1d3a60239379b43abd3261d9c5319d300bceb2b5
[ghc-hetmet.git] / 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 #  include <mach-o/ppc/reloc.h>
82 #  define OBJFORMAT_MACHO
83 #  include <mach-o/loader.h>
84 #  include <mach-o/nlist.h>
85 #  include <mach-o/reloc.h>
86 #  include <mach-o/dyld.h>
87 #endif
88
89 /* Hash table mapping symbol names to Symbol */
90 static /*Str*/HashTable *symhash;
91
92 /* List of currently loaded objects */
93 ObjectCode *objects = NULL;     /* initially empty */
94
95 #if defined(OBJFORMAT_ELF)
96 static int ocVerifyImage_ELF    ( ObjectCode* oc );
97 static int ocGetNames_ELF       ( ObjectCode* oc );
98 static int ocResolve_ELF        ( ObjectCode* oc );
99 #if defined(powerpc_HOST_ARCH)
100 static int ocAllocateJumpIslands_ELF ( ObjectCode* oc );
101 #endif
102 #elif defined(OBJFORMAT_PEi386)
103 static int ocVerifyImage_PEi386 ( ObjectCode* oc );
104 static int ocGetNames_PEi386    ( ObjectCode* oc );
105 static int ocResolve_PEi386     ( ObjectCode* oc );
106 #elif defined(OBJFORMAT_MACHO)
107 static int ocAllocateJumpIslands_MachO ( ObjectCode* oc );
108 static int ocVerifyImage_MachO    ( ObjectCode* oc );
109 static int ocGetNames_MachO       ( ObjectCode* oc );
110 static int ocResolve_MachO        ( ObjectCode* oc );
111
112 static void machoInitSymbolsWithoutUnderscore( void );
113 #endif
114
115 /* -----------------------------------------------------------------------------
116  * Built-in symbols from the RTS
117  */
118
119 typedef struct _RtsSymbolVal {
120     char   *lbl;
121     void   *addr;
122 } RtsSymbolVal;
123
124
125 #if !defined(PAR)
126 #define Maybe_ForeignObj        SymX(mkForeignObjzh_fast)
127
128 #define Maybe_Stable_Names      SymX(mkWeakzh_fast)                     \
129                                 SymX(makeStableNamezh_fast)             \
130                                 SymX(finalizzeWeakzh_fast)
131 #else
132 /* These are not available in GUM!!! -- HWL */
133 #define Maybe_ForeignObj
134 #define Maybe_Stable_Names
135 #endif
136
137 #if !defined (mingw32_HOST_OS)
138 #define RTS_POSIX_ONLY_SYMBOLS                  \
139       SymX(stg_sig_install)                     \
140       Sym(nocldstop)
141 #endif
142
143 #if defined (cygwin32_HOST_OS)
144 #define RTS_MINGW_ONLY_SYMBOLS /**/
145 /* Don't have the ability to read import libs / archives, so
146  * we have to stupidly list a lot of what libcygwin.a
147  * exports; sigh.
148  */
149 #define RTS_CYGWIN_ONLY_SYMBOLS                 \
150       SymX(regfree)                             \
151       SymX(regexec)                             \
152       SymX(regerror)                            \
153       SymX(regcomp)                             \
154       SymX(__errno)                             \
155       SymX(access)                              \
156       SymX(chmod)                               \
157       SymX(chdir)                               \
158       SymX(close)                               \
159       SymX(creat)                               \
160       SymX(dup)                                 \
161       SymX(dup2)                                \
162       SymX(fstat)                               \
163       SymX(fcntl)                               \
164       SymX(getcwd)                              \
165       SymX(getenv)                              \
166       SymX(lseek)                               \
167       SymX(open)                                \
168       SymX(fpathconf)                           \
169       SymX(pathconf)                            \
170       SymX(stat)                                \
171       SymX(pow)                                 \
172       SymX(tanh)                                \
173       SymX(cosh)                                \
174       SymX(sinh)                                \
175       SymX(atan)                                \
176       SymX(acos)                                \
177       SymX(asin)                                \
178       SymX(tan)                                 \
179       SymX(cos)                                 \
180       SymX(sin)                                 \
181       SymX(exp)                                 \
182       SymX(log)                                 \
183       SymX(sqrt)                                \
184       SymX(localtime_r)                         \
185       SymX(gmtime_r)                            \
186       SymX(mktime)                              \
187       Sym(_imp___tzname)                        \
188       SymX(gettimeofday)                        \
189       SymX(timezone)                            \
190       SymX(tcgetattr)                           \
191       SymX(tcsetattr)                           \
192       SymX(memcpy)                              \
193       SymX(memmove)                             \
194       SymX(realloc)                             \
195       SymX(malloc)                              \
196       SymX(free)                                \
197       SymX(fork)                                \
198       SymX(lstat)                               \
199       SymX(isatty)                              \
200       SymX(mkdir)                               \
201       SymX(opendir)                             \
202       SymX(readdir)                             \
203       SymX(rewinddir)                           \
204       SymX(closedir)                            \
205       SymX(link)                                \
206       SymX(mkfifo)                              \
207       SymX(pipe)                                \
208       SymX(read)                                \
209       SymX(rename)                              \
210       SymX(rmdir)                               \
211       SymX(select)                              \
212       SymX(system)                              \
213       SymX(write)                               \
214       SymX(strcmp)                              \
215       SymX(strcpy)                              \
216       SymX(strncpy)                             \
217       SymX(strerror)                            \
218       SymX(sigaddset)                           \
219       SymX(sigemptyset)                         \
220       SymX(sigprocmask)                         \
221       SymX(umask)                               \
222       SymX(uname)                               \
223       SymX(unlink)                              \
224       SymX(utime)                               \
225       SymX(waitpid)
226
227 #elif !defined(mingw32_HOST_OS)
228 #define RTS_MINGW_ONLY_SYMBOLS /**/
229 #define RTS_CYGWIN_ONLY_SYMBOLS /**/
230 #else /* defined(mingw32_HOST_OS) */
231 #define RTS_POSIX_ONLY_SYMBOLS  /**/
232 #define RTS_CYGWIN_ONLY_SYMBOLS /**/
233
234 /* Extra syms gen'ed by mingw-2's gcc-3.2: */
235 #if __GNUC__>=3
236 #define RTS_MINGW_EXTRA_SYMS                    \
237       Sym(_imp____mb_cur_max)                   \
238       Sym(_imp___pctype)
239 #else
240 #define RTS_MINGW_EXTRA_SYMS
241 #endif
242
243 /* These are statically linked from the mingw libraries into the ghc
244    executable, so we have to employ this hack. */
245 #define RTS_MINGW_ONLY_SYMBOLS                  \
246       SymX(asyncReadzh_fast)                    \
247       SymX(asyncWritezh_fast)                   \
248       SymX(asyncDoProczh_fast)                  \
249       SymX(memset)                              \
250       SymX(inet_ntoa)                           \
251       SymX(inet_addr)                           \
252       SymX(htonl)                               \
253       SymX(recvfrom)                            \
254       SymX(listen)                              \
255       SymX(bind)                                \
256       SymX(shutdown)                            \
257       SymX(connect)                             \
258       SymX(htons)                               \
259       SymX(ntohs)                               \
260       SymX(getservbyname)                       \
261       SymX(getservbyport)                       \
262       SymX(getprotobynumber)                    \
263       SymX(getprotobyname)                      \
264       SymX(gethostbyname)                       \
265       SymX(gethostbyaddr)                       \
266       SymX(gethostname)                         \
267       SymX(strcpy)                              \
268       SymX(strncpy)                             \
269       SymX(abort)                               \
270       Sym(_alloca)                              \
271       Sym(isxdigit)                             \
272       Sym(isupper)                              \
273       Sym(ispunct)                              \
274       Sym(islower)                              \
275       Sym(isspace)                              \
276       Sym(isprint)                              \
277       Sym(isdigit)                              \
278       Sym(iscntrl)                              \
279       Sym(isalpha)                              \
280       Sym(isalnum)                              \
281       SymX(strcmp)                              \
282       SymX(memmove)                             \
283       SymX(realloc)                             \
284       SymX(malloc)                              \
285       SymX(pow)                                 \
286       SymX(tanh)                                \
287       SymX(cosh)                                \
288       SymX(sinh)                                \
289       SymX(atan)                                \
290       SymX(acos)                                \
291       SymX(asin)                                \
292       SymX(tan)                                 \
293       SymX(cos)                                 \
294       SymX(sin)                                 \
295       SymX(exp)                                 \
296       SymX(log)                                 \
297       SymX(sqrt)                                \
298       SymX(memcpy)                              \
299       SymX(rts_InstallConsoleEvent)             \
300       SymX(rts_ConsoleHandlerDone)              \
301       Sym(mktime)                               \
302       Sym(_imp___timezone)                      \
303       Sym(_imp___tzname)                        \
304       Sym(_imp___iob)                           \
305       Sym(_imp___osver)                         \
306       Sym(localtime)                            \
307       Sym(gmtime)                               \
308       Sym(opendir)                              \
309       Sym(readdir)                              \
310       Sym(rewinddir)                            \
311       RTS_MINGW_EXTRA_SYMS                      \
312       Sym(closedir)
313 #endif
314
315 #ifndef SMP
316 # define MAIN_CAP_SYM SymX(MainCapability)
317 #else
318 # define MAIN_CAP_SYM
319 #endif
320
321 #if !defined(mingw32_HOST_OS)
322 #define RTS_USER_SIGNALS_SYMBOLS \
323    SymX(startSignalHandler) \
324    SymX(setIOManagerPipe)
325 #else
326 #define RTS_USER_SIGNALS_SYMBOLS /* nothing */
327 #endif
328
329 #ifdef TABLES_NEXT_TO_CODE
330 #define RTS_RET_SYMBOLS /* nothing */
331 #else
332 #define RTS_RET_SYMBOLS                         \
333       SymX(stg_enter_ret)                       \
334       SymX(stg_gc_fun_ret)                      \
335       SymX(stg_ap_0_ret)                        \
336       SymX(stg_ap_v_ret)                        \
337       SymX(stg_ap_f_ret)                        \
338       SymX(stg_ap_d_ret)                        \
339       SymX(stg_ap_l_ret)                        \
340       SymX(stg_ap_n_ret)                        \
341       SymX(stg_ap_p_ret)                        \
342       SymX(stg_ap_pv_ret)                       \
343       SymX(stg_ap_pp_ret)                       \
344       SymX(stg_ap_ppv_ret)                      \
345       SymX(stg_ap_ppp_ret)                      \
346       SymX(stg_ap_pppv_ret)                     \
347       SymX(stg_ap_pppp_ret)                     \
348       SymX(stg_ap_ppppp_ret)                    \
349       SymX(stg_ap_pppppp_ret)
350 #endif
351
352 #define RTS_SYMBOLS                             \
353       Maybe_ForeignObj                          \
354       Maybe_Stable_Names                        \
355       Sym(StgReturn)                            \
356       SymX(stg_enter_info)                      \
357       SymX(stg_gc_void_info)                    \
358       SymX(__stg_gc_enter_1)                    \
359       SymX(stg_gc_noregs)                       \
360       SymX(stg_gc_unpt_r1_info)                 \
361       SymX(stg_gc_unpt_r1)                      \
362       SymX(stg_gc_unbx_r1_info)                 \
363       SymX(stg_gc_unbx_r1)                      \
364       SymX(stg_gc_f1_info)                      \
365       SymX(stg_gc_f1)                           \
366       SymX(stg_gc_d1_info)                      \
367       SymX(stg_gc_d1)                           \
368       SymX(stg_gc_l1_info)                      \
369       SymX(stg_gc_l1)                           \
370       SymX(__stg_gc_fun)                        \
371       SymX(stg_gc_fun_info)                     \
372       SymX(stg_gc_gen)                          \
373       SymX(stg_gc_gen_info)                     \
374       SymX(stg_gc_gen_hp)                       \
375       SymX(stg_gc_ut)                           \
376       SymX(stg_gen_yield)                       \
377       SymX(stg_yield_noregs)                    \
378       SymX(stg_yield_to_interpreter)            \
379       SymX(stg_gen_block)                       \
380       SymX(stg_block_noregs)                    \
381       SymX(stg_block_1)                         \
382       SymX(stg_block_takemvar)                  \
383       SymX(stg_block_putmvar)                   \
384       SymX(stg_seq_frame_info)                  \
385       MAIN_CAP_SYM                              \
386       SymX(MallocFailHook)                      \
387       SymX(OnExitHook)                          \
388       SymX(OutOfHeapHook)                       \
389       SymX(StackOverflowHook)                   \
390       SymX(__encodeDouble)                      \
391       SymX(__encodeFloat)                       \
392       SymX(addDLL)                              \
393       SymX(__gmpn_gcd_1)                        \
394       SymX(__gmpz_cmp)                          \
395       SymX(__gmpz_cmp_si)                       \
396       SymX(__gmpz_cmp_ui)                       \
397       SymX(__gmpz_get_si)                       \
398       SymX(__gmpz_get_ui)                       \
399       SymX(__int_encodeDouble)                  \
400       SymX(__int_encodeFloat)                   \
401       SymX(andIntegerzh_fast)                   \
402       SymX(atomicallyzh_fast)                   \
403       SymX(barf)                                \
404       SymX(debugBelch)                          \
405       SymX(errorBelch)                          \
406       SymX(blockAsyncExceptionszh_fast)         \
407       SymX(catchzh_fast)                        \
408       SymX(catchRetryzh_fast)                   \
409       SymX(catchSTMzh_fast)                     \
410       SymX(closure_flags)                       \
411       SymX(cmp_thread)                          \
412       SymX(cmpIntegerzh_fast)                   \
413       SymX(cmpIntegerIntzh_fast)                \
414       SymX(complementIntegerzh_fast)            \
415       SymX(createAdjustor)                      \
416       SymX(decodeDoublezh_fast)                 \
417       SymX(decodeFloatzh_fast)                  \
418       SymX(defaultsHook)                        \
419       SymX(delayzh_fast)                        \
420       SymX(deRefWeakzh_fast)                    \
421       SymX(deRefStablePtrzh_fast)               \
422       SymX(divExactIntegerzh_fast)              \
423       SymX(divModIntegerzh_fast)                \
424       SymX(forkzh_fast)                         \
425       SymX(forkProcess)                         \
426       SymX(forkOS_createThread)                 \
427       SymX(freeHaskellFunctionPtr)              \
428       SymX(freeStablePtr)                       \
429       SymX(gcdIntegerzh_fast)                   \
430       SymX(gcdIntegerIntzh_fast)                \
431       SymX(gcdIntzh_fast)                       \
432       SymX(genSymZh)                            \
433       SymX(genericRaise)                        \
434       SymX(getProgArgv)                         \
435       SymX(getStablePtr)                        \
436       SymX(hs_init)                             \
437       SymX(hs_exit)                             \
438       SymX(hs_set_argv)                         \
439       SymX(hs_add_root)                         \
440       SymX(hs_perform_gc)                       \
441       SymX(hs_free_stable_ptr)                  \
442       SymX(hs_free_fun_ptr)                     \
443       SymX(initLinker)                          \
444       SymX(int2Integerzh_fast)                  \
445       SymX(integer2Intzh_fast)                  \
446       SymX(integer2Wordzh_fast)                 \
447       SymX(isCurrentThreadBoundzh_fast)         \
448       SymX(isDoubleDenormalized)                \
449       SymX(isDoubleInfinite)                    \
450       SymX(isDoubleNaN)                         \
451       SymX(isDoubleNegativeZero)                \
452       SymX(isEmptyMVarzh_fast)                  \
453       SymX(isFloatDenormalized)                 \
454       SymX(isFloatInfinite)                     \
455       SymX(isFloatNaN)                          \
456       SymX(isFloatNegativeZero)                 \
457       SymX(killThreadzh_fast)                   \
458       SymX(loadObj)                             \
459       SymX(lookupSymbol)                        \
460       SymX(makeStablePtrzh_fast)                \
461       SymX(minusIntegerzh_fast)                 \
462       SymX(mkApUpd0zh_fast)                     \
463       SymX(myThreadIdzh_fast)                   \
464       SymX(labelThreadzh_fast)                  \
465       SymX(newArrayzh_fast)                     \
466       SymX(newBCOzh_fast)                       \
467       SymX(newByteArrayzh_fast)                 \
468       SymX_redirect(newCAF, newDynCAF)          \
469       SymX(newMVarzh_fast)                      \
470       SymX(newMutVarzh_fast)                    \
471       SymX(newTVarzh_fast)                      \
472       SymX(atomicModifyMutVarzh_fast)           \
473       SymX(newPinnedByteArrayzh_fast)           \
474       SymX(orIntegerzh_fast)                    \
475       SymX(performGC)                           \
476       SymX(performMajorGC)                      \
477       SymX(plusIntegerzh_fast)                  \
478       SymX(prog_argc)                           \
479       SymX(prog_argv)                           \
480       SymX(putMVarzh_fast)                      \
481       SymX(quotIntegerzh_fast)                  \
482       SymX(quotRemIntegerzh_fast)               \
483       SymX(raisezh_fast)                        \
484       SymX(raiseIOzh_fast)                      \
485       SymX(readTVarzh_fast)                     \
486       SymX(remIntegerzh_fast)                   \
487       SymX(resetNonBlockingFd)                  \
488       SymX(resumeThread)                        \
489       SymX(resolveObjs)                         \
490       SymX(retryzh_fast)                        \
491       SymX(rts_apply)                           \
492       SymX(rts_checkSchedStatus)                \
493       SymX(rts_eval)                            \
494       SymX(rts_evalIO)                          \
495       SymX(rts_evalLazyIO)                      \
496       SymX(rts_evalStableIO)                    \
497       SymX(rts_eval_)                           \
498       SymX(rts_getBool)                         \
499       SymX(rts_getChar)                         \
500       SymX(rts_getDouble)                       \
501       SymX(rts_getFloat)                        \
502       SymX(rts_getInt)                          \
503       SymX(rts_getInt32)                        \
504       SymX(rts_getPtr)                          \
505       SymX(rts_getFunPtr)                       \
506       SymX(rts_getStablePtr)                    \
507       SymX(rts_getThreadId)                     \
508       SymX(rts_getWord)                         \
509       SymX(rts_getWord32)                       \
510       SymX(rts_lock)                            \
511       SymX(rts_mkBool)                          \
512       SymX(rts_mkChar)                          \
513       SymX(rts_mkDouble)                        \
514       SymX(rts_mkFloat)                         \
515       SymX(rts_mkInt)                           \
516       SymX(rts_mkInt16)                         \
517       SymX(rts_mkInt32)                         \
518       SymX(rts_mkInt64)                         \
519       SymX(rts_mkInt8)                          \
520       SymX(rts_mkPtr)                           \
521       SymX(rts_mkFunPtr)                        \
522       SymX(rts_mkStablePtr)                     \
523       SymX(rts_mkString)                        \
524       SymX(rts_mkWord)                          \
525       SymX(rts_mkWord16)                        \
526       SymX(rts_mkWord32)                        \
527       SymX(rts_mkWord64)                        \
528       SymX(rts_mkWord8)                         \
529       SymX(rts_unlock)                          \
530       SymX(rtsSupportsBoundThreads)             \
531       SymX(run_queue_hd)                        \
532       SymX(__hscore_get_saved_termios)          \
533       SymX(__hscore_set_saved_termios)          \
534       SymX(setProgArgv)                         \
535       SymX(startupHaskell)                      \
536       SymX(shutdownHaskell)                     \
537       SymX(shutdownHaskellAndExit)              \
538       SymX(stable_ptr_table)                    \
539       SymX(stackOverflow)                       \
540       SymX(stg_CAF_BLACKHOLE_info)              \
541       SymX(awakenBlockedQueue)                  \
542       SymX(stg_CHARLIKE_closure)                \
543       SymX(stg_EMPTY_MVAR_info)                 \
544       SymX(stg_IND_STATIC_info)                 \
545       SymX(stg_INTLIKE_closure)                 \
546       SymX(stg_MUT_ARR_PTRS_FROZEN_info)        \
547       SymX(stg_MUT_ARR_PTRS_FROZEN0_info)       \
548       SymX(stg_WEAK_info)                       \
549       SymX(stg_ap_0_info)                       \
550       SymX(stg_ap_v_info)                       \
551       SymX(stg_ap_f_info)                       \
552       SymX(stg_ap_d_info)                       \
553       SymX(stg_ap_l_info)                       \
554       SymX(stg_ap_n_info)                       \
555       SymX(stg_ap_p_info)                       \
556       SymX(stg_ap_pv_info)                      \
557       SymX(stg_ap_pp_info)                      \
558       SymX(stg_ap_ppv_info)                     \
559       SymX(stg_ap_ppp_info)                     \
560       SymX(stg_ap_pppv_info)                    \
561       SymX(stg_ap_pppp_info)                    \
562       SymX(stg_ap_ppppp_info)                   \
563       SymX(stg_ap_pppppp_info)                  \
564       SymX(stg_ap_1_upd_info)                   \
565       SymX(stg_ap_2_upd_info)                   \
566       SymX(stg_ap_3_upd_info)                   \
567       SymX(stg_ap_4_upd_info)                   \
568       SymX(stg_ap_5_upd_info)                   \
569       SymX(stg_ap_6_upd_info)                   \
570       SymX(stg_ap_7_upd_info)                   \
571       SymX(stg_exit)                            \
572       SymX(stg_sel_0_upd_info)                  \
573       SymX(stg_sel_10_upd_info)                 \
574       SymX(stg_sel_11_upd_info)                 \
575       SymX(stg_sel_12_upd_info)                 \
576       SymX(stg_sel_13_upd_info)                 \
577       SymX(stg_sel_14_upd_info)                 \
578       SymX(stg_sel_15_upd_info)                 \
579       SymX(stg_sel_1_upd_info)                  \
580       SymX(stg_sel_2_upd_info)                  \
581       SymX(stg_sel_3_upd_info)                  \
582       SymX(stg_sel_4_upd_info)                  \
583       SymX(stg_sel_5_upd_info)                  \
584       SymX(stg_sel_6_upd_info)                  \
585       SymX(stg_sel_7_upd_info)                  \
586       SymX(stg_sel_8_upd_info)                  \
587       SymX(stg_sel_9_upd_info)                  \
588       SymX(stg_upd_frame_info)                  \
589       SymX(suspendThread)                       \
590       SymX(takeMVarzh_fast)                     \
591       SymX(timesIntegerzh_fast)                 \
592       SymX(tryPutMVarzh_fast)                   \
593       SymX(tryTakeMVarzh_fast)                  \
594       SymX(unblockAsyncExceptionszh_fast)       \
595       SymX(unloadObj)                           \
596       SymX(unsafeThawArrayzh_fast)              \
597       SymX(waitReadzh_fast)                     \
598       SymX(waitWritezh_fast)                    \
599       SymX(word2Integerzh_fast)                 \
600       SymX(writeTVarzh_fast)                    \
601       SymX(xorIntegerzh_fast)                   \
602       SymX(yieldzh_fast)                        \
603       RTS_USER_SIGNALS_SYMBOLS
604
605 #ifdef SUPPORT_LONG_LONGS
606 #define RTS_LONG_LONG_SYMS                      \
607       SymX(int64ToIntegerzh_fast)               \
608       SymX(word64ToIntegerzh_fast)
609 #else
610 #define RTS_LONG_LONG_SYMS /* nothing */
611 #endif
612
613 // 64-bit support functions in libgcc.a
614 #if defined(__GNUC__) && SIZEOF_VOID_P <= 4
615 #define RTS_LIBGCC_SYMBOLS                      \
616       Sym(__divdi3)                             \
617       Sym(__udivdi3)                            \
618       Sym(__moddi3)                             \
619       Sym(__umoddi3)                            \
620       Sym(__muldi3)                             \
621       Sym(__ashldi3)                            \
622       Sym(__ashrdi3)                            \
623       Sym(__lshrdi3)                            \
624       Sym(__eprintf)
625 #elif defined(ia64_HOST_ARCH)
626 #define RTS_LIBGCC_SYMBOLS                      \
627       Sym(__divdi3)                             \
628       Sym(__udivdi3)                            \
629       Sym(__moddi3)                             \
630       Sym(__umoddi3)                            \
631       Sym(__divsf3)                             \
632       Sym(__divdf3)
633 #else
634 #define RTS_LIBGCC_SYMBOLS
635 #endif
636
637 #ifdef darwin_HOST_OS
638       // Symbols that don't have a leading underscore
639       // on Mac OS X. They have to receive special treatment,
640       // see machoInitSymbolsWithoutUnderscore()
641 #define RTS_MACHO_NOUNDERLINE_SYMBOLS           \
642       Sym(saveFP)                               \
643       Sym(restFP)
644 #endif
645
646 /* entirely bogus claims about types of these symbols */
647 #define Sym(vvv)  extern void vvv(void);
648 #define SymX(vvv) /**/
649 #define SymX_redirect(vvv,xxx) /**/
650 RTS_SYMBOLS
651 RTS_RET_SYMBOLS
652 RTS_LONG_LONG_SYMS
653 RTS_POSIX_ONLY_SYMBOLS
654 RTS_MINGW_ONLY_SYMBOLS
655 RTS_CYGWIN_ONLY_SYMBOLS
656 RTS_LIBGCC_SYMBOLS
657 #undef Sym
658 #undef SymX
659 #undef SymX_redirect
660
661 #ifdef LEADING_UNDERSCORE
662 #define MAYBE_LEADING_UNDERSCORE_STR(s) ("_" s)
663 #else
664 #define MAYBE_LEADING_UNDERSCORE_STR(s) (s)
665 #endif
666
667 #define Sym(vvv) { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
668                     (void*)(&(vvv)) },
669 #define SymX(vvv) Sym(vvv)
670
671 // SymX_redirect allows us to redirect references to one symbol to
672 // another symbol.  See newCAF/newDynCAF for an example.
673 #define SymX_redirect(vvv,xxx) \
674     { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
675       (void*)(&(xxx)) },
676
677 static RtsSymbolVal rtsSyms[] = {
678       RTS_SYMBOLS
679       RTS_RET_SYMBOLS
680       RTS_LONG_LONG_SYMS
681       RTS_POSIX_ONLY_SYMBOLS
682       RTS_MINGW_ONLY_SYMBOLS
683       RTS_CYGWIN_ONLY_SYMBOLS
684       RTS_LIBGCC_SYMBOLS
685       { 0, 0 } /* sentinel */
686 };
687
688 /* -----------------------------------------------------------------------------
689  * Insert symbols into hash tables, checking for duplicates.
690  */
691 static void ghciInsertStrHashTable ( char* obj_name,
692                                      HashTable *table,
693                                      char* key,
694                                      void *data
695                                    )
696 {
697    if (lookupHashTable(table, (StgWord)key) == NULL)
698    {
699       insertStrHashTable(table, (StgWord)key, data);
700       return;
701    }
702    debugBelch(
703       "\n\n"
704       "GHCi runtime linker: fatal error: I found a duplicate definition for symbol\n"
705       "   %s\n"
706       "whilst processing object file\n"
707       "   %s\n"
708       "This could be caused by:\n"
709       "   * Loading two different object files which export the same symbol\n"
710       "   * Specifying the same object file twice on the GHCi command line\n"
711       "   * An incorrect `package.conf' entry, causing some object to be\n"
712       "     loaded twice.\n"
713       "GHCi cannot safely continue in this situation.  Exiting now.  Sorry.\n"
714       "\n",
715       (char*)key,
716       obj_name
717    );
718    exit(1);
719 }
720
721
722 /* -----------------------------------------------------------------------------
723  * initialize the object linker
724  */
725
726
727 static int linker_init_done = 0 ;
728
729 #if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
730 static void *dl_prog_handle;
731 #endif
732
733 /* dlopen(NULL,..) doesn't work so we grab libc explicitly */
734 #if defined(openbsd_HOST_OS)
735 static void *dl_libc_handle;
736 #endif
737
738 void
739 initLinker( void )
740 {
741     RtsSymbolVal *sym;
742
743     /* Make initLinker idempotent, so we can call it
744        before evey relevant operation; that means we
745        don't need to initialise the linker separately */
746     if (linker_init_done == 1) { return; } else {
747       linker_init_done = 1;
748     }
749
750     symhash = allocStrHashTable();
751
752     /* populate the symbol table with stuff from the RTS */
753     for (sym = rtsSyms; sym->lbl != NULL; sym++) {
754         ghciInsertStrHashTable("(GHCi built-in symbols)",
755                                symhash, sym->lbl, sym->addr);
756     }
757 #   if defined(OBJFORMAT_MACHO)
758     machoInitSymbolsWithoutUnderscore();
759 #   endif
760
761 #   if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
762 #   if defined(RTLD_DEFAULT)
763     dl_prog_handle = RTLD_DEFAULT;
764 #   else
765     dl_prog_handle = dlopen(NULL, RTLD_LAZY);
766 #   if defined(openbsd_HOST_OS)
767     dl_libc_handle = dlopen("libc.so", RTLD_LAZY);
768 #   endif
769 #   endif /* RTLD_DEFAULT */
770 #   endif
771 }
772
773 /* -----------------------------------------------------------------------------
774  *                  Loading DLL or .so dynamic libraries
775  * -----------------------------------------------------------------------------
776  *
777  * Add a DLL from which symbols may be found.  In the ELF case, just
778  * do RTLD_GLOBAL-style add, so no further messing around needs to
779  * happen in order that symbols in the loaded .so are findable --
780  * lookupSymbol() will subsequently see them by dlsym on the program's
781  * dl-handle.  Returns NULL if success, otherwise ptr to an err msg.
782  *
783  * In the PEi386 case, open the DLLs and put handles to them in a
784  * linked list.  When looking for a symbol, try all handles in the
785  * list.  This means that we need to load even DLLs that are guaranteed
786  * to be in the ghc.exe image already, just so we can get a handle
787  * to give to loadSymbol, so that we can find the symbols.  For such
788  * libraries, the LoadLibrary call should be a no-op except for returning
789  * the handle.
790  *
791  */
792
793 #if defined(OBJFORMAT_PEi386)
794 /* A record for storing handles into DLLs. */
795
796 typedef
797    struct _OpenedDLL {
798       char*              name;
799       struct _OpenedDLL* next;
800       HINSTANCE instance;
801    }
802    OpenedDLL;
803
804 /* A list thereof. */
805 static OpenedDLL* opened_dlls = NULL;
806 #endif
807
808 char *
809 addDLL( char *dll_name )
810 {
811 #  if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
812    /* ------------------- ELF DLL loader ------------------- */
813    void *hdl;
814    char *errmsg;
815
816    initLinker();
817
818    hdl= dlopen(dll_name, RTLD_NOW | RTLD_GLOBAL);
819
820    if (hdl == NULL) {
821       /* dlopen failed; return a ptr to the error msg. */
822       errmsg = dlerror();
823       if (errmsg == NULL) errmsg = "addDLL: unknown error";
824       return errmsg;
825    } else {
826       return NULL;
827    }
828    /*NOTREACHED*/
829
830 #  elif defined(OBJFORMAT_PEi386)
831    /* ------------------- Win32 DLL loader ------------------- */
832
833    char*      buf;
834    OpenedDLL* o_dll;
835    HINSTANCE  instance;
836
837    initLinker();
838
839    /* debugBelch("\naddDLL; dll_name = `%s'\n", dll_name); */
840
841    /* See if we've already got it, and ignore if so. */
842    for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
843       if (0 == strcmp(o_dll->name, dll_name))
844          return NULL;
845    }
846
847    /* The file name has no suffix (yet) so that we can try
848       both foo.dll and foo.drv
849
850       The documentation for LoadLibrary says:
851         If no file name extension is specified in the lpFileName
852         parameter, the default library extension .dll is
853         appended. However, the file name string can include a trailing
854         point character (.) to indicate that the module name has no
855         extension. */
856
857    buf = stgMallocBytes(strlen(dll_name) + 10, "addDLL");
858    sprintf(buf, "%s.DLL", dll_name);
859    instance = LoadLibrary(buf);
860    if (instance == NULL) {
861          sprintf(buf, "%s.DRV", dll_name);      // KAA: allow loading of drivers (like winspool.drv)
862          instance = LoadLibrary(buf);
863          if (instance == NULL) {
864                 stgFree(buf);
865
866             /* LoadLibrary failed; return a ptr to the error msg. */
867             return "addDLL: unknown error";
868          }
869    }
870    stgFree(buf);
871
872    /* Add this DLL to the list of DLLs in which to search for symbols. */
873    o_dll = stgMallocBytes( sizeof(OpenedDLL), "addDLL" );
874    o_dll->name     = stgMallocBytes(1+strlen(dll_name), "addDLL");
875    strcpy(o_dll->name, dll_name);
876    o_dll->instance = instance;
877    o_dll->next     = opened_dlls;
878    opened_dlls     = o_dll;
879
880    return NULL;
881 #  else
882    barf("addDLL: not implemented on this platform");
883 #  endif
884 }
885
886 /* -----------------------------------------------------------------------------
887  * lookup a symbol in the hash table
888  */
889 void *
890 lookupSymbol( char *lbl )
891 {
892     void *val;
893     initLinker() ;
894     ASSERT(symhash != NULL);
895     val = lookupStrHashTable(symhash, lbl);
896
897     if (val == NULL) {
898 #       if defined(OBJFORMAT_ELF)
899 #       if defined(openbsd_HOST_OS)
900         val = dlsym(dl_prog_handle, lbl);
901         return (val != NULL) ? val : dlsym(dl_libc_handle,lbl);
902 #       else /* not openbsd */
903         return dlsym(dl_prog_handle, lbl);
904 #       endif
905 #       elif defined(OBJFORMAT_MACHO)
906         if(NSIsSymbolNameDefined(lbl)) {
907             NSSymbol symbol = NSLookupAndBindSymbol(lbl);
908             return NSAddressOfSymbol(symbol);
909         } else {
910             return NULL;
911         }
912 #       elif defined(OBJFORMAT_PEi386)
913         OpenedDLL* o_dll;
914         void* sym;
915         for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
916           /* debugBelch("look in %s for %s\n", o_dll->name, lbl); */
917            if (lbl[0] == '_') {
918               /* HACK: if the name has an initial underscore, try stripping
919                  it off & look that up first. I've yet to verify whether there's
920                  a Rule that governs whether an initial '_' *should always* be
921                  stripped off when mapping from import lib name to the DLL name.
922               */
923               sym = GetProcAddress(o_dll->instance, (lbl+1));
924               if (sym != NULL) {
925                 /*debugBelch("found %s in %s\n", lbl+1,o_dll->name);*/
926                 return sym;
927               }
928            }
929            sym = GetProcAddress(o_dll->instance, lbl);
930            if (sym != NULL) {
931              /*debugBelch("found %s in %s\n", lbl,o_dll->name);*/
932              return sym;
933            }
934         }
935         return NULL;
936 #       else
937         ASSERT(2+2 == 5);
938         return NULL;
939 #       endif
940     } else {
941         return val;
942     }
943 }
944
945 static
946 __attribute((unused))
947 void *
948 lookupLocalSymbol( ObjectCode* oc, char *lbl )
949 {
950     void *val;
951     initLinker() ;
952     val = lookupStrHashTable(oc->lochash, lbl);
953
954     if (val == NULL) {
955         return NULL;
956     } else {
957         return val;
958     }
959 }
960
961
962 /* -----------------------------------------------------------------------------
963  * Debugging aid: look in GHCi's object symbol tables for symbols
964  * within DELTA bytes of the specified address, and show their names.
965  */
966 #ifdef DEBUG
967 void ghci_enquire ( char* addr );
968
969 void ghci_enquire ( char* addr )
970 {
971    int   i;
972    char* sym;
973    char* a;
974    const int DELTA = 64;
975    ObjectCode* oc;
976
977    initLinker();
978
979    for (oc = objects; oc; oc = oc->next) {
980       for (i = 0; i < oc->n_symbols; i++) {
981          sym = oc->symbols[i];
982          if (sym == NULL) continue;
983          // debugBelch("enquire %p %p\n", sym, oc->lochash);
984          a = NULL;
985          if (oc->lochash != NULL) {
986             a = lookupStrHashTable(oc->lochash, sym);
987          }
988          if (a == NULL) {
989             a = lookupStrHashTable(symhash, sym);
990          }
991          if (a == NULL) {
992              // debugBelch("ghci_enquire: can't find %s\n", sym);
993          }
994          else if (addr-DELTA <= a && a <= addr+DELTA) {
995             debugBelch("%p + %3d  ==  `%s'\n", addr, a - addr, sym);
996          }
997       }
998    }
999 }
1000 #endif
1001
1002 #ifdef ia64_HOST_ARCH
1003 static unsigned int PLTSize(void);
1004 #endif
1005
1006 /* -----------------------------------------------------------------------------
1007  * Load an obj (populate the global symbol table, but don't resolve yet)
1008  *
1009  * Returns: 1 if ok, 0 on error.
1010  */
1011 HsInt
1012 loadObj( char *path )
1013 {
1014    ObjectCode* oc;
1015    struct stat st;
1016    int r, n;
1017 #ifdef USE_MMAP
1018    int fd, pagesize;
1019    void *map_addr = NULL;
1020 #else
1021    FILE *f;
1022 #endif
1023
1024    initLinker();
1025
1026    /* debugBelch("loadObj %s\n", path ); */
1027
1028    /* Check that we haven't already loaded this object. 
1029       Ignore requests to load multiple times */
1030    {
1031        ObjectCode *o;
1032        int is_dup = 0;
1033        for (o = objects; o; o = o->next) {
1034           if (0 == strcmp(o->fileName, path)) {
1035              is_dup = 1;
1036              break; /* don't need to search further */
1037           }
1038        }
1039        if (is_dup) {
1040           IF_DEBUG(linker, debugBelch(
1041             "GHCi runtime linker: warning: looks like you're trying to load the\n"
1042             "same object file twice:\n"
1043             "   %s\n"
1044             "GHCi will ignore this, but be warned.\n"
1045             , path));
1046           return 1; /* success */
1047        }
1048    }
1049
1050    oc = stgMallocBytes(sizeof(ObjectCode), "loadObj(oc)");
1051
1052 #  if defined(OBJFORMAT_ELF)
1053    oc->formatName = "ELF";
1054 #  elif defined(OBJFORMAT_PEi386)
1055    oc->formatName = "PEi386";
1056 #  elif defined(OBJFORMAT_MACHO)
1057    oc->formatName = "Mach-O";
1058 #  else
1059    stgFree(oc);
1060    barf("loadObj: not implemented on this platform");
1061 #  endif
1062
1063    r = stat(path, &st);
1064    if (r == -1) { return 0; }
1065
1066    /* sigh, strdup() isn't a POSIX function, so do it the long way */
1067    oc->fileName = stgMallocBytes( strlen(path)+1, "loadObj" );
1068    strcpy(oc->fileName, path);
1069
1070    oc->fileSize          = st.st_size;
1071    oc->symbols           = NULL;
1072    oc->sections          = NULL;
1073    oc->lochash           = allocStrHashTable();
1074    oc->proddables        = NULL;
1075
1076    /* chain it onto the list of objects */
1077    oc->next              = objects;
1078    objects               = oc;
1079
1080 #ifdef USE_MMAP
1081 #define ROUND_UP(x,size) ((x + size - 1) & ~(size - 1))
1082
1083    /* On many architectures malloc'd memory isn't executable, so we need to use mmap. */
1084
1085 #if defined(openbsd_HOST_OS)
1086    fd = open(path, O_RDONLY, S_IRUSR);
1087 #else
1088    fd = open(path, O_RDONLY);
1089 #endif
1090    if (fd == -1)
1091       barf("loadObj: can't open `%s'", path);
1092
1093    pagesize = getpagesize();
1094
1095 #ifdef ia64_HOST_ARCH
1096    /* The PLT needs to be right before the object */
1097    n = ROUND_UP(PLTSize(), pagesize);
1098    oc->plt = mmap(NULL, n, PROT_EXEC|PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
1099    if (oc->plt == MAP_FAILED)
1100       barf("loadObj: can't allocate PLT");
1101
1102    oc->pltIndex = 0;
1103    map_addr = oc->plt + n;
1104 #endif
1105
1106    n = ROUND_UP(oc->fileSize, pagesize);
1107
1108    /* Link objects into the lower 2Gb on x86_64.  GHC assumes the
1109     * small memory model on this architecture (see gcc docs,
1110     * -mcmodel=small).
1111     */
1112 #ifdef x86_64_HOST_ARCH
1113 #define EXTRA_MAP_FLAGS MAP_32BIT
1114 #else
1115 #define EXTRA_MAP_FLAGS 0
1116 #endif
1117
1118    oc->image = mmap(map_addr, n, PROT_EXEC|PROT_READ|PROT_WRITE, 
1119                     MAP_PRIVATE|EXTRA_MAP_FLAGS, fd, 0);
1120    if (oc->image == MAP_FAILED)
1121       barf("loadObj: can't map `%s'", path);
1122
1123    close(fd);
1124
1125 #else /* !USE_MMAP */
1126
1127    oc->image = stgMallocBytes(oc->fileSize, "loadObj(image)");
1128
1129    /* load the image into memory */
1130    f = fopen(path, "rb");
1131    if (!f)
1132        barf("loadObj: can't read `%s'", path);
1133
1134    n = fread ( oc->image, 1, oc->fileSize, f );
1135    if (n != oc->fileSize)
1136       barf("loadObj: error whilst reading `%s'", path);
1137
1138    fclose(f);
1139
1140 #endif /* USE_MMAP */
1141
1142 #  if defined(OBJFORMAT_MACHO)
1143    r = ocAllocateJumpIslands_MachO ( oc );
1144    if (!r) { return r; }
1145 #  elif defined(OBJFORMAT_ELF) && defined(powerpc_HOST_ARCH)
1146    r = ocAllocateJumpIslands_ELF ( oc );
1147    if (!r) { return r; }
1148 #endif
1149
1150    /* verify the in-memory image */
1151 #  if defined(OBJFORMAT_ELF)
1152    r = ocVerifyImage_ELF ( oc );
1153 #  elif defined(OBJFORMAT_PEi386)
1154    r = ocVerifyImage_PEi386 ( oc );
1155 #  elif defined(OBJFORMAT_MACHO)
1156    r = ocVerifyImage_MachO ( oc );
1157 #  else
1158    barf("loadObj: no verify method");
1159 #  endif
1160    if (!r) { return r; }
1161
1162    /* build the symbol list for this image */
1163 #  if defined(OBJFORMAT_ELF)
1164    r = ocGetNames_ELF ( oc );
1165 #  elif defined(OBJFORMAT_PEi386)
1166    r = ocGetNames_PEi386 ( oc );
1167 #  elif defined(OBJFORMAT_MACHO)
1168    r = ocGetNames_MachO ( oc );
1169 #  else
1170    barf("loadObj: no getNames method");
1171 #  endif
1172    if (!r) { return r; }
1173
1174    /* loaded, but not resolved yet */
1175    oc->status = OBJECT_LOADED;
1176
1177    return 1;
1178 }
1179
1180 /* -----------------------------------------------------------------------------
1181  * resolve all the currently unlinked objects in memory
1182  *
1183  * Returns: 1 if ok, 0 on error.
1184  */
1185 HsInt
1186 resolveObjs( void )
1187 {
1188     ObjectCode *oc;
1189     int r;
1190
1191     initLinker();
1192
1193     for (oc = objects; oc; oc = oc->next) {
1194         if (oc->status != OBJECT_RESOLVED) {
1195 #           if defined(OBJFORMAT_ELF)
1196             r = ocResolve_ELF ( oc );
1197 #           elif defined(OBJFORMAT_PEi386)
1198             r = ocResolve_PEi386 ( oc );
1199 #           elif defined(OBJFORMAT_MACHO)
1200             r = ocResolve_MachO ( oc );
1201 #           else
1202             barf("resolveObjs: not implemented on this platform");
1203 #           endif
1204             if (!r) { return r; }
1205             oc->status = OBJECT_RESOLVED;
1206         }
1207     }
1208     return 1;
1209 }
1210
1211 /* -----------------------------------------------------------------------------
1212  * delete an object from the pool
1213  */
1214 HsInt
1215 unloadObj( char *path )
1216 {
1217     ObjectCode *oc, *prev;
1218
1219     ASSERT(symhash != NULL);
1220     ASSERT(objects != NULL);
1221
1222     initLinker();
1223
1224     prev = NULL;
1225     for (oc = objects; oc; prev = oc, oc = oc->next) {
1226         if (!strcmp(oc->fileName,path)) {
1227
1228             /* Remove all the mappings for the symbols within this
1229              * object..
1230              */
1231             {
1232                 int i;
1233                 for (i = 0; i < oc->n_symbols; i++) {
1234                    if (oc->symbols[i] != NULL) {
1235                        removeStrHashTable(symhash, oc->symbols[i], NULL);
1236                    }
1237                 }
1238             }
1239
1240             if (prev == NULL) {
1241                 objects = oc->next;
1242             } else {
1243                 prev->next = oc->next;
1244             }
1245
1246             /* We're going to leave this in place, in case there are
1247                any pointers from the heap into it: */
1248             /* stgFree(oc->image); */
1249             stgFree(oc->fileName);
1250             stgFree(oc->symbols);
1251             stgFree(oc->sections);
1252             /* The local hash table should have been freed at the end
1253                of the ocResolve_ call on it. */
1254             ASSERT(oc->lochash == NULL);
1255             stgFree(oc);
1256             return 1;
1257         }
1258     }
1259
1260     errorBelch("unloadObj: can't find `%s' to unload", path);
1261     return 0;
1262 }
1263
1264 /* -----------------------------------------------------------------------------
1265  * Sanity checking.  For each ObjectCode, maintain a list of address ranges
1266  * which may be prodded during relocation, and abort if we try and write
1267  * outside any of these.
1268  */
1269 static void addProddableBlock ( ObjectCode* oc, void* start, int size )
1270 {
1271    ProddableBlock* pb
1272       = stgMallocBytes(sizeof(ProddableBlock), "addProddableBlock");
1273    /* debugBelch("aPB %p %p %d\n", oc, start, size); */
1274    ASSERT(size > 0);
1275    pb->start      = start;
1276    pb->size       = size;
1277    pb->next       = oc->proddables;
1278    oc->proddables = pb;
1279 }
1280
1281 static void checkProddableBlock ( ObjectCode* oc, void* addr )
1282 {
1283    ProddableBlock* pb;
1284    for (pb = oc->proddables; pb != NULL; pb = pb->next) {
1285       char* s = (char*)(pb->start);
1286       char* e = s + pb->size - 1;
1287       char* a = (char*)addr;
1288       /* Assumes that the biggest fixup involves a 4-byte write.  This
1289          probably needs to be changed to 8 (ie, +7) on 64-bit
1290          plats. */
1291       if (a >= s && (a+3) <= e) return;
1292    }
1293    barf("checkProddableBlock: invalid fixup in runtime linker");
1294 }
1295
1296 /* -----------------------------------------------------------------------------
1297  * Section management.
1298  */
1299 static void addSection ( ObjectCode* oc, SectionKind kind,
1300                          void* start, void* end )
1301 {
1302    Section* s   = stgMallocBytes(sizeof(Section), "addSection");
1303    s->start     = start;
1304    s->end       = end;
1305    s->kind      = kind;
1306    s->next      = oc->sections;
1307    oc->sections = s;
1308    /*
1309    debugBelch("addSection: %p-%p (size %d), kind %d\n",
1310                    start, ((char*)end)-1, end - start + 1, kind );
1311    */
1312 }
1313
1314
1315 /* --------------------------------------------------------------------------
1316  * PowerPC specifics (jump islands)
1317  * ------------------------------------------------------------------------*/
1318
1319 #if defined(powerpc_HOST_ARCH)
1320
1321 /*
1322   ocAllocateJumpIslands
1323   
1324   Allocate additional space at the end of the object file image to make room
1325   for jump islands.
1326   
1327   PowerPC relative branch instructions have a 24 bit displacement field.
1328   As PPC code is always 4-byte-aligned, this yields a +-32MB range.
1329   If a particular imported symbol is outside this range, we have to redirect
1330   the jump to a short piece of new code that just loads the 32bit absolute
1331   address and jumps there.
1332   This function just allocates space for one 16 byte ppcJumpIsland for every
1333   undefined symbol in the object file. The code for the islands is filled in by
1334   makeJumpIsland below.
1335 */
1336
1337 static int ocAllocateJumpIslands( ObjectCode* oc, int count, int first )
1338 {
1339 #ifdef USE_MMAP
1340   int pagesize, n, m;
1341 #endif
1342   int aligned;
1343
1344   if( count > 0 )
1345   {
1346     // round up to the nearest 4
1347     aligned = (oc->fileSize + 3) & ~3;
1348
1349 #ifdef USE_MMAP
1350     #ifndef linux_HOST_OS /* mremap is a linux extension */
1351         #error ocAllocateJumpIslands doesnt want USE_MMAP to be defined
1352     #endif
1353
1354     pagesize = getpagesize();
1355     n = ROUND_UP( oc->fileSize, pagesize );
1356     m = ROUND_UP( aligned + sizeof (ppcJumpIsland) * count, pagesize );
1357
1358     /* The effect of this mremap() call is only the ensure that we have
1359      * a sufficient number of virtually contiguous pages.  As returned from
1360      * mremap, the pages past the end of the file are not backed.  We give
1361      * them a backing by using MAP_FIXED to map in anonymous pages.
1362      */
1363     if( (oc->image = mremap( oc->image, n, m, MREMAP_MAYMOVE )) == MAP_FAILED )
1364     {
1365       errorBelch( "Unable to mremap for Jump Islands\n" );
1366       return 0;
1367     }
1368
1369     if( mmap( oc->image + n, m - n, PROT_READ | PROT_WRITE | PROT_EXEC,
1370               MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, 0, 0 ) == MAP_FAILED )
1371     {
1372       errorBelch( "Unable to mmap( MAP_FIXED ) for Jump Islands\n" );
1373       return 0;
1374     }
1375
1376 #else
1377     oc->image = stgReallocBytes( oc->image,
1378                                  aligned + sizeof (ppcJumpIsland) * count,
1379                                  "ocAllocateJumpIslands" );
1380 #endif /* USE_MMAP */
1381
1382     oc->jump_islands = (ppcJumpIsland *) (oc->image + aligned);
1383     memset( oc->jump_islands, 0, sizeof (ppcJumpIsland) * count );
1384   }
1385   else
1386     oc->jump_islands = NULL;
1387
1388   oc->island_start_symbol = first;
1389   oc->n_islands = count;
1390
1391   return 1;
1392 }
1393
1394 static unsigned long makeJumpIsland( ObjectCode* oc,
1395                                      unsigned long symbolNumber,
1396                                      unsigned long target )
1397 {
1398   ppcJumpIsland *island;
1399
1400   if( symbolNumber < oc->island_start_symbol ||
1401       symbolNumber - oc->island_start_symbol > oc->n_islands)
1402     return 0;
1403
1404   island = &oc->jump_islands[symbolNumber - oc->island_start_symbol];
1405
1406   // lis r12, hi16(target)
1407   island->lis_r12     = 0x3d80;
1408   island->hi_addr     = target >> 16;
1409
1410   // ori r12, r12, lo16(target)
1411   island->ori_r12_r12 = 0x618c;
1412   island->lo_addr     = target & 0xffff;
1413
1414   // mtctr r12
1415   island->mtctr_r12   = 0x7d8903a6;
1416
1417   // bctr
1418   island->bctr        = 0x4e800420;
1419     
1420   return (unsigned long) island;
1421 }
1422
1423 /*
1424    ocFlushInstructionCache
1425
1426    Flush the data & instruction caches.
1427    Because the PPC has split data/instruction caches, we have to
1428    do that whenever we modify code at runtime.
1429  */
1430
1431 static void ocFlushInstructionCache( ObjectCode *oc )
1432 {
1433     int n = (oc->fileSize + sizeof( ppcJumpIsland ) * oc->n_islands + 3) / 4;
1434     unsigned long *p = (unsigned long *) oc->image;
1435
1436     while( n-- )
1437     {
1438         __asm__ volatile ( "dcbf 0,%0\n\t"
1439                            "sync\n\t"
1440                            "icbi 0,%0"
1441                            :
1442                            : "r" (p)
1443                          );
1444         p++;
1445     }
1446     __asm__ volatile ( "sync\n\t"
1447                        "isync"
1448                      );
1449 }
1450 #endif
1451
1452 /* --------------------------------------------------------------------------
1453  * PEi386 specifics (Win32 targets)
1454  * ------------------------------------------------------------------------*/
1455
1456 /* The information for this linker comes from
1457       Microsoft Portable Executable
1458       and Common Object File Format Specification
1459       revision 5.1 January 1998
1460    which SimonM says comes from the MS Developer Network CDs.
1461
1462    It can be found there (on older CDs), but can also be found
1463    online at:
1464
1465       http://www.microsoft.com/hwdev/hardware/PECOFF.asp
1466
1467    (this is Rev 6.0 from February 1999).
1468
1469    Things move, so if that fails, try searching for it via
1470
1471       http://www.google.com/search?q=PE+COFF+specification
1472
1473    The ultimate reference for the PE format is the Winnt.h
1474    header file that comes with the Platform SDKs; as always,
1475    implementations will drift wrt their documentation.
1476
1477    A good background article on the PE format is Matt Pietrek's
1478    March 1994 article in Microsoft System Journal (MSJ)
1479    (Vol.9, No. 3): "Peering Inside the PE: A Tour of the
1480    Win32 Portable Executable File Format." The info in there
1481    has recently been updated in a two part article in
1482    MSDN magazine, issues Feb and March 2002,
1483    "Inside Windows: An In-Depth Look into the Win32 Portable
1484    Executable File Format"
1485
1486    John Levine's book "Linkers and Loaders" contains useful
1487    info on PE too.
1488 */
1489
1490
1491 #if defined(OBJFORMAT_PEi386)
1492
1493
1494
1495 typedef unsigned char  UChar;
1496 typedef unsigned short UInt16;
1497 typedef unsigned int   UInt32;
1498 typedef          int   Int32;
1499
1500
1501 typedef
1502    struct {
1503       UInt16 Machine;
1504       UInt16 NumberOfSections;
1505       UInt32 TimeDateStamp;
1506       UInt32 PointerToSymbolTable;
1507       UInt32 NumberOfSymbols;
1508       UInt16 SizeOfOptionalHeader;
1509       UInt16 Characteristics;
1510    }
1511    COFF_header;
1512
1513 #define sizeof_COFF_header 20
1514
1515
1516 typedef
1517    struct {
1518       UChar  Name[8];
1519       UInt32 VirtualSize;
1520       UInt32 VirtualAddress;
1521       UInt32 SizeOfRawData;
1522       UInt32 PointerToRawData;
1523       UInt32 PointerToRelocations;
1524       UInt32 PointerToLinenumbers;
1525       UInt16 NumberOfRelocations;
1526       UInt16 NumberOfLineNumbers;
1527       UInt32 Characteristics;
1528    }
1529    COFF_section;
1530
1531 #define sizeof_COFF_section 40
1532
1533
1534 typedef
1535    struct {
1536       UChar  Name[8];
1537       UInt32 Value;
1538       UInt16 SectionNumber;
1539       UInt16 Type;
1540       UChar  StorageClass;
1541       UChar  NumberOfAuxSymbols;
1542    }
1543    COFF_symbol;
1544
1545 #define sizeof_COFF_symbol 18
1546
1547
1548 typedef
1549    struct {
1550       UInt32 VirtualAddress;
1551       UInt32 SymbolTableIndex;
1552       UInt16 Type;
1553    }
1554    COFF_reloc;
1555
1556 #define sizeof_COFF_reloc 10
1557
1558
1559 /* From PE spec doc, section 3.3.2 */
1560 /* Note use of MYIMAGE_* since IMAGE_* are already defined in
1561    windows.h -- for the same purpose, but I want to know what I'm
1562    getting, here. */
1563 #define MYIMAGE_FILE_RELOCS_STRIPPED     0x0001
1564 #define MYIMAGE_FILE_EXECUTABLE_IMAGE    0x0002
1565 #define MYIMAGE_FILE_DLL                 0x2000
1566 #define MYIMAGE_FILE_SYSTEM              0x1000
1567 #define MYIMAGE_FILE_BYTES_REVERSED_HI   0x8000
1568 #define MYIMAGE_FILE_BYTES_REVERSED_LO   0x0080
1569 #define MYIMAGE_FILE_32BIT_MACHINE       0x0100
1570
1571 /* From PE spec doc, section 5.4.2 and 5.4.4 */
1572 #define MYIMAGE_SYM_CLASS_EXTERNAL       2
1573 #define MYIMAGE_SYM_CLASS_STATIC         3
1574 #define MYIMAGE_SYM_UNDEFINED            0
1575
1576 /* From PE spec doc, section 4.1 */
1577 #define MYIMAGE_SCN_CNT_CODE             0x00000020
1578 #define MYIMAGE_SCN_CNT_INITIALIZED_DATA 0x00000040
1579 #define MYIMAGE_SCN_LNK_NRELOC_OVFL      0x01000000
1580
1581 /* From PE spec doc, section 5.2.1 */
1582 #define MYIMAGE_REL_I386_DIR32           0x0006
1583 #define MYIMAGE_REL_I386_REL32           0x0014
1584
1585
1586 /* We use myindex to calculate array addresses, rather than
1587    simply doing the normal subscript thing.  That's because
1588    some of the above structs have sizes which are not
1589    a whole number of words.  GCC rounds their sizes up to a
1590    whole number of words, which means that the address calcs
1591    arising from using normal C indexing or pointer arithmetic
1592    are just plain wrong.  Sigh.
1593 */
1594 static UChar *
1595 myindex ( int scale, void* base, int index )
1596 {
1597    return
1598       ((UChar*)base) + scale * index;
1599 }
1600
1601
1602 static void
1603 printName ( UChar* name, UChar* strtab )
1604 {
1605    if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1606       UInt32 strtab_offset = * (UInt32*)(name+4);
1607       debugBelch("%s", strtab + strtab_offset );
1608    } else {
1609       int i;
1610       for (i = 0; i < 8; i++) {
1611          if (name[i] == 0) break;
1612          debugBelch("%c", name[i] );
1613       }
1614    }
1615 }
1616
1617
1618 static void
1619 copyName ( UChar* name, UChar* strtab, UChar* dst, int dstSize )
1620 {
1621    if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1622       UInt32 strtab_offset = * (UInt32*)(name+4);
1623       strncpy ( dst, strtab+strtab_offset, dstSize );
1624       dst[dstSize-1] = 0;
1625    } else {
1626       int i = 0;
1627       while (1) {
1628          if (i >= 8) break;
1629          if (name[i] == 0) break;
1630          dst[i] = name[i];
1631          i++;
1632       }
1633       dst[i] = 0;
1634    }
1635 }
1636
1637
1638 static UChar *
1639 cstring_from_COFF_symbol_name ( UChar* name, UChar* strtab )
1640 {
1641    UChar* newstr;
1642    /* If the string is longer than 8 bytes, look in the
1643       string table for it -- this will be correctly zero terminated.
1644    */
1645    if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1646       UInt32 strtab_offset = * (UInt32*)(name+4);
1647       return ((UChar*)strtab) + strtab_offset;
1648    }
1649    /* Otherwise, if shorter than 8 bytes, return the original,
1650       which by defn is correctly terminated.
1651    */
1652    if (name[7]==0) return name;
1653    /* The annoying case: 8 bytes.  Copy into a temporary
1654       (which is never freed ...)
1655    */
1656    newstr = stgMallocBytes(9, "cstring_from_COFF_symbol_name");
1657    ASSERT(newstr);
1658    strncpy(newstr,name,8);
1659    newstr[8] = 0;
1660    return newstr;
1661 }
1662
1663
1664 /* Just compares the short names (first 8 chars) */
1665 static COFF_section *
1666 findPEi386SectionCalled ( ObjectCode* oc,  char* name )
1667 {
1668    int i;
1669    COFF_header* hdr
1670       = (COFF_header*)(oc->image);
1671    COFF_section* sectab
1672       = (COFF_section*) (
1673            ((UChar*)(oc->image))
1674            + sizeof_COFF_header + hdr->SizeOfOptionalHeader
1675         );
1676    for (i = 0; i < hdr->NumberOfSections; i++) {
1677       UChar* n1;
1678       UChar* n2;
1679       COFF_section* section_i
1680          = (COFF_section*)
1681            myindex ( sizeof_COFF_section, sectab, i );
1682       n1 = (UChar*) &(section_i->Name);
1683       n2 = name;
1684       if (n1[0]==n2[0] && n1[1]==n2[1] && n1[2]==n2[2] &&
1685           n1[3]==n2[3] && n1[4]==n2[4] && n1[5]==n2[5] &&
1686           n1[6]==n2[6] && n1[7]==n2[7])
1687          return section_i;
1688    }
1689
1690    return NULL;
1691 }
1692
1693
1694 static void
1695 zapTrailingAtSign ( UChar* sym )
1696 {
1697 #  define my_isdigit(c) ((c) >= '0' && (c) <= '9')
1698    int i, j;
1699    if (sym[0] == 0) return;
1700    i = 0;
1701    while (sym[i] != 0) i++;
1702    i--;
1703    j = i;
1704    while (j > 0 && my_isdigit(sym[j])) j--;
1705    if (j > 0 && sym[j] == '@' && j != i) sym[j] = 0;
1706 #  undef my_isdigit
1707 }
1708
1709
1710 static int
1711 ocVerifyImage_PEi386 ( ObjectCode* oc )
1712 {
1713    int i;
1714    UInt32 j, noRelocs;
1715    COFF_header*  hdr;
1716    COFF_section* sectab;
1717    COFF_symbol*  symtab;
1718    UChar*        strtab;
1719    /* debugBelch("\nLOADING %s\n", oc->fileName); */
1720    hdr = (COFF_header*)(oc->image);
1721    sectab = (COFF_section*) (
1722                ((UChar*)(oc->image))
1723                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
1724             );
1725    symtab = (COFF_symbol*) (
1726                ((UChar*)(oc->image))
1727                + hdr->PointerToSymbolTable
1728             );
1729    strtab = ((UChar*)symtab)
1730             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
1731
1732    if (hdr->Machine != 0x14c) {
1733       errorBelch("Not x86 PEi386");
1734       return 0;
1735    }
1736    if (hdr->SizeOfOptionalHeader != 0) {
1737       errorBelch("PEi386 with nonempty optional header");
1738       return 0;
1739    }
1740    if ( /* (hdr->Characteristics & MYIMAGE_FILE_RELOCS_STRIPPED) || */
1741         (hdr->Characteristics & MYIMAGE_FILE_EXECUTABLE_IMAGE) ||
1742         (hdr->Characteristics & MYIMAGE_FILE_DLL) ||
1743         (hdr->Characteristics & MYIMAGE_FILE_SYSTEM) ) {
1744       errorBelch("Not a PEi386 object file");
1745       return 0;
1746    }
1747    if ( (hdr->Characteristics & MYIMAGE_FILE_BYTES_REVERSED_HI)
1748         /* || !(hdr->Characteristics & MYIMAGE_FILE_32BIT_MACHINE) */ ) {
1749       errorBelch("Invalid PEi386 word size or endiannness: %d",
1750             (int)(hdr->Characteristics));
1751       return 0;
1752    }
1753    /* If the string table size is way crazy, this might indicate that
1754       there are more than 64k relocations, despite claims to the
1755       contrary.  Hence this test. */
1756    /* debugBelch("strtab size %d\n", * (UInt32*)strtab); */
1757 #if 0
1758    if ( (*(UInt32*)strtab) > 600000 ) {
1759       /* Note that 600k has no special significance other than being
1760          big enough to handle the almost-2MB-sized lumps that
1761          constitute HSwin32*.o. */
1762       debugBelch("PEi386 object has suspiciously large string table; > 64k relocs?");
1763       return 0;
1764    }
1765 #endif
1766
1767    /* No further verification after this point; only debug printing. */
1768    i = 0;
1769    IF_DEBUG(linker, i=1);
1770    if (i == 0) return 1;
1771
1772    debugBelch( "sectab offset = %d\n", ((UChar*)sectab) - ((UChar*)hdr) );
1773    debugBelch( "symtab offset = %d\n", ((UChar*)symtab) - ((UChar*)hdr) );
1774    debugBelch( "strtab offset = %d\n", ((UChar*)strtab) - ((UChar*)hdr) );
1775
1776    debugBelch("\n" );
1777    debugBelch( "Machine:           0x%x\n", (UInt32)(hdr->Machine) );
1778    debugBelch( "# sections:        %d\n",   (UInt32)(hdr->NumberOfSections) );
1779    debugBelch( "time/date:         0x%x\n", (UInt32)(hdr->TimeDateStamp) );
1780    debugBelch( "symtab offset:     %d\n",   (UInt32)(hdr->PointerToSymbolTable) );
1781    debugBelch( "# symbols:         %d\n",   (UInt32)(hdr->NumberOfSymbols) );
1782    debugBelch( "sz of opt hdr:     %d\n",   (UInt32)(hdr->SizeOfOptionalHeader) );
1783    debugBelch( "characteristics:   0x%x\n", (UInt32)(hdr->Characteristics) );
1784
1785    /* Print the section table. */
1786    debugBelch("\n" );
1787    for (i = 0; i < hdr->NumberOfSections; i++) {
1788       COFF_reloc* reltab;
1789       COFF_section* sectab_i
1790          = (COFF_section*)
1791            myindex ( sizeof_COFF_section, sectab, i );
1792       debugBelch(
1793                 "\n"
1794                 "section %d\n"
1795                 "     name `",
1796                 i
1797               );
1798       printName ( sectab_i->Name, strtab );
1799       debugBelch(
1800                 "'\n"
1801                 "    vsize %d\n"
1802                 "    vaddr %d\n"
1803                 "  data sz %d\n"
1804                 " data off %d\n"
1805                 "  num rel %d\n"
1806                 "  off rel %d\n"
1807                 "  ptr raw 0x%x\n",
1808                 sectab_i->VirtualSize,
1809                 sectab_i->VirtualAddress,
1810                 sectab_i->SizeOfRawData,
1811                 sectab_i->PointerToRawData,
1812                 sectab_i->NumberOfRelocations,
1813                 sectab_i->PointerToRelocations,
1814                 sectab_i->PointerToRawData
1815               );
1816       reltab = (COFF_reloc*) (
1817                   ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
1818                );
1819
1820       if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
1821         /* If the relocation field (a short) has overflowed, the
1822          * real count can be found in the first reloc entry.
1823          *
1824          * See Section 4.1 (last para) of the PE spec (rev6.0).
1825          */
1826         COFF_reloc* rel = (COFF_reloc*)
1827                            myindex ( sizeof_COFF_reloc, reltab, 0 );
1828         noRelocs = rel->VirtualAddress;
1829         j = 1;
1830       } else {
1831         noRelocs = sectab_i->NumberOfRelocations;
1832         j = 0;
1833       }
1834
1835       for (; j < noRelocs; j++) {
1836          COFF_symbol* sym;
1837          COFF_reloc* rel = (COFF_reloc*)
1838                            myindex ( sizeof_COFF_reloc, reltab, j );
1839          debugBelch(
1840                    "        type 0x%-4x   vaddr 0x%-8x   name `",
1841                    (UInt32)rel->Type,
1842                    rel->VirtualAddress );
1843          sym = (COFF_symbol*)
1844                myindex ( sizeof_COFF_symbol, symtab, rel->SymbolTableIndex );
1845          /* Hmm..mysterious looking offset - what's it for? SOF */
1846          printName ( sym->Name, strtab -10 );
1847          debugBelch("'\n" );
1848       }
1849
1850       debugBelch("\n" );
1851    }
1852    debugBelch("\n" );
1853    debugBelch("string table has size 0x%x\n", * (UInt32*)strtab );
1854    debugBelch("---START of string table---\n");
1855    for (i = 4; i < *(Int32*)strtab; i++) {
1856       if (strtab[i] == 0)
1857          debugBelch("\n"); else
1858          debugBelch("%c", strtab[i] );
1859    }
1860    debugBelch("--- END  of string table---\n");
1861
1862    debugBelch("\n" );
1863    i = 0;
1864    while (1) {
1865       COFF_symbol* symtab_i;
1866       if (i >= (Int32)(hdr->NumberOfSymbols)) break;
1867       symtab_i = (COFF_symbol*)
1868                  myindex ( sizeof_COFF_symbol, symtab, i );
1869       debugBelch(
1870                 "symbol %d\n"
1871                 "     name `",
1872                 i
1873               );
1874       printName ( symtab_i->Name, strtab );
1875       debugBelch(
1876                 "'\n"
1877                 "    value 0x%x\n"
1878                 "   1+sec# %d\n"
1879                 "     type 0x%x\n"
1880                 "   sclass 0x%x\n"
1881                 "     nAux %d\n",
1882                 symtab_i->Value,
1883                 (Int32)(symtab_i->SectionNumber),
1884                 (UInt32)symtab_i->Type,
1885                 (UInt32)symtab_i->StorageClass,
1886                 (UInt32)symtab_i->NumberOfAuxSymbols
1887               );
1888       i += symtab_i->NumberOfAuxSymbols;
1889       i++;
1890    }
1891
1892    debugBelch("\n" );
1893    return 1;
1894 }
1895
1896
1897 static int
1898 ocGetNames_PEi386 ( ObjectCode* oc )
1899 {
1900    COFF_header*  hdr;
1901    COFF_section* sectab;
1902    COFF_symbol*  symtab;
1903    UChar*        strtab;
1904
1905    UChar* sname;
1906    void*  addr;
1907    int    i;
1908
1909    hdr = (COFF_header*)(oc->image);
1910    sectab = (COFF_section*) (
1911                ((UChar*)(oc->image))
1912                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
1913             );
1914    symtab = (COFF_symbol*) (
1915                ((UChar*)(oc->image))
1916                + hdr->PointerToSymbolTable
1917             );
1918    strtab = ((UChar*)(oc->image))
1919             + hdr->PointerToSymbolTable
1920             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
1921
1922    /* Allocate space for any (local, anonymous) .bss sections. */
1923
1924    for (i = 0; i < hdr->NumberOfSections; i++) {
1925       UChar* zspace;
1926       COFF_section* sectab_i
1927          = (COFF_section*)
1928            myindex ( sizeof_COFF_section, sectab, i );
1929       if (0 != strcmp(sectab_i->Name, ".bss")) continue;
1930       if (sectab_i->VirtualSize == 0) continue;
1931       /* This is a non-empty .bss section.  Allocate zeroed space for
1932          it, and set its PointerToRawData field such that oc->image +
1933          PointerToRawData == addr_of_zeroed_space.  */
1934       zspace = stgCallocBytes(1, sectab_i->VirtualSize,
1935                               "ocGetNames_PEi386(anonymous bss)");
1936       sectab_i->PointerToRawData = ((UChar*)zspace) - ((UChar*)(oc->image));
1937       addProddableBlock(oc, zspace, sectab_i->VirtualSize);
1938       /* debugBelch("BSS anon section at 0x%x\n", zspace); */
1939    }
1940
1941    /* Copy section information into the ObjectCode. */
1942
1943    for (i = 0; i < hdr->NumberOfSections; i++) {
1944       UChar* start;
1945       UChar* end;
1946       UInt32 sz;
1947
1948       SectionKind kind
1949          = SECTIONKIND_OTHER;
1950       COFF_section* sectab_i
1951          = (COFF_section*)
1952            myindex ( sizeof_COFF_section, sectab, i );
1953       IF_DEBUG(linker, debugBelch("section name = %s\n", sectab_i->Name ));
1954
1955 #     if 0
1956       /* I'm sure this is the Right Way to do it.  However, the
1957          alternative of testing the sectab_i->Name field seems to
1958          work ok with Cygwin.
1959       */
1960       if (sectab_i->Characteristics & MYIMAGE_SCN_CNT_CODE ||
1961           sectab_i->Characteristics & MYIMAGE_SCN_CNT_INITIALIZED_DATA)
1962          kind = SECTIONKIND_CODE_OR_RODATA;
1963 #     endif
1964
1965       if (0==strcmp(".text",sectab_i->Name) ||
1966           0==strcmp(".rdata",sectab_i->Name)||
1967           0==strcmp(".rodata",sectab_i->Name))
1968          kind = SECTIONKIND_CODE_OR_RODATA;
1969       if (0==strcmp(".data",sectab_i->Name) ||
1970           0==strcmp(".bss",sectab_i->Name))
1971          kind = SECTIONKIND_RWDATA;
1972
1973       ASSERT(sectab_i->SizeOfRawData == 0 || sectab_i->VirtualSize == 0);
1974       sz = sectab_i->SizeOfRawData;
1975       if (sz < sectab_i->VirtualSize) sz = sectab_i->VirtualSize;
1976
1977       start = ((UChar*)(oc->image)) + sectab_i->PointerToRawData;
1978       end   = start + sz - 1;
1979
1980       if (kind == SECTIONKIND_OTHER
1981           /* Ignore sections called which contain stabs debugging
1982              information. */
1983           && 0 != strcmp(".stab", sectab_i->Name)
1984           && 0 != strcmp(".stabstr", sectab_i->Name)
1985           /* ignore constructor section for now */
1986           && 0 != strcmp(".ctors", sectab_i->Name)
1987          ) {
1988          errorBelch("Unknown PEi386 section name `%s' (while processing: %s)", sectab_i->Name, oc->fileName);
1989          return 0;
1990       }
1991
1992       if (kind != SECTIONKIND_OTHER && end >= start) {
1993          addSection(oc, kind, start, end);
1994          addProddableBlock(oc, start, end - start + 1);
1995       }
1996    }
1997
1998    /* Copy exported symbols into the ObjectCode. */
1999
2000    oc->n_symbols = hdr->NumberOfSymbols;
2001    oc->symbols   = stgMallocBytes(oc->n_symbols * sizeof(char*),
2002                                   "ocGetNames_PEi386(oc->symbols)");
2003    /* Call me paranoid; I don't care. */
2004    for (i = 0; i < oc->n_symbols; i++)
2005       oc->symbols[i] = NULL;
2006
2007    i = 0;
2008    while (1) {
2009       COFF_symbol* symtab_i;
2010       if (i >= (Int32)(hdr->NumberOfSymbols)) break;
2011       symtab_i = (COFF_symbol*)
2012                  myindex ( sizeof_COFF_symbol, symtab, i );
2013
2014       addr  = NULL;
2015
2016       if (symtab_i->StorageClass == MYIMAGE_SYM_CLASS_EXTERNAL
2017           && symtab_i->SectionNumber != MYIMAGE_SYM_UNDEFINED) {
2018          /* This symbol is global and defined, viz, exported */
2019          /* for MYIMAGE_SYMCLASS_EXTERNAL
2020                 && !MYIMAGE_SYM_UNDEFINED,
2021             the address of the symbol is:
2022                 address of relevant section + offset in section
2023          */
2024          COFF_section* sectabent
2025             = (COFF_section*) myindex ( sizeof_COFF_section,
2026                                         sectab,
2027                                         symtab_i->SectionNumber-1 );
2028          addr = ((UChar*)(oc->image))
2029                 + (sectabent->PointerToRawData
2030                    + symtab_i->Value);
2031       }
2032       else
2033       if (symtab_i->SectionNumber == MYIMAGE_SYM_UNDEFINED
2034           && symtab_i->Value > 0) {
2035          /* This symbol isn't in any section at all, ie, global bss.
2036             Allocate zeroed space for it. */
2037          addr = stgCallocBytes(1, symtab_i->Value,
2038                                "ocGetNames_PEi386(non-anonymous bss)");
2039          addSection(oc, SECTIONKIND_RWDATA, addr,
2040                         ((UChar*)addr) + symtab_i->Value - 1);
2041          addProddableBlock(oc, addr, symtab_i->Value);
2042          /* debugBelch("BSS      section at 0x%x\n", addr); */
2043       }
2044
2045       if (addr != NULL ) {
2046          sname = cstring_from_COFF_symbol_name ( symtab_i->Name, strtab );
2047          /* debugBelch("addSymbol %p `%s \n", addr,sname);  */
2048          IF_DEBUG(linker, debugBelch("addSymbol %p `%s'\n", addr,sname);)
2049          ASSERT(i >= 0 && i < oc->n_symbols);
2050          /* cstring_from_COFF_symbol_name always succeeds. */
2051          oc->symbols[i] = sname;
2052          ghciInsertStrHashTable(oc->fileName, symhash, sname, addr);
2053       } else {
2054 #        if 0
2055          debugBelch(
2056                    "IGNORING symbol %d\n"
2057                    "     name `",
2058                    i
2059                  );
2060          printName ( symtab_i->Name, strtab );
2061          debugBelch(
2062                    "'\n"
2063                    "    value 0x%x\n"
2064                    "   1+sec# %d\n"
2065                    "     type 0x%x\n"
2066                    "   sclass 0x%x\n"
2067                    "     nAux %d\n",
2068                    symtab_i->Value,
2069                    (Int32)(symtab_i->SectionNumber),
2070                    (UInt32)symtab_i->Type,
2071                    (UInt32)symtab_i->StorageClass,
2072                    (UInt32)symtab_i->NumberOfAuxSymbols
2073                  );
2074 #        endif
2075       }
2076
2077       i += symtab_i->NumberOfAuxSymbols;
2078       i++;
2079    }
2080
2081    return 1;
2082 }
2083
2084
2085 static int
2086 ocResolve_PEi386 ( ObjectCode* oc )
2087 {
2088    COFF_header*  hdr;
2089    COFF_section* sectab;
2090    COFF_symbol*  symtab;
2091    UChar*        strtab;
2092
2093    UInt32        A;
2094    UInt32        S;
2095    UInt32*       pP;
2096
2097    int i;
2098    UInt32 j, noRelocs;
2099
2100    /* ToDo: should be variable-sized?  But is at least safe in the
2101       sense of buffer-overrun-proof. */
2102    char symbol[1000];
2103    /* debugBelch("resolving for %s\n", oc->fileName); */
2104
2105    hdr = (COFF_header*)(oc->image);
2106    sectab = (COFF_section*) (
2107                ((UChar*)(oc->image))
2108                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2109             );
2110    symtab = (COFF_symbol*) (
2111                ((UChar*)(oc->image))
2112                + hdr->PointerToSymbolTable
2113             );
2114    strtab = ((UChar*)(oc->image))
2115             + hdr->PointerToSymbolTable
2116             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2117
2118    for (i = 0; i < hdr->NumberOfSections; i++) {
2119       COFF_section* sectab_i
2120          = (COFF_section*)
2121            myindex ( sizeof_COFF_section, sectab, i );
2122       COFF_reloc* reltab
2123          = (COFF_reloc*) (
2124               ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
2125            );
2126
2127       /* Ignore sections called which contain stabs debugging
2128          information. */
2129       if (0 == strcmp(".stab", sectab_i->Name)
2130           || 0 == strcmp(".stabstr", sectab_i->Name))
2131          continue;
2132
2133       if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
2134         /* If the relocation field (a short) has overflowed, the
2135          * real count can be found in the first reloc entry.
2136          *
2137          * See Section 4.1 (last para) of the PE spec (rev6.0).
2138          *
2139          * Nov2003 update: the GNU linker still doesn't correctly
2140          * handle the generation of relocatable object files with
2141          * overflown relocations. Hence the output to warn of potential
2142          * troubles.
2143          */
2144         COFF_reloc* rel = (COFF_reloc*)
2145                            myindex ( sizeof_COFF_reloc, reltab, 0 );
2146         noRelocs = rel->VirtualAddress;
2147         debugBelch("WARNING: Overflown relocation field (# relocs found: %u)\n",
2148                    noRelocs);
2149         j = 1;
2150       } else {
2151         noRelocs = sectab_i->NumberOfRelocations;
2152         j = 0;
2153       }
2154
2155
2156       for (; j < noRelocs; j++) {
2157          COFF_symbol* sym;
2158          COFF_reloc* reltab_j
2159             = (COFF_reloc*)
2160               myindex ( sizeof_COFF_reloc, reltab, j );
2161
2162          /* the location to patch */
2163          pP = (UInt32*)(
2164                  ((UChar*)(oc->image))
2165                  + (sectab_i->PointerToRawData
2166                     + reltab_j->VirtualAddress
2167                     - sectab_i->VirtualAddress )
2168               );
2169          /* the existing contents of pP */
2170          A = *pP;
2171          /* the symbol to connect to */
2172          sym = (COFF_symbol*)
2173                myindex ( sizeof_COFF_symbol,
2174                          symtab, reltab_j->SymbolTableIndex );
2175          IF_DEBUG(linker,
2176                   debugBelch(
2177                             "reloc sec %2d num %3d:  type 0x%-4x   "
2178                             "vaddr 0x%-8x   name `",
2179                             i, j,
2180                             (UInt32)reltab_j->Type,
2181                             reltab_j->VirtualAddress );
2182                             printName ( sym->Name, strtab );
2183                             debugBelch("'\n" ));
2184
2185          if (sym->StorageClass == MYIMAGE_SYM_CLASS_STATIC) {
2186             COFF_section* section_sym
2187                = findPEi386SectionCalled ( oc, sym->Name );
2188             if (!section_sym) {
2189                errorBelch("%s: can't find section `%s'", oc->fileName, sym->Name);
2190                return 0;
2191             }
2192             S = ((UInt32)(oc->image))
2193                 + (section_sym->PointerToRawData
2194                    + sym->Value);
2195          } else {
2196             copyName ( sym->Name, strtab, symbol, 1000-1 );
2197             (void*)S = lookupLocalSymbol( oc, symbol );
2198             if ((void*)S != NULL) goto foundit;
2199             (void*)S = lookupSymbol( symbol );
2200             if ((void*)S != NULL) goto foundit;
2201             zapTrailingAtSign ( symbol );
2202             (void*)S = lookupLocalSymbol( oc, symbol );
2203             if ((void*)S != NULL) goto foundit;
2204             (void*)S = lookupSymbol( symbol );
2205             if ((void*)S != NULL) goto foundit;
2206             /* Newline first because the interactive linker has printed "linking..." */
2207             errorBelch("\n%s: unknown symbol `%s'", oc->fileName, symbol);
2208             return 0;
2209            foundit:;
2210          }
2211          checkProddableBlock(oc, pP);
2212          switch (reltab_j->Type) {
2213             case MYIMAGE_REL_I386_DIR32:
2214                *pP = A + S;
2215                break;
2216             case MYIMAGE_REL_I386_REL32:
2217                /* Tricky.  We have to insert a displacement at
2218                   pP which, when added to the PC for the _next_
2219                   insn, gives the address of the target (S).
2220                   Problem is to know the address of the next insn
2221                   when we only know pP.  We assume that this
2222                   literal field is always the last in the insn,
2223                   so that the address of the next insn is pP+4
2224                   -- hence the constant 4.
2225                   Also I don't know if A should be added, but so
2226                   far it has always been zero.
2227
2228                   SOF 05/2005: 'A' (old contents of *pP) have been observed
2229                   to contain values other than zero (the 'wx' object file
2230                   that came with wxhaskell-0.9.4; dunno how it was compiled..).
2231                   So, add displacement to old value instead of asserting
2232                   A to be zero. Fixes wxhaskell-related crashes, and no other
2233                   ill effects have been observed.
2234                   
2235                   Update: the reason why we're seeing these more elaborate
2236                   relocations is due to a switch in how the NCG compiles SRTs 
2237                   and offsets to them from info tables. SRTs live in .(ro)data, 
2238                   while info tables live in .text, causing GAS to emit REL32/DISP32 
2239                   relocations with non-zero values. Adding the displacement is
2240                   the right thing to do.
2241                */
2242                *pP = S - ((UInt32)pP) - 4 + A;
2243                break;
2244             default:
2245                debugBelch("%s: unhandled PEi386 relocation type %d",
2246                      oc->fileName, reltab_j->Type);
2247                return 0;
2248          }
2249
2250       }
2251    }
2252
2253    IF_DEBUG(linker, debugBelch("completed %s", oc->fileName));
2254    return 1;
2255 }
2256
2257 #endif /* defined(OBJFORMAT_PEi386) */
2258
2259
2260 /* --------------------------------------------------------------------------
2261  * ELF specifics
2262  * ------------------------------------------------------------------------*/
2263
2264 #if defined(OBJFORMAT_ELF)
2265
2266 #define FALSE 0
2267 #define TRUE  1
2268
2269 #if defined(sparc_HOST_ARCH)
2270 #  define ELF_TARGET_SPARC  /* Used inside <elf.h> */
2271 #elif defined(i386_HOST_ARCH)
2272 #  define ELF_TARGET_386    /* Used inside <elf.h> */
2273 #elif defined(x86_64_HOST_ARCH)
2274 #  define ELF_TARGET_X64_64
2275 #  define ELF_64BIT
2276 #elif defined (ia64_HOST_ARCH)
2277 #  define ELF_TARGET_IA64   /* Used inside <elf.h> */
2278 #  define ELF_64BIT
2279 #  define ELF_FUNCTION_DESC /* calling convention uses function descriptors */
2280 #  define ELF_NEED_GOT      /* needs Global Offset Table */
2281 #  define ELF_NEED_PLT      /* needs Procedure Linkage Tables */
2282 #endif
2283
2284 #if !defined(openbsd_HOST_OS)
2285 #include <elf.h>
2286 #else
2287 /* openbsd elf has things in different places, with diff names */
2288 #include <elf_abi.h>
2289 #include <machine/reloc.h>
2290 #define R_386_32    RELOC_32
2291 #define R_386_PC32  RELOC_PC32
2292 #endif
2293
2294 /*
2295  * Define a set of types which can be used for both ELF32 and ELF64
2296  */
2297
2298 #ifdef ELF_64BIT
2299 #define ELFCLASS    ELFCLASS64
2300 #define Elf_Addr    Elf64_Addr
2301 #define Elf_Word    Elf64_Word
2302 #define Elf_Sword   Elf64_Sword
2303 #define Elf_Ehdr    Elf64_Ehdr
2304 #define Elf_Phdr    Elf64_Phdr
2305 #define Elf_Shdr    Elf64_Shdr
2306 #define Elf_Sym     Elf64_Sym
2307 #define Elf_Rel     Elf64_Rel
2308 #define Elf_Rela    Elf64_Rela
2309 #define ELF_ST_TYPE ELF64_ST_TYPE
2310 #define ELF_ST_BIND ELF64_ST_BIND
2311 #define ELF_R_TYPE  ELF64_R_TYPE
2312 #define ELF_R_SYM   ELF64_R_SYM
2313 #else
2314 #define ELFCLASS    ELFCLASS32
2315 #define Elf_Addr    Elf32_Addr
2316 #define Elf_Word    Elf32_Word
2317 #define Elf_Sword   Elf32_Sword
2318 #define Elf_Ehdr    Elf32_Ehdr
2319 #define Elf_Phdr    Elf32_Phdr
2320 #define Elf_Shdr    Elf32_Shdr
2321 #define Elf_Sym     Elf32_Sym
2322 #define Elf_Rel     Elf32_Rel
2323 #define Elf_Rela    Elf32_Rela
2324 #ifndef ELF_ST_TYPE
2325 #define ELF_ST_TYPE ELF32_ST_TYPE
2326 #endif
2327 #ifndef ELF_ST_BIND
2328 #define ELF_ST_BIND ELF32_ST_BIND
2329 #endif
2330 #ifndef ELF_R_TYPE
2331 #define ELF_R_TYPE  ELF32_R_TYPE
2332 #endif
2333 #ifndef ELF_R_SYM
2334 #define ELF_R_SYM   ELF32_R_SYM
2335 #endif
2336 #endif
2337
2338
2339 /*
2340  * Functions to allocate entries in dynamic sections.  Currently we simply
2341  * preallocate a large number, and we don't check if a entry for the given
2342  * target already exists (a linear search is too slow).  Ideally these
2343  * entries would be associated with symbols.
2344  */
2345
2346 /* These sizes sufficient to load HSbase + HShaskell98 + a few modules */
2347 #define GOT_SIZE            0x20000
2348 #define FUNCTION_TABLE_SIZE 0x10000
2349 #define PLT_SIZE            0x08000
2350
2351 #ifdef ELF_NEED_GOT
2352 static Elf_Addr got[GOT_SIZE];
2353 static unsigned int gotIndex;
2354 static Elf_Addr gp_val = (Elf_Addr)got;
2355
2356 static Elf_Addr
2357 allocateGOTEntry(Elf_Addr target)
2358 {
2359    Elf_Addr *entry;
2360
2361    if (gotIndex >= GOT_SIZE)
2362       barf("Global offset table overflow");
2363
2364    entry = &got[gotIndex++];
2365    *entry = target;
2366    return (Elf_Addr)entry;
2367 }
2368 #endif
2369
2370 #ifdef ELF_FUNCTION_DESC
2371 typedef struct {
2372    Elf_Addr ip;
2373    Elf_Addr gp;
2374 } FunctionDesc;
2375
2376 static FunctionDesc functionTable[FUNCTION_TABLE_SIZE];
2377 static unsigned int functionTableIndex;
2378
2379 static Elf_Addr
2380 allocateFunctionDesc(Elf_Addr target)
2381 {
2382    FunctionDesc *entry;
2383
2384    if (functionTableIndex >= FUNCTION_TABLE_SIZE)
2385       barf("Function table overflow");
2386
2387    entry = &functionTable[functionTableIndex++];
2388    entry->ip = target;
2389    entry->gp = (Elf_Addr)gp_val;
2390    return (Elf_Addr)entry;
2391 }
2392
2393 static Elf_Addr
2394 copyFunctionDesc(Elf_Addr target)
2395 {
2396    FunctionDesc *olddesc = (FunctionDesc *)target;
2397    FunctionDesc *newdesc;
2398
2399    newdesc = (FunctionDesc *)allocateFunctionDesc(olddesc->ip);
2400    newdesc->gp = olddesc->gp;
2401    return (Elf_Addr)newdesc;
2402 }
2403 #endif
2404
2405 #ifdef ELF_NEED_PLT
2406 #ifdef ia64_HOST_ARCH
2407 static void ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value);
2408 static void ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc);
2409
2410 static unsigned char plt_code[] =
2411 {
2412    /* taken from binutils bfd/elfxx-ia64.c */
2413    0x0b, 0x78, 0x00, 0x02, 0x00, 0x24,  /*   [MMI]       addl r15=0,r1;;    */
2414    0x00, 0x41, 0x3c, 0x30, 0x28, 0xc0,  /*               ld8 r16=[r15],8    */
2415    0x01, 0x08, 0x00, 0x84,              /*               mov r14=r1;;       */
2416    0x11, 0x08, 0x00, 0x1e, 0x18, 0x10,  /*   [MIB]       ld8 r1=[r15]       */
2417    0x60, 0x80, 0x04, 0x80, 0x03, 0x00,  /*               mov b6=r16         */
2418    0x60, 0x00, 0x80, 0x00               /*               br.few b6;;        */
2419 };
2420
2421 /* If we can't get to the function descriptor via gp, take a local copy of it */
2422 #define PLT_RELOC(code, target) { \
2423    Elf64_Sxword rel_value = target - gp_val; \
2424    if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff)) \
2425       ia64_reloc_gprel22((Elf_Addr)code, copyFunctionDesc(target)); \
2426    else \
2427       ia64_reloc_gprel22((Elf_Addr)code, target); \
2428    }
2429 #endif
2430
2431 typedef struct {
2432    unsigned char code[sizeof(plt_code)];
2433 } PLTEntry;
2434
2435 static Elf_Addr
2436 allocatePLTEntry(Elf_Addr target, ObjectCode *oc)
2437 {
2438    PLTEntry *plt = (PLTEntry *)oc->plt;
2439    PLTEntry *entry;
2440
2441    if (oc->pltIndex >= PLT_SIZE)
2442       barf("Procedure table overflow");
2443
2444    entry = &plt[oc->pltIndex++];
2445    memcpy(entry->code, plt_code, sizeof(entry->code));
2446    PLT_RELOC(entry->code, target);
2447    return (Elf_Addr)entry;
2448 }
2449
2450 static unsigned int
2451 PLTSize(void)
2452 {
2453    return (PLT_SIZE * sizeof(PLTEntry));
2454 }
2455 #endif
2456
2457
2458 /*
2459  * Generic ELF functions
2460  */
2461
2462 static char *
2463 findElfSection ( void* objImage, Elf_Word sh_type )
2464 {
2465    char* ehdrC = (char*)objImage;
2466    Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2467    Elf_Shdr* shdr = (Elf_Shdr*)(ehdrC + ehdr->e_shoff);
2468    char* sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
2469    char* ptr = NULL;
2470    int i;
2471
2472    for (i = 0; i < ehdr->e_shnum; i++) {
2473       if (shdr[i].sh_type == sh_type
2474           /* Ignore the section header's string table. */
2475           && i != ehdr->e_shstrndx
2476           /* Ignore string tables named .stabstr, as they contain
2477              debugging info. */
2478           && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
2479          ) {
2480          ptr = ehdrC + shdr[i].sh_offset;
2481          break;
2482       }
2483    }
2484    return ptr;
2485 }
2486
2487 #if defined(ia64_HOST_ARCH)
2488 static Elf_Addr
2489 findElfSegment ( void* objImage, Elf_Addr vaddr )
2490 {
2491    char* ehdrC = (char*)objImage;
2492    Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2493    Elf_Phdr* phdr = (Elf_Phdr*)(ehdrC + ehdr->e_phoff);
2494    Elf_Addr segaddr = 0;
2495    int i;
2496
2497    for (i = 0; i < ehdr->e_phnum; i++) {
2498       segaddr = phdr[i].p_vaddr;
2499       if ((vaddr >= segaddr) && (vaddr < segaddr + phdr[i].p_memsz))
2500               break;
2501    }
2502    return segaddr;
2503 }
2504 #endif
2505
2506 static int
2507 ocVerifyImage_ELF ( ObjectCode* oc )
2508 {
2509    Elf_Shdr* shdr;
2510    Elf_Sym*  stab;
2511    int i, j, nent, nstrtab, nsymtabs;
2512    char* sh_strtab;
2513    char* strtab;
2514
2515    char*     ehdrC = (char*)(oc->image);
2516    Elf_Ehdr* ehdr  = (Elf_Ehdr*)ehdrC;
2517
2518    if (ehdr->e_ident[EI_MAG0] != ELFMAG0 ||
2519        ehdr->e_ident[EI_MAG1] != ELFMAG1 ||
2520        ehdr->e_ident[EI_MAG2] != ELFMAG2 ||
2521        ehdr->e_ident[EI_MAG3] != ELFMAG3) {
2522       errorBelch("%s: not an ELF object", oc->fileName);
2523       return 0;
2524    }
2525
2526    if (ehdr->e_ident[EI_CLASS] != ELFCLASS) {
2527       errorBelch("%s: unsupported ELF format", oc->fileName);
2528       return 0;
2529    }
2530
2531    if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) {
2532        IF_DEBUG(linker,debugBelch( "Is little-endian\n" ));
2533    } else
2534    if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) {
2535        IF_DEBUG(linker,debugBelch( "Is big-endian\n" ));
2536    } else {
2537        errorBelch("%s: unknown endiannness", oc->fileName);
2538        return 0;
2539    }
2540
2541    if (ehdr->e_type != ET_REL) {
2542       errorBelch("%s: not a relocatable object (.o) file", oc->fileName);
2543       return 0;
2544    }
2545    IF_DEBUG(linker, debugBelch( "Is a relocatable object (.o) file\n" ));
2546
2547    IF_DEBUG(linker,debugBelch( "Architecture is " ));
2548    switch (ehdr->e_machine) {
2549       case EM_386:   IF_DEBUG(linker,debugBelch( "x86" )); break;
2550       case EM_SPARC: IF_DEBUG(linker,debugBelch( "sparc" )); break;
2551 #ifdef EM_IA_64
2552       case EM_IA_64: IF_DEBUG(linker,debugBelch( "ia64" )); break;
2553 #endif
2554       case EM_PPC:   IF_DEBUG(linker,debugBelch( "powerpc32" )); break;
2555 #ifdef EM_X86_64
2556       case EM_X86_64: IF_DEBUG(linker,debugBelch( "x86_64" )); break;
2557 #endif
2558       default:       IF_DEBUG(linker,debugBelch( "unknown" ));
2559                      errorBelch("%s: unknown architecture", oc->fileName);
2560                      return 0;
2561    }
2562
2563    IF_DEBUG(linker,debugBelch(
2564              "\nSection header table: start %d, n_entries %d, ent_size %d\n",
2565              ehdr->e_shoff, ehdr->e_shnum, ehdr->e_shentsize  ));
2566
2567    ASSERT (ehdr->e_shentsize == sizeof(Elf_Shdr));
2568
2569    shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
2570
2571    if (ehdr->e_shstrndx == SHN_UNDEF) {
2572       errorBelch("%s: no section header string table", oc->fileName);
2573       return 0;
2574    } else {
2575       IF_DEBUG(linker,debugBelch( "Section header string table is section %d\n",
2576                           ehdr->e_shstrndx));
2577       sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
2578    }
2579
2580    for (i = 0; i < ehdr->e_shnum; i++) {
2581       IF_DEBUG(linker,debugBelch("%2d:  ", i ));
2582       IF_DEBUG(linker,debugBelch("type=%2d  ", (int)shdr[i].sh_type ));
2583       IF_DEBUG(linker,debugBelch("size=%4d  ", (int)shdr[i].sh_size ));
2584       IF_DEBUG(linker,debugBelch("offs=%4d  ", (int)shdr[i].sh_offset ));
2585       IF_DEBUG(linker,debugBelch("  (%p .. %p)  ",
2586                ehdrC + shdr[i].sh_offset,
2587                       ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1));
2588
2589       if (shdr[i].sh_type == SHT_REL) {
2590           IF_DEBUG(linker,debugBelch("Rel  " ));
2591       } else if (shdr[i].sh_type == SHT_RELA) {
2592           IF_DEBUG(linker,debugBelch("RelA " ));
2593       } else {
2594           IF_DEBUG(linker,debugBelch("     "));
2595       }
2596       if (sh_strtab) {
2597           IF_DEBUG(linker,debugBelch("sname=%s\n", sh_strtab + shdr[i].sh_name ));
2598       }
2599    }
2600
2601    IF_DEBUG(linker,debugBelch( "\nString tables" ));
2602    strtab = NULL;
2603    nstrtab = 0;
2604    for (i = 0; i < ehdr->e_shnum; i++) {
2605       if (shdr[i].sh_type == SHT_STRTAB
2606           /* Ignore the section header's string table. */
2607           && i != ehdr->e_shstrndx
2608           /* Ignore string tables named .stabstr, as they contain
2609              debugging info. */
2610           && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
2611          ) {
2612          IF_DEBUG(linker,debugBelch("   section %d is a normal string table", i ));
2613          strtab = ehdrC + shdr[i].sh_offset;
2614          nstrtab++;
2615       }
2616    }
2617    if (nstrtab != 1) {
2618       errorBelch("%s: no string tables, or too many", oc->fileName);
2619       return 0;
2620    }
2621
2622    nsymtabs = 0;
2623    IF_DEBUG(linker,debugBelch( "\nSymbol tables" ));
2624    for (i = 0; i < ehdr->e_shnum; i++) {
2625       if (shdr[i].sh_type != SHT_SYMTAB) continue;
2626       IF_DEBUG(linker,debugBelch( "section %d is a symbol table\n", i ));
2627       nsymtabs++;
2628       stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
2629       nent = shdr[i].sh_size / sizeof(Elf_Sym);
2630       IF_DEBUG(linker,debugBelch( "   number of entries is apparently %d (%d rem)\n",
2631                nent,
2632                shdr[i].sh_size % sizeof(Elf_Sym)
2633              ));
2634       if (0 != shdr[i].sh_size % sizeof(Elf_Sym)) {
2635          errorBelch("%s: non-integral number of symbol table entries", oc->fileName);
2636          return 0;
2637       }
2638       for (j = 0; j < nent; j++) {
2639          IF_DEBUG(linker,debugBelch("   %2d  ", j ));
2640          IF_DEBUG(linker,debugBelch("  sec=%-5d  size=%-3d  val=%5p  ",
2641                              (int)stab[j].st_shndx,
2642                              (int)stab[j].st_size,
2643                              (char*)stab[j].st_value ));
2644
2645          IF_DEBUG(linker,debugBelch("type=" ));
2646          switch (ELF_ST_TYPE(stab[j].st_info)) {
2647             case STT_NOTYPE:  IF_DEBUG(linker,debugBelch("notype " )); break;
2648             case STT_OBJECT:  IF_DEBUG(linker,debugBelch("object " )); break;
2649             case STT_FUNC  :  IF_DEBUG(linker,debugBelch("func   " )); break;
2650             case STT_SECTION: IF_DEBUG(linker,debugBelch("section" )); break;
2651             case STT_FILE:    IF_DEBUG(linker,debugBelch("file   " )); break;
2652             default:          IF_DEBUG(linker,debugBelch("?      " )); break;
2653          }
2654          IF_DEBUG(linker,debugBelch("  " ));
2655
2656          IF_DEBUG(linker,debugBelch("bind=" ));
2657          switch (ELF_ST_BIND(stab[j].st_info)) {
2658             case STB_LOCAL :  IF_DEBUG(linker,debugBelch("local " )); break;
2659             case STB_GLOBAL:  IF_DEBUG(linker,debugBelch("global" )); break;
2660             case STB_WEAK  :  IF_DEBUG(linker,debugBelch("weak  " )); break;
2661             default:          IF_DEBUG(linker,debugBelch("?     " )); break;
2662          }
2663          IF_DEBUG(linker,debugBelch("  " ));
2664
2665          IF_DEBUG(linker,debugBelch("name=%s\n", strtab + stab[j].st_name ));
2666       }
2667    }
2668
2669    if (nsymtabs == 0) {
2670       errorBelch("%s: didn't find any symbol tables", oc->fileName);
2671       return 0;
2672    }
2673
2674    return 1;
2675 }
2676
2677 static int getSectionKind_ELF( Elf_Shdr *hdr, int *is_bss )
2678 {
2679     *is_bss = FALSE;
2680
2681     if (hdr->sh_type == SHT_PROGBITS
2682         && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_EXECINSTR)) {
2683         /* .text-style section */
2684         return SECTIONKIND_CODE_OR_RODATA;
2685     }
2686
2687     if (hdr->sh_type == SHT_PROGBITS
2688             && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
2689             /* .data-style section */
2690             return SECTIONKIND_RWDATA;
2691     }
2692
2693     if (hdr->sh_type == SHT_PROGBITS
2694         && (hdr->sh_flags & SHF_ALLOC) && !(hdr->sh_flags & SHF_WRITE)) {
2695         /* .rodata-style section */
2696         return SECTIONKIND_CODE_OR_RODATA;
2697     }
2698
2699     if (hdr->sh_type == SHT_NOBITS
2700         && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
2701         /* .bss-style section */
2702         *is_bss = TRUE;
2703         return SECTIONKIND_RWDATA;
2704     }
2705
2706     return SECTIONKIND_OTHER;
2707 }
2708
2709
2710 static int
2711 ocGetNames_ELF ( ObjectCode* oc )
2712 {
2713    int i, j, k, nent;
2714    Elf_Sym* stab;
2715
2716    char*     ehdrC    = (char*)(oc->image);
2717    Elf_Ehdr* ehdr     = (Elf_Ehdr*)ehdrC;
2718    char*     strtab   = findElfSection ( ehdrC, SHT_STRTAB );
2719    Elf_Shdr* shdr     = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
2720
2721    ASSERT(symhash != NULL);
2722
2723    if (!strtab) {
2724       errorBelch("%s: no strtab", oc->fileName);
2725       return 0;
2726    }
2727
2728    k = 0;
2729    for (i = 0; i < ehdr->e_shnum; i++) {
2730       /* Figure out what kind of section it is.  Logic derived from
2731          Figure 1.14 ("Special Sections") of the ELF document
2732          ("Portable Formats Specification, Version 1.1"). */
2733       int         is_bss = FALSE;
2734       SectionKind kind   = getSectionKind_ELF(&shdr[i], &is_bss);
2735
2736       if (is_bss && shdr[i].sh_size > 0) {
2737          /* This is a non-empty .bss section.  Allocate zeroed space for
2738             it, and set its .sh_offset field such that
2739             ehdrC + .sh_offset == addr_of_zeroed_space.  */
2740          char* zspace = stgCallocBytes(1, shdr[i].sh_size,
2741                                        "ocGetNames_ELF(BSS)");
2742          shdr[i].sh_offset = ((char*)zspace) - ((char*)ehdrC);
2743          /*
2744          debugBelch("BSS section at 0x%x, size %d\n",
2745                          zspace, shdr[i].sh_size);
2746          */
2747       }
2748
2749       /* fill in the section info */
2750       if (kind != SECTIONKIND_OTHER && shdr[i].sh_size > 0) {
2751          addProddableBlock(oc, ehdrC + shdr[i].sh_offset, shdr[i].sh_size);
2752          addSection(oc, kind, ehdrC + shdr[i].sh_offset,
2753                         ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1);
2754       }
2755
2756       if (shdr[i].sh_type != SHT_SYMTAB) continue;
2757
2758       /* copy stuff into this module's object symbol table */
2759       stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
2760       nent = shdr[i].sh_size / sizeof(Elf_Sym);
2761
2762       oc->n_symbols = nent;
2763       oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
2764                                    "ocGetNames_ELF(oc->symbols)");
2765
2766       for (j = 0; j < nent; j++) {
2767
2768          char  isLocal = FALSE; /* avoids uninit-var warning */
2769          char* ad      = NULL;
2770          char* nm      = strtab + stab[j].st_name;
2771          int   secno   = stab[j].st_shndx;
2772
2773          /* Figure out if we want to add it; if so, set ad to its
2774             address.  Otherwise leave ad == NULL. */
2775
2776          if (secno == SHN_COMMON) {
2777             isLocal = FALSE;
2778             ad = stgCallocBytes(1, stab[j].st_size, "ocGetNames_ELF(COMMON)");
2779             /*
2780             debugBelch("COMMON symbol, size %d name %s\n",
2781                             stab[j].st_size, nm);
2782             */
2783             /* Pointless to do addProddableBlock() for this area,
2784                since the linker should never poke around in it. */
2785          }
2786          else
2787          if ( ( ELF_ST_BIND(stab[j].st_info)==STB_GLOBAL
2788                 || ELF_ST_BIND(stab[j].st_info)==STB_LOCAL
2789               )
2790               /* and not an undefined symbol */
2791               && stab[j].st_shndx != SHN_UNDEF
2792               /* and not in a "special section" */
2793               && stab[j].st_shndx < SHN_LORESERVE
2794               &&
2795               /* and it's a not a section or string table or anything silly */
2796               ( ELF_ST_TYPE(stab[j].st_info)==STT_FUNC ||
2797                 ELF_ST_TYPE(stab[j].st_info)==STT_OBJECT ||
2798                 ELF_ST_TYPE(stab[j].st_info)==STT_NOTYPE
2799               )
2800             ) {
2801             /* Section 0 is the undefined section, hence > and not >=. */
2802             ASSERT(secno > 0 && secno < ehdr->e_shnum);
2803             /*
2804             if (shdr[secno].sh_type == SHT_NOBITS) {
2805                debugBelch("   BSS symbol, size %d off %d name %s\n",
2806                                stab[j].st_size, stab[j].st_value, nm);
2807             }
2808             */
2809             ad = ehdrC + shdr[ secno ].sh_offset + stab[j].st_value;
2810             if (ELF_ST_BIND(stab[j].st_info)==STB_LOCAL) {
2811                isLocal = TRUE;
2812             } else {
2813 #ifdef ELF_FUNCTION_DESC
2814                /* dlsym() and the initialisation table both give us function
2815                 * descriptors, so to be consistent we store function descriptors
2816                 * in the symbol table */
2817                if (ELF_ST_TYPE(stab[j].st_info) == STT_FUNC)
2818                    ad = (char *)allocateFunctionDesc((Elf_Addr)ad);
2819 #endif
2820                IF_DEBUG(linker,debugBelch( "addOTabName(GLOB): %10p  %s %s",
2821                                       ad, oc->fileName, nm ));
2822                isLocal = FALSE;
2823             }
2824          }
2825
2826          /* And the decision is ... */
2827
2828          if (ad != NULL) {
2829             ASSERT(nm != NULL);
2830             oc->symbols[j] = nm;
2831             /* Acquire! */
2832             if (isLocal) {
2833                /* Ignore entirely. */
2834             } else {
2835                ghciInsertStrHashTable(oc->fileName, symhash, nm, ad);
2836             }
2837          } else {
2838             /* Skip. */
2839             IF_DEBUG(linker,debugBelch( "skipping `%s'\n",
2840                                    strtab + stab[j].st_name ));
2841             /*
2842             debugBelch(
2843                     "skipping   bind = %d,  type = %d,  shndx = %d   `%s'\n",
2844                     (int)ELF_ST_BIND(stab[j].st_info),
2845                     (int)ELF_ST_TYPE(stab[j].st_info),
2846                     (int)stab[j].st_shndx,
2847                     strtab + stab[j].st_name
2848                    );
2849             */
2850             oc->symbols[j] = NULL;
2851          }
2852
2853       }
2854    }
2855
2856    return 1;
2857 }
2858
2859 /* Do ELF relocations which lack an explicit addend.  All x86-linux
2860    relocations appear to be of this form. */
2861 static int
2862 do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
2863                          Elf_Shdr* shdr, int shnum,
2864                          Elf_Sym*  stab, char* strtab )
2865 {
2866    int j;
2867    char *symbol;
2868    Elf_Word* targ;
2869    Elf_Rel*  rtab = (Elf_Rel*) (ehdrC + shdr[shnum].sh_offset);
2870    int         nent = shdr[shnum].sh_size / sizeof(Elf_Rel);
2871    int target_shndx = shdr[shnum].sh_info;
2872    int symtab_shndx = shdr[shnum].sh_link;
2873
2874    stab  = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
2875    targ  = (Elf_Word*)(ehdrC + shdr[ target_shndx ].sh_offset);
2876    IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
2877                           target_shndx, symtab_shndx ));
2878
2879    /* Skip sections that we're not interested in. */
2880    {
2881        int is_bss;
2882        SectionKind kind = getSectionKind_ELF(&shdr[target_shndx], &is_bss);
2883        if (kind == SECTIONKIND_OTHER) {
2884            IF_DEBUG(linker,debugBelch( "skipping (target section not loaded)"));
2885            return 1;
2886        }
2887    }
2888
2889    for (j = 0; j < nent; j++) {
2890       Elf_Addr offset = rtab[j].r_offset;
2891       Elf_Addr info   = rtab[j].r_info;
2892
2893       Elf_Addr  P  = ((Elf_Addr)targ) + offset;
2894       Elf_Word* pP = (Elf_Word*)P;
2895       Elf_Addr  A  = *pP;
2896       Elf_Addr  S;
2897       void*     S_tmp;
2898       Elf_Addr  value;
2899
2900       IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p)",
2901                              j, (void*)offset, (void*)info ));
2902       if (!info) {
2903          IF_DEBUG(linker,debugBelch( " ZERO" ));
2904          S = 0;
2905       } else {
2906          Elf_Sym sym = stab[ELF_R_SYM(info)];
2907          /* First see if it is a local symbol. */
2908          if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
2909             /* Yes, so we can get the address directly from the ELF symbol
2910                table. */
2911             symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
2912             S = (Elf_Addr)
2913                 (ehdrC + shdr[ sym.st_shndx ].sh_offset
2914                        + stab[ELF_R_SYM(info)].st_value);
2915
2916          } else {
2917             /* No, so look up the name in our global table. */
2918             symbol = strtab + sym.st_name;
2919             S_tmp = lookupSymbol( symbol );
2920             S = (Elf_Addr)S_tmp;
2921          }
2922          if (!S) {
2923             errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
2924             return 0;
2925          }
2926          IF_DEBUG(linker,debugBelch( "`%s' resolves to %p\n", symbol, (void*)S ));
2927       }
2928
2929       IF_DEBUG(linker,debugBelch( "Reloc: P = %p   S = %p   A = %p\n",
2930                              (void*)P, (void*)S, (void*)A ));
2931       checkProddableBlock ( oc, pP );
2932
2933       value = S + A;
2934
2935       switch (ELF_R_TYPE(info)) {
2936 #        ifdef i386_HOST_ARCH
2937          case R_386_32:   *pP = value;     break;
2938          case R_386_PC32: *pP = value - P; break;
2939 #        endif
2940          default:
2941             errorBelch("%s: unhandled ELF relocation(Rel) type %d\n",
2942                   oc->fileName, ELF_R_TYPE(info));
2943             return 0;
2944       }
2945
2946    }
2947    return 1;
2948 }
2949
2950 /* Do ELF relocations for which explicit addends are supplied.
2951    sparc-solaris relocations appear to be of this form. */
2952 static int
2953 do_Elf_Rela_relocations ( ObjectCode* oc, char* ehdrC,
2954                           Elf_Shdr* shdr, int shnum,
2955                           Elf_Sym*  stab, char* strtab )
2956 {
2957    int j;
2958    char *symbol;
2959    Elf_Addr targ;
2960    Elf_Rela* rtab = (Elf_Rela*) (ehdrC + shdr[shnum].sh_offset);
2961    int         nent = shdr[shnum].sh_size / sizeof(Elf_Rela);
2962    int target_shndx = shdr[shnum].sh_info;
2963    int symtab_shndx = shdr[shnum].sh_link;
2964
2965    stab  = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
2966    targ  = (Elf_Addr) (ehdrC + shdr[ target_shndx ].sh_offset);
2967    IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
2968                           target_shndx, symtab_shndx ));
2969
2970    for (j = 0; j < nent; j++) {
2971 #if defined(DEBUG) || defined(sparc_HOST_ARCH) || defined(ia64_HOST_ARCH) || defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
2972       /* This #ifdef only serves to avoid unused-var warnings. */
2973       Elf_Addr  offset = rtab[j].r_offset;
2974       Elf_Addr  P      = targ + offset;
2975 #endif
2976       Elf_Addr  info   = rtab[j].r_info;
2977       Elf_Addr  A      = rtab[j].r_addend;
2978       Elf_Addr  S;
2979       void*     S_tmp;
2980       Elf_Addr  value;
2981 #     if defined(sparc_HOST_ARCH)
2982       Elf_Word* pP = (Elf_Word*)P;
2983       Elf_Word  w1, w2;
2984 #     elif defined(ia64_HOST_ARCH)
2985       Elf64_Xword *pP = (Elf64_Xword *)P;
2986       Elf_Addr addr;
2987 #     elif defined(powerpc_HOST_ARCH)
2988       Elf_Sword delta;
2989 #     endif
2990
2991       IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p %6p)   ",
2992                              j, (void*)offset, (void*)info,
2993                                 (void*)A ));
2994       if (!info) {
2995          IF_DEBUG(linker,debugBelch( " ZERO" ));
2996          S = 0;
2997       } else {
2998          Elf_Sym sym = stab[ELF_R_SYM(info)];
2999          /* First see if it is a local symbol. */
3000          if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
3001             /* Yes, so we can get the address directly from the ELF symbol
3002                table. */
3003             symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
3004             S = (Elf_Addr)
3005                 (ehdrC + shdr[ sym.st_shndx ].sh_offset
3006                        + stab[ELF_R_SYM(info)].st_value);
3007 #ifdef ELF_FUNCTION_DESC
3008             /* Make a function descriptor for this function */
3009             if (S && ELF_ST_TYPE(sym.st_info) == STT_FUNC) {
3010                S = allocateFunctionDesc(S + A);
3011                A = 0;
3012             }
3013 #endif
3014          } else {
3015             /* No, so look up the name in our global table. */
3016             symbol = strtab + sym.st_name;
3017             S_tmp = lookupSymbol( symbol );
3018             S = (Elf_Addr)S_tmp;
3019
3020 #ifdef ELF_FUNCTION_DESC
3021             /* If a function, already a function descriptor - we would
3022                have to copy it to add an offset. */
3023             if (S && (ELF_ST_TYPE(sym.st_info) == STT_FUNC) && (A != 0))
3024                errorBelch("%s: function %s with addend %p", oc->fileName, symbol, (void *)A);
3025 #endif
3026          }
3027          if (!S) {
3028            errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
3029            return 0;
3030          }
3031          IF_DEBUG(linker,debugBelch( "`%s' resolves to %p", symbol, (void*)S ));
3032       }
3033
3034       IF_DEBUG(linker,debugBelch("Reloc: P = %p   S = %p   A = %p\n",
3035                                         (void*)P, (void*)S, (void*)A ));
3036       /* checkProddableBlock ( oc, (void*)P ); */
3037
3038       value = S + A;
3039
3040       switch (ELF_R_TYPE(info)) {
3041 #        if defined(sparc_HOST_ARCH)
3042          case R_SPARC_WDISP30:
3043             w1 = *pP & 0xC0000000;
3044             w2 = (Elf_Word)((value - P) >> 2);
3045             ASSERT((w2 & 0xC0000000) == 0);
3046             w1 |= w2;
3047             *pP = w1;
3048             break;
3049          case R_SPARC_HI22:
3050             w1 = *pP & 0xFFC00000;
3051             w2 = (Elf_Word)(value >> 10);
3052             ASSERT((w2 & 0xFFC00000) == 0);
3053             w1 |= w2;
3054             *pP = w1;
3055             break;
3056          case R_SPARC_LO10:
3057             w1 = *pP & ~0x3FF;
3058             w2 = (Elf_Word)(value & 0x3FF);
3059             ASSERT((w2 & ~0x3FF) == 0);
3060             w1 |= w2;
3061             *pP = w1;
3062             break;
3063          /* According to the Sun documentation:
3064             R_SPARC_UA32
3065             This relocation type resembles R_SPARC_32, except it refers to an
3066             unaligned word. That is, the word to be relocated must be treated
3067             as four separate bytes with arbitrary alignment, not as a word
3068             aligned according to the architecture requirements.
3069
3070             (JRS: which means that freeloading on the R_SPARC_32 case
3071             is probably wrong, but hey ...)
3072          */
3073          case R_SPARC_UA32:
3074          case R_SPARC_32:
3075             w2 = (Elf_Word)value;
3076             *pP = w2;
3077             break;
3078 #        elif defined(ia64_HOST_ARCH)
3079          case R_IA64_DIR64LSB:
3080          case R_IA64_FPTR64LSB:
3081             *pP = value;
3082             break;
3083          case R_IA64_PCREL64LSB:
3084             *pP = value - P;
3085             break;
3086          case R_IA64_SEGREL64LSB:
3087             addr = findElfSegment(ehdrC, value);
3088             *pP = value - addr;
3089             break;
3090          case R_IA64_GPREL22:
3091             ia64_reloc_gprel22(P, value);
3092             break;
3093          case R_IA64_LTOFF22:
3094          case R_IA64_LTOFF22X:
3095          case R_IA64_LTOFF_FPTR22:
3096             addr = allocateGOTEntry(value);
3097             ia64_reloc_gprel22(P, addr);
3098             break;
3099          case R_IA64_PCREL21B:
3100             ia64_reloc_pcrel21(P, S, oc);
3101             break;
3102          case R_IA64_LDXMOV:
3103             /* This goes with R_IA64_LTOFF22X and points to the load to
3104              * convert into a move.  We don't implement relaxation. */
3105             break;
3106 #        elif defined(powerpc_HOST_ARCH)
3107          case R_PPC_ADDR16_LO:
3108             *(Elf32_Half*) P = value;
3109             break;
3110
3111          case R_PPC_ADDR16_HI:
3112             *(Elf32_Half*) P = value >> 16;
3113             break;
3114  
3115          case R_PPC_ADDR16_HA:
3116             *(Elf32_Half*) P = (value + 0x8000) >> 16;
3117             break;
3118
3119          case R_PPC_ADDR32:
3120             *(Elf32_Word *) P = value;
3121             break;
3122
3123          case R_PPC_REL32:
3124             *(Elf32_Word *) P = value - P;
3125             break;
3126
3127          case R_PPC_REL24:
3128             delta = value - P;
3129
3130             if( delta << 6 >> 6 != delta )
3131             {
3132                value = makeJumpIsland( oc, ELF_R_SYM(info), value );
3133                delta = value - P;
3134
3135                if( value == 0 || delta << 6 >> 6 != delta )
3136                {
3137                   barf( "Unable to make ppcJumpIsland for #%d",
3138                         ELF_R_SYM(info) );
3139                   return 0;
3140                }
3141             }
3142
3143             *(Elf_Word *) P = (*(Elf_Word *) P & 0xfc000003)
3144                                           | (delta & 0x3fffffc);
3145             break;
3146 #        endif
3147
3148 #if x86_64_HOST_OS
3149       case R_X86_64_64:
3150           *(Elf64_Xword *)P = value;
3151           break;
3152
3153       case R_X86_64_PC32:
3154           *(Elf64_Word *)P = (Elf64_Word) (value - P);
3155           break;
3156
3157       case R_X86_64_32:
3158           *(Elf64_Word *)P = (Elf64_Word)value;
3159           break;
3160
3161       case R_X86_64_32S:
3162           *(Elf64_Sword *)P = (Elf64_Sword)value;
3163           break;
3164 #endif
3165
3166          default:
3167             errorBelch("%s: unhandled ELF relocation(RelA) type %d\n",
3168                   oc->fileName, ELF_R_TYPE(info));
3169             return 0;
3170       }
3171
3172    }
3173    return 1;
3174 }
3175
3176 static int
3177 ocResolve_ELF ( ObjectCode* oc )
3178 {
3179    char *strtab;
3180    int   shnum, ok;
3181    Elf_Sym*  stab  = NULL;
3182    char*     ehdrC = (char*)(oc->image);
3183    Elf_Ehdr* ehdr  = (Elf_Ehdr*) ehdrC;
3184    Elf_Shdr* shdr  = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
3185
3186    /* first find "the" symbol table */
3187    stab = (Elf_Sym*) findElfSection ( ehdrC, SHT_SYMTAB );
3188
3189    /* also go find the string table */
3190    strtab = findElfSection ( ehdrC, SHT_STRTAB );
3191
3192    if (stab == NULL || strtab == NULL) {
3193       errorBelch("%s: can't find string or symbol table", oc->fileName);
3194       return 0;
3195    }
3196
3197    /* Process the relocation sections. */
3198    for (shnum = 0; shnum < ehdr->e_shnum; shnum++) {
3199       if (shdr[shnum].sh_type == SHT_REL) {
3200          ok = do_Elf_Rel_relocations ( oc, ehdrC, shdr,
3201                                        shnum, stab, strtab );
3202          if (!ok) return ok;
3203       }
3204       else
3205       if (shdr[shnum].sh_type == SHT_RELA) {
3206          ok = do_Elf_Rela_relocations ( oc, ehdrC, shdr,
3207                                         shnum, stab, strtab );
3208          if (!ok) return ok;
3209       }
3210    }
3211
3212    /* Free the local symbol table; we won't need it again. */
3213    freeHashTable(oc->lochash, NULL);
3214    oc->lochash = NULL;
3215
3216 #if defined(powerpc_HOST_ARCH)
3217    ocFlushInstructionCache( oc );
3218 #endif
3219
3220    return 1;
3221 }
3222
3223 /*
3224  * IA64 specifics
3225  * Instructions are 41 bits long, packed into 128 bit bundles with a 5-bit template
3226  * at the front.  The following utility functions pack and unpack instructions, and
3227  * take care of the most common relocations.
3228  */
3229
3230 #ifdef ia64_HOST_ARCH
3231
3232 static Elf64_Xword
3233 ia64_extract_instruction(Elf64_Xword *target)
3234 {
3235    Elf64_Xword w1, w2;
3236    int slot = (Elf_Addr)target & 3;
3237    (Elf_Addr)target &= ~3;
3238
3239    w1 = *target;
3240    w2 = *(target+1);
3241
3242    switch (slot)
3243    {
3244       case 0:
3245          return ((w1 >> 5) & 0x1ffffffffff);
3246       case 1:
3247          return (w1 >> 46) | ((w2 & 0x7fffff) << 18);
3248       case 2:
3249          return (w2 >> 23);
3250       default:
3251          barf("ia64_extract_instruction: invalid slot %p", target);
3252    }
3253 }
3254
3255 static void
3256 ia64_deposit_instruction(Elf64_Xword *target, Elf64_Xword value)
3257 {
3258    int slot = (Elf_Addr)target & 3;
3259    (Elf_Addr)target &= ~3;
3260
3261    switch (slot)
3262    {
3263       case 0:
3264          *target |= value << 5;
3265          break;
3266       case 1:
3267          *target |= value << 46;
3268          *(target+1) |= value >> 18;
3269          break;
3270       case 2:
3271          *(target+1) |= value << 23;
3272          break;
3273    }
3274 }
3275
3276 static void
3277 ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value)
3278 {
3279    Elf64_Xword instruction;
3280    Elf64_Sxword rel_value;
3281
3282    rel_value = value - gp_val;
3283    if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff))
3284       barf("GP-relative data out of range (address = 0x%lx, gp = 0x%lx)", value, gp_val);
3285
3286    instruction = ia64_extract_instruction((Elf64_Xword *)target);
3287    instruction |= (((rel_value >> 0) & 0x07f) << 13)            /* imm7b */
3288                     | (((rel_value >> 7) & 0x1ff) << 27)        /* imm9d */
3289                     | (((rel_value >> 16) & 0x01f) << 22)       /* imm5c */
3290                     | ((Elf64_Xword)(rel_value < 0) << 36);     /* s */
3291    ia64_deposit_instruction((Elf64_Xword *)target, instruction);
3292 }
3293
3294 static void
3295 ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc)
3296 {
3297    Elf64_Xword instruction;
3298    Elf64_Sxword rel_value;
3299    Elf_Addr entry;
3300
3301    entry = allocatePLTEntry(value, oc);
3302
3303    rel_value = (entry >> 4) - (target >> 4);
3304    if ((rel_value > 0xfffff) || (rel_value < -0xfffff))
3305       barf("PLT entry too far away (entry = 0x%lx, target = 0x%lx)", entry, target);
3306
3307    instruction = ia64_extract_instruction((Elf64_Xword *)target);
3308    instruction |= ((rel_value & 0xfffff) << 13)                 /* imm20b */
3309                     | ((Elf64_Xword)(rel_value < 0) << 36);     /* s */
3310    ia64_deposit_instruction((Elf64_Xword *)target, instruction);
3311 }
3312
3313 #endif /* ia64 */
3314
3315 /*
3316  * PowerPC ELF specifics
3317  */
3318
3319 #ifdef powerpc_HOST_ARCH
3320
3321 static int ocAllocateJumpIslands_ELF( ObjectCode *oc )
3322 {
3323   Elf_Ehdr *ehdr;
3324   Elf_Shdr* shdr;
3325   int i;
3326
3327   ehdr = (Elf_Ehdr *) oc->image;
3328   shdr = (Elf_Shdr *) ( ((char *)oc->image) + ehdr->e_shoff );
3329
3330   for( i = 0; i < ehdr->e_shnum; i++ )
3331     if( shdr[i].sh_type == SHT_SYMTAB )
3332       break;
3333
3334   if( i == ehdr->e_shnum )
3335   {
3336     errorBelch( "This ELF file contains no symtab" );
3337     return 0;
3338   }
3339
3340   if( shdr[i].sh_entsize != sizeof( Elf_Sym ) )
3341   {
3342     errorBelch( "The entry size (%d) of the symtab isn't %d\n",
3343       shdr[i].sh_entsize, sizeof( Elf_Sym ) );
3344     
3345     return 0;
3346   }
3347
3348   return ocAllocateJumpIslands( oc, shdr[i].sh_size / sizeof( Elf_Sym ), 0 );
3349 }
3350
3351 #endif /* powerpc */
3352
3353 #endif /* ELF */
3354
3355 /* --------------------------------------------------------------------------
3356  * Mach-O specifics
3357  * ------------------------------------------------------------------------*/
3358
3359 #if defined(OBJFORMAT_MACHO)
3360
3361 /*
3362   Support for MachO linking on Darwin/MacOS X on PowerPC chips
3363   by Wolfgang Thaller (wolfgang.thaller@gmx.net)
3364
3365   I hereby formally apologize for the hackish nature of this code.
3366   Things that need to be done:
3367   *) implement ocVerifyImage_MachO
3368   *) add still more sanity checks.
3369 */
3370
3371 static int ocAllocateJumpIslands_MachO(ObjectCode* oc)
3372 {
3373     struct mach_header *header = (struct mach_header *) oc->image;
3374     struct load_command *lc = (struct load_command *) (header + 1);
3375     unsigned i;
3376
3377     for( i = 0; i < header->ncmds; i++ )
3378     {   
3379         if( lc->cmd == LC_SYMTAB )
3380         {
3381                 // Find out the first and last undefined external
3382                 // symbol, so we don't have to allocate too many
3383                 // jump islands.
3384             struct symtab_command *symLC = (struct symtab_command *) lc;
3385             unsigned min = symLC->nsyms, max = 0;
3386             struct nlist *nlist =
3387                 symLC ? (struct nlist*) ((char*) oc->image + symLC->symoff)
3388                       : NULL;
3389             for(i=0;i<symLC->nsyms;i++)
3390             {
3391                 if(nlist[i].n_type & N_STAB)
3392                     ;
3393                 else if(nlist[i].n_type & N_EXT)
3394                 {
3395                     if((nlist[i].n_type & N_TYPE) == N_UNDF
3396                         && (nlist[i].n_value == 0))
3397                     {
3398                         if(i < min)
3399                             min = i;
3400                         if(i > max)
3401                             max = i;
3402                     }
3403                 }
3404             }
3405             if(max >= min)
3406                 return ocAllocateJumpIslands(oc, max - min + 1, min);
3407
3408             break;
3409         }
3410         
3411         lc = (struct load_command *) ( ((char *)lc) + lc->cmdsize );
3412     }
3413     return ocAllocateJumpIslands(oc,0,0);
3414 }
3415
3416 static int ocVerifyImage_MachO(ObjectCode* oc STG_UNUSED)
3417 {
3418     // FIXME: do some verifying here
3419     return 1;
3420 }
3421
3422 static int resolveImports(
3423     ObjectCode* oc,
3424     char *image,
3425     struct symtab_command *symLC,
3426     struct section *sect,    // ptr to lazy or non-lazy symbol pointer section
3427     unsigned long *indirectSyms,
3428     struct nlist *nlist)
3429 {
3430     unsigned i;
3431
3432     for(i=0;i*4<sect->size;i++)
3433     {
3434         // according to otool, reserved1 contains the first index into the indirect symbol table
3435         struct nlist *symbol = &nlist[indirectSyms[sect->reserved1+i]];
3436         char *nm = image + symLC->stroff + symbol->n_un.n_strx;
3437         void *addr = NULL;
3438
3439         if((symbol->n_type & N_TYPE) == N_UNDF
3440             && (symbol->n_type & N_EXT) && (symbol->n_value != 0))
3441             addr = (void*) (symbol->n_value);
3442         else if((addr = lookupLocalSymbol(oc,nm)) != NULL)
3443             ;
3444         else
3445             addr = lookupSymbol(nm);
3446         if(!addr)
3447         {
3448             errorBelch("\n%s: unknown symbol `%s'", oc->fileName, nm);
3449             return 0;
3450         }
3451         ASSERT(addr);
3452         checkProddableBlock(oc,((void**)(image + sect->offset)) + i);
3453         ((void**)(image + sect->offset))[i] = addr;
3454     }
3455
3456     return 1;
3457 }
3458
3459 static unsigned long relocateAddress(
3460     ObjectCode* oc,
3461     int nSections,
3462     struct section* sections,
3463     unsigned long address)
3464 {
3465     int i;
3466     for(i = 0; i < nSections; i++)
3467     {
3468         if(sections[i].addr <= address
3469             && address < sections[i].addr + sections[i].size)
3470         {
3471             return (unsigned long)oc->image
3472                     + sections[i].offset + address - sections[i].addr;
3473         }
3474     }
3475     barf("Invalid Mach-O file:"
3476          "Address out of bounds while relocating object file");
3477     return 0;
3478 }
3479
3480 static int relocateSection(
3481     ObjectCode* oc,
3482     char *image,
3483     struct symtab_command *symLC, struct nlist *nlist,
3484     int nSections, struct section* sections, struct section *sect)
3485 {
3486     struct relocation_info *relocs;
3487     int i,n;
3488
3489     if(!strcmp(sect->sectname,"__la_symbol_ptr"))
3490         return 1;
3491     else if(!strcmp(sect->sectname,"__nl_symbol_ptr"))
3492         return 1;
3493
3494     n = sect->nreloc;
3495     relocs = (struct relocation_info*) (image + sect->reloff);
3496
3497     for(i=0;i<n;i++)
3498     {
3499         if(relocs[i].r_address & R_SCATTERED)
3500         {
3501             struct scattered_relocation_info *scat =
3502                 (struct scattered_relocation_info*) &relocs[i];
3503
3504             if(!scat->r_pcrel)
3505             {
3506                 if(scat->r_length == 2)
3507                 {
3508                     unsigned long word = 0;
3509                     unsigned long* wordPtr = (unsigned long*) (image + sect->offset + scat->r_address);
3510                     checkProddableBlock(oc,wordPtr);
3511
3512                     // Step 1: Figure out what the relocated value should be
3513                     if(scat->r_type == GENERIC_RELOC_VANILLA)
3514                     {
3515                         word = *wordPtr + (unsigned long) relocateAddress(
3516                                                                 oc,
3517                                                                 nSections,
3518                                                                 sections,
3519                                                                 scat->r_value)
3520                                         - scat->r_value;
3521                     }
3522                     else if(scat->r_type == PPC_RELOC_SECTDIFF
3523                         || scat->r_type == PPC_RELOC_LO16_SECTDIFF
3524                         || scat->r_type == PPC_RELOC_HI16_SECTDIFF
3525                         || scat->r_type == PPC_RELOC_HA16_SECTDIFF)
3526                     {
3527                         struct scattered_relocation_info *pair =
3528                                 (struct scattered_relocation_info*) &relocs[i+1];
3529
3530                         if(!pair->r_scattered || pair->r_type != PPC_RELOC_PAIR)
3531                             barf("Invalid Mach-O file: "
3532                                  "PPC_RELOC_*_SECTDIFF not followed by PPC_RELOC_PAIR");
3533
3534                         word = (unsigned long)
3535                                (relocateAddress(oc, nSections, sections, scat->r_value)
3536                               - relocateAddress(oc, nSections, sections, pair->r_value));
3537                         i++;
3538                     }
3539                     else if(scat->r_type == PPC_RELOC_HI16
3540                          || scat->r_type == PPC_RELOC_LO16
3541                          || scat->r_type == PPC_RELOC_HA16
3542                          || scat->r_type == PPC_RELOC_LO14)
3543                     {   // these are generated by label+offset things
3544                         struct relocation_info *pair = &relocs[i+1];
3545                         if((pair->r_address & R_SCATTERED) || pair->r_type != PPC_RELOC_PAIR)
3546                             barf("Invalid Mach-O file: "
3547                                  "PPC_RELOC_* not followed by PPC_RELOC_PAIR");
3548                         
3549                         if(scat->r_type == PPC_RELOC_LO16)
3550                         {
3551                             word = ((unsigned short*) wordPtr)[1];
3552                             word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
3553                         }
3554                         else if(scat->r_type == PPC_RELOC_LO14)
3555                         {
3556                             barf("Unsupported Relocation: PPC_RELOC_LO14");
3557                             word = ((unsigned short*) wordPtr)[1] & 0xFFFC;
3558                             word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
3559                         }
3560                         else if(scat->r_type == PPC_RELOC_HI16)
3561                         {
3562                             word = ((unsigned short*) wordPtr)[1] << 16;
3563                             word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
3564                         }
3565                         else if(scat->r_type == PPC_RELOC_HA16)
3566                         {
3567                             word = ((unsigned short*) wordPtr)[1] << 16;
3568                             word += ((short)relocs[i+1].r_address & (short)0xFFFF);
3569                         }
3570                        
3571                         
3572                         word += (unsigned long) relocateAddress(oc, nSections, sections, scat->r_value)
3573                                                 - scat->r_value;
3574                         
3575                         i++;
3576                     }
3577                     else
3578                         continue;  // ignore the others
3579
3580                     if(scat->r_type == GENERIC_RELOC_VANILLA
3581                         || scat->r_type == PPC_RELOC_SECTDIFF)
3582                     {
3583                         *wordPtr = word;
3584                     }
3585                     else if(scat->r_type == PPC_RELOC_LO16_SECTDIFF || scat->r_type == PPC_RELOC_LO16)
3586                     {
3587                         ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
3588                     }
3589                     else if(scat->r_type == PPC_RELOC_HI16_SECTDIFF || scat->r_type == PPC_RELOC_HI16)
3590                     {
3591                         ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
3592                     }
3593                     else if(scat->r_type == PPC_RELOC_HA16_SECTDIFF || scat->r_type == PPC_RELOC_HA16)
3594                     {
3595                         ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
3596                             + ((word & (1<<15)) ? 1 : 0);
3597                     }
3598                 }
3599             }
3600
3601             continue; // FIXME: I hope it's OK to ignore all the others.
3602         }
3603         else
3604         {
3605             struct relocation_info *reloc = &relocs[i];
3606             if(reloc->r_pcrel && !reloc->r_extern)
3607                 continue;
3608
3609             if(reloc->r_length == 2)
3610             {
3611                 unsigned long word = 0;
3612                 unsigned long jumpIsland = 0;
3613                 long offsetToJumpIsland = 0xBADBAD42; // initialise to bad value
3614                                                       // to avoid warning and to catch
3615                                                       // bugs.
3616
3617                 unsigned long* wordPtr = (unsigned long*) (image + sect->offset + reloc->r_address);
3618                 checkProddableBlock(oc,wordPtr);
3619
3620                 if(reloc->r_type == GENERIC_RELOC_VANILLA)
3621                 {
3622                     word = *wordPtr;
3623                 }
3624                 else if(reloc->r_type == PPC_RELOC_LO16)
3625                 {
3626                     word = ((unsigned short*) wordPtr)[1];
3627                     word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
3628                 }
3629                 else if(reloc->r_type == PPC_RELOC_HI16)
3630                 {
3631                     word = ((unsigned short*) wordPtr)[1] << 16;
3632                     word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
3633                 }
3634                 else if(reloc->r_type == PPC_RELOC_HA16)
3635                 {
3636                     word = ((unsigned short*) wordPtr)[1] << 16;
3637                     word += ((short)relocs[i+1].r_address & (short)0xFFFF);
3638                 }
3639                 else if(reloc->r_type == PPC_RELOC_BR24)
3640                 {
3641                     word = *wordPtr;
3642                     word = (word & 0x03FFFFFC) | ((word & 0x02000000) ? 0xFC000000 : 0);
3643                 }
3644
3645
3646                 if(!reloc->r_extern)
3647                 {
3648                     long delta =
3649                         sections[reloc->r_symbolnum-1].offset
3650                         - sections[reloc->r_symbolnum-1].addr
3651                         + ((long) image);
3652
3653                     word += delta;
3654                 }
3655                 else
3656                 {
3657                     struct nlist *symbol = &nlist[reloc->r_symbolnum];
3658                     char *nm = image + symLC->stroff + symbol->n_un.n_strx;
3659                     void *symbolAddress = lookupSymbol(nm);
3660                     if(!symbolAddress)
3661                     {
3662                         errorBelch("\nunknown symbol `%s'", nm);
3663                         return 0;
3664                     }
3665
3666                     if(reloc->r_pcrel)
3667                     {  
3668                             // In the .o file, this should be a relative jump to NULL
3669                             // and we'll change it to a jump to a relative jump to the symbol
3670                         ASSERT(-word == reloc->r_address);
3671                         word = (unsigned long) symbolAddress;
3672                         jumpIsland = makeJumpIsland(oc,reloc->r_symbolnum,word);
3673                         word -= ((long)image) + sect->offset + reloc->r_address;
3674                         if(jumpIsland != 0)
3675                         {
3676                             offsetToJumpIsland = jumpIsland
3677                                 - (((long)image) + sect->offset + reloc->r_address);
3678                         }
3679                     }
3680                     else
3681                     {
3682                         word += (unsigned long) symbolAddress;
3683                     }
3684                 }
3685
3686                 if(reloc->r_type == GENERIC_RELOC_VANILLA)
3687                 {
3688                     *wordPtr = word;
3689                     continue;
3690                 }
3691                 else if(reloc->r_type == PPC_RELOC_LO16)
3692                 {
3693                     ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
3694                     i++; continue;
3695                 }
3696                 else if(reloc->r_type == PPC_RELOC_HI16)
3697                 {
3698                     ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
3699                     i++; continue;
3700                 }
3701                 else if(reloc->r_type == PPC_RELOC_HA16)
3702                 {
3703                     ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
3704                         + ((word & (1<<15)) ? 1 : 0);
3705                     i++; continue;
3706                 }
3707                 else if(reloc->r_type == PPC_RELOC_BR24)
3708                 {
3709                     if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
3710                     {
3711                         // The branch offset is too large.
3712                         // Therefore, we try to use a jump island.
3713                         if(jumpIsland == 0)
3714                         {
3715                             barf("unconditional relative branch out of range: "
3716                                  "no jump island available");
3717                         }
3718                         
3719                         word = offsetToJumpIsland;
3720                         if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
3721                             barf("unconditional relative branch out of range: "
3722                                  "jump island out of range");
3723                     }
3724                     *wordPtr = (*wordPtr & 0xFC000003) | (word & 0x03FFFFFC);
3725                     continue;
3726                 }
3727             }
3728             barf("\nunknown relocation %d",reloc->r_type);
3729             return 0;
3730         }
3731     }
3732     return 1;
3733 }
3734
3735 static int ocGetNames_MachO(ObjectCode* oc)
3736 {
3737     char *image = (char*) oc->image;
3738     struct mach_header *header = (struct mach_header*) image;
3739     struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
3740     unsigned i,curSymbol = 0;
3741     struct segment_command *segLC = NULL;
3742     struct section *sections;
3743     struct symtab_command *symLC = NULL;
3744     struct nlist *nlist;
3745     unsigned long commonSize = 0;
3746     char    *commonStorage = NULL;
3747     unsigned long commonCounter;
3748
3749     for(i=0;i<header->ncmds;i++)
3750     {
3751         if(lc->cmd == LC_SEGMENT)
3752             segLC = (struct segment_command*) lc;
3753         else if(lc->cmd == LC_SYMTAB)
3754             symLC = (struct symtab_command*) lc;
3755         lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
3756     }
3757
3758     sections = (struct section*) (segLC+1);
3759     nlist = symLC ? (struct nlist*) (image + symLC->symoff)
3760                   : NULL;
3761
3762     for(i=0;i<segLC->nsects;i++)
3763     {
3764         if(sections[i].size == 0)
3765             continue;
3766
3767         if((sections[i].flags & SECTION_TYPE) == S_ZEROFILL)
3768         {
3769             char * zeroFillArea = stgCallocBytes(1,sections[i].size,
3770                                       "ocGetNames_MachO(common symbols)");
3771             sections[i].offset = zeroFillArea - image;
3772         }
3773
3774         if(!strcmp(sections[i].sectname,"__text"))
3775             addSection(oc, SECTIONKIND_CODE_OR_RODATA,
3776                 (void*) (image + sections[i].offset),
3777                 (void*) (image + sections[i].offset + sections[i].size));
3778         else if(!strcmp(sections[i].sectname,"__const"))
3779             addSection(oc, SECTIONKIND_RWDATA,
3780                 (void*) (image + sections[i].offset),
3781                 (void*) (image + sections[i].offset + sections[i].size));
3782         else if(!strcmp(sections[i].sectname,"__data"))
3783             addSection(oc, SECTIONKIND_RWDATA,
3784                 (void*) (image + sections[i].offset),
3785                 (void*) (image + sections[i].offset + sections[i].size));
3786         else if(!strcmp(sections[i].sectname,"__bss")
3787                 || !strcmp(sections[i].sectname,"__common"))
3788             addSection(oc, SECTIONKIND_RWDATA,
3789                 (void*) (image + sections[i].offset),
3790                 (void*) (image + sections[i].offset + sections[i].size));
3791
3792         addProddableBlock(oc, (void*) (image + sections[i].offset),
3793                                         sections[i].size);
3794     }
3795
3796         // count external symbols defined here
3797     oc->n_symbols = 0;
3798     if(symLC)
3799     {
3800         for(i=0;i<symLC->nsyms;i++)
3801         {
3802             if(nlist[i].n_type & N_STAB)
3803                 ;
3804             else if(nlist[i].n_type & N_EXT)
3805             {
3806                 if((nlist[i].n_type & N_TYPE) == N_UNDF
3807                     && (nlist[i].n_value != 0))
3808                 {
3809                     commonSize += nlist[i].n_value;
3810                     oc->n_symbols++;
3811                 }
3812                 else if((nlist[i].n_type & N_TYPE) == N_SECT)
3813                     oc->n_symbols++;
3814             }
3815         }
3816     }
3817     oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
3818                                    "ocGetNames_MachO(oc->symbols)");
3819
3820     if(symLC)
3821     {
3822         for(i=0;i<symLC->nsyms;i++)
3823         {
3824             if(nlist[i].n_type & N_STAB)
3825                 ;
3826             else if((nlist[i].n_type & N_TYPE) == N_SECT)
3827             {
3828                 if(nlist[i].n_type & N_EXT)
3829                 {
3830                     char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
3831                     ghciInsertStrHashTable(oc->fileName, symhash, nm,
3832                                             image
3833                                             + sections[nlist[i].n_sect-1].offset
3834                                             - sections[nlist[i].n_sect-1].addr
3835                                             + nlist[i].n_value);
3836                     oc->symbols[curSymbol++] = nm;
3837                 }
3838                 else
3839                 {
3840                     char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
3841                     ghciInsertStrHashTable(oc->fileName, oc->lochash, nm,
3842                                             image
3843                                             + sections[nlist[i].n_sect-1].offset
3844                                             - sections[nlist[i].n_sect-1].addr
3845                                             + nlist[i].n_value);
3846                 }
3847             }
3848         }
3849     }
3850
3851     commonStorage = stgCallocBytes(1,commonSize,"ocGetNames_MachO(common symbols)");
3852     commonCounter = (unsigned long)commonStorage;
3853     if(symLC)
3854     {
3855         for(i=0;i<symLC->nsyms;i++)
3856         {
3857             if((nlist[i].n_type & N_TYPE) == N_UNDF
3858                     && (nlist[i].n_type & N_EXT) && (nlist[i].n_value != 0))
3859             {
3860                 char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
3861                 unsigned long sz = nlist[i].n_value;
3862
3863                 nlist[i].n_value = commonCounter;
3864
3865                 ghciInsertStrHashTable(oc->fileName, symhash, nm,
3866                                        (void*)commonCounter);
3867                 oc->symbols[curSymbol++] = nm;
3868
3869                 commonCounter += sz;
3870             }
3871         }
3872     }
3873     return 1;
3874 }
3875
3876 static int ocResolve_MachO(ObjectCode* oc)
3877 {
3878     char *image = (char*) oc->image;
3879     struct mach_header *header = (struct mach_header*) image;
3880     struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
3881     unsigned i;
3882     struct segment_command *segLC = NULL;
3883     struct section *sections, *la_ptrs = NULL, *nl_ptrs = NULL;
3884     struct symtab_command *symLC = NULL;
3885     struct dysymtab_command *dsymLC = NULL;
3886     struct nlist *nlist;
3887
3888     for(i=0;i<header->ncmds;i++)
3889     {
3890         if(lc->cmd == LC_SEGMENT)
3891             segLC = (struct segment_command*) lc;
3892         else if(lc->cmd == LC_SYMTAB)
3893             symLC = (struct symtab_command*) lc;
3894         else if(lc->cmd == LC_DYSYMTAB)
3895             dsymLC = (struct dysymtab_command*) lc;
3896         lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
3897     }
3898
3899     sections = (struct section*) (segLC+1);
3900     nlist = symLC ? (struct nlist*) (image + symLC->symoff)
3901                   : NULL;
3902
3903     for(i=0;i<segLC->nsects;i++)
3904     {
3905         if(!strcmp(sections[i].sectname,"__la_symbol_ptr"))
3906             la_ptrs = &sections[i];
3907         else if(!strcmp(sections[i].sectname,"__nl_symbol_ptr"))
3908             nl_ptrs = &sections[i];
3909     }
3910
3911     if(dsymLC)
3912     {
3913         unsigned long *indirectSyms
3914             = (unsigned long*) (image + dsymLC->indirectsymoff);
3915
3916         if(la_ptrs)
3917             if(!resolveImports(oc,image,symLC,la_ptrs,indirectSyms,nlist))
3918                 return 0;
3919         if(nl_ptrs)
3920             if(!resolveImports(oc,image,symLC,nl_ptrs,indirectSyms,nlist))
3921                 return 0;
3922     }
3923     
3924     for(i=0;i<segLC->nsects;i++)
3925     {
3926         if(!relocateSection(oc,image,symLC,nlist,segLC->nsects,sections,&sections[i]))
3927             return 0;
3928     }
3929
3930     /* Free the local symbol table; we won't need it again. */
3931     freeHashTable(oc->lochash, NULL);
3932     oc->lochash = NULL;
3933
3934 #if defined (powerpc_HOST_ARCH)
3935     ocFlushInstructionCache( oc );
3936 #endif
3937
3938     return 1;
3939 }
3940
3941 /*
3942  * The Mach-O object format uses leading underscores. But not everywhere.
3943  * There is a small number of runtime support functions defined in
3944  * libcc_dynamic.a whose name does not have a leading underscore.
3945  * As a consequence, we can't get their address from C code.
3946  * We have to use inline assembler just to take the address of a function.
3947  * Yuck.
3948  */
3949
3950 static void machoInitSymbolsWithoutUnderscore()
3951 {
3952     extern void* symbolsWithoutUnderscore[];
3953     void **p = symbolsWithoutUnderscore;
3954     __asm__ volatile(".globl _symbolsWithoutUnderscore\n.data\n_symbolsWithoutUnderscore:");
3955
3956 #undef Sym
3957 #define Sym(x)  \
3958     __asm__ volatile(".long " # x);
3959
3960     RTS_MACHO_NOUNDERLINE_SYMBOLS
3961
3962     __asm__ volatile(".text");
3963     
3964 #undef Sym
3965 #define Sym(x)  \
3966     ghciInsertStrHashTable("(GHCi built-in symbols)", symhash, #x, *p++);
3967     
3968     RTS_MACHO_NOUNDERLINE_SYMBOLS
3969     
3970 #undef Sym
3971 }
3972 #endif