1 // Copyright 2010 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 #include "../include/v8stdint.h" 32 33 namespace v8 { 34 namespace internal { 35 36 // Processor architecture detection. For more info on what's defined, see: 37 // http://msdn.microsoft.com/en-us/library/b0084kay.aspx 38 // http://www.agner.org/optimize/calling_conventions.pdf 39 // or with gcc, run: "echo | gcc -E -dM -" 40 #if defined(_M_X64) || defined(__x86_64__) 41 #define V8_HOST_ARCH_X64 1 42 #define V8_HOST_ARCH_64_BIT 1 43 #define V8_HOST_CAN_READ_UNALIGNED 1 44 #elif defined(_M_IX86) || defined(__i386__) 45 #define V8_HOST_ARCH_IA32 1 46 #define V8_HOST_ARCH_32_BIT 1 47 #define V8_HOST_CAN_READ_UNALIGNED 1 48 #elif defined(__ARMEL__) 49 #define V8_HOST_ARCH_ARM 1 50 #define V8_HOST_ARCH_32_BIT 1 51 // Some CPU-OS combinations allow unaligned access on ARM. We assume 52 // that unaligned accesses are not allowed unless the build system 53 // defines the CAN_USE_UNALIGNED_ACCESSES macro to be non-zero. 54 #if CAN_USE_UNALIGNED_ACCESSES 55 #define V8_HOST_CAN_READ_UNALIGNED 1 56 #endif 57 #elif defined(__MIPSEL__) 58 #define V8_HOST_ARCH_MIPS 1 59 #define V8_HOST_ARCH_32_BIT 1 60 #else 61 #error Host architecture was not detected as supported by v8 62 #endif 63 64 // Target architecture detection. This may be set externally. If not, detect 65 // in the same way as the host architecture, that is, target the native 66 // environment as presented by the compiler. 67 #if !defined(V8_TARGET_ARCH_X64) && !defined(V8_TARGET_ARCH_IA32) && \ 68 !defined(V8_TARGET_ARCH_ARM) && !defined(V8_TARGET_ARCH_MIPS) 69 #if defined(_M_X64) || defined(__x86_64__) 70 #define V8_TARGET_ARCH_X64 1 71 #elif defined(_M_IX86) || defined(__i386__) 72 #define V8_TARGET_ARCH_IA32 1 73 #elif defined(__ARMEL__) 74 #define V8_TARGET_ARCH_ARM 1 75 #elif defined(__MIPSEL__) 76 #define V8_TARGET_ARCH_MIPS 1 77 #else 78 #error Target architecture was not detected as supported by v8 79 #endif 80 #endif 81 82 // Check for supported combinations of host and target architectures. 83 #if defined(V8_TARGET_ARCH_IA32) && !defined(V8_HOST_ARCH_IA32) 84 #error Target architecture ia32 is only supported on ia32 host 85 #endif 86 #if defined(V8_TARGET_ARCH_X64) && !defined(V8_HOST_ARCH_X64) 87 #error Target architecture x64 is only supported on x64 host 88 #endif 89 #if (defined(V8_TARGET_ARCH_ARM) && \ 90 !(defined(V8_HOST_ARCH_IA32) || defined(V8_HOST_ARCH_ARM))) 91 #error Target architecture arm is only supported on arm and ia32 host 92 #endif 93 #if (defined(V8_TARGET_ARCH_MIPS) && \ 94 !(defined(V8_HOST_ARCH_IA32) || defined(V8_HOST_ARCH_MIPS))) 95 #error Target architecture mips is only supported on mips and ia32 host 96 #endif 97 98 // Determine whether we are running in a simulated environment. 99 // Setting USE_SIMULATOR explicitly from the build script will force 100 // the use of a simulated environment. 101 #if !defined(USE_SIMULATOR) 102 #if (defined(V8_TARGET_ARCH_ARM) && !defined(V8_HOST_ARCH_ARM)) 103 #define USE_SIMULATOR 1 104 #endif 105 #if (defined(V8_TARGET_ARCH_MIPS) && !defined(V8_HOST_ARCH_MIPS)) 106 #define USE_SIMULATOR 1 107 #endif 108 #endif 109 110 // Define unaligned read for the target architectures supporting it. 111 #if defined(V8_TARGET_ARCH_X64) || defined(V8_TARGET_ARCH_IA32) 112 #define V8_TARGET_CAN_READ_UNALIGNED 1 113 #elif V8_TARGET_ARCH_ARM 114 // Some CPU-OS combinations allow unaligned access on ARM. We assume 115 // that unaligned accesses are not allowed unless the build system 116 // defines the CAN_USE_UNALIGNED_ACCESSES macro to be non-zero. 117 #if CAN_USE_UNALIGNED_ACCESSES 118 #define V8_TARGET_CAN_READ_UNALIGNED 1 119 #endif 120 #elif V8_TARGET_ARCH_MIPS 121 #else 122 #error Target architecture is not supported by v8 123 #endif 124 125 // Support for alternative bool type. This is only enabled if the code is 126 // compiled with USE_MYBOOL defined. This catches some nasty type bugs. 127 // For instance, 'bool b = "false";' results in b == true! This is a hidden 128 // source of bugs. 129 // However, redefining the bool type does have some negative impact on some 130 // platforms. It gives rise to compiler warnings (i.e. with 131 // MSVC) in the API header files when mixing code that uses the standard 132 // bool with code that uses the redefined version. 133 // This does not actually belong in the platform code, but needs to be 134 // defined here because the platform code uses bool, and platform.h is 135 // include very early in the main include file. 136 137 #ifdef USE_MYBOOL 138 typedef unsigned int __my_bool__; 139 #define bool __my_bool__ // use 'indirection' to avoid name clashes 140 #endif 141 142 typedef uint8_t byte; 143 typedef byte* Address; 144 145 // Define our own macros for writing 64-bit constants. This is less fragile 146 // than defining __STDC_CONSTANT_MACROS before including <stdint.h>, and it 147 // works on compilers that don't have it (like MSVC). 148 #if V8_HOST_ARCH_64_BIT 149 #ifdef _MSC_VER 150 #define V8_UINT64_C(x) (x ## UI64) 151 #define V8_INT64_C(x) (x ## I64) 152 #define V8_INTPTR_C(x) (x ## I64) 153 #define V8_PTR_PREFIX "ll" 154 #else // _MSC_VER 155 #define V8_UINT64_C(x) (x ## UL) 156 #define V8_INT64_C(x) (x ## L) 157 #define V8_INTPTR_C(x) (x ## L) 158 #define V8_PTR_PREFIX "l" 159 #endif // _MSC_VER 160 #else // V8_HOST_ARCH_64_BIT 161 #define V8_INTPTR_C(x) (x) 162 #define V8_PTR_PREFIX "" 163 #endif // V8_HOST_ARCH_64_BIT 164 165 // The following macro works on both 32 and 64-bit platforms. 166 // Usage: instead of writing 0x1234567890123456 167 // write V8_2PART_UINT64_C(0x12345678,90123456); 168 #define V8_2PART_UINT64_C(a, b) (((static_cast<uint64_t>(a) << 32) + 0x##b##u)) 169 170 #define V8PRIxPTR V8_PTR_PREFIX "x" 171 #define V8PRIdPTR V8_PTR_PREFIX "d" 172 173 // Fix for Mac OS X defining uintptr_t as "unsigned long": 174 #if defined(__APPLE__) && defined(__MACH__) 175 #undef V8PRIxPTR 176 #define V8PRIxPTR "lx" 177 #endif 178 179 #if (defined(__APPLE__) && defined(__MACH__)) || \ 180 defined(__FreeBSD__) || defined(__OpenBSD__) 181 #define USING_BSD_ABI 182 #endif 183 184 // ----------------------------------------------------------------------------- 185 // Constants 186 187 const int KB = 1024; 188 const int MB = KB * KB; 189 const int GB = KB * KB * KB; 190 const int kMaxInt = 0x7FFFFFFF; 191 const int kMinInt = -kMaxInt - 1; 192 193 const uint32_t kMaxUInt32 = 0xFFFFFFFFu; 194 195 const int kCharSize = sizeof(char); // NOLINT 196 const int kShortSize = sizeof(short); // NOLINT 197 const int kIntSize = sizeof(int); // NOLINT 198 const int kDoubleSize = sizeof(double); // NOLINT 199 const int kIntptrSize = sizeof(intptr_t); // NOLINT 200 const int kPointerSize = sizeof(void*); // NOLINT 201 202 #if V8_HOST_ARCH_64_BIT 203 const int kPointerSizeLog2 = 3; 204 const intptr_t kIntptrSignBit = V8_INT64_C(0x8000000000000000); 205 const uintptr_t kUintptrAllBitsSet = V8_UINT64_C(0xFFFFFFFFFFFFFFFF); 206 #else 207 const int kPointerSizeLog2 = 2; 208 const intptr_t kIntptrSignBit = 0x80000000; 209 const uintptr_t kUintptrAllBitsSet = 0xFFFFFFFFu; 210 #endif 211 212 const int kBitsPerByte = 8; 213 const int kBitsPerByteLog2 = 3; 214 const int kBitsPerPointer = kPointerSize * kBitsPerByte; 215 const int kBitsPerInt = kIntSize * kBitsPerByte; 216 217 // IEEE 754 single precision floating point number bit layout. 218 const uint32_t kBinary32SignMask = 0x80000000u; 219 const uint32_t kBinary32ExponentMask = 0x7f800000u; 220 const uint32_t kBinary32MantissaMask = 0x007fffffu; 221 const int kBinary32ExponentBias = 127; 222 const int kBinary32MaxExponent = 0xFE; 223 const int kBinary32MinExponent = 0x01; 224 const int kBinary32MantissaBits = 23; 225 const int kBinary32ExponentShift = 23; 226 227 // ASCII/UC16 constants 228 // Code-point values in Unicode 4.0 are 21 bits wide. 229 typedef uint16_t uc16; 230 typedef int32_t uc32; 231 const int kASCIISize = kCharSize; 232 const int kUC16Size = sizeof(uc16); // NOLINT 233 const uc32 kMaxAsciiCharCode = 0x7f; 234 const uint32_t kMaxAsciiCharCodeU = 0x7fu; 235 236 237 // The expression OFFSET_OF(type, field) computes the byte-offset 238 // of the specified field relative to the containing type. This 239 // corresponds to 'offsetof' (in stddef.h), except that it doesn't 240 // use 0 or NULL, which causes a problem with the compiler warnings 241 // we have enabled (which is also why 'offsetof' doesn't seem to work). 242 // Here we simply use the non-zero value 4, which seems to work. 243 #define OFFSET_OF(type, field) \ 244 (reinterpret_cast<intptr_t>(&(reinterpret_cast<type*>(4)->field)) - 4) 245 246 247 // The expression ARRAY_SIZE(a) is a compile-time constant of type 248 // size_t which represents the number of elements of the given 249 // array. You should only use ARRAY_SIZE on statically allocated 250 // arrays. 251 #define ARRAY_SIZE(a) \ 252 ((sizeof(a) / sizeof(*(a))) / \ 253 static_cast<size_t>(!(sizeof(a) % sizeof(*(a))))) 254 255 256 // The USE(x) template is used to silence C++ compiler warnings 257 // issued for (yet) unused variables (typically parameters). 258 template <typename T> 259 static inline void USE(T) { } 260 261 262 // FUNCTION_ADDR(f) gets the address of a C function f. 263 #define FUNCTION_ADDR(f) \ 264 (reinterpret_cast<v8::internal::Address>(reinterpret_cast<intptr_t>(f))) 265 266 267 // FUNCTION_CAST<F>(addr) casts an address into a function 268 // of type F. Used to invoke generated code from within C. 269 template <typename F> 270 F FUNCTION_CAST(Address addr) { 271 return reinterpret_cast<F>(reinterpret_cast<intptr_t>(addr)); 272 } 273 274 275 // A macro to disallow the evil copy constructor and operator= functions 276 // This should be used in the private: declarations for a class 277 #define DISALLOW_COPY_AND_ASSIGN(TypeName) \ 278 TypeName(const TypeName&); \ 279 void operator=(const TypeName&) 280 281 282 // A macro to disallow all the implicit constructors, namely the 283 // default constructor, copy constructor and operator= functions. 284 // 285 // This should be used in the private: declarations for a class 286 // that wants to prevent anyone from instantiating it. This is 287 // especially useful for classes containing only static methods. 288 #define DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName) \ 289 TypeName(); \ 290 DISALLOW_COPY_AND_ASSIGN(TypeName) 291 292 293 // Define used for helping GCC to make better inlining. Don't bother for debug 294 // builds. On GCC 3.4.5 using __attribute__((always_inline)) causes compilation 295 // errors in debug build. 296 #if defined(__GNUC__) && !defined(DEBUG) 297 #if (__GNUC__ >= 4) 298 #define INLINE(header) inline header __attribute__((always_inline)) 299 #define NO_INLINE(header) header __attribute__((noinline)) 300 #else 301 #define INLINE(header) inline __attribute__((always_inline)) header 302 #define NO_INLINE(header) __attribute__((noinline)) header 303 #endif 304 #else 305 #define INLINE(header) inline header 306 #define NO_INLINE(header) header 307 #endif 308 309 310 #if defined(__GNUC__) && __GNUC__ >= 4 311 #define MUST_USE_RESULT __attribute__ ((warn_unused_result)) 312 #else 313 #define MUST_USE_RESULT 314 #endif 315 316 // ----------------------------------------------------------------------------- 317 // Forward declarations for frequently used classes 318 // (sorted alphabetically) 319 320 class FreeStoreAllocationPolicy; 321 template <typename T, class P = FreeStoreAllocationPolicy> class List; 322 323 } } // namespace v8::internal 324 325 #endif // V8_GLOBALS_H_ 326