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Diffstat (limited to 'runtime/stack.h')
-rw-r--r-- | runtime/stack.h | 647 |
1 files changed, 647 insertions, 0 deletions
diff --git a/runtime/stack.h b/runtime/stack.h new file mode 100644 index 0000000..fbfacb1 --- /dev/null +++ b/runtime/stack.h @@ -0,0 +1,647 @@ +/* + * Copyright (C) 2011 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#ifndef ART_SRC_STACK_H_ +#define ART_SRC_STACK_H_ + +#include "dex_file.h" +#include "instrumentation.h" +#include "base/macros.h" +#include "oat/runtime/context.h" + +#include <stdint.h> +#include <string> + +namespace art { + +namespace mirror { +class AbstractMethod; +class Object; +} // namespace mirror + +class Context; +class ShadowFrame; +class StackIndirectReferenceTable; +class ScopedObjectAccess; +class Thread; + +// The kind of vreg being accessed in calls to Set/GetVReg. +enum VRegKind { + kReferenceVReg, + kIntVReg, + kFloatVReg, + kLongLoVReg, + kLongHiVReg, + kDoubleLoVReg, + kDoubleHiVReg, + kConstant, + kImpreciseConstant, + kUndefined, +}; + +// ShadowFrame has 3 possible layouts: +// - portable - a unified array of VRegs and references. Precise references need GC maps. +// - interpreter - separate VRegs and reference arrays. References are in the reference array. +// - JNI - just VRegs, but where every VReg holds a reference. +class ShadowFrame { + public: + // Compute size of ShadowFrame in bytes. + static size_t ComputeSize(uint32_t num_vregs) { + return sizeof(ShadowFrame) + (sizeof(uint32_t) * num_vregs) + + (sizeof(mirror::Object*) * num_vregs); + } + + // Create ShadowFrame in heap for deoptimization. + static ShadowFrame* Create(uint32_t num_vregs, ShadowFrame* link, + mirror::AbstractMethod* method, uint32_t dex_pc) { + uint8_t* memory = new uint8_t[ComputeSize(num_vregs)]; + ShadowFrame* sf = new (memory) ShadowFrame(num_vregs, link, method, dex_pc, true); + return sf; + } + + // Create ShadowFrame for interpreter using provided memory. + static ShadowFrame* Create(uint32_t num_vregs, ShadowFrame* link, + mirror::AbstractMethod* method, uint32_t dex_pc, void* memory) { + ShadowFrame* sf = new (memory) ShadowFrame(num_vregs, link, method, dex_pc, true); + return sf; + } + ~ShadowFrame() {} + + bool HasReferenceArray() const { +#if defined(ART_USE_PORTABLE_COMPILER) + return (number_of_vregs_ & kHasReferenceArray) != 0; +#else + return true; +#endif + } + + uint32_t NumberOfVRegs() const { +#if defined(ART_USE_PORTABLE_COMPILER) + return number_of_vregs_ & ~kHasReferenceArray; +#else + return number_of_vregs_; +#endif + } + + void SetNumberOfVRegs(uint32_t number_of_vregs) { +#if defined(ART_USE_PORTABLE_COMPILER) + number_of_vregs_ = number_of_vregs | (number_of_vregs_ & kHasReferenceArray); +#else + UNUSED(number_of_vregs); + UNIMPLEMENTED(FATAL) << "Should only be called when portable is enabled"; +#endif + } + + uint32_t GetDexPC() const { + return dex_pc_; + } + + void SetDexPC(uint32_t dex_pc) { + dex_pc_ = dex_pc; + } + + ShadowFrame* GetLink() const { + return link_; + } + + void SetLink(ShadowFrame* frame) { + DCHECK_NE(this, frame); + link_ = frame; + } + + int32_t GetVReg(size_t i) const { + DCHECK_LT(i, NumberOfVRegs()); + const uint32_t* vreg = &vregs_[i]; + return *reinterpret_cast<const int32_t*>(vreg); + } + + float GetVRegFloat(size_t i) const { + DCHECK_LT(i, NumberOfVRegs()); + // NOTE: Strict-aliasing? + const uint32_t* vreg = &vregs_[i]; + return *reinterpret_cast<const float*>(vreg); + } + + int64_t GetVRegLong(size_t i) const { + DCHECK_LT(i, NumberOfVRegs()); + const uint32_t* vreg = &vregs_[i]; + return *reinterpret_cast<const int64_t*>(vreg); + } + + double GetVRegDouble(size_t i) const { + DCHECK_LT(i, NumberOfVRegs()); + const uint32_t* vreg = &vregs_[i]; + return *reinterpret_cast<const double*>(vreg); + } + + mirror::Object* GetVRegReference(size_t i) const { + DCHECK_LT(i, NumberOfVRegs()); + if (HasReferenceArray()) { + return References()[i]; + } else { + const uint32_t* vreg = &vregs_[i]; + return *reinterpret_cast<mirror::Object* const*>(vreg); + } + } + + // Get view of vregs as range of consecutive arguments starting at i. + uint32_t* GetVRegArgs(size_t i) { + return &vregs_[i]; + } + + void SetVReg(size_t i, int32_t val) { + DCHECK_LT(i, NumberOfVRegs()); + uint32_t* vreg = &vregs_[i]; + *reinterpret_cast<int32_t*>(vreg) = val; + } + + void SetVRegFloat(size_t i, float val) { + DCHECK_LT(i, NumberOfVRegs()); + uint32_t* vreg = &vregs_[i]; + *reinterpret_cast<float*>(vreg) = val; + } + + void SetVRegLong(size_t i, int64_t val) { + DCHECK_LT(i, NumberOfVRegs()); + uint32_t* vreg = &vregs_[i]; + *reinterpret_cast<int64_t*>(vreg) = val; + } + + void SetVRegDouble(size_t i, double val) { + DCHECK_LT(i, NumberOfVRegs()); + uint32_t* vreg = &vregs_[i]; + *reinterpret_cast<double*>(vreg) = val; + } + + void SetVRegReference(size_t i, mirror::Object* val) { + DCHECK_LT(i, NumberOfVRegs()); + uint32_t* vreg = &vregs_[i]; + *reinterpret_cast<mirror::Object**>(vreg) = val; + if (HasReferenceArray()) { + References()[i] = val; + } + } + + mirror::AbstractMethod* GetMethod() const { + DCHECK_NE(method_, static_cast<void*>(NULL)); + return method_; + } + + mirror::Object* GetThisObject() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + mirror::Object* GetThisObject(uint16_t num_ins) const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + ThrowLocation GetCurrentLocationForThrow() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + void SetMethod(mirror::AbstractMethod* method) { +#if defined(ART_USE_PORTABLE_COMPILER) + DCHECK_NE(method, static_cast<void*>(NULL)); + method_ = method; +#else + UNUSED(method); + UNIMPLEMENTED(FATAL) << "Should only be called when portable is enabled"; +#endif + } + + bool Contains(mirror::Object** shadow_frame_entry_obj) const { + if (HasReferenceArray()) { + return ((&References()[0] <= shadow_frame_entry_obj) && + (shadow_frame_entry_obj <= (&References()[NumberOfVRegs() - 1]))); + } else { + uint32_t* shadow_frame_entry = reinterpret_cast<uint32_t*>(shadow_frame_entry_obj); + return ((&vregs_[0] <= shadow_frame_entry) && + (shadow_frame_entry <= (&vregs_[NumberOfVRegs() - 1]))); + } + } + + static size_t LinkOffset() { + return OFFSETOF_MEMBER(ShadowFrame, link_); + } + + static size_t MethodOffset() { + return OFFSETOF_MEMBER(ShadowFrame, method_); + } + + static size_t DexPCOffset() { + return OFFSETOF_MEMBER(ShadowFrame, dex_pc_); + } + + static size_t NumberOfVRegsOffset() { + return OFFSETOF_MEMBER(ShadowFrame, number_of_vregs_); + } + + static size_t VRegsOffset() { + return OFFSETOF_MEMBER(ShadowFrame, vregs_); + } + + private: + ShadowFrame(uint32_t num_vregs, ShadowFrame* link, mirror::AbstractMethod* method, + uint32_t dex_pc, bool has_reference_array) + : number_of_vregs_(num_vregs), link_(link), method_(method), dex_pc_(dex_pc) { + if (has_reference_array) { +#if defined(ART_USE_PORTABLE_COMPILER) + CHECK_LT(num_vregs, static_cast<uint32_t>(kHasReferenceArray)); + number_of_vregs_ |= kHasReferenceArray; +#endif + memset(vregs_, 0, num_vregs * (sizeof(uint32_t) + sizeof(mirror::Object*))); + } else { + memset(vregs_, 0, num_vregs * sizeof(uint32_t)); + } + } + + mirror::Object* const* References() const { + DCHECK(HasReferenceArray()); + const uint32_t* vreg_end = &vregs_[NumberOfVRegs()]; + return reinterpret_cast<mirror::Object* const*>(vreg_end); + } + + mirror::Object** References() { + return const_cast<mirror::Object**>(const_cast<const ShadowFrame*>(this)->References()); + } + +#if defined(ART_USE_PORTABLE_COMPILER) + enum ShadowFrameFlag { + kHasReferenceArray = 1ul << 31 + }; + // TODO: make const in the portable case. + uint32_t number_of_vregs_; +#else + const uint32_t number_of_vregs_; +#endif + // Link to previous shadow frame or NULL. + ShadowFrame* link_; +#if defined(ART_USE_PORTABLE_COMPILER) + // TODO: make const in the portable case. + mirror::AbstractMethod* method_; +#else + mirror::AbstractMethod* const method_; +#endif + uint32_t dex_pc_; + uint32_t vregs_[0]; + + DISALLOW_IMPLICIT_CONSTRUCTORS(ShadowFrame); +}; + +// The managed stack is used to record fragments of managed code stacks. Managed code stacks +// may either be shadow frames or lists of frames using fixed frame sizes. Transition records are +// necessary for transitions between code using different frame layouts and transitions into native +// code. +class PACKED(4) ManagedStack { + public: + ManagedStack() + : link_(NULL), top_shadow_frame_(NULL), top_quick_frame_(NULL), top_quick_frame_pc_(0) {} + + void PushManagedStackFragment(ManagedStack* fragment) { + // Copy this top fragment into given fragment. + memcpy(fragment, this, sizeof(ManagedStack)); + // Clear this fragment, which has become the top. + memset(this, 0, sizeof(ManagedStack)); + // Link our top fragment onto the given fragment. + link_ = fragment; + } + + void PopManagedStackFragment(const ManagedStack& fragment) { + DCHECK(&fragment == link_); + // Copy this given fragment back to the top. + memcpy(this, &fragment, sizeof(ManagedStack)); + } + + ManagedStack* GetLink() const { + return link_; + } + + mirror::AbstractMethod** GetTopQuickFrame() const { + return top_quick_frame_; + } + + void SetTopQuickFrame(mirror::AbstractMethod** top) { + DCHECK(top_shadow_frame_ == NULL); + top_quick_frame_ = top; + } + + uintptr_t GetTopQuickFramePc() const { + return top_quick_frame_pc_; + } + + void SetTopQuickFramePc(uintptr_t pc) { + DCHECK(top_shadow_frame_ == NULL); + top_quick_frame_pc_ = pc; + } + + static size_t TopQuickFrameOffset() { + return OFFSETOF_MEMBER(ManagedStack, top_quick_frame_); + } + + static size_t TopQuickFramePcOffset() { + return OFFSETOF_MEMBER(ManagedStack, top_quick_frame_pc_); + } + + ShadowFrame* PushShadowFrame(ShadowFrame* new_top_frame) { + DCHECK(top_quick_frame_ == NULL); + ShadowFrame* old_frame = top_shadow_frame_; + top_shadow_frame_ = new_top_frame; + new_top_frame->SetLink(old_frame); + return old_frame; + } + + ShadowFrame* PopShadowFrame() { + DCHECK(top_quick_frame_ == NULL); + CHECK(top_shadow_frame_ != NULL); + ShadowFrame* frame = top_shadow_frame_; + top_shadow_frame_ = frame->GetLink(); + return frame; + } + + ShadowFrame* GetTopShadowFrame() const { + return top_shadow_frame_; + } + + void SetTopShadowFrame(ShadowFrame* top) { + DCHECK(top_quick_frame_ == NULL); + top_shadow_frame_ = top; + } + + static size_t TopShadowFrameOffset() { + return OFFSETOF_MEMBER(ManagedStack, top_shadow_frame_); + } + + size_t NumJniShadowFrameReferences() const; + + bool ShadowFramesContain(mirror::Object** shadow_frame_entry) const; + + private: + ManagedStack* link_; + ShadowFrame* top_shadow_frame_; + mirror::AbstractMethod** top_quick_frame_; + uintptr_t top_quick_frame_pc_; +}; + +class StackVisitor { + protected: + StackVisitor(Thread* thread, Context* context) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + public: + virtual ~StackVisitor() {} + + // Return 'true' if we should continue to visit more frames, 'false' to stop. + virtual bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) = 0; + + void WalkStack(bool include_transitions = false) + SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + mirror::AbstractMethod* GetMethod() const { + if (cur_shadow_frame_ != NULL) { + return cur_shadow_frame_->GetMethod(); + } else if (cur_quick_frame_ != NULL) { + return *cur_quick_frame_; + } else { + return NULL; + } + } + + bool IsShadowFrame() const { + return cur_shadow_frame_ != NULL; + } + + uint32_t GetDexPc() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + mirror::Object* GetThisObject() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + size_t GetNativePcOffset() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + uintptr_t* CalleeSaveAddress(int num, size_t frame_size) const { + // Callee saves are held at the top of the frame + DCHECK(GetMethod() != NULL); + byte* save_addr = + reinterpret_cast<byte*>(cur_quick_frame_) + frame_size - ((num + 1) * kPointerSize); +#if defined(__i386__) + save_addr -= kPointerSize; // account for return address +#endif + return reinterpret_cast<uintptr_t*>(save_addr); + } + + // Returns the height of the stack in the managed stack frames, including transitions. + size_t GetFrameHeight() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { + return GetNumFrames() - cur_depth_ - 1; + } + + // Returns a frame ID for JDWP use, starting from 1. + size_t GetFrameId() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { + return GetFrameHeight() + 1; + } + + size_t GetNumFrames() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { + if (num_frames_ == 0) { + num_frames_ = ComputeNumFrames(thread_); + } + return num_frames_; + } + + uint32_t GetVReg(mirror::AbstractMethod* m, uint16_t vreg, VRegKind kind) const + SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + void SetVReg(mirror::AbstractMethod* m, uint16_t vreg, uint32_t new_value, VRegKind kind) + SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + uintptr_t GetGPR(uint32_t reg) const; + void SetGPR(uint32_t reg, uintptr_t value); + + uint32_t GetVReg(mirror::AbstractMethod** cur_quick_frame, const DexFile::CodeItem* code_item, + uint32_t core_spills, uint32_t fp_spills, size_t frame_size, + uint16_t vreg) const { + int offset = GetVRegOffset(code_item, core_spills, fp_spills, frame_size, vreg); + DCHECK_EQ(cur_quick_frame, GetCurrentQuickFrame()); + byte* vreg_addr = reinterpret_cast<byte*>(cur_quick_frame) + offset; + return *reinterpret_cast<uint32_t*>(vreg_addr); + } + + uintptr_t GetReturnPc() const; + + void SetReturnPc(uintptr_t new_ret_pc); + + /* + * Return sp-relative offset for a Dalvik virtual register, compiler + * spill or Method* in bytes using Method*. + * Note that (reg >= 0) refers to a Dalvik register, (reg == -2) + * denotes Method* and (reg <= -3) denotes a compiler temp. + * + * +------------------------+ + * | IN[ins-1] | {Note: resides in caller's frame} + * | . | + * | IN[0] | + * | caller's Method* | + * +========================+ {Note: start of callee's frame} + * | core callee-save spill | {variable sized} + * +------------------------+ + * | fp callee-save spill | + * +------------------------+ + * | filler word | {For compatibility, if V[locals-1] used as wide + * +------------------------+ + * | V[locals-1] | + * | V[locals-2] | + * | . | + * | . | ... (reg == 2) + * | V[1] | ... (reg == 1) + * | V[0] | ... (reg == 0) <---- "locals_start" + * +------------------------+ + * | Compiler temps | ... (reg == -2) + * | | ... (reg == -3) + * | | ... (reg == -4) + * +------------------------+ + * | stack alignment padding| {0 to (kStackAlignWords-1) of padding} + * +------------------------+ + * | OUT[outs-1] | + * | OUT[outs-2] | + * | . | + * | OUT[0] | + * | curMethod* | ... (reg == -1) <<== sp, 16-byte aligned + * +========================+ + */ + static int GetVRegOffset(const DexFile::CodeItem* code_item, + uint32_t core_spills, uint32_t fp_spills, + size_t frame_size, int reg) { + DCHECK_EQ(frame_size & (kStackAlignment - 1), 0U); + int num_spills = __builtin_popcount(core_spills) + __builtin_popcount(fp_spills) + 1; // Filler. + int num_ins = code_item->ins_size_; + int num_regs = code_item->registers_size_ - num_ins; + int locals_start = frame_size - ((num_spills + num_regs) * sizeof(uint32_t)); + if (reg == -2) { + return 0; // Method* + } else if (reg <= -3) { + return locals_start - ((reg + 1) * sizeof(uint32_t)); // Compiler temp. + } else if (reg < num_regs) { + return locals_start + (reg * sizeof(uint32_t)); // Dalvik local reg. + } else { + return frame_size + ((reg - num_regs) * sizeof(uint32_t)) + sizeof(uint32_t); // Dalvik in. + } + } + + uintptr_t GetCurrentQuickFramePc() const { + return cur_quick_frame_pc_; + } + + mirror::AbstractMethod** GetCurrentQuickFrame() const { + return cur_quick_frame_; + } + + ShadowFrame* GetCurrentShadowFrame() const { + return cur_shadow_frame_; + } + + StackIndirectReferenceTable* GetCurrentSirt() const { + mirror::AbstractMethod** sp = GetCurrentQuickFrame(); + ++sp; // Skip Method*; SIRT comes next; + return reinterpret_cast<StackIndirectReferenceTable*>(sp); + } + + std::string DescribeLocation() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + static size_t ComputeNumFrames(Thread* thread) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + static void DescribeStack(Thread* thread) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + private: + + instrumentation::InstrumentationStackFrame GetInstrumentationStackFrame(uint32_t depth) const; + + void SanityCheckFrame() const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); + + Thread* const thread_; + ShadowFrame* cur_shadow_frame_; + mirror::AbstractMethod** cur_quick_frame_; + uintptr_t cur_quick_frame_pc_; + // Lazily computed, number of frames in the stack. + size_t num_frames_; + // Depth of the frame we're currently at. + size_t cur_depth_; + protected: + Context* const context_; +}; + +class VmapTable { + public: + explicit VmapTable(const uint16_t* table) : table_(table) { + } + + uint16_t operator[](size_t i) const { + return table_[i + 1]; + } + + size_t size() const { + return table_[0]; + } + + // Is the dex register 'vreg' in the context or on the stack? Should not be called when the + // 'kind' is unknown or constant. + bool IsInContext(size_t vreg, uint32_t& vmap_offset, VRegKind kind) const { + DCHECK(kind == kReferenceVReg || kind == kIntVReg || kind == kFloatVReg || + kind == kLongLoVReg || kind == kLongHiVReg || kind == kDoubleLoVReg || + kind == kDoubleHiVReg || kind == kImpreciseConstant); + vmap_offset = 0xEBAD0FF5; + // TODO: take advantage of the registers being ordered + // TODO: we treat kImpreciseConstant as an integer below, need to ensure that such values + // are never promoted to floating point registers. + bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg); + bool in_floats = false; + for (size_t i = 0; i < size(); ++i) { + // Stop if we find what we are are looking for. + if ((table_[i + 1] == vreg) && (in_floats == is_float)) { + vmap_offset = i; + return true; + } + // 0xffff is the marker for LR (return PC on x86), following it are spilled float registers. + if (table_[i + 1] == 0xffff) { + in_floats = true; + } + } + return false; + } + + // Compute the register number that corresponds to the entry in the vmap (vmap_offset, computed + // by IsInContext above). If the kind is floating point then the result will be a floating point + // register number, otherwise it will be an integer register number. + uint32_t ComputeRegister(uint32_t spill_mask, uint32_t vmap_offset, VRegKind kind) const { + // Compute the register we need to load from the context. + DCHECK(kind == kReferenceVReg || kind == kIntVReg || kind == kFloatVReg || + kind == kLongLoVReg || kind == kLongHiVReg || kind == kDoubleLoVReg || + kind == kDoubleHiVReg || kind == kImpreciseConstant); + // TODO: we treat kImpreciseConstant as an integer below, need to ensure that such values + // are never promoted to floating point registers. + bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg); + uint32_t matches = 0; + if (is_float) { + while (table_[matches] != 0xffff) { + matches++; + } + } + CHECK_LT(vmap_offset - matches, static_cast<uint32_t>(__builtin_popcount(spill_mask))); + uint32_t spill_shifts = 0; + while (matches != (vmap_offset + 1)) { + DCHECK_NE(spill_mask, 0u); + matches += spill_mask & 1; // Add 1 if the low bit is set + spill_mask >>= 1; + spill_shifts++; + } + spill_shifts--; // wind back one as we want the last match + return spill_shifts; + } + private: + const uint16_t* table_; +}; + +} // namespace art + +#endif // ART_SRC_STACK_H_ |