mir_graph.h revision 0b1191cfece83f6f8d4101575a06555a2d13387a
1/*
2 * Copyright (C) 2013 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#ifndef ART_COMPILER_DEX_MIR_GRAPH_H_
18#define ART_COMPILER_DEX_MIR_GRAPH_H_
19
20#include "dex_file.h"
21#include "dex_instruction.h"
22#include "compiler_ir.h"
23#include "arena_bit_vector.h"
24#include "growable_array.h"
25
26namespace art {
27
28enum InstructionAnalysisAttributePos {
29  kUninterestingOp = 0,
30  kArithmeticOp,
31  kFPOp,
32  kSingleOp,
33  kDoubleOp,
34  kIntOp,
35  kLongOp,
36  kBranchOp,
37  kInvokeOp,
38  kArrayOp,
39  kHeavyweightOp,
40  kSimpleConstOp,
41  kMoveOp,
42  kSwitch
43};
44
45#define AN_NONE (1 << kUninterestingOp)
46#define AN_MATH (1 << kArithmeticOp)
47#define AN_FP (1 << kFPOp)
48#define AN_LONG (1 << kLongOp)
49#define AN_INT (1 << kIntOp)
50#define AN_SINGLE (1 << kSingleOp)
51#define AN_DOUBLE (1 << kDoubleOp)
52#define AN_FLOATMATH (1 << kFPOp)
53#define AN_BRANCH (1 << kBranchOp)
54#define AN_INVOKE (1 << kInvokeOp)
55#define AN_ARRAYOP (1 << kArrayOp)
56#define AN_HEAVYWEIGHT (1 << kHeavyweightOp)
57#define AN_SIMPLECONST (1 << kSimpleConstOp)
58#define AN_MOVE (1 << kMoveOp)
59#define AN_SWITCH (1 << kSwitch)
60#define AN_COMPUTATIONAL (AN_MATH | AN_ARRAYOP | AN_MOVE | AN_SIMPLECONST)
61
62enum DataFlowAttributePos {
63  kUA = 0,
64  kUB,
65  kUC,
66  kAWide,
67  kBWide,
68  kCWide,
69  kDA,
70  kIsMove,
71  kSetsConst,
72  kFormat35c,
73  kFormat3rc,
74  kNullCheckSrc0,        // Null check of uses[0].
75  kNullCheckSrc1,        // Null check of uses[1].
76  kNullCheckSrc2,        // Null check of uses[2].
77  kNullCheckOut0,        // Null check out outgoing arg0.
78  kDstNonNull,           // May assume dst is non-null.
79  kRetNonNull,           // May assume retval is non-null.
80  kNullTransferSrc0,     // Object copy src[0] -> dst.
81  kNullTransferSrcN,     // Phi null check state transfer.
82  kRangeCheckSrc1,       // Range check of uses[1].
83  kRangeCheckSrc2,       // Range check of uses[2].
84  kRangeCheckSrc3,       // Range check of uses[3].
85  kFPA,
86  kFPB,
87  kFPC,
88  kCoreA,
89  kCoreB,
90  kCoreC,
91  kRefA,
92  kRefB,
93  kRefC,
94  kUsesMethodStar,       // Implicit use of Method*.
95};
96
97#define DF_NOP                  0
98#define DF_UA                   (1 << kUA)
99#define DF_UB                   (1 << kUB)
100#define DF_UC                   (1 << kUC)
101#define DF_A_WIDE               (1 << kAWide)
102#define DF_B_WIDE               (1 << kBWide)
103#define DF_C_WIDE               (1 << kCWide)
104#define DF_DA                   (1 << kDA)
105#define DF_IS_MOVE              (1 << kIsMove)
106#define DF_SETS_CONST           (1 << kSetsConst)
107#define DF_FORMAT_35C           (1 << kFormat35c)
108#define DF_FORMAT_3RC           (1 << kFormat3rc)
109#define DF_NULL_CHK_0           (1 << kNullCheckSrc0)
110#define DF_NULL_CHK_1           (1 << kNullCheckSrc1)
111#define DF_NULL_CHK_2           (1 << kNullCheckSrc2)
112#define DF_NULL_CHK_OUT0        (1 << kNullCheckOut0)
113#define DF_NON_NULL_DST         (1 << kDstNonNull)
114#define DF_NON_NULL_RET         (1 << kRetNonNull)
115#define DF_NULL_TRANSFER_0      (1 << kNullTransferSrc0)
116#define DF_NULL_TRANSFER_N      (1 << kNullTransferSrcN)
117#define DF_RANGE_CHK_1          (1 << kRangeCheckSrc1)
118#define DF_RANGE_CHK_2          (1 << kRangeCheckSrc2)
119#define DF_RANGE_CHK_3          (1 << kRangeCheckSrc3)
120#define DF_FP_A                 (1 << kFPA)
121#define DF_FP_B                 (1 << kFPB)
122#define DF_FP_C                 (1 << kFPC)
123#define DF_CORE_A               (1 << kCoreA)
124#define DF_CORE_B               (1 << kCoreB)
125#define DF_CORE_C               (1 << kCoreC)
126#define DF_REF_A                (1 << kRefA)
127#define DF_REF_B                (1 << kRefB)
128#define DF_REF_C                (1 << kRefC)
129#define DF_UMS                  (1 << kUsesMethodStar)
130
131#define DF_HAS_USES             (DF_UA | DF_UB | DF_UC)
132
133#define DF_HAS_DEFS             (DF_DA)
134
135#define DF_HAS_NULL_CHKS        (DF_NULL_CHK_0 | \
136                                 DF_NULL_CHK_1 | \
137                                 DF_NULL_CHK_2 | \
138                                 DF_NULL_CHK_OUT0)
139
140#define DF_HAS_RANGE_CHKS       (DF_RANGE_CHK_1 | \
141                                 DF_RANGE_CHK_2 | \
142                                 DF_RANGE_CHK_3)
143
144#define DF_HAS_NR_CHKS          (DF_HAS_NULL_CHKS | \
145                                 DF_HAS_RANGE_CHKS)
146
147#define DF_A_IS_REG             (DF_UA | DF_DA)
148#define DF_B_IS_REG             (DF_UB)
149#define DF_C_IS_REG             (DF_UC)
150#define DF_IS_GETTER_OR_SETTER  (DF_IS_GETTER | DF_IS_SETTER)
151#define DF_USES_FP              (DF_FP_A | DF_FP_B | DF_FP_C)
152#define DF_NULL_TRANSFER        (DF_NULL_TRANSFER_0 | DF_NULL_TRANSFER_N)
153enum OatMethodAttributes {
154  kIsLeaf,            // Method is leaf.
155  kHasLoop,           // Method contains simple loop.
156};
157
158#define METHOD_IS_LEAF          (1 << kIsLeaf)
159#define METHOD_HAS_LOOP         (1 << kHasLoop)
160
161// Minimum field size to contain Dalvik v_reg number.
162#define VREG_NUM_WIDTH 16
163
164#define INVALID_SREG (-1)
165#define INVALID_VREG (0xFFFFU)
166#define INVALID_REG (0xFF)
167#define INVALID_OFFSET (0xDEADF00FU)
168
169/* SSA encodings for special registers */
170#define SSA_METHOD_BASEREG (-2)
171/* First compiler temp basereg, grows smaller */
172#define SSA_CTEMP_BASEREG (SSA_METHOD_BASEREG - 1)
173
174#define MIR_IGNORE_NULL_CHECK           (1 << kMIRIgnoreNullCheck)
175#define MIR_NULL_CHECK_ONLY             (1 << kMIRNullCheckOnly)
176#define MIR_IGNORE_RANGE_CHECK          (1 << kMIRIgnoreRangeCheck)
177#define MIR_RANGE_CHECK_ONLY            (1 << kMIRRangeCheckOnly)
178#define MIR_INLINED                     (1 << kMIRInlined)
179#define MIR_INLINED_PRED                (1 << kMIRInlinedPred)
180#define MIR_CALLEE                      (1 << kMIRCallee)
181#define MIR_IGNORE_SUSPEND_CHECK        (1 << kMIRIgnoreSuspendCheck)
182#define MIR_DUP                         (1 << kMIRDup)
183
184#define BLOCK_NAME_LEN 80
185
186typedef uint16_t BasicBlockId;
187static const BasicBlockId NullBasicBlockId = 0;
188
189/*
190 * In general, vreg/sreg describe Dalvik registers that originated with dx.  However,
191 * it is useful to have compiler-generated temporary registers and have them treated
192 * in the same manner as dx-generated virtual registers.  This struct records the SSA
193 * name of compiler-introduced temporaries.
194 */
195struct CompilerTemp {
196  int32_t s_reg;
197};
198
199// When debug option enabled, records effectiveness of null and range check elimination.
200struct Checkstats {
201  int32_t null_checks;
202  int32_t null_checks_eliminated;
203  int32_t range_checks;
204  int32_t range_checks_eliminated;
205};
206
207// Dataflow attributes of a basic block.
208struct BasicBlockDataFlow {
209  ArenaBitVector* use_v;
210  ArenaBitVector* def_v;
211  ArenaBitVector* live_in_v;
212  ArenaBitVector* phi_v;
213  int32_t* vreg_to_ssa_map;
214  ArenaBitVector* ending_null_check_v;
215};
216
217/*
218 * Normalized use/def for a MIR operation using SSA names rather than vregs.  Note that
219 * uses/defs retain the Dalvik convention that long operations operate on a pair of 32-bit
220 * vregs.  For example, "ADD_LONG v0, v2, v3" would have 2 defs (v0/v1) and 4 uses (v2/v3, v4/v5).
221 * Following SSA renaming, this is the primary struct used by code generators to locate
222 * operand and result registers.  This is a somewhat confusing and unhelpful convention that
223 * we may want to revisit in the future.
224 */
225struct SSARepresentation {
226  int16_t num_uses;
227  int16_t num_defs;
228  int32_t* uses;
229  bool* fp_use;
230  int32_t* defs;
231  bool* fp_def;
232};
233
234/*
235 * The Midlevel Intermediate Representation node, which may be largely considered a
236 * wrapper around a Dalvik byte code.
237 */
238struct MIR {
239  /*
240   * TODO: remove embedded DecodedInstruction to save space, keeping only opcode.  Recover
241   * additional fields on as-needed basis.  Question: how to support MIR Pseudo-ops; probably
242   * need to carry aux data pointer.
243   */
244  DecodedInstruction dalvikInsn;
245  uint16_t width;                 // Note: width can include switch table or fill array data.
246  NarrowDexOffset offset;         // Offset of the instruction in code units.
247  uint16_t optimization_flags;
248  int16_t m_unit_index;           // From which method was this MIR included
249  MIR* next;
250  SSARepresentation* ssa_rep;
251  union {
252    // Incoming edges for phi node.
253    BasicBlockId* phi_incoming;
254    // Establish link between two halves of throwing instructions.
255    MIR* throw_insn;
256  } meta;
257};
258
259struct SuccessorBlockInfo;
260
261struct BasicBlock {
262  BasicBlockId id;
263  BasicBlockId dfs_id;
264  NarrowDexOffset start_offset;     // Offset in code units.
265  BasicBlockId fall_through;
266  BasicBlockId taken;
267  BasicBlockId i_dom;               // Immediate dominator.
268  uint16_t nesting_depth;
269  BBType block_type:4;
270  BlockListType successor_block_list_type:4;
271  bool visited:1;
272  bool hidden:1;
273  bool catch_entry:1;
274  bool explicit_throw:1;
275  bool conditional_branch:1;
276  bool terminated_by_return:1;        // Block ends with a Dalvik return opcode.
277  bool dominates_return:1;            // Is a member of return extended basic block.
278  MIR* first_mir_insn;
279  MIR* last_mir_insn;
280  BasicBlockDataFlow* data_flow_info;
281  ArenaBitVector* dominators;
282  ArenaBitVector* i_dominated;      // Set nodes being immediately dominated.
283  ArenaBitVector* dom_frontier;     // Dominance frontier.
284  GrowableArray<BasicBlockId>* predecessors;
285  GrowableArray<SuccessorBlockInfo*>* successor_blocks;
286};
287
288/*
289 * The "blocks" field in "successor_block_list" points to an array of elements with the type
290 * "SuccessorBlockInfo".  For catch blocks, key is type index for the exception.  For swtich
291 * blocks, key is the case value.
292 */
293struct SuccessorBlockInfo {
294  BasicBlockId block;
295  int key;
296};
297
298/*
299 * Whereas a SSA name describes a definition of a Dalvik vreg, the RegLocation describes
300 * the type of an SSA name (and, can also be used by code generators to record where the
301 * value is located (i.e. - physical register, frame, spill, etc.).  For each SSA name (SReg)
302 * there is a RegLocation.
303 * A note on SSA names:
304 *   o SSA names for Dalvik vRegs v0..vN will be assigned 0..N.  These represent the "vN_0"
305 *     names.  Negative SSA names represent special values not present in the Dalvik byte code.
306 *     For example, SSA name -1 represents an invalid SSA name, and SSA name -2 represents the
307 *     the Method pointer.  SSA names < -2 are reserved for future use.
308 *   o The vN_0 names for non-argument Dalvik should in practice never be used (as they would
309 *     represent the read of an undefined local variable).  The first definition of the
310 *     underlying Dalvik vReg will result in a vN_1 name.
311 *
312 * FIXME: The orig_sreg field was added as a workaround for llvm bitcode generation.  With
313 * the latest restructuring, we should be able to remove it and rely on s_reg_low throughout.
314 */
315struct RegLocation {
316  RegLocationType location:3;
317  unsigned wide:1;
318  unsigned defined:1;   // Do we know the type?
319  unsigned is_const:1;  // Constant, value in mir_graph->constant_values[].
320  unsigned fp:1;        // Floating point?
321  unsigned core:1;      // Non-floating point?
322  unsigned ref:1;       // Something GC cares about.
323  unsigned high_word:1;  // High word of pair?
324  unsigned home:1;      // Does this represent the home location?
325  uint8_t low_reg;      // First physical register.
326  uint8_t high_reg;     // 2nd physical register (if wide).
327  int16_t s_reg_low;    // SSA name for low Dalvik word.
328  int16_t orig_sreg;    // TODO: remove after Bitcode gen complete
329                        // and consolidate usage w/ s_reg_low.
330};
331
332/*
333 * Collection of information describing an invoke, and the destination of
334 * the subsequent MOVE_RESULT (if applicable).  Collected as a unit to enable
335 * more efficient invoke code generation.
336 */
337struct CallInfo {
338  int num_arg_words;    // Note: word count, not arg count.
339  RegLocation* args;    // One for each word of arguments.
340  RegLocation result;   // Eventual target of MOVE_RESULT.
341  int opt_flags;
342  InvokeType type;
343  uint32_t dex_idx;
344  uint32_t index;       // Method idx for invokes, type idx for FilledNewArray.
345  uintptr_t direct_code;
346  uintptr_t direct_method;
347  RegLocation target;    // Target of following move_result.
348  bool skip_this;
349  bool is_range;
350  DexOffset offset;      // Offset in code units.
351};
352
353
354const RegLocation bad_loc = {kLocDalvikFrame, 0, 0, 0, 0, 0, 0, 0, 0,
355                             INVALID_REG, INVALID_REG, INVALID_SREG, INVALID_SREG};
356
357class MIRGraph {
358 public:
359  MIRGraph(CompilationUnit* cu, ArenaAllocator* arena);
360  ~MIRGraph();
361
362  /*
363   * Examine the graph to determine whether it's worthwile to spend the time compiling
364   * this method.
365   */
366  bool SkipCompilation(Runtime::CompilerFilter compiler_filter);
367
368  /*
369   * Parse dex method and add MIR at current insert point.  Returns id (which is
370   * actually the index of the method in the m_units_ array).
371   */
372  void InlineMethod(const DexFile::CodeItem* code_item, uint32_t access_flags,
373                    InvokeType invoke_type, uint16_t class_def_idx,
374                    uint32_t method_idx, jobject class_loader, const DexFile& dex_file);
375
376  /* Find existing block */
377  BasicBlock* FindBlock(DexOffset code_offset) {
378    return FindBlock(code_offset, false, false, NULL);
379  }
380
381  const uint16_t* GetCurrentInsns() const {
382    return current_code_item_->insns_;
383  }
384
385  const uint16_t* GetInsns(int m_unit_index) const {
386    return m_units_[m_unit_index]->GetCodeItem()->insns_;
387  }
388
389  int GetNumBlocks() const {
390    return num_blocks_;
391  }
392
393  size_t GetNumDalvikInsns() const {
394    return cu_->code_item->insns_size_in_code_units_;
395  }
396
397  ArenaBitVector* GetTryBlockAddr() const {
398    return try_block_addr_;
399  }
400
401  BasicBlock* GetEntryBlock() const {
402    return entry_block_;
403  }
404
405  BasicBlock* GetExitBlock() const {
406    return exit_block_;
407  }
408
409  BasicBlock* GetBasicBlock(int block_id) const {
410    return (block_id == NullBasicBlockId) ? NULL : block_list_.Get(block_id);
411  }
412
413  size_t GetBasicBlockListCount() const {
414    return block_list_.Size();
415  }
416
417  GrowableArray<BasicBlock*>* GetBlockList() {
418    return &block_list_;
419  }
420
421  GrowableArray<BasicBlockId>* GetDfsOrder() {
422    return dfs_order_;
423  }
424
425  GrowableArray<BasicBlockId>* GetDfsPostOrder() {
426    return dfs_post_order_;
427  }
428
429  GrowableArray<BasicBlockId>* GetDomPostOrder() {
430    return dom_post_order_traversal_;
431  }
432
433  int GetDefCount() const {
434    return def_count_;
435  }
436
437  ArenaAllocator* GetArena() {
438    return arena_;
439  }
440
441  void EnableOpcodeCounting() {
442    opcode_count_ = static_cast<int*>(arena_->Alloc(kNumPackedOpcodes * sizeof(int),
443                                                    ArenaAllocator::kAllocMisc));
444  }
445
446  void ShowOpcodeStats();
447
448  DexCompilationUnit* GetCurrentDexCompilationUnit() const {
449    return m_units_[current_method_];
450  }
451
452  void DumpCFG(const char* dir_prefix, bool all_blocks);
453
454  void BuildRegLocations();
455
456  void DumpRegLocTable(RegLocation* table, int count);
457
458  void BasicBlockOptimization();
459
460  bool IsConst(int32_t s_reg) const {
461    return is_constant_v_->IsBitSet(s_reg);
462  }
463
464  bool IsConst(RegLocation loc) const {
465    return (IsConst(loc.orig_sreg));
466  }
467
468  int32_t ConstantValue(RegLocation loc) const {
469    DCHECK(IsConst(loc));
470    return constant_values_[loc.orig_sreg];
471  }
472
473  int32_t ConstantValue(int32_t s_reg) const {
474    DCHECK(IsConst(s_reg));
475    return constant_values_[s_reg];
476  }
477
478  int64_t ConstantValueWide(RegLocation loc) const {
479    DCHECK(IsConst(loc));
480    return (static_cast<int64_t>(constant_values_[loc.orig_sreg + 1]) << 32) |
481        Low32Bits(static_cast<int64_t>(constant_values_[loc.orig_sreg]));
482  }
483
484  bool IsConstantNullRef(RegLocation loc) const {
485    return loc.ref && loc.is_const && (ConstantValue(loc) == 0);
486  }
487
488  int GetNumSSARegs() const {
489    return num_ssa_regs_;
490  }
491
492  void SetNumSSARegs(int new_num) {
493     /*
494      * TODO: It's theoretically possible to exceed 32767, though any cases which did
495      * would be filtered out with current settings.  When orig_sreg field is removed
496      * from RegLocation, expand s_reg_low to handle all possible cases and remove DCHECK().
497      */
498    DCHECK_EQ(new_num, static_cast<int16_t>(new_num));
499    num_ssa_regs_ = new_num;
500  }
501
502  unsigned int GetNumReachableBlocks() const {
503    return num_reachable_blocks_;
504  }
505
506  int GetUseCount(int vreg) const {
507    return use_counts_.Get(vreg);
508  }
509
510  int GetRawUseCount(int vreg) const {
511    return raw_use_counts_.Get(vreg);
512  }
513
514  int GetSSASubscript(int ssa_reg) const {
515    return ssa_subscripts_->Get(ssa_reg);
516  }
517
518  RegLocation GetRawSrc(MIR* mir, int num) {
519    DCHECK(num < mir->ssa_rep->num_uses);
520    RegLocation res = reg_location_[mir->ssa_rep->uses[num]];
521    return res;
522  }
523
524  RegLocation GetRawDest(MIR* mir) {
525    DCHECK_GT(mir->ssa_rep->num_defs, 0);
526    RegLocation res = reg_location_[mir->ssa_rep->defs[0]];
527    return res;
528  }
529
530  RegLocation GetDest(MIR* mir) {
531    RegLocation res = GetRawDest(mir);
532    DCHECK(!res.wide);
533    return res;
534  }
535
536  RegLocation GetSrc(MIR* mir, int num) {
537    RegLocation res = GetRawSrc(mir, num);
538    DCHECK(!res.wide);
539    return res;
540  }
541
542  RegLocation GetDestWide(MIR* mir) {
543    RegLocation res = GetRawDest(mir);
544    DCHECK(res.wide);
545    return res;
546  }
547
548  RegLocation GetSrcWide(MIR* mir, int low) {
549    RegLocation res = GetRawSrc(mir, low);
550    DCHECK(res.wide);
551    return res;
552  }
553
554  RegLocation GetBadLoc() {
555    return bad_loc;
556  }
557
558  int GetMethodSReg() {
559    return method_sreg_;
560  }
561
562  bool MethodIsLeaf() {
563    return attributes_ & METHOD_IS_LEAF;
564  }
565
566  RegLocation GetRegLocation(int index) {
567    DCHECK((index >= 0) && (index > num_ssa_regs_));
568    return reg_location_[index];
569  }
570
571  RegLocation GetMethodLoc() {
572    return reg_location_[method_sreg_];
573  }
574
575  bool IsSpecialCase() {
576    return special_case_ != kNoHandler;
577  }
578
579  SpecialCaseHandler GetSpecialCase() {
580    return special_case_;
581  }
582
583  bool IsBackedge(BasicBlock* branch_bb, BasicBlockId target_bb_id) {
584    return ((target_bb_id != NullBasicBlockId) &&
585            (GetBasicBlock(target_bb_id)->start_offset <= branch_bb->start_offset));
586  }
587
588  bool IsBackwardsBranch(BasicBlock* branch_bb) {
589    return IsBackedge(branch_bb, branch_bb->taken) || IsBackedge(branch_bb, branch_bb->fall_through);
590  }
591
592  void CountBranch(DexOffset target_offset) {
593    if (target_offset <= current_offset_) {
594      backward_branches_++;
595    } else {
596      forward_branches_++;
597    }
598  }
599
600  int GetBranchCount() {
601    return backward_branches_ + forward_branches_;
602  }
603
604  bool IsPseudoMirOp(Instruction::Code opcode) {
605    return static_cast<int>(opcode) >= static_cast<int>(kMirOpFirst);
606  }
607
608  bool IsPseudoMirOp(int opcode) {
609    return opcode >= static_cast<int>(kMirOpFirst);
610  }
611
612  void BasicBlockCombine();
613  void CodeLayout();
614  void DumpCheckStats();
615  void PropagateConstants();
616  MIR* FindMoveResult(BasicBlock* bb, MIR* mir);
617  int SRegToVReg(int ssa_reg) const;
618  void VerifyDataflow();
619  void MethodUseCount();
620  void SSATransformation();
621  void CheckForDominanceFrontier(BasicBlock* dom_bb, const BasicBlock* succ_bb);
622  void NullCheckElimination();
623  /*
624   * Type inference handling helpers.  Because Dalvik's bytecode is not fully typed,
625   * we have to do some work to figure out the sreg type.  For some operations it is
626   * clear based on the opcode (i.e. ADD_FLOAT v0, v1, v2), but for others (MOVE), we
627   * may never know the "real" type.
628   *
629   * We perform the type inference operation by using an iterative  walk over
630   * the graph, propagating types "defined" by typed opcodes to uses and defs in
631   * non-typed opcodes (such as MOVE).  The Setxx(index) helpers are used to set defined
632   * types on typed opcodes (such as ADD_INT).  The Setxx(index, is_xx) form is used to
633   * propagate types through non-typed opcodes such as PHI and MOVE.  The is_xx flag
634   * tells whether our guess of the type is based on a previously typed definition.
635   * If so, the defined type takes precedence.  Note that it's possible to have the same sreg
636   * show multiple defined types because dx treats constants as untyped bit patterns.
637   * The return value of the Setxx() helpers says whether or not the Setxx() action changed
638   * the current guess, and is used to know when to terminate the iterative walk.
639   */
640  bool SetFp(int index, bool is_fp);
641  bool SetFp(int index);
642  bool SetCore(int index, bool is_core);
643  bool SetCore(int index);
644  bool SetRef(int index, bool is_ref);
645  bool SetRef(int index);
646  bool SetWide(int index, bool is_wide);
647  bool SetWide(int index);
648  bool SetHigh(int index, bool is_high);
649  bool SetHigh(int index);
650
651  void AppendMIR(BasicBlock* bb, MIR* mir);
652  void PrependMIR(BasicBlock* bb, MIR* mir);
653  void InsertMIRAfter(BasicBlock* bb, MIR* current_mir, MIR* new_mir);
654  char* GetDalvikDisassembly(const MIR* mir);
655  void ReplaceSpecialChars(std::string& str);
656  std::string GetSSAName(int ssa_reg);
657  std::string GetSSANameWithConst(int ssa_reg, bool singles_only);
658  void GetBlockName(BasicBlock* bb, char* name);
659  const char* GetShortyFromTargetIdx(int);
660  void DumpMIRGraph();
661  CallInfo* NewMemCallInfo(BasicBlock* bb, MIR* mir, InvokeType type, bool is_range);
662  BasicBlock* NewMemBB(BBType block_type, int block_id);
663  MIR* AdvanceMIR(BasicBlock** p_bb, MIR* mir);
664  BasicBlock* NextDominatedBlock(BasicBlock* bb);
665  bool LayoutBlocks(BasicBlock* bb);
666
667  /*
668   * IsDebugBuild sanity check: keep track of the Dex PCs for catch entries so that later on
669   * we can verify that all catch entries have native PC entries.
670   */
671  std::set<uint32_t> catches_;
672
673  // TODO: make these private.
674  RegLocation* reg_location_;                         // Map SSA names to location.
675  GrowableArray<CompilerTemp*> compiler_temps_;
676  SafeMap<unsigned int, unsigned int> block_id_map_;  // Block collapse lookup cache.
677
678  static const int oat_data_flow_attributes_[kMirOpLast];
679  static const char* extended_mir_op_names_[kMirOpLast - kMirOpFirst];
680  static const uint32_t analysis_attributes_[kMirOpLast];
681
682 private:
683  int FindCommonParent(int block1, int block2);
684  void ComputeSuccLineIn(ArenaBitVector* dest, const ArenaBitVector* src1,
685                         const ArenaBitVector* src2);
686  void HandleLiveInUse(ArenaBitVector* use_v, ArenaBitVector* def_v,
687                       ArenaBitVector* live_in_v, int dalvik_reg_id);
688  void HandleDef(ArenaBitVector* def_v, int dalvik_reg_id);
689  void CompilerInitializeSSAConversion();
690  bool DoSSAConversion(BasicBlock* bb);
691  bool InvokeUsesMethodStar(MIR* mir);
692  int ParseInsn(const uint16_t* code_ptr, DecodedInstruction* decoded_instruction);
693  bool ContentIsInsn(const uint16_t* code_ptr);
694  BasicBlock* SplitBlock(DexOffset code_offset, BasicBlock* orig_block,
695                         BasicBlock** immed_pred_block_p);
696  BasicBlock* FindBlock(DexOffset code_offset, bool split, bool create,
697                        BasicBlock** immed_pred_block_p);
698  void ProcessTryCatchBlocks();
699  BasicBlock* ProcessCanBranch(BasicBlock* cur_block, MIR* insn, DexOffset cur_offset, int width,
700                               int flags, const uint16_t* code_ptr, const uint16_t* code_end);
701  void ProcessCanSwitch(BasicBlock* cur_block, MIR* insn, DexOffset cur_offset, int width,
702                        int flags);
703  BasicBlock* ProcessCanThrow(BasicBlock* cur_block, MIR* insn, DexOffset cur_offset, int width,
704                              int flags, ArenaBitVector* try_block_addr, const uint16_t* code_ptr,
705                              const uint16_t* code_end);
706  int AddNewSReg(int v_reg);
707  void HandleSSAUse(int* uses, int dalvik_reg, int reg_index);
708  void HandleSSADef(int* defs, int dalvik_reg, int reg_index);
709  void DataFlowSSAFormat35C(MIR* mir);
710  void DataFlowSSAFormat3RC(MIR* mir);
711  bool FindLocalLiveIn(BasicBlock* bb);
712  void ClearAllVisitedFlags();
713  bool CountUses(struct BasicBlock* bb);
714  bool InferTypeAndSize(BasicBlock* bb);
715  bool VerifyPredInfo(BasicBlock* bb);
716  BasicBlock* NeedsVisit(BasicBlock* bb);
717  BasicBlock* NextUnvisitedSuccessor(BasicBlock* bb);
718  void MarkPreOrder(BasicBlock* bb);
719  void RecordDFSOrders(BasicBlock* bb);
720  void ComputeDFSOrders();
721  void ComputeDefBlockMatrix();
722  void ComputeDomPostOrderTraversal(BasicBlock* bb);
723  void ComputeDominators();
724  void InsertPhiNodes();
725  void DoDFSPreOrderSSARename(BasicBlock* block);
726  void SetConstant(int32_t ssa_reg, int value);
727  void SetConstantWide(int ssa_reg, int64_t value);
728  int GetSSAUseCount(int s_reg);
729  bool BasicBlockOpt(BasicBlock* bb);
730  bool EliminateNullChecks(BasicBlock* bb);
731  void NullCheckEliminationInit(BasicBlock* bb);
732  bool BuildExtendedBBList(struct BasicBlock* bb);
733  bool FillDefBlockMatrix(BasicBlock* bb);
734  void InitializeDominationInfo(BasicBlock* bb);
735  bool ComputeblockIDom(BasicBlock* bb);
736  bool ComputeBlockDominators(BasicBlock* bb);
737  bool SetDominators(BasicBlock* bb);
738  bool ComputeBlockLiveIns(BasicBlock* bb);
739  bool InsertPhiNodeOperands(BasicBlock* bb);
740  bool ComputeDominanceFrontier(BasicBlock* bb);
741  void DoConstantPropogation(BasicBlock* bb);
742  void CountChecks(BasicBlock* bb);
743  bool CombineBlocks(BasicBlock* bb);
744  void AnalyzeBlock(BasicBlock* bb, struct MethodStats* stats);
745  bool ComputeSkipCompilation(struct MethodStats* stats, bool skip_default);
746
747  CompilationUnit* const cu_;
748  GrowableArray<int>* ssa_base_vregs_;
749  GrowableArray<int>* ssa_subscripts_;
750  // Map original Dalvik virtual reg i to the current SSA name.
751  int* vreg_to_ssa_map_;            // length == method->registers_size
752  int* ssa_last_defs_;              // length == method->registers_size
753  ArenaBitVector* is_constant_v_;   // length == num_ssa_reg
754  int* constant_values_;            // length == num_ssa_reg
755  // Use counts of ssa names.
756  GrowableArray<uint32_t> use_counts_;      // Weighted by nesting depth
757  GrowableArray<uint32_t> raw_use_counts_;  // Not weighted
758  unsigned int num_reachable_blocks_;
759  GrowableArray<BasicBlockId>* dfs_order_;
760  GrowableArray<BasicBlockId>* dfs_post_order_;
761  GrowableArray<BasicBlockId>* dom_post_order_traversal_;
762  int* i_dom_list_;
763  ArenaBitVector** def_block_matrix_;    // num_dalvik_register x num_blocks.
764  ArenaBitVector* temp_block_v_;
765  ArenaBitVector* temp_dalvik_register_v_;
766  ArenaBitVector* temp_ssa_register_v_;  // num_ssa_regs.
767  static const int kInvalidEntry = -1;
768  GrowableArray<BasicBlock*> block_list_;
769  ArenaBitVector* try_block_addr_;
770  BasicBlock* entry_block_;
771  BasicBlock* exit_block_;
772  int num_blocks_;
773  const DexFile::CodeItem* current_code_item_;
774  GrowableArray<uint16_t> dex_pc_to_block_map_;  // FindBlock lookup cache.
775  std::vector<DexCompilationUnit*> m_units_;     // List of methods included in this graph
776  typedef std::pair<int, int> MIRLocation;       // Insert point, (m_unit_ index, offset)
777  std::vector<MIRLocation> method_stack_;        // Include stack
778  int current_method_;
779  DexOffset current_offset_;                     // Offset in code units
780  int def_count_;                                // Used to estimate size of ssa name storage.
781  int* opcode_count_;                            // Dex opcode coverage stats.
782  int num_ssa_regs_;                             // Number of names following SSA transformation.
783  std::vector<BasicBlockId> extended_basic_blocks_;  // Heads of block "traces".
784  int method_sreg_;
785  unsigned int attributes_;
786  Checkstats* checkstats_;
787  SpecialCaseHandler special_case_;
788  ArenaAllocator* arena_;
789  int backward_branches_;
790  int forward_branches_;
791};
792
793}  // namespace art
794
795#endif  // ART_COMPILER_DEX_MIR_GRAPH_H_
796