1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/js/src/jsutil.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,362 @@
1.4 +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
1.5 + * vim: set ts=8 sts=4 et sw=4 tw=99:
1.6 + * This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +/*
1.11 + * PR assertion checker.
1.12 + */
1.13 +
1.14 +#ifndef jsutil_h
1.15 +#define jsutil_h
1.16 +
1.17 +#include "mozilla/Assertions.h"
1.18 +#include "mozilla/Compiler.h"
1.19 +#include "mozilla/GuardObjects.h"
1.20 +
1.21 +#include <limits.h>
1.22 +
1.23 +#include "js/Utility.h"
1.24 +
1.25 +#define JS_ALWAYS_TRUE(expr) MOZ_ALWAYS_TRUE(expr)
1.26 +#define JS_ALWAYS_FALSE(expr) MOZ_ALWAYS_FALSE(expr)
1.27 +
1.28 +#if defined(JS_DEBUG)
1.29 +# define JS_DIAGNOSTICS_ASSERT(expr) MOZ_ASSERT(expr)
1.30 +#elif defined(JS_CRASH_DIAGNOSTICS)
1.31 +# define JS_DIAGNOSTICS_ASSERT(expr) do { if (MOZ_UNLIKELY(!(expr))) MOZ_CRASH(); } while(0)
1.32 +#else
1.33 +# define JS_DIAGNOSTICS_ASSERT(expr) ((void) 0)
1.34 +#endif
1.35 +
1.36 +static MOZ_ALWAYS_INLINE void *
1.37 +js_memcpy(void *dst_, const void *src_, size_t len)
1.38 +{
1.39 + char *dst = (char *) dst_;
1.40 + const char *src = (const char *) src_;
1.41 + JS_ASSERT_IF(dst >= src, (size_t) (dst - src) >= len);
1.42 + JS_ASSERT_IF(src >= dst, (size_t) (src - dst) >= len);
1.43 +
1.44 + return memcpy(dst, src, len);
1.45 +}
1.46 +
1.47 +namespace js {
1.48 +
1.49 +template <class T>
1.50 +struct AlignmentTestStruct
1.51 +{
1.52 + char c;
1.53 + T t;
1.54 +};
1.55 +
1.56 +/* This macro determines the alignment requirements of a type. */
1.57 +#define JS_ALIGNMENT_OF(t_) \
1.58 + (sizeof(js::AlignmentTestStruct<t_>) - sizeof(t_))
1.59 +
1.60 +template <class T>
1.61 +class AlignedPtrAndFlag
1.62 +{
1.63 + uintptr_t bits;
1.64 +
1.65 + public:
1.66 + AlignedPtrAndFlag(T *t, bool aFlag) {
1.67 + JS_ASSERT((uintptr_t(t) & 1) == 0);
1.68 + bits = uintptr_t(t) | uintptr_t(aFlag);
1.69 + }
1.70 +
1.71 + T *ptr() const {
1.72 + return (T *)(bits & ~uintptr_t(1));
1.73 + }
1.74 +
1.75 + bool flag() const {
1.76 + return (bits & 1) != 0;
1.77 + }
1.78 +
1.79 + void setPtr(T *t) {
1.80 + JS_ASSERT((uintptr_t(t) & 1) == 0);
1.81 + bits = uintptr_t(t) | uintptr_t(flag());
1.82 + }
1.83 +
1.84 + void setFlag() {
1.85 + bits |= 1;
1.86 + }
1.87 +
1.88 + void unsetFlag() {
1.89 + bits &= ~uintptr_t(1);
1.90 + }
1.91 +
1.92 + void set(T *t, bool aFlag) {
1.93 + JS_ASSERT((uintptr_t(t) & 1) == 0);
1.94 + bits = uintptr_t(t) | aFlag;
1.95 + }
1.96 +};
1.97 +
1.98 +template <class T>
1.99 +static inline void
1.100 +Reverse(T *beg, T *end)
1.101 +{
1.102 + while (beg != end) {
1.103 + if (--end == beg)
1.104 + return;
1.105 + T tmp = *beg;
1.106 + *beg = *end;
1.107 + *end = tmp;
1.108 + ++beg;
1.109 + }
1.110 +}
1.111 +
1.112 +template <class T>
1.113 +static inline T *
1.114 +Find(T *beg, T *end, const T &v)
1.115 +{
1.116 + for (T *p = beg; p != end; ++p) {
1.117 + if (*p == v)
1.118 + return p;
1.119 + }
1.120 + return end;
1.121 +}
1.122 +
1.123 +template <class Container>
1.124 +static inline typename Container::ElementType *
1.125 +Find(Container &c, const typename Container::ElementType &v)
1.126 +{
1.127 + return Find(c.begin(), c.end(), v);
1.128 +}
1.129 +
1.130 +template <typename InputIterT, typename CallableT>
1.131 +void
1.132 +ForEach(InputIterT begin, InputIterT end, CallableT f)
1.133 +{
1.134 + for (; begin != end; ++begin)
1.135 + f(*begin);
1.136 +}
1.137 +
1.138 +template <class T>
1.139 +static inline T
1.140 +Min(T t1, T t2)
1.141 +{
1.142 + return t1 < t2 ? t1 : t2;
1.143 +}
1.144 +
1.145 +template <class T>
1.146 +static inline T
1.147 +Max(T t1, T t2)
1.148 +{
1.149 + return t1 > t2 ? t1 : t2;
1.150 +}
1.151 +
1.152 +/* Allows a const variable to be initialized after its declaration. */
1.153 +template <class T>
1.154 +static T&
1.155 +InitConst(const T &t)
1.156 +{
1.157 + return const_cast<T &>(t);
1.158 +}
1.159 +
1.160 +template <class T, class U>
1.161 +MOZ_ALWAYS_INLINE T &
1.162 +ImplicitCast(U &u)
1.163 +{
1.164 + T &t = u;
1.165 + return t;
1.166 +}
1.167 +
1.168 +template<typename T>
1.169 +class AutoScopedAssign
1.170 +{
1.171 + public:
1.172 + AutoScopedAssign(T *addr, const T &value
1.173 + MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
1.174 + : addr_(addr), old(*addr_)
1.175 + {
1.176 + MOZ_GUARD_OBJECT_NOTIFIER_INIT;
1.177 + *addr_ = value;
1.178 + }
1.179 +
1.180 + ~AutoScopedAssign() { *addr_ = old; }
1.181 +
1.182 + private:
1.183 + MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
1.184 + T *addr_;
1.185 + T old;
1.186 +};
1.187 +
1.188 +template <typename T>
1.189 +static inline bool
1.190 +IsPowerOfTwo(T t)
1.191 +{
1.192 + return t && !(t & (t - 1));
1.193 +}
1.194 +
1.195 +template <typename T, typename U>
1.196 +static inline U
1.197 +ComputeByteAlignment(T bytes, U alignment)
1.198 +{
1.199 + JS_ASSERT(IsPowerOfTwo(alignment));
1.200 + return (alignment - (bytes % alignment)) % alignment;
1.201 +}
1.202 +
1.203 +template <typename T, typename U>
1.204 +static inline T
1.205 +AlignBytes(T bytes, U alignment)
1.206 +{
1.207 + return bytes + ComputeByteAlignment(bytes, alignment);
1.208 +}
1.209 +
1.210 +static MOZ_ALWAYS_INLINE size_t
1.211 +UnsignedPtrDiff(const void *bigger, const void *smaller)
1.212 +{
1.213 + return size_t(bigger) - size_t(smaller);
1.214 +}
1.215 +
1.216 +/*****************************************************************************/
1.217 +
1.218 +/* A bit array is an array of bits represented by an array of words (size_t). */
1.219 +
1.220 +static const size_t BitArrayElementBits = sizeof(size_t) * CHAR_BIT;
1.221 +
1.222 +static inline unsigned
1.223 +NumWordsForBitArrayOfLength(size_t length)
1.224 +{
1.225 + return (length + (BitArrayElementBits - 1)) / BitArrayElementBits;
1.226 +}
1.227 +
1.228 +static inline unsigned
1.229 +BitArrayIndexToWordIndex(size_t length, size_t bitIndex)
1.230 +{
1.231 + unsigned wordIndex = bitIndex / BitArrayElementBits;
1.232 + JS_ASSERT(wordIndex < length);
1.233 + return wordIndex;
1.234 +}
1.235 +
1.236 +static inline size_t
1.237 +BitArrayIndexToWordMask(size_t i)
1.238 +{
1.239 + return size_t(1) << (i % BitArrayElementBits);
1.240 +}
1.241 +
1.242 +static inline bool
1.243 +IsBitArrayElementSet(size_t *array, size_t length, size_t i)
1.244 +{
1.245 + return array[BitArrayIndexToWordIndex(length, i)] & BitArrayIndexToWordMask(i);
1.246 +}
1.247 +
1.248 +static inline bool
1.249 +IsAnyBitArrayElementSet(size_t *array, size_t length)
1.250 +{
1.251 + unsigned numWords = NumWordsForBitArrayOfLength(length);
1.252 + for (unsigned i = 0; i < numWords; ++i) {
1.253 + if (array[i])
1.254 + return true;
1.255 + }
1.256 + return false;
1.257 +}
1.258 +
1.259 +static inline void
1.260 +SetBitArrayElement(size_t *array, size_t length, size_t i)
1.261 +{
1.262 + array[BitArrayIndexToWordIndex(length, i)] |= BitArrayIndexToWordMask(i);
1.263 +}
1.264 +
1.265 +static inline void
1.266 +ClearBitArrayElement(size_t *array, size_t length, size_t i)
1.267 +{
1.268 + array[BitArrayIndexToWordIndex(length, i)] &= ~BitArrayIndexToWordMask(i);
1.269 +}
1.270 +
1.271 +static inline void
1.272 +ClearAllBitArrayElements(size_t *array, size_t length)
1.273 +{
1.274 + for (unsigned i = 0; i < length; ++i)
1.275 + array[i] = 0;
1.276 +}
1.277 +
1.278 +} /* namespace js */
1.279 +
1.280 +/* Crash diagnostics */
1.281 +#ifdef DEBUG
1.282 +# define JS_CRASH_DIAGNOSTICS 1
1.283 +#endif
1.284 +#if defined(JS_CRASH_DIAGNOSTICS) || defined(JS_GC_ZEAL)
1.285 +# define JS_POISON(p, val, size) memset((p), (val), (size))
1.286 +#else
1.287 +# define JS_POISON(p, val, size) ((void) 0)
1.288 +#endif
1.289 +
1.290 +/* Bug 984101: Disable labeled poisoning until we have poison checking. */
1.291 +#define JS_EXTRA_POISON(p, val, size) ((void) 0)
1.292 +
1.293 +/* Basic stats */
1.294 +#ifdef DEBUG
1.295 +# define JS_BASIC_STATS 1
1.296 +#endif
1.297 +#ifdef JS_BASIC_STATS
1.298 +# include <stdio.h>
1.299 +typedef struct JSBasicStats {
1.300 + uint32_t num;
1.301 + uint32_t max;
1.302 + double sum;
1.303 + double sqsum;
1.304 + uint32_t logscale; /* logarithmic scale: 0 (linear), 2, 10 */
1.305 + uint32_t hist[11];
1.306 +} JSBasicStats;
1.307 +# define JS_INIT_STATIC_BASIC_STATS {0,0,0,0,0,{0,0,0,0,0,0,0,0,0,0,0}}
1.308 +# define JS_BASIC_STATS_INIT(bs) memset((bs), 0, sizeof(JSBasicStats))
1.309 +# define JS_BASIC_STATS_ACCUM(bs,val) \
1.310 + JS_BasicStatsAccum(bs, val)
1.311 +# define JS_MeanAndStdDevBS(bs,sigma) \
1.312 + JS_MeanAndStdDev((bs)->num, (bs)->sum, (bs)->sqsum, sigma)
1.313 +extern void
1.314 +JS_BasicStatsAccum(JSBasicStats *bs, uint32_t val);
1.315 +extern double
1.316 +JS_MeanAndStdDev(uint32_t num, double sum, double sqsum, double *sigma);
1.317 +extern void
1.318 +JS_DumpBasicStats(JSBasicStats *bs, const char *title, FILE *fp);
1.319 +extern void
1.320 +JS_DumpHistogram(JSBasicStats *bs, FILE *fp);
1.321 +#else
1.322 +# define JS_BASIC_STATS_ACCUM(bs,val)
1.323 +#endif
1.324 +
1.325 +/* A jsbitmap_t is a long integer that can be used for bitmaps. */
1.326 +typedef size_t jsbitmap;
1.327 +#define JS_BITMAP_NBITS (sizeof(jsbitmap) * CHAR_BIT)
1.328 +#define JS_TEST_BIT(_map,_bit) ((_map)[(_bit)/JS_BITMAP_NBITS] & \
1.329 + (jsbitmap(1)<<((_bit)%JS_BITMAP_NBITS)))
1.330 +#define JS_SET_BIT(_map,_bit) ((_map)[(_bit)/JS_BITMAP_NBITS] |= \
1.331 + (jsbitmap(1)<<((_bit)%JS_BITMAP_NBITS)))
1.332 +#define JS_CLEAR_BIT(_map,_bit) ((_map)[(_bit)/JS_BITMAP_NBITS] &= \
1.333 + ~(jsbitmap(1)<<((_bit)%JS_BITMAP_NBITS)))
1.334 +
1.335 +/* Wrapper for various macros to stop warnings coming from their expansions. */
1.336 +#if defined(__clang__)
1.337 +# define JS_SILENCE_UNUSED_VALUE_IN_EXPR(expr) \
1.338 + JS_BEGIN_MACRO \
1.339 + _Pragma("clang diagnostic push") \
1.340 + /* If these _Pragmas cause warnings for you, try disabling ccache. */ \
1.341 + _Pragma("clang diagnostic ignored \"-Wunused-value\"") \
1.342 + { expr; } \
1.343 + _Pragma("clang diagnostic pop") \
1.344 + JS_END_MACRO
1.345 +#elif MOZ_IS_GCC
1.346 +
1.347 +#if MOZ_GCC_VERSION_AT_LEAST(4, 6, 0)
1.348 +# define JS_SILENCE_UNUSED_VALUE_IN_EXPR(expr) \
1.349 + JS_BEGIN_MACRO \
1.350 + _Pragma("GCC diagnostic push") \
1.351 + _Pragma("GCC diagnostic ignored \"-Wunused-but-set-variable\"") \
1.352 + expr; \
1.353 + _Pragma("GCC diagnostic pop") \
1.354 + JS_END_MACRO
1.355 +#endif
1.356 +#endif
1.357 +
1.358 +#if !defined(JS_SILENCE_UNUSED_VALUE_IN_EXPR)
1.359 +# define JS_SILENCE_UNUSED_VALUE_IN_EXPR(expr) \
1.360 + JS_BEGIN_MACRO \
1.361 + expr; \
1.362 + JS_END_MACRO
1.363 +#endif
1.364 +
1.365 +#endif /* jsutil_h */
