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 "base/hex_dump.h"
21 #include "mirror/art_method-inl.h"
22 #include "mirror/class-inl.h"
23 #include "mirror/object.h"
24 #include "mirror/object-inl.h"
25 #include "mirror/object_array-inl.h"
26 #include "quick/quick_method_frame_info.h"
27 #include "runtime.h"
28 #include "thread.h"
29 #include "thread_list.h"
30 #include "throw_location.h"
31 #include "verify_object-inl.h"
32 #include "vmap_table.h"
33
34 namespace art {
35
GetThisObject() const36 mirror::Object* ShadowFrame::GetThisObject() const {
37 mirror::ArtMethod* m = GetMethod();
38 if (m->IsStatic()) {
39 return NULL;
40 } else if (m->IsNative()) {
41 return GetVRegReference(0);
42 } else {
43 const DexFile::CodeItem* code_item = m->GetCodeItem();
44 CHECK(code_item != NULL) << PrettyMethod(m);
45 uint16_t reg = code_item->registers_size_ - code_item->ins_size_;
46 return GetVRegReference(reg);
47 }
48 }
49
GetThisObject(uint16_t num_ins) const50 mirror::Object* ShadowFrame::GetThisObject(uint16_t num_ins) const {
51 mirror::ArtMethod* m = GetMethod();
52 if (m->IsStatic()) {
53 return NULL;
54 } else {
55 return GetVRegReference(NumberOfVRegs() - num_ins);
56 }
57 }
58
GetCurrentLocationForThrow() const59 ThrowLocation ShadowFrame::GetCurrentLocationForThrow() const {
60 return ThrowLocation(GetThisObject(), GetMethod(), GetDexPC());
61 }
62
NumJniShadowFrameReferences() const63 size_t ManagedStack::NumJniShadowFrameReferences() const {
64 size_t count = 0;
65 for (const ManagedStack* current_fragment = this; current_fragment != NULL;
66 current_fragment = current_fragment->GetLink()) {
67 for (ShadowFrame* current_frame = current_fragment->top_shadow_frame_; current_frame != NULL;
68 current_frame = current_frame->GetLink()) {
69 if (current_frame->GetMethod()->IsNative()) {
70 // The JNI ShadowFrame only contains references. (For indirect reference.)
71 count += current_frame->NumberOfVRegs();
72 }
73 }
74 }
75 return count;
76 }
77
ShadowFramesContain(StackReference<mirror::Object> * shadow_frame_entry) const78 bool ManagedStack::ShadowFramesContain(StackReference<mirror::Object>* shadow_frame_entry) const {
79 for (const ManagedStack* current_fragment = this; current_fragment != NULL;
80 current_fragment = current_fragment->GetLink()) {
81 for (ShadowFrame* current_frame = current_fragment->top_shadow_frame_; current_frame != NULL;
82 current_frame = current_frame->GetLink()) {
83 if (current_frame->Contains(shadow_frame_entry)) {
84 return true;
85 }
86 }
87 }
88 return false;
89 }
90
StackVisitor(Thread * thread,Context * context)91 StackVisitor::StackVisitor(Thread* thread, Context* context)
92 : thread_(thread), cur_shadow_frame_(NULL),
93 cur_quick_frame_(NULL), cur_quick_frame_pc_(0), num_frames_(0), cur_depth_(0),
94 context_(context) {
95 DCHECK(thread == Thread::Current() || thread->IsSuspended()) << *thread;
96 }
97
StackVisitor(Thread * thread,Context * context,size_t num_frames)98 StackVisitor::StackVisitor(Thread* thread, Context* context, size_t num_frames)
99 : thread_(thread), cur_shadow_frame_(NULL),
100 cur_quick_frame_(NULL), cur_quick_frame_pc_(0), num_frames_(num_frames), cur_depth_(0),
101 context_(context) {
102 DCHECK(thread == Thread::Current() || thread->IsSuspended()) << *thread;
103 }
104
GetDexPc(bool abort_on_failure) const105 uint32_t StackVisitor::GetDexPc(bool abort_on_failure) const {
106 if (cur_shadow_frame_ != NULL) {
107 return cur_shadow_frame_->GetDexPC();
108 } else if (cur_quick_frame_ != NULL) {
109 return GetMethod()->ToDexPc(cur_quick_frame_pc_, abort_on_failure);
110 } else {
111 return 0;
112 }
113 }
114
GetThisObject() const115 mirror::Object* StackVisitor::GetThisObject() const {
116 mirror::ArtMethod* m = GetMethod();
117 if (m->IsStatic()) {
118 return NULL;
119 } else if (m->IsNative()) {
120 if (cur_quick_frame_ != NULL) {
121 HandleScope* hs = reinterpret_cast<HandleScope*>(
122 reinterpret_cast<char*>(cur_quick_frame_) + m->GetHandleScopeOffsetInBytes());
123 return hs->GetReference(0);
124 } else {
125 return cur_shadow_frame_->GetVRegReference(0);
126 }
127 } else {
128 const DexFile::CodeItem* code_item = m->GetCodeItem();
129 if (code_item == NULL) {
130 UNIMPLEMENTED(ERROR) << "Failed to determine this object of abstract or proxy method: "
131 << PrettyMethod(m);
132 return nullptr;
133 } else {
134 uint16_t reg = code_item->registers_size_ - code_item->ins_size_;
135 return reinterpret_cast<mirror::Object*>(GetVReg(m, reg, kReferenceVReg));
136 }
137 }
138 }
139
GetNativePcOffset() const140 size_t StackVisitor::GetNativePcOffset() const {
141 DCHECK(!IsShadowFrame());
142 return GetMethod()->NativePcOffset(cur_quick_frame_pc_);
143 }
144
GetVReg(mirror::ArtMethod * m,uint16_t vreg,VRegKind kind,uint32_t * val) const145 bool StackVisitor::GetVReg(mirror::ArtMethod* m, uint16_t vreg, VRegKind kind,
146 uint32_t* val) const {
147 if (cur_quick_frame_ != nullptr) {
148 DCHECK(context_ != nullptr); // You can't reliably read registers without a context.
149 DCHECK(m == GetMethod());
150 const void* code_pointer = m->GetQuickOatCodePointer();
151 DCHECK(code_pointer != nullptr);
152 const VmapTable vmap_table(m->GetVmapTable(code_pointer));
153 QuickMethodFrameInfo frame_info = m->GetQuickFrameInfo(code_pointer);
154 uint32_t vmap_offset;
155 // TODO: IsInContext stops before spotting floating point registers.
156 if (vmap_table.IsInContext(vreg, kind, &vmap_offset)) {
157 bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg);
158 uint32_t spill_mask = is_float ? frame_info.FpSpillMask() : frame_info.CoreSpillMask();
159 uint32_t reg = vmap_table.ComputeRegister(spill_mask, vmap_offset, kind);
160 uintptr_t ptr_val;
161 bool success = is_float ? GetFPR(reg, &ptr_val) : GetGPR(reg, &ptr_val);
162 if (!success) {
163 return false;
164 }
165 bool target64 = Is64BitInstructionSet(kRuntimeISA);
166 if (target64) {
167 bool wide_lo = (kind == kLongLoVReg) || (kind == kDoubleLoVReg);
168 bool wide_hi = (kind == kLongHiVReg) || (kind == kDoubleHiVReg);
169 int64_t value_long = static_cast<int64_t>(ptr_val);
170 if (wide_lo) {
171 ptr_val = static_cast<uintptr_t>(value_long & 0xFFFFFFFF);
172 } else if (wide_hi) {
173 ptr_val = static_cast<uintptr_t>(value_long >> 32);
174 }
175 }
176 *val = ptr_val;
177 return true;
178 } else {
179 const DexFile::CodeItem* code_item = m->GetCodeItem();
180 DCHECK(code_item != nullptr) << PrettyMethod(m); // Can't be NULL or how would we compile
181 // its instructions?
182 *val = *GetVRegAddr(cur_quick_frame_, code_item, frame_info.CoreSpillMask(),
183 frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), vreg);
184 return true;
185 }
186 } else {
187 *val = cur_shadow_frame_->GetVReg(vreg);
188 return true;
189 }
190 }
191
GetVRegPair(mirror::ArtMethod * m,uint16_t vreg,VRegKind kind_lo,VRegKind kind_hi,uint64_t * val) const192 bool StackVisitor::GetVRegPair(mirror::ArtMethod* m, uint16_t vreg, VRegKind kind_lo,
193 VRegKind kind_hi, uint64_t* val) const {
194 if (kind_lo == kLongLoVReg) {
195 DCHECK_EQ(kind_hi, kLongHiVReg);
196 } else if (kind_lo == kDoubleLoVReg) {
197 DCHECK_EQ(kind_hi, kDoubleHiVReg);
198 } else {
199 LOG(FATAL) << "Expected long or double: kind_lo=" << kind_lo << ", kind_hi=" << kind_hi;
200 }
201 if (cur_quick_frame_ != nullptr) {
202 DCHECK(context_ != nullptr); // You can't reliably read registers without a context.
203 DCHECK(m == GetMethod());
204 const void* code_pointer = m->GetQuickOatCodePointer();
205 DCHECK(code_pointer != nullptr);
206 const VmapTable vmap_table(m->GetVmapTable(code_pointer));
207 QuickMethodFrameInfo frame_info = m->GetQuickFrameInfo(code_pointer);
208 uint32_t vmap_offset_lo, vmap_offset_hi;
209 // TODO: IsInContext stops before spotting floating point registers.
210 if (vmap_table.IsInContext(vreg, kind_lo, &vmap_offset_lo) &&
211 vmap_table.IsInContext(vreg + 1, kind_hi, &vmap_offset_hi)) {
212 bool is_float = (kind_lo == kDoubleLoVReg);
213 uint32_t spill_mask = is_float ? frame_info.FpSpillMask() : frame_info.CoreSpillMask();
214 uint32_t reg_lo = vmap_table.ComputeRegister(spill_mask, vmap_offset_lo, kind_lo);
215 uint32_t reg_hi = vmap_table.ComputeRegister(spill_mask, vmap_offset_hi, kind_hi);
216 uintptr_t ptr_val_lo, ptr_val_hi;
217 bool success = is_float ? GetFPR(reg_lo, &ptr_val_lo) : GetGPR(reg_lo, &ptr_val_lo);
218 success &= is_float ? GetFPR(reg_hi, &ptr_val_hi) : GetGPR(reg_hi, &ptr_val_hi);
219 if (!success) {
220 return false;
221 }
222 bool target64 = Is64BitInstructionSet(kRuntimeISA);
223 if (target64) {
224 int64_t value_long_lo = static_cast<int64_t>(ptr_val_lo);
225 int64_t value_long_hi = static_cast<int64_t>(ptr_val_hi);
226 ptr_val_lo = static_cast<uintptr_t>(value_long_lo & 0xFFFFFFFF);
227 ptr_val_hi = static_cast<uintptr_t>(value_long_hi >> 32);
228 }
229 *val = (static_cast<uint64_t>(ptr_val_hi) << 32) | static_cast<uint32_t>(ptr_val_lo);
230 return true;
231 } else {
232 const DexFile::CodeItem* code_item = m->GetCodeItem();
233 DCHECK(code_item != nullptr) << PrettyMethod(m); // Can't be NULL or how would we compile
234 // its instructions?
235 uint32_t* addr = GetVRegAddr(cur_quick_frame_, code_item, frame_info.CoreSpillMask(),
236 frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), vreg);
237 *val = *reinterpret_cast<uint64_t*>(addr);
238 return true;
239 }
240 } else {
241 *val = cur_shadow_frame_->GetVRegLong(vreg);
242 return true;
243 }
244 }
245
SetVReg(mirror::ArtMethod * m,uint16_t vreg,uint32_t new_value,VRegKind kind)246 bool StackVisitor::SetVReg(mirror::ArtMethod* m, uint16_t vreg, uint32_t new_value,
247 VRegKind kind) {
248 if (cur_quick_frame_ != nullptr) {
249 DCHECK(context_ != nullptr); // You can't reliably write registers without a context.
250 DCHECK(m == GetMethod());
251 const void* code_pointer = m->GetQuickOatCodePointer();
252 DCHECK(code_pointer != nullptr);
253 const VmapTable vmap_table(m->GetVmapTable(code_pointer));
254 QuickMethodFrameInfo frame_info = m->GetQuickFrameInfo(code_pointer);
255 uint32_t vmap_offset;
256 // TODO: IsInContext stops before spotting floating point registers.
257 if (vmap_table.IsInContext(vreg, kind, &vmap_offset)) {
258 bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg);
259 uint32_t spill_mask = is_float ? frame_info.FpSpillMask() : frame_info.CoreSpillMask();
260 const uint32_t reg = vmap_table.ComputeRegister(spill_mask, vmap_offset, kind);
261 bool target64 = Is64BitInstructionSet(kRuntimeISA);
262 // Deal with 32 or 64-bit wide registers in a way that builds on all targets.
263 if (target64) {
264 bool wide_lo = (kind == kLongLoVReg) || (kind == kDoubleLoVReg);
265 bool wide_hi = (kind == kLongHiVReg) || (kind == kDoubleHiVReg);
266 if (wide_lo || wide_hi) {
267 uintptr_t old_reg_val;
268 bool success = is_float ? GetFPR(reg, &old_reg_val) : GetGPR(reg, &old_reg_val);
269 if (!success) {
270 return false;
271 }
272 uint64_t new_vreg_portion = static_cast<uint64_t>(new_value);
273 uint64_t old_reg_val_as_wide = static_cast<uint64_t>(old_reg_val);
274 uint64_t mask = 0xffffffff;
275 if (wide_lo) {
276 mask = mask << 32;
277 } else {
278 new_vreg_portion = new_vreg_portion << 32;
279 }
280 new_value = static_cast<uintptr_t>((old_reg_val_as_wide & mask) | new_vreg_portion);
281 }
282 }
283 if (is_float) {
284 return SetFPR(reg, new_value);
285 } else {
286 return SetGPR(reg, new_value);
287 }
288 } else {
289 const DexFile::CodeItem* code_item = m->GetCodeItem();
290 DCHECK(code_item != nullptr) << PrettyMethod(m); // Can't be NULL or how would we compile
291 // its instructions?
292 uint32_t* addr = GetVRegAddr(cur_quick_frame_, code_item, frame_info.CoreSpillMask(),
293 frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), vreg);
294 *addr = new_value;
295 return true;
296 }
297 } else {
298 cur_shadow_frame_->SetVReg(vreg, new_value);
299 return true;
300 }
301 }
302
SetVRegPair(mirror::ArtMethod * m,uint16_t vreg,uint64_t new_value,VRegKind kind_lo,VRegKind kind_hi)303 bool StackVisitor::SetVRegPair(mirror::ArtMethod* m, uint16_t vreg, uint64_t new_value,
304 VRegKind kind_lo, VRegKind kind_hi) {
305 if (kind_lo == kLongLoVReg) {
306 DCHECK_EQ(kind_hi, kLongHiVReg);
307 } else if (kind_lo == kDoubleLoVReg) {
308 DCHECK_EQ(kind_hi, kDoubleHiVReg);
309 } else {
310 LOG(FATAL) << "Expected long or double: kind_lo=" << kind_lo << ", kind_hi=" << kind_hi;
311 }
312 if (cur_quick_frame_ != nullptr) {
313 DCHECK(context_ != nullptr); // You can't reliably write registers without a context.
314 DCHECK(m == GetMethod());
315 const void* code_pointer = m->GetQuickOatCodePointer();
316 DCHECK(code_pointer != nullptr);
317 const VmapTable vmap_table(m->GetVmapTable(code_pointer));
318 QuickMethodFrameInfo frame_info = m->GetQuickFrameInfo(code_pointer);
319 uint32_t vmap_offset_lo, vmap_offset_hi;
320 // TODO: IsInContext stops before spotting floating point registers.
321 if (vmap_table.IsInContext(vreg, kind_lo, &vmap_offset_lo) &&
322 vmap_table.IsInContext(vreg + 1, kind_hi, &vmap_offset_hi)) {
323 bool is_float = (kind_lo == kDoubleLoVReg);
324 uint32_t spill_mask = is_float ? frame_info.FpSpillMask() : frame_info.CoreSpillMask();
325 uint32_t reg_lo = vmap_table.ComputeRegister(spill_mask, vmap_offset_lo, kind_lo);
326 uint32_t reg_hi = vmap_table.ComputeRegister(spill_mask, vmap_offset_hi, kind_hi);
327 uintptr_t new_value_lo = static_cast<uintptr_t>(new_value & 0xFFFFFFFF);
328 uintptr_t new_value_hi = static_cast<uintptr_t>(new_value >> 32);
329 bool target64 = Is64BitInstructionSet(kRuntimeISA);
330 // Deal with 32 or 64-bit wide registers in a way that builds on all targets.
331 if (target64) {
332 uintptr_t old_reg_val_lo, old_reg_val_hi;
333 bool success = is_float ? GetFPR(reg_lo, &old_reg_val_lo) : GetGPR(reg_lo, &old_reg_val_lo);
334 success &= is_float ? GetFPR(reg_hi, &old_reg_val_hi) : GetGPR(reg_hi, &old_reg_val_hi);
335 if (!success) {
336 return false;
337 }
338 uint64_t new_vreg_portion_lo = static_cast<uint64_t>(new_value_lo);
339 uint64_t new_vreg_portion_hi = static_cast<uint64_t>(new_value_hi) << 32;
340 uint64_t old_reg_val_lo_as_wide = static_cast<uint64_t>(old_reg_val_lo);
341 uint64_t old_reg_val_hi_as_wide = static_cast<uint64_t>(old_reg_val_hi);
342 uint64_t mask_lo = static_cast<uint64_t>(0xffffffff) << 32;
343 uint64_t mask_hi = 0xffffffff;
344 new_value_lo = static_cast<uintptr_t>((old_reg_val_lo_as_wide & mask_lo) | new_vreg_portion_lo);
345 new_value_hi = static_cast<uintptr_t>((old_reg_val_hi_as_wide & mask_hi) | new_vreg_portion_hi);
346 }
347 bool success = is_float ? SetFPR(reg_lo, new_value_lo) : SetGPR(reg_lo, new_value_lo);
348 success &= is_float ? SetFPR(reg_hi, new_value_hi) : SetGPR(reg_hi, new_value_hi);
349 return success;
350 } else {
351 const DexFile::CodeItem* code_item = m->GetCodeItem();
352 DCHECK(code_item != nullptr) << PrettyMethod(m); // Can't be NULL or how would we compile
353 // its instructions?
354 uint32_t* addr = GetVRegAddr(cur_quick_frame_, code_item, frame_info.CoreSpillMask(),
355 frame_info.FpSpillMask(), frame_info.FrameSizeInBytes(), vreg);
356 *reinterpret_cast<uint64_t*>(addr) = new_value;
357 return true;
358 }
359 } else {
360 cur_shadow_frame_->SetVRegLong(vreg, new_value);
361 return true;
362 }
363 }
364
GetGPRAddress(uint32_t reg) const365 uintptr_t* StackVisitor::GetGPRAddress(uint32_t reg) const {
366 DCHECK(cur_quick_frame_ != NULL) << "This is a quick frame routine";
367 return context_->GetGPRAddress(reg);
368 }
369
GetGPR(uint32_t reg,uintptr_t * val) const370 bool StackVisitor::GetGPR(uint32_t reg, uintptr_t* val) const {
371 DCHECK(cur_quick_frame_ != NULL) << "This is a quick frame routine";
372 return context_->GetGPR(reg, val);
373 }
374
SetGPR(uint32_t reg,uintptr_t value)375 bool StackVisitor::SetGPR(uint32_t reg, uintptr_t value) {
376 DCHECK(cur_quick_frame_ != NULL) << "This is a quick frame routine";
377 return context_->SetGPR(reg, value);
378 }
379
GetFPR(uint32_t reg,uintptr_t * val) const380 bool StackVisitor::GetFPR(uint32_t reg, uintptr_t* val) const {
381 DCHECK(cur_quick_frame_ != NULL) << "This is a quick frame routine";
382 return context_->GetFPR(reg, val);
383 }
384
SetFPR(uint32_t reg,uintptr_t value)385 bool StackVisitor::SetFPR(uint32_t reg, uintptr_t value) {
386 DCHECK(cur_quick_frame_ != NULL) << "This is a quick frame routine";
387 return context_->SetFPR(reg, value);
388 }
389
GetReturnPc() const390 uintptr_t StackVisitor::GetReturnPc() const {
391 byte* sp = reinterpret_cast<byte*>(GetCurrentQuickFrame());
392 DCHECK(sp != NULL);
393 byte* pc_addr = sp + GetMethod()->GetReturnPcOffsetInBytes();
394 return *reinterpret_cast<uintptr_t*>(pc_addr);
395 }
396
SetReturnPc(uintptr_t new_ret_pc)397 void StackVisitor::SetReturnPc(uintptr_t new_ret_pc) {
398 byte* sp = reinterpret_cast<byte*>(GetCurrentQuickFrame());
399 CHECK(sp != NULL);
400 byte* pc_addr = sp + GetMethod()->GetReturnPcOffsetInBytes();
401 *reinterpret_cast<uintptr_t*>(pc_addr) = new_ret_pc;
402 }
403
ComputeNumFrames(Thread * thread)404 size_t StackVisitor::ComputeNumFrames(Thread* thread) {
405 struct NumFramesVisitor : public StackVisitor {
406 explicit NumFramesVisitor(Thread* thread)
407 : StackVisitor(thread, NULL), frames(0) {}
408
409 bool VisitFrame() OVERRIDE {
410 frames++;
411 return true;
412 }
413
414 size_t frames;
415 };
416 NumFramesVisitor visitor(thread);
417 visitor.WalkStack(true);
418 return visitor.frames;
419 }
420
GetNextMethodAndDexPc(mirror::ArtMethod ** next_method,uint32_t * next_dex_pc)421 bool StackVisitor::GetNextMethodAndDexPc(mirror::ArtMethod** next_method, uint32_t* next_dex_pc) {
422 struct HasMoreFramesVisitor : public StackVisitor {
423 explicit HasMoreFramesVisitor(Thread* thread, size_t num_frames, size_t frame_height)
424 : StackVisitor(thread, nullptr, num_frames), frame_height_(frame_height),
425 found_frame_(false), has_more_frames_(false), next_method_(nullptr), next_dex_pc_(0) {
426 }
427
428 bool VisitFrame() OVERRIDE SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
429 if (found_frame_) {
430 mirror::ArtMethod* method = GetMethod();
431 if (method != nullptr && !method->IsRuntimeMethod()) {
432 has_more_frames_ = true;
433 next_method_ = method;
434 next_dex_pc_ = GetDexPc();
435 return false; // End stack walk once next method is found.
436 }
437 } else if (GetFrameHeight() == frame_height_) {
438 found_frame_ = true;
439 }
440 return true;
441 }
442
443 size_t frame_height_;
444 bool found_frame_;
445 bool has_more_frames_;
446 mirror::ArtMethod* next_method_;
447 uint32_t next_dex_pc_;
448 };
449 HasMoreFramesVisitor visitor(thread_, GetNumFrames(), GetFrameHeight());
450 visitor.WalkStack(true);
451 *next_method = visitor.next_method_;
452 *next_dex_pc = visitor.next_dex_pc_;
453 return visitor.has_more_frames_;
454 }
455
DescribeStack(Thread * thread)456 void StackVisitor::DescribeStack(Thread* thread) {
457 struct DescribeStackVisitor : public StackVisitor {
458 explicit DescribeStackVisitor(Thread* thread)
459 : StackVisitor(thread, NULL) {}
460
461 bool VisitFrame() OVERRIDE SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
462 LOG(INFO) << "Frame Id=" << GetFrameId() << " " << DescribeLocation();
463 return true;
464 }
465 };
466 DescribeStackVisitor visitor(thread);
467 visitor.WalkStack(true);
468 }
469
DescribeLocation() const470 std::string StackVisitor::DescribeLocation() const {
471 std::string result("Visiting method '");
472 mirror::ArtMethod* m = GetMethod();
473 if (m == NULL) {
474 return "upcall";
475 }
476 result += PrettyMethod(m);
477 result += StringPrintf("' at dex PC 0x%04x", GetDexPc());
478 if (!IsShadowFrame()) {
479 result += StringPrintf(" (native PC %p)", reinterpret_cast<void*>(GetCurrentQuickFramePc()));
480 }
481 return result;
482 }
483
GetInstrumentationStackFrame(Thread * thread,uint32_t depth)484 static instrumentation::InstrumentationStackFrame& GetInstrumentationStackFrame(Thread* thread,
485 uint32_t depth) {
486 CHECK_LT(depth, thread->GetInstrumentationStack()->size());
487 return thread->GetInstrumentationStack()->at(depth);
488 }
489
SanityCheckFrame() const490 void StackVisitor::SanityCheckFrame() const {
491 if (kIsDebugBuild) {
492 mirror::ArtMethod* method = GetMethod();
493 CHECK_EQ(method->GetClass(), mirror::ArtMethod::GetJavaLangReflectArtMethod());
494 if (cur_quick_frame_ != nullptr) {
495 method->AssertPcIsWithinQuickCode(cur_quick_frame_pc_);
496 // Frame sanity.
497 size_t frame_size = method->GetFrameSizeInBytes();
498 CHECK_NE(frame_size, 0u);
499 // A rough guess at an upper size we expect to see for a frame.
500 // 256 registers
501 // 2 words HandleScope overhead
502 // 3+3 register spills
503 // TODO: this seems architecture specific for the case of JNI frames.
504 // TODO: 083-compiler-regressions ManyFloatArgs shows this estimate is wrong.
505 // const size_t kMaxExpectedFrameSize = (256 + 2 + 3 + 3) * sizeof(word);
506 const size_t kMaxExpectedFrameSize = 2 * KB;
507 CHECK_LE(frame_size, kMaxExpectedFrameSize);
508 size_t return_pc_offset = method->GetReturnPcOffsetInBytes();
509 CHECK_LT(return_pc_offset, frame_size);
510 }
511 }
512 }
513
WalkStack(bool include_transitions)514 void StackVisitor::WalkStack(bool include_transitions) {
515 DCHECK(thread_ == Thread::Current() || thread_->IsSuspended());
516 CHECK_EQ(cur_depth_, 0U);
517 bool exit_stubs_installed = Runtime::Current()->GetInstrumentation()->AreExitStubsInstalled();
518 uint32_t instrumentation_stack_depth = 0;
519
520 for (const ManagedStack* current_fragment = thread_->GetManagedStack(); current_fragment != NULL;
521 current_fragment = current_fragment->GetLink()) {
522 cur_shadow_frame_ = current_fragment->GetTopShadowFrame();
523 cur_quick_frame_ = current_fragment->GetTopQuickFrame();
524 cur_quick_frame_pc_ = current_fragment->GetTopQuickFramePc();
525
526 if (cur_quick_frame_ != NULL) { // Handle quick stack frames.
527 // Can't be both a shadow and a quick fragment.
528 DCHECK(current_fragment->GetTopShadowFrame() == NULL);
529 mirror::ArtMethod* method = cur_quick_frame_->AsMirrorPtr();
530 while (method != NULL) {
531 SanityCheckFrame();
532 bool should_continue = VisitFrame();
533 if (UNLIKELY(!should_continue)) {
534 return;
535 }
536
537 if (context_ != NULL) {
538 context_->FillCalleeSaves(*this);
539 }
540 size_t frame_size = method->GetFrameSizeInBytes();
541 // Compute PC for next stack frame from return PC.
542 size_t return_pc_offset = method->GetReturnPcOffsetInBytes(frame_size);
543 byte* return_pc_addr = reinterpret_cast<byte*>(cur_quick_frame_) + return_pc_offset;
544 uintptr_t return_pc = *reinterpret_cast<uintptr_t*>(return_pc_addr);
545 if (UNLIKELY(exit_stubs_installed)) {
546 // While profiling, the return pc is restored from the side stack, except when walking
547 // the stack for an exception where the side stack will be unwound in VisitFrame.
548 if (GetQuickInstrumentationExitPc() == return_pc) {
549 const instrumentation::InstrumentationStackFrame& instrumentation_frame =
550 GetInstrumentationStackFrame(thread_, instrumentation_stack_depth);
551 instrumentation_stack_depth++;
552 if (GetMethod() == Runtime::Current()->GetCalleeSaveMethod(Runtime::kSaveAll)) {
553 // Skip runtime save all callee frames which are used to deliver exceptions.
554 } else if (instrumentation_frame.interpreter_entry_) {
555 mirror::ArtMethod* callee = Runtime::Current()->GetCalleeSaveMethod(Runtime::kRefsAndArgs);
556 CHECK_EQ(GetMethod(), callee) << "Expected: " << PrettyMethod(callee) << " Found: "
557 << PrettyMethod(GetMethod());
558 } else if (instrumentation_frame.method_ != GetMethod()) {
559 LOG(FATAL) << "Expected: " << PrettyMethod(instrumentation_frame.method_)
560 << " Found: " << PrettyMethod(GetMethod());
561 }
562 if (num_frames_ != 0) {
563 // Check agreement of frame Ids only if num_frames_ is computed to avoid infinite
564 // recursion.
565 CHECK(instrumentation_frame.frame_id_ == GetFrameId())
566 << "Expected: " << instrumentation_frame.frame_id_
567 << " Found: " << GetFrameId();
568 }
569 return_pc = instrumentation_frame.return_pc_;
570 }
571 }
572 cur_quick_frame_pc_ = return_pc;
573 byte* next_frame = reinterpret_cast<byte*>(cur_quick_frame_) + frame_size;
574 cur_quick_frame_ = reinterpret_cast<StackReference<mirror::ArtMethod>*>(next_frame);
575 cur_depth_++;
576 method = cur_quick_frame_->AsMirrorPtr();
577 }
578 } else if (cur_shadow_frame_ != NULL) {
579 do {
580 SanityCheckFrame();
581 bool should_continue = VisitFrame();
582 if (UNLIKELY(!should_continue)) {
583 return;
584 }
585 cur_depth_++;
586 cur_shadow_frame_ = cur_shadow_frame_->GetLink();
587 } while (cur_shadow_frame_ != NULL);
588 }
589 if (include_transitions) {
590 bool should_continue = VisitFrame();
591 if (!should_continue) {
592 return;
593 }
594 }
595 cur_depth_++;
596 }
597 if (num_frames_ != 0) {
598 CHECK_EQ(cur_depth_, num_frames_);
599 }
600 }
601
602 } // namespace art
603