hphp/util/portability.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-present Facebook, Inc. (http://www.facebook.com)  |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16 #pragma once
  17
  18 #include <folly/Likely.h> // defining LIKELY/UNLIKELY is part of this header
  19 #include <folly/Portability.h>
  20 #include <folly/CPortability.h> // FOLLY_DISABLE_ADDRESS_SANITIZER, FOLLY_EXPORT
  21
  22 //////////////////////////////////////////////////////////////////////
  23
  24 /*
  25  * Various macros to make certain things conditional on either
  26  * compiler or architecture.
  27  *
  28  * Currently we don't *really* compile on anything other than gcc or
  29  * sometimes clang, and there are some parts of the code using
  30  * __attribute__ stuff directly, but some things go through these
  31  * macros to make it maybe easier to change later.
  32  */
  33
  34 //////////////////////////////////////////////////////////////////////
  35
  36 // TODO: does clang define __GNUC__ ?
  37 #ifndef __GNUC__
  38 # define __attribute__(x)
  39 #endif
  40
  41 //////////////////////////////////////////////////////////////////////
  42
  43 #ifdef ATTRIBUTE_UNUSED
  44 # undef ATTRIBUTE_UNUSED
  45 #endif
  46 #ifdef ATTRIBUTE_PRINTF
  47 # undef ATTRIBUTE_PRINTF
  48 #endif
  49 #ifdef ATTRIBUTE_PRINTF_STRING
  50 # undef ATTRIBUTE_PRINTF_STRING
  51 #endif
  52
  53 #define ATTRIBUTE_PRINTF_STRING FOLLY_PRINTF_FORMAT
  54
  55 #ifdef _MSC_VER
  56 #define ATTRIBUTE_PRINTF(a1, a2)
  57 #ifndef __thread
  58 # define __thread __declspec(thread)
  59 #endif
  60 #define ATTRIBUTE_UNUSED
  61 #define ATTRIBUTE_USED
  62
  63 #define ALWAYS_INLINE __forceinline
  64 #define EXTERNALLY_VISIBLE
  65 #define FLATTEN
  66 #define NEVER_INLINE __declspec(noinline)
  67 #define UNUSED
  68
  69 #else
  70 #define ATTRIBUTE_PRINTF(a1, a2) \
  71   __attribute__((__format__ (__printf__, a1, a2)))
  72 #define ATTRIBUTE_UNUSED   __attribute__((__unused__))
  73 #define ATTRIBUTE_USED     __attribute__((__used__))
  74 #ifndef NDEBUG
  75 # define FLATTEN           /*nop*/
  76 # define ALWAYS_INLINE     inline
  77 # define INLINE_FLATTEN    inline
  78 #else
  79 # define FLATTEN           __attribute__((__flatten__))
  80 # define ALWAYS_INLINE     inline __attribute__((__always_inline__))
  81 # define INLINE_FLATTEN    inline __attribute__((__always_inline__,__flatten__))
  82 #endif
  83 #define NEVER_INLINE       __attribute__((__noinline__))
  84 #define UNUSED             __attribute__((__unused__))
  85
  86 #endif
  87
  88 #ifdef __clang__
  89 #define NO_OPT [[clang::optnone]]
  90 #define EXTERNALLY_VISIBLE ATTRIBUTE_USED FOLLY_EXPORT
  91 #else
  92 #define NO_OPT __attribute__((__optimize__("O0")))
  93 #define EXTERNALLY_VISIBLE __attribute__((__externally_visible__))
  94 #endif
  95
  96 #if defined(__GNUC__)
  97 # define HHVM_ATTRIBUTE_WEAK __attribute__((__weak__))
  98 #elif defined(__clang__)
  99 # define HHVM_ATTRIBUTE_WEAK __attribute__((__weak_import__))
 100 #else
 101 # define HHVM_ATTRIBUTE_WEAK
 102 #endif
 103
 104 #ifdef __clang__
 105 #define NO_PROFILING
 106 #elif defined(__GNUC__)
 107 #define NO_PROFILING __attribute__((no_profile_instrument_function))
 108 #else
 109 #define NO_PROFILING
 110 #endif
 111
 112 #ifndef NDEBUG
 113 # define DEBUG_ONLY /* nop */
 114 #else
 115 # define DEBUG_ONLY UNUSED
 116 #endif
 117
 118 #ifndef NDEBUG
 119 #define DEBUG_NOEXCEPT
 120 #else
 121 #define DEBUG_NOEXCEPT noexcept
 122 #endif
 123
 124
 125 /*
 126  * AARCH64 needs to create a walkable stack frame for
 127  * getFrameRegs() when a FixupEntry isIndirect()
 128  */
 129 #ifdef __aarch64__
 130 #define AARCH64_WALKABLE_FRAME() asm("" ::: "memory");
 131 #else
 132 #define AARCH64_WALKABLE_FRAME()
 133 #endif
 134
 135
 136 /*
 137  * We need to keep some unreferenced functions from being removed by
 138  * the linker. There is no compile time mechanism for doing this, but
 139  * by putting them in the same section as some other, referenced function
 140  * in the same file, we can keep them around.
 141  *
 142  * So this macro should be used to mark at least one function that is
 143  * referenced, and other functions that are not referenced in the same
 144  * file.
 145  *
 146  * Note: this may not work properly with LTO. We'll revisit when/if we
 147  * move to it.
 148  */
 149 #ifndef __APPLE__
 150 # define KEEP_SECTION \
 151     __attribute__((__section__(".text.keep")))
 152 #else
 153 # define KEEP_SECTION \
 154     __attribute__((__section__(".text,.text.keep")))
 155 #endif
 156
 157 #if defined(__APPLE__)
 158 // OS X has a macro "isset" defined in this header. Force the include so we can
 159 // make sure the macro gets undef'd. (I think this also applies to BSD, but we
 160 // can cross that road when we come to it.)
 161 # include <sys/param.h>
 162 # ifdef isset
 163 #  undef isset
 164 # endif
 165 #endif
 166
 167 //////////////////////////////////////////////////////////////////////
 168 // DECLARE_FRAME_POINTER
 169
 170 #if defined(__x86_64__)
 171
 172 # define DECLARE_FRAME_POINTER(fp) \
 173   auto const fp = (ActRec*) __builtin_frame_address(0)
 174 # define FRAME_POINTER_IS_ACCURATE
 175
 176 #elif defined(_M_X64)
 177
 178 // TODO: FIXME! Without this implemented properly, the JIT
 179 // will fail "pretty spectacularly".
 180 # define DECLARE_FRAME_POINTER(fp) \
 181   always_assert(false);            \
 182   register ActRec* fp = nullptr;
 183
 184 #elif defined(__AARCH64EL__)
 185
 186 # if defined(__clang__)
 187 # define DECLARE_FRAME_POINTER(fp) register ActRec* fp = (ActRec*) \
 188   __builtin_frame_address(0)
 189 #else
 190 # define DECLARE_FRAME_POINTER(fp) register ActRec* fp asm("x29")
 191 #endif
 192
 193 #elif defined(__powerpc64__)
 194
 195 # if defined(__clang__)
 196 #  error Clang implementation not done for PPC64
 197 # endif
 198 # define DECLARE_FRAME_POINTER(fp) \
 199   auto const fp = (ActRec*) __builtin_frame_address(0)
 200 # define FRAME_POINTER_IS_ACCURATE
 201
 202 #else
 203
 204 # error What are the stack and frame pointers called on your architecture?
 205
 206 #endif
 207
 208 //////////////////////////////////////////////////////////////////////
 209 // CALLEE_SAVED_BARRIER
 210
 211 #ifdef _MSC_VER
 212   // Unfortunately, we have no way to tell MSVC to do this, so we'll
 213   // probably have to use a pair of assembly stubs to manage this.
 214   #define CALLEE_SAVED_BARRIER() always_assert(false);
 215 #elif defined (__powerpc64__)
 216  // After gcc 5.4.1 we can't clobber r30 on PPC64 anymore because it's used as
 217  // PIC register.
 218  #if __GNUC__ > 5 || (__GNUC__ == 5 && (__GNUC_MINOR__ >= 4) && \
 219    (__GNUC_PATCHLEVEL__ >= 1))
 220    #define  CALLEE_SAVED_BARRIER()\
 221      asm volatile("" : : : "r2", "r14", "r15", "r16", "r17", "r18", "r19",\
 222                   "r20", "r21", "r22", "r23", "r24", "r25", "r26", "r27", \
 223                   "r28", "r29", "cr2", "cr3", "cr4", "v20", "v21", "v22", \
 224                   "v23", "v24", "v25", "v26", "v27", "v28", "v29", "v30", \
 225                   "v31");
 226  #else
 227   // On gcc versions < 5.4.1 we need to include r30 on barrier as it's not
 228   // saved by gcc.
 229   #define CALLEE_SAVED_BARRIER()\
 230     asm volatile("" : : : "r2", "r14", "r15", "r16", "r17", "r18", "r19",\
 231                  "r20", "r21", "r22", "r23", "r24", "r25", "r26", "r27", \
 232                  "r28", "r29", "r30", "cr2", "cr3", "cr4", "v20", "v21", \
 233                  "v22", "v23", "v24", "v25", "v26", "v27", "v28", "v29", \
 234                  "v30", "v31");
 235  #endif
 236 #elif defined (__AARCH64EL__)
 237   #define CALLEE_SAVED_BARRIER()\
 238     asm volatile("" : : : "x19", "x20", "x21", "x22", "x23", "x24", "x25",\
 239                  "x26", "x27", "x28", \
 240                  "d8", "d9", "d10", "d11", "d12", "d13", "d14", "d15")
 241 #else
 242   #define CALLEE_SAVED_BARRIER()\
 243     asm volatile("" : : : "rbx", "r12", "r13", "r14", "r15");
 244 #endif
 245
 246 //////////////////////////////////////////////////////////////////////
 247
 248 // We reserve the exit status 127 to signal a failure in the
 249 // interpreter. 127 is a valid exit code on all reasonable
 250 // architectures: POSIX requires at least 8 unsigned bits and
 251 // Windows 32 signed bits.
 252 #define HPHP_EXIT_FAILURE 127
 253
 254 //////////////////////////////////////////////////////////////////////
 255
 256 #if FACEBOOK
 257 #define USE_FOLLY_SYMBOLIZER 1
 258 // Linking in libbfd is a gigantic PITA, but if folly symbolizer doesn't
 259 // work on your platform, you'll need to figure it out.
 260 #define HAVE_LIBBFD 1
 261 #endif
 262
 263 #ifndef PACKAGE
 264 // The value doesn't matter, but it must be defined before you include
 265 // bfd.h
 266 #define PACKAGE "hhvm"
 267 #endif
 268
 269 //////////////////////////////////////////////////////////////////////
 270
 271 #ifdef _MSC_VER
 272 # include "hphp/util/portability/fnmatch.h"
 273 # include "hphp/util/portability/glob.h"
 274 # include "hphp/util/portability/rand_r.h"
 275 # include "hphp/util/portability/strfmon.h"
 276 #endif
 277
 278 #if defined(_MSC_VER) && _MSC_FULL_VER <= 190023506 // 2015 Update 1 or below
 279 // MSVC2015 has an issue with getting function pointers to templated functions
 280 // if the expected result type isn't auto. Unfortunately, when I made the
 281 // initial bug report, I oversimplified the use-case, and, while the case I
 282 // reported was indeed fixed in Update 1 RC, none of our actual uses of it were
 283 // fixed.
 284 // This is being tracked at MS as #163251.
 285 # define MSVC_REQUIRE_AUTO_TEMPLATED_OVERLOAD 1
 286 // 2015 RTM doesn't like it when you try to add via a double duration.
 287 // Bug Report: https://connect.microsoft.com/VisualStudio/feedback/details/1839243
 288 # define MSVC_NO_STD_CHRONO_DURATION_DOUBLE_ADD 1
 289 #endif
 290
 291 #ifdef __APPLE__
 292 #define ASM_LOCAL_LABEL(x) "L" x
 293 #else
 294 #define ASM_LOCAL_LABEL(x) ".L" x
 295 #endif
 296