xref: /dports/lang/spidermonkey60/firefox-60.9.0/js/src/jit/IonControlFlow.h

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * vim: set ts=8 sts=4 et sw=4 tw=99:
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef jit_IonControlFlow_h
#define jit_IonControlFlow_h

#include "mozilla/Array.h"

#include "jit/BytecodeAnalysis.h"
#include "jit/FixedList.h"
#include "jit/JitAllocPolicy.h"
#include "js/TypeDecls.h"

namespace js {
namespace jit {

class CFGControlInstruction;

// Adds MFoo::New functions which are mirroring the arguments of the
// constructors. Opcodes which are using this macro can be called with a
// TempAllocator, or the fallible version of the TempAllocator.
#define TRIVIAL_CFG_NEW_WRAPPERS                                             \
  template <typename... Args>                                                \
  static CFGThisOpcode* New(TempAllocator& alloc, Args&&... args) {          \
    return new (alloc) CFGThisOpcode(mozilla::Forward<Args>(args)...);       \
  }                                                                          \
  template <typename... Args>                                                \
  static CFGThisOpcode* New(TempAllocator::Fallible alloc, Args&&... args) { \
    return new (alloc) CFGThisOpcode(mozilla::Forward<Args>(args)...);       \
  }

class CFGSpace {
  static const size_t DEFAULT_CHUNK_SIZE = 4096;

 protected:
  LifoAlloc allocator_;

 public:
  explicit CFGSpace() : allocator_(DEFAULT_CHUNK_SIZE) {}

  LifoAlloc& lifoAlloc() { return allocator_; }

  size_t sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
    return allocator_.sizeOfExcludingThis(mallocSizeOf);
  }
};

class CFGBlock : public TempObject {
  size_t id_;
  jsbytecode* start;
  jsbytecode* stop;
  CFGControlInstruction* end;
  bool inWorkList;

 public:
  explicit CFGBlock(jsbytecode* start)
      : id_(-1), start(start), stop(nullptr), end(nullptr), inWorkList(false) {}

  static CFGBlock* New(TempAllocator& alloc, jsbytecode* start) {
    return new (alloc) CFGBlock(start);
  }

  void operator=(const CFGBlock&) = delete;

  jsbytecode* startPc() const { return start; }
  void setStartPc(jsbytecode* startPc) { start = startPc; }
  jsbytecode* stopPc() const {
    MOZ_ASSERT(stop);
    return stop;
  }
  void setStopPc(jsbytecode* stopPc) { stop = stopPc; }
  CFGControlInstruction* stopIns() const {
    MOZ_ASSERT(end);
    return end;
  }
  void setStopIns(CFGControlInstruction* stopIns) { end = stopIns; }
  bool isInWorkList() const { return inWorkList; }
  void setInWorklist() {
    MOZ_ASSERT(!inWorkList);
    inWorkList = true;
  }
  void clearInWorkList() {
    MOZ_ASSERT(inWorkList);
    inWorkList = false;
  }
  size_t id() const { return id_; }
  void setId(size_t id) { id_ = id; }
};

#define CFG_CONTROL_OPCODE_LIST(_) \
  _(Test)                          \
  _(Compare)                       \
  _(Goto)                          \
  _(Return)                        \
  _(RetRVal)                       \
  _(LoopEntry)                     \
  _(BackEdge)                      \
  _(TableSwitch)                   \
  _(Try)                           \
  _(Throw)

// Forward declarations of MIR types.
#define FORWARD_DECLARE(type) class CFG##type;
CFG_CONTROL_OPCODE_LIST(FORWARD_DECLARE)
#undef FORWARD_DECLARE

#define CFG_CONTROL_HEADER(type_name)                                      \
  static const Type classOpcode = CFGControlInstruction::Type_##type_name; \
  using CFGThisOpcode = CFG##type_name;                                    \
  Type type() const override { return classOpcode; }                       \
  const char* Name() const override { return #type_name; }

class CFGControlInstruction : public TempObject {
 public:
  enum Type {
#define DEFINE_TYPES(type) Type_##type,
    CFG_CONTROL_OPCODE_LIST(DEFINE_TYPES)
#undef DEFINE_TYPES
  };

  virtual size_t numSuccessors() const = 0;
  virtual CFGBlock* getSuccessor(size_t i) const = 0;
  virtual void replaceSuccessor(size_t i, CFGBlock* successor) = 0;
  virtual Type type() const = 0;
  virtual const char* Name() const = 0;

  template <typename CFGType>
  bool is() const {
    return type() == CFGType::classOpcode;
  }
  template <typename CFGType>
  CFGType* to() {
    MOZ_ASSERT(this->is<CFGType>());
    return static_cast<CFGType*>(this);
  }
  template <typename CFGType>
  const CFGType* to() const {
    MOZ_ASSERT(this->is<CFGType>());
    return static_cast<const CFGType*>(this);
  }
#define TYPE_CASTS(type)                                  \
  bool is##type() const { return this->is<CFG##type>(); } \
  CFG##type* to##type() { return this->to<CFG##type>(); } \
  const CFG##type* to##type() const { return this->to<CFG##type>(); }
  CFG_CONTROL_OPCODE_LIST(TYPE_CASTS)
#undef TYPE_CASTS
};

template <size_t Successors>
class CFGAryControlInstruction : public CFGControlInstruction {
  mozilla::Array<CFGBlock*, Successors> successors_;

 public:
  size_t numSuccessors() const final { return Successors; }
  CFGBlock* getSuccessor(size_t i) const final { return successors_[i]; }
  void replaceSuccessor(size_t i, CFGBlock* succ) final {
    successors_[i] = succ;
  }
};

class CFGTry : public CFGControlInstruction {
  CFGBlock* tryBlock_;
  jsbytecode* catchStartPc_;
  CFGBlock* mergePoint_;

  CFGTry(CFGBlock* successor, jsbytecode* catchStartPc, CFGBlock* mergePoint)
      : tryBlock_(successor),
        catchStartPc_(catchStartPc),
        mergePoint_(mergePoint) {}

 public:
  CFG_CONTROL_HEADER(Try)
  TRIVIAL_CFG_NEW_WRAPPERS

  static CFGTry* CopyWithNewTargets(TempAllocator& alloc, CFGTry* old,
                                    CFGBlock* tryBlock, CFGBlock* merge) {
    return new (alloc) CFGTry(tryBlock, old->catchStartPc(), merge);
  }

  size_t numSuccessors() const final { return 2; }
  CFGBlock* getSuccessor(size_t i) const final {
    MOZ_ASSERT(i < numSuccessors());
    return (i == 0) ? tryBlock_ : mergePoint_;
  }
  void replaceSuccessor(size_t i, CFGBlock* succ) final {
    MOZ_ASSERT(i < numSuccessors());
    if (i == 0)
      tryBlock_ = succ;
    else
      mergePoint_ = succ;
  }

  CFGBlock* tryBlock() const { return getSuccessor(0); }

  jsbytecode* catchStartPc() const { return catchStartPc_; }

  CFGBlock* afterTryCatchBlock() const { return getSuccessor(1); }
};

class CFGTableSwitch : public CFGControlInstruction {
  Vector<CFGBlock*, 4, JitAllocPolicy> successors_;
  size_t low_;
  size_t high_;

  CFGTableSwitch(TempAllocator& alloc, size_t low, size_t high)
      : successors_(alloc), low_(low), high_(high) {}

 public:
  CFG_CONTROL_HEADER(TableSwitch);

  static CFGTableSwitch* New(TempAllocator& alloc, size_t low, size_t high) {
    return new (alloc) CFGTableSwitch(alloc, low, high);
  }

  size_t numSuccessors() const final { return successors_.length(); }
  CFGBlock* getSuccessor(size_t i) const final {
    MOZ_ASSERT(i < numSuccessors());
    return successors_[i];
  }
  void replaceSuccessor(size_t i, CFGBlock* succ) final {
    MOZ_ASSERT(i < numSuccessors());
    successors_[i] = succ;
  }

  bool addDefault(CFGBlock* defaultCase) {
    MOZ_ASSERT(successors_.length() == 0);
    return successors_.append(defaultCase);
  }

  bool addCase(CFGBlock* caseBlock) {
    MOZ_ASSERT(successors_.length() > 0);
    return successors_.append(caseBlock);
  }

  CFGBlock* defaultCase() const { return getSuccessor(0); }

  CFGBlock* getCase(size_t i) const { return getSuccessor(i + 1); }

  size_t high() const { return high_; }

  size_t low() const { return low_; }
};

/**
 * CFGCompare
 *
 * PEEK
 * PEEK
 * STRICTEQ
 *    POP truePopAmount
 *    JUMP succ1
 * STRICTNEQ
 *    POP falsePopAmount
 *    JUMP succ2
 */
class CFGCompare : public CFGAryControlInstruction<2> {
  const size_t truePopAmount_;
  const size_t falsePopAmount_;

  CFGCompare(CFGBlock* succ1, size_t truePopAmount, CFGBlock* succ2,
             size_t falsePopAmount)
      : truePopAmount_(truePopAmount), falsePopAmount_(falsePopAmount) {
    replaceSuccessor(0, succ1);
    replaceSuccessor(1, succ2);
  }

 public:
  CFG_CONTROL_HEADER(Compare);

  static CFGCompare* NewFalseBranchIsDefault(TempAllocator& alloc,
                                             CFGBlock* case_,
                                             CFGBlock* default_) {
    // True and false branch both go to a body and don't need the lhs and
    // rhs to the compare. Pop them.
    return new (alloc) CFGCompare(case_, 2, default_, 2);
  }

  static CFGCompare* NewFalseBranchIsNextCompare(TempAllocator& alloc,
                                                 CFGBlock* case_,
                                                 CFGBlock* nextCompare) {
    // True branch goes to the body and don't need the lhs and
    // rhs to the compare anymore. Pop them. The next compare still
    // needs the lhs.
    return new (alloc) CFGCompare(case_, 2, nextCompare, 1);
  }

  static CFGCompare* CopyWithNewTargets(TempAllocator& alloc, CFGCompare* old,
                                        CFGBlock* succ1, CFGBlock* succ2) {
    return new (alloc)
        CFGCompare(succ1, old->truePopAmount(), succ2, old->falsePopAmount());
  }

  CFGBlock* trueBranch() const { return getSuccessor(0); }
  CFGBlock* falseBranch() const { return getSuccessor(1); }
  size_t truePopAmount() const { return truePopAmount_; }
  size_t falsePopAmount() const { return falsePopAmount_; }
};

/**
 * CFGTest
 *
 * POP / PEEK (depending on keepCondition_)
 * IFEQ JUMP succ1
 * IFNEQ JUMP succ2
 *
 */
class CFGTest : public CFGAryControlInstruction<2> {
  // By default the condition gets popped. This variable
  // keeps track if we want to keep the condition.
  bool keepCondition_;

  CFGTest(CFGBlock* succ1, CFGBlock* succ2) : keepCondition_(false) {
    replaceSuccessor(0, succ1);
    replaceSuccessor(1, succ2);
  }
  CFGTest(CFGBlock* succ1, CFGBlock* succ2, bool keepCondition)
      : keepCondition_(keepCondition) {
    replaceSuccessor(0, succ1);
    replaceSuccessor(1, succ2);
  }

 public:
  CFG_CONTROL_HEADER(Test);
  TRIVIAL_CFG_NEW_WRAPPERS

  static CFGTest* CopyWithNewTargets(TempAllocator& alloc, CFGTest* old,
                                     CFGBlock* succ1, CFGBlock* succ2) {
    return new (alloc) CFGTest(succ1, succ2, old->mustKeepCondition());
  }

  CFGBlock* trueBranch() const { return getSuccessor(0); }
  CFGBlock* falseBranch() const { return getSuccessor(1); }
  void keepCondition() { keepCondition_ = true; }
  bool mustKeepCondition() const { return keepCondition_; }
};

/**
 * CFGReturn
 *
 * POP
 * RETURN popped value
 *
 */
class CFGReturn : public CFGAryControlInstruction<0> {
 public:
  CFG_CONTROL_HEADER(Return);
  TRIVIAL_CFG_NEW_WRAPPERS
};

/**
 * CFGRetRVal
 *
 * RETURN the value in the return value slot
 *
 */
class CFGRetRVal : public CFGAryControlInstruction<0> {
 public:
  CFG_CONTROL_HEADER(RetRVal);
  TRIVIAL_CFG_NEW_WRAPPERS
};

/**
 * CFGThrow
 *
 * POP
 * THROW popped value
 *
 */
class CFGThrow : public CFGAryControlInstruction<0> {
 public:
  CFG_CONTROL_HEADER(Throw);
  TRIVIAL_CFG_NEW_WRAPPERS
};

class CFGUnaryControlInstruction : public CFGAryControlInstruction<1> {
 public:
  explicit CFGUnaryControlInstruction(CFGBlock* block) {
    MOZ_ASSERT(block);
    replaceSuccessor(0, block);
  }

  CFGBlock* successor() const { return getSuccessor(0); }
};

/**
 * CFGGOTO
 *
 * POP (x popAmount)
 * JMP block
 *
 */
class CFGGoto : public CFGUnaryControlInstruction {
  const size_t popAmount_;

  explicit CFGGoto(CFGBlock* block)
      : CFGUnaryControlInstruction(block), popAmount_(0) {}

  CFGGoto(CFGBlock* block, size_t popAmount_)
      : CFGUnaryControlInstruction(block), popAmount_(popAmount_) {}

 public:
  CFG_CONTROL_HEADER(Goto);
  TRIVIAL_CFG_NEW_WRAPPERS

  static CFGGoto* CopyWithNewTargets(TempAllocator& alloc, CFGGoto* old,
                                     CFGBlock* block) {
    return new (alloc) CFGGoto(block, old->popAmount());
  }

  size_t popAmount() const { return popAmount_; }
};

/**
 * CFGBackEdge
 *
 * Jumps back to the start of the loop.
 *
 * JMP block
 *
 */
class CFGBackEdge : public CFGUnaryControlInstruction {
  explicit CFGBackEdge(CFGBlock* block) : CFGUnaryControlInstruction(block) {}

 public:
  CFG_CONTROL_HEADER(BackEdge);
  TRIVIAL_CFG_NEW_WRAPPERS

  static CFGBackEdge* CopyWithNewTargets(TempAllocator& alloc, CFGBackEdge* old,
                                         CFGBlock* block) {
    return new (alloc) CFGBackEdge(block);
  }
};

/**
 * CFGLOOPENTRY
 *
 * Indicates the jumping block is the start of a loop.
 * That block is the only block allowed to have a backedge.
 *
 * JMP block
 *
 */
class CFGLoopEntry : public CFGUnaryControlInstruction {
  bool canOsr_;
  bool isForIn_;
  size_t stackPhiCount_;
  jsbytecode* loopStopPc_;

  CFGLoopEntry(CFGBlock* block, size_t stackPhiCount)
      : CFGUnaryControlInstruction(block),
        canOsr_(false),
        isForIn_(false),
        stackPhiCount_(stackPhiCount),
        loopStopPc_(nullptr) {}

  CFGLoopEntry(CFGBlock* block, bool canOsr, bool isForIn, size_t stackPhiCount,
               jsbytecode* loopStopPc)
      : CFGUnaryControlInstruction(block),
        canOsr_(canOsr),
        isForIn_(isForIn),
        stackPhiCount_(stackPhiCount),
        loopStopPc_(loopStopPc) {}

 public:
  CFG_CONTROL_HEADER(LoopEntry);
  TRIVIAL_CFG_NEW_WRAPPERS

  static CFGLoopEntry* CopyWithNewTargets(TempAllocator& alloc,
                                          CFGLoopEntry* old,
                                          CFGBlock* loopEntry) {
    return new (alloc) CFGLoopEntry(loopEntry, old->canOsr(), old->isForIn(),
                                    old->stackPhiCount(), old->loopStopPc());
  }

  void setCanOsr() { canOsr_ = true; }

  bool canOsr() const { return canOsr_; }

  void setIsForIn() { isForIn_ = true; }
  bool isForIn() const { return isForIn_; }

  size_t stackPhiCount() const { return stackPhiCount_; }

  jsbytecode* loopStopPc() const {
    MOZ_ASSERT(loopStopPc_);
    return loopStopPc_;
  }

  void setLoopStopPc(jsbytecode* loopStopPc) { loopStopPc_ = loopStopPc; }
};

typedef Vector<CFGBlock*, 4, JitAllocPolicy> CFGBlockVector;

class ControlFlowGraph : public TempObject {
  // A list of blocks in RPO, containing per block a pc-range and
  // a control instruction.
  Vector<CFGBlock, 4, JitAllocPolicy> blocks_;

  explicit ControlFlowGraph(TempAllocator& alloc) : blocks_(alloc) {}

 public:
  static ControlFlowGraph* New(TempAllocator& alloc) {
    return new (alloc) ControlFlowGraph(alloc);
  }

  ControlFlowGraph(const ControlFlowGraph&) = delete;
  void operator=(const ControlFlowGraph&) = delete;

  void dump(GenericPrinter& print, JSScript* script);
  bool init(TempAllocator& alloc, const CFGBlockVector& blocks);

  const CFGBlock* block(size_t i) const { return &blocks_[i]; }

  size_t numBlocks() const { return blocks_.length(); }
};

class ControlFlowGenerator {
  static int CmpSuccessors(const void* a, const void* b);

  JSScript* script;
  CFGBlock* current;
  jsbytecode* pc;
  GSNCache gsn;
  TempAllocator& alloc_;
  CFGBlockVector blocks_;

 public:
  ControlFlowGenerator(const ControlFlowGenerator&) = delete;
  void operator=(const ControlFlowGenerator&) = delete;

  TempAllocator& alloc() { return alloc_; }

  enum class ControlStatus {
    Error,
    Abort,
    Ended,   // There is no continuation/join point.
    Joined,  // Created a join node.
    Jumped,  // Parsing another branch at the same level.
    None     // No control flow.
  };

  struct DeferredEdge : public TempObject {
    CFGBlock* block;
    DeferredEdge* next;

    DeferredEdge(CFGBlock* block, DeferredEdge* next)
        : block(block), next(next) {}
  };

  struct ControlFlowInfo {
    // Entry in the cfgStack.
    uint32_t cfgEntry;

    // Label that continues go to.
    jsbytecode* continuepc;

    ControlFlowInfo(uint32_t cfgEntry, jsbytecode* continuepc)
        : cfgEntry(cfgEntry), continuepc(continuepc) {}
  };

  // To avoid recursion, the bytecode analyzer uses a stack where each entry
  // is a small state machine. As we encounter branches or jumps in the
  // bytecode, we push information about the edges on the stack so that the
  // CFG can be built in a tree-like fashion.
  struct CFGState {
    enum State {
      IF_TRUE,             // if() { }, no else.
      IF_TRUE_EMPTY_ELSE,  // if() { }, empty else
      IF_ELSE_TRUE,        // if() { X } else { }
      IF_ELSE_FALSE,       // if() { } else { X }
      DO_WHILE_LOOP_BODY,  // do { x } while ()
      DO_WHILE_LOOP_COND,  // do { } while (x)
      WHILE_LOOP_COND,     // while (x) { }
      WHILE_LOOP_BODY,     // while () { x }
      FOR_LOOP_COND,       // for (; x;) { }
      FOR_LOOP_BODY,       // for (; ;) { x }
      FOR_LOOP_UPDATE,     // for (; ; x) { }
      TABLE_SWITCH,        // switch() { x }
      COND_SWITCH_CASE,    // switch() { case X: ... }
      COND_SWITCH_BODY,    // switch() { case ...: X }
      AND_OR,              // && x, || x
      LABEL,               // label: x
      TRY                  // try { x } catch(e) { }
    };

    State state;         // Current state of this control structure.
    jsbytecode* stopAt;  // Bytecode at which to stop the processing loop.

    // For if structures, this contains branch information.
    union {
      struct {
        CFGBlock* ifFalse;
        jsbytecode* falseEnd;
        CFGBlock* ifTrue;  // Set when the end of the true path is reached.
        CFGTest* test;
      } branch;
      struct {
        // Common entry point.
        CFGBlock* entry;

        // Position of where the loop body starts and ends.
        jsbytecode* bodyStart;
        jsbytecode* bodyEnd;

        // pc immediately after the loop exits.
        jsbytecode* exitpc;

        // Common exit point. Created lazily, so it may be nullptr.
        CFGBlock* successor;

        // Deferred break and continue targets.
        DeferredEdge* breaks;
        DeferredEdge* continues;

        // Initial state, in case loop processing is restarted.
        State initialState;
        jsbytecode* initialPc;
        jsbytecode* initialStopAt;
        jsbytecode* loopHead;

        // For-loops only.
        jsbytecode* condpc;
        jsbytecode* updatepc;
        jsbytecode* updateEnd;
      } loop;
      struct {
        // Vector of body blocks to process after the cases.
        FixedList<CFGBlock*>* bodies;

        // When processing case statements, this counter points at the
        // last uninitialized body.  When processing bodies, this
        // counter targets the next body to process.
        uint32_t currentIdx;

        // Remember the block index of the default case.
        jsbytecode* defaultTarget;
        uint32_t defaultIdx;

        // Block immediately after the switch.
        jsbytecode* exitpc;
        DeferredEdge* breaks;
      } switch_;
      struct {
        DeferredEdge* breaks;
      } label;
      struct {
        CFGBlock* successor;
      } try_;
    };

    inline bool isLoop() const {
      switch (state) {
        case DO_WHILE_LOOP_COND:
        case DO_WHILE_LOOP_BODY:
        case WHILE_LOOP_COND:
        case WHILE_LOOP_BODY:
        case FOR_LOOP_COND:
        case FOR_LOOP_BODY:
        case FOR_LOOP_UPDATE:
          return true;
        default:
          return false;
      }
    }

    static CFGState If(jsbytecode* join, CFGTest* test);
    static CFGState IfElse(jsbytecode* trueEnd, jsbytecode* falseEnd,
                           CFGTest* test);
    static CFGState AndOr(jsbytecode* join, CFGBlock* lhs);
    static CFGState TableSwitch(TempAllocator& alloc, jsbytecode* exitpc);
    static CFGState CondSwitch(TempAllocator& alloc, jsbytecode* exitpc,
                               jsbytecode* defaultTarget);
    static CFGState Label(jsbytecode* exitpc);
    static CFGState Try(jsbytecode* exitpc, CFGBlock* successor);
  };

  Vector<CFGState, 8, JitAllocPolicy> cfgStack_;
  Vector<ControlFlowInfo, 4, JitAllocPolicy> loops_;
  Vector<ControlFlowInfo, 0, JitAllocPolicy> switches_;
  Vector<ControlFlowInfo, 2, JitAllocPolicy> labels_;
  bool aborted_;
  bool checkedTryFinally_;

 public:
  ControlFlowGenerator(TempAllocator& alloc, JSScript* script);

  MOZ_MUST_USE bool traverseBytecode();
  MOZ_MUST_USE bool addBlock(CFGBlock* block);
  ControlFlowGraph* getGraph(TempAllocator& alloc) {
    ControlFlowGraph* cfg = ControlFlowGraph::New(alloc);
    if (!cfg) return nullptr;
    if (!cfg->init(alloc, blocks_)) return nullptr;
    return cfg;
  }

  bool aborted() const { return aborted_; }

 private:
  void popCfgStack();
  MOZ_MUST_USE bool processDeferredContinues(CFGState& state);
  ControlStatus processControlEnd();
  ControlStatus processCfgStack();
  ControlStatus processCfgEntry(CFGState& state);
  ControlStatus processIfStart(JSOp op);
  ControlStatus processIfEnd(CFGState& state);
  ControlStatus processIfElseTrueEnd(CFGState& state);
  ControlStatus processIfElseFalseEnd(CFGState& state);
  ControlStatus processDoWhileLoop(jssrcnote* sn);
  ControlStatus processDoWhileBodyEnd(CFGState& state);
  ControlStatus processDoWhileCondEnd(CFGState& state);
  ControlStatus processWhileCondEnd(CFGState& state);
  ControlStatus processWhileBodyEnd(CFGState& state);
  ControlStatus processForLoop(JSOp op, jssrcnote* sn);
  ControlStatus processForCondEnd(CFGState& state);
  ControlStatus processForBodyEnd(CFGState& state);
  ControlStatus processForUpdateEnd(CFGState& state);
  ControlStatus processWhileOrForInLoop(jssrcnote* sn);
  ControlStatus processNextTableSwitchCase(CFGState& state);
  ControlStatus processCondSwitch();
  ControlStatus processCondSwitchCase(CFGState& state);
  ControlStatus processCondSwitchDefault(CFGState& state);
  ControlStatus processCondSwitchBody(CFGState& state);
  ControlStatus processSwitchBreak(JSOp op);
  ControlStatus processSwitchEnd(DeferredEdge* breaks, jsbytecode* exitpc);
  ControlStatus processTry();
  ControlStatus processTryEnd(CFGState& state);
  ControlStatus processThrow();
  ControlStatus processTableSwitch(JSOp op, jssrcnote* sn);
  ControlStatus processContinue(JSOp op);
  ControlStatus processBreak(JSOp op, jssrcnote* sn);
  ControlStatus processReturn(JSOp op);
  ControlStatus maybeLoop(JSOp op, jssrcnote* sn);
  ControlStatus snoopControlFlow(JSOp op);
  ControlStatus processBrokenLoop(CFGState& state);
  ControlStatus finishLoop(CFGState& state, CFGBlock* successor);
  ControlStatus processAndOr(JSOp op);
  ControlStatus processAndOrEnd(CFGState& state);
  ControlStatus processLabel();
  ControlStatus processLabelEnd(CFGState& state);

  MOZ_MUST_USE bool pushLoop(CFGState::State state, jsbytecode* stopAt,
                             CFGBlock* entry, jsbytecode* loopHead,
                             jsbytecode* initialPc, jsbytecode* bodyStart,
                             jsbytecode* bodyEnd, jsbytecode* exitpc,
                             jsbytecode* continuepc);
  void endCurrentBlock(CFGControlInstruction* ins);
  CFGBlock* createBreakCatchBlock(DeferredEdge* edge, jsbytecode* pc);
};

}  // namespace jit
}  // namespace js

#endif /* jit_IonControlFlow_h */