mirror::Object* ref) OVERRIDE SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
1474
1475    void Reset(uintptr_t* gpr_regs, uint32_t* fpr_regs, uintptr_t* stack_args, HandleScope* scope) {
1476      FillNativeCall::Reset(gpr_regs, fpr_regs, stack_args);
1477      handle_scope_ = scope;
1478      cur_entry_ = 0U;
1479    }
1480
1481    void ResetRemainingScopeSlots() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1482      // Initialize padding entries.
1483      size_t expected_slots = handle_scope_->NumberOfReferences();
1484      while (cur_entry_ < expected_slots) {
1485        handle_scope_->GetHandle(cur_entry_++).Assign(nullptr);
1486      }
1487      DCHECK_NE(cur_entry_, 0U);
1488    }
1489
1490   private:
1491    HandleScope* handle_scope_;
1492    size_t cur_entry_;
1493  };
1494
1495  HandleScope* handle_scope_;
1496  FillJniCall jni_call_;
1497  void* bottom_of_used_area_;
1498
1499  BuildNativeCallFrameStateMachine<FillJniCall> sm_;
1500
1501  DISALLOW_COPY_AND_ASSIGN(BuildGenericJniFrameVisitor);
1502};
1503
1504uintptr_t BuildGenericJniFrameVisitor::FillJniCall::PushHandle(mirror::Object* ref) {
1505  uintptr_t tmp;
1506  Handle<mirror::Object> h = handle_scope_->GetHandle(cur_entry_);
1507  h.Assign(ref);
1508  tmp = reinterpret_cast<uintptr_t>(h.ToJObject());
1509  cur_entry_++;
1510  return tmp;
1511}
1512
1513void BuildGenericJniFrameVisitor::Visit() {
1514  Primitive::Type type = GetParamPrimitiveType();
1515  switch (type) {
1516    case Primitive::kPrimLong: {
1517      jlong long_arg;
1518      if (IsSplitLongOrDouble()) {
1519        long_arg = ReadSplitLongParam();
1520      } else {
1521        long_arg = *reinterpret_cast<jlong*>(GetParamAddress());
1522      }
1523      sm_.AdvanceLong(long_arg);
1524      break;
1525    }
1526    case Primitive::kPrimDouble: {
1527      uint64_t double_arg;
1528      if (IsSplitLongOrDouble()) {
1529        // Read into union so that we don't case to a double.
1530        double_arg = ReadSplitLongParam();
1531      } else {
1532        double_arg = *reinterpret_cast<uint64_t*>(GetParamAddress());
1533      }
1534      sm_.AdvanceDouble(double_arg);
1535      break;
1536    }
1537    case Primitive::kPrimNot: {
1538      StackReference<mirror::Object>* stack_ref =
1539          reinterpret_cast<StackReference<mirror::Object>*>(GetParamAddress());
1540      sm_.AdvanceHandleScope(stack_ref->AsMirrorPtr());
1541      break;
1542    }
1543    case Primitive::kPrimFloat:
1544      sm_.AdvanceFloat(*reinterpret_cast<float*>(GetParamAddress()));
1545      break;
1546    case Primitive::kPrimBoolean:  // Fall-through.
1547    case Primitive::kPrimByte:     // Fall-through.
1548    case Primitive::kPrimChar:     // Fall-through.
1549    case Primitive::kPrimShort:    // Fall-through.
1550    case Primitive::kPrimInt:      // Fall-through.
1551      sm_.AdvanceInt(*reinterpret_cast<jint*>(GetParamAddress()));
1552      break;
1553    case Primitive::kPrimVoid:
1554      LOG(FATAL) << "UNREACHABLE";
1555      break;
1556  }
1557}
1558
1559void BuildGenericJniFrameVisitor::FinalizeHandleScope(Thread* self) {
1560  // Clear out rest of the scope.
1561  jni_call_.ResetRemainingScopeSlots();
1562  // Install HandleScope.
1563  self->PushHandleScope(handle_scope_);
1564}
1565
1566#if defined(__arm__) || defined(__aarch64__)
1567extern "C" void* artFindNativeMethod();
1568#else
1569extern "C" void* artFindNativeMethod(Thread* self);
1570#endif
1571
1572uint64_t artQuickGenericJniEndJNIRef(Thread* self, uint32_t cookie, jobject l, jobject lock) {
1573  if (lock != nullptr) {
1574    return reinterpret_cast<uint64_t>(JniMethodEndWithReferenceSynchronized(l, cookie, lock, self));
1575  } else {
1576    return reinterpret_cast<uint64_t>(JniMethodEndWithReference(l, cookie, self));
1577  }
1578}
1579
1580void artQuickGenericJniEndJNINonRef(Thread* self, uint32_t cookie, jobject lock) {
1581  if (lock != nullptr) {
1582    JniMethodEndSynchronized(cookie, lock, self);
1583  } else {
1584    JniMethodEnd(cookie, self);
1585  }
1586}
1587
1588/*
1589 * Initializes an alloca region assumed to be directly below sp for a native call:
1590 * Create a HandleScope and call stack and fill a mini stack with values to be pushed to registers.
1591 * The final element on the stack is a pointer to the native code.
1592 *
1593 * On entry, the stack has a standard callee-save frame above sp, and an alloca below it.
1594 * We need to fix this, as the handle scope needs to go into the callee-save frame.
1595 *
1596 * The return of this function denotes:
1597 * 1) How many bytes of the alloca can be released, if the value is non-negative.
1598 * 2) An error, if the value is negative.
1599 */
1600extern "C" TwoWordReturn artQuickGenericJniTrampoline(Thread* self,
1601                                                      StackReference<mirror::ArtMethod>* sp)
1602    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1603  mirror::ArtMethod* called = sp->AsMirrorPtr();
1604  DCHECK(called->IsNative()) << PrettyMethod(called, true);
1605  uint32_t shorty_len = 0;
1606  const char* shorty = called->GetShorty(&shorty_len);
1607
1608  // Run the visitor.
1609  BuildGenericJniFrameVisitor visitor(&sp, called->IsStatic(), shorty, shorty_len, self);
1610  visitor.VisitArguments();
1611  visitor.FinalizeHandleScope(self);
1612
1613  // Fix up managed-stack things in Thread.
1614  self->SetTopOfStack(sp, 0);
1615
1616  self->VerifyStack();
1617
1618  // Start JNI, save the cookie.
1619  uint32_t cookie;
1620  if (called->IsSynchronized()) {
1621    cookie = JniMethodStartSynchronized(visitor.GetFirstHandleScopeJObject(), self);
1622    if (self->IsExceptionPending()) {
1623      self->PopHandleScope();
1624      // A negative value denotes an error.
1625      return GetTwoWordFailureValue();
1626    }
1627  } else {
1628    cookie = JniMethodStart(self);
1629  }
1630  uint32_t* sp32 = reinterpret_cast<uint32_t*>(sp);
1631  *(sp32 - 1) = cookie;
1632
1633  // Retrieve the stored native code.
1634  const void* nativeCode = called->GetNativeMethod();
1635
1636  // There are two cases for the content of nativeCode:
1637  // 1) Pointer to the native function.
1638  // 2) Pointer to the trampoline for native code binding.
1639  // In the second case, we need to execute the binding and continue with the actual native function
1640  // pointer.
1641  DCHECK(nativeCode != nullptr);
1642  if (nativeCode == GetJniDlsymLookupStub()) {
1643#if defined(__arm__) || defined(__aarch64__)
1644    nativeCode = artFindNativeMethod();
1645#else
1646    nativeCode = artFindNativeMethod(self);
1647#endif
1648
1649    if (nativeCode == nullptr) {
1650      DCHECK(self->IsExceptionPending());    // There should be an exception pending now.
1651
1652      // End JNI, as the assembly will move to deliver the exception.
1653      jobject lock = called->IsSynchronized() ? visitor.GetFirstHandleScopeJObject() : nullptr;
1654      if (shorty[0] == 'L') {
1655        artQuickGenericJniEndJNIRef(self, cookie, nullptr, lock);
1656      } else {
1657        artQuickGenericJniEndJNINonRef(self, cookie, lock);
1658      }
1659
1660      return GetTwoWordFailureValue();
1661    }
1662    // Note that the native code pointer will be automatically set by artFindNativeMethod().
1663  }
1664
1665  // Return native code addr(lo) and bottom of alloca address(hi).
1666  return GetTwoWordSuccessValue(reinterpret_cast<uintptr_t>(visitor.GetBottomOfUsedArea()),
1667                                reinterpret_cast<uintptr_t>(nativeCode));
1668}
1669
1670/*
1671 * Is called after the native JNI code. Responsible for cleanup (handle scope, saved state) and
1672 * unlocking.
1673 */
1674extern "C" uint64_t artQuickGenericJniEndTrampoline(Thread* self, jvalue result, uint64_t result_f)
1675    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1676  StackReference<mirror::ArtMethod>* sp = self->GetManagedStack()->GetTopQuickFrame();
1677  uint32_t* sp32 = reinterpret_cast<uint32_t*>(sp);
1678  mirror::ArtMethod* called = sp->AsMirrorPtr();
1679  uint32_t cookie = *(sp32 - 1);
1680
1681  jobject lock = nullptr;
1682  if (called->IsSynchronized()) {
1683    HandleScope* table = reinterpret_cast<HandleScope*>(reinterpret_cast<uint8_t*>(sp)
1684        + sizeof(StackReference<mirror::ArtMethod>));
1685    lock = table->GetHandle(0).ToJObject();
1686  }
1687
1688  char return_shorty_char = called->GetShorty()[0];
1689
1690  if (return_shorty_char == 'L') {
1691    return artQuickGenericJniEndJNIRef(self, cookie, result.l, lock);
1692  } else {
1693    artQuickGenericJniEndJNINonRef(self, cookie, lock);
1694
1695    switch (return_shorty_char) {
1696      case 'F':  // Fall-through.
1697      case 'D':
1698        return result_f;
1699      case 'Z':
1700        return result.z;
1701      case 'B':
1702        return result.b;
1703      case 'C':
1704        return result.c;
1705      case 'S':
1706        return result.s;
1707      case 'I':
1708        return result.i;
1709      case 'J':
1710        return result.j;
1711      case 'V':
1712        return 0;
1713      default:
1714        LOG(FATAL) << "Unexpected return shorty character " << return_shorty_char;
1715        return 0;
1716    }
1717  }
1718}
1719
1720// We use TwoWordReturn to optimize scalar returns. We use the hi value for code, and the lo value
1721// for the method pointer.
1722//
1723// It is valid to use this, as at the usage points here (returns from C functions) we are assuming
1724// to hold the mutator lock (see SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) annotations).
1725
1726template<InvokeType type, bool access_check>
1727static TwoWordReturn artInvokeCommon(uint32_t method_idx, mirror::Object* this_object,
1728                                     mirror::ArtMethod* caller_method,
1729                                     Thread* self, StackReference<mirror::ArtMethod>* sp);
1730
1731template<InvokeType type, bool access_check>
1732static TwoWordReturn artInvokeCommon(uint32_t method_idx, mirror::Object* this_object,
1733                                     mirror::ArtMethod* caller_method,
1734                                     Thread* self, StackReference<mirror::ArtMethod>* sp) {
1735  mirror::ArtMethod* method = FindMethodFast(method_idx, this_object, caller_method, access_check,
1736                                             type);
1737  if (UNLIKELY(method == nullptr)) {
1738    FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsAndArgs);
1739    const DexFile* dex_file = caller_method->GetDeclaringClass()->GetDexCache()->GetDexFile();
1740    uint32_t shorty_len;
1741    const char* shorty = dex_file->GetMethodShorty(dex_file->GetMethodId(method_idx), &shorty_len);
1742    {
1743      // Remember the args in case a GC happens in FindMethodFromCode.
1744      ScopedObjectAccessUnchecked soa(self->GetJniEnv());
1745      RememberForGcArgumentVisitor visitor(sp, type == kStatic, shorty, shorty_len, &soa);
1746      visitor.VisitArguments();
1747      method = FindMethodFromCode<type, access_check>(method_idx, &this_object, &caller_method,
1748                                                      self);
1749      visitor.FixupReferences();
1750    }
1751
1752    if (UNLIKELY(method == NULL)) {
1753      CHECK(self->IsExceptionPending());
1754      return GetTwoWordFailureValue();  // Failure.
1755    }
1756  }
1757  DCHECK(!self->IsExceptionPending());
1758  const void* code = method->GetEntryPointFromQuickCompiledCode();
1759
1760  // When we return, the caller will branch to this address, so it had better not be 0!
1761  DCHECK(code != nullptr) << "Code was NULL in method: " << PrettyMethod(method)
1762                          << " location: "
1763                          << method->GetDexFile()->GetLocation();
1764
1765  return GetTwoWordSuccessValue(reinterpret_cast<uintptr_t>(code),
1766                                reinterpret_cast<uintptr_t>(method));
1767}
1768
1769// Explicit artInvokeCommon template function declarations to please analysis tool.
1770#define EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(type, access_check)                                \
1771  template SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)                                          \
1772  TwoWordReturn artInvokeCommon<type, access_check>(uint32_t method_idx,                        \
1773                                                    mirror::Object* this_object,                \
1774                                                    mirror::ArtMethod* caller_method,           \
1775                                                    Thread* self,                               \
1776                                                    StackReference<mirror::ArtMethod>* sp)      \
1777
1778EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kVirtual, false);
1779EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kVirtual, true);
1780EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kInterface, false);
1781EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kInterface, true);
1782EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kDirect, false);
1783EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kDirect, true);
1784EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kStatic, false);
1785EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kStatic, true);
1786EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kSuper, false);
1787EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL(kSuper, true);
1788#undef EXPLICIT_INVOKE_COMMON_TEMPLATE_DECL
1789
1790// See comments in runtime_support_asm.S
1791extern "C" TwoWordReturn artInvokeInterfaceTrampolineWithAccessCheck(
1792    uint32_t method_idx, mirror::Object* this_object,
1793    mirror::ArtMethod* caller_method, Thread* self,
1794    StackReference<mirror::ArtMethod>* sp)
1795        SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1796  return artInvokeCommon<kInterface, true>(method_idx, this_object,
1797                                           caller_method, self, sp);
1798}
1799
1800extern "C" TwoWordReturn artInvokeDirectTrampolineWithAccessCheck(
1801    uint32_t method_idx, mirror::Object* this_object,
1802    mirror::ArtMethod* caller_method, Thread* self,
1803    StackReference<mirror::ArtMethod>* sp)
1804        SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1805  return artInvokeCommon<kDirect, true>(method_idx, this_object, caller_method,
1806                                        self, sp);
1807}
1808
1809extern "C" TwoWordReturn artInvokeStaticTrampolineWithAccessCheck(
1810    uint32_t method_idx, mirror::Object* this_object,
1811    mirror::ArtMethod* caller_method, Thread* self,
1812    StackReference<mirror::ArtMethod>* sp)
1813        SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1814  return artInvokeCommon<kStatic, true>(method_idx, this_object, caller_method,
1815                                        self, sp);
1816}
1817
1818extern "C" TwoWordReturn artInvokeSuperTrampolineWithAccessCheck(
1819    uint32_t method_idx, mirror::Object* this_object,
1820    mirror::ArtMethod* caller_method, Thread* self,
1821    StackReference<mirror::ArtMethod>* sp)
1822        SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1823  return artInvokeCommon<kSuper, true>(method_idx, this_object, caller_method,
1824                                       self, sp);
1825}
1826
1827extern "C" TwoWordReturn artInvokeVirtualTrampolineWithAccessCheck(
1828    uint32_t method_idx, mirror::Object* this_object,
1829    mirror::ArtMethod* caller_method, Thread* self,
1830    StackReference<mirror::ArtMethod>* sp)
1831        SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1832  return artInvokeCommon<kVirtual, true>(method_idx, this_object, caller_method,
1833                                         self, sp);
1834}
1835
1836// Determine target of interface dispatch. This object is known non-null.
1837extern "C" TwoWordReturn artInvokeInterfaceTrampoline(mirror::ArtMethod* interface_method,
1838                                                      mirror::Object* this_object,
1839                                                      mirror::ArtMethod* caller_method,
1840                                                      Thread* self,
1841                                                      StackReference<mirror::ArtMethod>* sp)
1842    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1843  mirror::ArtMethod* method;
1844  if (LIKELY(interface_method->GetDexMethodIndex() != DexFile::kDexNoIndex)) {
1845    method = this_object->GetClass()->FindVirtualMethodForInterface(interface_method);
1846    if (UNLIKELY(method == NULL)) {
1847      FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsAndArgs);
1848      ThrowIncompatibleClassChangeErrorClassForInterfaceDispatch(interface_method, this_object,
1849                                                                 caller_method);
1850      return GetTwoWordFailureValue();  // Failure.
1851    }
1852  } else {
1853    FinishCalleeSaveFrameSetup(self, sp, Runtime::kRefsAndArgs);
1854    DCHECK(interface_method == Runtime::Current()->GetResolutionMethod());
1855
1856    // Find the caller PC.
1857    constexpr size_t pc_offset = GetCalleeSavePCOffset(kRuntimeISA, Runtime::kRefsAndArgs);
1858    uintptr_t caller_pc = *reinterpret_cast<uintptr_t*>(reinterpret_cast<byte*>(sp) + pc_offset);
1859
1860    // Map the caller PC to a dex PC.
1861    uint32_t dex_pc = caller_method->ToDexPc(caller_pc);
1862    const DexFile::CodeItem* code = caller_method->GetCodeItem();
1863    CHECK_LT(dex_pc, code->insns_size_in_code_units_);
1864    const Instruction* instr = Instruction::At(&code->insns_[dex_pc]);
1865    Instruction::Code instr_code = instr->Opcode();
1866    CHECK(instr_code == Instruction::INVOKE_INTERFACE ||
1867          instr_code == Instruction::INVOKE_INTERFACE_RANGE)
1868        << "Unexpected call into interface trampoline: " << instr->DumpString(NULL);
1869    uint32_t dex_method_idx;
1870    if (instr_code == Instruction::INVOKE_INTERFACE) {
1871      dex_method_idx = instr->VRegB_35c();
1872    } else {
1873      DCHECK_EQ(instr_code, Instruction::INVOKE_INTERFACE_RANGE);
1874      dex_method_idx = instr->VRegB_3rc();
1875    }
1876
1877    const DexFile* dex_file = caller_method->GetDeclaringClass()->GetDexCache()
1878        ->GetDexFile();
1879    uint32_t shorty_len;
1880    const char* shorty = dex_file->GetMethodShorty(dex_file->GetMethodId(dex_method_idx),
1881                                                   &shorty_len);
1882    {
1883      // Remember the args in case a GC happens in FindMethodFromCode.
1884      ScopedObjectAccessUnchecked soa(self->GetJniEnv());
1885      RememberForGcArgumentVisitor visitor(sp, false, shorty, shorty_len, &soa);
1886      visitor.VisitArguments();
1887      method = FindMethodFromCode<kInterface, false>(dex_method_idx, &this_object, &caller_method,
1888                                                     self);
1889      visitor.FixupReferences();
1890    }
1891
1892    if (UNLIKELY(method == nullptr)) {
1893      CHECK(self->IsExceptionPending());
1894      return GetTwoWordFailureValue();  // Failure.
1895    }
1896  }
1897  const void* code = method->GetEntryPointFromQuickCompiledCode();
1898
1899  // When we return, the caller will branch to this address, so it had better not be 0!
1900  DCHECK(code != nullptr) << "Code was NULL in method: " << PrettyMethod(method)
1901                          << " location: " << method->GetDexFile()->GetLocation();
1902
1903  return GetTwoWordSuccessValue(reinterpret_cast<uintptr_t>(code),
1904                                reinterpret_cast<uintptr_t>(method));
1905}
1906
1907}  // namespace art
1908