1 /* -----------------------------------------------------------------------------
3 * (c) The GHC Team, 2000-2004
7 * ---------------------------------------------------------------------------*/
10 #include "PosixSource.h"
13 /* Linux needs _GNU_SOURCE to get RTLD_DEFAULT from <dlfcn.h> and
14 MREMAP_MAYMOVE from <sys/mman.h>.
25 #include "LinkerInternals.h"
29 #include "RtsTypeable.h"
31 #ifdef HAVE_SYS_TYPES_H
32 #include <sys/types.h>
38 #ifdef HAVE_SYS_STAT_H
42 #if defined(HAVE_DLFCN_H)
46 #if defined(cygwin32_HOST_OS)
51 #ifdef HAVE_SYS_TIME_H
55 #include <sys/fcntl.h>
56 #include <sys/termios.h>
57 #include <sys/utime.h>
58 #include <sys/utsname.h>
62 #if defined(ia64_HOST_ARCH) || defined(openbsd_HOST_OS) || defined(linux_HOST_OS) || defined(freebsd_HOST_OS)
67 #if defined(openbsd_HOST_OS) || defined(linux_HOST_OS) || defined(freebsd_HOST_OS)
75 #if defined(linux_HOST_OS) || defined(solaris2_HOST_OS) || defined(freebsd_HOST_OS) || defined(netbsd_HOST_OS) || defined(openbsd_HOST_OS)
76 # define OBJFORMAT_ELF
77 #elif defined(cygwin32_HOST_OS) || defined (mingw32_HOST_OS)
78 # define OBJFORMAT_PEi386
81 #elif defined(darwin_HOST_OS)
82 # define OBJFORMAT_MACHO
83 # include <mach-o/loader.h>
84 # include <mach-o/nlist.h>
85 # include <mach-o/reloc.h>
86 #if !defined(HAVE_DLFCN_H)
87 # include <mach-o/dyld.h>
89 #if defined(powerpc_HOST_ARCH)
90 # include <mach-o/ppc/reloc.h>
92 #if defined(x86_64_HOST_ARCH)
93 # include <mach-o/x86_64/reloc.h>
97 /* Hash table mapping symbol names to Symbol */
98 static /*Str*/HashTable *symhash;
100 /* Hash table mapping symbol names to StgStablePtr */
101 static /*Str*/HashTable *stablehash;
103 /* List of currently loaded objects */
104 ObjectCode *objects = NULL; /* initially empty */
106 #if defined(OBJFORMAT_ELF)
107 static int ocVerifyImage_ELF ( ObjectCode* oc );
108 static int ocGetNames_ELF ( ObjectCode* oc );
109 static int ocResolve_ELF ( ObjectCode* oc );
110 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
111 static int ocAllocateSymbolExtras_ELF ( ObjectCode* oc );
113 #elif defined(OBJFORMAT_PEi386)
114 static int ocVerifyImage_PEi386 ( ObjectCode* oc );
115 static int ocGetNames_PEi386 ( ObjectCode* oc );
116 static int ocResolve_PEi386 ( ObjectCode* oc );
117 #elif defined(OBJFORMAT_MACHO)
118 static int ocVerifyImage_MachO ( ObjectCode* oc );
119 static int ocGetNames_MachO ( ObjectCode* oc );
120 static int ocResolve_MachO ( ObjectCode* oc );
122 static int machoGetMisalignment( FILE * );
123 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
124 static int ocAllocateSymbolExtras_MachO ( ObjectCode* oc );
126 #ifdef powerpc_HOST_ARCH
127 static void machoInitSymbolsWithoutUnderscore( void );
131 /* on x86_64 we have a problem with relocating symbol references in
132 * code that was compiled without -fPIC. By default, the small memory
133 * model is used, which assumes that symbol references can fit in a
134 * 32-bit slot. The system dynamic linker makes this work for
135 * references to shared libraries by either (a) allocating a jump
136 * table slot for code references, or (b) moving the symbol at load
137 * time (and copying its contents, if necessary) for data references.
139 * We unfortunately can't tell whether symbol references are to code
140 * or data. So for now we assume they are code (the vast majority
141 * are), and allocate jump-table slots. Unfortunately this will
142 * SILENTLY generate crashing code for data references. This hack is
143 * enabled by X86_64_ELF_NONPIC_HACK.
145 * One workaround is to use shared Haskell libraries. This is
146 * coming. Another workaround is to keep the static libraries but
147 * compile them with -fPIC, because that will generate PIC references
148 * to data which can be relocated. The PIC code is still too green to
149 * do this systematically, though.
152 * See thread http://www.haskell.org/pipermail/cvs-ghc/2007-September/038458.html
154 #define X86_64_ELF_NONPIC_HACK 1
156 /* -----------------------------------------------------------------------------
157 * Built-in symbols from the RTS
160 typedef struct _RtsSymbolVal {
167 #define Maybe_Stable_Names SymX(mkWeakzh_fast) \
168 SymX(makeStableNamezh_fast) \
169 SymX(finalizzeWeakzh_fast)
171 /* These are not available in GUM!!! -- HWL */
172 #define Maybe_Stable_Names
175 #if !defined (mingw32_HOST_OS)
176 #define RTS_POSIX_ONLY_SYMBOLS \
179 SymX(signal_handlers) \
180 SymX(stg_sig_install) \
184 #if defined (cygwin32_HOST_OS)
185 #define RTS_MINGW_ONLY_SYMBOLS /**/
186 /* Don't have the ability to read import libs / archives, so
187 * we have to stupidly list a lot of what libcygwin.a
190 #define RTS_CYGWIN_ONLY_SYMBOLS \
268 #elif !defined(mingw32_HOST_OS)
269 #define RTS_MINGW_ONLY_SYMBOLS /**/
270 #define RTS_CYGWIN_ONLY_SYMBOLS /**/
271 #else /* defined(mingw32_HOST_OS) */
272 #define RTS_POSIX_ONLY_SYMBOLS /**/
273 #define RTS_CYGWIN_ONLY_SYMBOLS /**/
275 /* Extra syms gen'ed by mingw-2's gcc-3.2: */
277 #define RTS_MINGW_EXTRA_SYMS \
278 Sym(_imp____mb_cur_max) \
281 #define RTS_MINGW_EXTRA_SYMS
284 #if HAVE_GETTIMEOFDAY
285 #define RTS_MINGW_GETTIMEOFDAY_SYM Sym(gettimeofday)
287 #define RTS_MINGW_GETTIMEOFDAY_SYM /**/
290 /* These are statically linked from the mingw libraries into the ghc
291 executable, so we have to employ this hack. */
292 #define RTS_MINGW_ONLY_SYMBOLS \
293 SymX(asyncReadzh_fast) \
294 SymX(asyncWritezh_fast) \
295 SymX(asyncDoProczh_fast) \
307 SymX(getservbyname) \
308 SymX(getservbyport) \
309 SymX(getprotobynumber) \
310 SymX(getprotobyname) \
311 SymX(gethostbyname) \
312 SymX(gethostbyaddr) \
359 SymX(rts_InstallConsoleEvent) \
360 SymX(rts_ConsoleHandlerDone) \
362 Sym(_imp___timezone) \
372 RTS_MINGW_EXTRA_SYMS \
373 RTS_MINGW_GETTIMEOFDAY_SYM \
377 #if defined(darwin_TARGET_OS) && HAVE_PRINTF_LDBLSTUB
378 #define RTS_DARWIN_ONLY_SYMBOLS \
379 Sym(asprintf$LDBLStub) \
383 Sym(fprintf$LDBLStub) \
384 Sym(fscanf$LDBLStub) \
385 Sym(fwprintf$LDBLStub) \
386 Sym(fwscanf$LDBLStub) \
387 Sym(printf$LDBLStub) \
388 Sym(scanf$LDBLStub) \
389 Sym(snprintf$LDBLStub) \
390 Sym(sprintf$LDBLStub) \
391 Sym(sscanf$LDBLStub) \
392 Sym(strtold$LDBLStub) \
393 Sym(swprintf$LDBLStub) \
394 Sym(swscanf$LDBLStub) \
395 Sym(syslog$LDBLStub) \
396 Sym(vasprintf$LDBLStub) \
398 Sym(verrc$LDBLStub) \
399 Sym(verrx$LDBLStub) \
400 Sym(vfprintf$LDBLStub) \
401 Sym(vfscanf$LDBLStub) \
402 Sym(vfwprintf$LDBLStub) \
403 Sym(vfwscanf$LDBLStub) \
404 Sym(vprintf$LDBLStub) \
405 Sym(vscanf$LDBLStub) \
406 Sym(vsnprintf$LDBLStub) \
407 Sym(vsprintf$LDBLStub) \
408 Sym(vsscanf$LDBLStub) \
409 Sym(vswprintf$LDBLStub) \
410 Sym(vswscanf$LDBLStub) \
411 Sym(vsyslog$LDBLStub) \
412 Sym(vwarn$LDBLStub) \
413 Sym(vwarnc$LDBLStub) \
414 Sym(vwarnx$LDBLStub) \
415 Sym(vwprintf$LDBLStub) \
416 Sym(vwscanf$LDBLStub) \
418 Sym(warnc$LDBLStub) \
419 Sym(warnx$LDBLStub) \
420 Sym(wcstold$LDBLStub) \
421 Sym(wprintf$LDBLStub) \
424 #define RTS_DARWIN_ONLY_SYMBOLS
428 # define MAIN_CAP_SYM SymX(MainCapability)
430 # define MAIN_CAP_SYM
433 #if !defined(mingw32_HOST_OS)
434 #define RTS_USER_SIGNALS_SYMBOLS \
435 SymX(setIOManagerPipe)
437 #define RTS_USER_SIGNALS_SYMBOLS \
438 SymX(sendIOManagerEvent) \
439 SymX(readIOManagerEvent) \
440 SymX(getIOManagerEvent) \
441 SymX(console_handler)
444 #define RTS_LIBFFI_SYMBOLS \
448 Sym(ffi_type_float) \
449 Sym(ffi_type_double) \
450 Sym(ffi_type_sint64) \
451 Sym(ffi_type_uint64) \
452 Sym(ffi_type_sint32) \
453 Sym(ffi_type_uint32) \
454 Sym(ffi_type_sint16) \
455 Sym(ffi_type_uint16) \
456 Sym(ffi_type_sint8) \
457 Sym(ffi_type_uint8) \
458 Sym(ffi_type_pointer)
460 #ifdef TABLES_NEXT_TO_CODE
461 #define RTS_RET_SYMBOLS /* nothing */
463 #define RTS_RET_SYMBOLS \
464 SymX(stg_enter_ret) \
465 SymX(stg_gc_fun_ret) \
472 SymX(stg_ap_pv_ret) \
473 SymX(stg_ap_pp_ret) \
474 SymX(stg_ap_ppv_ret) \
475 SymX(stg_ap_ppp_ret) \
476 SymX(stg_ap_pppv_ret) \
477 SymX(stg_ap_pppp_ret) \
478 SymX(stg_ap_ppppp_ret) \
479 SymX(stg_ap_pppppp_ret)
482 /* On Windows, we link libgmp.a statically into libHSrts.dll */
483 #ifdef mingw32_HOST_OS
486 SymX(__gmpz_cmp_si) \
487 SymX(__gmpz_cmp_ui) \
488 SymX(__gmpz_get_si) \
492 SymExtern(__gmpz_cmp) \
493 SymExtern(__gmpz_cmp_si) \
494 SymExtern(__gmpz_cmp_ui) \
495 SymExtern(__gmpz_get_si) \
496 SymExtern(__gmpz_get_ui)
499 #define RTS_SYMBOLS \
502 SymX(stg_enter_info) \
503 SymX(stg_gc_void_info) \
504 SymX(__stg_gc_enter_1) \
505 SymX(stg_gc_noregs) \
506 SymX(stg_gc_unpt_r1_info) \
507 SymX(stg_gc_unpt_r1) \
508 SymX(stg_gc_unbx_r1_info) \
509 SymX(stg_gc_unbx_r1) \
510 SymX(stg_gc_f1_info) \
512 SymX(stg_gc_d1_info) \
514 SymX(stg_gc_l1_info) \
517 SymX(stg_gc_fun_info) \
519 SymX(stg_gc_gen_info) \
520 SymX(stg_gc_gen_hp) \
522 SymX(stg_gen_yield) \
523 SymX(stg_yield_noregs) \
524 SymX(stg_yield_to_interpreter) \
525 SymX(stg_gen_block) \
526 SymX(stg_block_noregs) \
528 SymX(stg_block_takemvar) \
529 SymX(stg_block_putmvar) \
531 SymX(MallocFailHook) \
533 SymX(OutOfHeapHook) \
534 SymX(StackOverflowHook) \
535 SymX(__encodeDouble) \
536 SymX(__encodeFloat) \
539 SymX(__int_encodeDouble) \
540 SymX(__2Int_encodeDouble) \
541 SymX(__int_encodeFloat) \
542 SymX(andIntegerzh_fast) \
543 SymX(atomicallyzh_fast) \
547 SymX(blockAsyncExceptionszh_fast) \
549 SymX(catchRetryzh_fast) \
550 SymX(catchSTMzh_fast) \
552 SymX(closure_flags) \
554 SymX(cmpIntegerzh_fast) \
555 SymX(cmpIntegerIntzh_fast) \
556 SymX(complementIntegerzh_fast) \
557 SymX(createAdjustor) \
558 SymX(decodeDoublezh_fast) \
559 SymX(decodeFloatzh_fast) \
560 SymX(decodeDoublezu2Intzh_fast) \
561 SymX(decodeFloatzuIntzh_fast) \
564 SymX(deRefWeakzh_fast) \
565 SymX(deRefStablePtrzh_fast) \
566 SymX(dirty_MUT_VAR) \
567 SymX(divExactIntegerzh_fast) \
568 SymX(divModIntegerzh_fast) \
570 SymX(forkOnzh_fast) \
572 SymX(forkOS_createThread) \
573 SymX(freeHaskellFunctionPtr) \
574 SymX(freeStablePtr) \
575 SymX(getOrSetTypeableStore) \
576 SymX(gcdIntegerzh_fast) \
577 SymX(gcdIntegerIntzh_fast) \
578 SymX(gcdIntzh_fast) \
582 SymX(getFullProgArgv) \
588 SymX(hs_perform_gc) \
589 SymX(hs_free_stable_ptr) \
590 SymX(hs_free_fun_ptr) \
591 SymX(hs_hpc_rootModule) \
593 SymX(unpackClosurezh_fast) \
594 SymX(getApStackValzh_fast) \
595 SymX(int2Integerzh_fast) \
596 SymX(integer2Intzh_fast) \
597 SymX(integer2Wordzh_fast) \
598 SymX(isCurrentThreadBoundzh_fast) \
599 SymX(isDoubleDenormalized) \
600 SymX(isDoubleInfinite) \
602 SymX(isDoubleNegativeZero) \
603 SymX(isEmptyMVarzh_fast) \
604 SymX(isFloatDenormalized) \
605 SymX(isFloatInfinite) \
607 SymX(isFloatNegativeZero) \
608 SymX(killThreadzh_fast) \
610 SymX(insertStableSymbol) \
613 SymX(makeStablePtrzh_fast) \
614 SymX(minusIntegerzh_fast) \
615 SymX(mkApUpd0zh_fast) \
616 SymX(myThreadIdzh_fast) \
617 SymX(labelThreadzh_fast) \
618 SymX(newArrayzh_fast) \
619 SymX(newBCOzh_fast) \
620 SymX(newByteArrayzh_fast) \
621 SymX_redirect(newCAF, newDynCAF) \
622 SymX(newMVarzh_fast) \
623 SymX(newMutVarzh_fast) \
624 SymX(newTVarzh_fast) \
625 SymX(noDuplicatezh_fast) \
626 SymX(atomicModifyMutVarzh_fast) \
627 SymX(newPinnedByteArrayzh_fast) \
629 SymX(orIntegerzh_fast) \
631 SymX(performMajorGC) \
632 SymX(plusIntegerzh_fast) \
635 SymX(putMVarzh_fast) \
636 SymX(quotIntegerzh_fast) \
637 SymX(quotRemIntegerzh_fast) \
639 SymX(raiseIOzh_fast) \
640 SymX(readTVarzh_fast) \
641 SymX(remIntegerzh_fast) \
642 SymX(resetNonBlockingFd) \
647 SymX(rts_checkSchedStatus) \
650 SymX(rts_evalLazyIO) \
651 SymX(rts_evalStableIO) \
655 SymX(rts_getDouble) \
663 SymX(rts_getFunPtr) \
664 SymX(rts_getStablePtr) \
665 SymX(rts_getThreadId) \
668 SymX(rts_getWord16) \
669 SymX(rts_getWord32) \
670 SymX(rts_getWord64) \
683 SymX(rts_mkStablePtr) \
691 SymX(rtsSupportsBoundThreads) \
692 SymX(__hscore_get_saved_termios) \
693 SymX(__hscore_set_saved_termios) \
695 SymX(startupHaskell) \
696 SymX(shutdownHaskell) \
697 SymX(shutdownHaskellAndExit) \
698 SymX(stable_ptr_table) \
699 SymX(stackOverflow) \
700 SymX(stg_CAF_BLACKHOLE_info) \
701 SymX(awakenBlockedQueue) \
702 SymX(stg_CHARLIKE_closure) \
703 SymX(stg_MVAR_CLEAN_info) \
704 SymX(stg_MVAR_DIRTY_info) \
705 SymX(stg_IND_STATIC_info) \
706 SymX(stg_INTLIKE_closure) \
707 SymX(stg_MUT_ARR_PTRS_DIRTY_info) \
708 SymX(stg_MUT_ARR_PTRS_FROZEN_info) \
709 SymX(stg_MUT_ARR_PTRS_FROZEN0_info) \
710 SymX(stg_WEAK_info) \
711 SymX(stg_ap_v_info) \
712 SymX(stg_ap_f_info) \
713 SymX(stg_ap_d_info) \
714 SymX(stg_ap_l_info) \
715 SymX(stg_ap_n_info) \
716 SymX(stg_ap_p_info) \
717 SymX(stg_ap_pv_info) \
718 SymX(stg_ap_pp_info) \
719 SymX(stg_ap_ppv_info) \
720 SymX(stg_ap_ppp_info) \
721 SymX(stg_ap_pppv_info) \
722 SymX(stg_ap_pppp_info) \
723 SymX(stg_ap_ppppp_info) \
724 SymX(stg_ap_pppppp_info) \
725 SymX(stg_ap_0_fast) \
726 SymX(stg_ap_v_fast) \
727 SymX(stg_ap_f_fast) \
728 SymX(stg_ap_d_fast) \
729 SymX(stg_ap_l_fast) \
730 SymX(stg_ap_n_fast) \
731 SymX(stg_ap_p_fast) \
732 SymX(stg_ap_pv_fast) \
733 SymX(stg_ap_pp_fast) \
734 SymX(stg_ap_ppv_fast) \
735 SymX(stg_ap_ppp_fast) \
736 SymX(stg_ap_pppv_fast) \
737 SymX(stg_ap_pppp_fast) \
738 SymX(stg_ap_ppppp_fast) \
739 SymX(stg_ap_pppppp_fast) \
740 SymX(stg_ap_1_upd_info) \
741 SymX(stg_ap_2_upd_info) \
742 SymX(stg_ap_3_upd_info) \
743 SymX(stg_ap_4_upd_info) \
744 SymX(stg_ap_5_upd_info) \
745 SymX(stg_ap_6_upd_info) \
746 SymX(stg_ap_7_upd_info) \
748 SymX(stg_sel_0_upd_info) \
749 SymX(stg_sel_10_upd_info) \
750 SymX(stg_sel_11_upd_info) \
751 SymX(stg_sel_12_upd_info) \
752 SymX(stg_sel_13_upd_info) \
753 SymX(stg_sel_14_upd_info) \
754 SymX(stg_sel_15_upd_info) \
755 SymX(stg_sel_1_upd_info) \
756 SymX(stg_sel_2_upd_info) \
757 SymX(stg_sel_3_upd_info) \
758 SymX(stg_sel_4_upd_info) \
759 SymX(stg_sel_5_upd_info) \
760 SymX(stg_sel_6_upd_info) \
761 SymX(stg_sel_7_upd_info) \
762 SymX(stg_sel_8_upd_info) \
763 SymX(stg_sel_9_upd_info) \
764 SymX(stg_upd_frame_info) \
765 SymX(suspendThread) \
766 SymX(takeMVarzh_fast) \
767 SymX(timesIntegerzh_fast) \
768 SymX(tryPutMVarzh_fast) \
769 SymX(tryTakeMVarzh_fast) \
770 SymX(unblockAsyncExceptionszh_fast) \
772 SymX(unsafeThawArrayzh_fast) \
773 SymX(waitReadzh_fast) \
774 SymX(waitWritezh_fast) \
775 SymX(word2Integerzh_fast) \
776 SymX(writeTVarzh_fast) \
777 SymX(xorIntegerzh_fast) \
779 Sym(stg_interp_constr_entry) \
782 SymX(getAllocations) \
785 Sym(rts_breakpoint_io_action) \
786 Sym(rts_stop_next_breakpoint) \
787 Sym(rts_stop_on_exception) \
789 SymX(n_capabilities) \
790 RTS_USER_SIGNALS_SYMBOLS
792 #ifdef SUPPORT_LONG_LONGS
793 #define RTS_LONG_LONG_SYMS \
794 SymX(int64ToIntegerzh_fast) \
795 SymX(word64ToIntegerzh_fast)
797 #define RTS_LONG_LONG_SYMS /* nothing */
800 // 64-bit support functions in libgcc.a
801 #if defined(__GNUC__) && SIZEOF_VOID_P <= 4
802 #define RTS_LIBGCC_SYMBOLS \
812 #elif defined(ia64_HOST_ARCH)
813 #define RTS_LIBGCC_SYMBOLS \
821 #define RTS_LIBGCC_SYMBOLS
824 #if defined(darwin_HOST_OS) && defined(powerpc_HOST_ARCH)
825 // Symbols that don't have a leading underscore
826 // on Mac OS X. They have to receive special treatment,
827 // see machoInitSymbolsWithoutUnderscore()
828 #define RTS_MACHO_NOUNDERLINE_SYMBOLS \
833 /* entirely bogus claims about types of these symbols */
834 #define Sym(vvv) extern void vvv(void);
835 #if defined(__PIC__) && defined(mingw32_TARGET_OS)
836 #define SymExtern(vvv) extern void _imp__ ## vvv (void);
838 #define SymExtern(vvv) SymX(vvv)
840 #define SymX(vvv) /**/
841 #define SymX_redirect(vvv,xxx) /**/
845 RTS_POSIX_ONLY_SYMBOLS
846 RTS_MINGW_ONLY_SYMBOLS
847 RTS_CYGWIN_ONLY_SYMBOLS
848 RTS_DARWIN_ONLY_SYMBOLS
856 #ifdef LEADING_UNDERSCORE
857 #define MAYBE_LEADING_UNDERSCORE_STR(s) ("_" s)
859 #define MAYBE_LEADING_UNDERSCORE_STR(s) (s)
862 #define Sym(vvv) { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
864 #define SymX(vvv) Sym(vvv)
865 #define SymExtern(vvv) { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
866 (void*)DLL_IMPORT_DATA_REF(vvv) },
868 // SymX_redirect allows us to redirect references to one symbol to
869 // another symbol. See newCAF/newDynCAF for an example.
870 #define SymX_redirect(vvv,xxx) \
871 { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
874 static RtsSymbolVal rtsSyms[] = {
878 RTS_POSIX_ONLY_SYMBOLS
879 RTS_MINGW_ONLY_SYMBOLS
880 RTS_CYGWIN_ONLY_SYMBOLS
881 RTS_DARWIN_ONLY_SYMBOLS
884 #if defined(darwin_HOST_OS) && defined(i386_HOST_ARCH)
885 // dyld stub code contains references to this,
886 // but it should never be called because we treat
887 // lazy pointers as nonlazy.
888 { "dyld_stub_binding_helper", (void*)0xDEADBEEF },
890 { 0, 0 } /* sentinel */
895 /* -----------------------------------------------------------------------------
896 * Insert symbols into hash tables, checking for duplicates.
899 static void ghciInsertStrHashTable ( char* obj_name,
905 if (lookupHashTable(table, (StgWord)key) == NULL)
907 insertStrHashTable(table, (StgWord)key, data);
912 "GHCi runtime linker: fatal error: I found a duplicate definition for symbol\n"
914 "whilst processing object file\n"
916 "This could be caused by:\n"
917 " * Loading two different object files which export the same symbol\n"
918 " * Specifying the same object file twice on the GHCi command line\n"
919 " * An incorrect `package.conf' entry, causing some object to be\n"
921 "GHCi cannot safely continue in this situation. Exiting now. Sorry.\n"
928 /* -----------------------------------------------------------------------------
929 * initialize the object linker
933 static int linker_init_done = 0 ;
935 #if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
936 static void *dl_prog_handle;
944 /* Make initLinker idempotent, so we can call it
945 before evey relevant operation; that means we
946 don't need to initialise the linker separately */
947 if (linker_init_done == 1) { return; } else {
948 linker_init_done = 1;
951 stablehash = allocStrHashTable();
952 symhash = allocStrHashTable();
954 /* populate the symbol table with stuff from the RTS */
955 for (sym = rtsSyms; sym->lbl != NULL; sym++) {
956 ghciInsertStrHashTable("(GHCi built-in symbols)",
957 symhash, sym->lbl, sym->addr);
959 # if defined(OBJFORMAT_MACHO) && defined(powerpc_HOST_ARCH)
960 machoInitSymbolsWithoutUnderscore();
963 # if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
964 # if defined(RTLD_DEFAULT)
965 dl_prog_handle = RTLD_DEFAULT;
967 dl_prog_handle = dlopen(NULL, RTLD_LAZY);
968 # endif /* RTLD_DEFAULT */
972 /* -----------------------------------------------------------------------------
973 * Loading DLL or .so dynamic libraries
974 * -----------------------------------------------------------------------------
976 * Add a DLL from which symbols may be found. In the ELF case, just
977 * do RTLD_GLOBAL-style add, so no further messing around needs to
978 * happen in order that symbols in the loaded .so are findable --
979 * lookupSymbol() will subsequently see them by dlsym on the program's
980 * dl-handle. Returns NULL if success, otherwise ptr to an err msg.
982 * In the PEi386 case, open the DLLs and put handles to them in a
983 * linked list. When looking for a symbol, try all handles in the
984 * list. This means that we need to load even DLLs that are guaranteed
985 * to be in the ghc.exe image already, just so we can get a handle
986 * to give to loadSymbol, so that we can find the symbols. For such
987 * libraries, the LoadLibrary call should be a no-op except for returning
992 #if defined(OBJFORMAT_PEi386)
993 /* A record for storing handles into DLLs. */
998 struct _OpenedDLL* next;
1003 /* A list thereof. */
1004 static OpenedDLL* opened_dlls = NULL;
1008 addDLL( char *dll_name )
1010 # if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
1011 /* ------------------- ELF DLL loader ------------------- */
1017 hdl= dlopen(dll_name, RTLD_NOW | RTLD_GLOBAL);
1020 /* dlopen failed; return a ptr to the error msg. */
1022 if (errmsg == NULL) errmsg = "addDLL: unknown error";
1029 # elif defined(OBJFORMAT_PEi386)
1030 /* ------------------- Win32 DLL loader ------------------- */
1038 /* debugBelch("\naddDLL; dll_name = `%s'\n", dll_name); */
1040 /* See if we've already got it, and ignore if so. */
1041 for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
1042 if (0 == strcmp(o_dll->name, dll_name))
1046 /* The file name has no suffix (yet) so that we can try
1047 both foo.dll and foo.drv
1049 The documentation for LoadLibrary says:
1050 If no file name extension is specified in the lpFileName
1051 parameter, the default library extension .dll is
1052 appended. However, the file name string can include a trailing
1053 point character (.) to indicate that the module name has no
1056 buf = stgMallocBytes(strlen(dll_name) + 10, "addDLL");
1057 sprintf(buf, "%s.DLL", dll_name);
1058 instance = LoadLibrary(buf);
1059 if (instance == NULL) {
1060 sprintf(buf, "%s.DRV", dll_name); // KAA: allow loading of drivers (like winspool.drv)
1061 instance = LoadLibrary(buf);
1062 if (instance == NULL) {
1065 /* LoadLibrary failed; return a ptr to the error msg. */
1066 return "addDLL: unknown error";
1071 /* Add this DLL to the list of DLLs in which to search for symbols. */
1072 o_dll = stgMallocBytes( sizeof(OpenedDLL), "addDLL" );
1073 o_dll->name = stgMallocBytes(1+strlen(dll_name), "addDLL");
1074 strcpy(o_dll->name, dll_name);
1075 o_dll->instance = instance;
1076 o_dll->next = opened_dlls;
1077 opened_dlls = o_dll;
1081 barf("addDLL: not implemented on this platform");
1085 /* -----------------------------------------------------------------------------
1086 * insert a stable symbol in the hash table
1090 insertStableSymbol(char* obj_name, char* key, StgPtr p)
1092 ghciInsertStrHashTable(obj_name, stablehash, key, getStablePtr(p));
1096 /* -----------------------------------------------------------------------------
1097 * insert a symbol in the hash table
1100 insertSymbol(char* obj_name, char* key, void* data)
1102 ghciInsertStrHashTable(obj_name, symhash, key, data);
1105 /* -----------------------------------------------------------------------------
1106 * lookup a symbol in the hash table
1109 lookupSymbol( char *lbl )
1113 ASSERT(symhash != NULL);
1114 val = lookupStrHashTable(symhash, lbl);
1117 # if defined(OBJFORMAT_ELF)
1118 return dlsym(dl_prog_handle, lbl);
1119 # elif defined(OBJFORMAT_MACHO)
1121 /* On OS X 10.3 and later, we use dlsym instead of the old legacy
1124 HACK: On OS X, global symbols are prefixed with an underscore.
1125 However, dlsym wants us to omit the leading underscore from the
1126 symbol name. For now, we simply strip it off here (and ONLY
1129 ASSERT(lbl[0] == '_');
1130 return dlsym(dl_prog_handle, lbl+1);
1132 if(NSIsSymbolNameDefined(lbl)) {
1133 NSSymbol symbol = NSLookupAndBindSymbol(lbl);
1134 return NSAddressOfSymbol(symbol);
1138 # endif /* HAVE_DLFCN_H */
1139 # elif defined(OBJFORMAT_PEi386)
1142 for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
1143 /* debugBelch("look in %s for %s\n", o_dll->name, lbl); */
1144 if (lbl[0] == '_') {
1145 /* HACK: if the name has an initial underscore, try stripping
1146 it off & look that up first. I've yet to verify whether there's
1147 a Rule that governs whether an initial '_' *should always* be
1148 stripped off when mapping from import lib name to the DLL name.
1150 sym = GetProcAddress(o_dll->instance, (lbl+1));
1152 /*debugBelch("found %s in %s\n", lbl+1,o_dll->name);*/
1156 sym = GetProcAddress(o_dll->instance, lbl);
1158 /*debugBelch("found %s in %s\n", lbl,o_dll->name);*/
1173 __attribute((unused))
1175 lookupLocalSymbol( ObjectCode* oc, char *lbl )
1179 val = lookupStrHashTable(oc->lochash, lbl);
1189 /* -----------------------------------------------------------------------------
1190 * Debugging aid: look in GHCi's object symbol tables for symbols
1191 * within DELTA bytes of the specified address, and show their names.
1194 void ghci_enquire ( char* addr );
1196 void ghci_enquire ( char* addr )
1201 const int DELTA = 64;
1206 for (oc = objects; oc; oc = oc->next) {
1207 for (i = 0; i < oc->n_symbols; i++) {
1208 sym = oc->symbols[i];
1209 if (sym == NULL) continue;
1210 // debugBelch("enquire %p %p\n", sym, oc->lochash);
1212 if (oc->lochash != NULL) {
1213 a = lookupStrHashTable(oc->lochash, sym);
1216 a = lookupStrHashTable(symhash, sym);
1219 // debugBelch("ghci_enquire: can't find %s\n", sym);
1221 else if (addr-DELTA <= a && a <= addr+DELTA) {
1222 debugBelch("%p + %3d == `%s'\n", addr, (int)(a - addr), sym);
1229 #ifdef ia64_HOST_ARCH
1230 static unsigned int PLTSize(void);
1233 /* -----------------------------------------------------------------------------
1234 * Load an obj (populate the global symbol table, but don't resolve yet)
1236 * Returns: 1 if ok, 0 on error.
1239 loadObj( char *path )
1246 void *map_addr = NULL;
1252 /* debugBelch("loadObj %s\n", path ); */
1254 /* Check that we haven't already loaded this object.
1255 Ignore requests to load multiple times */
1259 for (o = objects; o; o = o->next) {
1260 if (0 == strcmp(o->fileName, path)) {
1262 break; /* don't need to search further */
1266 IF_DEBUG(linker, debugBelch(
1267 "GHCi runtime linker: warning: looks like you're trying to load the\n"
1268 "same object file twice:\n"
1270 "GHCi will ignore this, but be warned.\n"
1272 return 1; /* success */
1276 oc = stgMallocBytes(sizeof(ObjectCode), "loadObj(oc)");
1278 # if defined(OBJFORMAT_ELF)
1279 oc->formatName = "ELF";
1280 # elif defined(OBJFORMAT_PEi386)
1281 oc->formatName = "PEi386";
1282 # elif defined(OBJFORMAT_MACHO)
1283 oc->formatName = "Mach-O";
1286 barf("loadObj: not implemented on this platform");
1289 r = stat(path, &st);
1290 if (r == -1) { return 0; }
1292 /* sigh, strdup() isn't a POSIX function, so do it the long way */
1293 oc->fileName = stgMallocBytes( strlen(path)+1, "loadObj" );
1294 strcpy(oc->fileName, path);
1296 oc->fileSize = st.st_size;
1298 oc->sections = NULL;
1299 oc->lochash = allocStrHashTable();
1300 oc->proddables = NULL;
1302 /* chain it onto the list of objects */
1307 #define ROUND_UP(x,size) ((x + size - 1) & ~(size - 1))
1309 /* On many architectures malloc'd memory isn't executable, so we need to use mmap. */
1311 #if defined(openbsd_HOST_OS)
1312 fd = open(path, O_RDONLY, S_IRUSR);
1314 fd = open(path, O_RDONLY);
1317 barf("loadObj: can't open `%s'", path);
1319 pagesize = getpagesize();
1321 #ifdef ia64_HOST_ARCH
1322 /* The PLT needs to be right before the object */
1323 n = ROUND_UP(PLTSize(), pagesize);
1324 oc->plt = mmap(NULL, n, PROT_EXEC|PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
1325 if (oc->plt == MAP_FAILED)
1326 barf("loadObj: can't allocate PLT");
1329 map_addr = oc->plt + n;
1332 n = ROUND_UP(oc->fileSize, pagesize);
1334 /* Link objects into the lower 2Gb on x86_64. GHC assumes the
1335 * small memory model on this architecture (see gcc docs,
1338 * MAP_32BIT not available on OpenBSD/amd64
1340 #if defined(x86_64_HOST_ARCH) && defined(MAP_32BIT)
1341 #define EXTRA_MAP_FLAGS MAP_32BIT
1343 #define EXTRA_MAP_FLAGS 0
1346 /* MAP_ANONYMOUS is MAP_ANON on some systems, e.g. OpenBSD */
1347 #if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
1348 #define MAP_ANONYMOUS MAP_ANON
1351 oc->image = mmap(map_addr, n, PROT_EXEC|PROT_READ|PROT_WRITE,
1352 MAP_PRIVATE|EXTRA_MAP_FLAGS, fd, 0);
1353 if (oc->image == MAP_FAILED)
1354 barf("loadObj: can't map `%s'", path);
1358 #else /* !USE_MMAP */
1360 /* load the image into memory */
1361 f = fopen(path, "rb");
1363 barf("loadObj: can't read `%s'", path);
1365 # if defined(mingw32_HOST_OS)
1366 // TODO: We would like to use allocateExec here, but allocateExec
1367 // cannot currently allocate blocks large enough.
1368 oc->image = VirtualAlloc(NULL, oc->fileSize, MEM_RESERVE | MEM_COMMIT,
1369 PAGE_EXECUTE_READWRITE);
1370 # elif defined(darwin_HOST_OS)
1371 // In a Mach-O .o file, all sections can and will be misaligned
1372 // if the total size of the headers is not a multiple of the
1373 // desired alignment. This is fine for .o files that only serve
1374 // as input for the static linker, but it's not fine for us,
1375 // as SSE (used by gcc for floating point) and Altivec require
1376 // 16-byte alignment.
1377 // We calculate the correct alignment from the header before
1378 // reading the file, and then we misalign oc->image on purpose so
1379 // that the actual sections end up aligned again.
1380 oc->misalignment = machoGetMisalignment(f);
1381 oc->image = stgMallocBytes(oc->fileSize + oc->misalignment, "loadObj(image)");
1382 oc->image += oc->misalignment;
1384 oc->image = stgMallocBytes(oc->fileSize, "loadObj(image)");
1387 n = fread ( oc->image, 1, oc->fileSize, f );
1388 if (n != oc->fileSize)
1389 barf("loadObj: error whilst reading `%s'", path);
1392 #endif /* USE_MMAP */
1394 # if defined(OBJFORMAT_MACHO) && (defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH))
1395 r = ocAllocateSymbolExtras_MachO ( oc );
1396 if (!r) { return r; }
1397 # elif defined(OBJFORMAT_ELF) && (defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH))
1398 r = ocAllocateSymbolExtras_ELF ( oc );
1399 if (!r) { return r; }
1402 /* verify the in-memory image */
1403 # if defined(OBJFORMAT_ELF)
1404 r = ocVerifyImage_ELF ( oc );
1405 # elif defined(OBJFORMAT_PEi386)
1406 r = ocVerifyImage_PEi386 ( oc );
1407 # elif defined(OBJFORMAT_MACHO)
1408 r = ocVerifyImage_MachO ( oc );
1410 barf("loadObj: no verify method");
1412 if (!r) { return r; }
1414 /* build the symbol list for this image */
1415 # if defined(OBJFORMAT_ELF)
1416 r = ocGetNames_ELF ( oc );
1417 # elif defined(OBJFORMAT_PEi386)
1418 r = ocGetNames_PEi386 ( oc );
1419 # elif defined(OBJFORMAT_MACHO)
1420 r = ocGetNames_MachO ( oc );
1422 barf("loadObj: no getNames method");
1424 if (!r) { return r; }
1426 /* loaded, but not resolved yet */
1427 oc->status = OBJECT_LOADED;
1432 /* -----------------------------------------------------------------------------
1433 * resolve all the currently unlinked objects in memory
1435 * Returns: 1 if ok, 0 on error.
1445 for (oc = objects; oc; oc = oc->next) {
1446 if (oc->status != OBJECT_RESOLVED) {
1447 # if defined(OBJFORMAT_ELF)
1448 r = ocResolve_ELF ( oc );
1449 # elif defined(OBJFORMAT_PEi386)
1450 r = ocResolve_PEi386 ( oc );
1451 # elif defined(OBJFORMAT_MACHO)
1452 r = ocResolve_MachO ( oc );
1454 barf("resolveObjs: not implemented on this platform");
1456 if (!r) { return r; }
1457 oc->status = OBJECT_RESOLVED;
1463 /* -----------------------------------------------------------------------------
1464 * delete an object from the pool
1467 unloadObj( char *path )
1469 ObjectCode *oc, *prev;
1471 ASSERT(symhash != NULL);
1472 ASSERT(objects != NULL);
1477 for (oc = objects; oc; prev = oc, oc = oc->next) {
1478 if (!strcmp(oc->fileName,path)) {
1480 /* Remove all the mappings for the symbols within this
1485 for (i = 0; i < oc->n_symbols; i++) {
1486 if (oc->symbols[i] != NULL) {
1487 removeStrHashTable(symhash, oc->symbols[i], NULL);
1495 prev->next = oc->next;
1498 // We're going to leave this in place, in case there are
1499 // any pointers from the heap into it:
1500 // #ifdef mingw32_HOST_OS
1501 // VirtualFree(oc->image);
1503 // stgFree(oc->image);
1505 stgFree(oc->fileName);
1506 stgFree(oc->symbols);
1507 stgFree(oc->sections);
1508 /* The local hash table should have been freed at the end
1509 of the ocResolve_ call on it. */
1510 ASSERT(oc->lochash == NULL);
1516 errorBelch("unloadObj: can't find `%s' to unload", path);
1520 /* -----------------------------------------------------------------------------
1521 * Sanity checking. For each ObjectCode, maintain a list of address ranges
1522 * which may be prodded during relocation, and abort if we try and write
1523 * outside any of these.
1525 static void addProddableBlock ( ObjectCode* oc, void* start, int size )
1528 = stgMallocBytes(sizeof(ProddableBlock), "addProddableBlock");
1529 /* debugBelch("aPB %p %p %d\n", oc, start, size); */
1533 pb->next = oc->proddables;
1534 oc->proddables = pb;
1537 static void checkProddableBlock ( ObjectCode* oc, void* addr )
1540 for (pb = oc->proddables; pb != NULL; pb = pb->next) {
1541 char* s = (char*)(pb->start);
1542 char* e = s + pb->size - 1;
1543 char* a = (char*)addr;
1544 /* Assumes that the biggest fixup involves a 4-byte write. This
1545 probably needs to be changed to 8 (ie, +7) on 64-bit
1547 if (a >= s && (a+3) <= e) return;
1549 barf("checkProddableBlock: invalid fixup in runtime linker");
1552 /* -----------------------------------------------------------------------------
1553 * Section management.
1555 static void addSection ( ObjectCode* oc, SectionKind kind,
1556 void* start, void* end )
1558 Section* s = stgMallocBytes(sizeof(Section), "addSection");
1562 s->next = oc->sections;
1565 debugBelch("addSection: %p-%p (size %d), kind %d\n",
1566 start, ((char*)end)-1, end - start + 1, kind );
1571 /* --------------------------------------------------------------------------
1573 * This is about allocating a small chunk of memory for every symbol in the
1574 * object file. We make sure that the SymboLExtras are always "in range" of
1575 * limited-range PC-relative instructions on various platforms by allocating
1576 * them right next to the object code itself.
1579 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
1582 ocAllocateSymbolExtras
1584 Allocate additional space at the end of the object file image to make room
1585 for jump islands (powerpc, x86_64) and GOT entries (x86_64).
1587 PowerPC relative branch instructions have a 24 bit displacement field.
1588 As PPC code is always 4-byte-aligned, this yields a +-32MB range.
1589 If a particular imported symbol is outside this range, we have to redirect
1590 the jump to a short piece of new code that just loads the 32bit absolute
1591 address and jumps there.
1592 On x86_64, PC-relative jumps and PC-relative accesses to the GOT are limited
1595 This function just allocates space for one SymbolExtra for every
1596 undefined symbol in the object file. The code for the jump islands is
1597 filled in by makeSymbolExtra below.
1600 static int ocAllocateSymbolExtras( ObjectCode* oc, int count, int first )
1607 int misalignment = 0;
1608 #ifdef darwin_HOST_OS
1609 misalignment = oc->misalignment;
1615 // round up to the nearest 4
1616 aligned = (oc->fileSize + 3) & ~3;
1619 #ifndef linux_HOST_OS /* mremap is a linux extension */
1620 #error ocAllocateSymbolExtras doesnt want USE_MMAP to be defined
1623 pagesize = getpagesize();
1624 n = ROUND_UP( oc->fileSize, pagesize );
1625 m = ROUND_UP( aligned + sizeof (SymbolExtra) * count, pagesize );
1627 /* If we have a half-page-size file and map one page of it then
1628 * the part of the page after the size of the file remains accessible.
1629 * If, however, we map in 2 pages, the 2nd page is not accessible
1630 * and will give a "Bus Error" on access. To get around this, we check
1631 * if we need any extra pages for the jump islands and map them in
1632 * anonymously. We must check that we actually require extra pages
1633 * otherwise the attempt to mmap 0 pages of anonymous memory will
1639 /* The effect of this mremap() call is only the ensure that we have
1640 * a sufficient number of virtually contiguous pages. As returned from
1641 * mremap, the pages past the end of the file are not backed. We give
1642 * them a backing by using MAP_FIXED to map in anonymous pages.
1644 oc->image = mremap( oc->image, n, m, MREMAP_MAYMOVE );
1646 if( oc->image == MAP_FAILED )
1648 errorBelch( "Unable to mremap for Jump Islands\n" );
1652 if( mmap( oc->image + n, m - n, PROT_READ | PROT_WRITE | PROT_EXEC,
1653 MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, 0, 0 ) == MAP_FAILED )
1655 errorBelch( "Unable to mmap( MAP_FIXED ) for Jump Islands\n" );
1661 oc->image -= misalignment;
1662 oc->image = stgReallocBytes( oc->image,
1664 aligned + sizeof (SymbolExtra) * count,
1665 "ocAllocateSymbolExtras" );
1666 oc->image += misalignment;
1667 #endif /* USE_MMAP */
1669 oc->symbol_extras = (SymbolExtra *) (oc->image + aligned);
1670 memset( oc->symbol_extras, 0, sizeof (SymbolExtra) * count );
1673 oc->symbol_extras = NULL;
1675 oc->first_symbol_extra = first;
1676 oc->n_symbol_extras = count;
1681 static SymbolExtra* makeSymbolExtra( ObjectCode* oc,
1682 unsigned long symbolNumber,
1683 unsigned long target )
1687 ASSERT( symbolNumber >= oc->first_symbol_extra
1688 && symbolNumber - oc->first_symbol_extra < oc->n_symbol_extras);
1690 extra = &oc->symbol_extras[symbolNumber - oc->first_symbol_extra];
1692 #ifdef powerpc_HOST_ARCH
1693 // lis r12, hi16(target)
1694 extra->jumpIsland.lis_r12 = 0x3d80;
1695 extra->jumpIsland.hi_addr = target >> 16;
1697 // ori r12, r12, lo16(target)
1698 extra->jumpIsland.ori_r12_r12 = 0x618c;
1699 extra->jumpIsland.lo_addr = target & 0xffff;
1702 extra->jumpIsland.mtctr_r12 = 0x7d8903a6;
1705 extra->jumpIsland.bctr = 0x4e800420;
1707 #ifdef x86_64_HOST_ARCH
1709 static uint8_t jmp[] = { 0xFF, 0x25, 0xF2, 0xFF, 0xFF, 0xFF };
1710 extra->addr = target;
1711 memcpy(extra->jumpIsland, jmp, 6);
1719 /* --------------------------------------------------------------------------
1720 * PowerPC specifics (instruction cache flushing)
1721 * ------------------------------------------------------------------------*/
1723 #ifdef powerpc_TARGET_ARCH
1725 ocFlushInstructionCache
1727 Flush the data & instruction caches.
1728 Because the PPC has split data/instruction caches, we have to
1729 do that whenever we modify code at runtime.
1732 static void ocFlushInstructionCache( ObjectCode *oc )
1734 int n = (oc->fileSize + sizeof( SymbolExtra ) * oc->n_symbol_extras + 3) / 4;
1735 unsigned long *p = (unsigned long *) oc->image;
1739 __asm__ volatile ( "dcbf 0,%0\n\t"
1747 __asm__ volatile ( "sync\n\t"
1753 /* --------------------------------------------------------------------------
1754 * PEi386 specifics (Win32 targets)
1755 * ------------------------------------------------------------------------*/
1757 /* The information for this linker comes from
1758 Microsoft Portable Executable
1759 and Common Object File Format Specification
1760 revision 5.1 January 1998
1761 which SimonM says comes from the MS Developer Network CDs.
1763 It can be found there (on older CDs), but can also be found
1766 http://www.microsoft.com/hwdev/hardware/PECOFF.asp
1768 (this is Rev 6.0 from February 1999).
1770 Things move, so if that fails, try searching for it via
1772 http://www.google.com/search?q=PE+COFF+specification
1774 The ultimate reference for the PE format is the Winnt.h
1775 header file that comes with the Platform SDKs; as always,
1776 implementations will drift wrt their documentation.
1778 A good background article on the PE format is Matt Pietrek's
1779 March 1994 article in Microsoft System Journal (MSJ)
1780 (Vol.9, No. 3): "Peering Inside the PE: A Tour of the
1781 Win32 Portable Executable File Format." The info in there
1782 has recently been updated in a two part article in
1783 MSDN magazine, issues Feb and March 2002,
1784 "Inside Windows: An In-Depth Look into the Win32 Portable
1785 Executable File Format"
1787 John Levine's book "Linkers and Loaders" contains useful
1792 #if defined(OBJFORMAT_PEi386)
1796 typedef unsigned char UChar;
1797 typedef unsigned short UInt16;
1798 typedef unsigned int UInt32;
1805 UInt16 NumberOfSections;
1806 UInt32 TimeDateStamp;
1807 UInt32 PointerToSymbolTable;
1808 UInt32 NumberOfSymbols;
1809 UInt16 SizeOfOptionalHeader;
1810 UInt16 Characteristics;
1814 #define sizeof_COFF_header 20
1821 UInt32 VirtualAddress;
1822 UInt32 SizeOfRawData;
1823 UInt32 PointerToRawData;
1824 UInt32 PointerToRelocations;
1825 UInt32 PointerToLinenumbers;
1826 UInt16 NumberOfRelocations;
1827 UInt16 NumberOfLineNumbers;
1828 UInt32 Characteristics;
1832 #define sizeof_COFF_section 40
1839 UInt16 SectionNumber;
1842 UChar NumberOfAuxSymbols;
1846 #define sizeof_COFF_symbol 18
1851 UInt32 VirtualAddress;
1852 UInt32 SymbolTableIndex;
1857 #define sizeof_COFF_reloc 10
1860 /* From PE spec doc, section 3.3.2 */
1861 /* Note use of MYIMAGE_* since IMAGE_* are already defined in
1862 windows.h -- for the same purpose, but I want to know what I'm
1864 #define MYIMAGE_FILE_RELOCS_STRIPPED 0x0001
1865 #define MYIMAGE_FILE_EXECUTABLE_IMAGE 0x0002
1866 #define MYIMAGE_FILE_DLL 0x2000
1867 #define MYIMAGE_FILE_SYSTEM 0x1000
1868 #define MYIMAGE_FILE_BYTES_REVERSED_HI 0x8000
1869 #define MYIMAGE_FILE_BYTES_REVERSED_LO 0x0080
1870 #define MYIMAGE_FILE_32BIT_MACHINE 0x0100
1872 /* From PE spec doc, section 5.4.2 and 5.4.4 */
1873 #define MYIMAGE_SYM_CLASS_EXTERNAL 2
1874 #define MYIMAGE_SYM_CLASS_STATIC 3
1875 #define MYIMAGE_SYM_UNDEFINED 0
1877 /* From PE spec doc, section 4.1 */
1878 #define MYIMAGE_SCN_CNT_CODE 0x00000020
1879 #define MYIMAGE_SCN_CNT_INITIALIZED_DATA 0x00000040
1880 #define MYIMAGE_SCN_LNK_NRELOC_OVFL 0x01000000
1882 /* From PE spec doc, section 5.2.1 */
1883 #define MYIMAGE_REL_I386_DIR32 0x0006
1884 #define MYIMAGE_REL_I386_REL32 0x0014
1887 /* We use myindex to calculate array addresses, rather than
1888 simply doing the normal subscript thing. That's because
1889 some of the above structs have sizes which are not
1890 a whole number of words. GCC rounds their sizes up to a
1891 whole number of words, which means that the address calcs
1892 arising from using normal C indexing or pointer arithmetic
1893 are just plain wrong. Sigh.
1896 myindex ( int scale, void* base, int index )
1899 ((UChar*)base) + scale * index;
1904 printName ( UChar* name, UChar* strtab )
1906 if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1907 UInt32 strtab_offset = * (UInt32*)(name+4);
1908 debugBelch("%s", strtab + strtab_offset );
1911 for (i = 0; i < 8; i++) {
1912 if (name[i] == 0) break;
1913 debugBelch("%c", name[i] );
1920 copyName ( UChar* name, UChar* strtab, UChar* dst, int dstSize )
1922 if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1923 UInt32 strtab_offset = * (UInt32*)(name+4);
1924 strncpy ( dst, strtab+strtab_offset, dstSize );
1930 if (name[i] == 0) break;
1940 cstring_from_COFF_symbol_name ( UChar* name, UChar* strtab )
1943 /* If the string is longer than 8 bytes, look in the
1944 string table for it -- this will be correctly zero terminated.
1946 if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1947 UInt32 strtab_offset = * (UInt32*)(name+4);
1948 return ((UChar*)strtab) + strtab_offset;
1950 /* Otherwise, if shorter than 8 bytes, return the original,
1951 which by defn is correctly terminated.
1953 if (name[7]==0) return name;
1954 /* The annoying case: 8 bytes. Copy into a temporary
1955 (which is never freed ...)
1957 newstr = stgMallocBytes(9, "cstring_from_COFF_symbol_name");
1959 strncpy(newstr,name,8);
1965 /* Just compares the short names (first 8 chars) */
1966 static COFF_section *
1967 findPEi386SectionCalled ( ObjectCode* oc, char* name )
1971 = (COFF_header*)(oc->image);
1972 COFF_section* sectab
1974 ((UChar*)(oc->image))
1975 + sizeof_COFF_header + hdr->SizeOfOptionalHeader
1977 for (i = 0; i < hdr->NumberOfSections; i++) {
1980 COFF_section* section_i
1982 myindex ( sizeof_COFF_section, sectab, i );
1983 n1 = (UChar*) &(section_i->Name);
1985 if (n1[0]==n2[0] && n1[1]==n2[1] && n1[2]==n2[2] &&
1986 n1[3]==n2[3] && n1[4]==n2[4] && n1[5]==n2[5] &&
1987 n1[6]==n2[6] && n1[7]==n2[7])
1996 zapTrailingAtSign ( UChar* sym )
1998 # define my_isdigit(c) ((c) >= '0' && (c) <= '9')
2000 if (sym[0] == 0) return;
2002 while (sym[i] != 0) i++;
2005 while (j > 0 && my_isdigit(sym[j])) j--;
2006 if (j > 0 && sym[j] == '@' && j != i) sym[j] = 0;
2012 ocVerifyImage_PEi386 ( ObjectCode* oc )
2017 COFF_section* sectab;
2018 COFF_symbol* symtab;
2020 /* debugBelch("\nLOADING %s\n", oc->fileName); */
2021 hdr = (COFF_header*)(oc->image);
2022 sectab = (COFF_section*) (
2023 ((UChar*)(oc->image))
2024 + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2026 symtab = (COFF_symbol*) (
2027 ((UChar*)(oc->image))
2028 + hdr->PointerToSymbolTable
2030 strtab = ((UChar*)symtab)
2031 + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2033 if (hdr->Machine != 0x14c) {
2034 errorBelch("%s: Not x86 PEi386", oc->fileName);
2037 if (hdr->SizeOfOptionalHeader != 0) {
2038 errorBelch("%s: PEi386 with nonempty optional header", oc->fileName);
2041 if ( /* (hdr->Characteristics & MYIMAGE_FILE_RELOCS_STRIPPED) || */
2042 (hdr->Characteristics & MYIMAGE_FILE_EXECUTABLE_IMAGE) ||
2043 (hdr->Characteristics & MYIMAGE_FILE_DLL) ||
2044 (hdr->Characteristics & MYIMAGE_FILE_SYSTEM) ) {
2045 errorBelch("%s: Not a PEi386 object file", oc->fileName);
2048 if ( (hdr->Characteristics & MYIMAGE_FILE_BYTES_REVERSED_HI)
2049 /* || !(hdr->Characteristics & MYIMAGE_FILE_32BIT_MACHINE) */ ) {
2050 errorBelch("%s: Invalid PEi386 word size or endiannness: %d",
2052 (int)(hdr->Characteristics));
2055 /* If the string table size is way crazy, this might indicate that
2056 there are more than 64k relocations, despite claims to the
2057 contrary. Hence this test. */
2058 /* debugBelch("strtab size %d\n", * (UInt32*)strtab); */
2060 if ( (*(UInt32*)strtab) > 600000 ) {
2061 /* Note that 600k has no special significance other than being
2062 big enough to handle the almost-2MB-sized lumps that
2063 constitute HSwin32*.o. */
2064 debugBelch("PEi386 object has suspiciously large string table; > 64k relocs?");
2069 /* No further verification after this point; only debug printing. */
2071 IF_DEBUG(linker, i=1);
2072 if (i == 0) return 1;
2074 debugBelch( "sectab offset = %d\n", ((UChar*)sectab) - ((UChar*)hdr) );
2075 debugBelch( "symtab offset = %d\n", ((UChar*)symtab) - ((UChar*)hdr) );
2076 debugBelch( "strtab offset = %d\n", ((UChar*)strtab) - ((UChar*)hdr) );
2079 debugBelch( "Machine: 0x%x\n", (UInt32)(hdr->Machine) );
2080 debugBelch( "# sections: %d\n", (UInt32)(hdr->NumberOfSections) );
2081 debugBelch( "time/date: 0x%x\n", (UInt32)(hdr->TimeDateStamp) );
2082 debugBelch( "symtab offset: %d\n", (UInt32)(hdr->PointerToSymbolTable) );
2083 debugBelch( "# symbols: %d\n", (UInt32)(hdr->NumberOfSymbols) );
2084 debugBelch( "sz of opt hdr: %d\n", (UInt32)(hdr->SizeOfOptionalHeader) );
2085 debugBelch( "characteristics: 0x%x\n", (UInt32)(hdr->Characteristics) );
2087 /* Print the section table. */
2089 for (i = 0; i < hdr->NumberOfSections; i++) {
2091 COFF_section* sectab_i
2093 myindex ( sizeof_COFF_section, sectab, i );
2100 printName ( sectab_i->Name, strtab );
2110 sectab_i->VirtualSize,
2111 sectab_i->VirtualAddress,
2112 sectab_i->SizeOfRawData,
2113 sectab_i->PointerToRawData,
2114 sectab_i->NumberOfRelocations,
2115 sectab_i->PointerToRelocations,
2116 sectab_i->PointerToRawData
2118 reltab = (COFF_reloc*) (
2119 ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
2122 if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
2123 /* If the relocation field (a short) has overflowed, the
2124 * real count can be found in the first reloc entry.
2126 * See Section 4.1 (last para) of the PE spec (rev6.0).
2128 COFF_reloc* rel = (COFF_reloc*)
2129 myindex ( sizeof_COFF_reloc, reltab, 0 );
2130 noRelocs = rel->VirtualAddress;
2133 noRelocs = sectab_i->NumberOfRelocations;
2137 for (; j < noRelocs; j++) {
2139 COFF_reloc* rel = (COFF_reloc*)
2140 myindex ( sizeof_COFF_reloc, reltab, j );
2142 " type 0x%-4x vaddr 0x%-8x name `",
2144 rel->VirtualAddress );
2145 sym = (COFF_symbol*)
2146 myindex ( sizeof_COFF_symbol, symtab, rel->SymbolTableIndex );
2147 /* Hmm..mysterious looking offset - what's it for? SOF */
2148 printName ( sym->Name, strtab -10 );
2155 debugBelch("string table has size 0x%x\n", * (UInt32*)strtab );
2156 debugBelch("---START of string table---\n");
2157 for (i = 4; i < *(Int32*)strtab; i++) {
2159 debugBelch("\n"); else
2160 debugBelch("%c", strtab[i] );
2162 debugBelch("--- END of string table---\n");
2167 COFF_symbol* symtab_i;
2168 if (i >= (Int32)(hdr->NumberOfSymbols)) break;
2169 symtab_i = (COFF_symbol*)
2170 myindex ( sizeof_COFF_symbol, symtab, i );
2176 printName ( symtab_i->Name, strtab );
2185 (Int32)(symtab_i->SectionNumber),
2186 (UInt32)symtab_i->Type,
2187 (UInt32)symtab_i->StorageClass,
2188 (UInt32)symtab_i->NumberOfAuxSymbols
2190 i += symtab_i->NumberOfAuxSymbols;
2200 ocGetNames_PEi386 ( ObjectCode* oc )
2203 COFF_section* sectab;
2204 COFF_symbol* symtab;
2211 hdr = (COFF_header*)(oc->image);
2212 sectab = (COFF_section*) (
2213 ((UChar*)(oc->image))
2214 + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2216 symtab = (COFF_symbol*) (
2217 ((UChar*)(oc->image))
2218 + hdr->PointerToSymbolTable
2220 strtab = ((UChar*)(oc->image))
2221 + hdr->PointerToSymbolTable
2222 + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2224 /* Allocate space for any (local, anonymous) .bss sections. */
2226 for (i = 0; i < hdr->NumberOfSections; i++) {
2229 COFF_section* sectab_i
2231 myindex ( sizeof_COFF_section, sectab, i );
2232 if (0 != strcmp(sectab_i->Name, ".bss")) continue;
2233 /* sof 10/05: the PE spec text isn't too clear regarding what
2234 * the SizeOfRawData field is supposed to hold for object
2235 * file sections containing just uninitialized data -- for executables,
2236 * it is supposed to be zero; unclear what it's supposed to be
2237 * for object files. However, VirtualSize is guaranteed to be
2238 * zero for object files, which definitely suggests that SizeOfRawData
2239 * will be non-zero (where else would the size of this .bss section be
2240 * stored?) Looking at the COFF_section info for incoming object files,
2241 * this certainly appears to be the case.
2243 * => I suspect we've been incorrectly handling .bss sections in (relocatable)
2244 * object files up until now. This turned out to bite us with ghc-6.4.1's use
2245 * of gcc-3.4.x, which has started to emit initially-zeroed-out local 'static'
2246 * variable decls into to the .bss section. (The specific function in Q which
2247 * triggered this is libraries/base/cbits/dirUtils.c:__hscore_getFolderPath())
2249 if (sectab_i->VirtualSize == 0 && sectab_i->SizeOfRawData == 0) continue;
2250 /* This is a non-empty .bss section. Allocate zeroed space for
2251 it, and set its PointerToRawData field such that oc->image +
2252 PointerToRawData == addr_of_zeroed_space. */
2253 bss_sz = sectab_i->VirtualSize;
2254 if ( bss_sz < sectab_i->SizeOfRawData) { bss_sz = sectab_i->SizeOfRawData; }
2255 zspace = stgCallocBytes(1, bss_sz, "ocGetNames_PEi386(anonymous bss)");
2256 sectab_i->PointerToRawData = ((UChar*)zspace) - ((UChar*)(oc->image));
2257 addProddableBlock(oc, zspace, bss_sz);
2258 /* debugBelch("BSS anon section at 0x%x\n", zspace); */
2261 /* Copy section information into the ObjectCode. */
2263 for (i = 0; i < hdr->NumberOfSections; i++) {
2269 = SECTIONKIND_OTHER;
2270 COFF_section* sectab_i
2272 myindex ( sizeof_COFF_section, sectab, i );
2273 IF_DEBUG(linker, debugBelch("section name = %s\n", sectab_i->Name ));
2276 /* I'm sure this is the Right Way to do it. However, the
2277 alternative of testing the sectab_i->Name field seems to
2278 work ok with Cygwin.
2280 if (sectab_i->Characteristics & MYIMAGE_SCN_CNT_CODE ||
2281 sectab_i->Characteristics & MYIMAGE_SCN_CNT_INITIALIZED_DATA)
2282 kind = SECTIONKIND_CODE_OR_RODATA;
2285 if (0==strcmp(".text",sectab_i->Name) ||
2286 0==strcmp(".rdata",sectab_i->Name)||
2287 0==strcmp(".rodata",sectab_i->Name))
2288 kind = SECTIONKIND_CODE_OR_RODATA;
2289 if (0==strcmp(".data",sectab_i->Name) ||
2290 0==strcmp(".bss",sectab_i->Name))
2291 kind = SECTIONKIND_RWDATA;
2293 ASSERT(sectab_i->SizeOfRawData == 0 || sectab_i->VirtualSize == 0);
2294 sz = sectab_i->SizeOfRawData;
2295 if (sz < sectab_i->VirtualSize) sz = sectab_i->VirtualSize;
2297 start = ((UChar*)(oc->image)) + sectab_i->PointerToRawData;
2298 end = start + sz - 1;
2300 if (kind == SECTIONKIND_OTHER
2301 /* Ignore sections called which contain stabs debugging
2303 && 0 != strcmp(".stab", sectab_i->Name)
2304 && 0 != strcmp(".stabstr", sectab_i->Name)
2305 /* ignore constructor section for now */
2306 && 0 != strcmp(".ctors", sectab_i->Name)
2307 /* ignore section generated from .ident */
2308 && 0!= strcmp("/4", sectab_i->Name)
2309 /* ignore unknown section that appeared in gcc 3.4.5(?) */
2310 && 0!= strcmp(".reloc", sectab_i->Name)
2312 errorBelch("Unknown PEi386 section name `%s' (while processing: %s)", sectab_i->Name, oc->fileName);
2316 if (kind != SECTIONKIND_OTHER && end >= start) {
2317 addSection(oc, kind, start, end);
2318 addProddableBlock(oc, start, end - start + 1);
2322 /* Copy exported symbols into the ObjectCode. */
2324 oc->n_symbols = hdr->NumberOfSymbols;
2325 oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
2326 "ocGetNames_PEi386(oc->symbols)");
2327 /* Call me paranoid; I don't care. */
2328 for (i = 0; i < oc->n_symbols; i++)
2329 oc->symbols[i] = NULL;
2333 COFF_symbol* symtab_i;
2334 if (i >= (Int32)(hdr->NumberOfSymbols)) break;
2335 symtab_i = (COFF_symbol*)
2336 myindex ( sizeof_COFF_symbol, symtab, i );
2340 if (symtab_i->StorageClass == MYIMAGE_SYM_CLASS_EXTERNAL
2341 && symtab_i->SectionNumber != MYIMAGE_SYM_UNDEFINED) {
2342 /* This symbol is global and defined, viz, exported */
2343 /* for MYIMAGE_SYMCLASS_EXTERNAL
2344 && !MYIMAGE_SYM_UNDEFINED,
2345 the address of the symbol is:
2346 address of relevant section + offset in section
2348 COFF_section* sectabent
2349 = (COFF_section*) myindex ( sizeof_COFF_section,
2351 symtab_i->SectionNumber-1 );
2352 addr = ((UChar*)(oc->image))
2353 + (sectabent->PointerToRawData
2357 if (symtab_i->SectionNumber == MYIMAGE_SYM_UNDEFINED
2358 && symtab_i->Value > 0) {
2359 /* This symbol isn't in any section at all, ie, global bss.
2360 Allocate zeroed space for it. */
2361 addr = stgCallocBytes(1, symtab_i->Value,
2362 "ocGetNames_PEi386(non-anonymous bss)");
2363 addSection(oc, SECTIONKIND_RWDATA, addr,
2364 ((UChar*)addr) + symtab_i->Value - 1);
2365 addProddableBlock(oc, addr, symtab_i->Value);
2366 /* debugBelch("BSS section at 0x%x\n", addr); */
2369 if (addr != NULL ) {
2370 sname = cstring_from_COFF_symbol_name ( symtab_i->Name, strtab );
2371 /* debugBelch("addSymbol %p `%s \n", addr,sname); */
2372 IF_DEBUG(linker, debugBelch("addSymbol %p `%s'\n", addr,sname);)
2373 ASSERT(i >= 0 && i < oc->n_symbols);
2374 /* cstring_from_COFF_symbol_name always succeeds. */
2375 oc->symbols[i] = sname;
2376 ghciInsertStrHashTable(oc->fileName, symhash, sname, addr);
2380 "IGNORING symbol %d\n"
2384 printName ( symtab_i->Name, strtab );
2393 (Int32)(symtab_i->SectionNumber),
2394 (UInt32)symtab_i->Type,
2395 (UInt32)symtab_i->StorageClass,
2396 (UInt32)symtab_i->NumberOfAuxSymbols
2401 i += symtab_i->NumberOfAuxSymbols;
2410 ocResolve_PEi386 ( ObjectCode* oc )
2413 COFF_section* sectab;
2414 COFF_symbol* symtab;
2424 /* ToDo: should be variable-sized? But is at least safe in the
2425 sense of buffer-overrun-proof. */
2427 /* debugBelch("resolving for %s\n", oc->fileName); */
2429 hdr = (COFF_header*)(oc->image);
2430 sectab = (COFF_section*) (
2431 ((UChar*)(oc->image))
2432 + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2434 symtab = (COFF_symbol*) (
2435 ((UChar*)(oc->image))
2436 + hdr->PointerToSymbolTable
2438 strtab = ((UChar*)(oc->image))
2439 + hdr->PointerToSymbolTable
2440 + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2442 for (i = 0; i < hdr->NumberOfSections; i++) {
2443 COFF_section* sectab_i
2445 myindex ( sizeof_COFF_section, sectab, i );
2448 ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
2451 /* Ignore sections called which contain stabs debugging
2453 if (0 == strcmp(".stab", sectab_i->Name)
2454 || 0 == strcmp(".stabstr", sectab_i->Name)
2455 || 0 == strcmp(".ctors", sectab_i->Name))
2458 if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
2459 /* If the relocation field (a short) has overflowed, the
2460 * real count can be found in the first reloc entry.
2462 * See Section 4.1 (last para) of the PE spec (rev6.0).
2464 * Nov2003 update: the GNU linker still doesn't correctly
2465 * handle the generation of relocatable object files with
2466 * overflown relocations. Hence the output to warn of potential
2469 COFF_reloc* rel = (COFF_reloc*)
2470 myindex ( sizeof_COFF_reloc, reltab, 0 );
2471 noRelocs = rel->VirtualAddress;
2473 /* 10/05: we now assume (and check for) a GNU ld that is capable
2474 * of handling object files with (>2^16) of relocs.
2477 debugBelch("WARNING: Overflown relocation field (# relocs found: %u)\n",
2482 noRelocs = sectab_i->NumberOfRelocations;
2487 for (; j < noRelocs; j++) {
2489 COFF_reloc* reltab_j
2491 myindex ( sizeof_COFF_reloc, reltab, j );
2493 /* the location to patch */
2495 ((UChar*)(oc->image))
2496 + (sectab_i->PointerToRawData
2497 + reltab_j->VirtualAddress
2498 - sectab_i->VirtualAddress )
2500 /* the existing contents of pP */
2502 /* the symbol to connect to */
2503 sym = (COFF_symbol*)
2504 myindex ( sizeof_COFF_symbol,
2505 symtab, reltab_j->SymbolTableIndex );
2508 "reloc sec %2d num %3d: type 0x%-4x "
2509 "vaddr 0x%-8x name `",
2511 (UInt32)reltab_j->Type,
2512 reltab_j->VirtualAddress );
2513 printName ( sym->Name, strtab );
2514 debugBelch("'\n" ));
2516 if (sym->StorageClass == MYIMAGE_SYM_CLASS_STATIC) {
2517 COFF_section* section_sym
2518 = findPEi386SectionCalled ( oc, sym->Name );
2520 errorBelch("%s: can't find section `%s'", oc->fileName, sym->Name);
2523 S = ((UInt32)(oc->image))
2524 + (section_sym->PointerToRawData
2527 copyName ( sym->Name, strtab, symbol, 1000-1 );
2528 S = (UInt32) lookupLocalSymbol( oc, symbol );
2529 if ((void*)S != NULL) goto foundit;
2530 S = (UInt32) lookupSymbol( symbol );
2531 if ((void*)S != NULL) goto foundit;
2532 zapTrailingAtSign ( symbol );
2533 S = (UInt32) lookupLocalSymbol( oc, symbol );
2534 if ((void*)S != NULL) goto foundit;
2535 S = (UInt32) lookupSymbol( symbol );
2536 if ((void*)S != NULL) goto foundit;
2537 /* Newline first because the interactive linker has printed "linking..." */
2538 errorBelch("\n%s: unknown symbol `%s'", oc->fileName, symbol);
2542 checkProddableBlock(oc, pP);
2543 switch (reltab_j->Type) {
2544 case MYIMAGE_REL_I386_DIR32:
2547 case MYIMAGE_REL_I386_REL32:
2548 /* Tricky. We have to insert a displacement at
2549 pP which, when added to the PC for the _next_
2550 insn, gives the address of the target (S).
2551 Problem is to know the address of the next insn
2552 when we only know pP. We assume that this
2553 literal field is always the last in the insn,
2554 so that the address of the next insn is pP+4
2555 -- hence the constant 4.
2556 Also I don't know if A should be added, but so
2557 far it has always been zero.
2559 SOF 05/2005: 'A' (old contents of *pP) have been observed
2560 to contain values other than zero (the 'wx' object file
2561 that came with wxhaskell-0.9.4; dunno how it was compiled..).
2562 So, add displacement to old value instead of asserting
2563 A to be zero. Fixes wxhaskell-related crashes, and no other
2564 ill effects have been observed.
2566 Update: the reason why we're seeing these more elaborate
2567 relocations is due to a switch in how the NCG compiles SRTs
2568 and offsets to them from info tables. SRTs live in .(ro)data,
2569 while info tables live in .text, causing GAS to emit REL32/DISP32
2570 relocations with non-zero values. Adding the displacement is
2571 the right thing to do.
2573 *pP = S - ((UInt32)pP) - 4 + A;
2576 debugBelch("%s: unhandled PEi386 relocation type %d",
2577 oc->fileName, reltab_j->Type);
2584 IF_DEBUG(linker, debugBelch("completed %s", oc->fileName));
2588 #endif /* defined(OBJFORMAT_PEi386) */
2591 /* --------------------------------------------------------------------------
2593 * ------------------------------------------------------------------------*/
2595 #if defined(OBJFORMAT_ELF)
2600 #if defined(sparc_HOST_ARCH)
2601 # define ELF_TARGET_SPARC /* Used inside <elf.h> */
2602 #elif defined(i386_HOST_ARCH)
2603 # define ELF_TARGET_386 /* Used inside <elf.h> */
2604 #elif defined(x86_64_HOST_ARCH)
2605 # define ELF_TARGET_X64_64
2607 #elif defined (ia64_HOST_ARCH)
2608 # define ELF_TARGET_IA64 /* Used inside <elf.h> */
2610 # define ELF_FUNCTION_DESC /* calling convention uses function descriptors */
2611 # define ELF_NEED_GOT /* needs Global Offset Table */
2612 # define ELF_NEED_PLT /* needs Procedure Linkage Tables */
2615 #if !defined(openbsd_HOST_OS)
2618 /* openbsd elf has things in different places, with diff names */
2619 # include <elf_abi.h>
2620 # include <machine/reloc.h>
2621 # define R_386_32 RELOC_32
2622 # define R_386_PC32 RELOC_PC32
2625 /* If elf.h doesn't define it */
2626 # ifndef R_X86_64_PC64
2627 # define R_X86_64_PC64 24
2631 * Define a set of types which can be used for both ELF32 and ELF64
2635 #define ELFCLASS ELFCLASS64
2636 #define Elf_Addr Elf64_Addr
2637 #define Elf_Word Elf64_Word
2638 #define Elf_Sword Elf64_Sword
2639 #define Elf_Ehdr Elf64_Ehdr
2640 #define Elf_Phdr Elf64_Phdr
2641 #define Elf_Shdr Elf64_Shdr
2642 #define Elf_Sym Elf64_Sym
2643 #define Elf_Rel Elf64_Rel
2644 #define Elf_Rela Elf64_Rela
2645 #define ELF_ST_TYPE ELF64_ST_TYPE
2646 #define ELF_ST_BIND ELF64_ST_BIND
2647 #define ELF_R_TYPE ELF64_R_TYPE
2648 #define ELF_R_SYM ELF64_R_SYM
2650 #define ELFCLASS ELFCLASS32
2651 #define Elf_Addr Elf32_Addr
2652 #define Elf_Word Elf32_Word
2653 #define Elf_Sword Elf32_Sword
2654 #define Elf_Ehdr Elf32_Ehdr
2655 #define Elf_Phdr Elf32_Phdr
2656 #define Elf_Shdr Elf32_Shdr
2657 #define Elf_Sym Elf32_Sym
2658 #define Elf_Rel Elf32_Rel
2659 #define Elf_Rela Elf32_Rela
2661 #define ELF_ST_TYPE ELF32_ST_TYPE
2664 #define ELF_ST_BIND ELF32_ST_BIND
2667 #define ELF_R_TYPE ELF32_R_TYPE
2670 #define ELF_R_SYM ELF32_R_SYM
2676 * Functions to allocate entries in dynamic sections. Currently we simply
2677 * preallocate a large number, and we don't check if a entry for the given
2678 * target already exists (a linear search is too slow). Ideally these
2679 * entries would be associated with symbols.
2682 /* These sizes sufficient to load HSbase + HShaskell98 + a few modules */
2683 #define GOT_SIZE 0x20000
2684 #define FUNCTION_TABLE_SIZE 0x10000
2685 #define PLT_SIZE 0x08000
2688 static Elf_Addr got[GOT_SIZE];
2689 static unsigned int gotIndex;
2690 static Elf_Addr gp_val = (Elf_Addr)got;
2693 allocateGOTEntry(Elf_Addr target)
2697 if (gotIndex >= GOT_SIZE)
2698 barf("Global offset table overflow");
2700 entry = &got[gotIndex++];
2702 return (Elf_Addr)entry;
2706 #ifdef ELF_FUNCTION_DESC
2712 static FunctionDesc functionTable[FUNCTION_TABLE_SIZE];
2713 static unsigned int functionTableIndex;
2716 allocateFunctionDesc(Elf_Addr target)
2718 FunctionDesc *entry;
2720 if (functionTableIndex >= FUNCTION_TABLE_SIZE)
2721 barf("Function table overflow");
2723 entry = &functionTable[functionTableIndex++];
2725 entry->gp = (Elf_Addr)gp_val;
2726 return (Elf_Addr)entry;
2730 copyFunctionDesc(Elf_Addr target)
2732 FunctionDesc *olddesc = (FunctionDesc *)target;
2733 FunctionDesc *newdesc;
2735 newdesc = (FunctionDesc *)allocateFunctionDesc(olddesc->ip);
2736 newdesc->gp = olddesc->gp;
2737 return (Elf_Addr)newdesc;
2742 #ifdef ia64_HOST_ARCH
2743 static void ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value);
2744 static void ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc);
2746 static unsigned char plt_code[] =
2748 /* taken from binutils bfd/elfxx-ia64.c */
2749 0x0b, 0x78, 0x00, 0x02, 0x00, 0x24, /* [MMI] addl r15=0,r1;; */
2750 0x00, 0x41, 0x3c, 0x30, 0x28, 0xc0, /* ld8 r16=[r15],8 */
2751 0x01, 0x08, 0x00, 0x84, /* mov r14=r1;; */
2752 0x11, 0x08, 0x00, 0x1e, 0x18, 0x10, /* [MIB] ld8 r1=[r15] */
2753 0x60, 0x80, 0x04, 0x80, 0x03, 0x00, /* mov b6=r16 */
2754 0x60, 0x00, 0x80, 0x00 /* br.few b6;; */
2757 /* If we can't get to the function descriptor via gp, take a local copy of it */
2758 #define PLT_RELOC(code, target) { \
2759 Elf64_Sxword rel_value = target - gp_val; \
2760 if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff)) \
2761 ia64_reloc_gprel22((Elf_Addr)code, copyFunctionDesc(target)); \
2763 ia64_reloc_gprel22((Elf_Addr)code, target); \
2768 unsigned char code[sizeof(plt_code)];
2772 allocatePLTEntry(Elf_Addr target, ObjectCode *oc)
2774 PLTEntry *plt = (PLTEntry *)oc->plt;
2777 if (oc->pltIndex >= PLT_SIZE)
2778 barf("Procedure table overflow");
2780 entry = &plt[oc->pltIndex++];
2781 memcpy(entry->code, plt_code, sizeof(entry->code));
2782 PLT_RELOC(entry->code, target);
2783 return (Elf_Addr)entry;
2789 return (PLT_SIZE * sizeof(PLTEntry));
2795 * Generic ELF functions
2799 findElfSection ( void* objImage, Elf_Word sh_type )
2801 char* ehdrC = (char*)objImage;
2802 Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2803 Elf_Shdr* shdr = (Elf_Shdr*)(ehdrC + ehdr->e_shoff);
2804 char* sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
2808 for (i = 0; i < ehdr->e_shnum; i++) {
2809 if (shdr[i].sh_type == sh_type
2810 /* Ignore the section header's string table. */
2811 && i != ehdr->e_shstrndx
2812 /* Ignore string tables named .stabstr, as they contain
2814 && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
2816 ptr = ehdrC + shdr[i].sh_offset;
2823 #if defined(ia64_HOST_ARCH)
2825 findElfSegment ( void* objImage, Elf_Addr vaddr )
2827 char* ehdrC = (char*)objImage;
2828 Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2829 Elf_Phdr* phdr = (Elf_Phdr*)(ehdrC + ehdr->e_phoff);
2830 Elf_Addr segaddr = 0;
2833 for (i = 0; i < ehdr->e_phnum; i++) {
2834 segaddr = phdr[i].p_vaddr;
2835 if ((vaddr >= segaddr) && (vaddr < segaddr + phdr[i].p_memsz))
2843 ocVerifyImage_ELF ( ObjectCode* oc )
2847 int i, j, nent, nstrtab, nsymtabs;
2851 char* ehdrC = (char*)(oc->image);
2852 Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2854 if (ehdr->e_ident[EI_MAG0] != ELFMAG0 ||
2855 ehdr->e_ident[EI_MAG1] != ELFMAG1 ||
2856 ehdr->e_ident[EI_MAG2] != ELFMAG2 ||
2857 ehdr->e_ident[EI_MAG3] != ELFMAG3) {
2858 errorBelch("%s: not an ELF object", oc->fileName);
2862 if (ehdr->e_ident[EI_CLASS] != ELFCLASS) {
2863 errorBelch("%s: unsupported ELF format", oc->fileName);
2867 if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) {
2868 IF_DEBUG(linker,debugBelch( "Is little-endian\n" ));
2870 if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) {
2871 IF_DEBUG(linker,debugBelch( "Is big-endian\n" ));
2873 errorBelch("%s: unknown endiannness", oc->fileName);
2877 if (ehdr->e_type != ET_REL) {
2878 errorBelch("%s: not a relocatable object (.o) file", oc->fileName);
2881 IF_DEBUG(linker, debugBelch( "Is a relocatable object (.o) file\n" ));
2883 IF_DEBUG(linker,debugBelch( "Architecture is " ));
2884 switch (ehdr->e_machine) {
2885 case EM_386: IF_DEBUG(linker,debugBelch( "x86" )); break;
2886 #ifdef EM_SPARC32PLUS
2887 case EM_SPARC32PLUS:
2889 case EM_SPARC: IF_DEBUG(linker,debugBelch( "sparc" )); break;
2891 case EM_IA_64: IF_DEBUG(linker,debugBelch( "ia64" )); break;
2893 case EM_PPC: IF_DEBUG(linker,debugBelch( "powerpc32" )); break;
2895 case EM_X86_64: IF_DEBUG(linker,debugBelch( "x86_64" )); break;
2896 #elif defined(EM_AMD64)
2897 case EM_AMD64: IF_DEBUG(linker,debugBelch( "amd64" )); break;
2899 default: IF_DEBUG(linker,debugBelch( "unknown" ));
2900 errorBelch("%s: unknown architecture (e_machine == %d)"
2901 , oc->fileName, ehdr->e_machine);
2905 IF_DEBUG(linker,debugBelch(
2906 "\nSection header table: start %ld, n_entries %d, ent_size %d\n",
2907 (long)ehdr->e_shoff, ehdr->e_shnum, ehdr->e_shentsize ));
2909 ASSERT (ehdr->e_shentsize == sizeof(Elf_Shdr));
2911 shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
2913 if (ehdr->e_shstrndx == SHN_UNDEF) {
2914 errorBelch("%s: no section header string table", oc->fileName);
2917 IF_DEBUG(linker,debugBelch( "Section header string table is section %d\n",
2919 sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
2922 for (i = 0; i < ehdr->e_shnum; i++) {
2923 IF_DEBUG(linker,debugBelch("%2d: ", i ));
2924 IF_DEBUG(linker,debugBelch("type=%2d ", (int)shdr[i].sh_type ));
2925 IF_DEBUG(linker,debugBelch("size=%4d ", (int)shdr[i].sh_size ));
2926 IF_DEBUG(linker,debugBelch("offs=%4d ", (int)shdr[i].sh_offset ));
2927 IF_DEBUG(linker,debugBelch(" (%p .. %p) ",
2928 ehdrC + shdr[i].sh_offset,
2929 ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1));
2931 if (shdr[i].sh_type == SHT_REL) {
2932 IF_DEBUG(linker,debugBelch("Rel " ));
2933 } else if (shdr[i].sh_type == SHT_RELA) {
2934 IF_DEBUG(linker,debugBelch("RelA " ));
2936 IF_DEBUG(linker,debugBelch(" "));
2939 IF_DEBUG(linker,debugBelch("sname=%s\n", sh_strtab + shdr[i].sh_name ));
2943 IF_DEBUG(linker,debugBelch( "\nString tables" ));
2946 for (i = 0; i < ehdr->e_shnum; i++) {
2947 if (shdr[i].sh_type == SHT_STRTAB
2948 /* Ignore the section header's string table. */
2949 && i != ehdr->e_shstrndx
2950 /* Ignore string tables named .stabstr, as they contain
2952 && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
2954 IF_DEBUG(linker,debugBelch(" section %d is a normal string table", i ));
2955 strtab = ehdrC + shdr[i].sh_offset;
2960 errorBelch("%s: no string tables, or too many", oc->fileName);
2965 IF_DEBUG(linker,debugBelch( "\nSymbol tables" ));
2966 for (i = 0; i < ehdr->e_shnum; i++) {
2967 if (shdr[i].sh_type != SHT_SYMTAB) continue;
2968 IF_DEBUG(linker,debugBelch( "section %d is a symbol table\n", i ));
2970 stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
2971 nent = shdr[i].sh_size / sizeof(Elf_Sym);
2972 IF_DEBUG(linker,debugBelch( " number of entries is apparently %d (%ld rem)\n",
2974 (long)shdr[i].sh_size % sizeof(Elf_Sym)
2976 if (0 != shdr[i].sh_size % sizeof(Elf_Sym)) {
2977 errorBelch("%s: non-integral number of symbol table entries", oc->fileName);
2980 for (j = 0; j < nent; j++) {
2981 IF_DEBUG(linker,debugBelch(" %2d ", j ));
2982 IF_DEBUG(linker,debugBelch(" sec=%-5d size=%-3d val=%5p ",
2983 (int)stab[j].st_shndx,
2984 (int)stab[j].st_size,
2985 (char*)stab[j].st_value ));
2987 IF_DEBUG(linker,debugBelch("type=" ));
2988 switch (ELF_ST_TYPE(stab[j].st_info)) {
2989 case STT_NOTYPE: IF_DEBUG(linker,debugBelch("notype " )); break;
2990 case STT_OBJECT: IF_DEBUG(linker,debugBelch("object " )); break;
2991 case STT_FUNC : IF_DEBUG(linker,debugBelch("func " )); break;
2992 case STT_SECTION: IF_DEBUG(linker,debugBelch("section" )); break;
2993 case STT_FILE: IF_DEBUG(linker,debugBelch("file " )); break;
2994 default: IF_DEBUG(linker,debugBelch("? " )); break;
2996 IF_DEBUG(linker,debugBelch(" " ));
2998 IF_DEBUG(linker,debugBelch("bind=" ));
2999 switch (ELF_ST_BIND(stab[j].st_info)) {
3000 case STB_LOCAL : IF_DEBUG(linker,debugBelch("local " )); break;
3001 case STB_GLOBAL: IF_DEBUG(linker,debugBelch("global" )); break;
3002 case STB_WEAK : IF_DEBUG(linker,debugBelch("weak " )); break;
3003 default: IF_DEBUG(linker,debugBelch("? " )); break;
3005 IF_DEBUG(linker,debugBelch(" " ));
3007 IF_DEBUG(linker,debugBelch("name=%s\n", strtab + stab[j].st_name ));
3011 if (nsymtabs == 0) {
3012 errorBelch("%s: didn't find any symbol tables", oc->fileName);
3019 static int getSectionKind_ELF( Elf_Shdr *hdr, int *is_bss )
3023 if (hdr->sh_type == SHT_PROGBITS
3024 && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_EXECINSTR)) {
3025 /* .text-style section */
3026 return SECTIONKIND_CODE_OR_RODATA;
3029 if (hdr->sh_type == SHT_PROGBITS
3030 && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
3031 /* .data-style section */
3032 return SECTIONKIND_RWDATA;
3035 if (hdr->sh_type == SHT_PROGBITS
3036 && (hdr->sh_flags & SHF_ALLOC) && !(hdr->sh_flags & SHF_WRITE)) {
3037 /* .rodata-style section */
3038 return SECTIONKIND_CODE_OR_RODATA;
3041 if (hdr->sh_type == SHT_NOBITS
3042 && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
3043 /* .bss-style section */
3045 return SECTIONKIND_RWDATA;
3048 return SECTIONKIND_OTHER;
3053 ocGetNames_ELF ( ObjectCode* oc )
3058 char* ehdrC = (char*)(oc->image);
3059 Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
3060 char* strtab = findElfSection ( ehdrC, SHT_STRTAB );
3061 Elf_Shdr* shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
3063 ASSERT(symhash != NULL);
3066 errorBelch("%s: no strtab", oc->fileName);
3071 for (i = 0; i < ehdr->e_shnum; i++) {
3072 /* Figure out what kind of section it is. Logic derived from
3073 Figure 1.14 ("Special Sections") of the ELF document
3074 ("Portable Formats Specification, Version 1.1"). */
3076 SectionKind kind = getSectionKind_ELF(&shdr[i], &is_bss);
3078 if (is_bss && shdr[i].sh_size > 0) {
3079 /* This is a non-empty .bss section. Allocate zeroed space for
3080 it, and set its .sh_offset field such that
3081 ehdrC + .sh_offset == addr_of_zeroed_space. */
3082 char* zspace = stgCallocBytes(1, shdr[i].sh_size,
3083 "ocGetNames_ELF(BSS)");
3084 shdr[i].sh_offset = ((char*)zspace) - ((char*)ehdrC);
3086 debugBelch("BSS section at 0x%x, size %d\n",
3087 zspace, shdr[i].sh_size);
3091 /* fill in the section info */
3092 if (kind != SECTIONKIND_OTHER && shdr[i].sh_size > 0) {
3093 addProddableBlock(oc, ehdrC + shdr[i].sh_offset, shdr[i].sh_size);
3094 addSection(oc, kind, ehdrC + shdr[i].sh_offset,
3095 ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1);
3098 if (shdr[i].sh_type != SHT_SYMTAB) continue;
3100 /* copy stuff into this module's object symbol table */
3101 stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
3102 nent = shdr[i].sh_size / sizeof(Elf_Sym);
3104 oc->n_symbols = nent;
3105 oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
3106 "ocGetNames_ELF(oc->symbols)");
3108 for (j = 0; j < nent; j++) {
3110 char isLocal = FALSE; /* avoids uninit-var warning */
3112 char* nm = strtab + stab[j].st_name;
3113 int secno = stab[j].st_shndx;
3115 /* Figure out if we want to add it; if so, set ad to its
3116 address. Otherwise leave ad == NULL. */
3118 if (secno == SHN_COMMON) {
3120 ad = stgCallocBytes(1, stab[j].st_size, "ocGetNames_ELF(COMMON)");
3122 debugBelch("COMMON symbol, size %d name %s\n",
3123 stab[j].st_size, nm);
3125 /* Pointless to do addProddableBlock() for this area,
3126 since the linker should never poke around in it. */
3129 if ( ( ELF_ST_BIND(stab[j].st_info)==STB_GLOBAL
3130 || ELF_ST_BIND(stab[j].st_info)==STB_LOCAL
3132 /* and not an undefined symbol */
3133 && stab[j].st_shndx != SHN_UNDEF
3134 /* and not in a "special section" */
3135 && stab[j].st_shndx < SHN_LORESERVE
3137 /* and it's a not a section or string table or anything silly */
3138 ( ELF_ST_TYPE(stab[j].st_info)==STT_FUNC ||
3139 ELF_ST_TYPE(stab[j].st_info)==STT_OBJECT ||
3140 ELF_ST_TYPE(stab[j].st_info)==STT_NOTYPE
3143 /* Section 0 is the undefined section, hence > and not >=. */
3144 ASSERT(secno > 0 && secno < ehdr->e_shnum);
3146 if (shdr[secno].sh_type == SHT_NOBITS) {
3147 debugBelch(" BSS symbol, size %d off %d name %s\n",
3148 stab[j].st_size, stab[j].st_value, nm);
3151 ad = ehdrC + shdr[ secno ].sh_offset + stab[j].st_value;
3152 if (ELF_ST_BIND(stab[j].st_info)==STB_LOCAL) {
3155 #ifdef ELF_FUNCTION_DESC
3156 /* dlsym() and the initialisation table both give us function
3157 * descriptors, so to be consistent we store function descriptors
3158 * in the symbol table */
3159 if (ELF_ST_TYPE(stab[j].st_info) == STT_FUNC)
3160 ad = (char *)allocateFunctionDesc((Elf_Addr)ad);
3162 IF_DEBUG(linker,debugBelch( "addOTabName(GLOB): %10p %s %s",
3163 ad, oc->fileName, nm ));
3168 /* And the decision is ... */
3172 oc->symbols[j] = nm;
3175 /* Ignore entirely. */
3177 ghciInsertStrHashTable(oc->fileName, symhash, nm, ad);
3181 IF_DEBUG(linker,debugBelch( "skipping `%s'\n",
3182 strtab + stab[j].st_name ));
3185 "skipping bind = %d, type = %d, shndx = %d `%s'\n",
3186 (int)ELF_ST_BIND(stab[j].st_info),
3187 (int)ELF_ST_TYPE(stab[j].st_info),
3188 (int)stab[j].st_shndx,
3189 strtab + stab[j].st_name
3192 oc->symbols[j] = NULL;
3201 /* Do ELF relocations which lack an explicit addend. All x86-linux
3202 relocations appear to be of this form. */
3204 do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
3205 Elf_Shdr* shdr, int shnum,
3206 Elf_Sym* stab, char* strtab )
3211 Elf_Rel* rtab = (Elf_Rel*) (ehdrC + shdr[shnum].sh_offset);
3212 int nent = shdr[shnum].sh_size / sizeof(Elf_Rel);
3213 int target_shndx = shdr[shnum].sh_info;
3214 int symtab_shndx = shdr[shnum].sh_link;
3216 stab = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
3217 targ = (Elf_Word*)(ehdrC + shdr[ target_shndx ].sh_offset);
3218 IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
3219 target_shndx, symtab_shndx ));
3221 /* Skip sections that we're not interested in. */
3224 SectionKind kind = getSectionKind_ELF(&shdr[target_shndx], &is_bss);
3225 if (kind == SECTIONKIND_OTHER) {
3226 IF_DEBUG(linker,debugBelch( "skipping (target section not loaded)"));
3231 for (j = 0; j < nent; j++) {
3232 Elf_Addr offset = rtab[j].r_offset;
3233 Elf_Addr info = rtab[j].r_info;
3235 Elf_Addr P = ((Elf_Addr)targ) + offset;
3236 Elf_Word* pP = (Elf_Word*)P;
3241 StgStablePtr stablePtr;
3244 IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p)",
3245 j, (void*)offset, (void*)info ));
3247 IF_DEBUG(linker,debugBelch( " ZERO" ));
3250 Elf_Sym sym = stab[ELF_R_SYM(info)];
3251 /* First see if it is a local symbol. */
3252 if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
3253 /* Yes, so we can get the address directly from the ELF symbol
3255 symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
3257 (ehdrC + shdr[ sym.st_shndx ].sh_offset
3258 + stab[ELF_R_SYM(info)].st_value);
3261 symbol = strtab + sym.st_name;
3262 stablePtr = (StgStablePtr)lookupHashTable(stablehash, (StgWord)symbol);
3263 if (NULL == stablePtr) {
3264 /* No, so look up the name in our global table. */
3265 S_tmp = lookupSymbol( symbol );
3266 S = (Elf_Addr)S_tmp;
3268 stableVal = deRefStablePtr( stablePtr );
3270 S = (Elf_Addr)S_tmp;
3274 errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
3277 IF_DEBUG(linker,debugBelch( "`%s' resolves to %p\n", symbol, (void*)S ));
3280 IF_DEBUG(linker,debugBelch( "Reloc: P = %p S = %p A = %p\n",
3281 (void*)P, (void*)S, (void*)A ));
3282 checkProddableBlock ( oc, pP );
3286 switch (ELF_R_TYPE(info)) {
3287 # ifdef i386_HOST_ARCH
3288 case R_386_32: *pP = value; break;
3289 case R_386_PC32: *pP = value - P; break;
3292 errorBelch("%s: unhandled ELF relocation(Rel) type %lu\n",
3293 oc->fileName, (lnat)ELF_R_TYPE(info));
3301 /* Do ELF relocations for which explicit addends are supplied.
3302 sparc-solaris relocations appear to be of this form. */
3304 do_Elf_Rela_relocations ( ObjectCode* oc, char* ehdrC,
3305 Elf_Shdr* shdr, int shnum,
3306 Elf_Sym* stab, char* strtab )
3309 char *symbol = NULL;
3311 Elf_Rela* rtab = (Elf_Rela*) (ehdrC + shdr[shnum].sh_offset);
3312 int nent = shdr[shnum].sh_size / sizeof(Elf_Rela);
3313 int target_shndx = shdr[shnum].sh_info;
3314 int symtab_shndx = shdr[shnum].sh_link;
3316 stab = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
3317 targ = (Elf_Addr) (ehdrC + shdr[ target_shndx ].sh_offset);
3318 IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
3319 target_shndx, symtab_shndx ));
3321 for (j = 0; j < nent; j++) {
3322 #if defined(DEBUG) || defined(sparc_HOST_ARCH) || defined(ia64_HOST_ARCH) || defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
3323 /* This #ifdef only serves to avoid unused-var warnings. */
3324 Elf_Addr offset = rtab[j].r_offset;
3325 Elf_Addr P = targ + offset;
3327 Elf_Addr info = rtab[j].r_info;
3328 Elf_Addr A = rtab[j].r_addend;
3332 # if defined(sparc_HOST_ARCH)
3333 Elf_Word* pP = (Elf_Word*)P;
3335 # elif defined(ia64_HOST_ARCH)
3336 Elf64_Xword *pP = (Elf64_Xword *)P;
3338 # elif defined(powerpc_HOST_ARCH)
3342 IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p %6p) ",
3343 j, (void*)offset, (void*)info,
3346 IF_DEBUG(linker,debugBelch( " ZERO" ));
3349 Elf_Sym sym = stab[ELF_R_SYM(info)];
3350 /* First see if it is a local symbol. */
3351 if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
3352 /* Yes, so we can get the address directly from the ELF symbol
3354 symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
3356 (ehdrC + shdr[ sym.st_shndx ].sh_offset
3357 + stab[ELF_R_SYM(info)].st_value);
3358 #ifdef ELF_FUNCTION_DESC
3359 /* Make a function descriptor for this function */
3360 if (S && ELF_ST_TYPE(sym.st_info) == STT_FUNC) {
3361 S = allocateFunctionDesc(S + A);
3366 /* No, so look up the name in our global table. */
3367 symbol = strtab + sym.st_name;
3368 S_tmp = lookupSymbol( symbol );
3369 S = (Elf_Addr)S_tmp;
3371 #ifdef ELF_FUNCTION_DESC
3372 /* If a function, already a function descriptor - we would
3373 have to copy it to add an offset. */
3374 if (S && (ELF_ST_TYPE(sym.st_info) == STT_FUNC) && (A != 0))
3375 errorBelch("%s: function %s with addend %p", oc->fileName, symbol, (void *)A);
3379 errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
3382 IF_DEBUG(linker,debugBelch( "`%s' resolves to %p", symbol, (void*)S ));
3385 IF_DEBUG(linker,debugBelch("Reloc: P = %p S = %p A = %p\n",
3386 (void*)P, (void*)S, (void*)A ));
3387 /* checkProddableBlock ( oc, (void*)P ); */
3391 switch (ELF_R_TYPE(info)) {
3392 # if defined(sparc_HOST_ARCH)
3393 case R_SPARC_WDISP30:
3394 w1 = *pP & 0xC0000000;
3395 w2 = (Elf_Word)((value - P) >> 2);
3396 ASSERT((w2 & 0xC0000000) == 0);
3401 w1 = *pP & 0xFFC00000;
3402 w2 = (Elf_Word)(value >> 10);
3403 ASSERT((w2 & 0xFFC00000) == 0);
3409 w2 = (Elf_Word)(value & 0x3FF);
3410 ASSERT((w2 & ~0x3FF) == 0);
3414 /* According to the Sun documentation:
3416 This relocation type resembles R_SPARC_32, except it refers to an
3417 unaligned word. That is, the word to be relocated must be treated
3418 as four separate bytes with arbitrary alignment, not as a word
3419 aligned according to the architecture requirements.
3421 (JRS: which means that freeloading on the R_SPARC_32 case
3422 is probably wrong, but hey ...)
3426 w2 = (Elf_Word)value;
3429 # elif defined(ia64_HOST_ARCH)
3430 case R_IA64_DIR64LSB:
3431 case R_IA64_FPTR64LSB:
3434 case R_IA64_PCREL64LSB:
3437 case R_IA64_SEGREL64LSB:
3438 addr = findElfSegment(ehdrC, value);
3441 case R_IA64_GPREL22:
3442 ia64_reloc_gprel22(P, value);
3444 case R_IA64_LTOFF22:
3445 case R_IA64_LTOFF22X:
3446 case R_IA64_LTOFF_FPTR22:
3447 addr = allocateGOTEntry(value);
3448 ia64_reloc_gprel22(P, addr);
3450 case R_IA64_PCREL21B:
3451 ia64_reloc_pcrel21(P, S, oc);
3454 /* This goes with R_IA64_LTOFF22X and points to the load to
3455 * convert into a move. We don't implement relaxation. */
3457 # elif defined(powerpc_HOST_ARCH)
3458 case R_PPC_ADDR16_LO:
3459 *(Elf32_Half*) P = value;
3462 case R_PPC_ADDR16_HI:
3463 *(Elf32_Half*) P = value >> 16;
3466 case R_PPC_ADDR16_HA:
3467 *(Elf32_Half*) P = (value + 0x8000) >> 16;
3471 *(Elf32_Word *) P = value;
3475 *(Elf32_Word *) P = value - P;
3481 if( delta << 6 >> 6 != delta )
3483 value = (Elf_Addr) (&makeSymbolExtra( oc, ELF_R_SYM(info), value )
3487 if( value == 0 || delta << 6 >> 6 != delta )
3489 barf( "Unable to make SymbolExtra for #%d",
3495 *(Elf_Word *) P = (*(Elf_Word *) P & 0xfc000003)
3496 | (delta & 0x3fffffc);
3500 #if x86_64_HOST_ARCH
3502 *(Elf64_Xword *)P = value;
3507 StgInt64 off = value - P;
3508 if (off >= 0x7fffffffL || off < -0x80000000L) {
3509 #if X86_64_ELF_NONPIC_HACK
3510 StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3512 off = pltAddress + A - P;
3514 barf("R_X86_64_PC32 relocation out of range: %s = %p\nRecompile %s with -fPIC.",
3515 symbol, off, oc->fileName );
3518 *(Elf64_Word *)P = (Elf64_Word)off;
3524 StgInt64 off = value - P;
3525 *(Elf64_Word *)P = (Elf64_Word)off;
3530 if (value >= 0x7fffffffL) {
3531 #if X86_64_ELF_NONPIC_HACK
3532 StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3534 value = pltAddress + A;
3536 barf("R_X86_64_32 relocation out of range: %s = %p\nRecompile %s with -fPIC.",
3537 symbol, value, oc->fileName );
3540 *(Elf64_Word *)P = (Elf64_Word)value;
3544 if ((StgInt64)value > 0x7fffffffL || (StgInt64)value < -0x80000000L) {
3545 #if X86_64_ELF_NONPIC_HACK
3546 StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3548 value = pltAddress + A;
3550 barf("R_X86_64_32S relocation out of range: %s = %p\nRecompile %s with -fPIC.",
3551 symbol, value, oc->fileName );
3554 *(Elf64_Sword *)P = (Elf64_Sword)value;
3557 case R_X86_64_GOTPCREL:
3559 StgInt64 gotAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)->addr;
3560 StgInt64 off = gotAddress + A - P;
3561 *(Elf64_Word *)P = (Elf64_Word)off;
3565 case R_X86_64_PLT32:
3567 StgInt64 off = value - P;
3568 if (off >= 0x7fffffffL || off < -0x80000000L) {
3569 StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3571 off = pltAddress + A - P;
3573 *(Elf64_Word *)P = (Elf64_Word)off;
3579 errorBelch("%s: unhandled ELF relocation(RelA) type %lu\n",
3580 oc->fileName, (lnat)ELF_R_TYPE(info));
3589 ocResolve_ELF ( ObjectCode* oc )
3593 Elf_Sym* stab = NULL;
3594 char* ehdrC = (char*)(oc->image);
3595 Elf_Ehdr* ehdr = (Elf_Ehdr*) ehdrC;
3596 Elf_Shdr* shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
3598 /* first find "the" symbol table */
3599 stab = (Elf_Sym*) findElfSection ( ehdrC, SHT_SYMTAB );
3601 /* also go find the string table */
3602 strtab = findElfSection ( ehdrC, SHT_STRTAB );
3604 if (stab == NULL || strtab == NULL) {
3605 errorBelch("%s: can't find string or symbol table", oc->fileName);
3609 /* Process the relocation sections. */
3610 for (shnum = 0; shnum < ehdr->e_shnum; shnum++) {
3611 if (shdr[shnum].sh_type == SHT_REL) {
3612 ok = do_Elf_Rel_relocations ( oc, ehdrC, shdr,
3613 shnum, stab, strtab );
3617 if (shdr[shnum].sh_type == SHT_RELA) {
3618 ok = do_Elf_Rela_relocations ( oc, ehdrC, shdr,
3619 shnum, stab, strtab );
3624 /* Free the local symbol table; we won't need it again. */
3625 freeHashTable(oc->lochash, NULL);
3628 #if defined(powerpc_HOST_ARCH)
3629 ocFlushInstructionCache( oc );
3637 * Instructions are 41 bits long, packed into 128 bit bundles with a 5-bit template
3638 * at the front. The following utility functions pack and unpack instructions, and
3639 * take care of the most common relocations.
3642 #ifdef ia64_HOST_ARCH
3645 ia64_extract_instruction(Elf64_Xword *target)
3648 int slot = (Elf_Addr)target & 3;
3649 target = (Elf_Addr)target & ~3;
3657 return ((w1 >> 5) & 0x1ffffffffff);
3659 return (w1 >> 46) | ((w2 & 0x7fffff) << 18);
3663 barf("ia64_extract_instruction: invalid slot %p", target);
3668 ia64_deposit_instruction(Elf64_Xword *target, Elf64_Xword value)
3670 int slot = (Elf_Addr)target & 3;
3671 target = (Elf_Addr)target & ~3;
3676 *target |= value << 5;
3679 *target |= value << 46;
3680 *(target+1) |= value >> 18;
3683 *(target+1) |= value << 23;
3689 ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value)
3691 Elf64_Xword instruction;
3692 Elf64_Sxword rel_value;
3694 rel_value = value - gp_val;
3695 if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff))
3696 barf("GP-relative data out of range (address = 0x%lx, gp = 0x%lx)", value, gp_val);
3698 instruction = ia64_extract_instruction((Elf64_Xword *)target);
3699 instruction |= (((rel_value >> 0) & 0x07f) << 13) /* imm7b */
3700 | (((rel_value >> 7) & 0x1ff) << 27) /* imm9d */
3701 | (((rel_value >> 16) & 0x01f) << 22) /* imm5c */
3702 | ((Elf64_Xword)(rel_value < 0) << 36); /* s */
3703 ia64_deposit_instruction((Elf64_Xword *)target, instruction);
3707 ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc)
3709 Elf64_Xword instruction;
3710 Elf64_Sxword rel_value;
3713 entry = allocatePLTEntry(value, oc);
3715 rel_value = (entry >> 4) - (target >> 4);
3716 if ((rel_value > 0xfffff) || (rel_value < -0xfffff))
3717 barf("PLT entry too far away (entry = 0x%lx, target = 0x%lx)", entry, target);
3719 instruction = ia64_extract_instruction((Elf64_Xword *)target);
3720 instruction |= ((rel_value & 0xfffff) << 13) /* imm20b */
3721 | ((Elf64_Xword)(rel_value < 0) << 36); /* s */
3722 ia64_deposit_instruction((Elf64_Xword *)target, instruction);
3728 * PowerPC & X86_64 ELF specifics
3731 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
3733 static int ocAllocateSymbolExtras_ELF( ObjectCode *oc )
3739 ehdr = (Elf_Ehdr *) oc->image;
3740 shdr = (Elf_Shdr *) ( ((char *)oc->image) + ehdr->e_shoff );
3742 for( i = 0; i < ehdr->e_shnum; i++ )
3743 if( shdr[i].sh_type == SHT_SYMTAB )
3746 if( i == ehdr->e_shnum )
3748 errorBelch( "This ELF file contains no symtab" );
3752 if( shdr[i].sh_entsize != sizeof( Elf_Sym ) )
3754 errorBelch( "The entry size (%d) of the symtab isn't %d\n",
3755 (int) shdr[i].sh_entsize, (int) sizeof( Elf_Sym ) );
3760 return ocAllocateSymbolExtras( oc, shdr[i].sh_size / sizeof( Elf_Sym ), 0 );
3763 #endif /* powerpc */
3767 /* --------------------------------------------------------------------------
3769 * ------------------------------------------------------------------------*/
3771 #if defined(OBJFORMAT_MACHO)
3774 Support for MachO linking on Darwin/MacOS X
3775 by Wolfgang Thaller (wolfgang.thaller@gmx.net)
3777 I hereby formally apologize for the hackish nature of this code.
3778 Things that need to be done:
3779 *) implement ocVerifyImage_MachO
3780 *) add still more sanity checks.
3783 #if x86_64_HOST_ARCH || powerpc64_HOST_ARCH
3784 #define mach_header mach_header_64
3785 #define segment_command segment_command_64
3786 #define section section_64
3787 #define nlist nlist_64
3790 #ifdef powerpc_HOST_ARCH
3791 static int ocAllocateSymbolExtras_MachO(ObjectCode* oc)
3793 struct mach_header *header = (struct mach_header *) oc->image;
3794 struct load_command *lc = (struct load_command *) (header + 1);
3797 for( i = 0; i < header->ncmds; i++ )
3799 if( lc->cmd == LC_SYMTAB )
3801 // Find out the first and last undefined external
3802 // symbol, so we don't have to allocate too many
3804 struct symtab_command *symLC = (struct symtab_command *) lc;
3805 unsigned min = symLC->nsyms, max = 0;
3806 struct nlist *nlist =
3807 symLC ? (struct nlist*) ((char*) oc->image + symLC->symoff)
3809 for(i=0;i<symLC->nsyms;i++)
3811 if(nlist[i].n_type & N_STAB)
3813 else if(nlist[i].n_type & N_EXT)
3815 if((nlist[i].n_type & N_TYPE) == N_UNDF
3816 && (nlist[i].n_value == 0))
3826 return ocAllocateSymbolExtras(oc, max - min + 1, min);
3831 lc = (struct load_command *) ( ((char *)lc) + lc->cmdsize );
3833 return ocAllocateSymbolExtras(oc,0,0);
3836 #ifdef x86_64_HOST_ARCH
3837 static int ocAllocateSymbolExtras_MachO(ObjectCode* oc)
3839 struct mach_header *header = (struct mach_header *) oc->image;
3840 struct load_command *lc = (struct load_command *) (header + 1);
3843 for( i = 0; i < header->ncmds; i++ )
3845 if( lc->cmd == LC_SYMTAB )
3847 // Just allocate one entry for every symbol
3848 struct symtab_command *symLC = (struct symtab_command *) lc;
3850 return ocAllocateSymbolExtras(oc, symLC->nsyms, 0);
3853 lc = (struct load_command *) ( ((char *)lc) + lc->cmdsize );
3855 return ocAllocateSymbolExtras(oc,0,0);
3859 static int ocVerifyImage_MachO(ObjectCode* oc)
3861 char *image = (char*) oc->image;
3862 struct mach_header *header = (struct mach_header*) image;
3864 #if x86_64_TARGET_ARCH || powerpc64_TARGET_ARCH
3865 if(header->magic != MH_MAGIC_64)
3868 if(header->magic != MH_MAGIC)
3871 // FIXME: do some more verifying here
3875 static int resolveImports(
3878 struct symtab_command *symLC,
3879 struct section *sect, // ptr to lazy or non-lazy symbol pointer section
3880 unsigned long *indirectSyms,
3881 struct nlist *nlist)
3884 size_t itemSize = 4;
3887 int isJumpTable = 0;
3888 if(!strcmp(sect->sectname,"__jump_table"))
3892 ASSERT(sect->reserved2 == itemSize);
3896 for(i=0; i*itemSize < sect->size;i++)
3898 // according to otool, reserved1 contains the first index into the indirect symbol table
3899 struct nlist *symbol = &nlist[indirectSyms[sect->reserved1+i]];
3900 char *nm = image + symLC->stroff + symbol->n_un.n_strx;
3903 if((symbol->n_type & N_TYPE) == N_UNDF
3904 && (symbol->n_type & N_EXT) && (symbol->n_value != 0))
3905 addr = (void*) (symbol->n_value);
3906 else if((addr = lookupLocalSymbol(oc,nm)) != NULL)
3909 addr = lookupSymbol(nm);
3912 errorBelch("\n%s: unknown symbol `%s'", oc->fileName, nm);
3920 checkProddableBlock(oc,image + sect->offset + i*itemSize);
3921 *(image + sect->offset + i*itemSize) = 0xe9; // jmp
3922 *(unsigned*)(image + sect->offset + i*itemSize + 1)
3923 = (char*)addr - (image + sect->offset + i*itemSize + 5);
3928 checkProddableBlock(oc,((void**)(image + sect->offset)) + i);
3929 ((void**)(image + sect->offset))[i] = addr;
3936 static unsigned long relocateAddress(
3939 struct section* sections,
3940 unsigned long address)
3943 for(i = 0; i < nSections; i++)
3945 if(sections[i].addr <= address
3946 && address < sections[i].addr + sections[i].size)
3948 return (unsigned long)oc->image
3949 + sections[i].offset + address - sections[i].addr;
3952 barf("Invalid Mach-O file:"
3953 "Address out of bounds while relocating object file");
3957 static int relocateSection(
3960 struct symtab_command *symLC, struct nlist *nlist,
3961 int nSections, struct section* sections, struct section *sect)
3963 struct relocation_info *relocs;
3966 if(!strcmp(sect->sectname,"__la_symbol_ptr"))
3968 else if(!strcmp(sect->sectname,"__nl_symbol_ptr"))
3970 else if(!strcmp(sect->sectname,"__la_sym_ptr2"))
3972 else if(!strcmp(sect->sectname,"__la_sym_ptr3"))
3976 relocs = (struct relocation_info*) (image + sect->reloff);
3980 #ifdef x86_64_HOST_ARCH
3981 struct relocation_info *reloc = &relocs[i];
3983 char *thingPtr = image + sect->offset + reloc->r_address;
3987 int type = reloc->r_type;
3989 checkProddableBlock(oc,thingPtr);
3990 switch(reloc->r_length)
3993 thing = *(uint8_t*)thingPtr;
3994 baseValue = (uint64_t)thingPtr + 1;
3997 thing = *(uint16_t*)thingPtr;
3998 baseValue = (uint64_t)thingPtr + 2;
4001 thing = *(uint32_t*)thingPtr;
4002 baseValue = (uint64_t)thingPtr + 4;
4005 thing = *(uint64_t*)thingPtr;
4006 baseValue = (uint64_t)thingPtr + 8;
4009 barf("Unknown size.");
4012 if(type == X86_64_RELOC_GOT
4013 || type == X86_64_RELOC_GOT_LOAD)
4015 ASSERT(reloc->r_extern);
4016 value = (uint64_t) &makeSymbolExtra(oc, reloc->r_symbolnum, value)->addr;
4018 type = X86_64_RELOC_SIGNED;
4020 else if(reloc->r_extern)
4022 struct nlist *symbol = &nlist[reloc->r_symbolnum];
4023 char *nm = image + symLC->stroff + symbol->n_un.n_strx;
4024 if(symbol->n_value == 0)
4025 value = (uint64_t) lookupSymbol(nm);
4027 value = relocateAddress(oc, nSections, sections,
4032 value = sections[reloc->r_symbolnum-1].offset
4033 - sections[reloc->r_symbolnum-1].addr
4037 if(type == X86_64_RELOC_BRANCH)
4039 if((int32_t)(value - baseValue) != (int64_t)(value - baseValue))
4041 ASSERT(reloc->r_extern);
4042 value = (uint64_t) &makeSymbolExtra(oc, reloc->r_symbolnum, value)
4045 ASSERT((int32_t)(value - baseValue) == (int64_t)(value - baseValue));
4046 type = X86_64_RELOC_SIGNED;
4051 case X86_64_RELOC_UNSIGNED:
4052 ASSERT(!reloc->r_pcrel);
4055 case X86_64_RELOC_SIGNED:
4056 ASSERT(reloc->r_pcrel);
4057 thing += value - baseValue;
4059 case X86_64_RELOC_SUBTRACTOR:
4060 ASSERT(!reloc->r_pcrel);
4064 barf("unkown relocation");
4067 switch(reloc->r_length)
4070 *(uint8_t*)thingPtr = thing;
4073 *(uint16_t*)thingPtr = thing;
4076 *(uint32_t*)thingPtr = thing;
4079 *(uint64_t*)thingPtr = thing;
4083 if(relocs[i].r_address & R_SCATTERED)
4085 struct scattered_relocation_info *scat =
4086 (struct scattered_relocation_info*) &relocs[i];
4090 if(scat->r_length == 2)
4092 unsigned long word = 0;
4093 unsigned long* wordPtr = (unsigned long*) (image + sect->offset + scat->r_address);
4094 checkProddableBlock(oc,wordPtr);
4096 // Note on relocation types:
4097 // i386 uses the GENERIC_RELOC_* types,
4098 // while ppc uses special PPC_RELOC_* types.
4099 // *_RELOC_VANILLA and *_RELOC_PAIR have the same value
4100 // in both cases, all others are different.
4101 // Therefore, we use GENERIC_RELOC_VANILLA
4102 // and GENERIC_RELOC_PAIR instead of the PPC variants,
4103 // and use #ifdefs for the other types.
4105 // Step 1: Figure out what the relocated value should be
4106 if(scat->r_type == GENERIC_RELOC_VANILLA)
4108 word = *wordPtr + (unsigned long) relocateAddress(
4115 #ifdef powerpc_HOST_ARCH
4116 else if(scat->r_type == PPC_RELOC_SECTDIFF
4117 || scat->r_type == PPC_RELOC_LO16_SECTDIFF
4118 || scat->r_type == PPC_RELOC_HI16_SECTDIFF
4119 || scat->r_type == PPC_RELOC_HA16_SECTDIFF)
4121 else if(scat->r_type == GENERIC_RELOC_SECTDIFF)
4124 struct scattered_relocation_info *pair =
4125 (struct scattered_relocation_info*) &relocs[i+1];
4127 if(!pair->r_scattered || pair->r_type != GENERIC_RELOC_PAIR)
4128 barf("Invalid Mach-O file: "
4129 "RELOC_*_SECTDIFF not followed by RELOC_PAIR");
4131 word = (unsigned long)
4132 (relocateAddress(oc, nSections, sections, scat->r_value)
4133 - relocateAddress(oc, nSections, sections, pair->r_value));
4136 #ifdef powerpc_HOST_ARCH
4137 else if(scat->r_type == PPC_RELOC_HI16
4138 || scat->r_type == PPC_RELOC_LO16
4139 || scat->r_type == PPC_RELOC_HA16
4140 || scat->r_type == PPC_RELOC_LO14)
4141 { // these are generated by label+offset things
4142 struct relocation_info *pair = &relocs[i+1];
4143 if((pair->r_address & R_SCATTERED) || pair->r_type != PPC_RELOC_PAIR)
4144 barf("Invalid Mach-O file: "
4145 "PPC_RELOC_* not followed by PPC_RELOC_PAIR");
4147 if(scat->r_type == PPC_RELOC_LO16)
4149 word = ((unsigned short*) wordPtr)[1];
4150 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4152 else if(scat->r_type == PPC_RELOC_LO14)
4154 barf("Unsupported Relocation: PPC_RELOC_LO14");
4155 word = ((unsigned short*) wordPtr)[1] & 0xFFFC;
4156 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4158 else if(scat->r_type == PPC_RELOC_HI16)
4160 word = ((unsigned short*) wordPtr)[1] << 16;
4161 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
4163 else if(scat->r_type == PPC_RELOC_HA16)
4165 word = ((unsigned short*) wordPtr)[1] << 16;
4166 word += ((short)relocs[i+1].r_address & (short)0xFFFF);
4170 word += (unsigned long) relocateAddress(oc, nSections, sections, scat->r_value)
4177 continue; // ignore the others
4179 #ifdef powerpc_HOST_ARCH
4180 if(scat->r_type == GENERIC_RELOC_VANILLA
4181 || scat->r_type == PPC_RELOC_SECTDIFF)
4183 if(scat->r_type == GENERIC_RELOC_VANILLA
4184 || scat->r_type == GENERIC_RELOC_SECTDIFF)
4189 #ifdef powerpc_HOST_ARCH
4190 else if(scat->r_type == PPC_RELOC_LO16_SECTDIFF || scat->r_type == PPC_RELOC_LO16)
4192 ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
4194 else if(scat->r_type == PPC_RELOC_HI16_SECTDIFF || scat->r_type == PPC_RELOC_HI16)
4196 ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
4198 else if(scat->r_type == PPC_RELOC_HA16_SECTDIFF || scat->r_type == PPC_RELOC_HA16)
4200 ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
4201 + ((word & (1<<15)) ? 1 : 0);
4207 continue; // FIXME: I hope it's OK to ignore all the others.
4211 struct relocation_info *reloc = &relocs[i];
4212 if(reloc->r_pcrel && !reloc->r_extern)
4215 if(reloc->r_length == 2)
4217 unsigned long word = 0;
4218 #ifdef powerpc_HOST_ARCH
4219 unsigned long jumpIsland = 0;
4220 long offsetToJumpIsland = 0xBADBAD42; // initialise to bad value
4221 // to avoid warning and to catch
4225 unsigned long* wordPtr = (unsigned long*) (image + sect->offset + reloc->r_address);
4226 checkProddableBlock(oc,wordPtr);
4228 if(reloc->r_type == GENERIC_RELOC_VANILLA)
4232 #ifdef powerpc_HOST_ARCH
4233 else if(reloc->r_type == PPC_RELOC_LO16)
4235 word = ((unsigned short*) wordPtr)[1];
4236 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4238 else if(reloc->r_type == PPC_RELOC_HI16)
4240 word = ((unsigned short*) wordPtr)[1] << 16;
4241 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
4243 else if(reloc->r_type == PPC_RELOC_HA16)
4245 word = ((unsigned short*) wordPtr)[1] << 16;
4246 word += ((short)relocs[i+1].r_address & (short)0xFFFF);
4248 else if(reloc->r_type == PPC_RELOC_BR24)
4251 word = (word & 0x03FFFFFC) | ((word & 0x02000000) ? 0xFC000000 : 0);
4255 if(!reloc->r_extern)
4258 sections[reloc->r_symbolnum-1].offset
4259 - sections[reloc->r_symbolnum-1].addr
4266 struct nlist *symbol = &nlist[reloc->r_symbolnum];
4267 char *nm = image + symLC->stroff + symbol->n_un.n_strx;
4268 void *symbolAddress = lookupSymbol(nm);
4271 errorBelch("\nunknown symbol `%s'", nm);
4277 #ifdef powerpc_HOST_ARCH
4278 // In the .o file, this should be a relative jump to NULL
4279 // and we'll change it to a relative jump to the symbol
4280 ASSERT(word + reloc->r_address == 0);
4281 jumpIsland = (unsigned long)
4282 &makeSymbolExtra(oc,
4284 (unsigned long) symbolAddress)
4288 offsetToJumpIsland = word + jumpIsland
4289 - (((long)image) + sect->offset - sect->addr);
4292 word += (unsigned long) symbolAddress
4293 - (((long)image) + sect->offset - sect->addr);
4297 word += (unsigned long) symbolAddress;
4301 if(reloc->r_type == GENERIC_RELOC_VANILLA)
4306 #ifdef powerpc_HOST_ARCH
4307 else if(reloc->r_type == PPC_RELOC_LO16)
4309 ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
4312 else if(reloc->r_type == PPC_RELOC_HI16)
4314 ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
4317 else if(reloc->r_type == PPC_RELOC_HA16)
4319 ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
4320 + ((word & (1<<15)) ? 1 : 0);
4323 else if(reloc->r_type == PPC_RELOC_BR24)
4325 if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
4327 // The branch offset is too large.
4328 // Therefore, we try to use a jump island.
4331 barf("unconditional relative branch out of range: "
4332 "no jump island available");
4335 word = offsetToJumpIsland;
4336 if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
4337 barf("unconditional relative branch out of range: "
4338 "jump island out of range");
4340 *wordPtr = (*wordPtr & 0xFC000003) | (word & 0x03FFFFFC);
4345 barf("\nunknown relocation %d",reloc->r_type);
4353 static int ocGetNames_MachO(ObjectCode* oc)
4355 char *image = (char*) oc->image;
4356 struct mach_header *header = (struct mach_header*) image;
4357 struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
4358 unsigned i,curSymbol = 0;
4359 struct segment_command *segLC = NULL;
4360 struct section *sections;
4361 struct symtab_command *symLC = NULL;
4362 struct nlist *nlist;
4363 unsigned long commonSize = 0;
4364 char *commonStorage = NULL;
4365 unsigned long commonCounter;
4367 for(i=0;i<header->ncmds;i++)
4369 if(lc->cmd == LC_SEGMENT || lc->cmd == LC_SEGMENT_64)
4370 segLC = (struct segment_command*) lc;
4371 else if(lc->cmd == LC_SYMTAB)
4372 symLC = (struct symtab_command*) lc;
4373 lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
4376 sections = (struct section*) (segLC+1);
4377 nlist = symLC ? (struct nlist*) (image + symLC->symoff)
4381 barf("ocGetNames_MachO: no segment load command");
4383 for(i=0;i<segLC->nsects;i++)
4385 if(sections[i].size == 0)
4388 if((sections[i].flags & SECTION_TYPE) == S_ZEROFILL)
4390 char * zeroFillArea = stgCallocBytes(1,sections[i].size,
4391 "ocGetNames_MachO(common symbols)");
4392 sections[i].offset = zeroFillArea - image;
4395 if(!strcmp(sections[i].sectname,"__text"))
4396 addSection(oc, SECTIONKIND_CODE_OR_RODATA,
4397 (void*) (image + sections[i].offset),
4398 (void*) (image + sections[i].offset + sections[i].size));
4399 else if(!strcmp(sections[i].sectname,"__const"))
4400 addSection(oc, SECTIONKIND_RWDATA,
4401 (void*) (image + sections[i].offset),
4402 (void*) (image + sections[i].offset + sections[i].size));
4403 else if(!strcmp(sections[i].sectname,"__data"))
4404 addSection(oc, SECTIONKIND_RWDATA,
4405 (void*) (image + sections[i].offset),
4406 (void*) (image + sections[i].offset + sections[i].size));
4407 else if(!strcmp(sections[i].sectname,"__bss")
4408 || !strcmp(sections[i].sectname,"__common"))
4409 addSection(oc, SECTIONKIND_RWDATA,
4410 (void*) (image + sections[i].offset),
4411 (void*) (image + sections[i].offset + sections[i].size));
4413 addProddableBlock(oc, (void*) (image + sections[i].offset),
4417 // count external symbols defined here
4421 for(i=0;i<symLC->nsyms;i++)
4423 if(nlist[i].n_type & N_STAB)
4425 else if(nlist[i].n_type & N_EXT)
4427 if((nlist[i].n_type & N_TYPE) == N_UNDF
4428 && (nlist[i].n_value != 0))
4430 commonSize += nlist[i].n_value;
4433 else if((nlist[i].n_type & N_TYPE) == N_SECT)
4438 oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
4439 "ocGetNames_MachO(oc->symbols)");
4443 for(i=0;i<symLC->nsyms;i++)
4445 if(nlist[i].n_type & N_STAB)
4447 else if((nlist[i].n_type & N_TYPE) == N_SECT)
4449 if(nlist[i].n_type & N_EXT)
4451 char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
4452 if((nlist[i].n_desc & N_WEAK_DEF) && lookupSymbol(nm))
4453 ; // weak definition, and we already have a definition
4456 ghciInsertStrHashTable(oc->fileName, symhash, nm,
4458 + sections[nlist[i].n_sect-1].offset
4459 - sections[nlist[i].n_sect-1].addr
4460 + nlist[i].n_value);
4461 oc->symbols[curSymbol++] = nm;
4468 commonStorage = stgCallocBytes(1,commonSize,"ocGetNames_MachO(common symbols)");
4469 commonCounter = (unsigned long)commonStorage;
4472 for(i=0;i<symLC->nsyms;i++)
4474 if((nlist[i].n_type & N_TYPE) == N_UNDF
4475 && (nlist[i].n_type & N_EXT) && (nlist[i].n_value != 0))
4477 char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
4478 unsigned long sz = nlist[i].n_value;
4480 nlist[i].n_value = commonCounter;
4482 ghciInsertStrHashTable(oc->fileName, symhash, nm,
4483 (void*)commonCounter);
4484 oc->symbols[curSymbol++] = nm;
4486 commonCounter += sz;
4493 static int ocResolve_MachO(ObjectCode* oc)
4495 char *image = (char*) oc->image;
4496 struct mach_header *header = (struct mach_header*) image;
4497 struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
4499 struct segment_command *segLC = NULL;
4500 struct section *sections;
4501 struct symtab_command *symLC = NULL;
4502 struct dysymtab_command *dsymLC = NULL;
4503 struct nlist *nlist;
4505 for(i=0;i<header->ncmds;i++)
4507 if(lc->cmd == LC_SEGMENT || lc->cmd == LC_SEGMENT_64)
4508 segLC = (struct segment_command*) lc;
4509 else if(lc->cmd == LC_SYMTAB)
4510 symLC = (struct symtab_command*) lc;
4511 else if(lc->cmd == LC_DYSYMTAB)
4512 dsymLC = (struct dysymtab_command*) lc;
4513 lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
4516 sections = (struct section*) (segLC+1);
4517 nlist = symLC ? (struct nlist*) (image + symLC->symoff)
4522 unsigned long *indirectSyms
4523 = (unsigned long*) (image + dsymLC->indirectsymoff);
4525 for(i=0;i<segLC->nsects;i++)
4527 if( !strcmp(sections[i].sectname,"__la_symbol_ptr")
4528 || !strcmp(sections[i].sectname,"__la_sym_ptr2")
4529 || !strcmp(sections[i].sectname,"__la_sym_ptr3"))
4531 if(!resolveImports(oc,image,symLC,§ions[i],indirectSyms,nlist))
4534 else if(!strcmp(sections[i].sectname,"__nl_symbol_ptr")
4535 || !strcmp(sections[i].sectname,"__pointers"))
4537 if(!resolveImports(oc,image,symLC,§ions[i],indirectSyms,nlist))
4540 else if(!strcmp(sections[i].sectname,"__jump_table"))
4542 if(!resolveImports(oc,image,symLC,§ions[i],indirectSyms,nlist))
4548 for(i=0;i<segLC->nsects;i++)
4550 if(!relocateSection(oc,image,symLC,nlist,segLC->nsects,sections,§ions[i]))
4554 /* Free the local symbol table; we won't need it again. */
4555 freeHashTable(oc->lochash, NULL);
4558 #if defined (powerpc_HOST_ARCH)
4559 ocFlushInstructionCache( oc );
4565 #ifdef powerpc_HOST_ARCH
4567 * The Mach-O object format uses leading underscores. But not everywhere.
4568 * There is a small number of runtime support functions defined in
4569 * libcc_dynamic.a whose name does not have a leading underscore.
4570 * As a consequence, we can't get their address from C code.
4571 * We have to use inline assembler just to take the address of a function.
4575 static void machoInitSymbolsWithoutUnderscore()
4577 extern void* symbolsWithoutUnderscore[];
4578 void **p = symbolsWithoutUnderscore;
4579 __asm__ volatile(".globl _symbolsWithoutUnderscore\n.data\n_symbolsWithoutUnderscore:");
4583 __asm__ volatile(".long " # x);
4585 RTS_MACHO_NOUNDERLINE_SYMBOLS
4587 __asm__ volatile(".text");
4591 ghciInsertStrHashTable("(GHCi built-in symbols)", symhash, #x, *p++);
4593 RTS_MACHO_NOUNDERLINE_SYMBOLS
4600 * Figure out by how much to shift the entire Mach-O file in memory
4601 * when loading so that its single segment ends up 16-byte-aligned
4603 static int machoGetMisalignment( FILE * f )
4605 struct mach_header header;
4608 fread(&header, sizeof(header), 1, f);
4611 #if x86_64_TARGET_ARCH || powerpc64_TARGET_ARCH
4612 if(header.magic != MH_MAGIC_64)
4615 if(header.magic != MH_MAGIC)
4619 misalignment = (header.sizeofcmds + sizeof(header))
4622 return misalignment ? (16 - misalignment) : 0;