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/* -*- 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 js_Utility_h
#define js_Utility_h

#include "mozilla/Assertions.h"
#include "mozilla/Atomics.h"
#include "mozilla/Attributes.h"
#include "mozilla/Compiler.h"
#include "mozilla/Move.h"
#include "mozilla/Scoped.h"
#include "mozilla/TemplateLib.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/WrappingOperations.h"

#include <stdlib.h>
#include <string.h>

#ifdef JS_OOM_DO_BACKTRACES
#include <execinfo.h>
#include <stdio.h>
#endif

#include "jstypes.h"

#include "mozmemory.h"

/* The public JS engine namespace. */
namespace JS {}

/* The mozilla-shared reusable template/utility namespace. */
namespace mozilla {}

/* The private JS engine namespace. */
namespace js {}

#define JS_STATIC_ASSERT(cond) static_assert(cond, "JS_STATIC_ASSERT")
#define JS_STATIC_ASSERT_IF(cond, expr) \
  MOZ_STATIC_ASSERT_IF(cond, expr, "JS_STATIC_ASSERT_IF")

extern MOZ_NORETURN MOZ_COLD JS_PUBLIC_API void JS_Assert(const char* s,
                                                          const char* file,
                                                          int ln);

/*
 * Custom allocator support for SpiderMonkey
 */
#if defined JS_USE_CUSTOM_ALLOCATOR
#include "jscustomallocator.h"
#else

namespace js {

/*
 * Thread types are used to tag threads for certain kinds of testing (see
 * below), and also used to characterize threads in the thread scheduler (see
 * js/src/vm/HelperThreads.cpp).
 *
 * Please update oom::FirstThreadTypeToTest and oom::LastThreadTypeToTest when
 * adding new thread types.
 */
enum ThreadType {
  THREAD_TYPE_NONE = 0,      // 0
  THREAD_TYPE_COOPERATING,   // 1
  THREAD_TYPE_WASM,          // 2
  THREAD_TYPE_ION,           // 3
  THREAD_TYPE_PARSE,         // 4
  THREAD_TYPE_COMPRESS,      // 5
  THREAD_TYPE_GCHELPER,      // 6
  THREAD_TYPE_GCPARALLEL,    // 7
  THREAD_TYPE_PROMISE_TASK,  // 8
  THREAD_TYPE_ION_FREE,      // 9
  THREAD_TYPE_WASM_TIER2,    // 10
  THREAD_TYPE_WORKER,        // 11
  THREAD_TYPE_MAX            // Used to check shell function arguments
};

namespace oom {

/*
 * Theads are tagged only in certain debug contexts.  Notably, to make testing
 * OOM in certain helper threads more effective, we allow restricting the OOM
 * testing to a certain helper thread type. This allows us to fail e.g. in
 * off-thread script parsing without causing an OOM in the active thread first.
 *
 * Getter/Setter functions to encapsulate mozilla::ThreadLocal, implementation
 * is in jsutil.cpp.
 */
#if defined(DEBUG) || defined(JS_OOM_BREAKPOINT)

// Define the range of threads tested by simulated OOM testing and the
// like. Testing worker threads is not supported.
const ThreadType FirstThreadTypeToTest = THREAD_TYPE_COOPERATING;
const ThreadType LastThreadTypeToTest = THREAD_TYPE_WASM_TIER2;

extern bool InitThreadType(void);
extern void SetThreadType(ThreadType);
extern JS_FRIEND_API uint32_t GetThreadType(void);

#else

inline bool InitThreadType(void) { return true; }
inline void SetThreadType(ThreadType t){};
inline uint32_t GetThreadType(void) { return 0; }

#endif

} /* namespace oom */
} /* namespace js */

#if defined(DEBUG) || defined(JS_OOM_BREAKPOINT)

#ifdef JS_OOM_BREAKPOINT
#if defined(_MSC_VER)
static MOZ_NEVER_INLINE void js_failedAllocBreakpoint() {
  __asm {}
  ;
}
#else
static MOZ_NEVER_INLINE void js_failedAllocBreakpoint() { asm(""); }
#endif
#define JS_OOM_CALL_BP_FUNC() js_failedAllocBreakpoint()
#else
#define JS_OOM_CALL_BP_FUNC() \
  do {                        \
  } while (0)
#endif

namespace js {
namespace oom {

/*
 * Out of memory testing support.  We provide various testing functions to
 * simulate OOM conditions and so we can test that they are handled correctly.
 */

extern JS_PUBLIC_DATA uint32_t targetThread;
extern JS_PUBLIC_DATA uint64_t maxAllocations;
extern JS_PUBLIC_DATA uint64_t counter;
extern JS_PUBLIC_DATA bool failAlways;

extern void SimulateOOMAfter(uint64_t allocations, uint32_t thread,
                             bool always);

extern void ResetSimulatedOOM();

inline bool IsThreadSimulatingOOM() {
  return js::oom::targetThread &&
         js::oom::targetThread == js::oom::GetThreadType();
}

inline bool IsSimulatedOOMAllocation() {
  return IsThreadSimulatingOOM() && (counter == maxAllocations ||
                                     (counter > maxAllocations && failAlways));
}

inline bool ShouldFailWithOOM() {
  if (!IsThreadSimulatingOOM()) return false;

  counter++;
  if (IsSimulatedOOMAllocation()) {
    JS_OOM_CALL_BP_FUNC();
    return true;
  }
  return false;
}

inline bool HadSimulatedOOM() { return counter >= maxAllocations; }

/*
 * Out of stack space testing support, similar to OOM testing functions.
 */

extern JS_PUBLIC_DATA uint32_t stackTargetThread;
extern JS_PUBLIC_DATA uint64_t maxStackChecks;
extern JS_PUBLIC_DATA uint64_t stackCheckCounter;
extern JS_PUBLIC_DATA bool stackCheckFailAlways;

extern void SimulateStackOOMAfter(uint64_t checks, uint32_t thread,
                                  bool always);

extern void ResetSimulatedStackOOM();

inline bool IsThreadSimulatingStackOOM() {
  return js::oom::stackTargetThread &&
         js::oom::stackTargetThread == js::oom::GetThreadType();
}

inline bool IsSimulatedStackOOMCheck() {
  return IsThreadSimulatingStackOOM() &&
         (stackCheckCounter == maxStackChecks ||
          (stackCheckCounter > maxStackChecks && stackCheckFailAlways));
}

inline bool ShouldFailWithStackOOM() {
  if (!IsThreadSimulatingStackOOM()) return false;

  stackCheckCounter++;
  if (IsSimulatedStackOOMCheck()) {
    JS_OOM_CALL_BP_FUNC();
    return true;
  }
  return false;
}

inline bool HadSimulatedStackOOM() {
  return stackCheckCounter >= maxStackChecks;
}

/*
 * Interrupt testing support, similar to OOM testing functions.
 */

extern JS_PUBLIC_DATA uint32_t interruptTargetThread;
extern JS_PUBLIC_DATA uint64_t maxInterruptChecks;
extern JS_PUBLIC_DATA uint64_t interruptCheckCounter;
extern JS_PUBLIC_DATA bool interruptCheckFailAlways;

extern void SimulateInterruptAfter(uint64_t checks, uint32_t thread,
                                   bool always);

extern void ResetSimulatedInterrupt();

inline bool IsThreadSimulatingInterrupt() {
  return js::oom::interruptTargetThread &&
         js::oom::interruptTargetThread == js::oom::GetThreadType();
}

inline bool IsSimulatedInterruptCheck() {
  return IsThreadSimulatingInterrupt() &&
         (interruptCheckCounter == maxInterruptChecks ||
          (interruptCheckCounter > maxInterruptChecks &&
           interruptCheckFailAlways));
}

inline bool ShouldFailWithInterrupt() {
  if (!IsThreadSimulatingInterrupt()) return false;

  interruptCheckCounter++;
  if (IsSimulatedInterruptCheck()) {
    JS_OOM_CALL_BP_FUNC();
    return true;
  }
  return false;
}

inline bool HadSimulatedInterrupt() {
  return interruptCheckCounter >= maxInterruptChecks;
}

} /* namespace oom */
} /* namespace js */

#define JS_OOM_POSSIBLY_FAIL()                        \
  do {                                                \
    if (js::oom::ShouldFailWithOOM()) return nullptr; \
  } while (0)

#define JS_OOM_POSSIBLY_FAIL_BOOL()                 \
  do {                                              \
    if (js::oom::ShouldFailWithOOM()) return false; \
  } while (0)

#define JS_STACK_OOM_POSSIBLY_FAIL()                     \
  do {                                                   \
    if (js::oom::ShouldFailWithStackOOM()) return false; \
  } while (0)

#define JS_STACK_OOM_POSSIBLY_FAIL_REPORT()  \
  do {                                       \
    if (js::oom::ShouldFailWithStackOOM()) { \
      ReportOverRecursed(cx);                \
      return false;                          \
    }                                        \
  } while (0)

#define JS_INTERRUPT_POSSIBLY_FAIL()                        \
  do {                                                      \
    if (MOZ_UNLIKELY(js::oom::ShouldFailWithInterrupt())) { \
      cx->interrupt_ = true;                                \
      return cx->handleInterrupt();                         \
    }                                                       \
  } while (0)

#else

#define JS_OOM_POSSIBLY_FAIL() \
  do {                         \
  } while (0)
#define JS_OOM_POSSIBLY_FAIL_BOOL() \
  do {                              \
  } while (0)
#define JS_STACK_OOM_POSSIBLY_FAIL() \
  do {                               \
  } while (0)
#define JS_STACK_OOM_POSSIBLY_FAIL_REPORT() \
  do {                                      \
  } while (0)
#define JS_INTERRUPT_POSSIBLY_FAIL() \
  do {                               \
  } while (0)
namespace js {
namespace oom {
static inline bool IsSimulatedOOMAllocation() { return false; }
static inline bool ShouldFailWithOOM() { return false; }
} /* namespace oom */
} /* namespace js */

#endif /* DEBUG || JS_OOM_BREAKPOINT */

namespace js {

/* Disable OOM testing in sections which are not OOM safe. */
struct MOZ_RAII JS_PUBLIC_DATA AutoEnterOOMUnsafeRegion {
  MOZ_NORETURN MOZ_COLD void crash(const char* reason);
  MOZ_NORETURN MOZ_COLD void crash(size_t size, const char* reason);

  using AnnotateOOMAllocationSizeCallback = void (*)(size_t);
  static AnnotateOOMAllocationSizeCallback annotateOOMSizeCallback;
  static void setAnnotateOOMAllocationSizeCallback(
      AnnotateOOMAllocationSizeCallback callback) {
    annotateOOMSizeCallback = callback;
  }

#if defined(DEBUG) || defined(JS_OOM_BREAKPOINT)
  AutoEnterOOMUnsafeRegion()
      : oomEnabled_(oom::IsThreadSimulatingOOM() &&
                    oom::maxAllocations != UINT64_MAX),
        oomAfter_(0) {
    if (oomEnabled_) {
      MOZ_ALWAYS_TRUE(owner_.compareExchange(nullptr, this));
      oomAfter_ = int64_t(oom::maxAllocations) - int64_t(oom::counter);
      oom::maxAllocations = UINT64_MAX;
    }
  }

  ~AutoEnterOOMUnsafeRegion() {
    if (oomEnabled_) {
      MOZ_ASSERT(oom::maxAllocations == UINT64_MAX);
      int64_t maxAllocations = int64_t(oom::counter) + oomAfter_;
      MOZ_ASSERT(maxAllocations >= 0,
                 "alloc count + oom limit exceeds range, your oom limit is "
                 "probably too large");
      oom::maxAllocations = uint64_t(maxAllocations);
      MOZ_ALWAYS_TRUE(owner_.compareExchange(this, nullptr));
    }
  }

 private:
  // Used to catch concurrent use from other threads.
  static mozilla::Atomic<AutoEnterOOMUnsafeRegion*> owner_;

  bool oomEnabled_;
  int64_t oomAfter_;
#endif
};

} /* namespace js */

// Malloc allocation.

namespace js {

extern JS_PUBLIC_DATA arena_id_t MallocArena;

extern void InitMallocAllocator();
extern void ShutDownMallocAllocator();

} /* namespace js */

static inline void* js_malloc(size_t bytes) {
  JS_OOM_POSSIBLY_FAIL();
  return moz_arena_malloc(js::MallocArena, bytes);
}

static inline void* js_calloc(size_t bytes) {
  JS_OOM_POSSIBLY_FAIL();
  return moz_arena_calloc(js::MallocArena, bytes, 1);
}

static inline void* js_calloc(size_t nmemb, size_t size) {
  JS_OOM_POSSIBLY_FAIL();
  return moz_arena_calloc(js::MallocArena, nmemb, size);
}

static inline void* js_realloc(void* p, size_t bytes) {
  // realloc() with zero size is not portable, as some implementations may
  // return nullptr on success and free |p| for this.  We assume nullptr
  // indicates failure and that |p| is still valid.
  MOZ_ASSERT(bytes != 0);

  JS_OOM_POSSIBLY_FAIL();
  return moz_arena_realloc(js::MallocArena, p, bytes);
}

static inline void js_free(void* p) {
  // TODO: This should call |moz_arena_free(js::MallocArena, p)| but we
  // currently can't enforce that all memory freed here was allocated by
  // js_malloc().
  free(p);
}

JS_PUBLIC_API char* js_strdup(const char* s);
#endif /* JS_USE_CUSTOM_ALLOCATOR */

#include <new>

/*
 * Low-level memory management in SpiderMonkey:
 *
 *  ** Do not use the standard malloc/free/realloc: SpiderMonkey allows these
 *     to be redefined (via JS_USE_CUSTOM_ALLOCATOR) and Gecko even #define's
 *     these symbols.
 *
 *  ** Do not use the builtin C++ operator new and delete: these throw on
 *     error and we cannot override them not to.
 *
 * Allocation:
 *
 * - If the lifetime of the allocation is tied to the lifetime of a GC-thing
 *   (that is, finalizing the GC-thing will free the allocation), call one of
 *   the following functions:
 *
 *     JSContext::{malloc_,realloc_,calloc_,new_}
 *     JSRuntime::{malloc_,realloc_,calloc_,new_}
 *
 *   These functions accumulate the number of bytes allocated which is used as
 *   part of the GC-triggering heuristic.
 *
 *   The difference between the JSContext and JSRuntime versions is that the
 *   cx version reports an out-of-memory error on OOM. (This follows from the
 *   general SpiderMonkey idiom that a JSContext-taking function reports its
 *   own errors.)
 *
 * - Otherwise, use js_malloc/js_realloc/js_calloc/js_new
 *
 * Deallocation:
 *
 * - Ordinarily, use js_free/js_delete.
 *
 * - For deallocations during GC finalization, use one of the following
 *   operations on the FreeOp provided to the finalizer:
 *
 *     FreeOp::{free_,delete_}
 *
 *   The advantage of these operations is that the memory is batched and freed
 *   on another thread.
 */

/*
 * Given a class which should provide a 'new' method, add
 * JS_DECLARE_NEW_METHODS (see js::MallocProvider for an example).
 *
 * Note: Do not add a ; at the end of a use of JS_DECLARE_NEW_METHODS,
 * or the build will break.
 */
#define JS_DECLARE_NEW_METHODS(NEWNAME, ALLOCATOR, QUALIFIERS)         \
  template <class T, typename... Args>                                 \
  QUALIFIERS T* NEWNAME(Args&&... args) MOZ_HEAP_ALLOCATOR {           \
    void* memory = ALLOCATOR(sizeof(T));                               \
    return MOZ_LIKELY(memory) ? new (memory)                           \
                                    T(mozilla::Forward<Args>(args)...) \
                              : nullptr;                               \
  }

/*
 * Given a class which should provide 'make' methods, add
 * JS_DECLARE_MAKE_METHODS (see js::MallocProvider for an example).  This
 * method is functionally the same as JS_DECLARE_NEW_METHODS: it just declares
 * methods that return mozilla::UniquePtr instances that will singly-manage
 * ownership of the created object.
 *
 * Note: Do not add a ; at the end of a use of JS_DECLARE_MAKE_METHODS,
 * or the build will break.
 */
#define JS_DECLARE_MAKE_METHODS(MAKENAME, NEWNAME, QUALIFIERS)    \
  template <class T, typename... Args>                            \
  QUALIFIERS mozilla::UniquePtr<T, JS::DeletePolicy<T>> MAKENAME( \
      Args&&... args) MOZ_HEAP_ALLOCATOR {                        \
    T* ptr = NEWNAME<T>(mozilla::Forward<Args>(args)...);         \
    return mozilla::UniquePtr<T, JS::DeletePolicy<T>>(ptr);       \
  }

JS_DECLARE_NEW_METHODS(js_new, js_malloc, static MOZ_ALWAYS_INLINE)

namespace js {

/*
 * Calculate the number of bytes needed to allocate |numElems| contiguous
 * instances of type |T|.  Return false if the calculation overflowed.
 */
template <typename T>
MOZ_MUST_USE inline bool CalculateAllocSize(size_t numElems, size_t* bytesOut) {
  *bytesOut = numElems * sizeof(T);
  return (numElems & mozilla::tl::MulOverflowMask<sizeof(T)>::value) == 0;
}

/*
 * Calculate the number of bytes needed to allocate a single instance of type
 * |T| followed by |numExtra| contiguous instances of type |Extra|.  Return
 * false if the calculation overflowed.
 */
template <typename T, typename Extra>
MOZ_MUST_USE inline bool CalculateAllocSizeWithExtra(size_t numExtra,
                                                     size_t* bytesOut) {
  *bytesOut = sizeof(T) + numExtra * sizeof(Extra);
  return (numExtra & mozilla::tl::MulOverflowMask<sizeof(Extra)>::value) == 0 &&
         *bytesOut >= sizeof(T);
}

} /* namespace js */

template <class T>
static MOZ_ALWAYS_INLINE void js_delete(const T* p) {
  if (p) {
    p->~T();
    js_free(const_cast<T*>(p));
  }
}

template <class T>
static MOZ_ALWAYS_INLINE void js_delete_poison(const T* p) {
  if (p) {
    p->~T();
    memset(const_cast<T*>(p), 0x3B, sizeof(T));
    js_free(const_cast<T*>(p));
  }
}

template <class T>
static MOZ_ALWAYS_INLINE T* js_pod_malloc() {
  return static_cast<T*>(js_malloc(sizeof(T)));
}

template <class T>
static MOZ_ALWAYS_INLINE T* js_pod_calloc() {
  return static_cast<T*>(js_calloc(sizeof(T)));
}

template <class T>
static MOZ_ALWAYS_INLINE T* js_pod_malloc(size_t numElems) {
  size_t bytes;
  if (MOZ_UNLIKELY(!js::CalculateAllocSize<T>(numElems, &bytes)))
    return nullptr;
  return static_cast<T*>(js_malloc(bytes));
}

template <class T>
static MOZ_ALWAYS_INLINE T* js_pod_calloc(size_t numElems) {
  size_t bytes;
  if (MOZ_UNLIKELY(!js::CalculateAllocSize<T>(numElems, &bytes)))
    return nullptr;
  return static_cast<T*>(js_calloc(bytes));
}

template <class T>
static MOZ_ALWAYS_INLINE T* js_pod_realloc(T* prior, size_t oldSize,
                                           size_t newSize) {
  MOZ_ASSERT(!(oldSize & mozilla::tl::MulOverflowMask<sizeof(T)>::value));
  size_t bytes;
  if (MOZ_UNLIKELY(!js::CalculateAllocSize<T>(newSize, &bytes))) return nullptr;
  return static_cast<T*>(js_realloc(prior, bytes));
}

namespace js {

template <typename T>
struct ScopedFreePtrTraits {
  typedef T* type;
  static T* empty() { return nullptr; }
  static void release(T* ptr) { js_free(ptr); }
};
SCOPED_TEMPLATE(ScopedJSFreePtr, ScopedFreePtrTraits)

template <typename T>
struct ScopedDeletePtrTraits : public ScopedFreePtrTraits<T> {
  static void release(T* ptr) { js_delete(ptr); }
};
SCOPED_TEMPLATE(ScopedJSDeletePtr, ScopedDeletePtrTraits)

template <typename T>
struct ScopedReleasePtrTraits : public ScopedFreePtrTraits<T> {
  static void release(T* ptr) {
    if (ptr) ptr->release();
  }
};
SCOPED_TEMPLATE(ScopedReleasePtr, ScopedReleasePtrTraits)

} /* namespace js */

namespace JS {

template <typename T>
struct DeletePolicy {
  constexpr DeletePolicy() {}

  template <typename U>
  MOZ_IMPLICIT DeletePolicy(
      DeletePolicy<U> other,
      typename mozilla::EnableIf<mozilla::IsConvertible<U*, T*>::value,
                                 int>::Type dummy = 0) {}

  void operator()(const T* ptr) { js_delete(const_cast<T*>(ptr)); }
};

struct FreePolicy {
  void operator()(const void* ptr) { js_free(const_cast<void*>(ptr)); }
};

typedef mozilla::UniquePtr<char[], JS::FreePolicy> UniqueChars;
typedef mozilla::UniquePtr<char16_t[], JS::FreePolicy> UniqueTwoByteChars;

}  // namespace JS

namespace js {

/* Integral types for all hash functions. */
typedef uint32_t HashNumber;
const unsigned HashNumberSizeBits = 32;

namespace detail {

/*
 * Given a raw hash code, h, return a number that can be used to select a hash
 * bucket.
 *
 * This function aims to produce as uniform an output distribution as possible,
 * especially in the most significant (leftmost) bits, even though the input
 * distribution may be highly nonrandom, given the constraints that this must
 * be deterministic and quick to compute.
 *
 * Since the leftmost bits of the result are best, the hash bucket index is
 * computed by doing ScrambleHashCode(h) / (2^32/N) or the equivalent
 * right-shift, not ScrambleHashCode(h) % N or the equivalent bit-mask.
 *
 * FIXME: OrderedHashTable uses a bit-mask; see bug 775896.
 */
inline HashNumber ScrambleHashCode(HashNumber h) {
  /*
   * Simply returning h would not cause any hash tables to produce wrong
   * answers. But it can produce pathologically bad performance: The caller
   * right-shifts the result, keeping only the highest bits. The high bits of
   * hash codes are very often completely entropy-free. (So are the lowest
   * bits.)
   *
   * So we use Fibonacci hashing, as described in Knuth, The Art of Computer
   * Programming, 6.4. This mixes all the bits of the input hash code h.
   *
   * The value of goldenRatio is taken from the hex
   * expansion of the golden ratio, which starts 1.9E3779B9....
   * This value is especially good if values with consecutive hash codes
   * are stored in a hash table; see Knuth for details.
   */
  static const HashNumber goldenRatio = 0x9E3779B9U;
  return mozilla::WrappingMultiply(h, goldenRatio);
}

} /* namespace detail */

} /* namespace js */

/* sixgill annotation defines */
#ifndef HAVE_STATIC_ANNOTATIONS
#define HAVE_STATIC_ANNOTATIONS
#ifdef XGILL_PLUGIN
#define STATIC_PRECONDITION(COND) __attribute__((precondition(#COND)))
#define STATIC_PRECONDITION_ASSUME(COND) \
  __attribute__((precondition_assume(#COND)))
#define STATIC_POSTCONDITION(COND) __attribute__((postcondition(#COND)))
#define STATIC_POSTCONDITION_ASSUME(COND) \
  __attribute__((postcondition_assume(#COND)))
#define STATIC_INVARIANT(COND) __attribute__((invariant(#COND)))
#define STATIC_INVARIANT_ASSUME(COND) __attribute__((invariant_assume(#COND)))
#define STATIC_ASSUME(COND)                                          \
  JS_BEGIN_MACRO                                                     \
    __attribute__((assume_static(#COND), unused)) int STATIC_PASTE1( \
        assume_static_, __COUNTER__);                                \
  JS_END_MACRO
#else                                     /* XGILL_PLUGIN */
#define STATIC_PRECONDITION(COND)         /* nothing */
#define STATIC_PRECONDITION_ASSUME(COND)  /* nothing */
#define STATIC_POSTCONDITION(COND)        /* nothing */
#define STATIC_POSTCONDITION_ASSUME(COND) /* nothing */
#define STATIC_INVARIANT(COND)            /* nothing */
#define STATIC_INVARIANT_ASSUME(COND)     /* nothing */
#define STATIC_ASSUME(COND)    \
  JS_BEGIN_MACRO /* nothing */ \
  JS_END_MACRO
#endif /* XGILL_PLUGIN */
#define STATIC_SKIP_INFERENCE STATIC_INVARIANT(skip_inference())
#endif /* HAVE_STATIC_ANNOTATIONS */

#endif /* js_Utility_h */