1 // Copyright 2012 the V8 project authors. All rights reserved. 2 // Redistribution and use in source and binary forms, with or without 3 // modification, are permitted provided that the following conditions are 4 // met: 5 // 6 // * Redistributions of source code must retain the above copyright 7 // notice, this list of conditions and the following disclaimer. 8 // * Redistributions in binary form must reproduce the above 9 // copyright notice, this list of conditions and the following 10 // disclaimer in the documentation and/or other materials provided 11 // with the distribution. 12 // * Neither the name of Google Inc. nor the names of its 13 // contributors may be used to endorse or promote products derived 14 // from this software without specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28 #ifndef V8_GLOBALS_H_ 29 #define V8_GLOBALS_H_ 30 31 // Define V8_INFINITY 32 #define V8_INFINITY INFINITY 33 34 // GCC specific stuff 35 #ifdef __GNUC__ 36 37 #define __GNUC_VERSION_FOR_INFTY__ (__GNUC__ * 10000 + __GNUC_MINOR__ * 100) 38 39 // Unfortunately, the INFINITY macro cannot be used with the '-pedantic' 40 // warning flag and certain versions of GCC due to a bug: 41 // http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11931 42 // For now, we use the more involved template-based version from <limits>, but 43 // only when compiling with GCC versions affected by the bug (2.96.x - 4.0.x) 44 // __GNUC_PREREQ is not defined in GCC for Mac OS X, so we define our own macro 45 #if __GNUC_VERSION_FOR_INFTY__ >= 29600 && __GNUC_VERSION_FOR_INFTY__ < 40100 46 #include <limits> 47 #undef V8_INFINITY 48 #define V8_INFINITY std::numeric_limits<double>::infinity() 49 #endif 50 #undef __GNUC_VERSION_FOR_INFTY__ 51 52 #endif // __GNUC__ 53 54 #ifdef _MSC_VER 55 #undef V8_INFINITY 56 #define V8_INFINITY HUGE_VAL 57 #endif 58 59 60 #include "../include/v8stdint.h" 61 62 namespace v8 { 63 namespace internal { 64 65 // Processor architecture detection. For more info on what's defined, see: 66 // http://msdn.microsoft.com/en-us/library/b0084kay.aspx 67 // http://www.agner.org/optimize/calling_conventions.pdf 68 // or with gcc, run: "echo | gcc -E -dM -" 69 #if defined(_M_X64) || defined(__x86_64__) 70 #define V8_HOST_ARCH_X64 1 71 #define V8_HOST_ARCH_64_BIT 1 72 #define V8_HOST_CAN_READ_UNALIGNED 1 73 #elif defined(_M_IX86) || defined(__i386__) 74 #define V8_HOST_ARCH_IA32 1 75 #define V8_HOST_ARCH_32_BIT 1 76 #define V8_HOST_CAN_READ_UNALIGNED 1 77 #elif defined(__ARMEL__) 78 #define V8_HOST_ARCH_ARM 1 79 #define V8_HOST_ARCH_32_BIT 1 80 // Some CPU-OS combinations allow unaligned access on ARM. We assume 81 // that unaligned accesses are not allowed unless the build system 82 // defines the CAN_USE_UNALIGNED_ACCESSES macro to be non-zero. 83 #if CAN_USE_UNALIGNED_ACCESSES 84 #define V8_HOST_CAN_READ_UNALIGNED 1 85 #endif 86 #elif defined(__MIPSEL__) 87 #define V8_HOST_ARCH_MIPS 1 88 #define V8_HOST_ARCH_32_BIT 1 89 #else 90 #error Host architecture was not detected as supported by v8 91 #endif 92 93 // Target architecture detection. This may be set externally. If not, detect 94 // in the same way as the host architecture, that is, target the native 95 // environment as presented by the compiler. 96 #if !defined(V8_TARGET_ARCH_X64) && !defined(V8_TARGET_ARCH_IA32) && \ 97 !defined(V8_TARGET_ARCH_ARM) && !defined(V8_TARGET_ARCH_MIPS) 98 #if defined(_M_X64) || defined(__x86_64__) 99 #define V8_TARGET_ARCH_X64 1 100 #elif defined(_M_IX86) || defined(__i386__) 101 #define V8_TARGET_ARCH_IA32 1 102 #elif defined(__ARMEL__) 103 #define V8_TARGET_ARCH_ARM 1 104 #elif defined(__MIPSEL__) 105 #define V8_TARGET_ARCH_MIPS 1 106 #else 107 #error Target architecture was not detected as supported by v8 108 #endif 109 #endif 110 111 // Check for supported combinations of host and target architectures. 112 #if defined(V8_TARGET_ARCH_IA32) && !defined(V8_HOST_ARCH_IA32) 113 #error Target architecture ia32 is only supported on ia32 host 114 #endif 115 #if defined(V8_TARGET_ARCH_X64) && !defined(V8_HOST_ARCH_X64) 116 #error Target architecture x64 is only supported on x64 host 117 #endif 118 #if (defined(V8_TARGET_ARCH_ARM) && \ 119 !(defined(V8_HOST_ARCH_IA32) || defined(V8_HOST_ARCH_ARM))) 120 #error Target architecture arm is only supported on arm and ia32 host 121 #endif 122 #if (defined(V8_TARGET_ARCH_MIPS) && \ 123 !(defined(V8_HOST_ARCH_IA32) || defined(V8_HOST_ARCH_MIPS))) 124 #error Target architecture mips is only supported on mips and ia32 host 125 #endif 126 127 // Determine whether we are running in a simulated environment. 128 // Setting USE_SIMULATOR explicitly from the build script will force 129 // the use of a simulated environment. 130 #if !defined(USE_SIMULATOR) 131 #if (defined(V8_TARGET_ARCH_ARM) && !defined(V8_HOST_ARCH_ARM)) 132 #define USE_SIMULATOR 1 133 #endif 134 #if (defined(V8_TARGET_ARCH_MIPS) && !defined(V8_HOST_ARCH_MIPS)) 135 #define USE_SIMULATOR 1 136 #endif 137 #endif 138 139 // Define unaligned read for the target architectures supporting it. 140 #if defined(V8_TARGET_ARCH_X64) || defined(V8_TARGET_ARCH_IA32) 141 #define V8_TARGET_CAN_READ_UNALIGNED 1 142 #elif V8_TARGET_ARCH_ARM 143 // Some CPU-OS combinations allow unaligned access on ARM. We assume 144 // that unaligned accesses are not allowed unless the build system 145 // defines the CAN_USE_UNALIGNED_ACCESSES macro to be non-zero. 146 #if CAN_USE_UNALIGNED_ACCESSES 147 #define V8_TARGET_CAN_READ_UNALIGNED 1 148 #endif 149 #elif V8_TARGET_ARCH_MIPS 150 #else 151 #error Target architecture is not supported by v8 152 #endif 153 154 // Support for alternative bool type. This is only enabled if the code is 155 // compiled with USE_MYBOOL defined. This catches some nasty type bugs. 156 // For instance, 'bool b = "false";' results in b == true! This is a hidden 157 // source of bugs. 158 // However, redefining the bool type does have some negative impact on some 159 // platforms. It gives rise to compiler warnings (i.e. with 160 // MSVC) in the API header files when mixing code that uses the standard 161 // bool with code that uses the redefined version. 162 // This does not actually belong in the platform code, but needs to be 163 // defined here because the platform code uses bool, and platform.h is 164 // include very early in the main include file. 165 166 #ifdef USE_MYBOOL 167 typedef unsigned int __my_bool__; 168 #define bool __my_bool__ // use 'indirection' to avoid name clashes 169 #endif 170 171 typedef uint8_t byte; 172 typedef byte* Address; 173 174 // Define our own macros for writing 64-bit constants. This is less fragile 175 // than defining __STDC_CONSTANT_MACROS before including <stdint.h>, and it 176 // works on compilers that don't have it (like MSVC). 177 #if V8_HOST_ARCH_64_BIT 178 #if defined(_MSC_VER) 179 #define V8_UINT64_C(x) (x ## UI64) 180 #define V8_INT64_C(x) (x ## I64) 181 #define V8_INTPTR_C(x) (x ## I64) 182 #define V8_PTR_PREFIX "ll" 183 #elif defined(__MINGW64__) 184 #define V8_UINT64_C(x) (x ## ULL) 185 #define V8_INT64_C(x) (x ## LL) 186 #define V8_INTPTR_C(x) (x ## LL) 187 #define V8_PTR_PREFIX "I64" 188 #else 189 #define V8_UINT64_C(x) (x ## UL) 190 #define V8_INT64_C(x) (x ## L) 191 #define V8_INTPTR_C(x) (x ## L) 192 #define V8_PTR_PREFIX "l" 193 #endif 194 #else // V8_HOST_ARCH_64_BIT 195 #define V8_INTPTR_C(x) (x) 196 #define V8_PTR_PREFIX "" 197 #endif // V8_HOST_ARCH_64_BIT 198 199 // The following macro works on both 32 and 64-bit platforms. 200 // Usage: instead of writing 0x1234567890123456 201 // write V8_2PART_UINT64_C(0x12345678,90123456); 202 #define V8_2PART_UINT64_C(a, b) (((static_cast<uint64_t>(a) << 32) + 0x##b##u)) 203 204 #define V8PRIxPTR V8_PTR_PREFIX "x" 205 #define V8PRIdPTR V8_PTR_PREFIX "d" 206 207 // Fix for Mac OS X defining uintptr_t as "unsigned long": 208 #if defined(__APPLE__) && defined(__MACH__) 209 #undef V8PRIxPTR 210 #define V8PRIxPTR "lx" 211 #endif 212 213 #if (defined(__APPLE__) && defined(__MACH__)) || \ 214 defined(__FreeBSD__) || defined(__OpenBSD__) 215 #define USING_BSD_ABI 216 #endif 217 218 // ----------------------------------------------------------------------------- 219 // Constants 220 221 const int KB = 1024; 222 const int MB = KB * KB; 223 const int GB = KB * KB * KB; 224 const int kMaxInt = 0x7FFFFFFF; 225 const int kMinInt = -kMaxInt - 1; 226 227 const uint32_t kMaxUInt32 = 0xFFFFFFFFu; 228 229 const int kCharSize = sizeof(char); // NOLINT 230 const int kShortSize = sizeof(short); // NOLINT 231 const int kIntSize = sizeof(int); // NOLINT 232 const int kDoubleSize = sizeof(double); // NOLINT 233 const int kIntptrSize = sizeof(intptr_t); // NOLINT 234 const int kPointerSize = sizeof(void*); // NOLINT 235 236 const int kDoubleSizeLog2 = 3; 237 238 // Size of the state of a the random number generator. 239 const int kRandomStateSize = 2 * kIntSize; 240 241 #if V8_HOST_ARCH_64_BIT 242 const int kPointerSizeLog2 = 3; 243 const intptr_t kIntptrSignBit = V8_INT64_C(0x8000000000000000); 244 const uintptr_t kUintptrAllBitsSet = V8_UINT64_C(0xFFFFFFFFFFFFFFFF); 245 #else 246 const int kPointerSizeLog2 = 2; 247 const intptr_t kIntptrSignBit = 0x80000000; 248 const uintptr_t kUintptrAllBitsSet = 0xFFFFFFFFu; 249 #endif 250 251 const int kBitsPerByte = 8; 252 const int kBitsPerByteLog2 = 3; 253 const int kBitsPerPointer = kPointerSize * kBitsPerByte; 254 const int kBitsPerInt = kIntSize * kBitsPerByte; 255 256 // IEEE 754 single precision floating point number bit layout. 257 const uint32_t kBinary32SignMask = 0x80000000u; 258 const uint32_t kBinary32ExponentMask = 0x7f800000u; 259 const uint32_t kBinary32MantissaMask = 0x007fffffu; 260 const int kBinary32ExponentBias = 127; 261 const int kBinary32MaxExponent = 0xFE; 262 const int kBinary32MinExponent = 0x01; 263 const int kBinary32MantissaBits = 23; 264 const int kBinary32ExponentShift = 23; 265 266 // Quiet NaNs have bits 51 to 62 set, possibly the sign bit, and no 267 // other bits set. 268 const uint64_t kQuietNaNMask = static_cast<uint64_t>(0xfff) << 51; 269 270 // ASCII/UTF-16 constants 271 // Code-point values in Unicode 4.0 are 21 bits wide. 272 // Code units in UTF-16 are 16 bits wide. 273 typedef uint16_t uc16; 274 typedef int32_t uc32; 275 const int kASCIISize = kCharSize; 276 const int kUC16Size = sizeof(uc16); // NOLINT 277 const uc32 kMaxAsciiCharCode = 0x7f; 278 const uint32_t kMaxAsciiCharCodeU = 0x7fu; 279 280 281 // The expression OFFSET_OF(type, field) computes the byte-offset 282 // of the specified field relative to the containing type. This 283 // corresponds to 'offsetof' (in stddef.h), except that it doesn't 284 // use 0 or NULL, which causes a problem with the compiler warnings 285 // we have enabled (which is also why 'offsetof' doesn't seem to work). 286 // Here we simply use the non-zero value 4, which seems to work. 287 #define OFFSET_OF(type, field) \ 288 (reinterpret_cast<intptr_t>(&(reinterpret_cast<type*>(4)->field)) - 4) 289 290 291 // The expression ARRAY_SIZE(a) is a compile-time constant of type 292 // size_t which represents the number of elements of the given 293 // array. You should only use ARRAY_SIZE on statically allocated 294 // arrays. 295 #define ARRAY_SIZE(a) \ 296 ((sizeof(a) / sizeof(*(a))) / \ 297 static_cast<size_t>(!(sizeof(a) % sizeof(*(a))))) 298 299 300 // The USE(x) template is used to silence C++ compiler warnings 301 // issued for (yet) unused variables (typically parameters). 302 template <typename T> 303 inline void USE(T) { } 304 305 306 // FUNCTION_ADDR(f) gets the address of a C function f. 307 #define FUNCTION_ADDR(f) \ 308 (reinterpret_cast<v8::internal::Address>(reinterpret_cast<intptr_t>(f))) 309 310 311 // FUNCTION_CAST<F>(addr) casts an address into a function 312 // of type F. Used to invoke generated code from within C. 313 template <typename F> 314 F FUNCTION_CAST(Address addr) { 315 return reinterpret_cast<F>(reinterpret_cast<intptr_t>(addr)); 316 } 317 318 319 // A macro to disallow the evil copy constructor and operator= functions 320 // This should be used in the private: declarations for a class 321 #define DISALLOW_COPY_AND_ASSIGN(TypeName) \ 322 TypeName(const TypeName&); \ 323 void operator=(const TypeName&) 324 325 326 // A macro to disallow all the implicit constructors, namely the 327 // default constructor, copy constructor and operator= functions. 328 // 329 // This should be used in the private: declarations for a class 330 // that wants to prevent anyone from instantiating it. This is 331 // especially useful for classes containing only static methods. 332 #define DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName) \ 333 TypeName(); \ 334 DISALLOW_COPY_AND_ASSIGN(TypeName) 335 336 337 // Define used for helping GCC to make better inlining. Don't bother for debug 338 // builds. On GCC 3.4.5 using __attribute__((always_inline)) causes compilation 339 // errors in debug build. 340 #if defined(__GNUC__) && !defined(DEBUG) 341 #if (__GNUC__ >= 4) 342 #define INLINE(header) inline header __attribute__((always_inline)) 343 #define NO_INLINE(header) header __attribute__((noinline)) 344 #else 345 #define INLINE(header) inline __attribute__((always_inline)) header 346 #define NO_INLINE(header) __attribute__((noinline)) header 347 #endif 348 #else 349 #define INLINE(header) inline header 350 #define NO_INLINE(header) header 351 #endif 352 353 354 #if defined(__GNUC__) && __GNUC__ >= 4 355 #define MUST_USE_RESULT __attribute__ ((warn_unused_result)) 356 #else 357 #define MUST_USE_RESULT 358 #endif 359 360 // ----------------------------------------------------------------------------- 361 // Forward declarations for frequently used classes 362 // (sorted alphabetically) 363 364 class FreeStoreAllocationPolicy; 365 template <typename T, class P = FreeStoreAllocationPolicy> class List; 366 367 // ----------------------------------------------------------------------------- 368 // Declarations for use in both the preparser and the rest of V8. 369 370 // The different language modes that V8 implements. ES5 defines two language 371 // modes: an unrestricted mode respectively a strict mode which are indicated by 372 // CLASSIC_MODE respectively STRICT_MODE in the enum. The harmony spec drafts 373 // for the next ES standard specify a new third mode which is called 'extended 374 // mode'. The extended mode is only available if the harmony flag is set. It is 375 // based on the 'strict mode' and adds new functionality to it. This means that 376 // most of the semantics of these two modes coincide. 377 // 378 // In the current draft the term 'base code' is used to refer to code that is 379 // neither in strict nor extended mode. However, the more distinguishing term 380 // 'classic mode' is used in V8 instead to avoid mix-ups. 381 382 enum LanguageMode { 383 CLASSIC_MODE, 384 STRICT_MODE, 385 EXTENDED_MODE 386 }; 387 388 389 // The Strict Mode (ECMA-262 5th edition, 4.2.2). 390 // 391 // This flag is used in the backend to represent the language mode. So far 392 // there is no semantic difference between the strict and the extended mode in 393 // the backend, so both modes are represented by the kStrictMode value. 394 enum StrictModeFlag { 395 kNonStrictMode, 396 kStrictMode 397 }; 398 399 400 } } // namespace v8::internal 401 402 #endif // V8_GLOBALS_H_ 403