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* Copyright (C) 2013 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
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* See the License for the specific language governing permissions and
* limitations under the License.
#include <stdint.h>
#include "base/arena_containers.h"
#include "base/bit_utils.h"
#include "base/scoped_arena_containers.h"
#include "dex_file.h"
#include "dex_instruction.h"
#include "dex_types.h"
#include "invoke_type.h"
#include "mir_field_info.h"
#include "mir_method_info.h"
#include "reg_location.h"
#include "reg_storage.h"
#include "utils/arena_bit_vector.h"
namespace art {
struct CompilationUnit;
class DexCompilationUnit;
class DexFileMethodInliner;
class GlobalValueNumbering;
class GvnDeadCodeElimination;
class PassManager;
class TypeInference;
// Forward declaration.
class MIRGraph;
enum DataFlowAttributePos {
kUA = 0,
kFormatExtended, // Extended format for extended MIRs.
kNullCheckA, // Null check of A.
kNullCheckB, // Null check of B.
kNullCheckOut0, // Null check out outgoing arg0.
kDstNonNull, // May assume dst is non-null.
kRetNonNull, // May assume retval is non-null.
kNullTransferSrc0, // Object copy src[0] -> dst.
kNullTransferSrcN, // Phi null check state transfer.
kRangeCheckC, // Range check of C.
kCheckCastA, // Check cast of A.
kSameTypeAB, // A and B have the same type but it can be core/ref/fp (IF_cc).
kUsesMethodStar, // Implicit use of Method*.
kUsesIField, // Accesses an instance field (IGET/IPUT).
kUsesSField, // Accesses a static field (SGET/SPUT).
kCanInitializeClass, // Can trigger class initialization (SGET/SPUT/INVOKE_STATIC).
kDoLVN, // Worth computing local value numbers.
#define DF_NOP UINT64_C(0)
#define DF_UA (UINT64_C(1) << kUA)
#define DF_UB (UINT64_C(1) << kUB)
#define DF_UC (UINT64_C(1) << kUC)
#define DF_A_WIDE (UINT64_C(1) << kAWide)
#define DF_B_WIDE (UINT64_C(1) << kBWide)
#define DF_C_WIDE (UINT64_C(1) << kCWide)
#define DF_DA (UINT64_C(1) << kDA)
#define DF_IS_MOVE (UINT64_C(1) << kIsMove)
#define DF_SETS_CONST (UINT64_C(1) << kSetsConst)
#define DF_FORMAT_35C (UINT64_C(1) << kFormat35c)
#define DF_FORMAT_3RC (UINT64_C(1) << kFormat3rc)
#define DF_FORMAT_EXTENDED (UINT64_C(1) << kFormatExtended)
#define DF_NULL_CHK_A (UINT64_C(1) << kNullCheckA)
#define DF_NULL_CHK_B (UINT64_C(1) << kNullCheckB)
#define DF_NULL_CHK_OUT0 (UINT64_C(1) << kNullCheckOut0)
#define DF_NON_NULL_DST (UINT64_C(1) << kDstNonNull)
#define DF_NON_NULL_RET (UINT64_C(1) << kRetNonNull)
#define DF_NULL_TRANSFER_0 (UINT64_C(1) << kNullTransferSrc0)
#define DF_NULL_TRANSFER_N (UINT64_C(1) << kNullTransferSrcN)
#define DF_RANGE_CHK_C (UINT64_C(1) << kRangeCheckC)
#define DF_CHK_CAST (UINT64_C(1) << kCheckCastA)
#define DF_FP_A (UINT64_C(1) << kFPA)
#define DF_FP_B (UINT64_C(1) << kFPB)
#define DF_FP_C (UINT64_C(1) << kFPC)
#define DF_CORE_A (UINT64_C(1) << kCoreA)
#define DF_CORE_B (UINT64_C(1) << kCoreB)
#define DF_CORE_C (UINT64_C(1) << kCoreC)
#define DF_REF_A (UINT64_C(1) << kRefA)
#define DF_REF_B (UINT64_C(1) << kRefB)
#define DF_REF_C (UINT64_C(1) << kRefC)
#define DF_SAME_TYPE_AB (UINT64_C(1) << kSameTypeAB)
#define DF_UMS (UINT64_C(1) << kUsesMethodStar)
#define DF_IFIELD (UINT64_C(1) << kUsesIField)
#define DF_SFIELD (UINT64_C(1) << kUsesSField)
#define DF_CLINIT (UINT64_C(1) << kCanInitializeClass)
#define DF_LVN (UINT64_C(1) << kDoLVN)
#define DF_HAS_USES (DF_UA | DF_UB | DF_UC)
#define DF_HAS_DEFS (DF_DA)
#define DF_A_IS_REG (DF_UA | DF_DA)
#define DF_B_IS_REG (DF_UB)
#define DF_C_IS_REG (DF_UC)
#define DF_USES_FP (DF_FP_A | DF_FP_B | DF_FP_C)
enum OatMethodAttributes {
kIsLeaf, // Method is leaf.
#define METHOD_IS_LEAF (1 << kIsLeaf)
// Minimum field size to contain Dalvik v_reg number.
#define VREG_NUM_WIDTH 16
#define MIR_IGNORE_NULL_CHECK (1 << kMIRIgnoreNullCheck)
#define MIR_IGNORE_RANGE_CHECK (1 << kMIRIgnoreRangeCheck)
#define MIR_IGNORE_CHECK_CAST (1 << kMIRIgnoreCheckCast)
#define MIR_STORE_NON_NULL_VALUE (1 << kMIRStoreNonNullValue)
#define MIR_CLASS_IS_INITIALIZED (1 << kMIRClassIsInitialized)
#define MIR_CLASS_IS_IN_DEX_CACHE (1 << kMIRClassIsInDexCache)
#define MIR_IGNORE_DIV_ZERO_CHECK (1 << kMirIgnoreDivZeroCheck)
#define MIR_INLINED (1 << kMIRInlined)
#define MIR_INLINED_PRED (1 << kMIRInlinedPred)
#define MIR_CALLEE (1 << kMIRCallee)
#define MIR_IGNORE_SUSPEND_CHECK (1 << kMIRIgnoreSuspendCheck)
#define MIR_DUP (1 << kMIRDup)
#define MIR_MARK (1 << kMIRMark)
#define MIR_STORE_NON_TEMPORAL (1 << kMIRStoreNonTemporal)
#define BLOCK_NAME_LEN 80
typedef uint16_t BasicBlockId;
static const BasicBlockId NullBasicBlockId = 0;
static constexpr bool kLeafOptimization = false;
* In general, vreg/sreg describe Dalvik registers that originated with dx. However,
* it is useful to have compiler-generated temporary registers and have them treated
* in the same manner as dx-generated virtual registers. This struct records the SSA
* name of compiler-introduced temporaries.
struct CompilerTemp {
int32_t v_reg; // Virtual register number for temporary.
int32_t s_reg_low; // SSA name for low Dalvik word.
enum CompilerTempType {
kCompilerTempVR, // A virtual register temporary.
kCompilerTempSpecialMethodPtr, // Temporary that keeps track of current method pointer.
kCompilerTempBackend, // Temporary that is used by backend.
// When debug option enabled, records effectiveness of null and range check elimination.
struct Checkstats {
int32_t null_checks;
int32_t null_checks_eliminated;
int32_t range_checks;
int32_t range_checks_eliminated;
// Dataflow attributes of a basic block.
struct BasicBlockDataFlow {
ArenaBitVector* use_v;
ArenaBitVector* def_v;
ArenaBitVector* live_in_v;
int32_t* vreg_to_ssa_map_exit;
* Normalized use/def for a MIR operation using SSA names rather than vregs. Note that
* uses/defs retain the Dalvik convention that long operations operate on a pair of 32-bit
* vregs. For example, "ADD_LONG v0, v2, v3" would have 2 defs (v0/v1) and 4 uses (v2/v3, v4/v5).
* Following SSA renaming, this is the primary struct used by code generators to locate
* operand and result registers. This is a somewhat confusing and unhelpful convention that
* we may want to revisit in the future.
* 1. Add accessors for uses/defs and make data private
* 2. Change fp_use/fp_def to a bit array (could help memory usage)
* 3. Combine array storage into internal array and handled via accessors from 1.
struct SSARepresentation {
int32_t* uses;
int32_t* defs;
uint16_t num_uses_allocated;
uint16_t num_defs_allocated;
uint16_t num_uses;
uint16_t num_defs;
static uint32_t GetStartUseIndex(Instruction::Code opcode);
* The Midlevel Intermediate Representation node, which may be largely considered a
* wrapper around a Dalvik byte code.
class MIR : public ArenaObject<kArenaAllocMIR> {
* TODO: remove embedded DecodedInstruction to save space, keeping only opcode. Recover
* additional fields on as-needed basis. Question: how to support MIR Pseudo-ops; probably
* need to carry aux data pointer.
struct DecodedInstruction {
uint32_t vA;
uint32_t vB;
uint64_t vB_wide; /* for k51l */
uint32_t vC;
uint32_t arg[5]; /* vC/D/E/F/G in invoke or filled-new-array */
Instruction::Code opcode;
explicit DecodedInstruction():vA(0), vB(0), vB_wide(0), vC(0), opcode(Instruction::NOP) {
* Given a decoded instruction representing a const bytecode, it updates
* the out arguments with proper values as dictated by the constant bytecode.
bool GetConstant(int64_t* ptr_value, bool* wide) const;
static bool IsPseudoMirOp(Instruction::Code opcode) {
return static_cast<int>(opcode) >= static_cast<int>(kMirOpFirst);
static bool IsPseudoMirOp(int opcode) {
return opcode >= static_cast<int>(kMirOpFirst);
bool IsInvoke() const {
return ((FlagsOf() & Instruction::kInvoke) == Instruction::kInvoke);
bool IsStore() const {
return ((FlagsOf() & Instruction::kStore) == Instruction::kStore);
bool IsLoad() const {
return ((FlagsOf() & Instruction::kLoad) == Instruction::kLoad);
bool IsConditionalBranch() const {
return (FlagsOf() == (Instruction::kContinue | Instruction::kBranch));
* @brief Is the register C component of the decoded instruction a constant?
bool IsCFieldOrConstant() const {
return ((FlagsOf() & Instruction::kRegCFieldOrConstant) == Instruction::kRegCFieldOrConstant);
* @brief Is the register C component of the decoded instruction a constant?
bool IsBFieldOrConstant() const {
return ((FlagsOf() & Instruction::kRegBFieldOrConstant) == Instruction::kRegBFieldOrConstant);
bool IsCast() const {
return ((FlagsOf() & Instruction::kCast) == Instruction::kCast);
* @brief Does the instruction clobber memory?
* @details Clobber means that the instruction changes the memory not in a punctual way.
* Therefore any supposition on memory aliasing or memory contents should be disregarded
* when crossing such an instruction.
bool Clobbers() const {
return ((FlagsOf() & Instruction::kClobber) == Instruction::kClobber);
bool IsLinear() const {
return (FlagsOf() & (Instruction::kAdd | Instruction::kSubtract)) != 0;
int FlagsOf() const;
} dalvikInsn;
NarrowDexOffset offset; // Offset of the instruction in code units.
uint16_t optimization_flags;
int16_t m_unit_index; // From which method was this MIR included
BasicBlockId bb;
MIR* next;
SSARepresentation* ssa_rep;
union {
// Incoming edges for phi node.
BasicBlockId* phi_incoming;
// Establish link from check instruction (kMirOpCheck) to the actual throwing instruction.
MIR* throw_insn;
// Branch condition for fused cmp or select.
ConditionCode ccode;
// IGET/IPUT lowering info index, points to MIRGraph::ifield_lowering_infos_. Due to limit on
// the number of code points (64K) and size of IGET/IPUT insn (2), this will never exceed 32K.
uint32_t ifield_lowering_info;
// SGET/SPUT lowering info index, points to MIRGraph::sfield_lowering_infos_. Due to limit on
// the number of code points (64K) and size of SGET/SPUT insn (2), this will never exceed 32K.
uint32_t sfield_lowering_info;
// INVOKE data index, points to MIRGraph::method_lowering_infos_. Also used for inlined
// CONST and MOVE insn (with MIR_CALLEE) to remember the invoke for type inference.
uint32_t method_lowering_info;
} meta;
explicit MIR() : offset(0), optimization_flags(0), m_unit_index(0), bb(NullBasicBlockId),
next(nullptr), ssa_rep(nullptr) {
memset(&meta, 0, sizeof(meta));
uint32_t GetStartUseIndex() const {
return SSARepresentation::GetStartUseIndex(dalvikInsn.opcode);
MIR* Copy(CompilationUnit *c_unit);
MIR* Copy(MIRGraph* mir_Graph);
struct SuccessorBlockInfo;
class BasicBlock : public DeletableArenaObject<kArenaAllocBB> {
BasicBlock(BasicBlockId block_id, BBType type, ArenaAllocator* allocator)
: id(block_id),
dfs_id(), start_offset(), fall_through(), taken(), i_dom(), nesting_depth(),
visited(), hidden(), catch_entry(), explicit_throw(), conditional_branch(),
terminated_by_return(), dominates_return(), use_lvn(), first_mir_insn(),
last_mir_insn(), data_flow_info(), dominators(), i_dominated(), dom_frontier(),
successor_blocks(allocator->Adapter(kArenaAllocSuccessor)) {
BasicBlockId id;
BasicBlockId dfs_id;
NarrowDexOffset start_offset; // Offset in code units.
BasicBlockId fall_through;
BasicBlockId taken;
BasicBlockId i_dom; // Immediate dominator.
uint16_t nesting_depth;
BBType block_type:4;
BlockListType successor_block_list_type:4;
bool visited:1;
bool hidden:1;
bool catch_entry:1;
bool explicit_throw:1;
bool conditional_branch:1;
bool terminated_by_return:1; // Block ends with a Dalvik return opcode.
bool dominates_return:1; // Is a member of return extended basic block.
bool use_lvn:1; // Run local value numbering on this block.
MIR* first_mir_insn;
MIR* last_mir_insn;
BasicBlockDataFlow* data_flow_info;
ArenaBitVector* dominators;
ArenaBitVector* i_dominated; // Set nodes being immediately dominated.
ArenaBitVector* dom_frontier; // Dominance frontier.
ArenaVector<BasicBlockId> predecessors;
ArenaVector<SuccessorBlockInfo*> successor_blocks;
void AppendMIR(MIR* mir);
void AppendMIRList(MIR* first_list_mir, MIR* last_list_mir);
void AppendMIRList(const std::vector<MIR*>& insns);
void PrependMIR(MIR* mir);
void PrependMIRList(MIR* first_list_mir, MIR* last_list_mir);
void PrependMIRList(const std::vector<MIR*>& to_add);
void InsertMIRAfter(MIR* current_mir, MIR* new_mir);
void InsertMIRListAfter(MIR* insert_after, MIR* first_list_mir, MIR* last_list_mir);
MIR* FindPreviousMIR(MIR* mir);
void InsertMIRBefore(MIR* insert_before, MIR* list);
void InsertMIRListBefore(MIR* insert_before, MIR* first_list_mir, MIR* last_list_mir);
bool RemoveMIR(MIR* mir);
bool RemoveMIRList(MIR* first_list_mir, MIR* last_list_mir);
BasicBlock* Copy(CompilationUnit* c_unit);
BasicBlock* Copy(MIRGraph* mir_graph);
* @brief Reset the optimization_flags field of each MIR.
void ResetOptimizationFlags(uint16_t reset_flags);
* @brief Kill the BasicBlock.
* @details Unlink predecessors and successors, remove all MIRs, set the block type to kDead
* and set hidden to true.
void Kill(MIRGraph* mir_graph);
* @brief Is ssa_reg the last SSA definition of that VR in the block?
bool IsSSALiveOut(const CompilationUnit* c_unit, int ssa_reg);
* @brief Replace the edge going to old_bb to now go towards new_bb.
bool ReplaceChild(BasicBlockId old_bb, BasicBlockId new_bb);
* @brief Erase the predecessor old_pred.
void ErasePredecessor(BasicBlockId old_pred);
* @brief Update the predecessor array from old_pred to new_pred.
void UpdatePredecessor(BasicBlockId old_pred, BasicBlockId new_pred);
* @brief Return first non-Phi insn.
MIR* GetFirstNonPhiInsn();
* @brief Checks whether the block ends with if-nez or if-eqz that branches to
* the given successor only if the register in not zero.
bool BranchesToSuccessorOnlyIfNotZero(BasicBlockId succ_id) const {
if (last_mir_insn == nullptr) {
return false;
Instruction::Code last_opcode = last_mir_insn->dalvikInsn.opcode;
return ((last_opcode == Instruction::IF_EQZ && fall_through == succ_id) ||
(last_opcode == Instruction::IF_NEZ && taken == succ_id)) &&
// Make sure the other successor isn't the same (empty if), b/21614284.
(fall_through != taken);
* @brief Used to obtain the next MIR that follows unconditionally.
* @details The implementation does not guarantee that a MIR does not
* follow even if this method returns nullptr.
* @param mir_graph the MIRGraph.
* @param current The MIR for which to find an unconditional follower.
* @return Returns the following MIR if one can be found.
MIR* GetNextUnconditionalMir(MIRGraph* mir_graph, MIR* current);
bool IsExceptionBlock() const;
* The "blocks" field in "successor_block_list" points to an array of elements with the type
* "SuccessorBlockInfo". For catch blocks, key is type index for the exception. For switch
* blocks, key is the case value.
struct SuccessorBlockInfo {
BasicBlockId block;
int key;
* @class ChildBlockIterator
* @brief Enable an easy iteration of the children.
class ChildBlockIterator {
* @brief Constructs a child iterator.
* @param bb The basic whose children we need to iterate through.
* @param mir_graph The MIRGraph used to get the basic block during iteration.
ChildBlockIterator(BasicBlock* bb, MIRGraph* mir_graph);
BasicBlock* Next();
BasicBlock* basic_block_;
MIRGraph* mir_graph_;
bool visited_fallthrough_;
bool visited_taken_;
bool have_successors_;
ArenaVector<SuccessorBlockInfo*>::const_iterator successor_iter_;
* Collection of information describing an invoke, and the destination of
* the subsequent MOVE_RESULT (if applicable). Collected as a unit to enable
* more efficient invoke code generation.
struct CallInfo {
size_t num_arg_words; // Note: word count, not arg count.
RegLocation* args; // One for each word of arguments.
RegLocation result; // Eventual target of MOVE_RESULT.
int opt_flags;
InvokeType type;
uint32_t dex_idx;
MethodReference method_ref;
uint32_t index; // Method idx for invokes, type idx for FilledNewArray.
uintptr_t direct_code;
uintptr_t direct_method;
RegLocation target; // Target of following move_result.
bool skip_this;
bool is_range;
DexOffset offset; // Offset in code units.
MIR* mir;
int32_t string_init_offset;
const RegLocation bad_loc = {kLocDalvikFrame, 0, 0, 0, 0, 0, 0, 0, 0, RegStorage(), INVALID_SREG,
class MIRGraph {
MIRGraph(CompilationUnit* cu, ArenaAllocator* arena);
virtual ~MIRGraph();
* Examine the graph to determine whether it's worthwile to spend the time compiling
* this method.
bool SkipCompilation(std::string* skip_message);
* Should we skip the compilation of this method based on its name?
bool SkipCompilationByName(const std::string& methodname);
* Parse dex method and add MIR at current insert point. Returns id (which is
* actually the index of the method in the m_units_ array).
void InlineMethod(const DexFile::CodeItem* code_item, uint32_t access_flags,
InvokeType invoke_type, uint16_t class_def_idx,
uint32_t method_idx, jobject class_loader, const DexFile& dex_file);
/* Find existing block */
BasicBlock* FindBlock(DexOffset code_offset,
ScopedArenaVector<uint16_t>* dex_pc_to_block_map) {
return FindBlock(code_offset, false, nullptr, dex_pc_to_block_map);
const uint16_t* GetCurrentInsns() const {
return current_code_item_->insns_;
* @brief Used to obtain the raw dex bytecode instruction pointer.
* @param m_unit_index The method index in MIRGraph (caused by having multiple methods).
* This is guaranteed to contain index 0 which is the base method being compiled.
* @return Returns the raw instruction pointer.
const uint16_t* GetInsns(int m_unit_index) const;
* @brief Used to obtain the raw data table.
* @param mir sparse switch, packed switch, of fill-array-data
* @param table_offset The table offset from start of method.
* @return Returns the raw table pointer.
const uint16_t* GetTable(MIR* mir, uint32_t table_offset) const {
return GetInsns(mir->m_unit_index) + mir->offset + static_cast<int32_t>(table_offset);
unsigned int GetNumBlocks() const {
return block_list_.size();
* @brief Provides the total size in code units of all instructions in MIRGraph.
* @details Includes the sizes of all methods in compilation unit.
* @return Returns the cumulative sum of all insn sizes (in code units).
size_t GetNumDalvikInsns() const;
ArenaBitVector* GetTryBlockAddr() const {
return try_block_addr_;
BasicBlock* GetEntryBlock() const {
return entry_block_;
BasicBlock* GetExitBlock() const {
return exit_block_;
BasicBlock* GetBasicBlock(unsigned int block_id) const {
DCHECK_LT(block_id, block_list_.size()); // NOTE: NullBasicBlockId is 0.
return (block_id == NullBasicBlockId) ? nullptr : block_list_[block_id];
size_t GetBasicBlockListCount() const {
return block_list_.size();
const ArenaVector<BasicBlock*>& GetBlockList() {
return block_list_;
const ArenaVector<BasicBlockId>& GetDfsOrder() {
return dfs_order_;
const ArenaVector<BasicBlockId>& GetDfsPostOrder() {
return dfs_post_order_;
const ArenaVector<BasicBlockId>& GetDomPostOrder() {
return dom_post_order_traversal_;
int GetDefCount() const {
return def_count_;
ArenaAllocator* GetArena() const {
return arena_;
void EnableOpcodeCounting() {
opcode_count_ = arena_->AllocArray<int>(kNumPackedOpcodes, kArenaAllocMisc);
void ShowOpcodeStats();
DexCompilationUnit* GetCurrentDexCompilationUnit() const {
return m_units_[current_method_];
* @brief Dump a CFG into a dot file format.
* @param dir_prefix the directory the file will be created in.
* @param all_blocks does the dumper use all the basic blocks or use the reachable blocks.
* @param suffix does the filename require a suffix or not (default = nullptr).
void DumpCFG(const char* dir_prefix, bool all_blocks, const char* suffix = nullptr);
bool HasCheckCast() const {
return (merged_df_flags_ & DF_CHK_CAST) != 0u;
bool HasFieldAccess() const {
return (merged_df_flags_ & (DF_IFIELD | DF_SFIELD)) != 0u;
bool HasStaticFieldAccess() const {
return (merged_df_flags_ & DF_SFIELD) != 0u;
bool HasInvokes() const {
// NOTE: These formats include the rare filled-new-array/range.
return (merged_df_flags_ & (DF_FORMAT_35C | DF_FORMAT_3RC)) != 0u;
void DoCacheFieldLoweringInfo();
const MirIFieldLoweringInfo& GetIFieldLoweringInfo(MIR* mir) const {
return GetIFieldLoweringInfo(mir->meta.ifield_lowering_info);
const MirIFieldLoweringInfo& GetIFieldLoweringInfo(uint32_t lowering_info) const {
DCHECK_LT(lowering_info, ifield_lowering_infos_.size());
return ifield_lowering_infos_[lowering_info];
size_t GetIFieldLoweringInfoCount() const {
return ifield_lowering_infos_.size();
const MirSFieldLoweringInfo& GetSFieldLoweringInfo(MIR* mir) const {
return GetSFieldLoweringInfo(mir->meta.sfield_lowering_info);
const MirSFieldLoweringInfo& GetSFieldLoweringInfo(uint32_t lowering_info) const {
DCHECK_LT(lowering_info, sfield_lowering_infos_.size());
return sfield_lowering_infos_[lowering_info];
size_t GetSFieldLoweringInfoCount() const {
return sfield_lowering_infos_.size();
void DoCacheMethodLoweringInfo();
const MirMethodLoweringInfo& GetMethodLoweringInfo(MIR* mir) const {
return GetMethodLoweringInfo(mir->meta.method_lowering_info);
const MirMethodLoweringInfo& GetMethodLoweringInfo(uint32_t lowering_info) const {
DCHECK_LT(lowering_info, method_lowering_infos_.size());
return method_lowering_infos_[lowering_info];
size_t GetMethodLoweringInfoCount() const {
return method_lowering_infos_.size();
void ComputeInlineIFieldLoweringInfo(uint16_t field_idx, MIR* invoke, MIR* iget_or_iput);
void InitRegLocations();
void RemapRegLocations();
void DumpRegLocTable(RegLocation* table, int count);
void BasicBlockOptimizationStart();
void BasicBlockOptimization();
void BasicBlockOptimizationEnd();
void StringChange();
const ArenaVector<BasicBlockId>& GetTopologicalSortOrder() {
return topological_order_;
const ArenaVector<BasicBlockId>& GetTopologicalSortOrderLoopEnds() {
return topological_order_loop_ends_;
const ArenaVector<BasicBlockId>& GetTopologicalSortOrderIndexes() {
return topological_order_indexes_;
ArenaVector<std::pair<uint16_t, bool>>* GetTopologicalSortOrderLoopHeadStack() {
DCHECK(!topological_order_.empty()); // Checking the main array, not the stack.
return &topological_order_loop_head_stack_;
size_t GetMaxNestedLoops() const {
return max_nested_loops_;
bool IsLoopHead(BasicBlockId bb_id) {
return topological_order_loop_ends_[topological_order_indexes_[bb_id]] != 0u;
bool IsConst(int32_t s_reg) const {
return is_constant_v_->IsBitSet(s_reg);
bool IsConst(RegLocation loc) const {
return loc.orig_sreg < 0 ? false : IsConst(loc.orig_sreg);
int32_t ConstantValue(RegLocation loc) const {
return constant_values_[loc.orig_sreg];
int32_t ConstantValue(int32_t s_reg) const {
return constant_values_[s_reg];
* @brief Used to obtain 64-bit value of a pair of ssa registers.
* @param s_reg_low The ssa register representing the low bits.
* @param s_reg_high The ssa register representing the high bits.
* @return Retusn the 64-bit constant value.
int64_t ConstantValueWide(int32_t s_reg_low, int32_t s_reg_high) const {
return (static_cast<int64_t>(constant_values_[s_reg_high]) << 32) |
int64_t ConstantValueWide(RegLocation loc) const {
DCHECK(!loc.high_word); // Do not allow asking for the high partner.
DCHECK_LT(loc.orig_sreg + 1, GetNumSSARegs());
return (static_cast<int64_t>(constant_values_[loc.orig_sreg + 1]) << 32) |
* @brief Used to mark ssa register as being constant.
* @param ssa_reg The ssa register.
* @param value The constant value of ssa register.
void SetConstant(int32_t ssa_reg, int32_t value);
* @brief Used to mark ssa register and its wide counter-part as being constant.
* @param ssa_reg The ssa register.
* @param value The 64-bit constant value of ssa register and its pair.
void SetConstantWide(int32_t ssa_reg, int64_t value);
bool IsConstantNullRef(RegLocation loc) const {
return loc.ref && loc.is_const && (ConstantValue(loc) == 0);
int GetNumSSARegs() const {
return num_ssa_regs_;
void SetNumSSARegs(int new_num) {
* TODO: It's theoretically possible to exceed 32767, though any cases which did
* would be filtered out with current settings. When orig_sreg field is removed
* from RegLocation, expand s_reg_low to handle all possible cases and remove DCHECK().
CHECK_EQ(new_num, static_cast<int16_t>(new_num));
num_ssa_regs_ = new_num;
unsigned int GetNumReachableBlocks() const {
return num_reachable_blocks_;
uint32_t GetUseCount(int sreg) const {
DCHECK_LT(static_cast<size_t>(sreg), use_counts_.size());
return use_counts_[sreg];
uint32_t GetRawUseCount(int sreg) const {
DCHECK_LT(static_cast<size_t>(sreg), raw_use_counts_.size());
return raw_use_counts_[sreg];
int GetSSASubscript(int ssa_reg) const {
DCHECK_LT(static_cast<size_t>(ssa_reg), ssa_subscripts_.size());
return ssa_subscripts_[ssa_reg];
RegLocation GetRawSrc(MIR* mir, int num) {
DCHECK(num < mir->ssa_rep->num_uses);
RegLocation res = reg_location_[mir->ssa_rep->uses[num]];
return res;
RegLocation GetRawDest(MIR* mir) {
DCHECK_GT(mir->ssa_rep->num_defs, 0);
RegLocation res = reg_location_[mir->ssa_rep->defs[0]];
return res;
RegLocation GetDest(MIR* mir) {
RegLocation res = GetRawDest(mir);
return res;
RegLocation GetSrc(MIR* mir, int num) {
RegLocation res = GetRawSrc(mir, num);
return res;
RegLocation GetDestWide(MIR* mir) {
RegLocation res = GetRawDest(mir);
return res;
RegLocation GetSrcWide(MIR* mir, int low) {
RegLocation res = GetRawSrc(mir, low);
return res;
RegLocation GetBadLoc() {
return bad_loc;
int GetMethodSReg() const {
return method_sreg_;
* @brief Used to obtain the number of compiler temporaries being used.
* @return Returns the number of compiler temporaries.
size_t GetNumUsedCompilerTemps() const {
// Assume that the special temps will always be used.
return GetNumNonSpecialCompilerTemps() + max_available_special_compiler_temps_;
* @brief Used to obtain number of bytes needed for special temps.
* @details This space is always needed because temps have special location on stack.
* @return Returns number of bytes for the special temps.
size_t GetNumBytesForSpecialTemps() const;
* @brief Used by backend as a hint for maximum number of bytes for non-special temps.
* @details Returns 4 bytes for each temp because that is the maximum amount needed
* for storing each temp. The BE could be smarter though and allocate a smaller
* spill region.
* @return Returns the maximum number of bytes needed for non-special temps.
size_t GetMaximumBytesForNonSpecialTemps() const {
return GetNumNonSpecialCompilerTemps() * sizeof(uint32_t);
* @brief Used to obtain the number of non-special compiler temporaries being used.
* @return Returns the number of non-special compiler temporaries.
size_t GetNumNonSpecialCompilerTemps() const {
return num_non_special_compiler_temps_;
* @brief Used to set the total number of available non-special compiler temporaries.
* @details Can fail setting the new max if there are more temps being used than the new_max.
* @param new_max The new maximum number of non-special compiler temporaries.
* @return Returns true if the max was set and false if failed to set.
bool SetMaxAvailableNonSpecialCompilerTemps(size_t new_max) {
// Make sure that enough temps still exist for backend and also that the
// new max can still keep around all of the already requested temps.
if (new_max < (GetNumNonSpecialCompilerTemps() + reserved_temps_for_backend_)) {
return false;
} else {
max_available_non_special_compiler_temps_ = new_max;
return true;
* @brief Provides the number of non-special compiler temps available for use by ME.
* @details Even if this returns zero, special compiler temps are guaranteed to be available.
* Additionally, this makes sure to not use any temps reserved for BE only.
* @return Returns the number of available temps.
size_t GetNumAvailableVRTemps();
* @brief Used to obtain the maximum number of compiler temporaries that can be requested.
* @return Returns the maximum number of compiler temporaries, whether used or not.
size_t GetMaxPossibleCompilerTemps() const {
return max_available_special_compiler_temps_ + max_available_non_special_compiler_temps_;
* @brief Used to signal that the compiler temps have been committed.
* @details This should be used once the number of temps can no longer change,
* such as after frame size is committed and cannot be changed.
void CommitCompilerTemps() {
compiler_temps_committed_ = true;
* @brief Used to obtain a new unique compiler temporary.
* @details Two things are done for convenience when allocating a new compiler
* temporary. The ssa register is automatically requested and the information
* about reg location is filled. This helps when the temp is requested post
* ssa initialization, such as when temps are requested by the backend.
* @warning If the temp requested will be used for ME and have multiple versions,
* the sreg provided by the temp will be invalidated on next ssa recalculation.
* @param ct_type Type of compiler temporary requested.
* @param wide Whether we should allocate a wide temporary.
* @return Returns the newly created compiler temporary.
CompilerTemp* GetNewCompilerTemp(CompilerTempType ct_type, bool wide);
* @brief Used to remove last created compiler temporary when it's not needed.
* @param temp the temporary to remove.
void RemoveLastCompilerTemp(CompilerTempType ct_type, bool wide, CompilerTemp* temp);
bool MethodIsLeaf() {
return attributes_ & METHOD_IS_LEAF;
RegLocation GetRegLocation(int index) {
DCHECK((index >= 0) && (index < num_ssa_regs_));
return reg_location_[index];
RegLocation GetMethodLoc() {
return reg_location_[method_sreg_];
bool IsBackEdge(BasicBlock* branch_bb, BasicBlockId target_bb_id) {
DCHECK_NE(target_bb_id, NullBasicBlockId);
DCHECK_LT(target_bb_id, topological_order_indexes_.size());
DCHECK_LT(branch_bb->id, topological_order_indexes_.size());
return topological_order_indexes_[target_bb_id] <= topological_order_indexes_[branch_bb->id];
bool IsSuspendCheckEdge(BasicBlock* branch_bb, BasicBlockId target_bb_id) {
if (!IsBackEdge(branch_bb, target_bb_id)) {
return false;
if (suspend_checks_in_loops_ == nullptr) {
// We didn't run suspend check elimination.
return true;
uint16_t target_depth = GetBasicBlock(target_bb_id)->nesting_depth;
return (suspend_checks_in_loops_[branch_bb->id] & (1u << (target_depth - 1u))) == 0;
void CountBranch(DexOffset target_offset) {
if (target_offset <= current_offset_) {
} else {
int GetBranchCount() {
return backward_branches_ + forward_branches_;
// Is this vreg in the in set?
bool IsInVReg(uint32_t vreg) {
return (vreg >= GetFirstInVR()) && (vreg < GetFirstTempVR());
uint32_t GetNumOfCodeVRs() const {
return current_code_item_->registers_size_;
uint32_t GetNumOfCodeAndTempVRs() const {
// Include all of the possible temps so that no structures overflow when initialized.
return GetNumOfCodeVRs() + GetMaxPossibleCompilerTemps();
uint32_t GetNumOfLocalCodeVRs() const {
// This also refers to the first "in" VR.
return GetNumOfCodeVRs() - current_code_item_->ins_size_;
uint32_t GetNumOfInVRs() const {
return current_code_item_->ins_size_;
uint32_t GetNumOfOutVRs() const {
return current_code_item_->outs_size_;
uint32_t GetFirstInVR() const {
return GetNumOfLocalCodeVRs();
uint32_t GetFirstTempVR() const {
// Temp VRs immediately follow code VRs.
return GetNumOfCodeVRs();
uint32_t GetFirstSpecialTempVR() const {
// Special temps appear first in the ordering before non special temps.
return GetFirstTempVR();
uint32_t GetFirstNonSpecialTempVR() const {
// We always leave space for all the special temps before the non-special ones.
return GetFirstSpecialTempVR() + max_available_special_compiler_temps_;
bool HasTryCatchBlocks() const {
return current_code_item_->tries_size_ != 0;
void DumpCheckStats();
MIR* FindMoveResult(BasicBlock* bb, MIR* mir);
/* Return the base virtual register for a SSA name */
int SRegToVReg(int ssa_reg) const {
return ssa_base_vregs_[ssa_reg];
void VerifyDataflow();
void CheckForDominanceFrontier(BasicBlock* dom_bb, const BasicBlock* succ_bb);
bool EliminateNullChecksGate();
bool EliminateNullChecks(BasicBlock* bb);
void EliminateNullChecksEnd();
void InferTypesStart();
bool InferTypes(BasicBlock* bb);
void InferTypesEnd();
bool EliminateClassInitChecksGate();
bool EliminateClassInitChecks(BasicBlock* bb);
void EliminateClassInitChecksEnd();
bool ApplyGlobalValueNumberingGate();
bool ApplyGlobalValueNumbering(BasicBlock* bb);
void ApplyGlobalValueNumberingEnd();
bool EliminateDeadCodeGate();
bool EliminateDeadCode(BasicBlock* bb);
void EliminateDeadCodeEnd();
void GlobalValueNumberingCleanup();
bool EliminateSuspendChecksGate();
bool EliminateSuspendChecks(BasicBlock* bb);
uint16_t GetGvnIFieldId(MIR* mir) const {
DCHECK_LT(mir->meta.ifield_lowering_info, ifield_lowering_infos_.size());
DCHECK(temp_.gvn.ifield_ids != nullptr);
return temp_.gvn.ifield_ids[mir->meta.ifield_lowering_info];
uint16_t GetGvnSFieldId(MIR* mir) const {
DCHECK_LT(mir->meta.sfield_lowering_info, sfield_lowering_infos_.size());
DCHECK(temp_.gvn.sfield_ids != nullptr);
return temp_.gvn.sfield_ids[mir->meta.sfield_lowering_info];
bool PuntToInterpreter() {
return punt_to_interpreter_;
void SetPuntToInterpreter(bool val);
void DisassembleExtendedInstr(const MIR* mir, std::string* decoded_mir);
char* GetDalvikDisassembly(const MIR* mir);
void ReplaceSpecialChars(std::string& str);
std::string GetSSAName(int ssa_reg);
std::string GetSSANameWithConst(int ssa_reg, bool singles_only);
void GetBlockName(BasicBlock* bb, char* name);
const char* GetShortyFromMethodReference(const MethodReference& target_method);
void DumpMIRGraph();
CallInfo* NewMemCallInfo(BasicBlock* bb, MIR* mir, InvokeType type, bool is_range);
BasicBlock* NewMemBB(BBType block_type, int block_id);
MIR* NewMIR();
MIR* AdvanceMIR(BasicBlock** p_bb, MIR* mir);
BasicBlock* NextDominatedBlock(BasicBlock* bb);
bool LayoutBlocks(BasicBlock* bb);
void ComputeTopologicalSortOrder();
BasicBlock* CreateNewBB(BBType block_type);
bool InlineSpecialMethodsGate();
void InlineSpecialMethodsStart();
void InlineSpecialMethods(BasicBlock* bb);
void InlineSpecialMethodsEnd();
* @brief Perform the initial preparation for the Method Uses.
void InitializeMethodUses();
* @brief Perform the initial preparation for the Constant Propagation.
void InitializeConstantPropagation();
* @brief Perform the initial preparation for the SSA Transformation.
void SSATransformationStart();
* @brief Insert a the operands for the Phi nodes.
* @param bb the considered BasicBlock.
* @return true
bool InsertPhiNodeOperands(BasicBlock* bb);
* @brief Perform the cleanup after the SSA Transformation.
void SSATransformationEnd();
* @brief Perform constant propagation on a BasicBlock.
* @param bb the considered BasicBlock.
void DoConstantPropagation(BasicBlock* bb);
* @brief Get use count weight for a given block.
* @param bb the BasicBlock.
uint32_t GetUseCountWeight(BasicBlock* bb) const;
* @brief Count the uses in the BasicBlock
* @param bb the BasicBlock
void CountUses(BasicBlock* bb);
static uint64_t GetDataFlowAttributes(Instruction::Code opcode);
static uint64_t GetDataFlowAttributes(MIR* mir);
* @brief Combine BasicBlocks
* @param the BasicBlock we are considering
void CombineBlocks(BasicBlock* bb);
void ClearAllVisitedFlags();
void AllocateSSAUseData(MIR *mir, int num_uses);
void AllocateSSADefData(MIR *mir, int num_defs);
void CalculateBasicBlockInformation(const PassManager* const post_opt);
void ComputeDFSOrders();
void ComputeDefBlockMatrix();
void ComputeDominators();
void CompilerInitializeSSAConversion();
virtual void InitializeBasicBlockDataFlow();
void FindPhiNodeBlocks();
void DoDFSPreOrderSSARename(BasicBlock* block);
bool DfsOrdersUpToDate() const {
return dfs_orders_up_to_date_;
bool DominationUpToDate() const {
return domination_up_to_date_;
bool MirSsaRepUpToDate() const {
return mir_ssa_rep_up_to_date_;
bool TopologicalOrderUpToDate() const {
return topological_order_up_to_date_;
* IsDebugBuild sanity check: keep track of the Dex PCs for catch entries so that later on
* we can verify that all catch entries have native PC entries.
std::set<uint32_t> catches_;
// TODO: make these private.
RegLocation* reg_location_; // Map SSA names to location.
ArenaSafeMap<unsigned int, unsigned int> block_id_map_; // Block collapse lookup cache.
static const char* extended_mir_op_names_[kMirOpLast - kMirOpFirst];
void HandleSSADef(int* defs, int dalvik_reg, int reg_index);
int FindCommonParent(int block1, int block2);
void ComputeSuccLineIn(ArenaBitVector* dest, const ArenaBitVector* src1,
const ArenaBitVector* src2);
void HandleLiveInUse(ArenaBitVector* use_v, ArenaBitVector* def_v,
ArenaBitVector* live_in_v, int dalvik_reg_id);
void HandleDef(ArenaBitVector* def_v, int dalvik_reg_id);
void HandleExtended(ArenaBitVector* use_v, ArenaBitVector* def_v,
ArenaBitVector* live_in_v,
const MIR::DecodedInstruction& d_insn);
bool DoSSAConversion(BasicBlock* bb);
int ParseInsn(const uint16_t* code_ptr, MIR::DecodedInstruction* decoded_instruction);
bool ContentIsInsn(const uint16_t* code_ptr);
BasicBlock* SplitBlock(DexOffset code_offset, BasicBlock* orig_block,
BasicBlock** immed_pred_block_p);
BasicBlock* FindBlock(DexOffset code_offset, bool create, BasicBlock** immed_pred_block_p,
ScopedArenaVector<uint16_t>* dex_pc_to_block_map);
void ProcessTryCatchBlocks(ScopedArenaVector<uint16_t>* dex_pc_to_block_map);
bool IsBadMonitorExitCatch(NarrowDexOffset monitor_exit_offset, NarrowDexOffset catch_offset);
BasicBlock* ProcessCanBranch(BasicBlock* cur_block, MIR* insn, DexOffset cur_offset, int width,
int flags, const uint16_t* code_ptr, const uint16_t* code_end,
ScopedArenaVector<uint16_t>* dex_pc_to_block_map);
BasicBlock* ProcessCanSwitch(BasicBlock* cur_block, MIR* insn, DexOffset cur_offset, int width,
int flags,
ScopedArenaVector<uint16_t>* dex_pc_to_block_map);
BasicBlock* ProcessCanThrow(BasicBlock* cur_block, MIR* insn, DexOffset cur_offset, int width,
int flags, ArenaBitVector* try_block_addr, const uint16_t* code_ptr,
const uint16_t* code_end,
ScopedArenaVector<uint16_t>* dex_pc_to_block_map);
int AddNewSReg(int v_reg);
void HandleSSAUse(int* uses, int dalvik_reg, int reg_index);
void DataFlowSSAFormat35C(MIR* mir);
void DataFlowSSAFormat3RC(MIR* mir);
void DataFlowSSAFormatExtended(MIR* mir);
bool FindLocalLiveIn(BasicBlock* bb);
bool VerifyPredInfo(BasicBlock* bb);
BasicBlock* NeedsVisit(BasicBlock* bb);
BasicBlock* NextUnvisitedSuccessor(BasicBlock* bb);
void MarkPreOrder(BasicBlock* bb);
void RecordDFSOrders(BasicBlock* bb);
void ComputeDomPostOrderTraversal(BasicBlock* bb);
int GetSSAUseCount(int s_reg);
bool BasicBlockOpt(BasicBlock* bb);
void MultiplyAddOpt(BasicBlock* bb);
* @brief Check whether the given MIR is possible to throw an exception.
* @param mir The mir to check.
* @return Returns 'true' if the given MIR might throw an exception.
bool CanThrow(MIR* mir) const;
* @brief Combine multiply and add/sub MIRs into corresponding extended MAC MIR.
* @param mul_mir The multiply MIR to be combined.
* @param add_mir The add/sub MIR to be combined.
* @param mul_is_first_addend 'true' if multiply product is the first addend of add operation.
* @param is_wide 'true' if the operations are long type.
* @param is_sub 'true' if it is a multiply-subtract operation.
void CombineMultiplyAdd(MIR* mul_mir, MIR* add_mir, bool mul_is_first_addend,
bool is_wide, bool is_sub);
* @brief Check whether the first MIR anti-depends on the second MIR.
* @details To check whether one of first MIR's uses of vregs is redefined by the second MIR,
* i.e. there is a write-after-read dependency.
* @param first The first MIR.
* @param second The second MIR.
* @param Returns true if there is a write-after-read dependency.
bool HasAntiDependency(MIR* first, MIR* second);
bool BuildExtendedBBList(class BasicBlock* bb);
bool FillDefBlockMatrix(BasicBlock* bb);
void InitializeDominationInfo(BasicBlock* bb);
bool ComputeblockIDom(BasicBlock* bb);
bool ComputeBlockDominators(BasicBlock* bb);
bool SetDominators(BasicBlock* bb);
bool ComputeBlockLiveIns(BasicBlock* bb);
bool ComputeDominanceFrontier(BasicBlock* bb);
void CountChecks(BasicBlock* bb);
void AnalyzeBlock(BasicBlock* bb, struct MethodStats* stats);
bool ComputeSkipCompilation(struct MethodStats* stats, bool skip_default,
std::string* skip_message);
CompilationUnit* const cu_;
ArenaVector<int> ssa_base_vregs_;
ArenaVector<int> ssa_subscripts_;
// Map original Dalvik virtual reg i to the current SSA name.
int32_t* vreg_to_ssa_map_; // length == method->registers_size
int* ssa_last_defs_; // length == method->registers_size
ArenaBitVector* is_constant_v_; // length == num_ssa_reg
int* constant_values_; // length == num_ssa_reg
// Use counts of ssa names.
ArenaVector<uint32_t> use_counts_; // Weighted by nesting depth
ArenaVector<uint32_t> raw_use_counts_; // Not weighted
unsigned int num_reachable_blocks_;
unsigned int max_num_reachable_blocks_;
bool dfs_orders_up_to_date_;
bool domination_up_to_date_;
bool mir_ssa_rep_up_to_date_;
bool topological_order_up_to_date_;
ArenaVector<BasicBlockId> dfs_order_;
ArenaVector<BasicBlockId> dfs_post_order_;
ArenaVector<BasicBlockId> dom_post_order_traversal_;
ArenaVector<BasicBlockId> topological_order_;
// Indexes in topological_order_ need to be only as big as the BasicBlockId.
static_assert(sizeof(BasicBlockId) == sizeof(uint16_t), "Assuming 16 bit BasicBlockId");
// For each loop head, remember the past-the-end index of the end of the loop. 0 if not loop head.
ArenaVector<uint16_t> topological_order_loop_ends_;
// Map BB ids to topological_order_ indexes. 0xffff if not included (hidden or null block).
ArenaVector<uint16_t> topological_order_indexes_;
// Stack of the loop head indexes and recalculation flags for RepeatingTopologicalSortIterator.
ArenaVector<std::pair<uint16_t, bool>> topological_order_loop_head_stack_;
size_t max_nested_loops_;
int* i_dom_list_;
std::unique_ptr<ScopedArenaAllocator> temp_scoped_alloc_;
// Union of temporaries used by different passes.
union {
// Class init check elimination.
struct {
size_t num_class_bits; // 2 bits per class: class initialized and class in dex cache.
ArenaBitVector* work_classes_to_check;
ArenaBitVector** ending_classes_to_check_matrix; // num_blocks_ x num_class_bits.
uint16_t* indexes;
} cice;
// Null check elimination.
struct {
size_t num_vregs;
ArenaBitVector* work_vregs_to_check;
ArenaBitVector** ending_vregs_to_check_matrix; // num_blocks_ x num_vregs.
} nce;
// Special method inlining.
struct {
size_t num_indexes;
ArenaBitVector* processed_indexes;
uint16_t* lowering_infos;
} smi;
// SSA transformation.
struct {
size_t num_vregs;
ArenaBitVector* work_live_vregs;
ArenaBitVector** def_block_matrix; // num_vregs x num_blocks_.
ArenaBitVector** phi_node_blocks; // num_vregs x num_blocks_.
TypeInference* ti;
} ssa;
// Global value numbering.
struct {
GlobalValueNumbering* gvn;
uint16_t* ifield_ids; // Part of GVN/LVN but cached here for LVN to avoid recalculation.
uint16_t* sfield_ids; // Ditto.
GvnDeadCodeElimination* dce;
} gvn;
} temp_;
static const int kInvalidEntry = -1;
ArenaVector<BasicBlock*> block_list_;
ArenaBitVector* try_block_addr_;
BasicBlock* entry_block_;
BasicBlock* exit_block_;
const DexFile::CodeItem* current_code_item_;
ArenaVector<DexCompilationUnit*> m_units_; // List of methods included in this graph
typedef std::pair<int, int> MIRLocation; // Insert point, (m_unit_ index, offset)
ArenaVector<MIRLocation> method_stack_; // Include stack
int current_method_;
DexOffset current_offset_; // Offset in code units
int def_count_; // Used to estimate size of ssa name storage.
int* opcode_count_; // Dex opcode coverage stats.
int num_ssa_regs_; // Number of names following SSA transformation.
ArenaVector<BasicBlockId> extended_basic_blocks_; // Heads of block "traces".
int method_sreg_;
unsigned int attributes_;
Checkstats* checkstats_;
ArenaAllocator* const arena_;
int backward_branches_;
int forward_branches_;
size_t num_non_special_compiler_temps_; // Keeps track of allocated non-special compiler temps. These are VRs that are in compiler temp region on stack.
size_t max_available_non_special_compiler_temps_; // Keeps track of maximum available non-special temps.
size_t max_available_special_compiler_temps_; // Keeps track of maximum available special temps.
bool requested_backend_temp_; // Keeps track whether BE temps have been requested.
size_t reserved_temps_for_backend_; // Keeps track of the remaining temps that are reserved for BE.
bool compiler_temps_committed_; // Keeps track whether number of temps has been frozen (for example post frame size calculation).
bool punt_to_interpreter_; // Difficult or not worthwhile - just interpret.
uint64_t merged_df_flags_;
ArenaVector<MirIFieldLoweringInfo> ifield_lowering_infos_;
ArenaVector<MirSFieldLoweringInfo> sfield_lowering_infos_;
ArenaVector<MirMethodLoweringInfo> method_lowering_infos_;
// In the suspend check elimination pass we determine for each basic block and enclosing
// loop whether there's guaranteed to be a suspend check on the path from the loop head
// to this block. If so, we can eliminate the back-edge suspend check.
// The bb->id is index into suspend_checks_in_loops_ and the loop head's depth is bit index
// in a suspend_checks_in_loops_[bb->id].
uint32_t* suspend_checks_in_loops_;
static const uint64_t oat_data_flow_attributes_[kMirOpLast];
friend class MirOptimizationTest;
friend class ClassInitCheckEliminationTest;
friend class SuspendCheckEliminationTest;
friend class NullCheckEliminationTest;
friend class GlobalValueNumberingTest;
friend class GvnDeadCodeEliminationTest;
friend class LocalValueNumberingTest;
friend class TopologicalSortOrderTest;
friend class TypeInferenceTest;
friend class QuickCFITest;
friend class QuickAssembleX86TestBase;
} // namespace art