stack.cc revision 524e7ea8cd17bad17bd9f3e0ccbb19ad0d4d9c02 
1/*
2 * Copyright (C) 2011 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 "stack.h"
18
19#include "arch/context.h"
20#include "art_method-inl.h"
21#include "base/hex_dump.h"
22#include "entrypoints/entrypoint_utils-inl.h"
23#include "entrypoints/runtime_asm_entrypoints.h"
24#include "gc_map.h"
25#include "gc/space/image_space.h"
26#include "gc/space/space-inl.h"
27#include "jit/jit.h"
28#include "jit/jit_code_cache.h"
29#include "linear_alloc.h"
30#include "mirror/class-inl.h"
31#include "mirror/object-inl.h"
32#include "mirror/object_array-inl.h"
33#include "oat_quick_method_header.h"
34#include "quick/quick_method_frame_info.h"
35#include "runtime.h"
36#include "thread.h"
37#include "thread_list.h"
38#include "verify_object-inl.h"
39#include "vmap_table.h"
40
41namespace art {
42
43static constexpr bool kDebugStackWalk = false;
44
45mirror::Object* ShadowFrame::GetThisObject() const {
46  ArtMethod* m = GetMethod();
47  if (m->IsStatic()) {
48    return nullptr;
49  } else if (m->IsNative()) {
50    return GetVRegReference(0);
51  } else {
52    const DexFile::CodeItem* code_item = m->GetCodeItem();
53    CHECK(code_item != nullptr) << PrettyMethod(m);
54    uint16_t reg = code_item->registers_size_ - code_item->ins_size_;
55    return GetVRegReference(reg);
56  }
57}
58
59mirror::Object* ShadowFrame::GetThisObject(uint16_t num_ins) const {
60  ArtMethod* m = GetMethod();
61  if (m->IsStatic()) {
62    return nullptr;
63  } else {
64    return GetVRegReference(NumberOfVRegs() - num_ins);
65  }
66}
67
68size_t ManagedStack::NumJniShadowFrameReferences() const {
69  size_t count = 0;
70  for (const ManagedStack* current_fragment = this; current_fragment != nullptr;
71       current_fragment = current_fragment->GetLink()) {
72    for (ShadowFrame* current_frame = current_fragment->top_shadow_frame_; current_frame != nullptr;
73         current_frame = current_frame->GetLink()) {
74      if (current_frame->GetMethod()->IsNative()) {
75        // The JNI ShadowFrame only contains references. (For indirect reference.)
76        count += current_frame->NumberOfVRegs();
77      }
78    }
79  }
80  return count;
81}
82
83bool ManagedStack::ShadowFramesContain(StackReference<mirror::Object>* shadow_frame_entry) const {
84  for (const ManagedStack* current_fragment = this; current_fragment != nullptr;
85       current_fragment = current_fragment->GetLink()) {
86    for (ShadowFrame* current_frame = current_fragment->top_shadow_frame_; current_frame != nullptr;
87         current_frame = current_frame->GetLink()) {
88      if (current_frame->Contains(shadow_frame_entry)) {
89        return true;
90      }
91    }
92  }
93  return false;
94}
95
96StackVisitor::StackVisitor(Thread* thread, Context* context, StackWalkKind walk_kind)
97    : StackVisitor(thread, context, walk_kind, 0) {}
98
99StackVisitor::StackVisitor(Thread* thread,
100                           Context* context,
101                           StackWalkKind walk_kind,
102                           size_t num_frames)
103    : thread_(thread),
104      walk_kind_(walk_kind),
105      cur_shadow_frame_(nullptr),
106      cur_quick_frame_(nullptr),
107      cur_quick_frame_pc_(0),
108      cur_oat_quick_method_header_(nullptr),
109      num_frames_(num_frames),
110      cur_depth_(0),
111      current_inlining_depth_(0),
112      context_(context) {
113  DCHECK(thread == Thread::Current() || thread->IsSuspended()) << *thread;
114}
115
116InlineInfo StackVisitor::GetCurrentInlineInfo() const {
117  const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader();
118  uint32_t native_pc_offset = method_header->NativeQuickPcOffset(cur_quick_frame_pc_);
119  CodeInfo code_info = method_header->GetOptimizedCodeInfo();
120  StackMapEncoding encoding = code_info.ExtractEncoding();
121  StackMap stack_map = code_info.GetStackMapForNativePcOffset(native_pc_offset, encoding);
122  DCHECK(stack_map.IsValid());
123  return code_info.GetInlineInfoOf(stack_map, encoding);
124}
125
126ArtMethod* StackVisitor::GetMethod() const {
127  if (cur_shadow_frame_ != nullptr) {
128    return cur_shadow_frame_->GetMethod();
129  } else if (cur_quick_frame_ != nullptr) {
130    if (IsInInlinedFrame()) {
131      size_t depth_in_stack_map = current_inlining_depth_ - 1;
132      InlineInfo inline_info = GetCurrentInlineInfo();
133      return GetResolvedMethod(*GetCurrentQuickFrame(), inline_info, depth_in_stack_map);
134    } else {
135      return *cur_quick_frame_;
136    }
137  }
138  return nullptr;
139}
140
141uint32_t StackVisitor::GetDexPc(bool abort_on_failure) const {
142  if (cur_shadow_frame_ != nullptr) {
143    return cur_shadow_frame_->GetDexPC();
144  } else if (cur_quick_frame_ != nullptr) {
145    if (IsInInlinedFrame()) {
146      size_t depth_in_stack_map = current_inlining_depth_ - 1;
147      return GetCurrentInlineInfo().GetDexPcAtDepth(depth_in_stack_map);
148    } else if (cur_oat_quick_method_header_ == nullptr) {
149      return DexFile::kDexNoIndex;
150    } else {
151      return cur_oat_quick_method_header_->ToDexPc(
152          GetMethod(), cur_quick_frame_pc_, abort_on_failure);
153    }
154  } else {
155    return 0;
156  }
157}
158
159extern "C" mirror::Object* artQuickGetProxyThisObject(ArtMethod** sp)
160    SHARED_REQUIRES(Locks::mutator_lock_);
161
162mirror::Object* StackVisitor::GetThisObject() const {
163  DCHECK_EQ(Runtime::Current()->GetClassLinker()->GetImagePointerSize(), sizeof(void*));
164  ArtMethod* m = GetMethod();
165  if (m->IsStatic()) {
166    return nullptr;
167  } else if (m->IsNative()) {
168    if (cur_quick_frame_ != nullptr) {
169      HandleScope* hs = reinterpret_cast<HandleScope*>(
170          reinterpret_cast<char*>(cur_quick_frame_) + sizeof(ArtMethod*));
171      return hs->GetReference(0);
172    } else {
173      return cur_shadow_frame_->GetVRegReference(0);
174    }
175  } else if (m->IsProxyMethod()) {
176    if (cur_quick_frame_ != nullptr) {
177      return artQuickGetProxyThisObject(cur_quick_frame_);
178    } else {
179      return cur_shadow_frame_->GetVRegReference(0);
180    }
181  } else {
182    const DexFile::CodeItem* code_item = m->GetCodeItem();
183    if (code_item == nullptr) {
184      UNIMPLEMENTED(ERROR) << "Failed to determine this object of abstract or proxy method: "
185          << PrettyMethod(m);
186      return nullptr;
187    } else {
188      uint16_t reg = code_item->registers_size_ - code_item->ins_size_;
189      uint32_t value = 0;
190      bool success = GetVReg(m, reg, kReferenceVReg, &value);
191      // We currently always guarantee the `this` object is live throughout the method.
192      CHECK(success) << "Failed to read the this object in " << PrettyMethod(m);
193      return reinterpret_cast<mirror::Object*>(value);
194    }
195  }
196}
197
198size_t StackVisitor::GetNativePcOffset() const {
199  DCHECK(!IsShadowFrame());
200  return GetCurrentOatQuickMethodHeader()->NativeQuickPcOffset(cur_quick_frame_pc_);
201}
202
203bool StackVisitor::IsReferenceVReg(ArtMethod* m, uint16_t vreg) {
204  DCHECK_EQ(m, GetMethod());
205  // Process register map (which native and runtime methods don't have)
206  if (m->IsNative() || m->IsRuntimeMethod() || m->IsProxyMethod()) {
207    return false;
208  }
209  const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader();
210  if (method_header->IsOptimized()) {
211    return true;  // TODO: Implement.
212  }
213  const uint8_t* native_gc_map = method_header->GetNativeGcMap();
214  CHECK(native_gc_map != nullptr) << PrettyMethod(m);
215  const DexFile::CodeItem* code_item = m->GetCodeItem();
216  // Can't be null or how would we compile its instructions?
217  DCHECK(code_item != nullptr) << PrettyMethod(m);
218  NativePcOffsetToReferenceMap map(native_gc_map);
219  size_t num_regs = std::min(map.RegWidth() * 8, static_cast<size_t>(code_item->registers_size_));
220  const uint8_t* reg_bitmap = nullptr;
221  if (num_regs > 0) {
222    uintptr_t native_pc_offset = method_header->NativeQuickPcOffset(GetCurrentQuickFramePc());
223    reg_bitmap = map.FindBitMap(native_pc_offset);
224    DCHECK(reg_bitmap != nullptr);
225  }
226  // Does this register hold a reference?
227  return vreg < num_regs && TestBitmap(vreg, reg_bitmap);
228}
229
230bool StackVisitor::GetVRegFromDebuggerShadowFrame(uint16_t vreg,
231                                                  VRegKind kind,
232                                                  uint32_t* val) const {
233  size_t frame_id = const_cast<StackVisitor*>(this)->GetFrameId();
234  ShadowFrame* shadow_frame = thread_->FindDebuggerShadowFrame(frame_id);
235  if (shadow_frame != nullptr) {
236    bool* updated_vreg_flags = thread_->GetUpdatedVRegFlags(frame_id);
237    DCHECK(updated_vreg_flags != nullptr);
238    if (updated_vreg_flags[vreg]) {
239      // Value is set by the debugger.
240      if (kind == kReferenceVReg) {
241        *val = static_cast<uint32_t>(reinterpret_cast<uintptr_t>(
242            shadow_frame->GetVRegReference(vreg)));
243      } else {
244        *val = shadow_frame->GetVReg(vreg);
245      }
246      return true;
247    }
248  }
249  // No value is set by the debugger.
250  return false;
251}
252
253bool StackVisitor::GetVReg(ArtMethod* m, uint16_t vreg, VRegKind kind, uint32_t* val) const {
254  if (cur_quick_frame_ != nullptr) {
255    DCHECK(context_ != nullptr);  // You can't reliably read registers without a context.
256    DCHECK(m == GetMethod());
257    // Check if there is value set by the debugger.
258    if (GetVRegFromDebuggerShadowFrame(vreg, kind, val)) {
259      return true;
260    }
261    if (cur_oat_quick_method_header_->IsOptimized()) {
262      return GetVRegFromOptimizedCode(m, vreg, kind, val);
263    } else {
264      return GetVRegFromQuickCode(m, vreg, kind, val);
265    }
266  } else {
267    DCHECK(cur_shadow_frame_ != nullptr);
268    *val = cur_shadow_frame_->GetVReg(vreg);
269    return true;
270  }
271}
272
273bool StackVisitor::GetVRegFromQuickCode(ArtMethod* m, uint16_t vreg, VRegKind kind,
274                                        uint32_t* val) const {
275  DCHECK_EQ(m, GetMethod());
276  const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader();
277  QuickMethodFrameInfo frame_info = method_header->GetFrameInfo();
278  const VmapTable vmap_table(method_header->GetVmapTable());
279  uint32_t vmap_offset;
280  // TODO: IsInContext stops before spotting floating point registers.
281  if (vmap_table.IsInContext(vreg, kind, &vmap_offset)) {
282    bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg);
283    uint32_t spill_mask = is_float ? frame_info.FpSpillMask() : frame_info.CoreSpillMask();
284    uint32_t reg = vmap_table.ComputeRegister(spill_mask, vmap_offset, kind);
285    return GetRegisterIfAccessible(reg, kind, val);
286  } else {
287    const DexFile::CodeItem* code_item = m->GetCodeItem();
288    DCHECK(code_item != nullptr) << PrettyMethod(m);  // Can't be null or how would we compile
289                                                      // its instructions?
290    *val = *GetVRegAddrFromQuickCode(cur_quick_frame_, code_item, frame_info.CoreSpillMask(),
291                                     frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), vreg);
292    return true;
293  }
294}
295
296bool StackVisitor::GetVRegFromOptimizedCode(ArtMethod* m, uint16_t vreg, VRegKind kind,
297                                            uint32_t* val) const {
298  DCHECK_EQ(m, GetMethod());
299  const DexFile::CodeItem* code_item = m->GetCodeItem();
300  DCHECK(code_item != nullptr) << PrettyMethod(m);  // Can't be null or how would we compile
301                                                    // its instructions?
302  uint16_t number_of_dex_registers = code_item->registers_size_;
303  DCHECK_LT(vreg, code_item->registers_size_);
304  const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader();
305  CodeInfo code_info = method_header->GetOptimizedCodeInfo();
306  StackMapEncoding encoding = code_info.ExtractEncoding();
307
308  uint32_t native_pc_offset = method_header->NativeQuickPcOffset(cur_quick_frame_pc_);
309  StackMap stack_map = code_info.GetStackMapForNativePcOffset(native_pc_offset, encoding);
310  DCHECK(stack_map.IsValid());
311  size_t depth_in_stack_map = current_inlining_depth_ - 1;
312
313  DexRegisterMap dex_register_map = IsInInlinedFrame()
314      ? code_info.GetDexRegisterMapAtDepth(depth_in_stack_map,
315                                           code_info.GetInlineInfoOf(stack_map, encoding),
316                                           encoding,
317                                           number_of_dex_registers)
318      : code_info.GetDexRegisterMapOf(stack_map, encoding, number_of_dex_registers);
319
320  DexRegisterLocation::Kind location_kind =
321      dex_register_map.GetLocationKind(vreg, number_of_dex_registers, code_info, encoding);
322  switch (location_kind) {
323    case DexRegisterLocation::Kind::kInStack: {
324      const int32_t offset = dex_register_map.GetStackOffsetInBytes(vreg,
325                                                                    number_of_dex_registers,
326                                                                    code_info,
327                                                                    encoding);
328      const uint8_t* addr = reinterpret_cast<const uint8_t*>(cur_quick_frame_) + offset;
329      *val = *reinterpret_cast<const uint32_t*>(addr);
330      return true;
331    }
332    case DexRegisterLocation::Kind::kInRegister:
333    case DexRegisterLocation::Kind::kInRegisterHigh:
334    case DexRegisterLocation::Kind::kInFpuRegister:
335    case DexRegisterLocation::Kind::kInFpuRegisterHigh: {
336      uint32_t reg =
337          dex_register_map.GetMachineRegister(vreg, number_of_dex_registers, code_info, encoding);
338      return GetRegisterIfAccessible(reg, kind, val);
339    }
340    case DexRegisterLocation::Kind::kConstant:
341      *val = dex_register_map.GetConstant(vreg, number_of_dex_registers, code_info, encoding);
342      return true;
343    case DexRegisterLocation::Kind::kNone:
344      return false;
345    default:
346      LOG(FATAL)
347          << "Unexpected location kind"
348          << DexRegisterLocation::PrettyDescriptor(
349                dex_register_map.GetLocationInternalKind(vreg,
350                                                         number_of_dex_registers,
351                                                         code_info,
352                                                         encoding));
353      UNREACHABLE();
354  }
355}
356
357bool StackVisitor::GetRegisterIfAccessible(uint32_t reg, VRegKind kind, uint32_t* val) const {
358  const bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg);
359
360  // X86 float registers are 64-bit and the logic below does not apply.
361  DCHECK(!is_float || kRuntimeISA != InstructionSet::kX86);
362
363  if (!IsAccessibleRegister(reg, is_float)) {
364    return false;
365  }
366  uintptr_t ptr_val = GetRegister(reg, is_float);
367  const bool target64 = Is64BitInstructionSet(kRuntimeISA);
368  if (target64) {
369    const bool wide_lo = (kind == kLongLoVReg) || (kind == kDoubleLoVReg);
370    const bool wide_hi = (kind == kLongHiVReg) || (kind == kDoubleHiVReg);
371    int64_t value_long = static_cast<int64_t>(ptr_val);
372    if (wide_lo) {
373      ptr_val = static_cast<uintptr_t>(Low32Bits(value_long));
374    } else if (wide_hi) {
375      ptr_val = static_cast<uintptr_t>(High32Bits(value_long));
376    }
377  }
378  *val = ptr_val;
379  return true;
380}
381
382bool StackVisitor::GetVRegPairFromDebuggerShadowFrame(uint16_t vreg,
383                                                      VRegKind kind_lo,
384                                                      VRegKind kind_hi,
385                                                      uint64_t* val) const {
386  uint32_t low_32bits;
387  uint32_t high_32bits;
388  bool success = GetVRegFromDebuggerShadowFrame(vreg, kind_lo, &low_32bits);
389  success &= GetVRegFromDebuggerShadowFrame(vreg + 1, kind_hi, &high_32bits);
390  if (success) {
391    *val = (static_cast<uint64_t>(high_32bits) << 32) | static_cast<uint64_t>(low_32bits);
392  }
393  return success;
394}
395
396bool StackVisitor::GetVRegPair(ArtMethod* m, uint16_t vreg, VRegKind kind_lo,
397                               VRegKind kind_hi, uint64_t* val) const {
398  if (kind_lo == kLongLoVReg) {
399    DCHECK_EQ(kind_hi, kLongHiVReg);
400  } else if (kind_lo == kDoubleLoVReg) {
401    DCHECK_EQ(kind_hi, kDoubleHiVReg);
402  } else {
403    LOG(FATAL) << "Expected long or double: kind_lo=" << kind_lo << ", kind_hi=" << kind_hi;
404    UNREACHABLE();
405  }
406  // Check if there is value set by the debugger.
407  if (GetVRegPairFromDebuggerShadowFrame(vreg, kind_lo, kind_hi, val)) {
408    return true;
409  }
410  if (cur_quick_frame_ != nullptr) {
411    DCHECK(context_ != nullptr);  // You can't reliably read registers without a context.
412    DCHECK(m == GetMethod());
413    if (cur_oat_quick_method_header_->IsOptimized()) {
414      return GetVRegPairFromOptimizedCode(m, vreg, kind_lo, kind_hi, val);
415    } else {
416      return GetVRegPairFromQuickCode(m, vreg, kind_lo, kind_hi, val);
417    }
418  } else {
419    DCHECK(cur_shadow_frame_ != nullptr);
420    *val = cur_shadow_frame_->GetVRegLong(vreg);
421    return true;
422  }
423}
424
425bool StackVisitor::GetVRegPairFromQuickCode(ArtMethod* m, uint16_t vreg, VRegKind kind_lo,
426                                            VRegKind kind_hi, uint64_t* val) const {
427  DCHECK_EQ(m, GetMethod());
428  const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader();
429  QuickMethodFrameInfo frame_info = method_header->GetFrameInfo();
430  const VmapTable vmap_table(method_header->GetVmapTable());
431  uint32_t vmap_offset_lo, vmap_offset_hi;
432  // TODO: IsInContext stops before spotting floating point registers.
433  if (vmap_table.IsInContext(vreg, kind_lo, &vmap_offset_lo) &&
434      vmap_table.IsInContext(vreg + 1, kind_hi, &vmap_offset_hi)) {
435    bool is_float = (kind_lo == kDoubleLoVReg);
436    uint32_t spill_mask = is_float ? frame_info.FpSpillMask() : frame_info.CoreSpillMask();
437    uint32_t reg_lo = vmap_table.ComputeRegister(spill_mask, vmap_offset_lo, kind_lo);
438    uint32_t reg_hi = vmap_table.ComputeRegister(spill_mask, vmap_offset_hi, kind_hi);
439    return GetRegisterPairIfAccessible(reg_lo, reg_hi, kind_lo, val);
440  } else {
441    const DexFile::CodeItem* code_item = m->GetCodeItem();
442    DCHECK(code_item != nullptr) << PrettyMethod(m);  // Can't be null or how would we compile
443                                                      // its instructions?
444    uint32_t* addr = GetVRegAddrFromQuickCode(
445        cur_quick_frame_, code_item, frame_info.CoreSpillMask(),
446        frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), vreg);
447    *val = *reinterpret_cast<uint64_t*>(addr);
448    return true;
449  }
450}
451
452bool StackVisitor::GetVRegPairFromOptimizedCode(ArtMethod* m, uint16_t vreg,
453                                                VRegKind kind_lo, VRegKind kind_hi,
454                                                uint64_t* val) const {
455  uint32_t low_32bits;
456  uint32_t high_32bits;
457  bool success = GetVRegFromOptimizedCode(m, vreg, kind_lo, &low_32bits);
458  success &= GetVRegFromOptimizedCode(m, vreg + 1, kind_hi, &high_32bits);
459  if (success) {
460    *val = (static_cast<uint64_t>(high_32bits) << 32) | static_cast<uint64_t>(low_32bits);
461  }
462  return success;
463}
464
465bool StackVisitor::GetRegisterPairIfAccessible(uint32_t reg_lo, uint32_t reg_hi,
466                                               VRegKind kind_lo, uint64_t* val) const {
467  const bool is_float = (kind_lo == kDoubleLoVReg);
468  if (!IsAccessibleRegister(reg_lo, is_float) || !IsAccessibleRegister(reg_hi, is_float)) {
469    return false;
470  }
471  uintptr_t ptr_val_lo = GetRegister(reg_lo, is_float);
472  uintptr_t ptr_val_hi = GetRegister(reg_hi, is_float);
473  bool target64 = Is64BitInstructionSet(kRuntimeISA);
474  if (target64) {
475    int64_t value_long_lo = static_cast<int64_t>(ptr_val_lo);
476    int64_t value_long_hi = static_cast<int64_t>(ptr_val_hi);
477    ptr_val_lo = static_cast<uintptr_t>(Low32Bits(value_long_lo));
478    ptr_val_hi = static_cast<uintptr_t>(High32Bits(value_long_hi));
479  }
480  *val = (static_cast<uint64_t>(ptr_val_hi) << 32) | static_cast<uint32_t>(ptr_val_lo);
481  return true;
482}
483
484bool StackVisitor::SetVReg(ArtMethod* m, uint16_t vreg, uint32_t new_value,
485                           VRegKind kind) {
486  if (cur_quick_frame_ != nullptr) {
487    DCHECK(context_ != nullptr);  // You can't reliably write registers without a context.
488    DCHECK(m == GetMethod());
489    if (cur_oat_quick_method_header_->IsOptimized()) {
490      return false;
491    } else {
492      return SetVRegFromQuickCode(m, vreg, new_value, kind);
493    }
494  } else {
495    cur_shadow_frame_->SetVReg(vreg, new_value);
496    return true;
497  }
498}
499
500bool StackVisitor::SetVRegFromQuickCode(ArtMethod* m, uint16_t vreg, uint32_t new_value,
501                                        VRegKind kind) {
502  DCHECK(context_ != nullptr);  // You can't reliably write registers without a context.
503  DCHECK(m == GetMethod());
504  const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader();
505  QuickMethodFrameInfo frame_info = method_header->GetFrameInfo();
506  const VmapTable vmap_table(method_header->GetVmapTable());
507  uint32_t vmap_offset;
508  // TODO: IsInContext stops before spotting floating point registers.
509  if (vmap_table.IsInContext(vreg, kind, &vmap_offset)) {
510    bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg);
511    uint32_t spill_mask = is_float ? frame_info.FpSpillMask() : frame_info.CoreSpillMask();
512    uint32_t reg = vmap_table.ComputeRegister(spill_mask, vmap_offset, kind);
513    return SetRegisterIfAccessible(reg, new_value, kind);
514  } else {
515    const DexFile::CodeItem* code_item = m->GetCodeItem();
516    DCHECK(code_item != nullptr) << PrettyMethod(m);  // Can't be null or how would we compile
517                                                      // its instructions?
518    uint32_t* addr = GetVRegAddrFromQuickCode(
519        cur_quick_frame_, code_item, frame_info.CoreSpillMask(),
520        frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), vreg);
521    *addr = new_value;
522    return true;
523  }
524}
525
526bool StackVisitor::SetVRegFromDebugger(ArtMethod* m,
527                                       uint16_t vreg,
528                                       uint32_t new_value,
529                                       VRegKind kind) {
530  const DexFile::CodeItem* code_item = m->GetCodeItem();
531  if (code_item == nullptr) {
532    return false;
533  }
534  ShadowFrame* shadow_frame = GetCurrentShadowFrame();
535  if (shadow_frame == nullptr) {
536    // This is a compiled frame: we must prepare and update a shadow frame that will
537    // be executed by the interpreter after deoptimization of the stack.
538    const size_t frame_id = GetFrameId();
539    const uint16_t num_regs = code_item->registers_size_;
540    shadow_frame = thread_->FindOrCreateDebuggerShadowFrame(frame_id, num_regs, m, GetDexPc());
541    CHECK(shadow_frame != nullptr);
542    // Remember the vreg has been set for debugging and must not be overwritten by the
543    // original value during deoptimization of the stack.
544    thread_->GetUpdatedVRegFlags(frame_id)[vreg] = true;
545  }
546  if (kind == kReferenceVReg) {
547    shadow_frame->SetVRegReference(vreg, reinterpret_cast<mirror::Object*>(new_value));
548  } else {
549    shadow_frame->SetVReg(vreg, new_value);
550  }
551  return true;
552}
553
554bool StackVisitor::SetRegisterIfAccessible(uint32_t reg, uint32_t new_value, VRegKind kind) {
555  const bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg);
556  if (!IsAccessibleRegister(reg, is_float)) {
557    return false;
558  }
559  const bool target64 = Is64BitInstructionSet(kRuntimeISA);
560
561  // Create a new value that can hold both low 32 and high 32 bits, in
562  // case we are running 64 bits.
563  uintptr_t full_new_value = new_value;
564  // Deal with 32 or 64-bit wide registers in a way that builds on all targets.
565  if (target64) {
566    bool wide_lo = (kind == kLongLoVReg) || (kind == kDoubleLoVReg);
567    bool wide_hi = (kind == kLongHiVReg) || (kind == kDoubleHiVReg);
568    if (wide_lo || wide_hi) {
569      uintptr_t old_reg_val = GetRegister(reg, is_float);
570      uint64_t new_vreg_portion = static_cast<uint64_t>(new_value);
571      uint64_t old_reg_val_as_wide = static_cast<uint64_t>(old_reg_val);
572      uint64_t mask = 0xffffffff;
573      if (wide_lo) {
574        mask = mask << 32;
575      } else {
576        new_vreg_portion = new_vreg_portion << 32;
577      }
578      full_new_value = static_cast<uintptr_t>((old_reg_val_as_wide & mask) | new_vreg_portion);
579    }
580  }
581  SetRegister(reg, full_new_value, is_float);
582  return true;
583}
584
585bool StackVisitor::SetVRegPair(ArtMethod* m, uint16_t vreg, uint64_t new_value,
586                               VRegKind kind_lo, VRegKind kind_hi) {
587  if (kind_lo == kLongLoVReg) {
588    DCHECK_EQ(kind_hi, kLongHiVReg);
589  } else if (kind_lo == kDoubleLoVReg) {
590    DCHECK_EQ(kind_hi, kDoubleHiVReg);
591  } else {
592    LOG(FATAL) << "Expected long or double: kind_lo=" << kind_lo << ", kind_hi=" << kind_hi;
593  }
594  if (cur_quick_frame_ != nullptr) {
595    DCHECK(context_ != nullptr);  // You can't reliably write registers without a context.
596    DCHECK(m == GetMethod());
597    if (cur_oat_quick_method_header_->IsOptimized()) {
598      return false;
599    } else {
600      return SetVRegPairFromQuickCode(m, vreg, new_value, kind_lo, kind_hi);
601    }
602  } else {
603    DCHECK(cur_shadow_frame_ != nullptr);
604    cur_shadow_frame_->SetVRegLong(vreg, new_value);
605    return true;
606  }
607}
608
609bool StackVisitor::SetVRegPairFromQuickCode(
610    ArtMethod* m, uint16_t vreg, uint64_t new_value, VRegKind kind_lo, VRegKind kind_hi) {
611  DCHECK_EQ(m, GetMethod());
612  const OatQuickMethodHeader* method_header = GetCurrentOatQuickMethodHeader();
613  QuickMethodFrameInfo frame_info = method_header->GetFrameInfo();
614  const VmapTable vmap_table(method_header->GetVmapTable());
615  uint32_t vmap_offset_lo, vmap_offset_hi;
616  // TODO: IsInContext stops before spotting floating point registers.
617  if (vmap_table.IsInContext(vreg, kind_lo, &vmap_offset_lo) &&
618      vmap_table.IsInContext(vreg + 1, kind_hi, &vmap_offset_hi)) {
619    bool is_float = (kind_lo == kDoubleLoVReg);
620    uint32_t spill_mask = is_float ? frame_info.FpSpillMask() : frame_info.CoreSpillMask();
621    uint32_t reg_lo = vmap_table.ComputeRegister(spill_mask, vmap_offset_lo, kind_lo);
622    uint32_t reg_hi = vmap_table.ComputeRegister(spill_mask, vmap_offset_hi, kind_hi);
623    return SetRegisterPairIfAccessible(reg_lo, reg_hi, new_value, is_float);
624  } else {
625    const DexFile::CodeItem* code_item = m->GetCodeItem();
626    DCHECK(code_item != nullptr) << PrettyMethod(m);  // Can't be null or how would we compile
627                                                      // its instructions?
628    uint32_t* addr = GetVRegAddrFromQuickCode(
629        cur_quick_frame_, code_item, frame_info.CoreSpillMask(),
630        frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), vreg);
631    *reinterpret_cast<uint64_t*>(addr) = new_value;
632    return true;
633  }
634}
635
636bool StackVisitor::SetVRegPairFromDebugger(ArtMethod* m,
637                                           uint16_t vreg,
638                                           uint64_t new_value,
639                                           VRegKind kind_lo,
640                                           VRegKind kind_hi) {
641  if (kind_lo == kLongLoVReg) {
642    DCHECK_EQ(kind_hi, kLongHiVReg);
643  } else if (kind_lo == kDoubleLoVReg) {
644    DCHECK_EQ(kind_hi, kDoubleHiVReg);
645  } else {
646    LOG(FATAL) << "Expected long or double: kind_lo=" << kind_lo << ", kind_hi=" << kind_hi;
647    UNREACHABLE();
648  }
649  const DexFile::CodeItem* code_item = m->GetCodeItem();
650  if (code_item == nullptr) {
651    return false;
652  }
653  ShadowFrame* shadow_frame = GetCurrentShadowFrame();
654  if (shadow_frame == nullptr) {
655    // This is a compiled frame: we must prepare for deoptimization (see SetVRegFromDebugger).
656    const size_t frame_id = GetFrameId();
657    const uint16_t num_regs = code_item->registers_size_;
658    shadow_frame = thread_->FindOrCreateDebuggerShadowFrame(frame_id, num_regs, m, GetDexPc());
659    CHECK(shadow_frame != nullptr);
660    // Remember the vreg pair has been set for debugging and must not be overwritten by the
661    // original value during deoptimization of the stack.
662    thread_->GetUpdatedVRegFlags(frame_id)[vreg] = true;
663    thread_->GetUpdatedVRegFlags(frame_id)[vreg + 1] = true;
664  }
665  shadow_frame->SetVRegLong(vreg, new_value);
666  return true;
667}
668
669bool StackVisitor::SetRegisterPairIfAccessible(uint32_t reg_lo, uint32_t reg_hi,
670                                               uint64_t new_value, bool is_float) {
671  if (!IsAccessibleRegister(reg_lo, is_float) || !IsAccessibleRegister(reg_hi, is_float)) {
672    return false;
673  }
674  uintptr_t new_value_lo = static_cast<uintptr_t>(new_value & 0xFFFFFFFF);
675  uintptr_t new_value_hi = static_cast<uintptr_t>(new_value >> 32);
676  bool target64 = Is64BitInstructionSet(kRuntimeISA);
677  // Deal with 32 or 64-bit wide registers in a way that builds on all targets.
678  if (target64) {
679    DCHECK_EQ(reg_lo, reg_hi);
680    SetRegister(reg_lo, new_value, is_float);
681  } else {
682    SetRegister(reg_lo, new_value_lo, is_float);
683    SetRegister(reg_hi, new_value_hi, is_float);
684  }
685  return true;
686}
687
688bool StackVisitor::IsAccessibleGPR(uint32_t reg) const {
689  DCHECK(context_ != nullptr);
690  return context_->IsAccessibleGPR(reg);
691}
692
693uintptr_t* StackVisitor::GetGPRAddress(uint32_t reg) const {
694  DCHECK(cur_quick_frame_ != nullptr) << "This is a quick frame routine";
695  DCHECK(context_ != nullptr);
696  return context_->GetGPRAddress(reg);
697}
698
699uintptr_t StackVisitor::GetGPR(uint32_t reg) const {
700  DCHECK(cur_quick_frame_ != nullptr) << "This is a quick frame routine";
701  DCHECK(context_ != nullptr);
702  return context_->GetGPR(reg);
703}
704
705void StackVisitor::SetGPR(uint32_t reg, uintptr_t value) {
706  DCHECK(cur_quick_frame_ != nullptr) << "This is a quick frame routine";
707  DCHECK(context_ != nullptr);
708  context_->SetGPR(reg, value);
709}
710
711bool StackVisitor::IsAccessibleFPR(uint32_t reg) const {
712  DCHECK(context_ != nullptr);
713  return context_->IsAccessibleFPR(reg);
714}
715
716uintptr_t StackVisitor::GetFPR(uint32_t reg) const {
717  DCHECK(cur_quick_frame_ != nullptr) << "This is a quick frame routine";
718  DCHECK(context_ != nullptr);
719  return context_->GetFPR(reg);
720}
721
722void StackVisitor::SetFPR(uint32_t reg, uintptr_t value) {
723  DCHECK(cur_quick_frame_ != nullptr) << "This is a quick frame routine";
724  DCHECK(context_ != nullptr);
725  context_->SetFPR(reg, value);
726}
727
728uintptr_t StackVisitor::GetReturnPc() const {
729  uint8_t* sp = reinterpret_cast<uint8_t*>(GetCurrentQuickFrame());
730  DCHECK(sp != nullptr);
731  uint8_t* pc_addr = sp + GetCurrentQuickFrameInfo().GetReturnPcOffset();
732  return *reinterpret_cast<uintptr_t*>(pc_addr);
733}
734
735void StackVisitor::SetReturnPc(uintptr_t new_ret_pc) {
736  uint8_t* sp = reinterpret_cast<uint8_t*>(GetCurrentQuickFrame());
737  CHECK(sp != nullptr);
738  uint8_t* pc_addr = sp + GetCurrentQuickFrameInfo().GetReturnPcOffset();
739  *reinterpret_cast<uintptr_t*>(pc_addr) = new_ret_pc;
740}
741
742size_t StackVisitor::ComputeNumFrames(Thread* thread, StackWalkKind walk_kind) {
743  struct NumFramesVisitor : public StackVisitor {
744    NumFramesVisitor(Thread* thread_in, StackWalkKind walk_kind_in)
745        : StackVisitor(thread_in, nullptr, walk_kind_in), frames(0) {}
746
747    bool VisitFrame() OVERRIDE {
748      frames++;
749      return true;
750    }
751
752    size_t frames;
753  };
754  NumFramesVisitor visitor(thread, walk_kind);
755  visitor.WalkStack(true);
756  return visitor.frames;
757}
758
759bool StackVisitor::GetNextMethodAndDexPc(ArtMethod** next_method, uint32_t* next_dex_pc) {
760  struct HasMoreFramesVisitor : public StackVisitor {
761    HasMoreFramesVisitor(Thread* thread,
762                         StackWalkKind walk_kind,
763                         size_t num_frames,
764                         size_t frame_height)
765        : StackVisitor(thread, nullptr, walk_kind, num_frames),
766          frame_height_(frame_height),
767          found_frame_(false),
768          has_more_frames_(false),
769          next_method_(nullptr),
770          next_dex_pc_(0) {
771    }
772
773    bool VisitFrame() OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_) {
774      if (found_frame_) {
775        ArtMethod* method = GetMethod();
776        if (method != nullptr && !method->IsRuntimeMethod()) {
777          has_more_frames_ = true;
778          next_method_ = method;
779          next_dex_pc_ = GetDexPc();
780          return false;  // End stack walk once next method is found.
781        }
782      } else if (GetFrameHeight() == frame_height_) {
783        found_frame_ = true;
784      }
785      return true;
786    }
787
788    size_t frame_height_;
789    bool found_frame_;
790    bool has_more_frames_;
791    ArtMethod* next_method_;
792    uint32_t next_dex_pc_;
793  };
794  HasMoreFramesVisitor visitor(thread_, walk_kind_, GetNumFrames(), GetFrameHeight());
795  visitor.WalkStack(true);
796  *next_method = visitor.next_method_;
797  *next_dex_pc = visitor.next_dex_pc_;
798  return visitor.has_more_frames_;
799}
800
801void StackVisitor::DescribeStack(Thread* thread) {
802  struct DescribeStackVisitor : public StackVisitor {
803    explicit DescribeStackVisitor(Thread* thread_in)
804        : StackVisitor(thread_in, nullptr, StackVisitor::StackWalkKind::kIncludeInlinedFrames) {}
805
806    bool VisitFrame() OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_) {
807      LOG(INFO) << "Frame Id=" << GetFrameId() << " " << DescribeLocation();
808      return true;
809    }
810  };
811  DescribeStackVisitor visitor(thread);
812  visitor.WalkStack(true);
813}
814
815std::string StackVisitor::DescribeLocation() const {
816  std::string result("Visiting method '");
817  ArtMethod* m = GetMethod();
818  if (m == nullptr) {
819    return "upcall";
820  }
821  result += PrettyMethod(m);
822  result += StringPrintf("' at dex PC 0x%04x", GetDexPc());
823  if (!IsShadowFrame()) {
824    result += StringPrintf(" (native PC %p)", reinterpret_cast<void*>(GetCurrentQuickFramePc()));
825  }
826  return result;
827}
828
829static instrumentation::InstrumentationStackFrame& GetInstrumentationStackFrame(Thread* thread,
830                                                                                uint32_t depth) {
831  CHECK_LT(depth, thread->GetInstrumentationStack()->size());
832  return thread->GetInstrumentationStack()->at(depth);
833}
834
835static void AssertPcIsWithinQuickCode(ArtMethod* method, uintptr_t pc)
836    SHARED_REQUIRES(Locks::mutator_lock_) {
837  if (method->IsNative() || method->IsRuntimeMethod() || method->IsProxyMethod()) {
838    return;
839  }
840
841  if (pc == reinterpret_cast<uintptr_t>(GetQuickInstrumentationExitPc())) {
842    return;
843  }
844
845  const void* code = method->GetEntryPointFromQuickCompiledCode();
846  if (code == GetQuickInstrumentationEntryPoint()) {
847    return;
848  }
849
850  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
851  if (class_linker->IsQuickToInterpreterBridge(code) ||
852      class_linker->IsQuickResolutionStub(code)) {
853    return;
854  }
855
856  // If we are the JIT then we may have just compiled the method after the
857  // IsQuickToInterpreterBridge check.
858  jit::Jit* const jit = Runtime::Current()->GetJit();
859  if (jit != nullptr &&
860      jit->GetCodeCache()->ContainsCodePtr(reinterpret_cast<const void*>(code))) {
861    return;
862  }
863
864  uint32_t code_size = reinterpret_cast<const OatQuickMethodHeader*>(
865      EntryPointToCodePointer(code))[-1].code_size_;
866  uintptr_t code_start = reinterpret_cast<uintptr_t>(code);
867  CHECK(code_start <= pc && pc <= (code_start + code_size))
868      << PrettyMethod(method)
869      << " pc=" << std::hex << pc
870      << " code=" << code
871      << " size=" << code_size;
872}
873
874void StackVisitor::SanityCheckFrame() const {
875  if (kIsDebugBuild) {
876    ArtMethod* method = GetMethod();
877    auto* declaring_class = method->GetDeclaringClass();
878    // Runtime methods have null declaring class.
879    if (!method->IsRuntimeMethod()) {
880      CHECK(declaring_class != nullptr);
881      CHECK_EQ(declaring_class->GetClass(), declaring_class->GetClass()->GetClass())
882          << declaring_class;
883    } else {
884      CHECK(declaring_class == nullptr);
885    }
886    Runtime* const runtime = Runtime::Current();
887    LinearAlloc* const linear_alloc = runtime->GetLinearAlloc();
888    if (!linear_alloc->Contains(method)) {
889      // Check class linker linear allocs.
890      mirror::Class* klass = method->GetDeclaringClass();
891      LinearAlloc* const class_linear_alloc = (klass != nullptr)
892          ? ClassLinker::GetAllocatorForClassLoader(klass->GetClassLoader())
893          : linear_alloc;
894      if (!class_linear_alloc->Contains(method)) {
895        // Check image space.
896        bool in_image = false;
897        for (auto& space : runtime->GetHeap()->GetContinuousSpaces()) {
898          if (space->IsImageSpace()) {
899            auto* image_space = space->AsImageSpace();
900            const auto& header = image_space->GetImageHeader();
901            const auto* methods = &header.GetMethodsSection();
902            if (methods->Contains(reinterpret_cast<const uint8_t*>(method) - image_space->Begin())) {
903              in_image = true;
904              break;
905            }
906          }
907        }
908        CHECK(in_image) << PrettyMethod(method) << " not in linear alloc or image";
909      }
910    }
911    if (cur_quick_frame_ != nullptr) {
912      AssertPcIsWithinQuickCode(method, cur_quick_frame_pc_);
913      // Frame sanity.
914      size_t frame_size = GetCurrentQuickFrameInfo().FrameSizeInBytes();
915      CHECK_NE(frame_size, 0u);
916      // A rough guess at an upper size we expect to see for a frame.
917      // 256 registers
918      // 2 words HandleScope overhead
919      // 3+3 register spills
920      // TODO: this seems architecture specific for the case of JNI frames.
921      // TODO: 083-compiler-regressions ManyFloatArgs shows this estimate is wrong.
922      // const size_t kMaxExpectedFrameSize = (256 + 2 + 3 + 3) * sizeof(word);
923      const size_t kMaxExpectedFrameSize = 2 * KB;
924      CHECK_LE(frame_size, kMaxExpectedFrameSize) << PrettyMethod(method);
925      size_t return_pc_offset = GetCurrentQuickFrameInfo().GetReturnPcOffset();
926      CHECK_LT(return_pc_offset, frame_size);
927    }
928  }
929}
930
931// Counts the number of references in the parameter list of the corresponding method.
932// Note: Thus does _not_ include "this" for non-static methods.
933static uint32_t GetNumberOfReferenceArgsWithoutReceiver(ArtMethod* method)
934    SHARED_REQUIRES(Locks::mutator_lock_) {
935  uint32_t shorty_len;
936  const char* shorty = method->GetShorty(&shorty_len);
937  uint32_t refs = 0;
938  for (uint32_t i = 1; i < shorty_len ; ++i) {
939    if (shorty[i] == 'L') {
940      refs++;
941    }
942  }
943  return refs;
944}
945
946QuickMethodFrameInfo StackVisitor::GetCurrentQuickFrameInfo() const {
947  if (cur_oat_quick_method_header_ != nullptr) {
948    return cur_oat_quick_method_header_->GetFrameInfo();
949  }
950
951  ArtMethod* method = GetMethod();
952  Runtime* runtime = Runtime::Current();
953
954  if (method->IsAbstract()) {
955    return runtime->GetCalleeSaveMethodFrameInfo(Runtime::kRefsAndArgs);
956  }
957
958  // This goes before IsProxyMethod since runtime methods have a null declaring class.
959  if (method->IsRuntimeMethod()) {
960    return runtime->GetRuntimeMethodFrameInfo(method);
961  }
962
963  // For Proxy method we add special handling for the direct method case  (there is only one
964  // direct method - constructor). Direct method is cloned from original
965  // java.lang.reflect.Proxy class together with code and as a result it is executed as usual
966  // quick compiled method without any stubs. So the frame info should be returned as it is a
967  // quick method not a stub. However, if instrumentation stubs are installed, the
968  // instrumentation->GetQuickCodeFor() returns the artQuickProxyInvokeHandler instead of an
969  // oat code pointer, thus we have to add a special case here.
970  if (method->IsProxyMethod()) {
971    if (method->IsDirect()) {
972      CHECK(method->IsConstructor());
973      const void* code_pointer =
974          EntryPointToCodePointer(method->GetEntryPointFromQuickCompiledCode());
975      return reinterpret_cast<const OatQuickMethodHeader*>(code_pointer)[-1].frame_info_;
976    } else {
977      return runtime->GetCalleeSaveMethodFrameInfo(Runtime::kRefsAndArgs);
978    }
979  }
980
981  ClassLinker* class_linker = runtime->GetClassLinker();
982  DCHECK(method->IsNative());
983  const void* entry_point = runtime->GetInstrumentation()->GetQuickCodeFor(method, sizeof(void*));
984  DCHECK(class_linker->IsQuickGenericJniStub(entry_point)) << PrettyMethod(method);
985  // Generic JNI frame.
986  uint32_t handle_refs = GetNumberOfReferenceArgsWithoutReceiver(method) + 1;
987  size_t scope_size = HandleScope::SizeOf(handle_refs);
988  QuickMethodFrameInfo callee_info = runtime->GetCalleeSaveMethodFrameInfo(Runtime::kRefsAndArgs);
989
990  // Callee saves + handle scope + method ref + alignment
991  // Note: -sizeof(void*) since callee-save frame stores a whole method pointer.
992  size_t frame_size = RoundUp(
993      callee_info.FrameSizeInBytes() - sizeof(void*) + sizeof(ArtMethod*) + scope_size,
994      kStackAlignment);
995  return QuickMethodFrameInfo(frame_size, callee_info.CoreSpillMask(), callee_info.FpSpillMask());
996}
997
998void StackVisitor::WalkStack(bool include_transitions) {
999  DCHECK(thread_ == Thread::Current() || thread_->IsSuspended());
1000  CHECK_EQ(cur_depth_, 0U);
1001  bool exit_stubs_installed = Runtime::Current()->GetInstrumentation()->AreExitStubsInstalled();
1002  uint32_t instrumentation_stack_depth = 0;
1003  size_t inlined_frames_count = 0;
1004
1005  for (const ManagedStack* current_fragment = thread_->GetManagedStack();
1006       current_fragment != nullptr; current_fragment = current_fragment->GetLink()) {
1007    cur_shadow_frame_ = current_fragment->GetTopShadowFrame();
1008    cur_quick_frame_ = current_fragment->GetTopQuickFrame();
1009    cur_quick_frame_pc_ = 0;
1010    cur_oat_quick_method_header_ = nullptr;
1011
1012    if (cur_quick_frame_ != nullptr) {  // Handle quick stack frames.
1013      // Can't be both a shadow and a quick fragment.
1014      DCHECK(current_fragment->GetTopShadowFrame() == nullptr);
1015      ArtMethod* method = *cur_quick_frame_;
1016      while (method != nullptr) {
1017        cur_oat_quick_method_header_ = method->GetOatQuickMethodHeader(cur_quick_frame_pc_);
1018        SanityCheckFrame();
1019
1020        if ((walk_kind_ == StackWalkKind::kIncludeInlinedFrames)
1021            && (cur_oat_quick_method_header_ != nullptr)
1022            && cur_oat_quick_method_header_->IsOptimized()) {
1023          CodeInfo code_info = cur_oat_quick_method_header_->GetOptimizedCodeInfo();
1024          StackMapEncoding encoding = code_info.ExtractEncoding();
1025          uint32_t native_pc_offset =
1026              cur_oat_quick_method_header_->NativeQuickPcOffset(cur_quick_frame_pc_);
1027          StackMap stack_map = code_info.GetStackMapForNativePcOffset(native_pc_offset, encoding);
1028          if (stack_map.IsValid() && stack_map.HasInlineInfo(encoding)) {
1029            InlineInfo inline_info = code_info.GetInlineInfoOf(stack_map, encoding);
1030            DCHECK_EQ(current_inlining_depth_, 0u);
1031            for (current_inlining_depth_ = inline_info.GetDepth();
1032                 current_inlining_depth_ != 0;
1033                 --current_inlining_depth_) {
1034              bool should_continue = VisitFrame();
1035              if (UNLIKELY(!should_continue)) {
1036                return;
1037              }
1038              cur_depth_++;
1039              inlined_frames_count++;
1040            }
1041          }
1042        }
1043
1044        bool should_continue = VisitFrame();
1045        if (UNLIKELY(!should_continue)) {
1046          return;
1047        }
1048
1049        QuickMethodFrameInfo frame_info = GetCurrentQuickFrameInfo();
1050        if (context_ != nullptr) {
1051          context_->FillCalleeSaves(reinterpret_cast<uint8_t*>(cur_quick_frame_), frame_info);
1052        }
1053        // Compute PC for next stack frame from return PC.
1054        size_t frame_size = frame_info.FrameSizeInBytes();
1055        size_t return_pc_offset = frame_size - sizeof(void*);
1056        uint8_t* return_pc_addr = reinterpret_cast<uint8_t*>(cur_quick_frame_) + return_pc_offset;
1057        uintptr_t return_pc = *reinterpret_cast<uintptr_t*>(return_pc_addr);
1058
1059        if (UNLIKELY(exit_stubs_installed)) {
1060          // While profiling, the return pc is restored from the side stack, except when walking
1061          // the stack for an exception where the side stack will be unwound in VisitFrame.
1062          if (reinterpret_cast<uintptr_t>(GetQuickInstrumentationExitPc()) == return_pc) {
1063            const instrumentation::InstrumentationStackFrame& instrumentation_frame =
1064                GetInstrumentationStackFrame(thread_, instrumentation_stack_depth);
1065            instrumentation_stack_depth++;
1066            if (GetMethod() == Runtime::Current()->GetCalleeSaveMethod(Runtime::kSaveAll)) {
1067              // Skip runtime save all callee frames which are used to deliver exceptions.
1068            } else if (instrumentation_frame.interpreter_entry_) {
1069              ArtMethod* callee = Runtime::Current()->GetCalleeSaveMethod(Runtime::kRefsAndArgs);
1070              CHECK_EQ(GetMethod(), callee) << "Expected: " << PrettyMethod(callee) << " Found: "
1071                                            << PrettyMethod(GetMethod());
1072            } else {
1073              CHECK_EQ(instrumentation_frame.method_, GetMethod())
1074                  << "Expected: " << PrettyMethod(instrumentation_frame.method_)
1075                  << " Found: " << PrettyMethod(GetMethod());
1076            }
1077            if (num_frames_ != 0) {
1078              // Check agreement of frame Ids only if num_frames_ is computed to avoid infinite
1079              // recursion.
1080              size_t frame_id = instrumentation::Instrumentation::ComputeFrameId(
1081                  thread_,
1082                  cur_depth_,
1083                  inlined_frames_count);
1084              CHECK_EQ(instrumentation_frame.frame_id_, frame_id);
1085            }
1086            return_pc = instrumentation_frame.return_pc_;
1087          }
1088        }
1089
1090        cur_quick_frame_pc_ = return_pc;
1091        uint8_t* next_frame = reinterpret_cast<uint8_t*>(cur_quick_frame_) + frame_size;
1092        cur_quick_frame_ = reinterpret_cast<ArtMethod**>(next_frame);
1093
1094        if (kDebugStackWalk) {
1095          LOG(INFO) << PrettyMethod(method) << "@" << method << " size=" << frame_size
1096              << std::boolalpha
1097              << " optimized=" << (cur_oat_quick_method_header_ != nullptr &&
1098                                   cur_oat_quick_method_header_->IsOptimized())
1099              << " native=" << method->IsNative()
1100              << std::noboolalpha
1101              << " entrypoints=" << method->GetEntryPointFromQuickCompiledCode()
1102              << "," << method->GetEntryPointFromJni()
1103              << " next=" << *cur_quick_frame_;
1104        }
1105
1106        cur_depth_++;
1107        method = *cur_quick_frame_;
1108      }
1109    } else if (cur_shadow_frame_ != nullptr) {
1110      do {
1111        SanityCheckFrame();
1112        bool should_continue = VisitFrame();
1113        if (UNLIKELY(!should_continue)) {
1114          return;
1115        }
1116        cur_depth_++;
1117        cur_shadow_frame_ = cur_shadow_frame_->GetLink();
1118      } while (cur_shadow_frame_ != nullptr);
1119    }
1120    if (include_transitions) {
1121      bool should_continue = VisitFrame();
1122      if (!should_continue) {
1123        return;
1124      }
1125    }
1126    cur_depth_++;
1127  }
1128  if (num_frames_ != 0) {
1129    CHECK_EQ(cur_depth_, num_frames_);
1130  }
1131}
1132
1133void JavaFrameRootInfo::Describe(std::ostream& os) const {
1134  const StackVisitor* visitor = stack_visitor_;
1135  CHECK(visitor != nullptr);
1136  os << "Type=" << GetType() << " thread_id=" << GetThreadId() << " location=" <<
1137      visitor->DescribeLocation() << " vreg=" << vreg_;
1138}
1139
1140int StackVisitor::GetVRegOffsetFromQuickCode(const DexFile::CodeItem* code_item,
1141                                             uint32_t core_spills, uint32_t fp_spills,
1142                                             size_t frame_size, int reg, InstructionSet isa) {
1143  size_t pointer_size = InstructionSetPointerSize(isa);
1144  if (kIsDebugBuild) {
1145    auto* runtime = Runtime::Current();
1146    if (runtime != nullptr) {
1147      CHECK_EQ(runtime->GetClassLinker()->GetImagePointerSize(), pointer_size);
1148    }
1149  }
1150  DCHECK_ALIGNED(frame_size, kStackAlignment);
1151  DCHECK_NE(reg, -1);
1152  int spill_size = POPCOUNT(core_spills) * GetBytesPerGprSpillLocation(isa)
1153      + POPCOUNT(fp_spills) * GetBytesPerFprSpillLocation(isa)
1154      + sizeof(uint32_t);  // Filler.
1155  int num_regs = code_item->registers_size_ - code_item->ins_size_;
1156  int temp_threshold = code_item->registers_size_;
1157  const int max_num_special_temps = 1;
1158  if (reg == temp_threshold) {
1159    // The current method pointer corresponds to special location on stack.
1160    return 0;
1161  } else if (reg >= temp_threshold + max_num_special_temps) {
1162    /*
1163     * Special temporaries may have custom locations and the logic above deals with that.
1164     * However, non-special temporaries are placed relative to the outs.
1165     */
1166    int temps_start = code_item->outs_size_ * sizeof(uint32_t) + pointer_size /* art method */;
1167    int relative_offset = (reg - (temp_threshold + max_num_special_temps)) * sizeof(uint32_t);
1168    return temps_start + relative_offset;
1169  }  else if (reg < num_regs) {
1170    int locals_start = frame_size - spill_size - num_regs * sizeof(uint32_t);
1171    return locals_start + (reg * sizeof(uint32_t));
1172  } else {
1173    // Handle ins.
1174    return frame_size + ((reg - num_regs) * sizeof(uint32_t)) + pointer_size /* art method */;
1175  }
1176}
1177
1178void LockCountData::AddMonitorInternal(Thread* self, mirror::Object* obj) {
1179  if (obj == nullptr) {
1180    return;
1181  }
1182
1183  // If there's an error during enter, we won't have locked the monitor. So check there's no
1184  // exception.
1185  if (self->IsExceptionPending()) {
1186    return;
1187  }
1188
1189  if (monitors_ == nullptr) {
1190    monitors_.reset(new std::vector<mirror::Object*>());
1191  }
1192  monitors_->push_back(obj);
1193}
1194
1195void LockCountData::RemoveMonitorInternal(Thread* self, const mirror::Object* obj) {
1196  if (obj == nullptr) {
1197    return;
1198  }
1199  bool found_object = false;
1200  if (monitors_ != nullptr) {
1201    // We need to remove one pointer to ref, as duplicates are used for counting recursive locks.
1202    // We arbitrarily choose the first one.
1203    auto it = std::find(monitors_->begin(), monitors_->end(), obj);
1204    if (it != monitors_->end()) {
1205      monitors_->erase(it);
1206      found_object = true;
1207    }
1208  }
1209  if (!found_object) {
1210    // The object wasn't found. Time for an IllegalMonitorStateException.
1211    // The order here isn't fully clear. Assume that any other pending exception is swallowed.
1212    // TODO: Maybe make already pending exception a suppressed exception.
1213    self->ClearException();
1214    self->ThrowNewExceptionF("Ljava/lang/IllegalMonitorStateException;",
1215                             "did not lock monitor on object of type '%s' before unlocking",
1216                             PrettyTypeOf(const_cast<mirror::Object*>(obj)).c_str());
1217  }
1218}
1219
1220// Helper to unlock a monitor. Must be NO_THREAD_SAFETY_ANALYSIS, as we can't statically show
1221// that the object was locked.
1222void MonitorExitHelper(Thread* self, mirror::Object* obj) NO_THREAD_SAFETY_ANALYSIS {
1223  DCHECK(self != nullptr);
1224  DCHECK(obj != nullptr);
1225  obj->MonitorExit(self);
1226}
1227
1228bool LockCountData::CheckAllMonitorsReleasedInternal(Thread* self) {
1229  DCHECK(self != nullptr);
1230  if (monitors_ != nullptr) {
1231    if (!monitors_->empty()) {
1232      // There may be an exception pending, if the method is terminating abruptly. Clear it.
1233      // TODO: Should we add this as a suppressed exception?
1234      self->ClearException();
1235
1236      // OK, there are monitors that are still locked. To enforce structured locking (and avoid
1237      // deadlocks) we unlock all of them before we raise the IllegalMonitorState exception.
1238      for (mirror::Object* obj : *monitors_) {
1239        MonitorExitHelper(self, obj);
1240        // If this raised an exception, ignore. TODO: Should we add this as suppressed
1241        // exceptions?
1242        if (self->IsExceptionPending()) {
1243          self->ClearException();
1244        }
1245      }
1246      // Raise an exception, just give the first object as the sample.
1247      mirror::Object* first = (*monitors_)[0];
1248      self->ThrowNewExceptionF("Ljava/lang/IllegalMonitorStateException;",
1249                               "did not unlock monitor on object of type '%s'",
1250                               PrettyTypeOf(first).c_str());
1251
1252      // To make sure this path is not triggered again, clean out the monitors.
1253      monitors_->clear();
1254
1255      return false;
1256    }
1257  }
1258  return true;
1259}
1260
1261}  // namespace art
1262