ghc/rts/Linker.c

   1 /* -----------------------------------------------------------------------------
   2  *
   3  * (c) The GHC Team, 2000-2004
   4  *
   5  * RTS Object Linker
   6  *
   7  * ---------------------------------------------------------------------------*/
   8
   9 #if 0
  10 #include "PosixSource.h"
  11 #endif
  12
  13 /* Linux needs _GNU_SOURCE to get RTLD_DEFAULT from <dlfcn.h> and
  14    MREMAP_MAYMOVE from <sys/mman.h>.
  15  */
  16 #ifdef __linux__
  17 #define _GNU_SOURCE
  18 #endif
  19
  20 #include "Rts.h"
  21 #include "RtsFlags.h"
  22 #include "HsFFI.h"
  23 #include "Hash.h"
  24 #include "Linker.h"
  25 #include "LinkerInternals.h"
  26 #include "RtsUtils.h"
  27 #include "Schedule.h"
  28 #include "Storage.h"
  29
  30 #ifdef HAVE_SYS_TYPES_H
  31 #include <sys/types.h>
  32 #endif
  33
  34 #include <stdlib.h>
  35 #include <string.h>
  36
  37 #ifdef HAVE_SYS_STAT_H
  38 #include <sys/stat.h>
  39 #endif
  40
  41 #if defined(HAVE_DLFCN_H)
  42 #include <dlfcn.h>
  43 #endif
  44
  45 #if defined(cygwin32_HOST_OS)
  46 #ifdef HAVE_DIRENT_H
  47 #include <dirent.h>
  48 #endif
  49
  50 #ifdef HAVE_SYS_TIME_H
  51 #include <sys/time.h>
  52 #endif
  53 #include <regex.h>
  54 #include <sys/fcntl.h>
  55 #include <sys/termios.h>
  56 #include <sys/utime.h>
  57 #include <sys/utsname.h>
  58 #include <sys/wait.h>
  59 #endif
  60
  61 #if defined(ia64_HOST_ARCH) || defined(openbsd_HOST_OS) || defined(linux_HOST_OS) || defined(freebsd_HOST_OS)
  62 #define USE_MMAP
  63 #include <fcntl.h>
  64 #include <sys/mman.h>
  65
  66 #if defined(openbsd_HOST_OS) || defined(linux_HOST_OS) || defined(freebsd_HOST_OS)
  67 #ifdef HAVE_UNISTD_H
  68 #include <unistd.h>
  69 #endif
  70 #endif
  71
  72 #endif
  73
  74 #if defined(linux_HOST_OS) || defined(solaris2_HOST_OS) || defined(freebsd_HOST_OS) || defined(netbsd_HOST_OS) || defined(openbsd_HOST_OS)
  75 #  define OBJFORMAT_ELF
  76 #elif defined(cygwin32_HOST_OS) || defined (mingw32_HOST_OS)
  77 #  define OBJFORMAT_PEi386
  78 #  include <windows.h>
  79 #  include <math.h>
  80 #elif defined(darwin_HOST_OS)
  81 #  define OBJFORMAT_MACHO
  82 #  include <mach-o/loader.h>
  83 #  include <mach-o/nlist.h>
  84 #  include <mach-o/reloc.h>
  85 #  include <mach-o/dyld.h>
  86 #if defined(powerpc_HOST_ARCH)
  87 #  include <mach-o/ppc/reloc.h>
  88 #endif
  89 #endif
  90
  91 /* Hash table mapping symbol names to Symbol */
  92 static /*Str*/HashTable *symhash;
  93
  94 /* List of currently loaded objects */
  95 ObjectCode *objects = NULL;     /* initially empty */
  96
  97 #if defined(OBJFORMAT_ELF)
  98 static int ocVerifyImage_ELF    ( ObjectCode* oc );
  99 static int ocGetNames_ELF       ( ObjectCode* oc );
 100 static int ocResolve_ELF        ( ObjectCode* oc );
 101 #if defined(powerpc_HOST_ARCH)
 102 static int ocAllocateJumpIslands_ELF ( ObjectCode* oc );
 103 #endif
 104 #elif defined(OBJFORMAT_PEi386)
 105 static int ocVerifyImage_PEi386 ( ObjectCode* oc );
 106 static int ocGetNames_PEi386    ( ObjectCode* oc );
 107 static int ocResolve_PEi386     ( ObjectCode* oc );
 108 #elif defined(OBJFORMAT_MACHO)
 109 static int ocVerifyImage_MachO    ( ObjectCode* oc );
 110 static int ocGetNames_MachO       ( ObjectCode* oc );
 111 static int ocResolve_MachO        ( ObjectCode* oc );
 112
 113 static int machoGetMisalignment( FILE * );
 114 #ifdef powerpc_HOST_ARCH
 115 static int ocAllocateJumpIslands_MachO ( ObjectCode* oc );
 116 static void machoInitSymbolsWithoutUnderscore( void );
 117 #endif
 118 #endif
 119
 120 #if defined(x86_64_HOST_ARCH)
 121 static void*x86_64_high_symbol( char *lbl, void *addr );
 122 #endif
 123
 124 /* -----------------------------------------------------------------------------
 125  * Built-in symbols from the RTS
 126  */
 127
 128 typedef struct _RtsSymbolVal {
 129     char   *lbl;
 130     void   *addr;
 131 } RtsSymbolVal;
 132
 133
 134 #if !defined(PAR)
 135 #define Maybe_Stable_Names      SymX(mkWeakzh_fast)                     \
 136                                 SymX(makeStableNamezh_fast)             \
 137                                 SymX(finalizzeWeakzh_fast)
 138 #else
 139 /* These are not available in GUM!!! -- HWL */
 140 #define Maybe_Stable_Names
 141 #endif
 142
 143 #if !defined (mingw32_HOST_OS)
 144 #define RTS_POSIX_ONLY_SYMBOLS                  \
 145       SymX(stg_sig_install)                     \
 146       Sym(nocldstop)
 147 #endif
 148
 149 #if defined (cygwin32_HOST_OS)
 150 #define RTS_MINGW_ONLY_SYMBOLS /**/
 151 /* Don't have the ability to read import libs / archives, so
 152  * we have to stupidly list a lot of what libcygwin.a
 153  * exports; sigh.
 154  */
 155 #define RTS_CYGWIN_ONLY_SYMBOLS                 \
 156       SymX(regfree)                             \
 157       SymX(regexec)                             \
 158       SymX(regerror)                            \
 159       SymX(regcomp)                             \
 160       SymX(__errno)                             \
 161       SymX(access)                              \
 162       SymX(chmod)                               \
 163       SymX(chdir)                               \
 164       SymX(close)                               \
 165       SymX(creat)                               \
 166       SymX(dup)                                 \
 167       SymX(dup2)                                \
 168       SymX(fstat)                               \
 169       SymX(fcntl)                               \
 170       SymX(getcwd)                              \
 171       SymX(getenv)                              \
 172       SymX(lseek)                               \
 173       SymX(open)                                \
 174       SymX(fpathconf)                           \
 175       SymX(pathconf)                            \
 176       SymX(stat)                                \
 177       SymX(pow)                                 \
 178       SymX(tanh)                                \
 179       SymX(cosh)                                \
 180       SymX(sinh)                                \
 181       SymX(atan)                                \
 182       SymX(acos)                                \
 183       SymX(asin)                                \
 184       SymX(tan)                                 \
 185       SymX(cos)                                 \
 186       SymX(sin)                                 \
 187       SymX(exp)                                 \
 188       SymX(log)                                 \
 189       SymX(sqrt)                                \
 190       SymX(localtime_r)                         \
 191       SymX(gmtime_r)                            \
 192       SymX(mktime)                              \
 193       Sym(_imp___tzname)                        \
 194       SymX(gettimeofday)                        \
 195       SymX(timezone)                            \
 196       SymX(tcgetattr)                           \
 197       SymX(tcsetattr)                           \
 198       SymX(memcpy)                              \
 199       SymX(memmove)                             \
 200       SymX(realloc)                             \
 201       SymX(malloc)                              \
 202       SymX(free)                                \
 203       SymX(fork)                                \
 204       SymX(lstat)                               \
 205       SymX(isatty)                              \
 206       SymX(mkdir)                               \
 207       SymX(opendir)                             \
 208       SymX(readdir)                             \
 209       SymX(rewinddir)                           \
 210       SymX(closedir)                            \
 211       SymX(link)                                \
 212       SymX(mkfifo)                              \
 213       SymX(pipe)                                \
 214       SymX(read)                                \
 215       SymX(rename)                              \
 216       SymX(rmdir)                               \
 217       SymX(select)                              \
 218       SymX(system)                              \
 219       SymX(write)                               \
 220       SymX(strcmp)                              \
 221       SymX(strcpy)                              \
 222       SymX(strncpy)                             \
 223       SymX(strerror)                            \
 224       SymX(sigaddset)                           \
 225       SymX(sigemptyset)                         \
 226       SymX(sigprocmask)                         \
 227       SymX(umask)                               \
 228       SymX(uname)                               \
 229       SymX(unlink)                              \
 230       SymX(utime)                               \
 231       SymX(waitpid)
 232
 233 #elif !defined(mingw32_HOST_OS)
 234 #define RTS_MINGW_ONLY_SYMBOLS /**/
 235 #define RTS_CYGWIN_ONLY_SYMBOLS /**/
 236 #else /* defined(mingw32_HOST_OS) */
 237 #define RTS_POSIX_ONLY_SYMBOLS  /**/
 238 #define RTS_CYGWIN_ONLY_SYMBOLS /**/
 239
 240 /* Extra syms gen'ed by mingw-2's gcc-3.2: */
 241 #if __GNUC__>=3
 242 #define RTS_MINGW_EXTRA_SYMS                    \
 243       Sym(_imp____mb_cur_max)                   \
 244       Sym(_imp___pctype)
 245 #else
 246 #define RTS_MINGW_EXTRA_SYMS
 247 #endif
 248
 249 /* These are statically linked from the mingw libraries into the ghc
 250    executable, so we have to employ this hack. */
 251 #define RTS_MINGW_ONLY_SYMBOLS                  \
 252       SymX(asyncReadzh_fast)                    \
 253       SymX(asyncWritezh_fast)                   \
 254       SymX(asyncDoProczh_fast)                  \
 255       SymX(memset)                              \
 256       SymX(inet_ntoa)                           \
 257       SymX(inet_addr)                           \
 258       SymX(htonl)                               \
 259       SymX(recvfrom)                            \
 260       SymX(listen)                              \
 261       SymX(bind)                                \
 262       SymX(shutdown)                            \
 263       SymX(connect)                             \
 264       SymX(htons)                               \
 265       SymX(ntohs)                               \
 266       SymX(getservbyname)                       \
 267       SymX(getservbyport)                       \
 268       SymX(getprotobynumber)                    \
 269       SymX(getprotobyname)                      \
 270       SymX(gethostbyname)                       \
 271       SymX(gethostbyaddr)                       \
 272       SymX(gethostname)                         \
 273       SymX(strcpy)                              \
 274       SymX(strncpy)                             \
 275       SymX(abort)                               \
 276       Sym(_alloca)                              \
 277       Sym(isxdigit)                             \
 278       Sym(isupper)                              \
 279       Sym(ispunct)                              \
 280       Sym(islower)                              \
 281       Sym(isspace)                              \
 282       Sym(isprint)                              \
 283       Sym(isdigit)                              \
 284       Sym(iscntrl)                              \
 285       Sym(isalpha)                              \
 286       Sym(isalnum)                              \
 287       SymX(strcmp)                              \
 288       SymX(memmove)                             \
 289       SymX(realloc)                             \
 290       SymX(malloc)                              \
 291       SymX(pow)                                 \
 292       SymX(tanh)                                \
 293       SymX(cosh)                                \
 294       SymX(sinh)                                \
 295       SymX(atan)                                \
 296       SymX(acos)                                \
 297       SymX(asin)                                \
 298       SymX(tan)                                 \
 299       SymX(cos)                                 \
 300       SymX(sin)                                 \
 301       SymX(exp)                                 \
 302       SymX(log)                                 \
 303       SymX(sqrt)                                \
 304       SymX(memcpy)                              \
 305       SymX(rts_InstallConsoleEvent)             \
 306       SymX(rts_ConsoleHandlerDone)              \
 307       Sym(mktime)                               \
 308       Sym(_imp___timezone)                      \
 309       Sym(_imp___tzname)                        \
 310       Sym(_imp___iob)                           \
 311       Sym(_imp___osver)                         \
 312       Sym(localtime)                            \
 313       Sym(gmtime)                               \
 314       Sym(opendir)                              \
 315       Sym(readdir)                              \
 316       Sym(rewinddir)                            \
 317       RTS_MINGW_EXTRA_SYMS                      \
 318       Sym(closedir)
 319 #endif
 320
 321 #if defined(darwin_TARGET_OS) && HAVE_PRINTF_LDBLSTUB
 322 #define RTS_DARWIN_ONLY_SYMBOLS                 \
 323      Sym(asprintf$LDBLStub)                     \
 324      Sym(err$LDBLStub)                          \
 325      Sym(errc$LDBLStub)                         \
 326      Sym(errx$LDBLStub)                         \
 327      Sym(fprintf$LDBLStub)                      \
 328      Sym(fscanf$LDBLStub)                       \
 329      Sym(fwprintf$LDBLStub)                     \
 330      Sym(fwscanf$LDBLStub)                      \
 331      Sym(printf$LDBLStub)                       \
 332      Sym(scanf$LDBLStub)                        \
 333      Sym(snprintf$LDBLStub)                     \
 334      Sym(sprintf$LDBLStub)                      \
 335      Sym(sscanf$LDBLStub)                       \
 336      Sym(strtold$LDBLStub)                      \
 337      Sym(swprintf$LDBLStub)                     \
 338      Sym(swscanf$LDBLStub)                      \
 339      Sym(syslog$LDBLStub)                       \
 340      Sym(vasprintf$LDBLStub)                    \
 341      Sym(verr$LDBLStub)                         \
 342      Sym(verrc$LDBLStub)                        \
 343      Sym(verrx$LDBLStub)                        \
 344      Sym(vfprintf$LDBLStub)                     \
 345      Sym(vfscanf$LDBLStub)                      \
 346      Sym(vfwprintf$LDBLStub)                    \
 347      Sym(vfwscanf$LDBLStub)                     \
 348      Sym(vprintf$LDBLStub)                      \
 349      Sym(vscanf$LDBLStub)                       \
 350      Sym(vsnprintf$LDBLStub)                    \
 351      Sym(vsprintf$LDBLStub)                     \
 352      Sym(vsscanf$LDBLStub)                      \
 353      Sym(vswprintf$LDBLStub)                    \
 354      Sym(vswscanf$LDBLStub)                     \
 355      Sym(vsyslog$LDBLStub)                      \
 356      Sym(vwarn$LDBLStub)                        \
 357      Sym(vwarnc$LDBLStub)                       \
 358      Sym(vwarnx$LDBLStub)                       \
 359      Sym(vwprintf$LDBLStub)                     \
 360      Sym(vwscanf$LDBLStub)                      \
 361      Sym(warn$LDBLStub)                         \
 362      Sym(warnc$LDBLStub)                        \
 363      Sym(warnx$LDBLStub)                        \
 364      Sym(wcstold$LDBLStub)                      \
 365      Sym(wprintf$LDBLStub)                      \
 366      Sym(wscanf$LDBLStub)
 367 #else
 368 #define RTS_DARWIN_ONLY_SYMBOLS
 369 #endif
 370
 371 #ifndef SMP
 372 # define MAIN_CAP_SYM SymX(MainCapability)
 373 #else
 374 # define MAIN_CAP_SYM
 375 #endif
 376
 377 #if !defined(mingw32_HOST_OS)
 378 #define RTS_USER_SIGNALS_SYMBOLS \
 379    SymX(startSignalHandler) \
 380    SymX(setIOManagerPipe)
 381 #else
 382 #define RTS_USER_SIGNALS_SYMBOLS /* nothing */
 383 #endif
 384
 385 #ifdef TABLES_NEXT_TO_CODE
 386 #define RTS_RET_SYMBOLS /* nothing */
 387 #else
 388 #define RTS_RET_SYMBOLS                         \
 389       SymX(stg_enter_ret)                       \
 390       SymX(stg_gc_fun_ret)                      \
 391       SymX(stg_ap_0_ret)                        \
 392       SymX(stg_ap_v_ret)                        \
 393       SymX(stg_ap_f_ret)                        \
 394       SymX(stg_ap_d_ret)                        \
 395       SymX(stg_ap_l_ret)                        \
 396       SymX(stg_ap_n_ret)                        \
 397       SymX(stg_ap_p_ret)                        \
 398       SymX(stg_ap_pv_ret)                       \
 399       SymX(stg_ap_pp_ret)                       \
 400       SymX(stg_ap_ppv_ret)                      \
 401       SymX(stg_ap_ppp_ret)                      \
 402       SymX(stg_ap_pppv_ret)                     \
 403       SymX(stg_ap_pppp_ret)                     \
 404       SymX(stg_ap_ppppp_ret)                    \
 405       SymX(stg_ap_pppppp_ret)
 406 #endif
 407
 408 #define RTS_SYMBOLS                             \
 409       Maybe_Stable_Names                        \
 410       Sym(StgReturn)                            \
 411       SymX(stg_enter_info)                      \
 412       SymX(stg_gc_void_info)                    \
 413       SymX(__stg_gc_enter_1)                    \
 414       SymX(stg_gc_noregs)                       \
 415       SymX(stg_gc_unpt_r1_info)                 \
 416       SymX(stg_gc_unpt_r1)                      \
 417       SymX(stg_gc_unbx_r1_info)                 \
 418       SymX(stg_gc_unbx_r1)                      \
 419       SymX(stg_gc_f1_info)                      \
 420       SymX(stg_gc_f1)                           \
 421       SymX(stg_gc_d1_info)                      \
 422       SymX(stg_gc_d1)                           \
 423       SymX(stg_gc_l1_info)                      \
 424       SymX(stg_gc_l1)                           \
 425       SymX(__stg_gc_fun)                        \
 426       SymX(stg_gc_fun_info)                     \
 427       SymX(stg_gc_gen)                          \
 428       SymX(stg_gc_gen_info)                     \
 429       SymX(stg_gc_gen_hp)                       \
 430       SymX(stg_gc_ut)                           \
 431       SymX(stg_gen_yield)                       \
 432       SymX(stg_yield_noregs)                    \
 433       SymX(stg_yield_to_interpreter)            \
 434       SymX(stg_gen_block)                       \
 435       SymX(stg_block_noregs)                    \
 436       SymX(stg_block_1)                         \
 437       SymX(stg_block_takemvar)                  \
 438       SymX(stg_block_putmvar)                   \
 439       SymX(stg_seq_frame_info)                  \
 440       MAIN_CAP_SYM                              \
 441       SymX(MallocFailHook)                      \
 442       SymX(OnExitHook)                          \
 443       SymX(OutOfHeapHook)                       \
 444       SymX(StackOverflowHook)                   \
 445       SymX(__encodeDouble)                      \
 446       SymX(__encodeFloat)                       \
 447       SymX(addDLL)                              \
 448       SymX(__gmpn_gcd_1)                        \
 449       SymX(__gmpz_cmp)                          \
 450       SymX(__gmpz_cmp_si)                       \
 451       SymX(__gmpz_cmp_ui)                       \
 452       SymX(__gmpz_get_si)                       \
 453       SymX(__gmpz_get_ui)                       \
 454       SymX(__int_encodeDouble)                  \
 455       SymX(__int_encodeFloat)                   \
 456       SymX(andIntegerzh_fast)                   \
 457       SymX(atomicallyzh_fast)                   \
 458       SymX(barf)                                \
 459       SymX(debugBelch)                          \
 460       SymX(errorBelch)                          \
 461       SymX(blockAsyncExceptionszh_fast)         \
 462       SymX(catchzh_fast)                        \
 463       SymX(catchRetryzh_fast)                   \
 464       SymX(catchSTMzh_fast)                     \
 465       SymX(closure_flags)                       \
 466       SymX(cmp_thread)                          \
 467       SymX(cmpIntegerzh_fast)                   \
 468       SymX(cmpIntegerIntzh_fast)                \
 469       SymX(complementIntegerzh_fast)            \
 470       SymX(createAdjustor)                      \
 471       SymX(decodeDoublezh_fast)                 \
 472       SymX(decodeFloatzh_fast)                  \
 473       SymX(defaultsHook)                        \
 474       SymX(delayzh_fast)                        \
 475       SymX(deRefWeakzh_fast)                    \
 476       SymX(deRefStablePtrzh_fast)               \
 477       SymX(divExactIntegerzh_fast)              \
 478       SymX(divModIntegerzh_fast)                \
 479       SymX(forkzh_fast)                         \
 480       SymX(forkProcess)                         \
 481       SymX(forkOS_createThread)                 \
 482       SymX(freeHaskellFunctionPtr)              \
 483       SymX(freeStablePtr)                       \
 484       SymX(gcdIntegerzh_fast)                   \
 485       SymX(gcdIntegerIntzh_fast)                \
 486       SymX(gcdIntzh_fast)                       \
 487       SymX(genSymZh)                            \
 488       SymX(genericRaise)                        \
 489       SymX(getProgArgv)                         \
 490       SymX(getStablePtr)                        \
 491       SymX(hs_init)                             \
 492       SymX(hs_exit)                             \
 493       SymX(hs_set_argv)                         \
 494       SymX(hs_add_root)                         \
 495       SymX(hs_perform_gc)                       \
 496       SymX(hs_free_stable_ptr)                  \
 497       SymX(hs_free_fun_ptr)                     \
 498       SymX(initLinker)                          \
 499       SymX(int2Integerzh_fast)                  \
 500       SymX(integer2Intzh_fast)                  \
 501       SymX(integer2Wordzh_fast)                 \
 502       SymX(isCurrentThreadBoundzh_fast)         \
 503       SymX(isDoubleDenormalized)                \
 504       SymX(isDoubleInfinite)                    \
 505       SymX(isDoubleNaN)                         \
 506       SymX(isDoubleNegativeZero)                \
 507       SymX(isEmptyMVarzh_fast)                  \
 508       SymX(isFloatDenormalized)                 \
 509       SymX(isFloatInfinite)                     \
 510       SymX(isFloatNaN)                          \
 511       SymX(isFloatNegativeZero)                 \
 512       SymX(killThreadzh_fast)                   \
 513       SymX(loadObj)                             \
 514       SymX(lookupSymbol)                        \
 515       SymX(makeStablePtrzh_fast)                \
 516       SymX(minusIntegerzh_fast)                 \
 517       SymX(mkApUpd0zh_fast)                     \
 518       SymX(myThreadIdzh_fast)                   \
 519       SymX(labelThreadzh_fast)                  \
 520       SymX(newArrayzh_fast)                     \
 521       SymX(newBCOzh_fast)                       \
 522       SymX(newByteArrayzh_fast)                 \
 523       SymX_redirect(newCAF, newDynCAF)          \
 524       SymX(newMVarzh_fast)                      \
 525       SymX(newMutVarzh_fast)                    \
 526       SymX(newTVarzh_fast)                      \
 527       SymX(atomicModifyMutVarzh_fast)           \
 528       SymX(newPinnedByteArrayzh_fast)           \
 529       SymX(orIntegerzh_fast)                    \
 530       SymX(performGC)                           \
 531       SymX(performMajorGC)                      \
 532       SymX(plusIntegerzh_fast)                  \
 533       SymX(prog_argc)                           \
 534       SymX(prog_argv)                           \
 535       SymX(putMVarzh_fast)                      \
 536       SymX(quotIntegerzh_fast)                  \
 537       SymX(quotRemIntegerzh_fast)               \
 538       SymX(raisezh_fast)                        \
 539       SymX(raiseIOzh_fast)                      \
 540       SymX(readTVarzh_fast)                     \
 541       SymX(remIntegerzh_fast)                   \
 542       SymX(resetNonBlockingFd)                  \
 543       SymX(resumeThread)                        \
 544       SymX(resolveObjs)                         \
 545       SymX(retryzh_fast)                        \
 546       SymX(rts_apply)                           \
 547       SymX(rts_checkSchedStatus)                \
 548       SymX(rts_eval)                            \
 549       SymX(rts_evalIO)                          \
 550       SymX(rts_evalLazyIO)                      \
 551       SymX(rts_evalStableIO)                    \
 552       SymX(rts_eval_)                           \
 553       SymX(rts_getBool)                         \
 554       SymX(rts_getChar)                         \
 555       SymX(rts_getDouble)                       \
 556       SymX(rts_getFloat)                        \
 557       SymX(rts_getInt)                          \
 558       SymX(rts_getInt32)                        \
 559       SymX(rts_getPtr)                          \
 560       SymX(rts_getFunPtr)                       \
 561       SymX(rts_getStablePtr)                    \
 562       SymX(rts_getThreadId)                     \
 563       SymX(rts_getWord)                         \
 564       SymX(rts_getWord32)                       \
 565       SymX(rts_lock)                            \
 566       SymX(rts_mkBool)                          \
 567       SymX(rts_mkChar)                          \
 568       SymX(rts_mkDouble)                        \
 569       SymX(rts_mkFloat)                         \
 570       SymX(rts_mkInt)                           \
 571       SymX(rts_mkInt16)                         \
 572       SymX(rts_mkInt32)                         \
 573       SymX(rts_mkInt64)                         \
 574       SymX(rts_mkInt8)                          \
 575       SymX(rts_mkPtr)                           \
 576       SymX(rts_mkFunPtr)                        \
 577       SymX(rts_mkStablePtr)                     \
 578       SymX(rts_mkString)                        \
 579       SymX(rts_mkWord)                          \
 580       SymX(rts_mkWord16)                        \
 581       SymX(rts_mkWord32)                        \
 582       SymX(rts_mkWord64)                        \
 583       SymX(rts_mkWord8)                         \
 584       SymX(rts_unlock)                          \
 585       SymX(rtsSupportsBoundThreads)             \
 586       SymX(run_queue_hd)                        \
 587       SymX(__hscore_get_saved_termios)          \
 588       SymX(__hscore_set_saved_termios)          \
 589       SymX(setProgArgv)                         \
 590       SymX(startupHaskell)                      \
 591       SymX(shutdownHaskell)                     \
 592       SymX(shutdownHaskellAndExit)              \
 593       SymX(stable_ptr_table)                    \
 594       SymX(stackOverflow)                       \
 595       SymX(stg_CAF_BLACKHOLE_info)              \
 596       SymX(awakenBlockedQueue)                  \
 597       SymX(stg_CHARLIKE_closure)                \
 598       SymX(stg_EMPTY_MVAR_info)                 \
 599       SymX(stg_IND_STATIC_info)                 \
 600       SymX(stg_INTLIKE_closure)                 \
 601       SymX(stg_MUT_ARR_PTRS_FROZEN_info)        \
 602       SymX(stg_MUT_ARR_PTRS_FROZEN0_info)       \
 603       SymX(stg_WEAK_info)                       \
 604       SymX(stg_ap_0_info)                       \
 605       SymX(stg_ap_v_info)                       \
 606       SymX(stg_ap_f_info)                       \
 607       SymX(stg_ap_d_info)                       \
 608       SymX(stg_ap_l_info)                       \
 609       SymX(stg_ap_n_info)                       \
 610       SymX(stg_ap_p_info)                       \
 611       SymX(stg_ap_pv_info)                      \
 612       SymX(stg_ap_pp_info)                      \
 613       SymX(stg_ap_ppv_info)                     \
 614       SymX(stg_ap_ppp_info)                     \
 615       SymX(stg_ap_pppv_info)                    \
 616       SymX(stg_ap_pppp_info)                    \
 617       SymX(stg_ap_ppppp_info)                   \
 618       SymX(stg_ap_pppppp_info)                  \
 619       SymX(stg_ap_1_upd_info)                   \
 620       SymX(stg_ap_2_upd_info)                   \
 621       SymX(stg_ap_3_upd_info)                   \
 622       SymX(stg_ap_4_upd_info)                   \
 623       SymX(stg_ap_5_upd_info)                   \
 624       SymX(stg_ap_6_upd_info)                   \
 625       SymX(stg_ap_7_upd_info)                   \
 626       SymX(stg_exit)                            \
 627       SymX(stg_sel_0_upd_info)                  \
 628       SymX(stg_sel_10_upd_info)                 \
 629       SymX(stg_sel_11_upd_info)                 \
 630       SymX(stg_sel_12_upd_info)                 \
 631       SymX(stg_sel_13_upd_info)                 \
 632       SymX(stg_sel_14_upd_info)                 \
 633       SymX(stg_sel_15_upd_info)                 \
 634       SymX(stg_sel_1_upd_info)                  \
 635       SymX(stg_sel_2_upd_info)                  \
 636       SymX(stg_sel_3_upd_info)                  \
 637       SymX(stg_sel_4_upd_info)                  \
 638       SymX(stg_sel_5_upd_info)                  \
 639       SymX(stg_sel_6_upd_info)                  \
 640       SymX(stg_sel_7_upd_info)                  \
 641       SymX(stg_sel_8_upd_info)                  \
 642       SymX(stg_sel_9_upd_info)                  \
 643       SymX(stg_upd_frame_info)                  \
 644       SymX(suspendThread)                       \
 645       SymX(takeMVarzh_fast)                     \
 646       SymX(timesIntegerzh_fast)                 \
 647       SymX(tryPutMVarzh_fast)                   \
 648       SymX(tryTakeMVarzh_fast)                  \
 649       SymX(unblockAsyncExceptionszh_fast)       \
 650       SymX(unloadObj)                           \
 651       SymX(unsafeThawArrayzh_fast)              \
 652       SymX(waitReadzh_fast)                     \
 653       SymX(waitWritezh_fast)                    \
 654       SymX(word2Integerzh_fast)                 \
 655       SymX(writeTVarzh_fast)                    \
 656       SymX(xorIntegerzh_fast)                   \
 657       SymX(yieldzh_fast)                        \
 658       RTS_USER_SIGNALS_SYMBOLS
 659
 660 #ifdef SUPPORT_LONG_LONGS
 661 #define RTS_LONG_LONG_SYMS                      \
 662       SymX(int64ToIntegerzh_fast)               \
 663       SymX(word64ToIntegerzh_fast)
 664 #else
 665 #define RTS_LONG_LONG_SYMS /* nothing */
 666 #endif
 667
 668 // 64-bit support functions in libgcc.a
 669 #if defined(__GNUC__) && SIZEOF_VOID_P <= 4
 670 #define RTS_LIBGCC_SYMBOLS                      \
 671       Sym(__divdi3)                             \
 672       Sym(__udivdi3)                            \
 673       Sym(__moddi3)                             \
 674       Sym(__umoddi3)                            \
 675       Sym(__muldi3)                             \
 676       Sym(__ashldi3)                            \
 677       Sym(__ashrdi3)                            \
 678       Sym(__lshrdi3)                            \
 679       Sym(__eprintf)
 680 #elif defined(ia64_HOST_ARCH)
 681 #define RTS_LIBGCC_SYMBOLS                      \
 682       Sym(__divdi3)                             \
 683       Sym(__udivdi3)                            \
 684       Sym(__moddi3)                             \
 685       Sym(__umoddi3)                            \
 686       Sym(__divsf3)                             \
 687       Sym(__divdf3)
 688 #else
 689 #define RTS_LIBGCC_SYMBOLS
 690 #endif
 691
 692 #if defined(darwin_HOST_OS) && defined(powerpc_HOST_ARCH)
 693       // Symbols that don't have a leading underscore
 694       // on Mac OS X. They have to receive special treatment,
 695       // see machoInitSymbolsWithoutUnderscore()
 696 #define RTS_MACHO_NOUNDERLINE_SYMBOLS           \
 697       Sym(saveFP)                               \
 698       Sym(restFP)
 699 #endif
 700
 701 /* entirely bogus claims about types of these symbols */
 702 #define Sym(vvv)  extern void vvv(void);
 703 #define SymX(vvv) /**/
 704 #define SymX_redirect(vvv,xxx) /**/
 705 RTS_SYMBOLS
 706 RTS_RET_SYMBOLS
 707 RTS_LONG_LONG_SYMS
 708 RTS_POSIX_ONLY_SYMBOLS
 709 RTS_MINGW_ONLY_SYMBOLS
 710 RTS_CYGWIN_ONLY_SYMBOLS
 711 RTS_DARWIN_ONLY_SYMBOLS
 712 RTS_LIBGCC_SYMBOLS
 713 #undef Sym
 714 #undef SymX
 715 #undef SymX_redirect
 716
 717 #ifdef LEADING_UNDERSCORE
 718 #define MAYBE_LEADING_UNDERSCORE_STR(s) ("_" s)
 719 #else
 720 #define MAYBE_LEADING_UNDERSCORE_STR(s) (s)
 721 #endif
 722
 723 #define Sym(vvv) { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
 724                     (void*)(&(vvv)) },
 725 #define SymX(vvv) Sym(vvv)
 726
 727 // SymX_redirect allows us to redirect references to one symbol to
 728 // another symbol.  See newCAF/newDynCAF for an example.
 729 #define SymX_redirect(vvv,xxx) \
 730     { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
 731       (void*)(&(xxx)) },
 732
 733 static RtsSymbolVal rtsSyms[] = {
 734       RTS_SYMBOLS
 735       RTS_RET_SYMBOLS
 736       RTS_LONG_LONG_SYMS
 737       RTS_POSIX_ONLY_SYMBOLS
 738       RTS_MINGW_ONLY_SYMBOLS
 739       RTS_CYGWIN_ONLY_SYMBOLS
 740       RTS_LIBGCC_SYMBOLS
 741 #if defined(darwin_HOST_OS) && defined(i386_HOST_ARCH)
 742       // dyld stub code contains references to this,
 743       // but it should never be called because we treat
 744       // lazy pointers as nonlazy.
 745       { "dyld_stub_binding_helper", (void*)0xDEADBEEF },
 746 #endif
 747       { 0, 0 } /* sentinel */
 748 };
 749
 750 /* -----------------------------------------------------------------------------
 751  * Insert symbols into hash tables, checking for duplicates.
 752  */
 753 static void ghciInsertStrHashTable ( char* obj_name,
 754                                      HashTable *table,
 755                                      char* key,
 756                                      void *data
 757                                    )
 758 {
 759    if (lookupHashTable(table, (StgWord)key) == NULL)
 760    {
 761       insertStrHashTable(table, (StgWord)key, data);
 762       return;
 763    }
 764    debugBelch(
 765       "\n\n"
 766       "GHCi runtime linker: fatal error: I found a duplicate definition for symbol\n"
 767       "   %s\n"
 768       "whilst processing object file\n"
 769       "   %s\n"
 770       "This could be caused by:\n"
 771       "   * Loading two different object files which export the same symbol\n"
 772       "   * Specifying the same object file twice on the GHCi command line\n"
 773       "   * An incorrect `package.conf' entry, causing some object to be\n"
 774       "     loaded twice.\n"
 775       "GHCi cannot safely continue in this situation.  Exiting now.  Sorry.\n"
 776       "\n",
 777       (char*)key,
 778       obj_name
 779    );
 780    exit(1);
 781 }
 782
 783
 784 /* -----------------------------------------------------------------------------
 785  * initialize the object linker
 786  */
 787
 788
 789 static int linker_init_done = 0 ;
 790
 791 #if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
 792 static void *dl_prog_handle;
 793 #endif
 794
 795 /* dlopen(NULL,..) doesn't work so we grab libc explicitly */
 796 #if defined(openbsd_HOST_OS)
 797 static void *dl_libc_handle;
 798 #endif
 799
 800 void
 801 initLinker( void )
 802 {
 803     RtsSymbolVal *sym;
 804
 805     /* Make initLinker idempotent, so we can call it
 806        before evey relevant operation; that means we
 807        don't need to initialise the linker separately */
 808     if (linker_init_done == 1) { return; } else {
 809       linker_init_done = 1;
 810     }
 811
 812     symhash = allocStrHashTable();
 813
 814     /* populate the symbol table with stuff from the RTS */
 815     for (sym = rtsSyms; sym->lbl != NULL; sym++) {
 816         ghciInsertStrHashTable("(GHCi built-in symbols)",
 817                                symhash, sym->lbl, sym->addr);
 818     }
 819 #   if defined(OBJFORMAT_MACHO) && defined(powerpc_HOST_ARCH)
 820     machoInitSymbolsWithoutUnderscore();
 821 #   endif
 822
 823 #   if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
 824 #   if defined(RTLD_DEFAULT)
 825     dl_prog_handle = RTLD_DEFAULT;
 826 #   else
 827     dl_prog_handle = dlopen(NULL, RTLD_LAZY);
 828 #   if defined(openbsd_HOST_OS)
 829     dl_libc_handle = dlopen("libc.so", RTLD_LAZY);
 830 #   endif
 831 #   endif /* RTLD_DEFAULT */
 832 #   endif
 833 }
 834
 835 /* -----------------------------------------------------------------------------
 836  *                  Loading DLL or .so dynamic libraries
 837  * -----------------------------------------------------------------------------
 838  *
 839  * Add a DLL from which symbols may be found.  In the ELF case, just
 840  * do RTLD_GLOBAL-style add, so no further messing around needs to
 841  * happen in order that symbols in the loaded .so are findable --
 842  * lookupSymbol() will subsequently see them by dlsym on the program's
 843  * dl-handle.  Returns NULL if success, otherwise ptr to an err msg.
 844  *
 845  * In the PEi386 case, open the DLLs and put handles to them in a
 846  * linked list.  When looking for a symbol, try all handles in the
 847  * list.  This means that we need to load even DLLs that are guaranteed
 848  * to be in the ghc.exe image already, just so we can get a handle
 849  * to give to loadSymbol, so that we can find the symbols.  For such
 850  * libraries, the LoadLibrary call should be a no-op except for returning
 851  * the handle.
 852  *
 853  */
 854
 855 #if defined(OBJFORMAT_PEi386)
 856 /* A record for storing handles into DLLs. */
 857
 858 typedef
 859    struct _OpenedDLL {
 860       char*              name;
 861       struct _OpenedDLL* next;
 862       HINSTANCE instance;
 863    }
 864    OpenedDLL;
 865
 866 /* A list thereof. */
 867 static OpenedDLL* opened_dlls = NULL;
 868 #endif
 869
 870 char *
 871 addDLL( char *dll_name )
 872 {
 873 #  if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
 874    /* ------------------- ELF DLL loader ------------------- */
 875    void *hdl;
 876    char *errmsg;
 877
 878    initLinker();
 879
 880    hdl= dlopen(dll_name, RTLD_NOW | RTLD_GLOBAL);
 881
 882    if (hdl == NULL) {
 883       /* dlopen failed; return a ptr to the error msg. */
 884       errmsg = dlerror();
 885       if (errmsg == NULL) errmsg = "addDLL: unknown error";
 886       return errmsg;
 887    } else {
 888       return NULL;
 889    }
 890    /*NOTREACHED*/
 891
 892 #  elif defined(OBJFORMAT_PEi386)
 893    /* ------------------- Win32 DLL loader ------------------- */
 894
 895    char*      buf;
 896    OpenedDLL* o_dll;
 897    HINSTANCE  instance;
 898
 899    initLinker();
 900
 901    /* debugBelch("\naddDLL; dll_name = `%s'\n", dll_name); */
 902
 903    /* See if we've already got it, and ignore if so. */
 904    for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
 905       if (0 == strcmp(o_dll->name, dll_name))
 906          return NULL;
 907    }
 908
 909    /* The file name has no suffix (yet) so that we can try
 910       both foo.dll and foo.drv
 911
 912       The documentation for LoadLibrary says:
 913         If no file name extension is specified in the lpFileName
 914         parameter, the default library extension .dll is
 915         appended. However, the file name string can include a trailing
 916         point character (.) to indicate that the module name has no
 917         extension. */
 918
 919    buf = stgMallocBytes(strlen(dll_name) + 10, "addDLL");
 920    sprintf(buf, "%s.DLL", dll_name);
 921    instance = LoadLibrary(buf);
 922    if (instance == NULL) {
 923          sprintf(buf, "%s.DRV", dll_name);      // KAA: allow loading of drivers (like winspool.drv)
 924          instance = LoadLibrary(buf);
 925          if (instance == NULL) {
 926                 stgFree(buf);
 927
 928             /* LoadLibrary failed; return a ptr to the error msg. */
 929             return "addDLL: unknown error";
 930          }
 931    }
 932    stgFree(buf);
 933
 934    /* Add this DLL to the list of DLLs in which to search for symbols. */
 935    o_dll = stgMallocBytes( sizeof(OpenedDLL), "addDLL" );
 936    o_dll->name     = stgMallocBytes(1+strlen(dll_name), "addDLL");
 937    strcpy(o_dll->name, dll_name);
 938    o_dll->instance = instance;
 939    o_dll->next     = opened_dlls;
 940    opened_dlls     = o_dll;
 941
 942    return NULL;
 943 #  else
 944    barf("addDLL: not implemented on this platform");
 945 #  endif
 946 }
 947
 948 /* -----------------------------------------------------------------------------
 949  * lookup a symbol in the hash table
 950  */
 951 void *
 952 lookupSymbol( char *lbl )
 953 {
 954     void *val;
 955     initLinker() ;
 956     ASSERT(symhash != NULL);
 957     val = lookupStrHashTable(symhash, lbl);
 958
 959     if (val == NULL) {
 960 #       if defined(OBJFORMAT_ELF)
 961 #       if defined(openbsd_HOST_OS)
 962         val = dlsym(dl_prog_handle, lbl);
 963         return (val != NULL) ? val : dlsym(dl_libc_handle,lbl);
 964 #       elif defined(x86_64_HOST_ARCH)
 965         val = dlsym(dl_prog_handle, lbl);
 966         if (val >= (void *)0x80000000) {
 967             void *new_val;
 968             new_val = x86_64_high_symbol(lbl, val);
 969             IF_DEBUG(linker,debugBelch("lookupSymbol: relocating out of range symbol: %s = %p, now %p\n", lbl, val, new_val));
 970             return new_val;
 971         } else {
 972             return val;
 973         }
 974 #       else /* not openbsd */
 975         return dlsym(dl_prog_handle, lbl);
 976 #       endif
 977 #       elif defined(OBJFORMAT_MACHO)
 978         if(NSIsSymbolNameDefined(lbl)) {
 979             NSSymbol symbol = NSLookupAndBindSymbol(lbl);
 980             return NSAddressOfSymbol(symbol);
 981         } else {
 982             return NULL;
 983         }
 984 #       elif defined(OBJFORMAT_PEi386)
 985         OpenedDLL* o_dll;
 986         void* sym;
 987         for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
 988           /* debugBelch("look in %s for %s\n", o_dll->name, lbl); */
 989            if (lbl[0] == '_') {
 990               /* HACK: if the name has an initial underscore, try stripping
 991                  it off & look that up first. I've yet to verify whether there's
 992                  a Rule that governs whether an initial '_' *should always* be
 993                  stripped off when mapping from import lib name to the DLL name.
 994               */
 995               sym = GetProcAddress(o_dll->instance, (lbl+1));
 996               if (sym != NULL) {
 997                 /*debugBelch("found %s in %s\n", lbl+1,o_dll->name);*/
 998                 return sym;
 999               }
1000            }
1001            sym = GetProcAddress(o_dll->instance, lbl);
1002            if (sym != NULL) {
1003              /*debugBelch("found %s in %s\n", lbl,o_dll->name);*/
1004              return sym;
1005            }
1006         }
1007         return NULL;
1008 #       else
1009         ASSERT(2+2 == 5);
1010         return NULL;
1011 #       endif
1012     } else {
1013         return val;
1014     }
1015 }
1016
1017 static
1018 __attribute((unused))
1019 void *
1020 lookupLocalSymbol( ObjectCode* oc, char *lbl )
1021 {
1022     void *val;
1023     initLinker() ;
1024     val = lookupStrHashTable(oc->lochash, lbl);
1025
1026     if (val == NULL) {
1027         return NULL;
1028     } else {
1029         return val;
1030     }
1031 }
1032
1033
1034 /* -----------------------------------------------------------------------------
1035  * Debugging aid: look in GHCi's object symbol tables for symbols
1036  * within DELTA bytes of the specified address, and show their names.
1037  */
1038 #ifdef DEBUG
1039 void ghci_enquire ( char* addr );
1040
1041 void ghci_enquire ( char* addr )
1042 {
1043    int   i;
1044    char* sym;
1045    char* a;
1046    const int DELTA = 64;
1047    ObjectCode* oc;
1048
1049    initLinker();
1050
1051    for (oc = objects; oc; oc = oc->next) {
1052       for (i = 0; i < oc->n_symbols; i++) {
1053          sym = oc->symbols[i];
1054          if (sym == NULL) continue;
1055          // debugBelch("enquire %p %p\n", sym, oc->lochash);
1056          a = NULL;
1057          if (oc->lochash != NULL) {
1058             a = lookupStrHashTable(oc->lochash, sym);
1059          }
1060          if (a == NULL) {
1061             a = lookupStrHashTable(symhash, sym);
1062          }
1063          if (a == NULL) {
1064              // debugBelch("ghci_enquire: can't find %s\n", sym);
1065          }
1066          else if (addr-DELTA <= a && a <= addr+DELTA) {
1067             debugBelch("%p + %3d  ==  `%s'\n", addr, a - addr, sym);
1068          }
1069       }
1070    }
1071 }
1072 #endif
1073
1074 #ifdef ia64_HOST_ARCH
1075 static unsigned int PLTSize(void);
1076 #endif
1077
1078 /* -----------------------------------------------------------------------------
1079  * Load an obj (populate the global symbol table, but don't resolve yet)
1080  *
1081  * Returns: 1 if ok, 0 on error.
1082  */
1083 HsInt
1084 loadObj( char *path )
1085 {
1086    ObjectCode* oc;
1087    struct stat st;
1088    int r, n;
1089 #ifdef USE_MMAP
1090    int fd, pagesize;
1091    void *map_addr = NULL;
1092 #else
1093    FILE *f;
1094    int misalignment;
1095 #endif
1096    initLinker();
1097
1098    /* debugBelch("loadObj %s\n", path ); */
1099
1100    /* Check that we haven't already loaded this object.
1101       Ignore requests to load multiple times */
1102    {
1103        ObjectCode *o;
1104        int is_dup = 0;
1105        for (o = objects; o; o = o->next) {
1106           if (0 == strcmp(o->fileName, path)) {
1107              is_dup = 1;
1108              break; /* don't need to search further */
1109           }
1110        }
1111        if (is_dup) {
1112           IF_DEBUG(linker, debugBelch(
1113             "GHCi runtime linker: warning: looks like you're trying to load the\n"
1114             "same object file twice:\n"
1115             "   %s\n"
1116             "GHCi will ignore this, but be warned.\n"
1117             , path));
1118           return 1; /* success */
1119        }
1120    }
1121
1122    oc = stgMallocBytes(sizeof(ObjectCode), "loadObj(oc)");
1123
1124 #  if defined(OBJFORMAT_ELF)
1125    oc->formatName = "ELF";
1126 #  elif defined(OBJFORMAT_PEi386)
1127    oc->formatName = "PEi386";
1128 #  elif defined(OBJFORMAT_MACHO)
1129    oc->formatName = "Mach-O";
1130 #  else
1131    stgFree(oc);
1132    barf("loadObj: not implemented on this platform");
1133 #  endif
1134
1135    r = stat(path, &st);
1136    if (r == -1) { return 0; }
1137
1138    /* sigh, strdup() isn't a POSIX function, so do it the long way */
1139    oc->fileName = stgMallocBytes( strlen(path)+1, "loadObj" );
1140    strcpy(oc->fileName, path);
1141
1142    oc->fileSize          = st.st_size;
1143    oc->symbols           = NULL;
1144    oc->sections          = NULL;
1145    oc->lochash           = allocStrHashTable();
1146    oc->proddables        = NULL;
1147
1148    /* chain it onto the list of objects */
1149    oc->next              = objects;
1150    objects               = oc;
1151
1152 #ifdef USE_MMAP
1153 #define ROUND_UP(x,size) ((x + size - 1) & ~(size - 1))
1154
1155    /* On many architectures malloc'd memory isn't executable, so we need to use mmap. */
1156
1157 #if defined(openbsd_HOST_OS)
1158    fd = open(path, O_RDONLY, S_IRUSR);
1159 #else
1160    fd = open(path, O_RDONLY);
1161 #endif
1162    if (fd == -1)
1163       barf("loadObj: can't open `%s'", path);
1164
1165    pagesize = getpagesize();
1166
1167 #ifdef ia64_HOST_ARCH
1168    /* The PLT needs to be right before the object */
1169    n = ROUND_UP(PLTSize(), pagesize);
1170    oc->plt = mmap(NULL, n, PROT_EXEC|PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
1171    if (oc->plt == MAP_FAILED)
1172       barf("loadObj: can't allocate PLT");
1173
1174    oc->pltIndex = 0;
1175    map_addr = oc->plt + n;
1176 #endif
1177
1178    n = ROUND_UP(oc->fileSize, pagesize);
1179
1180    /* Link objects into the lower 2Gb on x86_64.  GHC assumes the
1181     * small memory model on this architecture (see gcc docs,
1182     * -mcmodel=small).
1183     */
1184 #ifdef x86_64_HOST_ARCH
1185 #define EXTRA_MAP_FLAGS MAP_32BIT
1186 #else
1187 #define EXTRA_MAP_FLAGS 0
1188 #endif
1189
1190    oc->image = mmap(map_addr, n, PROT_EXEC|PROT_READ|PROT_WRITE,
1191                     MAP_PRIVATE|EXTRA_MAP_FLAGS, fd, 0);
1192    if (oc->image == MAP_FAILED)
1193       barf("loadObj: can't map `%s'", path);
1194
1195    close(fd);
1196
1197 #else /* !USE_MMAP */
1198
1199    /* load the image into memory */
1200    f = fopen(path, "rb");
1201    if (!f)
1202        barf("loadObj: can't read `%s'", path);
1203
1204 #ifdef darwin_HOST_OS
1205     // In a Mach-O .o file, all sections can and will be misaligned
1206     // if the total size of the headers is not a multiple of the
1207     // desired alignment. This is fine for .o files that only serve
1208     // as input for the static linker, but it's not fine for us,
1209     // as SSE (used by gcc for floating point) and Altivec require
1210     // 16-byte alignment.
1211     // We calculate the correct alignment from the header before
1212     // reading the file, and then we misalign oc->image on purpose so
1213     // that the actual sections end up aligned again.
1214    misalignment = machoGetMisalignment(f);
1215    oc->misalignment = misalignment;
1216 #else
1217    misalignment = 0;
1218 #endif
1219
1220    oc->image = stgMallocBytes(oc->fileSize + misalignment, "loadObj(image)");
1221    oc->image += misalignment;
1222
1223    n = fread ( oc->image, 1, oc->fileSize, f );
1224    if (n != oc->fileSize)
1225       barf("loadObj: error whilst reading `%s'", path);
1226
1227    fclose(f);
1228
1229 #endif /* USE_MMAP */
1230
1231 #  if defined(OBJFORMAT_MACHO) && defined(powerpc_HOST_ARCH)
1232    r = ocAllocateJumpIslands_MachO ( oc );
1233    if (!r) { return r; }
1234 #  elif defined(OBJFORMAT_ELF) && defined(powerpc_HOST_ARCH)
1235    r = ocAllocateJumpIslands_ELF ( oc );
1236    if (!r) { return r; }
1237 #endif
1238
1239    /* verify the in-memory image */
1240 #  if defined(OBJFORMAT_ELF)
1241    r = ocVerifyImage_ELF ( oc );
1242 #  elif defined(OBJFORMAT_PEi386)
1243    r = ocVerifyImage_PEi386 ( oc );
1244 #  elif defined(OBJFORMAT_MACHO)
1245    r = ocVerifyImage_MachO ( oc );
1246 #  else
1247    barf("loadObj: no verify method");
1248 #  endif
1249    if (!r) { return r; }
1250
1251    /* build the symbol list for this image */
1252 #  if defined(OBJFORMAT_ELF)
1253    r = ocGetNames_ELF ( oc );
1254 #  elif defined(OBJFORMAT_PEi386)
1255    r = ocGetNames_PEi386 ( oc );
1256 #  elif defined(OBJFORMAT_MACHO)
1257    r = ocGetNames_MachO ( oc );
1258 #  else
1259    barf("loadObj: no getNames method");
1260 #  endif
1261    if (!r) { return r; }
1262
1263    /* loaded, but not resolved yet */
1264    oc->status = OBJECT_LOADED;
1265
1266    return 1;
1267 }
1268
1269 /* -----------------------------------------------------------------------------
1270  * resolve all the currently unlinked objects in memory
1271  *
1272  * Returns: 1 if ok, 0 on error.
1273  */
1274 HsInt
1275 resolveObjs( void )
1276 {
1277     ObjectCode *oc;
1278     int r;
1279
1280     initLinker();
1281
1282     for (oc = objects; oc; oc = oc->next) {
1283         if (oc->status != OBJECT_RESOLVED) {
1284 #           if defined(OBJFORMAT_ELF)
1285             r = ocResolve_ELF ( oc );
1286 #           elif defined(OBJFORMAT_PEi386)
1287             r = ocResolve_PEi386 ( oc );
1288 #           elif defined(OBJFORMAT_MACHO)
1289             r = ocResolve_MachO ( oc );
1290 #           else
1291             barf("resolveObjs: not implemented on this platform");
1292 #           endif
1293             if (!r) { return r; }
1294             oc->status = OBJECT_RESOLVED;
1295         }
1296     }
1297     return 1;
1298 }
1299
1300 /* -----------------------------------------------------------------------------
1301  * delete an object from the pool
1302  */
1303 HsInt
1304 unloadObj( char *path )
1305 {
1306     ObjectCode *oc, *prev;
1307
1308     ASSERT(symhash != NULL);
1309     ASSERT(objects != NULL);
1310
1311     initLinker();
1312
1313     prev = NULL;
1314     for (oc = objects; oc; prev = oc, oc = oc->next) {
1315         if (!strcmp(oc->fileName,path)) {
1316
1317             /* Remove all the mappings for the symbols within this
1318              * object..
1319              */
1320             {
1321                 int i;
1322                 for (i = 0; i < oc->n_symbols; i++) {
1323                    if (oc->symbols[i] != NULL) {
1324                        removeStrHashTable(symhash, oc->symbols[i], NULL);
1325                    }
1326                 }
1327             }
1328
1329             if (prev == NULL) {
1330                 objects = oc->next;
1331             } else {
1332                 prev->next = oc->next;
1333             }
1334
1335             /* We're going to leave this in place, in case there are
1336                any pointers from the heap into it: */
1337             /* stgFree(oc->image); */
1338             stgFree(oc->fileName);
1339             stgFree(oc->symbols);
1340             stgFree(oc->sections);
1341             /* The local hash table should have been freed at the end
1342                of the ocResolve_ call on it. */
1343             ASSERT(oc->lochash == NULL);
1344             stgFree(oc);
1345             return 1;
1346         }
1347     }
1348
1349     errorBelch("unloadObj: can't find `%s' to unload", path);
1350     return 0;
1351 }
1352
1353 /* -----------------------------------------------------------------------------
1354  * Sanity checking.  For each ObjectCode, maintain a list of address ranges
1355  * which may be prodded during relocation, and abort if we try and write
1356  * outside any of these.
1357  */
1358 static void addProddableBlock ( ObjectCode* oc, void* start, int size )
1359 {
1360    ProddableBlock* pb
1361       = stgMallocBytes(sizeof(ProddableBlock), "addProddableBlock");
1362    /* debugBelch("aPB %p %p %d\n", oc, start, size); */
1363    ASSERT(size > 0);
1364    pb->start      = start;
1365    pb->size       = size;
1366    pb->next       = oc->proddables;
1367    oc->proddables = pb;
1368 }
1369
1370 static void checkProddableBlock ( ObjectCode* oc, void* addr )
1371 {
1372    ProddableBlock* pb;
1373    for (pb = oc->proddables; pb != NULL; pb = pb->next) {
1374       char* s = (char*)(pb->start);
1375       char* e = s + pb->size - 1;
1376       char* a = (char*)addr;
1377       /* Assumes that the biggest fixup involves a 4-byte write.  This
1378          probably needs to be changed to 8 (ie, +7) on 64-bit
1379          plats. */
1380       if (a >= s && (a+3) <= e) return;
1381    }
1382    barf("checkProddableBlock: invalid fixup in runtime linker");
1383 }
1384
1385 /* -----------------------------------------------------------------------------
1386  * Section management.
1387  */
1388 static void addSection ( ObjectCode* oc, SectionKind kind,
1389                          void* start, void* end )
1390 {
1391    Section* s   = stgMallocBytes(sizeof(Section), "addSection");
1392    s->start     = start;
1393    s->end       = end;
1394    s->kind      = kind;
1395    s->next      = oc->sections;
1396    oc->sections = s;
1397    /*
1398    debugBelch("addSection: %p-%p (size %d), kind %d\n",
1399                    start, ((char*)end)-1, end - start + 1, kind );
1400    */
1401 }
1402
1403
1404 /* --------------------------------------------------------------------------
1405  * PowerPC specifics (jump islands)
1406  * ------------------------------------------------------------------------*/
1407
1408 #if defined(powerpc_HOST_ARCH)
1409
1410 /*
1411   ocAllocateJumpIslands
1412
1413   Allocate additional space at the end of the object file image to make room
1414   for jump islands.
1415
1416   PowerPC relative branch instructions have a 24 bit displacement field.
1417   As PPC code is always 4-byte-aligned, this yields a +-32MB range.
1418   If a particular imported symbol is outside this range, we have to redirect
1419   the jump to a short piece of new code that just loads the 32bit absolute
1420   address and jumps there.
1421   This function just allocates space for one 16 byte ppcJumpIsland for every
1422   undefined symbol in the object file. The code for the islands is filled in by
1423   makeJumpIsland below.
1424 */
1425
1426 static int ocAllocateJumpIslands( ObjectCode* oc, int count, int first )
1427 {
1428 #ifdef USE_MMAP
1429   int pagesize, n, m;
1430 #endif
1431   int aligned;
1432   int misalignment = 0;
1433 #if darwin_HOST_OS
1434   misalignment = oc->misalignment;
1435 #endif
1436
1437   if( count > 0 )
1438   {
1439     // round up to the nearest 4
1440     aligned = (oc->fileSize + 3) & ~3;
1441
1442 #ifdef USE_MMAP
1443     #ifndef linux_HOST_OS /* mremap is a linux extension */
1444         #error ocAllocateJumpIslands doesnt want USE_MMAP to be defined
1445     #endif
1446
1447     pagesize = getpagesize();
1448     n = ROUND_UP( oc->fileSize, pagesize );
1449     m = ROUND_UP( aligned + sizeof (ppcJumpIsland) * count, pagesize );
1450
1451     /* The effect of this mremap() call is only the ensure that we have
1452      * a sufficient number of virtually contiguous pages.  As returned from
1453      * mremap, the pages past the end of the file are not backed.  We give
1454      * them a backing by using MAP_FIXED to map in anonymous pages.
1455      */
1456     if( (oc->image = mremap( oc->image, n, m, MREMAP_MAYMOVE )) == MAP_FAILED )
1457     {
1458       errorBelch( "Unable to mremap for Jump Islands\n" );
1459       return 0;
1460     }
1461
1462     if( mmap( oc->image + n, m - n, PROT_READ | PROT_WRITE | PROT_EXEC,
1463               MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, 0, 0 ) == MAP_FAILED )
1464     {
1465       errorBelch( "Unable to mmap( MAP_FIXED ) for Jump Islands\n" );
1466       return 0;
1467     }
1468
1469 #else
1470     oc->image -= misalignment;
1471     oc->image = stgReallocBytes( oc->image,
1472                                  misalignment +
1473                                  aligned + sizeof (ppcJumpIsland) * count,
1474                                  "ocAllocateJumpIslands" );
1475     oc->image += misalignment;
1476 #endif /* USE_MMAP */
1477
1478     oc->jump_islands = (ppcJumpIsland *) (oc->image + aligned);
1479     memset( oc->jump_islands, 0, sizeof (ppcJumpIsland) * count );
1480   }
1481   else
1482     oc->jump_islands = NULL;
1483
1484   oc->island_start_symbol = first;
1485   oc->n_islands = count;
1486
1487   return 1;
1488 }
1489
1490 static unsigned long makeJumpIsland( ObjectCode* oc,
1491                                      unsigned long symbolNumber,
1492                                      unsigned long target )
1493 {
1494   ppcJumpIsland *island;
1495
1496   if( symbolNumber < oc->island_start_symbol ||
1497       symbolNumber - oc->island_start_symbol > oc->n_islands)
1498     return 0;
1499
1500   island = &oc->jump_islands[symbolNumber - oc->island_start_symbol];
1501
1502   // lis r12, hi16(target)
1503   island->lis_r12     = 0x3d80;
1504   island->hi_addr     = target >> 16;
1505
1506   // ori r12, r12, lo16(target)
1507   island->ori_r12_r12 = 0x618c;
1508   island->lo_addr     = target & 0xffff;
1509
1510   // mtctr r12
1511   island->mtctr_r12   = 0x7d8903a6;
1512
1513   // bctr
1514   island->bctr        = 0x4e800420;
1515
1516   return (unsigned long) island;
1517 }
1518
1519 /*
1520    ocFlushInstructionCache
1521
1522    Flush the data & instruction caches.
1523    Because the PPC has split data/instruction caches, we have to
1524    do that whenever we modify code at runtime.
1525  */
1526
1527 static void ocFlushInstructionCache( ObjectCode *oc )
1528 {
1529     int n = (oc->fileSize + sizeof( ppcJumpIsland ) * oc->n_islands + 3) / 4;
1530     unsigned long *p = (unsigned long *) oc->image;
1531
1532     while( n-- )
1533     {
1534         __asm__ volatile ( "dcbf 0,%0\n\t"
1535                            "sync\n\t"
1536                            "icbi 0,%0"
1537                            :
1538                            : "r" (p)
1539                          );
1540         p++;
1541     }
1542     __asm__ volatile ( "sync\n\t"
1543                        "isync"
1544                      );
1545 }
1546 #endif
1547
1548 /* --------------------------------------------------------------------------
1549  * PEi386 specifics (Win32 targets)
1550  * ------------------------------------------------------------------------*/
1551
1552 /* The information for this linker comes from
1553       Microsoft Portable Executable
1554       and Common Object File Format Specification
1555       revision 5.1 January 1998
1556    which SimonM says comes from the MS Developer Network CDs.
1557
1558    It can be found there (on older CDs), but can also be found
1559    online at:
1560
1561       http://www.microsoft.com/hwdev/hardware/PECOFF.asp
1562
1563    (this is Rev 6.0 from February 1999).
1564
1565    Things move, so if that fails, try searching for it via
1566
1567       http://www.google.com/search?q=PE+COFF+specification
1568
1569    The ultimate reference for the PE format is the Winnt.h
1570    header file that comes with the Platform SDKs; as always,
1571    implementations will drift wrt their documentation.
1572
1573    A good background article on the PE format is Matt Pietrek's
1574    March 1994 article in Microsoft System Journal (MSJ)
1575    (Vol.9, No. 3): "Peering Inside the PE: A Tour of the
1576    Win32 Portable Executable File Format." The info in there
1577    has recently been updated in a two part article in
1578    MSDN magazine, issues Feb and March 2002,
1579    "Inside Windows: An In-Depth Look into the Win32 Portable
1580    Executable File Format"
1581
1582    John Levine's book "Linkers and Loaders" contains useful
1583    info on PE too.
1584 */
1585
1586
1587 #if defined(OBJFORMAT_PEi386)
1588
1589
1590
1591 typedef unsigned char  UChar;
1592 typedef unsigned short UInt16;
1593 typedef unsigned int   UInt32;
1594 typedef          int   Int32;
1595
1596
1597 typedef
1598    struct {
1599       UInt16 Machine;
1600       UInt16 NumberOfSections;
1601       UInt32 TimeDateStamp;
1602       UInt32 PointerToSymbolTable;
1603       UInt32 NumberOfSymbols;
1604       UInt16 SizeOfOptionalHeader;
1605       UInt16 Characteristics;
1606    }
1607    COFF_header;
1608
1609 #define sizeof_COFF_header 20
1610
1611
1612 typedef
1613    struct {
1614       UChar  Name[8];
1615       UInt32 VirtualSize;
1616       UInt32 VirtualAddress;
1617       UInt32 SizeOfRawData;
1618       UInt32 PointerToRawData;
1619       UInt32 PointerToRelocations;
1620       UInt32 PointerToLinenumbers;
1621       UInt16 NumberOfRelocations;
1622       UInt16 NumberOfLineNumbers;
1623       UInt32 Characteristics;
1624    }
1625    COFF_section;
1626
1627 #define sizeof_COFF_section 40
1628
1629
1630 typedef
1631    struct {
1632       UChar  Name[8];
1633       UInt32 Value;
1634       UInt16 SectionNumber;
1635       UInt16 Type;
1636       UChar  StorageClass;
1637       UChar  NumberOfAuxSymbols;
1638    }
1639    COFF_symbol;
1640
1641 #define sizeof_COFF_symbol 18
1642
1643
1644 typedef
1645    struct {
1646       UInt32 VirtualAddress;
1647       UInt32 SymbolTableIndex;
1648       UInt16 Type;
1649    }
1650    COFF_reloc;
1651
1652 #define sizeof_COFF_reloc 10
1653
1654
1655 /* From PE spec doc, section 3.3.2 */
1656 /* Note use of MYIMAGE_* since IMAGE_* are already defined in
1657    windows.h -- for the same purpose, but I want to know what I'm
1658    getting, here. */
1659 #define MYIMAGE_FILE_RELOCS_STRIPPED     0x0001
1660 #define MYIMAGE_FILE_EXECUTABLE_IMAGE    0x0002
1661 #define MYIMAGE_FILE_DLL                 0x2000
1662 #define MYIMAGE_FILE_SYSTEM              0x1000
1663 #define MYIMAGE_FILE_BYTES_REVERSED_HI   0x8000
1664 #define MYIMAGE_FILE_BYTES_REVERSED_LO   0x0080
1665 #define MYIMAGE_FILE_32BIT_MACHINE       0x0100
1666
1667 /* From PE spec doc, section 5.4.2 and 5.4.4 */
1668 #define MYIMAGE_SYM_CLASS_EXTERNAL       2
1669 #define MYIMAGE_SYM_CLASS_STATIC         3
1670 #define MYIMAGE_SYM_UNDEFINED            0
1671
1672 /* From PE spec doc, section 4.1 */
1673 #define MYIMAGE_SCN_CNT_CODE             0x00000020
1674 #define MYIMAGE_SCN_CNT_INITIALIZED_DATA 0x00000040
1675 #define MYIMAGE_SCN_LNK_NRELOC_OVFL      0x01000000
1676
1677 /* From PE spec doc, section 5.2.1 */
1678 #define MYIMAGE_REL_I386_DIR32           0x0006
1679 #define MYIMAGE_REL_I386_REL32           0x0014
1680
1681
1682 /* We use myindex to calculate array addresses, rather than
1683    simply doing the normal subscript thing.  That's because
1684    some of the above structs have sizes which are not
1685    a whole number of words.  GCC rounds their sizes up to a
1686    whole number of words, which means that the address calcs
1687    arising from using normal C indexing or pointer arithmetic
1688    are just plain wrong.  Sigh.
1689 */
1690 static UChar *
1691 myindex ( int scale, void* base, int index )
1692 {
1693    return
1694       ((UChar*)base) + scale * index;
1695 }
1696
1697
1698 static void
1699 printName ( UChar* name, UChar* strtab )
1700 {
1701    if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1702       UInt32 strtab_offset = * (UInt32*)(name+4);
1703       debugBelch("%s", strtab + strtab_offset );
1704    } else {
1705       int i;
1706       for (i = 0; i < 8; i++) {
1707          if (name[i] == 0) break;
1708          debugBelch("%c", name[i] );
1709       }
1710    }
1711 }
1712
1713
1714 static void
1715 copyName ( UChar* name, UChar* strtab, UChar* dst, int dstSize )
1716 {
1717    if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1718       UInt32 strtab_offset = * (UInt32*)(name+4);
1719       strncpy ( dst, strtab+strtab_offset, dstSize );
1720       dst[dstSize-1] = 0;
1721    } else {
1722       int i = 0;
1723       while (1) {
1724          if (i >= 8) break;
1725          if (name[i] == 0) break;
1726          dst[i] = name[i];
1727          i++;
1728       }
1729       dst[i] = 0;
1730    }
1731 }
1732
1733
1734 static UChar *
1735 cstring_from_COFF_symbol_name ( UChar* name, UChar* strtab )
1736 {
1737    UChar* newstr;
1738    /* If the string is longer than 8 bytes, look in the
1739       string table for it -- this will be correctly zero terminated.
1740    */
1741    if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1742       UInt32 strtab_offset = * (UInt32*)(name+4);
1743       return ((UChar*)strtab) + strtab_offset;
1744    }
1745    /* Otherwise, if shorter than 8 bytes, return the original,
1746       which by defn is correctly terminated.
1747    */
1748    if (name[7]==0) return name;
1749    /* The annoying case: 8 bytes.  Copy into a temporary
1750       (which is never freed ...)
1751    */
1752    newstr = stgMallocBytes(9, "cstring_from_COFF_symbol_name");
1753    ASSERT(newstr);
1754    strncpy(newstr,name,8);
1755    newstr[8] = 0;
1756    return newstr;
1757 }
1758
1759
1760 /* Just compares the short names (first 8 chars) */
1761 static COFF_section *
1762 findPEi386SectionCalled ( ObjectCode* oc,  char* name )
1763 {
1764    int i;
1765    COFF_header* hdr
1766       = (COFF_header*)(oc->image);
1767    COFF_section* sectab
1768       = (COFF_section*) (
1769            ((UChar*)(oc->image))
1770            + sizeof_COFF_header + hdr->SizeOfOptionalHeader
1771         );
1772    for (i = 0; i < hdr->NumberOfSections; i++) {
1773       UChar* n1;
1774       UChar* n2;
1775       COFF_section* section_i
1776          = (COFF_section*)
1777            myindex ( sizeof_COFF_section, sectab, i );
1778       n1 = (UChar*) &(section_i->Name);
1779       n2 = name;
1780       if (n1[0]==n2[0] && n1[1]==n2[1] && n1[2]==n2[2] &&
1781           n1[3]==n2[3] && n1[4]==n2[4] && n1[5]==n2[5] &&
1782           n1[6]==n2[6] && n1[7]==n2[7])
1783          return section_i;
1784    }
1785
1786    return NULL;
1787 }
1788
1789
1790 static void
1791 zapTrailingAtSign ( UChar* sym )
1792 {
1793 #  define my_isdigit(c) ((c) >= '0' && (c) <= '9')
1794    int i, j;
1795    if (sym[0] == 0) return;
1796    i = 0;
1797    while (sym[i] != 0) i++;
1798    i--;
1799    j = i;
1800    while (j > 0 && my_isdigit(sym[j])) j--;
1801    if (j > 0 && sym[j] == '@' && j != i) sym[j] = 0;
1802 #  undef my_isdigit
1803 }
1804
1805
1806 static int
1807 ocVerifyImage_PEi386 ( ObjectCode* oc )
1808 {
1809    int i;
1810    UInt32 j, noRelocs;
1811    COFF_header*  hdr;
1812    COFF_section* sectab;
1813    COFF_symbol*  symtab;
1814    UChar*        strtab;
1815    /* debugBelch("\nLOADING %s\n", oc->fileName); */
1816    hdr = (COFF_header*)(oc->image);
1817    sectab = (COFF_section*) (
1818                ((UChar*)(oc->image))
1819                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
1820             );
1821    symtab = (COFF_symbol*) (
1822                ((UChar*)(oc->image))
1823                + hdr->PointerToSymbolTable
1824             );
1825    strtab = ((UChar*)symtab)
1826             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
1827
1828    if (hdr->Machine != 0x14c) {
1829       errorBelch("%s: Not x86 PEi386", oc->fileName);
1830       return 0;
1831    }
1832    if (hdr->SizeOfOptionalHeader != 0) {
1833       errorBelch("%s: PEi386 with nonempty optional header", oc->fileName);
1834       return 0;
1835    }
1836    if ( /* (hdr->Characteristics & MYIMAGE_FILE_RELOCS_STRIPPED) || */
1837         (hdr->Characteristics & MYIMAGE_FILE_EXECUTABLE_IMAGE) ||
1838         (hdr->Characteristics & MYIMAGE_FILE_DLL) ||
1839         (hdr->Characteristics & MYIMAGE_FILE_SYSTEM) ) {
1840       errorBelch("%s: Not a PEi386 object file", oc->fileName);
1841       return 0;
1842    }
1843    if ( (hdr->Characteristics & MYIMAGE_FILE_BYTES_REVERSED_HI)
1844         /* || !(hdr->Characteristics & MYIMAGE_FILE_32BIT_MACHINE) */ ) {
1845       errorBelch("%s: Invalid PEi386 word size or endiannness: %d",
1846                  oc->fileName,
1847                  (int)(hdr->Characteristics));
1848       return 0;
1849    }
1850    /* If the string table size is way crazy, this might indicate that
1851       there are more than 64k relocations, despite claims to the
1852       contrary.  Hence this test. */
1853    /* debugBelch("strtab size %d\n", * (UInt32*)strtab); */
1854 #if 0
1855    if ( (*(UInt32*)strtab) > 600000 ) {
1856       /* Note that 600k has no special significance other than being
1857          big enough to handle the almost-2MB-sized lumps that
1858          constitute HSwin32*.o. */
1859       debugBelch("PEi386 object has suspiciously large string table; > 64k relocs?");
1860       return 0;
1861    }
1862 #endif
1863
1864    /* No further verification after this point; only debug printing. */
1865    i = 0;
1866    IF_DEBUG(linker, i=1);
1867    if (i == 0) return 1;
1868
1869    debugBelch( "sectab offset = %d\n", ((UChar*)sectab) - ((UChar*)hdr) );
1870    debugBelch( "symtab offset = %d\n", ((UChar*)symtab) - ((UChar*)hdr) );
1871    debugBelch( "strtab offset = %d\n", ((UChar*)strtab) - ((UChar*)hdr) );
1872
1873    debugBelch("\n" );
1874    debugBelch( "Machine:           0x%x\n", (UInt32)(hdr->Machine) );
1875    debugBelch( "# sections:        %d\n",   (UInt32)(hdr->NumberOfSections) );
1876    debugBelch( "time/date:         0x%x\n", (UInt32)(hdr->TimeDateStamp) );
1877    debugBelch( "symtab offset:     %d\n",   (UInt32)(hdr->PointerToSymbolTable) );
1878    debugBelch( "# symbols:         %d\n",   (UInt32)(hdr->NumberOfSymbols) );
1879    debugBelch( "sz of opt hdr:     %d\n",   (UInt32)(hdr->SizeOfOptionalHeader) );
1880    debugBelch( "characteristics:   0x%x\n", (UInt32)(hdr->Characteristics) );
1881
1882    /* Print the section table. */
1883    debugBelch("\n" );
1884    for (i = 0; i < hdr->NumberOfSections; i++) {
1885       COFF_reloc* reltab;
1886       COFF_section* sectab_i
1887          = (COFF_section*)
1888            myindex ( sizeof_COFF_section, sectab, i );
1889       debugBelch(
1890                 "\n"
1891                 "section %d\n"
1892                 "     name `",
1893                 i
1894               );
1895       printName ( sectab_i->Name, strtab );
1896       debugBelch(
1897                 "'\n"
1898                 "    vsize %d\n"
1899                 "    vaddr %d\n"
1900                 "  data sz %d\n"
1901                 " data off %d\n"
1902                 "  num rel %d\n"
1903                 "  off rel %d\n"
1904                 "  ptr raw 0x%x\n",
1905                 sectab_i->VirtualSize,
1906                 sectab_i->VirtualAddress,
1907                 sectab_i->SizeOfRawData,
1908                 sectab_i->PointerToRawData,
1909                 sectab_i->NumberOfRelocations,
1910                 sectab_i->PointerToRelocations,
1911                 sectab_i->PointerToRawData
1912               );
1913       reltab = (COFF_reloc*) (
1914                   ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
1915                );
1916
1917       if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
1918         /* If the relocation field (a short) has overflowed, the
1919          * real count can be found in the first reloc entry.
1920          *
1921          * See Section 4.1 (last para) of the PE spec (rev6.0).
1922          */
1923         COFF_reloc* rel = (COFF_reloc*)
1924                            myindex ( sizeof_COFF_reloc, reltab, 0 );
1925         noRelocs = rel->VirtualAddress;
1926         j = 1;
1927       } else {
1928         noRelocs = sectab_i->NumberOfRelocations;
1929         j = 0;
1930       }
1931
1932       for (; j < noRelocs; j++) {
1933          COFF_symbol* sym;
1934          COFF_reloc* rel = (COFF_reloc*)
1935                            myindex ( sizeof_COFF_reloc, reltab, j );
1936          debugBelch(
1937                    "        type 0x%-4x   vaddr 0x%-8x   name `",
1938                    (UInt32)rel->Type,
1939                    rel->VirtualAddress );
1940          sym = (COFF_symbol*)
1941                myindex ( sizeof_COFF_symbol, symtab, rel->SymbolTableIndex );
1942          /* Hmm..mysterious looking offset - what's it for? SOF */
1943          printName ( sym->Name, strtab -10 );
1944          debugBelch("'\n" );
1945       }
1946
1947       debugBelch("\n" );
1948    }
1949    debugBelch("\n" );
1950    debugBelch("string table has size 0x%x\n", * (UInt32*)strtab );
1951    debugBelch("---START of string table---\n");
1952    for (i = 4; i < *(Int32*)strtab; i++) {
1953       if (strtab[i] == 0)
1954          debugBelch("\n"); else
1955          debugBelch("%c", strtab[i] );
1956    }
1957    debugBelch("--- END  of string table---\n");
1958
1959    debugBelch("\n" );
1960    i = 0;
1961    while (1) {
1962       COFF_symbol* symtab_i;
1963       if (i >= (Int32)(hdr->NumberOfSymbols)) break;
1964       symtab_i = (COFF_symbol*)
1965                  myindex ( sizeof_COFF_symbol, symtab, i );
1966       debugBelch(
1967                 "symbol %d\n"
1968                 "     name `",
1969                 i
1970               );
1971       printName ( symtab_i->Name, strtab );
1972       debugBelch(
1973                 "'\n"
1974                 "    value 0x%x\n"
1975                 "   1+sec# %d\n"
1976                 "     type 0x%x\n"
1977                 "   sclass 0x%x\n"
1978                 "     nAux %d\n",
1979                 symtab_i->Value,
1980                 (Int32)(symtab_i->SectionNumber),
1981                 (UInt32)symtab_i->Type,
1982                 (UInt32)symtab_i->StorageClass,
1983                 (UInt32)symtab_i->NumberOfAuxSymbols
1984               );
1985       i += symtab_i->NumberOfAuxSymbols;
1986       i++;
1987    }
1988
1989    debugBelch("\n" );
1990    return 1;
1991 }
1992
1993
1994 static int
1995 ocGetNames_PEi386 ( ObjectCode* oc )
1996 {
1997    COFF_header*  hdr;
1998    COFF_section* sectab;
1999    COFF_symbol*  symtab;
2000    UChar*        strtab;
2001
2002    UChar* sname;
2003    void*  addr;
2004    int    i;
2005
2006    hdr = (COFF_header*)(oc->image);
2007    sectab = (COFF_section*) (
2008                ((UChar*)(oc->image))
2009                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2010             );
2011    symtab = (COFF_symbol*) (
2012                ((UChar*)(oc->image))
2013                + hdr->PointerToSymbolTable
2014             );
2015    strtab = ((UChar*)(oc->image))
2016             + hdr->PointerToSymbolTable
2017             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2018
2019    /* Allocate space for any (local, anonymous) .bss sections. */
2020
2021    for (i = 0; i < hdr->NumberOfSections; i++) {
2022       UChar* zspace;
2023       COFF_section* sectab_i
2024          = (COFF_section*)
2025            myindex ( sizeof_COFF_section, sectab, i );
2026       if (0 != strcmp(sectab_i->Name, ".bss")) continue;
2027       if (sectab_i->VirtualSize == 0) continue;
2028       /* This is a non-empty .bss section.  Allocate zeroed space for
2029          it, and set its PointerToRawData field such that oc->image +
2030          PointerToRawData == addr_of_zeroed_space.  */
2031       zspace = stgCallocBytes(1, sectab_i->VirtualSize,
2032                               "ocGetNames_PEi386(anonymous bss)");
2033       sectab_i->PointerToRawData = ((UChar*)zspace) - ((UChar*)(oc->image));
2034       addProddableBlock(oc, zspace, sectab_i->VirtualSize);
2035       /* debugBelch("BSS anon section at 0x%x\n", zspace); */
2036    }
2037
2038    /* Copy section information into the ObjectCode. */
2039
2040    for (i = 0; i < hdr->NumberOfSections; i++) {
2041       UChar* start;
2042       UChar* end;
2043       UInt32 sz;
2044
2045       SectionKind kind
2046          = SECTIONKIND_OTHER;
2047       COFF_section* sectab_i
2048          = (COFF_section*)
2049            myindex ( sizeof_COFF_section, sectab, i );
2050       IF_DEBUG(linker, debugBelch("section name = %s\n", sectab_i->Name ));
2051
2052 #     if 0
2053       /* I'm sure this is the Right Way to do it.  However, the
2054          alternative of testing the sectab_i->Name field seems to
2055          work ok with Cygwin.
2056       */
2057       if (sectab_i->Characteristics & MYIMAGE_SCN_CNT_CODE ||
2058           sectab_i->Characteristics & MYIMAGE_SCN_CNT_INITIALIZED_DATA)
2059          kind = SECTIONKIND_CODE_OR_RODATA;
2060 #     endif
2061
2062       if (0==strcmp(".text",sectab_i->Name) ||
2063           0==strcmp(".rdata",sectab_i->Name)||
2064           0==strcmp(".rodata",sectab_i->Name))
2065          kind = SECTIONKIND_CODE_OR_RODATA;
2066       if (0==strcmp(".data",sectab_i->Name) ||
2067           0==strcmp(".bss",sectab_i->Name))
2068          kind = SECTIONKIND_RWDATA;
2069
2070       ASSERT(sectab_i->SizeOfRawData == 0 || sectab_i->VirtualSize == 0);
2071       sz = sectab_i->SizeOfRawData;
2072       if (sz < sectab_i->VirtualSize) sz = sectab_i->VirtualSize;
2073
2074       start = ((UChar*)(oc->image)) + sectab_i->PointerToRawData;
2075       end   = start + sz - 1;
2076
2077       if (kind == SECTIONKIND_OTHER
2078           /* Ignore sections called which contain stabs debugging
2079              information. */
2080           && 0 != strcmp(".stab", sectab_i->Name)
2081           && 0 != strcmp(".stabstr", sectab_i->Name)
2082           /* ignore constructor section for now */
2083           && 0 != strcmp(".ctors", sectab_i->Name)
2084          ) {
2085          errorBelch("Unknown PEi386 section name `%s' (while processing: %s)", sectab_i->Name, oc->fileName);
2086          return 0;
2087       }
2088
2089       if (kind != SECTIONKIND_OTHER && end >= start) {
2090          addSection(oc, kind, start, end);
2091          addProddableBlock(oc, start, end - start + 1);
2092       }
2093    }
2094
2095    /* Copy exported symbols into the ObjectCode. */
2096
2097    oc->n_symbols = hdr->NumberOfSymbols;
2098    oc->symbols   = stgMallocBytes(oc->n_symbols * sizeof(char*),
2099                                   "ocGetNames_PEi386(oc->symbols)");
2100    /* Call me paranoid; I don't care. */
2101    for (i = 0; i < oc->n_symbols; i++)
2102       oc->symbols[i] = NULL;
2103
2104    i = 0;
2105    while (1) {
2106       COFF_symbol* symtab_i;
2107       if (i >= (Int32)(hdr->NumberOfSymbols)) break;
2108       symtab_i = (COFF_symbol*)
2109                  myindex ( sizeof_COFF_symbol, symtab, i );
2110
2111       addr  = NULL;
2112
2113       if (symtab_i->StorageClass == MYIMAGE_SYM_CLASS_EXTERNAL
2114           && symtab_i->SectionNumber != MYIMAGE_SYM_UNDEFINED) {
2115          /* This symbol is global and defined, viz, exported */
2116          /* for MYIMAGE_SYMCLASS_EXTERNAL
2117                 && !MYIMAGE_SYM_UNDEFINED,
2118             the address of the symbol is:
2119                 address of relevant section + offset in section
2120          */
2121          COFF_section* sectabent
2122             = (COFF_section*) myindex ( sizeof_COFF_section,
2123                                         sectab,
2124                                         symtab_i->SectionNumber-1 );
2125          addr = ((UChar*)(oc->image))
2126                 + (sectabent->PointerToRawData
2127                    + symtab_i->Value);
2128       }
2129       else
2130       if (symtab_i->SectionNumber == MYIMAGE_SYM_UNDEFINED
2131           && symtab_i->Value > 0) {
2132          /* This symbol isn't in any section at all, ie, global bss.
2133             Allocate zeroed space for it. */
2134          addr = stgCallocBytes(1, symtab_i->Value,
2135                                "ocGetNames_PEi386(non-anonymous bss)");
2136          addSection(oc, SECTIONKIND_RWDATA, addr,
2137                         ((UChar*)addr) + symtab_i->Value - 1);
2138          addProddableBlock(oc, addr, symtab_i->Value);
2139          /* debugBelch("BSS      section at 0x%x\n", addr); */
2140       }
2141
2142       if (addr != NULL ) {
2143          sname = cstring_from_COFF_symbol_name ( symtab_i->Name, strtab );
2144          /* debugBelch("addSymbol %p `%s \n", addr,sname);  */
2145          IF_DEBUG(linker, debugBelch("addSymbol %p `%s'\n", addr,sname);)
2146          ASSERT(i >= 0 && i < oc->n_symbols);
2147          /* cstring_from_COFF_symbol_name always succeeds. */
2148          oc->symbols[i] = sname;
2149          ghciInsertStrHashTable(oc->fileName, symhash, sname, addr);
2150       } else {
2151 #        if 0
2152          debugBelch(
2153                    "IGNORING symbol %d\n"
2154                    "     name `",
2155                    i
2156                  );
2157          printName ( symtab_i->Name, strtab );
2158          debugBelch(
2159                    "'\n"
2160                    "    value 0x%x\n"
2161                    "   1+sec# %d\n"
2162                    "     type 0x%x\n"
2163                    "   sclass 0x%x\n"
2164                    "     nAux %d\n",
2165                    symtab_i->Value,
2166                    (Int32)(symtab_i->SectionNumber),
2167                    (UInt32)symtab_i->Type,
2168                    (UInt32)symtab_i->StorageClass,
2169                    (UInt32)symtab_i->NumberOfAuxSymbols
2170                  );
2171 #        endif
2172       }
2173
2174       i += symtab_i->NumberOfAuxSymbols;
2175       i++;
2176    }
2177
2178    return 1;
2179 }
2180
2181
2182 static int
2183 ocResolve_PEi386 ( ObjectCode* oc )
2184 {
2185    COFF_header*  hdr;
2186    COFF_section* sectab;
2187    COFF_symbol*  symtab;
2188    UChar*        strtab;
2189
2190    UInt32        A;
2191    UInt32        S;
2192    UInt32*       pP;
2193
2194    int i;
2195    UInt32 j, noRelocs;
2196
2197    /* ToDo: should be variable-sized?  But is at least safe in the
2198       sense of buffer-overrun-proof. */
2199    char symbol[1000];
2200    /* debugBelch("resolving for %s\n", oc->fileName); */
2201
2202    hdr = (COFF_header*)(oc->image);
2203    sectab = (COFF_section*) (
2204                ((UChar*)(oc->image))
2205                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2206             );
2207    symtab = (COFF_symbol*) (
2208                ((UChar*)(oc->image))
2209                + hdr->PointerToSymbolTable
2210             );
2211    strtab = ((UChar*)(oc->image))
2212             + hdr->PointerToSymbolTable
2213             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2214
2215    for (i = 0; i < hdr->NumberOfSections; i++) {
2216       COFF_section* sectab_i
2217          = (COFF_section*)
2218            myindex ( sizeof_COFF_section, sectab, i );
2219       COFF_reloc* reltab
2220          = (COFF_reloc*) (
2221               ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
2222            );
2223
2224       /* Ignore sections called which contain stabs debugging
2225          information. */
2226       if (0 == strcmp(".stab", sectab_i->Name)
2227           || 0 == strcmp(".stabstr", sectab_i->Name)
2228           || 0 == strcmp(".ctors", sectab_i->Name))
2229          continue;
2230
2231       if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
2232         /* If the relocation field (a short) has overflowed, the
2233          * real count can be found in the first reloc entry.
2234          *
2235          * See Section 4.1 (last para) of the PE spec (rev6.0).
2236          *
2237          * Nov2003 update: the GNU linker still doesn't correctly
2238          * handle the generation of relocatable object files with
2239          * overflown relocations. Hence the output to warn of potential
2240          * troubles.
2241          */
2242         COFF_reloc* rel = (COFF_reloc*)
2243                            myindex ( sizeof_COFF_reloc, reltab, 0 );
2244         noRelocs = rel->VirtualAddress;
2245         debugBelch("WARNING: Overflown relocation field (# relocs found: %u)\n",
2246                    noRelocs);
2247         j = 1;
2248       } else {
2249         noRelocs = sectab_i->NumberOfRelocations;
2250         j = 0;
2251       }
2252
2253
2254       for (; j < noRelocs; j++) {
2255          COFF_symbol* sym;
2256          COFF_reloc* reltab_j
2257             = (COFF_reloc*)
2258               myindex ( sizeof_COFF_reloc, reltab, j );
2259
2260          /* the location to patch */
2261          pP = (UInt32*)(
2262                  ((UChar*)(oc->image))
2263                  + (sectab_i->PointerToRawData
2264                     + reltab_j->VirtualAddress
2265                     - sectab_i->VirtualAddress )
2266               );
2267          /* the existing contents of pP */
2268          A = *pP;
2269          /* the symbol to connect to */
2270          sym = (COFF_symbol*)
2271                myindex ( sizeof_COFF_symbol,
2272                          symtab, reltab_j->SymbolTableIndex );
2273          IF_DEBUG(linker,
2274                   debugBelch(
2275                             "reloc sec %2d num %3d:  type 0x%-4x   "
2276                             "vaddr 0x%-8x   name `",
2277                             i, j,
2278                             (UInt32)reltab_j->Type,
2279                             reltab_j->VirtualAddress );
2280                             printName ( sym->Name, strtab );
2281                             debugBelch("'\n" ));
2282
2283          if (sym->StorageClass == MYIMAGE_SYM_CLASS_STATIC) {
2284             COFF_section* section_sym
2285                = findPEi386SectionCalled ( oc, sym->Name );
2286             if (!section_sym) {
2287                errorBelch("%s: can't find section `%s'", oc->fileName, sym->Name);
2288                return 0;
2289             }
2290             S = ((UInt32)(oc->image))
2291                 + (section_sym->PointerToRawData
2292                    + sym->Value);
2293          } else {
2294             copyName ( sym->Name, strtab, symbol, 1000-1 );
2295             (void*)S = lookupLocalSymbol( oc, symbol );
2296             if ((void*)S != NULL) goto foundit;
2297             (void*)S = lookupSymbol( symbol );
2298             if ((void*)S != NULL) goto foundit;
2299             zapTrailingAtSign ( symbol );
2300             (void*)S = lookupLocalSymbol( oc, symbol );
2301             if ((void*)S != NULL) goto foundit;
2302             (void*)S = lookupSymbol( symbol );
2303             if ((void*)S != NULL) goto foundit;
2304             /* Newline first because the interactive linker has printed "linking..." */
2305             errorBelch("\n%s: unknown symbol `%s'", oc->fileName, symbol);
2306             return 0;
2307            foundit:;
2308          }
2309          checkProddableBlock(oc, pP);
2310          switch (reltab_j->Type) {
2311             case MYIMAGE_REL_I386_DIR32:
2312                *pP = A + S;
2313                break;
2314             case MYIMAGE_REL_I386_REL32:
2315                /* Tricky.  We have to insert a displacement at
2316                   pP which, when added to the PC for the _next_
2317                   insn, gives the address of the target (S).
2318                   Problem is to know the address of the next insn
2319                   when we only know pP.  We assume that this
2320                   literal field is always the last in the insn,
2321                   so that the address of the next insn is pP+4
2322                   -- hence the constant 4.
2323                   Also I don't know if A should be added, but so
2324                   far it has always been zero.
2325
2326                   SOF 05/2005: 'A' (old contents of *pP) have been observed
2327                   to contain values other than zero (the 'wx' object file
2328                   that came with wxhaskell-0.9.4; dunno how it was compiled..).
2329                   So, add displacement to old value instead of asserting
2330                   A to be zero. Fixes wxhaskell-related crashes, and no other
2331                   ill effects have been observed.
2332
2333                   Update: the reason why we're seeing these more elaborate
2334                   relocations is due to a switch in how the NCG compiles SRTs
2335                   and offsets to them from info tables. SRTs live in .(ro)data,
2336                   while info tables live in .text, causing GAS to emit REL32/DISP32
2337                   relocations with non-zero values. Adding the displacement is
2338                   the right thing to do.
2339                */
2340                *pP = S - ((UInt32)pP) - 4 + A;
2341                break;
2342             default:
2343                debugBelch("%s: unhandled PEi386 relocation type %d",
2344                      oc->fileName, reltab_j->Type);
2345                return 0;
2346          }
2347
2348       }
2349    }
2350
2351    IF_DEBUG(linker, debugBelch("completed %s", oc->fileName));
2352    return 1;
2353 }
2354
2355 #endif /* defined(OBJFORMAT_PEi386) */
2356
2357
2358 /* --------------------------------------------------------------------------
2359  * ELF specifics
2360  * ------------------------------------------------------------------------*/
2361
2362 #if defined(OBJFORMAT_ELF)
2363
2364 #define FALSE 0
2365 #define TRUE  1
2366
2367 #if defined(sparc_HOST_ARCH)
2368 #  define ELF_TARGET_SPARC  /* Used inside <elf.h> */
2369 #elif defined(i386_HOST_ARCH)
2370 #  define ELF_TARGET_386    /* Used inside <elf.h> */
2371 #elif defined(x86_64_HOST_ARCH)
2372 #  define ELF_TARGET_X64_64
2373 #  define ELF_64BIT
2374 #elif defined (ia64_HOST_ARCH)
2375 #  define ELF_TARGET_IA64   /* Used inside <elf.h> */
2376 #  define ELF_64BIT
2377 #  define ELF_FUNCTION_DESC /* calling convention uses function descriptors */
2378 #  define ELF_NEED_GOT      /* needs Global Offset Table */
2379 #  define ELF_NEED_PLT      /* needs Procedure Linkage Tables */
2380 #endif
2381
2382 #if !defined(openbsd_HOST_OS)
2383 #include <elf.h>
2384 #else
2385 /* openbsd elf has things in different places, with diff names */
2386 #include <elf_abi.h>
2387 #include <machine/reloc.h>
2388 #define R_386_32    RELOC_32
2389 #define R_386_PC32  RELOC_PC32
2390 #endif
2391
2392 /*
2393  * Define a set of types which can be used for both ELF32 and ELF64
2394  */
2395
2396 #ifdef ELF_64BIT
2397 #define ELFCLASS    ELFCLASS64
2398 #define Elf_Addr    Elf64_Addr
2399 #define Elf_Word    Elf64_Word
2400 #define Elf_Sword   Elf64_Sword
2401 #define Elf_Ehdr    Elf64_Ehdr
2402 #define Elf_Phdr    Elf64_Phdr
2403 #define Elf_Shdr    Elf64_Shdr
2404 #define Elf_Sym     Elf64_Sym
2405 #define Elf_Rel     Elf64_Rel
2406 #define Elf_Rela    Elf64_Rela
2407 #define ELF_ST_TYPE ELF64_ST_TYPE
2408 #define ELF_ST_BIND ELF64_ST_BIND
2409 #define ELF_R_TYPE  ELF64_R_TYPE
2410 #define ELF_R_SYM   ELF64_R_SYM
2411 #else
2412 #define ELFCLASS    ELFCLASS32
2413 #define Elf_Addr    Elf32_Addr
2414 #define Elf_Word    Elf32_Word
2415 #define Elf_Sword   Elf32_Sword
2416 #define Elf_Ehdr    Elf32_Ehdr
2417 #define Elf_Phdr    Elf32_Phdr
2418 #define Elf_Shdr    Elf32_Shdr
2419 #define Elf_Sym     Elf32_Sym
2420 #define Elf_Rel     Elf32_Rel
2421 #define Elf_Rela    Elf32_Rela
2422 #ifndef ELF_ST_TYPE
2423 #define ELF_ST_TYPE ELF32_ST_TYPE
2424 #endif
2425 #ifndef ELF_ST_BIND
2426 #define ELF_ST_BIND ELF32_ST_BIND
2427 #endif
2428 #ifndef ELF_R_TYPE
2429 #define ELF_R_TYPE  ELF32_R_TYPE
2430 #endif
2431 #ifndef ELF_R_SYM
2432 #define ELF_R_SYM   ELF32_R_SYM
2433 #endif
2434 #endif
2435
2436
2437 /*
2438  * Functions to allocate entries in dynamic sections.  Currently we simply
2439  * preallocate a large number, and we don't check if a entry for the given
2440  * target already exists (a linear search is too slow).  Ideally these
2441  * entries would be associated with symbols.
2442  */
2443
2444 /* These sizes sufficient to load HSbase + HShaskell98 + a few modules */
2445 #define GOT_SIZE            0x20000
2446 #define FUNCTION_TABLE_SIZE 0x10000
2447 #define PLT_SIZE            0x08000
2448
2449 #ifdef ELF_NEED_GOT
2450 static Elf_Addr got[GOT_SIZE];
2451 static unsigned int gotIndex;
2452 static Elf_Addr gp_val = (Elf_Addr)got;
2453
2454 static Elf_Addr
2455 allocateGOTEntry(Elf_Addr target)
2456 {
2457    Elf_Addr *entry;
2458
2459    if (gotIndex >= GOT_SIZE)
2460       barf("Global offset table overflow");
2461
2462    entry = &got[gotIndex++];
2463    *entry = target;
2464    return (Elf_Addr)entry;
2465 }
2466 #endif
2467
2468 #ifdef ELF_FUNCTION_DESC
2469 typedef struct {
2470    Elf_Addr ip;
2471    Elf_Addr gp;
2472 } FunctionDesc;
2473
2474 static FunctionDesc functionTable[FUNCTION_TABLE_SIZE];
2475 static unsigned int functionTableIndex;
2476
2477 static Elf_Addr
2478 allocateFunctionDesc(Elf_Addr target)
2479 {
2480    FunctionDesc *entry;
2481
2482    if (functionTableIndex >= FUNCTION_TABLE_SIZE)
2483       barf("Function table overflow");
2484
2485    entry = &functionTable[functionTableIndex++];
2486    entry->ip = target;
2487    entry->gp = (Elf_Addr)gp_val;
2488    return (Elf_Addr)entry;
2489 }
2490
2491 static Elf_Addr
2492 copyFunctionDesc(Elf_Addr target)
2493 {
2494    FunctionDesc *olddesc = (FunctionDesc *)target;
2495    FunctionDesc *newdesc;
2496
2497    newdesc = (FunctionDesc *)allocateFunctionDesc(olddesc->ip);
2498    newdesc->gp = olddesc->gp;
2499    return (Elf_Addr)newdesc;
2500 }
2501 #endif
2502
2503 #ifdef ELF_NEED_PLT
2504 #ifdef ia64_HOST_ARCH
2505 static void ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value);
2506 static void ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc);
2507
2508 static unsigned char plt_code[] =
2509 {
2510    /* taken from binutils bfd/elfxx-ia64.c */
2511    0x0b, 0x78, 0x00, 0x02, 0x00, 0x24,  /*   [MMI]       addl r15=0,r1;;    */
2512    0x00, 0x41, 0x3c, 0x30, 0x28, 0xc0,  /*               ld8 r16=[r15],8    */
2513    0x01, 0x08, 0x00, 0x84,              /*               mov r14=r1;;       */
2514    0x11, 0x08, 0x00, 0x1e, 0x18, 0x10,  /*   [MIB]       ld8 r1=[r15]       */
2515    0x60, 0x80, 0x04, 0x80, 0x03, 0x00,  /*               mov b6=r16         */
2516    0x60, 0x00, 0x80, 0x00               /*               br.few b6;;        */
2517 };
2518
2519 /* If we can't get to the function descriptor via gp, take a local copy of it */
2520 #define PLT_RELOC(code, target) { \
2521    Elf64_Sxword rel_value = target - gp_val; \
2522    if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff)) \
2523       ia64_reloc_gprel22((Elf_Addr)code, copyFunctionDesc(target)); \
2524    else \
2525       ia64_reloc_gprel22((Elf_Addr)code, target); \
2526    }
2527 #endif
2528
2529 typedef struct {
2530    unsigned char code[sizeof(plt_code)];
2531 } PLTEntry;
2532
2533 static Elf_Addr
2534 allocatePLTEntry(Elf_Addr target, ObjectCode *oc)
2535 {
2536    PLTEntry *plt = (PLTEntry *)oc->plt;
2537    PLTEntry *entry;
2538
2539    if (oc->pltIndex >= PLT_SIZE)
2540       barf("Procedure table overflow");
2541
2542    entry = &plt[oc->pltIndex++];
2543    memcpy(entry->code, plt_code, sizeof(entry->code));
2544    PLT_RELOC(entry->code, target);
2545    return (Elf_Addr)entry;
2546 }
2547
2548 static unsigned int
2549 PLTSize(void)
2550 {
2551    return (PLT_SIZE * sizeof(PLTEntry));
2552 }
2553 #endif
2554
2555
2556 #if x86_64_HOST_ARCH
2557 // On x86_64, 32-bit relocations are often used, which requires that
2558 // we can resolve a symbol to a 32-bit offset.  However, shared
2559 // libraries are placed outside the 2Gb area, which leaves us with a
2560 // problem when we need to give a 32-bit offset to a symbol in a
2561 // shared library.
2562 //
2563 // For a function symbol, we can allocate a bounce sequence inside the
2564 // 2Gb area and resolve the symbol to this.  The bounce sequence is
2565 // simply a long jump instruction to the real location of the symbol.
2566 //
2567 // For data references, we're screwed.
2568 //
2569 typedef struct {
2570     unsigned char jmp[8];  /* 6 byte instruction: jmpq *0x00000002(%rip) */
2571     void *addr;
2572 } x86_64_bounce;
2573
2574 #define X86_64_BB_SIZE 1024
2575
2576 static x86_64_bounce *x86_64_bounce_buffer = NULL;
2577 static nat x86_64_bb_next_off;
2578
2579 static void*
2580 x86_64_high_symbol( char *lbl, void *addr )
2581 {
2582     x86_64_bounce *bounce;
2583
2584     if ( x86_64_bounce_buffer == NULL ||
2585          x86_64_bb_next_off >= X86_64_BB_SIZE ) {
2586         x86_64_bounce_buffer =
2587             mmap(NULL, X86_64_BB_SIZE * sizeof(x86_64_bounce),
2588                  PROT_EXEC|PROT_READ|PROT_WRITE,
2589                  MAP_PRIVATE|MAP_32BIT|MAP_ANONYMOUS, -1, 0);
2590         if (x86_64_bounce_buffer == MAP_FAILED) {
2591             barf("x86_64_high_symbol: mmap failed");
2592         }
2593         x86_64_bb_next_off = 0;
2594     }
2595     bounce = &x86_64_bounce_buffer[x86_64_bb_next_off];
2596     bounce->jmp[0] = 0xff;
2597     bounce->jmp[1] = 0x25;
2598     bounce->jmp[2] = 0x02;
2599     bounce->jmp[3] = 0x00;
2600     bounce->jmp[4] = 0x00;
2601     bounce->jmp[5] = 0x00;
2602     bounce->addr = addr;
2603     x86_64_bb_next_off++;
2604
2605     IF_DEBUG(linker, debugBelch("x86_64: allocated bounce entry for %s->%p at %p\n",
2606                                 lbl, addr, bounce));
2607
2608     insertStrHashTable(symhash, lbl, bounce);
2609     return bounce;
2610 }
2611 #endif
2612
2613
2614 /*
2615  * Generic ELF functions
2616  */
2617
2618 static char *
2619 findElfSection ( void* objImage, Elf_Word sh_type )
2620 {
2621    char* ehdrC = (char*)objImage;
2622    Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2623    Elf_Shdr* shdr = (Elf_Shdr*)(ehdrC + ehdr->e_shoff);
2624    char* sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
2625    char* ptr = NULL;
2626    int i;
2627
2628    for (i = 0; i < ehdr->e_shnum; i++) {
2629       if (shdr[i].sh_type == sh_type
2630           /* Ignore the section header's string table. */
2631           && i != ehdr->e_shstrndx
2632           /* Ignore string tables named .stabstr, as they contain
2633              debugging info. */
2634           && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
2635          ) {
2636          ptr = ehdrC + shdr[i].sh_offset;
2637          break;
2638       }
2639    }
2640    return ptr;
2641 }
2642
2643 #if defined(ia64_HOST_ARCH)
2644 static Elf_Addr
2645 findElfSegment ( void* objImage, Elf_Addr vaddr )
2646 {
2647    char* ehdrC = (char*)objImage;
2648    Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2649    Elf_Phdr* phdr = (Elf_Phdr*)(ehdrC + ehdr->e_phoff);
2650    Elf_Addr segaddr = 0;
2651    int i;
2652
2653    for (i = 0; i < ehdr->e_phnum; i++) {
2654       segaddr = phdr[i].p_vaddr;
2655       if ((vaddr >= segaddr) && (vaddr < segaddr + phdr[i].p_memsz))
2656               break;
2657    }
2658    return segaddr;
2659 }
2660 #endif
2661
2662 static int
2663 ocVerifyImage_ELF ( ObjectCode* oc )
2664 {
2665    Elf_Shdr* shdr;
2666    Elf_Sym*  stab;
2667    int i, j, nent, nstrtab, nsymtabs;
2668    char* sh_strtab;
2669    char* strtab;
2670
2671    char*     ehdrC = (char*)(oc->image);
2672    Elf_Ehdr* ehdr  = (Elf_Ehdr*)ehdrC;
2673
2674    if (ehdr->e_ident[EI_MAG0] != ELFMAG0 ||
2675        ehdr->e_ident[EI_MAG1] != ELFMAG1 ||
2676        ehdr->e_ident[EI_MAG2] != ELFMAG2 ||
2677        ehdr->e_ident[EI_MAG3] != ELFMAG3) {
2678       errorBelch("%s: not an ELF object", oc->fileName);
2679       return 0;
2680    }
2681
2682    if (ehdr->e_ident[EI_CLASS] != ELFCLASS) {
2683       errorBelch("%s: unsupported ELF format", oc->fileName);
2684       return 0;
2685    }
2686
2687    if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) {
2688        IF_DEBUG(linker,debugBelch( "Is little-endian\n" ));
2689    } else
2690    if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) {
2691        IF_DEBUG(linker,debugBelch( "Is big-endian\n" ));
2692    } else {
2693        errorBelch("%s: unknown endiannness", oc->fileName);
2694        return 0;
2695    }
2696
2697    if (ehdr->e_type != ET_REL) {
2698       errorBelch("%s: not a relocatable object (.o) file", oc->fileName);
2699       return 0;
2700    }
2701    IF_DEBUG(linker, debugBelch( "Is a relocatable object (.o) file\n" ));
2702
2703    IF_DEBUG(linker,debugBelch( "Architecture is " ));
2704    switch (ehdr->e_machine) {
2705       case EM_386:   IF_DEBUG(linker,debugBelch( "x86" )); break;
2706       case EM_SPARC: IF_DEBUG(linker,debugBelch( "sparc" )); break;
2707 #ifdef EM_IA_64
2708       case EM_IA_64: IF_DEBUG(linker,debugBelch( "ia64" )); break;
2709 #endif
2710       case EM_PPC:   IF_DEBUG(linker,debugBelch( "powerpc32" )); break;
2711 #ifdef EM_X86_64
2712       case EM_X86_64: IF_DEBUG(linker,debugBelch( "x86_64" )); break;
2713 #endif
2714       default:       IF_DEBUG(linker,debugBelch( "unknown" ));
2715                      errorBelch("%s: unknown architecture", oc->fileName);
2716                      return 0;
2717    }
2718
2719    IF_DEBUG(linker,debugBelch(
2720              "\nSection header table: start %d, n_entries %d, ent_size %d\n",
2721              ehdr->e_shoff, ehdr->e_shnum, ehdr->e_shentsize  ));
2722
2723    ASSERT (ehdr->e_shentsize == sizeof(Elf_Shdr));
2724
2725    shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
2726
2727    if (ehdr->e_shstrndx == SHN_UNDEF) {
2728       errorBelch("%s: no section header string table", oc->fileName);
2729       return 0;
2730    } else {
2731       IF_DEBUG(linker,debugBelch( "Section header string table is section %d\n",
2732                           ehdr->e_shstrndx));
2733       sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
2734    }
2735
2736    for (i = 0; i < ehdr->e_shnum; i++) {
2737       IF_DEBUG(linker,debugBelch("%2d:  ", i ));
2738       IF_DEBUG(linker,debugBelch("type=%2d  ", (int)shdr[i].sh_type ));
2739       IF_DEBUG(linker,debugBelch("size=%4d  ", (int)shdr[i].sh_size ));
2740       IF_DEBUG(linker,debugBelch("offs=%4d  ", (int)shdr[i].sh_offset ));
2741       IF_DEBUG(linker,debugBelch("  (%p .. %p)  ",
2742                ehdrC + shdr[i].sh_offset,
2743                       ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1));
2744
2745       if (shdr[i].sh_type == SHT_REL) {
2746           IF_DEBUG(linker,debugBelch("Rel  " ));
2747       } else if (shdr[i].sh_type == SHT_RELA) {
2748           IF_DEBUG(linker,debugBelch("RelA " ));
2749       } else {
2750           IF_DEBUG(linker,debugBelch("     "));
2751       }
2752       if (sh_strtab) {
2753           IF_DEBUG(linker,debugBelch("sname=%s\n", sh_strtab + shdr[i].sh_name ));
2754       }
2755    }
2756
2757    IF_DEBUG(linker,debugBelch( "\nString tables" ));
2758    strtab = NULL;
2759    nstrtab = 0;
2760    for (i = 0; i < ehdr->e_shnum; i++) {
2761       if (shdr[i].sh_type == SHT_STRTAB
2762           /* Ignore the section header's string table. */
2763           && i != ehdr->e_shstrndx
2764           /* Ignore string tables named .stabstr, as they contain
2765              debugging info. */
2766           && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
2767          ) {
2768          IF_DEBUG(linker,debugBelch("   section %d is a normal string table", i ));
2769          strtab = ehdrC + shdr[i].sh_offset;
2770          nstrtab++;
2771       }
2772    }
2773    if (nstrtab != 1) {
2774       errorBelch("%s: no string tables, or too many", oc->fileName);
2775       return 0;
2776    }
2777
2778    nsymtabs = 0;
2779    IF_DEBUG(linker,debugBelch( "\nSymbol tables" ));
2780    for (i = 0; i < ehdr->e_shnum; i++) {
2781       if (shdr[i].sh_type != SHT_SYMTAB) continue;
2782       IF_DEBUG(linker,debugBelch( "section %d is a symbol table\n", i ));
2783       nsymtabs++;
2784       stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
2785       nent = shdr[i].sh_size / sizeof(Elf_Sym);
2786       IF_DEBUG(linker,debugBelch( "   number of entries is apparently %d (%d rem)\n",
2787                nent,
2788                shdr[i].sh_size % sizeof(Elf_Sym)
2789              ));
2790       if (0 != shdr[i].sh_size % sizeof(Elf_Sym)) {
2791          errorBelch("%s: non-integral number of symbol table entries", oc->fileName);
2792          return 0;
2793       }
2794       for (j = 0; j < nent; j++) {
2795          IF_DEBUG(linker,debugBelch("   %2d  ", j ));
2796          IF_DEBUG(linker,debugBelch("  sec=%-5d  size=%-3d  val=%5p  ",
2797                              (int)stab[j].st_shndx,
2798                              (int)stab[j].st_size,
2799                              (char*)stab[j].st_value ));
2800
2801          IF_DEBUG(linker,debugBelch("type=" ));
2802          switch (ELF_ST_TYPE(stab[j].st_info)) {
2803             case STT_NOTYPE:  IF_DEBUG(linker,debugBelch("notype " )); break;
2804             case STT_OBJECT:  IF_DEBUG(linker,debugBelch("object " )); break;
2805             case STT_FUNC  :  IF_DEBUG(linker,debugBelch("func   " )); break;
2806             case STT_SECTION: IF_DEBUG(linker,debugBelch("section" )); break;
2807             case STT_FILE:    IF_DEBUG(linker,debugBelch("file   " )); break;
2808             default:          IF_DEBUG(linker,debugBelch("?      " )); break;
2809          }
2810          IF_DEBUG(linker,debugBelch("  " ));
2811
2812          IF_DEBUG(linker,debugBelch("bind=" ));
2813          switch (ELF_ST_BIND(stab[j].st_info)) {
2814             case STB_LOCAL :  IF_DEBUG(linker,debugBelch("local " )); break;
2815             case STB_GLOBAL:  IF_DEBUG(linker,debugBelch("global" )); break;
2816             case STB_WEAK  :  IF_DEBUG(linker,debugBelch("weak  " )); break;
2817             default:          IF_DEBUG(linker,debugBelch("?     " )); break;
2818          }
2819          IF_DEBUG(linker,debugBelch("  " ));
2820
2821          IF_DEBUG(linker,debugBelch("name=%s\n", strtab + stab[j].st_name ));
2822       }
2823    }
2824
2825    if (nsymtabs == 0) {
2826       errorBelch("%s: didn't find any symbol tables", oc->fileName);
2827       return 0;
2828    }
2829
2830    return 1;
2831 }
2832
2833 static int getSectionKind_ELF( Elf_Shdr *hdr, int *is_bss )
2834 {
2835     *is_bss = FALSE;
2836
2837     if (hdr->sh_type == SHT_PROGBITS
2838         && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_EXECINSTR)) {
2839         /* .text-style section */
2840         return SECTIONKIND_CODE_OR_RODATA;
2841     }
2842
2843     if (hdr->sh_type == SHT_PROGBITS
2844             && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
2845             /* .data-style section */
2846             return SECTIONKIND_RWDATA;
2847     }
2848
2849     if (hdr->sh_type == SHT_PROGBITS
2850         && (hdr->sh_flags & SHF_ALLOC) && !(hdr->sh_flags & SHF_WRITE)) {
2851         /* .rodata-style section */
2852         return SECTIONKIND_CODE_OR_RODATA;
2853     }
2854
2855     if (hdr->sh_type == SHT_NOBITS
2856         && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
2857         /* .bss-style section */
2858         *is_bss = TRUE;
2859         return SECTIONKIND_RWDATA;
2860     }
2861
2862     return SECTIONKIND_OTHER;
2863 }
2864
2865
2866 static int
2867 ocGetNames_ELF ( ObjectCode* oc )
2868 {
2869    int i, j, k, nent;
2870    Elf_Sym* stab;
2871
2872    char*     ehdrC    = (char*)(oc->image);
2873    Elf_Ehdr* ehdr     = (Elf_Ehdr*)ehdrC;
2874    char*     strtab   = findElfSection ( ehdrC, SHT_STRTAB );
2875    Elf_Shdr* shdr     = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
2876
2877    ASSERT(symhash != NULL);
2878
2879    if (!strtab) {
2880       errorBelch("%s: no strtab", oc->fileName);
2881       return 0;
2882    }
2883
2884    k = 0;
2885    for (i = 0; i < ehdr->e_shnum; i++) {
2886       /* Figure out what kind of section it is.  Logic derived from
2887          Figure 1.14 ("Special Sections") of the ELF document
2888          ("Portable Formats Specification, Version 1.1"). */
2889       int         is_bss = FALSE;
2890       SectionKind kind   = getSectionKind_ELF(&shdr[i], &is_bss);
2891
2892       if (is_bss && shdr[i].sh_size > 0) {
2893          /* This is a non-empty .bss section.  Allocate zeroed space for
2894             it, and set its .sh_offset field such that
2895             ehdrC + .sh_offset == addr_of_zeroed_space.  */
2896          char* zspace = stgCallocBytes(1, shdr[i].sh_size,
2897                                        "ocGetNames_ELF(BSS)");
2898          shdr[i].sh_offset = ((char*)zspace) - ((char*)ehdrC);
2899          /*
2900          debugBelch("BSS section at 0x%x, size %d\n",
2901                          zspace, shdr[i].sh_size);
2902          */
2903       }
2904
2905       /* fill in the section info */
2906       if (kind != SECTIONKIND_OTHER && shdr[i].sh_size > 0) {
2907          addProddableBlock(oc, ehdrC + shdr[i].sh_offset, shdr[i].sh_size);
2908          addSection(oc, kind, ehdrC + shdr[i].sh_offset,
2909                         ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1);
2910       }
2911
2912       if (shdr[i].sh_type != SHT_SYMTAB) continue;
2913
2914       /* copy stuff into this module's object symbol table */
2915       stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
2916       nent = shdr[i].sh_size / sizeof(Elf_Sym);
2917
2918       oc->n_symbols = nent;
2919       oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
2920                                    "ocGetNames_ELF(oc->symbols)");
2921
2922       for (j = 0; j < nent; j++) {
2923
2924          char  isLocal = FALSE; /* avoids uninit-var warning */
2925          char* ad      = NULL;
2926          char* nm      = strtab + stab[j].st_name;
2927          int   secno   = stab[j].st_shndx;
2928
2929          /* Figure out if we want to add it; if so, set ad to its
2930             address.  Otherwise leave ad == NULL. */
2931
2932          if (secno == SHN_COMMON) {
2933             isLocal = FALSE;
2934             ad = stgCallocBytes(1, stab[j].st_size, "ocGetNames_ELF(COMMON)");
2935             /*
2936             debugBelch("COMMON symbol, size %d name %s\n",
2937                             stab[j].st_size, nm);
2938             */
2939             /* Pointless to do addProddableBlock() for this area,
2940                since the linker should never poke around in it. */
2941          }
2942          else
2943          if ( ( ELF_ST_BIND(stab[j].st_info)==STB_GLOBAL
2944                 || ELF_ST_BIND(stab[j].st_info)==STB_LOCAL
2945               )
2946               /* and not an undefined symbol */
2947               && stab[j].st_shndx != SHN_UNDEF
2948               /* and not in a "special section" */
2949               && stab[j].st_shndx < SHN_LORESERVE
2950               &&
2951               /* and it's a not a section or string table or anything silly */
2952               ( ELF_ST_TYPE(stab[j].st_info)==STT_FUNC ||
2953                 ELF_ST_TYPE(stab[j].st_info)==STT_OBJECT ||
2954                 ELF_ST_TYPE(stab[j].st_info)==STT_NOTYPE
2955               )
2956             ) {
2957             /* Section 0 is the undefined section, hence > and not >=. */
2958             ASSERT(secno > 0 && secno < ehdr->e_shnum);
2959             /*
2960             if (shdr[secno].sh_type == SHT_NOBITS) {
2961                debugBelch("   BSS symbol, size %d off %d name %s\n",
2962                                stab[j].st_size, stab[j].st_value, nm);
2963             }
2964             */
2965             ad = ehdrC + shdr[ secno ].sh_offset + stab[j].st_value;
2966             if (ELF_ST_BIND(stab[j].st_info)==STB_LOCAL) {
2967                isLocal = TRUE;
2968             } else {
2969 #ifdef ELF_FUNCTION_DESC
2970                /* dlsym() and the initialisation table both give us function
2971                 * descriptors, so to be consistent we store function descriptors
2972                 * in the symbol table */
2973                if (ELF_ST_TYPE(stab[j].st_info) == STT_FUNC)
2974                    ad = (char *)allocateFunctionDesc((Elf_Addr)ad);
2975 #endif
2976                IF_DEBUG(linker,debugBelch( "addOTabName(GLOB): %10p  %s %s",
2977                                       ad, oc->fileName, nm ));
2978                isLocal = FALSE;
2979             }
2980          }
2981
2982          /* And the decision is ... */
2983
2984          if (ad != NULL) {
2985             ASSERT(nm != NULL);
2986             oc->symbols[j] = nm;
2987             /* Acquire! */
2988             if (isLocal) {
2989                /* Ignore entirely. */
2990             } else {
2991                ghciInsertStrHashTable(oc->fileName, symhash, nm, ad);
2992             }
2993          } else {
2994             /* Skip. */
2995             IF_DEBUG(linker,debugBelch( "skipping `%s'\n",
2996                                    strtab + stab[j].st_name ));
2997             /*
2998             debugBelch(
2999                     "skipping   bind = %d,  type = %d,  shndx = %d   `%s'\n",
3000                     (int)ELF_ST_BIND(stab[j].st_info),
3001                     (int)ELF_ST_TYPE(stab[j].st_info),
3002                     (int)stab[j].st_shndx,
3003                     strtab + stab[j].st_name
3004                    );
3005             */
3006             oc->symbols[j] = NULL;
3007          }
3008
3009       }
3010    }
3011
3012    return 1;
3013 }
3014
3015 /* Do ELF relocations which lack an explicit addend.  All x86-linux
3016    relocations appear to be of this form. */
3017 static int
3018 do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
3019                          Elf_Shdr* shdr, int shnum,
3020                          Elf_Sym*  stab, char* strtab )
3021 {
3022    int j;
3023    char *symbol;
3024    Elf_Word* targ;
3025    Elf_Rel*  rtab = (Elf_Rel*) (ehdrC + shdr[shnum].sh_offset);
3026    int         nent = shdr[shnum].sh_size / sizeof(Elf_Rel);
3027    int target_shndx = shdr[shnum].sh_info;
3028    int symtab_shndx = shdr[shnum].sh_link;
3029
3030    stab  = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
3031    targ  = (Elf_Word*)(ehdrC + shdr[ target_shndx ].sh_offset);
3032    IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
3033                           target_shndx, symtab_shndx ));
3034
3035    /* Skip sections that we're not interested in. */
3036    {
3037        int is_bss;
3038        SectionKind kind = getSectionKind_ELF(&shdr[target_shndx], &is_bss);
3039        if (kind == SECTIONKIND_OTHER) {
3040            IF_DEBUG(linker,debugBelch( "skipping (target section not loaded)"));
3041            return 1;
3042        }
3043    }
3044
3045    for (j = 0; j < nent; j++) {
3046       Elf_Addr offset = rtab[j].r_offset;
3047       Elf_Addr info   = rtab[j].r_info;
3048
3049       Elf_Addr  P  = ((Elf_Addr)targ) + offset;
3050       Elf_Word* pP = (Elf_Word*)P;
3051       Elf_Addr  A  = *pP;
3052       Elf_Addr  S;
3053       void*     S_tmp;
3054       Elf_Addr  value;
3055
3056       IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p)",
3057                              j, (void*)offset, (void*)info ));
3058       if (!info) {
3059          IF_DEBUG(linker,debugBelch( " ZERO" ));
3060          S = 0;
3061       } else {
3062          Elf_Sym sym = stab[ELF_R_SYM(info)];
3063          /* First see if it is a local symbol. */
3064          if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
3065             /* Yes, so we can get the address directly from the ELF symbol
3066                table. */
3067             symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
3068             S = (Elf_Addr)
3069                 (ehdrC + shdr[ sym.st_shndx ].sh_offset
3070                        + stab[ELF_R_SYM(info)].st_value);
3071
3072          } else {
3073             /* No, so look up the name in our global table. */
3074             symbol = strtab + sym.st_name;
3075             S_tmp = lookupSymbol( symbol );
3076             S = (Elf_Addr)S_tmp;
3077          }
3078          if (!S) {
3079             errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
3080             return 0;
3081          }
3082          IF_DEBUG(linker,debugBelch( "`%s' resolves to %p\n", symbol, (void*)S ));
3083       }
3084
3085       IF_DEBUG(linker,debugBelch( "Reloc: P = %p   S = %p   A = %p\n",
3086                              (void*)P, (void*)S, (void*)A ));
3087       checkProddableBlock ( oc, pP );
3088
3089       value = S + A;
3090
3091       switch (ELF_R_TYPE(info)) {
3092 #        ifdef i386_HOST_ARCH
3093          case R_386_32:   *pP = value;     break;
3094          case R_386_PC32: *pP = value - P; break;
3095 #        endif
3096          default:
3097             errorBelch("%s: unhandled ELF relocation(Rel) type %d\n",
3098                   oc->fileName, ELF_R_TYPE(info));
3099             return 0;
3100       }
3101
3102    }
3103    return 1;
3104 }
3105
3106 /* Do ELF relocations for which explicit addends are supplied.
3107    sparc-solaris relocations appear to be of this form. */
3108 static int
3109 do_Elf_Rela_relocations ( ObjectCode* oc, char* ehdrC,
3110                           Elf_Shdr* shdr, int shnum,
3111                           Elf_Sym*  stab, char* strtab )
3112 {
3113    int j;
3114    char *symbol;
3115    Elf_Addr targ;
3116    Elf_Rela* rtab = (Elf_Rela*) (ehdrC + shdr[shnum].sh_offset);
3117    int         nent = shdr[shnum].sh_size / sizeof(Elf_Rela);
3118    int target_shndx = shdr[shnum].sh_info;
3119    int symtab_shndx = shdr[shnum].sh_link;
3120
3121    stab  = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
3122    targ  = (Elf_Addr) (ehdrC + shdr[ target_shndx ].sh_offset);
3123    IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
3124                           target_shndx, symtab_shndx ));
3125
3126    for (j = 0; j < nent; j++) {
3127 #if defined(DEBUG) || defined(sparc_HOST_ARCH) || defined(ia64_HOST_ARCH) || defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
3128       /* This #ifdef only serves to avoid unused-var warnings. */
3129       Elf_Addr  offset = rtab[j].r_offset;
3130       Elf_Addr  P      = targ + offset;
3131 #endif
3132       Elf_Addr  info   = rtab[j].r_info;
3133       Elf_Addr  A      = rtab[j].r_addend;
3134       Elf_Addr  S;
3135       void*     S_tmp;
3136       Elf_Addr  value;
3137 #     if defined(sparc_HOST_ARCH)
3138       Elf_Word* pP = (Elf_Word*)P;
3139       Elf_Word  w1, w2;
3140 #     elif defined(ia64_HOST_ARCH)
3141       Elf64_Xword *pP = (Elf64_Xword *)P;
3142       Elf_Addr addr;
3143 #     elif defined(powerpc_HOST_ARCH)
3144       Elf_Sword delta;
3145 #     endif
3146
3147       IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p %6p)   ",
3148                              j, (void*)offset, (void*)info,
3149                                 (void*)A ));
3150       if (!info) {
3151          IF_DEBUG(linker,debugBelch( " ZERO" ));
3152          S = 0;
3153       } else {
3154          Elf_Sym sym = stab[ELF_R_SYM(info)];
3155          /* First see if it is a local symbol. */
3156          if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
3157             /* Yes, so we can get the address directly from the ELF symbol
3158                table. */
3159             symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
3160             S = (Elf_Addr)
3161                 (ehdrC + shdr[ sym.st_shndx ].sh_offset
3162                        + stab[ELF_R_SYM(info)].st_value);
3163 #ifdef ELF_FUNCTION_DESC
3164             /* Make a function descriptor for this function */
3165             if (S && ELF_ST_TYPE(sym.st_info) == STT_FUNC) {
3166                S = allocateFunctionDesc(S + A);
3167                A = 0;
3168             }
3169 #endif
3170          } else {
3171             /* No, so look up the name in our global table. */
3172             symbol = strtab + sym.st_name;
3173             S_tmp = lookupSymbol( symbol );
3174             S = (Elf_Addr)S_tmp;
3175
3176 #ifdef ELF_FUNCTION_DESC
3177             /* If a function, already a function descriptor - we would
3178                have to copy it to add an offset. */
3179             if (S && (ELF_ST_TYPE(sym.st_info) == STT_FUNC) && (A != 0))
3180                errorBelch("%s: function %s with addend %p", oc->fileName, symbol, (void *)A);
3181 #endif
3182          }
3183          if (!S) {
3184            errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
3185            return 0;
3186          }
3187          IF_DEBUG(linker,debugBelch( "`%s' resolves to %p", symbol, (void*)S ));
3188       }
3189
3190       IF_DEBUG(linker,debugBelch("Reloc: P = %p   S = %p   A = %p\n",
3191                                         (void*)P, (void*)S, (void*)A ));
3192       /* checkProddableBlock ( oc, (void*)P ); */
3193
3194       value = S + A;
3195
3196       switch (ELF_R_TYPE(info)) {
3197 #        if defined(sparc_HOST_ARCH)
3198          case R_SPARC_WDISP30:
3199             w1 = *pP & 0xC0000000;
3200             w2 = (Elf_Word)((value - P) >> 2);
3201             ASSERT((w2 & 0xC0000000) == 0);
3202             w1 |= w2;
3203             *pP = w1;
3204             break;
3205          case R_SPARC_HI22:
3206             w1 = *pP & 0xFFC00000;
3207             w2 = (Elf_Word)(value >> 10);
3208             ASSERT((w2 & 0xFFC00000) == 0);
3209             w1 |= w2;
3210             *pP = w1;
3211             break;
3212          case R_SPARC_LO10:
3213             w1 = *pP & ~0x3FF;
3214             w2 = (Elf_Word)(value & 0x3FF);
3215             ASSERT((w2 & ~0x3FF) == 0);
3216             w1 |= w2;
3217             *pP = w1;
3218             break;
3219          /* According to the Sun documentation:
3220             R_SPARC_UA32
3221             This relocation type resembles R_SPARC_32, except it refers to an
3222             unaligned word. That is, the word to be relocated must be treated
3223             as four separate bytes with arbitrary alignment, not as a word
3224             aligned according to the architecture requirements.
3225
3226             (JRS: which means that freeloading on the R_SPARC_32 case
3227             is probably wrong, but hey ...)
3228          */
3229          case R_SPARC_UA32:
3230          case R_SPARC_32:
3231             w2 = (Elf_Word)value;
3232             *pP = w2;
3233             break;
3234 #        elif defined(ia64_HOST_ARCH)
3235          case R_IA64_DIR64LSB:
3236          case R_IA64_FPTR64LSB:
3237             *pP = value;
3238             break;
3239          case R_IA64_PCREL64LSB:
3240             *pP = value - P;
3241             break;
3242          case R_IA64_SEGREL64LSB:
3243             addr = findElfSegment(ehdrC, value);
3244             *pP = value - addr;
3245             break;
3246          case R_IA64_GPREL22:
3247             ia64_reloc_gprel22(P, value);
3248             break;
3249          case R_IA64_LTOFF22:
3250          case R_IA64_LTOFF22X:
3251          case R_IA64_LTOFF_FPTR22:
3252             addr = allocateGOTEntry(value);
3253             ia64_reloc_gprel22(P, addr);
3254             break;
3255          case R_IA64_PCREL21B:
3256             ia64_reloc_pcrel21(P, S, oc);
3257             break;
3258          case R_IA64_LDXMOV:
3259             /* This goes with R_IA64_LTOFF22X and points to the load to
3260              * convert into a move.  We don't implement relaxation. */
3261             break;
3262 #        elif defined(powerpc_HOST_ARCH)
3263          case R_PPC_ADDR16_LO:
3264             *(Elf32_Half*) P = value;
3265             break;
3266
3267          case R_PPC_ADDR16_HI:
3268             *(Elf32_Half*) P = value >> 16;
3269             break;
3270
3271          case R_PPC_ADDR16_HA:
3272             *(Elf32_Half*) P = (value + 0x8000) >> 16;
3273             break;
3274
3275          case R_PPC_ADDR32:
3276             *(Elf32_Word *) P = value;
3277             break;
3278
3279          case R_PPC_REL32:
3280             *(Elf32_Word *) P = value - P;
3281             break;
3282
3283          case R_PPC_REL24:
3284             delta = value - P;
3285
3286             if( delta << 6 >> 6 != delta )
3287             {
3288                value = makeJumpIsland( oc, ELF_R_SYM(info), value );
3289                delta = value - P;
3290
3291                if( value == 0 || delta << 6 >> 6 != delta )
3292                {
3293                   barf( "Unable to make ppcJumpIsland for #%d",
3294                         ELF_R_SYM(info) );
3295                   return 0;
3296                }
3297             }
3298
3299             *(Elf_Word *) P = (*(Elf_Word *) P & 0xfc000003)
3300                                           | (delta & 0x3fffffc);
3301             break;
3302 #        endif
3303
3304 #if x86_64_HOST_ARCH
3305       case R_X86_64_64:
3306           *(Elf64_Xword *)P = value;
3307           break;
3308
3309       case R_X86_64_PC32:
3310       {
3311           StgInt64 off = value - P;
3312           if (off >= 0x7fffffffL || off < -0x80000000L) {
3313               barf("R_X86_64_PC32 relocation out of range: %s = %p",
3314                    symbol, off);
3315           }
3316           *(Elf64_Word *)P = (Elf64_Word)off;
3317           break;
3318       }
3319
3320       case R_X86_64_32:
3321           if (value >= 0x7fffffffL) {
3322               barf("R_X86_64_32 relocation out of range: %s = %p\n",
3323                    symbol, value);
3324           }
3325           *(Elf64_Word *)P = (Elf64_Word)value;
3326           break;
3327
3328       case R_X86_64_32S:
3329           if ((StgInt64)value > 0x7fffffffL || (StgInt64)value < -0x80000000L) {
3330               barf("R_X86_64_32S relocation out of range: %s = %p\n",
3331                    symbol, value);
3332           }
3333           *(Elf64_Sword *)P = (Elf64_Sword)value;
3334           break;
3335 #endif
3336
3337          default:
3338             errorBelch("%s: unhandled ELF relocation(RelA) type %d\n",
3339                   oc->fileName, ELF_R_TYPE(info));
3340             return 0;
3341       }
3342
3343    }
3344    return 1;
3345 }
3346
3347 static int
3348 ocResolve_ELF ( ObjectCode* oc )
3349 {
3350    char *strtab;
3351    int   shnum, ok;
3352    Elf_Sym*  stab  = NULL;
3353    char*     ehdrC = (char*)(oc->image);
3354    Elf_Ehdr* ehdr  = (Elf_Ehdr*) ehdrC;
3355    Elf_Shdr* shdr  = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
3356
3357    /* first find "the" symbol table */
3358    stab = (Elf_Sym*) findElfSection ( ehdrC, SHT_SYMTAB );
3359
3360    /* also go find the string table */
3361    strtab = findElfSection ( ehdrC, SHT_STRTAB );
3362
3363    if (stab == NULL || strtab == NULL) {
3364       errorBelch("%s: can't find string or symbol table", oc->fileName);
3365       return 0;
3366    }
3367
3368    /* Process the relocation sections. */
3369    for (shnum = 0; shnum < ehdr->e_shnum; shnum++) {
3370       if (shdr[shnum].sh_type == SHT_REL) {
3371          ok = do_Elf_Rel_relocations ( oc, ehdrC, shdr,
3372                                        shnum, stab, strtab );
3373          if (!ok) return ok;
3374       }
3375       else
3376       if (shdr[shnum].sh_type == SHT_RELA) {
3377          ok = do_Elf_Rela_relocations ( oc, ehdrC, shdr,
3378                                         shnum, stab, strtab );
3379          if (!ok) return ok;
3380       }
3381    }
3382
3383    /* Free the local symbol table; we won't need it again. */
3384    freeHashTable(oc->lochash, NULL);
3385    oc->lochash = NULL;
3386
3387 #if defined(powerpc_HOST_ARCH)
3388    ocFlushInstructionCache( oc );
3389 #endif
3390
3391    return 1;
3392 }
3393
3394 /*
3395  * IA64 specifics
3396  * Instructions are 41 bits long, packed into 128 bit bundles with a 5-bit template
3397  * at the front.  The following utility functions pack and unpack instructions, and
3398  * take care of the most common relocations.
3399  */
3400
3401 #ifdef ia64_HOST_ARCH
3402
3403 static Elf64_Xword
3404 ia64_extract_instruction(Elf64_Xword *target)
3405 {
3406    Elf64_Xword w1, w2;
3407    int slot = (Elf_Addr)target & 3;
3408    target = (Elf_Addr)target & ~3;
3409
3410    w1 = *target;
3411    w2 = *(target+1);
3412
3413    switch (slot)
3414    {
3415       case 0:
3416          return ((w1 >> 5) & 0x1ffffffffff);
3417       case 1:
3418          return (w1 >> 46) | ((w2 & 0x7fffff) << 18);
3419       case 2:
3420          return (w2 >> 23);
3421       default:
3422          barf("ia64_extract_instruction: invalid slot %p", target);
3423    }
3424 }
3425
3426 static void
3427 ia64_deposit_instruction(Elf64_Xword *target, Elf64_Xword value)
3428 {
3429    int slot = (Elf_Addr)target & 3;
3430    target = (Elf_Addr)target & ~3;
3431
3432    switch (slot)
3433    {
3434       case 0:
3435          *target |= value << 5;
3436          break;
3437       case 1:
3438          *target |= value << 46;
3439          *(target+1) |= value >> 18;
3440          break;
3441       case 2:
3442          *(target+1) |= value << 23;
3443          break;
3444    }
3445 }
3446
3447 static void
3448 ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value)
3449 {
3450    Elf64_Xword instruction;
3451    Elf64_Sxword rel_value;
3452
3453    rel_value = value - gp_val;
3454    if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff))
3455       barf("GP-relative data out of range (address = 0x%lx, gp = 0x%lx)", value, gp_val);
3456
3457    instruction = ia64_extract_instruction((Elf64_Xword *)target);
3458    instruction |= (((rel_value >> 0) & 0x07f) << 13)            /* imm7b */
3459                     | (((rel_value >> 7) & 0x1ff) << 27)        /* imm9d */
3460                     | (((rel_value >> 16) & 0x01f) << 22)       /* imm5c */
3461                     | ((Elf64_Xword)(rel_value < 0) << 36);     /* s */
3462    ia64_deposit_instruction((Elf64_Xword *)target, instruction);
3463 }
3464
3465 static void
3466 ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc)
3467 {
3468    Elf64_Xword instruction;
3469    Elf64_Sxword rel_value;
3470    Elf_Addr entry;
3471
3472    entry = allocatePLTEntry(value, oc);
3473
3474    rel_value = (entry >> 4) - (target >> 4);
3475    if ((rel_value > 0xfffff) || (rel_value < -0xfffff))
3476       barf("PLT entry too far away (entry = 0x%lx, target = 0x%lx)", entry, target);
3477
3478    instruction = ia64_extract_instruction((Elf64_Xword *)target);
3479    instruction |= ((rel_value & 0xfffff) << 13)                 /* imm20b */
3480                     | ((Elf64_Xword)(rel_value < 0) << 36);     /* s */
3481    ia64_deposit_instruction((Elf64_Xword *)target, instruction);
3482 }
3483
3484 #endif /* ia64 */
3485
3486 /*
3487  * PowerPC ELF specifics
3488  */
3489
3490 #ifdef powerpc_HOST_ARCH
3491
3492 static int ocAllocateJumpIslands_ELF( ObjectCode *oc )
3493 {
3494   Elf_Ehdr *ehdr;
3495   Elf_Shdr* shdr;
3496   int i;
3497
3498   ehdr = (Elf_Ehdr *) oc->image;
3499   shdr = (Elf_Shdr *) ( ((char *)oc->image) + ehdr->e_shoff );
3500
3501   for( i = 0; i < ehdr->e_shnum; i++ )
3502     if( shdr[i].sh_type == SHT_SYMTAB )
3503       break;
3504
3505   if( i == ehdr->e_shnum )
3506   {
3507     errorBelch( "This ELF file contains no symtab" );
3508     return 0;
3509   }
3510
3511   if( shdr[i].sh_entsize != sizeof( Elf_Sym ) )
3512   {
3513     errorBelch( "The entry size (%d) of the symtab isn't %d\n",
3514       shdr[i].sh_entsize, sizeof( Elf_Sym ) );
3515
3516     return 0;
3517   }
3518
3519   return ocAllocateJumpIslands( oc, shdr[i].sh_size / sizeof( Elf_Sym ), 0 );
3520 }
3521
3522 #endif /* powerpc */
3523
3524 #endif /* ELF */
3525
3526 /* --------------------------------------------------------------------------
3527  * Mach-O specifics
3528  * ------------------------------------------------------------------------*/
3529
3530 #if defined(OBJFORMAT_MACHO)
3531
3532 /*
3533   Support for MachO linking on Darwin/MacOS X
3534   by Wolfgang Thaller (wolfgang.thaller@gmx.net)
3535
3536   I hereby formally apologize for the hackish nature of this code.
3537   Things that need to be done:
3538   *) implement ocVerifyImage_MachO
3539   *) add still more sanity checks.
3540 */
3541
3542 #ifdef powerpc_HOST_ARCH
3543 static int ocAllocateJumpIslands_MachO(ObjectCode* oc)
3544 {
3545     struct mach_header *header = (struct mach_header *) oc->image;
3546     struct load_command *lc = (struct load_command *) (header + 1);
3547     unsigned i;
3548
3549     for( i = 0; i < header->ncmds; i++ )
3550     {
3551         if( lc->cmd == LC_SYMTAB )
3552         {
3553                 // Find out the first and last undefined external
3554                 // symbol, so we don't have to allocate too many
3555                 // jump islands.
3556             struct symtab_command *symLC = (struct symtab_command *) lc;
3557             unsigned min = symLC->nsyms, max = 0;
3558             struct nlist *nlist =
3559                 symLC ? (struct nlist*) ((char*) oc->image + symLC->symoff)
3560                       : NULL;
3561             for(i=0;i<symLC->nsyms;i++)
3562             {
3563                 if(nlist[i].n_type & N_STAB)
3564                     ;
3565                 else if(nlist[i].n_type & N_EXT)
3566                 {
3567                     if((nlist[i].n_type & N_TYPE) == N_UNDF
3568                         && (nlist[i].n_value == 0))
3569                     {
3570                         if(i < min)
3571                             min = i;
3572                         if(i > max)
3573                             max = i;
3574                     }
3575                 }
3576             }
3577             if(max >= min)
3578                 return ocAllocateJumpIslands(oc, max - min + 1, min);
3579
3580             break;
3581         }
3582
3583         lc = (struct load_command *) ( ((char *)lc) + lc->cmdsize );
3584     }
3585     return ocAllocateJumpIslands(oc,0,0);
3586 }
3587 #endif
3588
3589 static int ocVerifyImage_MachO(ObjectCode* oc STG_UNUSED)
3590 {
3591     // FIXME: do some verifying here
3592     return 1;
3593 }
3594
3595 static int resolveImports(
3596     ObjectCode* oc,
3597     char *image,
3598     struct symtab_command *symLC,
3599     struct section *sect,    // ptr to lazy or non-lazy symbol pointer section
3600     unsigned long *indirectSyms,
3601     struct nlist *nlist)
3602 {
3603     unsigned i;
3604
3605     for(i=0;i*4<sect->size;i++)
3606     {
3607         // according to otool, reserved1 contains the first index into the indirect symbol table
3608         struct nlist *symbol = &nlist[indirectSyms[sect->reserved1+i]];
3609         char *nm = image + symLC->stroff + symbol->n_un.n_strx;
3610         void *addr = NULL;
3611
3612         if((symbol->n_type & N_TYPE) == N_UNDF
3613             && (symbol->n_type & N_EXT) && (symbol->n_value != 0))
3614             addr = (void*) (symbol->n_value);
3615         else if((addr = lookupLocalSymbol(oc,nm)) != NULL)
3616             ;
3617         else
3618             addr = lookupSymbol(nm);
3619         if(!addr)
3620         {
3621             errorBelch("\n%s: unknown symbol `%s'", oc->fileName, nm);
3622             return 0;
3623         }
3624         ASSERT(addr);
3625         checkProddableBlock(oc,((void**)(image + sect->offset)) + i);
3626         ((void**)(image + sect->offset))[i] = addr;
3627     }
3628
3629     return 1;
3630 }
3631
3632 static unsigned long relocateAddress(
3633     ObjectCode* oc,
3634     int nSections,
3635     struct section* sections,
3636     unsigned long address)
3637 {
3638     int i;
3639     for(i = 0; i < nSections; i++)
3640     {
3641         if(sections[i].addr <= address
3642             && address < sections[i].addr + sections[i].size)
3643         {
3644             return (unsigned long)oc->image
3645                     + sections[i].offset + address - sections[i].addr;
3646         }
3647     }
3648     barf("Invalid Mach-O file:"
3649          "Address out of bounds while relocating object file");
3650     return 0;
3651 }
3652
3653 static int relocateSection(
3654     ObjectCode* oc,
3655     char *image,
3656     struct symtab_command *symLC, struct nlist *nlist,
3657     int nSections, struct section* sections, struct section *sect)
3658 {
3659     struct relocation_info *relocs;
3660     int i,n;
3661
3662     if(!strcmp(sect->sectname,"__la_symbol_ptr"))
3663         return 1;
3664     else if(!strcmp(sect->sectname,"__nl_symbol_ptr"))
3665         return 1;
3666     else if(!strcmp(sect->sectname,"__la_sym_ptr2"))
3667         return 1;
3668     else if(!strcmp(sect->sectname,"__la_sym_ptr3"))
3669         return 1;
3670
3671     n = sect->nreloc;
3672     relocs = (struct relocation_info*) (image + sect->reloff);
3673
3674     for(i=0;i<n;i++)
3675     {
3676         if(relocs[i].r_address & R_SCATTERED)
3677         {
3678             struct scattered_relocation_info *scat =
3679                 (struct scattered_relocation_info*) &relocs[i];
3680
3681             if(!scat->r_pcrel)
3682             {
3683                 if(scat->r_length == 2)
3684                 {
3685                     unsigned long word = 0;
3686                     unsigned long* wordPtr = (unsigned long*) (image + sect->offset + scat->r_address);
3687                     checkProddableBlock(oc,wordPtr);
3688
3689                     // Note on relocation types:
3690                     // i386 uses the GENERIC_RELOC_* types,
3691                     // while ppc uses special PPC_RELOC_* types.
3692                     // *_RELOC_VANILLA and *_RELOC_PAIR have the same value
3693                     // in both cases, all others are different.
3694                     // Therefore, we use GENERIC_RELOC_VANILLA
3695                     // and GENERIC_RELOC_PAIR instead of the PPC variants,
3696                     // and use #ifdefs for the other types.
3697
3698                     // Step 1: Figure out what the relocated value should be
3699                     if(scat->r_type == GENERIC_RELOC_VANILLA)
3700                     {
3701                         word = *wordPtr + (unsigned long) relocateAddress(
3702                                                                 oc,
3703                                                                 nSections,
3704                                                                 sections,
3705                                                                 scat->r_value)
3706                                         - scat->r_value;
3707                     }
3708 #ifdef powerpc_HOST_ARCH
3709                     else if(scat->r_type == PPC_RELOC_SECTDIFF
3710                         || scat->r_type == PPC_RELOC_LO16_SECTDIFF
3711                         || scat->r_type == PPC_RELOC_HI16_SECTDIFF
3712                         || scat->r_type == PPC_RELOC_HA16_SECTDIFF)
3713 #else
3714                     else if(scat->r_type == GENERIC_RELOC_SECTDIFF)
3715 #endif
3716                     {
3717                         struct scattered_relocation_info *pair =
3718                                 (struct scattered_relocation_info*) &relocs[i+1];
3719
3720                         if(!pair->r_scattered || pair->r_type != GENERIC_RELOC_PAIR)
3721                             barf("Invalid Mach-O file: "
3722                                  "RELOC_*_SECTDIFF not followed by RELOC_PAIR");
3723
3724                         word = (unsigned long)
3725                                (relocateAddress(oc, nSections, sections, scat->r_value)
3726                               - relocateAddress(oc, nSections, sections, pair->r_value));
3727                         i++;
3728                     }
3729 #ifdef powerpc_HOST_ARCH
3730                     else if(scat->r_type == PPC_RELOC_HI16
3731                          || scat->r_type == PPC_RELOC_LO16
3732                          || scat->r_type == PPC_RELOC_HA16
3733                          || scat->r_type == PPC_RELOC_LO14)
3734                     {   // these are generated by label+offset things
3735                         struct relocation_info *pair = &relocs[i+1];
3736                         if((pair->r_address & R_SCATTERED) || pair->r_type != PPC_RELOC_PAIR)
3737                             barf("Invalid Mach-O file: "
3738                                  "PPC_RELOC_* not followed by PPC_RELOC_PAIR");
3739
3740                         if(scat->r_type == PPC_RELOC_LO16)
3741                         {
3742                             word = ((unsigned short*) wordPtr)[1];
3743                             word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
3744                         }
3745                         else if(scat->r_type == PPC_RELOC_LO14)
3746                         {
3747                             barf("Unsupported Relocation: PPC_RELOC_LO14");
3748                             word = ((unsigned short*) wordPtr)[1] & 0xFFFC;
3749                             word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
3750                         }
3751                         else if(scat->r_type == PPC_RELOC_HI16)
3752                         {
3753                             word = ((unsigned short*) wordPtr)[1] << 16;
3754                             word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
3755                         }
3756                         else if(scat->r_type == PPC_RELOC_HA16)
3757                         {
3758                             word = ((unsigned short*) wordPtr)[1] << 16;
3759                             word += ((short)relocs[i+1].r_address & (short)0xFFFF);
3760                         }
3761
3762
3763                         word += (unsigned long) relocateAddress(oc, nSections, sections, scat->r_value)
3764                                                 - scat->r_value;
3765
3766                         i++;
3767                     }
3768  #endif
3769                     else
3770                         continue;  // ignore the others
3771
3772 #ifdef powerpc_HOST_ARCH
3773                     if(scat->r_type == GENERIC_RELOC_VANILLA
3774                         || scat->r_type == PPC_RELOC_SECTDIFF)
3775 #else
3776                     if(scat->r_type == GENERIC_RELOC_VANILLA
3777                         || scat->r_type == GENERIC_RELOC_SECTDIFF)
3778 #endif
3779                     {
3780                         *wordPtr = word;
3781                     }
3782 #ifdef powerpc_HOST_ARCH
3783                     else if(scat->r_type == PPC_RELOC_LO16_SECTDIFF || scat->r_type == PPC_RELOC_LO16)
3784                     {
3785                         ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
3786                     }
3787                     else if(scat->r_type == PPC_RELOC_HI16_SECTDIFF || scat->r_type == PPC_RELOC_HI16)
3788                     {
3789                         ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
3790                     }
3791                     else if(scat->r_type == PPC_RELOC_HA16_SECTDIFF || scat->r_type == PPC_RELOC_HA16)
3792                     {
3793                         ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
3794                             + ((word & (1<<15)) ? 1 : 0);
3795                     }
3796 #endif
3797                 }
3798             }
3799
3800             continue; // FIXME: I hope it's OK to ignore all the others.
3801         }
3802         else
3803         {
3804             struct relocation_info *reloc = &relocs[i];
3805             if(reloc->r_pcrel && !reloc->r_extern)
3806                 continue;
3807
3808             if(reloc->r_length == 2)
3809             {
3810                 unsigned long word = 0;
3811 #ifdef powerpc_HOST_ARCH
3812                 unsigned long jumpIsland = 0;
3813                 long offsetToJumpIsland = 0xBADBAD42; // initialise to bad value
3814                                                       // to avoid warning and to catch
3815                                                       // bugs.
3816 #endif
3817
3818                 unsigned long* wordPtr = (unsigned long*) (image + sect->offset + reloc->r_address);
3819                 checkProddableBlock(oc,wordPtr);
3820
3821                 if(reloc->r_type == GENERIC_RELOC_VANILLA)
3822                 {
3823                     word = *wordPtr;
3824                 }
3825 #ifdef powerpc_HOST_ARCH
3826                 else if(reloc->r_type == PPC_RELOC_LO16)
3827                 {
3828                     word = ((unsigned short*) wordPtr)[1];
3829                     word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
3830                 }
3831                 else if(reloc->r_type == PPC_RELOC_HI16)
3832                 {
3833                     word = ((unsigned short*) wordPtr)[1] << 16;
3834                     word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
3835                 }
3836                 else if(reloc->r_type == PPC_RELOC_HA16)
3837                 {
3838                     word = ((unsigned short*) wordPtr)[1] << 16;
3839                     word += ((short)relocs[i+1].r_address & (short)0xFFFF);
3840                 }
3841                 else if(reloc->r_type == PPC_RELOC_BR24)
3842                 {
3843                     word = *wordPtr;
3844                     word = (word & 0x03FFFFFC) | ((word & 0x02000000) ? 0xFC000000 : 0);
3845                 }
3846 #endif
3847
3848                 if(!reloc->r_extern)
3849                 {
3850                     long delta =
3851                         sections[reloc->r_symbolnum-1].offset
3852                         - sections[reloc->r_symbolnum-1].addr
3853                         + ((long) image);
3854
3855                     word += delta;
3856                 }
3857                 else
3858                 {
3859                     struct nlist *symbol = &nlist[reloc->r_symbolnum];
3860                     char *nm = image + symLC->stroff + symbol->n_un.n_strx;
3861                     void *symbolAddress = lookupSymbol(nm);
3862                     if(!symbolAddress)
3863                     {
3864                         errorBelch("\nunknown symbol `%s'", nm);
3865                         return 0;
3866                     }
3867
3868                     if(reloc->r_pcrel)
3869                     {
3870 #ifdef powerpc_HOST_ARCH
3871                             // In the .o file, this should be a relative jump to NULL
3872                             // and we'll change it to a relative jump to the symbol
3873                         ASSERT(-word == reloc->r_address);
3874                         jumpIsland = makeJumpIsland(oc,reloc->r_symbolnum,(unsigned long) symbolAddress);
3875                         if(jumpIsland != 0)
3876                         {
3877                             offsetToJumpIsland = word + jumpIsland
3878                                 - (((long)image) + sect->offset - sect->addr);
3879                         }
3880 #endif
3881                         word += (unsigned long) symbolAddress
3882                                 - (((long)image) + sect->offset - sect->addr);
3883                     }
3884                     else
3885                     {
3886                         word += (unsigned long) symbolAddress;
3887                     }
3888                 }
3889
3890                 if(reloc->r_type == GENERIC_RELOC_VANILLA)
3891                 {
3892                     *wordPtr = word;
3893                     continue;
3894                 }
3895 #ifdef powerpc_HOST_ARCH
3896                 else if(reloc->r_type == PPC_RELOC_LO16)
3897                 {
3898                     ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
3899                     i++; continue;
3900                 }
3901                 else if(reloc->r_type == PPC_RELOC_HI16)
3902                 {
3903                     ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
3904                     i++; continue;
3905                 }
3906                 else if(reloc->r_type == PPC_RELOC_HA16)
3907                 {
3908                     ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
3909                         + ((word & (1<<15)) ? 1 : 0);
3910                     i++; continue;
3911                 }
3912                 else if(reloc->r_type == PPC_RELOC_BR24)
3913                 {
3914                     if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
3915                     {
3916                         // The branch offset is too large.
3917                         // Therefore, we try to use a jump island.
3918                         if(jumpIsland == 0)
3919                         {
3920                             barf("unconditional relative branch out of range: "
3921                                  "no jump island available");
3922                         }
3923
3924                         word = offsetToJumpIsland;
3925                         if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
3926                             barf("unconditional relative branch out of range: "
3927                                  "jump island out of range");
3928                     }
3929                     *wordPtr = (*wordPtr & 0xFC000003) | (word & 0x03FFFFFC);
3930                     continue;
3931                 }
3932 #endif
3933             }
3934             barf("\nunknown relocation %d",reloc->r_type);
3935             return 0;
3936         }
3937     }
3938     return 1;
3939 }
3940
3941 static int ocGetNames_MachO(ObjectCode* oc)
3942 {
3943     char *image = (char*) oc->image;
3944     struct mach_header *header = (struct mach_header*) image;
3945     struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
3946     unsigned i,curSymbol = 0;
3947     struct segment_command *segLC = NULL;
3948     struct section *sections;
3949     struct symtab_command *symLC = NULL;
3950     struct nlist *nlist;
3951     unsigned long commonSize = 0;
3952     char    *commonStorage = NULL;
3953     unsigned long commonCounter;
3954
3955     for(i=0;i<header->ncmds;i++)
3956     {
3957         if(lc->cmd == LC_SEGMENT)
3958             segLC = (struct segment_command*) lc;
3959         else if(lc->cmd == LC_SYMTAB)
3960             symLC = (struct symtab_command*) lc;
3961         lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
3962     }
3963
3964     sections = (struct section*) (segLC+1);
3965     nlist = symLC ? (struct nlist*) (image + symLC->symoff)
3966                   : NULL;
3967
3968     for(i=0;i<segLC->nsects;i++)
3969     {
3970         if(sections[i].size == 0)
3971             continue;
3972
3973         if((sections[i].flags & SECTION_TYPE) == S_ZEROFILL)
3974         {
3975             char * zeroFillArea = stgCallocBytes(1,sections[i].size,
3976                                       "ocGetNames_MachO(common symbols)");
3977             sections[i].offset = zeroFillArea - image;
3978         }
3979
3980         if(!strcmp(sections[i].sectname,"__text"))
3981             addSection(oc, SECTIONKIND_CODE_OR_RODATA,
3982                 (void*) (image + sections[i].offset),
3983                 (void*) (image + sections[i].offset + sections[i].size));
3984         else if(!strcmp(sections[i].sectname,"__const"))
3985             addSection(oc, SECTIONKIND_RWDATA,
3986                 (void*) (image + sections[i].offset),
3987                 (void*) (image + sections[i].offset + sections[i].size));
3988         else if(!strcmp(sections[i].sectname,"__data"))
3989             addSection(oc, SECTIONKIND_RWDATA,
3990                 (void*) (image + sections[i].offset),
3991                 (void*) (image + sections[i].offset + sections[i].size));
3992         else if(!strcmp(sections[i].sectname,"__bss")
3993                 || !strcmp(sections[i].sectname,"__common"))
3994             addSection(oc, SECTIONKIND_RWDATA,
3995                 (void*) (image + sections[i].offset),
3996                 (void*) (image + sections[i].offset + sections[i].size));
3997
3998         addProddableBlock(oc, (void*) (image + sections[i].offset),
3999                                         sections[i].size);
4000     }
4001
4002         // count external symbols defined here
4003     oc->n_symbols = 0;
4004     if(symLC)
4005     {
4006         for(i=0;i<symLC->nsyms;i++)
4007         {
4008             if(nlist[i].n_type & N_STAB)
4009                 ;
4010             else if(nlist[i].n_type & N_EXT)
4011             {
4012                 if((nlist[i].n_type & N_TYPE) == N_UNDF
4013                     && (nlist[i].n_value != 0))
4014                 {
4015                     commonSize += nlist[i].n_value;
4016                     oc->n_symbols++;
4017                 }
4018                 else if((nlist[i].n_type & N_TYPE) == N_SECT)
4019                     oc->n_symbols++;
4020             }
4021         }
4022     }
4023     oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
4024                                    "ocGetNames_MachO(oc->symbols)");
4025
4026     if(symLC)
4027     {
4028         for(i=0;i<symLC->nsyms;i++)
4029         {
4030             if(nlist[i].n_type & N_STAB)
4031                 ;
4032             else if((nlist[i].n_type & N_TYPE) == N_SECT)
4033             {
4034                 if(nlist[i].n_type & N_EXT)
4035                 {
4036                     char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
4037                     ghciInsertStrHashTable(oc->fileName, symhash, nm,
4038                                             image
4039                                             + sections[nlist[i].n_sect-1].offset
4040                                             - sections[nlist[i].n_sect-1].addr
4041                                             + nlist[i].n_value);
4042                     oc->symbols[curSymbol++] = nm;
4043                 }
4044                 else
4045                 {
4046                     char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
4047                     ghciInsertStrHashTable(oc->fileName, oc->lochash, nm,
4048                                             image
4049                                             + sections[nlist[i].n_sect-1].offset
4050                                             - sections[nlist[i].n_sect-1].addr
4051                                             + nlist[i].n_value);
4052                 }
4053             }
4054         }
4055     }
4056
4057     commonStorage = stgCallocBytes(1,commonSize,"ocGetNames_MachO(common symbols)");
4058     commonCounter = (unsigned long)commonStorage;
4059     if(symLC)
4060     {
4061         for(i=0;i<symLC->nsyms;i++)
4062         {
4063             if((nlist[i].n_type & N_TYPE) == N_UNDF
4064                     && (nlist[i].n_type & N_EXT) && (nlist[i].n_value != 0))
4065             {
4066                 char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
4067                 unsigned long sz = nlist[i].n_value;
4068
4069                 nlist[i].n_value = commonCounter;
4070
4071                 ghciInsertStrHashTable(oc->fileName, symhash, nm,
4072                                        (void*)commonCounter);
4073                 oc->symbols[curSymbol++] = nm;
4074
4075                 commonCounter += sz;
4076             }
4077         }
4078     }
4079     return 1;
4080 }
4081
4082 static int ocResolve_MachO(ObjectCode* oc)
4083 {
4084     char *image = (char*) oc->image;
4085     struct mach_header *header = (struct mach_header*) image;
4086     struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
4087     unsigned i;
4088     struct segment_command *segLC = NULL;
4089     struct section *sections, *la_ptrs = NULL, *nl_ptrs = NULL;
4090     struct symtab_command *symLC = NULL;
4091     struct dysymtab_command *dsymLC = NULL;
4092     struct nlist *nlist;
4093
4094     for(i=0;i<header->ncmds;i++)
4095     {
4096         if(lc->cmd == LC_SEGMENT)
4097             segLC = (struct segment_command*) lc;
4098         else if(lc->cmd == LC_SYMTAB)
4099             symLC = (struct symtab_command*) lc;
4100         else if(lc->cmd == LC_DYSYMTAB)
4101             dsymLC = (struct dysymtab_command*) lc;
4102         lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
4103     }
4104
4105     sections = (struct section*) (segLC+1);
4106     nlist = symLC ? (struct nlist*) (image + symLC->symoff)
4107                   : NULL;
4108
4109     for(i=0;i<segLC->nsects;i++)
4110     {
4111         if(!strcmp(sections[i].sectname,"__la_symbol_ptr"))
4112             la_ptrs = &sections[i];
4113         else if(!strcmp(sections[i].sectname,"__nl_symbol_ptr"))
4114             nl_ptrs = &sections[i];
4115         else if(!strcmp(sections[i].sectname,"__la_sym_ptr2"))
4116             la_ptrs = &sections[i];
4117         else if(!strcmp(sections[i].sectname,"__la_sym_ptr3"))
4118             la_ptrs = &sections[i];
4119     }
4120
4121     if(dsymLC)
4122     {
4123         unsigned long *indirectSyms
4124             = (unsigned long*) (image + dsymLC->indirectsymoff);
4125
4126         if(la_ptrs)
4127             if(!resolveImports(oc,image,symLC,la_ptrs,indirectSyms,nlist))
4128                 return 0;
4129         if(nl_ptrs)
4130             if(!resolveImports(oc,image,symLC,nl_ptrs,indirectSyms,nlist))
4131                 return 0;
4132     }
4133
4134     for(i=0;i<segLC->nsects;i++)
4135     {
4136         if(!relocateSection(oc,image,symLC,nlist,segLC->nsects,sections,&sections[i]))
4137             return 0;
4138     }
4139
4140     /* Free the local symbol table; we won't need it again. */
4141     freeHashTable(oc->lochash, NULL);
4142     oc->lochash = NULL;
4143
4144 #if defined (powerpc_HOST_ARCH)
4145     ocFlushInstructionCache( oc );
4146 #endif
4147
4148     return 1;
4149 }
4150
4151 #ifdef powerpc_HOST_ARCH
4152 /*
4153  * The Mach-O object format uses leading underscores. But not everywhere.
4154  * There is a small number of runtime support functions defined in
4155  * libcc_dynamic.a whose name does not have a leading underscore.
4156  * As a consequence, we can't get their address from C code.
4157  * We have to use inline assembler just to take the address of a function.
4158  * Yuck.
4159  */
4160
4161 static void machoInitSymbolsWithoutUnderscore()
4162 {
4163     extern void* symbolsWithoutUnderscore[];
4164     void **p = symbolsWithoutUnderscore;
4165     __asm__ volatile(".globl _symbolsWithoutUnderscore\n.data\n_symbolsWithoutUnderscore:");
4166
4167 #undef Sym
4168 #define Sym(x)  \
4169     __asm__ volatile(".long " # x);
4170
4171     RTS_MACHO_NOUNDERLINE_SYMBOLS
4172
4173     __asm__ volatile(".text");
4174
4175 #undef Sym
4176 #define Sym(x)  \
4177     ghciInsertStrHashTable("(GHCi built-in symbols)", symhash, #x, *p++);
4178
4179     RTS_MACHO_NOUNDERLINE_SYMBOLS
4180
4181 #undef Sym
4182 }
4183 #endif
4184
4185 /*
4186  * Figure out by how much to shift the entire Mach-O file in memory
4187  * when loading so that its single segment ends up 16-byte-aligned
4188  */
4189 static int machoGetMisalignment( FILE * f )
4190 {
4191     struct mach_header header;
4192     int misalignment;
4193
4194     fread(&header, sizeof(header), 1, f);
4195     rewind(f);
4196
4197     if(header.magic != MH_MAGIC)
4198         return 0;
4199
4200     misalignment = (header.sizeofcmds + sizeof(header))
4201                     & 0xF;
4202
4203     return misalignment ? (16 - misalignment) : 0;
4204 }
4205
4206 #endif