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(__word_encodeDouble) \
541 SymX(__2Int_encodeDouble) \
542 SymX(__int_encodeFloat) \
543 SymX(__word_encodeFloat) \
544 SymX(andIntegerzh_fast) \
545 SymX(atomicallyzh_fast) \
549 SymX(blockAsyncExceptionszh_fast) \
551 SymX(catchRetryzh_fast) \
552 SymX(catchSTMzh_fast) \
554 SymX(closure_flags) \
556 SymX(cmpIntegerzh_fast) \
557 SymX(cmpIntegerIntzh_fast) \
558 SymX(complementIntegerzh_fast) \
559 SymX(createAdjustor) \
560 SymX(decodeDoublezh_fast) \
561 SymX(decodeFloatzh_fast) \
562 SymX(decodeDoublezu2Intzh_fast) \
563 SymX(decodeFloatzuIntzh_fast) \
566 SymX(deRefWeakzh_fast) \
567 SymX(deRefStablePtrzh_fast) \
568 SymX(dirty_MUT_VAR) \
569 SymX(divExactIntegerzh_fast) \
570 SymX(divModIntegerzh_fast) \
572 SymX(forkOnzh_fast) \
574 SymX(forkOS_createThread) \
575 SymX(freeHaskellFunctionPtr) \
576 SymX(freeStablePtr) \
577 SymX(getOrSetTypeableStore) \
578 SymX(gcdIntegerzh_fast) \
579 SymX(gcdIntegerIntzh_fast) \
580 SymX(gcdIntzh_fast) \
584 SymX(getFullProgArgv) \
590 SymX(hs_perform_gc) \
591 SymX(hs_free_stable_ptr) \
592 SymX(hs_free_fun_ptr) \
593 SymX(hs_hpc_rootModule) \
595 SymX(unpackClosurezh_fast) \
596 SymX(getApStackValzh_fast) \
597 SymX(int2Integerzh_fast) \
598 SymX(integer2Intzh_fast) \
599 SymX(integer2Wordzh_fast) \
600 SymX(isCurrentThreadBoundzh_fast) \
601 SymX(isDoubleDenormalized) \
602 SymX(isDoubleInfinite) \
604 SymX(isDoubleNegativeZero) \
605 SymX(isEmptyMVarzh_fast) \
606 SymX(isFloatDenormalized) \
607 SymX(isFloatInfinite) \
609 SymX(isFloatNegativeZero) \
610 SymX(killThreadzh_fast) \
612 SymX(insertStableSymbol) \
615 SymX(makeStablePtrzh_fast) \
616 SymX(minusIntegerzh_fast) \
617 SymX(mkApUpd0zh_fast) \
618 SymX(myThreadIdzh_fast) \
619 SymX(labelThreadzh_fast) \
620 SymX(newArrayzh_fast) \
621 SymX(newBCOzh_fast) \
622 SymX(newByteArrayzh_fast) \
623 SymX_redirect(newCAF, newDynCAF) \
624 SymX(newMVarzh_fast) \
625 SymX(newMutVarzh_fast) \
626 SymX(newTVarzh_fast) \
627 SymX(noDuplicatezh_fast) \
628 SymX(atomicModifyMutVarzh_fast) \
629 SymX(newPinnedByteArrayzh_fast) \
631 SymX(orIntegerzh_fast) \
633 SymX(performMajorGC) \
634 SymX(plusIntegerzh_fast) \
637 SymX(putMVarzh_fast) \
638 SymX(quotIntegerzh_fast) \
639 SymX(quotRemIntegerzh_fast) \
641 SymX(raiseIOzh_fast) \
642 SymX(readTVarzh_fast) \
643 SymX(remIntegerzh_fast) \
644 SymX(resetNonBlockingFd) \
649 SymX(rts_checkSchedStatus) \
652 SymX(rts_evalLazyIO) \
653 SymX(rts_evalStableIO) \
657 SymX(rts_getDouble) \
665 SymX(rts_getFunPtr) \
666 SymX(rts_getStablePtr) \
667 SymX(rts_getThreadId) \
670 SymX(rts_getWord16) \
671 SymX(rts_getWord32) \
672 SymX(rts_getWord64) \
685 SymX(rts_mkStablePtr) \
693 SymX(rtsSupportsBoundThreads) \
694 SymX(__hscore_get_saved_termios) \
695 SymX(__hscore_set_saved_termios) \
697 SymX(startupHaskell) \
698 SymX(shutdownHaskell) \
699 SymX(shutdownHaskellAndExit) \
700 SymX(stable_ptr_table) \
701 SymX(stackOverflow) \
702 SymX(stg_CAF_BLACKHOLE_info) \
703 SymX(awakenBlockedQueue) \
704 SymX(stg_CHARLIKE_closure) \
705 SymX(stg_MVAR_CLEAN_info) \
706 SymX(stg_MVAR_DIRTY_info) \
707 SymX(stg_IND_STATIC_info) \
708 SymX(stg_INTLIKE_closure) \
709 SymX(stg_MUT_ARR_PTRS_DIRTY_info) \
710 SymX(stg_MUT_ARR_PTRS_FROZEN_info) \
711 SymX(stg_MUT_ARR_PTRS_FROZEN0_info) \
712 SymX(stg_WEAK_info) \
713 SymX(stg_ap_v_info) \
714 SymX(stg_ap_f_info) \
715 SymX(stg_ap_d_info) \
716 SymX(stg_ap_l_info) \
717 SymX(stg_ap_n_info) \
718 SymX(stg_ap_p_info) \
719 SymX(stg_ap_pv_info) \
720 SymX(stg_ap_pp_info) \
721 SymX(stg_ap_ppv_info) \
722 SymX(stg_ap_ppp_info) \
723 SymX(stg_ap_pppv_info) \
724 SymX(stg_ap_pppp_info) \
725 SymX(stg_ap_ppppp_info) \
726 SymX(stg_ap_pppppp_info) \
727 SymX(stg_ap_0_fast) \
728 SymX(stg_ap_v_fast) \
729 SymX(stg_ap_f_fast) \
730 SymX(stg_ap_d_fast) \
731 SymX(stg_ap_l_fast) \
732 SymX(stg_ap_n_fast) \
733 SymX(stg_ap_p_fast) \
734 SymX(stg_ap_pv_fast) \
735 SymX(stg_ap_pp_fast) \
736 SymX(stg_ap_ppv_fast) \
737 SymX(stg_ap_ppp_fast) \
738 SymX(stg_ap_pppv_fast) \
739 SymX(stg_ap_pppp_fast) \
740 SymX(stg_ap_ppppp_fast) \
741 SymX(stg_ap_pppppp_fast) \
742 SymX(stg_ap_1_upd_info) \
743 SymX(stg_ap_2_upd_info) \
744 SymX(stg_ap_3_upd_info) \
745 SymX(stg_ap_4_upd_info) \
746 SymX(stg_ap_5_upd_info) \
747 SymX(stg_ap_6_upd_info) \
748 SymX(stg_ap_7_upd_info) \
750 SymX(stg_sel_0_upd_info) \
751 SymX(stg_sel_10_upd_info) \
752 SymX(stg_sel_11_upd_info) \
753 SymX(stg_sel_12_upd_info) \
754 SymX(stg_sel_13_upd_info) \
755 SymX(stg_sel_14_upd_info) \
756 SymX(stg_sel_15_upd_info) \
757 SymX(stg_sel_1_upd_info) \
758 SymX(stg_sel_2_upd_info) \
759 SymX(stg_sel_3_upd_info) \
760 SymX(stg_sel_4_upd_info) \
761 SymX(stg_sel_5_upd_info) \
762 SymX(stg_sel_6_upd_info) \
763 SymX(stg_sel_7_upd_info) \
764 SymX(stg_sel_8_upd_info) \
765 SymX(stg_sel_9_upd_info) \
766 SymX(stg_upd_frame_info) \
767 SymX(suspendThread) \
768 SymX(takeMVarzh_fast) \
769 SymX(timesIntegerzh_fast) \
770 SymX(tryPutMVarzh_fast) \
771 SymX(tryTakeMVarzh_fast) \
772 SymX(unblockAsyncExceptionszh_fast) \
774 SymX(unsafeThawArrayzh_fast) \
775 SymX(waitReadzh_fast) \
776 SymX(waitWritezh_fast) \
777 SymX(word2Integerzh_fast) \
778 SymX(writeTVarzh_fast) \
779 SymX(xorIntegerzh_fast) \
781 Sym(stg_interp_constr_entry) \
784 SymX(getAllocations) \
787 Sym(rts_breakpoint_io_action) \
788 Sym(rts_stop_next_breakpoint) \
789 Sym(rts_stop_on_exception) \
791 SymX(n_capabilities) \
792 RTS_USER_SIGNALS_SYMBOLS
794 #ifdef SUPPORT_LONG_LONGS
795 #define RTS_LONG_LONG_SYMS \
796 SymX(int64ToIntegerzh_fast) \
797 SymX(word64ToIntegerzh_fast)
799 #define RTS_LONG_LONG_SYMS /* nothing */
802 // 64-bit support functions in libgcc.a
803 #if defined(__GNUC__) && SIZEOF_VOID_P <= 4
804 #define RTS_LIBGCC_SYMBOLS \
814 #elif defined(ia64_HOST_ARCH)
815 #define RTS_LIBGCC_SYMBOLS \
823 #define RTS_LIBGCC_SYMBOLS
826 #if defined(darwin_HOST_OS) && defined(powerpc_HOST_ARCH)
827 // Symbols that don't have a leading underscore
828 // on Mac OS X. They have to receive special treatment,
829 // see machoInitSymbolsWithoutUnderscore()
830 #define RTS_MACHO_NOUNDERLINE_SYMBOLS \
835 /* entirely bogus claims about types of these symbols */
836 #define Sym(vvv) extern void vvv(void);
837 #if defined(__PIC__) && defined(mingw32_TARGET_OS)
838 #define SymExtern(vvv) extern void _imp__ ## vvv (void);
840 #define SymExtern(vvv) SymX(vvv)
842 #define SymX(vvv) /**/
843 #define SymX_redirect(vvv,xxx) /**/
847 RTS_POSIX_ONLY_SYMBOLS
848 RTS_MINGW_ONLY_SYMBOLS
849 RTS_CYGWIN_ONLY_SYMBOLS
850 RTS_DARWIN_ONLY_SYMBOLS
858 #ifdef LEADING_UNDERSCORE
859 #define MAYBE_LEADING_UNDERSCORE_STR(s) ("_" s)
861 #define MAYBE_LEADING_UNDERSCORE_STR(s) (s)
864 #define Sym(vvv) { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
866 #define SymX(vvv) Sym(vvv)
867 #define SymExtern(vvv) { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
868 (void*)DLL_IMPORT_DATA_REF(vvv) },
870 // SymX_redirect allows us to redirect references to one symbol to
871 // another symbol. See newCAF/newDynCAF for an example.
872 #define SymX_redirect(vvv,xxx) \
873 { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
876 static RtsSymbolVal rtsSyms[] = {
880 RTS_POSIX_ONLY_SYMBOLS
881 RTS_MINGW_ONLY_SYMBOLS
882 RTS_CYGWIN_ONLY_SYMBOLS
883 RTS_DARWIN_ONLY_SYMBOLS
886 #if defined(darwin_HOST_OS) && defined(i386_HOST_ARCH)
887 // dyld stub code contains references to this,
888 // but it should never be called because we treat
889 // lazy pointers as nonlazy.
890 { "dyld_stub_binding_helper", (void*)0xDEADBEEF },
892 { 0, 0 } /* sentinel */
897 /* -----------------------------------------------------------------------------
898 * Insert symbols into hash tables, checking for duplicates.
901 static void ghciInsertStrHashTable ( char* obj_name,
907 if (lookupHashTable(table, (StgWord)key) == NULL)
909 insertStrHashTable(table, (StgWord)key, data);
914 "GHCi runtime linker: fatal error: I found a duplicate definition for symbol\n"
916 "whilst processing object file\n"
918 "This could be caused by:\n"
919 " * Loading two different object files which export the same symbol\n"
920 " * Specifying the same object file twice on the GHCi command line\n"
921 " * An incorrect `package.conf' entry, causing some object to be\n"
923 "GHCi cannot safely continue in this situation. Exiting now. Sorry.\n"
930 /* -----------------------------------------------------------------------------
931 * initialize the object linker
935 static int linker_init_done = 0 ;
937 #if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
938 static void *dl_prog_handle;
946 /* Make initLinker idempotent, so we can call it
947 before evey relevant operation; that means we
948 don't need to initialise the linker separately */
949 if (linker_init_done == 1) { return; } else {
950 linker_init_done = 1;
953 stablehash = allocStrHashTable();
954 symhash = allocStrHashTable();
956 /* populate the symbol table with stuff from the RTS */
957 for (sym = rtsSyms; sym->lbl != NULL; sym++) {
958 ghciInsertStrHashTable("(GHCi built-in symbols)",
959 symhash, sym->lbl, sym->addr);
961 # if defined(OBJFORMAT_MACHO) && defined(powerpc_HOST_ARCH)
962 machoInitSymbolsWithoutUnderscore();
965 # if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
966 # if defined(RTLD_DEFAULT)
967 dl_prog_handle = RTLD_DEFAULT;
969 dl_prog_handle = dlopen(NULL, RTLD_LAZY);
970 # endif /* RTLD_DEFAULT */
974 /* -----------------------------------------------------------------------------
975 * Loading DLL or .so dynamic libraries
976 * -----------------------------------------------------------------------------
978 * Add a DLL from which symbols may be found. In the ELF case, just
979 * do RTLD_GLOBAL-style add, so no further messing around needs to
980 * happen in order that symbols in the loaded .so are findable --
981 * lookupSymbol() will subsequently see them by dlsym on the program's
982 * dl-handle. Returns NULL if success, otherwise ptr to an err msg.
984 * In the PEi386 case, open the DLLs and put handles to them in a
985 * linked list. When looking for a symbol, try all handles in the
986 * list. This means that we need to load even DLLs that are guaranteed
987 * to be in the ghc.exe image already, just so we can get a handle
988 * to give to loadSymbol, so that we can find the symbols. For such
989 * libraries, the LoadLibrary call should be a no-op except for returning
994 #if defined(OBJFORMAT_PEi386)
995 /* A record for storing handles into DLLs. */
1000 struct _OpenedDLL* next;
1005 /* A list thereof. */
1006 static OpenedDLL* opened_dlls = NULL;
1010 addDLL( char *dll_name )
1012 # if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
1013 /* ------------------- ELF DLL loader ------------------- */
1019 hdl= dlopen(dll_name, RTLD_NOW | RTLD_GLOBAL);
1022 /* dlopen failed; return a ptr to the error msg. */
1024 if (errmsg == NULL) errmsg = "addDLL: unknown error";
1031 # elif defined(OBJFORMAT_PEi386)
1032 /* ------------------- Win32 DLL loader ------------------- */
1040 /* debugBelch("\naddDLL; dll_name = `%s'\n", dll_name); */
1042 /* See if we've already got it, and ignore if so. */
1043 for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
1044 if (0 == strcmp(o_dll->name, dll_name))
1048 /* The file name has no suffix (yet) so that we can try
1049 both foo.dll and foo.drv
1051 The documentation for LoadLibrary says:
1052 If no file name extension is specified in the lpFileName
1053 parameter, the default library extension .dll is
1054 appended. However, the file name string can include a trailing
1055 point character (.) to indicate that the module name has no
1058 buf = stgMallocBytes(strlen(dll_name) + 10, "addDLL");
1059 sprintf(buf, "%s.DLL", dll_name);
1060 instance = LoadLibrary(buf);
1061 if (instance == NULL) {
1062 sprintf(buf, "%s.DRV", dll_name); // KAA: allow loading of drivers (like winspool.drv)
1063 instance = LoadLibrary(buf);
1064 if (instance == NULL) {
1067 /* LoadLibrary failed; return a ptr to the error msg. */
1068 return "addDLL: unknown error";
1073 /* Add this DLL to the list of DLLs in which to search for symbols. */
1074 o_dll = stgMallocBytes( sizeof(OpenedDLL), "addDLL" );
1075 o_dll->name = stgMallocBytes(1+strlen(dll_name), "addDLL");
1076 strcpy(o_dll->name, dll_name);
1077 o_dll->instance = instance;
1078 o_dll->next = opened_dlls;
1079 opened_dlls = o_dll;
1083 barf("addDLL: not implemented on this platform");
1087 /* -----------------------------------------------------------------------------
1088 * insert a stable symbol in the hash table
1092 insertStableSymbol(char* obj_name, char* key, StgPtr p)
1094 ghciInsertStrHashTable(obj_name, stablehash, key, getStablePtr(p));
1098 /* -----------------------------------------------------------------------------
1099 * insert a symbol in the hash table
1102 insertSymbol(char* obj_name, char* key, void* data)
1104 ghciInsertStrHashTable(obj_name, symhash, key, data);
1107 /* -----------------------------------------------------------------------------
1108 * lookup a symbol in the hash table
1111 lookupSymbol( char *lbl )
1115 ASSERT(symhash != NULL);
1116 val = lookupStrHashTable(symhash, lbl);
1119 # if defined(OBJFORMAT_ELF)
1120 return dlsym(dl_prog_handle, lbl);
1121 # elif defined(OBJFORMAT_MACHO)
1123 /* On OS X 10.3 and later, we use dlsym instead of the old legacy
1126 HACK: On OS X, global symbols are prefixed with an underscore.
1127 However, dlsym wants us to omit the leading underscore from the
1128 symbol name. For now, we simply strip it off here (and ONLY
1131 ASSERT(lbl[0] == '_');
1132 return dlsym(dl_prog_handle, lbl+1);
1134 if(NSIsSymbolNameDefined(lbl)) {
1135 NSSymbol symbol = NSLookupAndBindSymbol(lbl);
1136 return NSAddressOfSymbol(symbol);
1140 # endif /* HAVE_DLFCN_H */
1141 # elif defined(OBJFORMAT_PEi386)
1144 for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
1145 /* debugBelch("look in %s for %s\n", o_dll->name, lbl); */
1146 if (lbl[0] == '_') {
1147 /* HACK: if the name has an initial underscore, try stripping
1148 it off & look that up first. I've yet to verify whether there's
1149 a Rule that governs whether an initial '_' *should always* be
1150 stripped off when mapping from import lib name to the DLL name.
1152 sym = GetProcAddress(o_dll->instance, (lbl+1));
1154 /*debugBelch("found %s in %s\n", lbl+1,o_dll->name);*/
1158 sym = GetProcAddress(o_dll->instance, lbl);
1160 /*debugBelch("found %s in %s\n", lbl,o_dll->name);*/
1175 __attribute((unused))
1177 lookupLocalSymbol( ObjectCode* oc, char *lbl )
1181 val = lookupStrHashTable(oc->lochash, lbl);
1191 /* -----------------------------------------------------------------------------
1192 * Debugging aid: look in GHCi's object symbol tables for symbols
1193 * within DELTA bytes of the specified address, and show their names.
1196 void ghci_enquire ( char* addr );
1198 void ghci_enquire ( char* addr )
1203 const int DELTA = 64;
1208 for (oc = objects; oc; oc = oc->next) {
1209 for (i = 0; i < oc->n_symbols; i++) {
1210 sym = oc->symbols[i];
1211 if (sym == NULL) continue;
1212 // debugBelch("enquire %p %p\n", sym, oc->lochash);
1214 if (oc->lochash != NULL) {
1215 a = lookupStrHashTable(oc->lochash, sym);
1218 a = lookupStrHashTable(symhash, sym);
1221 // debugBelch("ghci_enquire: can't find %s\n", sym);
1223 else if (addr-DELTA <= a && a <= addr+DELTA) {
1224 debugBelch("%p + %3d == `%s'\n", addr, (int)(a - addr), sym);
1231 #ifdef ia64_HOST_ARCH
1232 static unsigned int PLTSize(void);
1235 /* -----------------------------------------------------------------------------
1236 * Load an obj (populate the global symbol table, but don't resolve yet)
1238 * Returns: 1 if ok, 0 on error.
1241 loadObj( char *path )
1248 void *map_addr = NULL;
1254 /* debugBelch("loadObj %s\n", path ); */
1256 /* Check that we haven't already loaded this object.
1257 Ignore requests to load multiple times */
1261 for (o = objects; o; o = o->next) {
1262 if (0 == strcmp(o->fileName, path)) {
1264 break; /* don't need to search further */
1268 IF_DEBUG(linker, debugBelch(
1269 "GHCi runtime linker: warning: looks like you're trying to load the\n"
1270 "same object file twice:\n"
1272 "GHCi will ignore this, but be warned.\n"
1274 return 1; /* success */
1278 oc = stgMallocBytes(sizeof(ObjectCode), "loadObj(oc)");
1280 # if defined(OBJFORMAT_ELF)
1281 oc->formatName = "ELF";
1282 # elif defined(OBJFORMAT_PEi386)
1283 oc->formatName = "PEi386";
1284 # elif defined(OBJFORMAT_MACHO)
1285 oc->formatName = "Mach-O";
1288 barf("loadObj: not implemented on this platform");
1291 r = stat(path, &st);
1292 if (r == -1) { return 0; }
1294 /* sigh, strdup() isn't a POSIX function, so do it the long way */
1295 oc->fileName = stgMallocBytes( strlen(path)+1, "loadObj" );
1296 strcpy(oc->fileName, path);
1298 oc->fileSize = st.st_size;
1300 oc->sections = NULL;
1301 oc->lochash = allocStrHashTable();
1302 oc->proddables = NULL;
1304 /* chain it onto the list of objects */
1309 #define ROUND_UP(x,size) ((x + size - 1) & ~(size - 1))
1311 /* On many architectures malloc'd memory isn't executable, so we need to use mmap. */
1313 #if defined(openbsd_HOST_OS)
1314 fd = open(path, O_RDONLY, S_IRUSR);
1316 fd = open(path, O_RDONLY);
1319 barf("loadObj: can't open `%s'", path);
1321 pagesize = getpagesize();
1323 #ifdef ia64_HOST_ARCH
1324 /* The PLT needs to be right before the object */
1325 n = ROUND_UP(PLTSize(), pagesize);
1326 oc->plt = mmap(NULL, n, PROT_EXEC|PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
1327 if (oc->plt == MAP_FAILED)
1328 barf("loadObj: can't allocate PLT");
1331 map_addr = oc->plt + n;
1334 n = ROUND_UP(oc->fileSize, pagesize);
1336 /* Link objects into the lower 2Gb on x86_64. GHC assumes the
1337 * small memory model on this architecture (see gcc docs,
1340 * MAP_32BIT not available on OpenBSD/amd64
1342 #if defined(x86_64_HOST_ARCH) && defined(MAP_32BIT)
1343 #define EXTRA_MAP_FLAGS MAP_32BIT
1345 #define EXTRA_MAP_FLAGS 0
1348 /* MAP_ANONYMOUS is MAP_ANON on some systems, e.g. OpenBSD */
1349 #if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
1350 #define MAP_ANONYMOUS MAP_ANON
1353 oc->image = mmap(map_addr, n, PROT_EXEC|PROT_READ|PROT_WRITE,
1354 MAP_PRIVATE|EXTRA_MAP_FLAGS, fd, 0);
1355 if (oc->image == MAP_FAILED)
1356 barf("loadObj: can't map `%s'", path);
1360 #else /* !USE_MMAP */
1362 /* load the image into memory */
1363 f = fopen(path, "rb");
1365 barf("loadObj: can't read `%s'", path);
1367 # if defined(mingw32_HOST_OS)
1368 // TODO: We would like to use allocateExec here, but allocateExec
1369 // cannot currently allocate blocks large enough.
1370 oc->image = VirtualAlloc(NULL, oc->fileSize, MEM_RESERVE | MEM_COMMIT,
1371 PAGE_EXECUTE_READWRITE);
1372 # elif defined(darwin_HOST_OS)
1373 // In a Mach-O .o file, all sections can and will be misaligned
1374 // if the total size of the headers is not a multiple of the
1375 // desired alignment. This is fine for .o files that only serve
1376 // as input for the static linker, but it's not fine for us,
1377 // as SSE (used by gcc for floating point) and Altivec require
1378 // 16-byte alignment.
1379 // We calculate the correct alignment from the header before
1380 // reading the file, and then we misalign oc->image on purpose so
1381 // that the actual sections end up aligned again.
1382 oc->misalignment = machoGetMisalignment(f);
1383 oc->image = stgMallocBytes(oc->fileSize + oc->misalignment, "loadObj(image)");
1384 oc->image += oc->misalignment;
1386 oc->image = stgMallocBytes(oc->fileSize, "loadObj(image)");
1389 n = fread ( oc->image, 1, oc->fileSize, f );
1390 if (n != oc->fileSize)
1391 barf("loadObj: error whilst reading `%s'", path);
1394 #endif /* USE_MMAP */
1396 # if defined(OBJFORMAT_MACHO) && (defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH))
1397 r = ocAllocateSymbolExtras_MachO ( oc );
1398 if (!r) { return r; }
1399 # elif defined(OBJFORMAT_ELF) && (defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH))
1400 r = ocAllocateSymbolExtras_ELF ( oc );
1401 if (!r) { return r; }
1404 /* verify the in-memory image */
1405 # if defined(OBJFORMAT_ELF)
1406 r = ocVerifyImage_ELF ( oc );
1407 # elif defined(OBJFORMAT_PEi386)
1408 r = ocVerifyImage_PEi386 ( oc );
1409 # elif defined(OBJFORMAT_MACHO)
1410 r = ocVerifyImage_MachO ( oc );
1412 barf("loadObj: no verify method");
1414 if (!r) { return r; }
1416 /* build the symbol list for this image */
1417 # if defined(OBJFORMAT_ELF)
1418 r = ocGetNames_ELF ( oc );
1419 # elif defined(OBJFORMAT_PEi386)
1420 r = ocGetNames_PEi386 ( oc );
1421 # elif defined(OBJFORMAT_MACHO)
1422 r = ocGetNames_MachO ( oc );
1424 barf("loadObj: no getNames method");
1426 if (!r) { return r; }
1428 /* loaded, but not resolved yet */
1429 oc->status = OBJECT_LOADED;
1434 /* -----------------------------------------------------------------------------
1435 * resolve all the currently unlinked objects in memory
1437 * Returns: 1 if ok, 0 on error.
1447 for (oc = objects; oc; oc = oc->next) {
1448 if (oc->status != OBJECT_RESOLVED) {
1449 # if defined(OBJFORMAT_ELF)
1450 r = ocResolve_ELF ( oc );
1451 # elif defined(OBJFORMAT_PEi386)
1452 r = ocResolve_PEi386 ( oc );
1453 # elif defined(OBJFORMAT_MACHO)
1454 r = ocResolve_MachO ( oc );
1456 barf("resolveObjs: not implemented on this platform");
1458 if (!r) { return r; }
1459 oc->status = OBJECT_RESOLVED;
1465 /* -----------------------------------------------------------------------------
1466 * delete an object from the pool
1469 unloadObj( char *path )
1471 ObjectCode *oc, *prev;
1473 ASSERT(symhash != NULL);
1474 ASSERT(objects != NULL);
1479 for (oc = objects; oc; prev = oc, oc = oc->next) {
1480 if (!strcmp(oc->fileName,path)) {
1482 /* Remove all the mappings for the symbols within this
1487 for (i = 0; i < oc->n_symbols; i++) {
1488 if (oc->symbols[i] != NULL) {
1489 removeStrHashTable(symhash, oc->symbols[i], NULL);
1497 prev->next = oc->next;
1500 // We're going to leave this in place, in case there are
1501 // any pointers from the heap into it:
1502 // #ifdef mingw32_HOST_OS
1503 // VirtualFree(oc->image);
1505 // stgFree(oc->image);
1507 stgFree(oc->fileName);
1508 stgFree(oc->symbols);
1509 stgFree(oc->sections);
1510 /* The local hash table should have been freed at the end
1511 of the ocResolve_ call on it. */
1512 ASSERT(oc->lochash == NULL);
1518 errorBelch("unloadObj: can't find `%s' to unload", path);
1522 /* -----------------------------------------------------------------------------
1523 * Sanity checking. For each ObjectCode, maintain a list of address ranges
1524 * which may be prodded during relocation, and abort if we try and write
1525 * outside any of these.
1527 static void addProddableBlock ( ObjectCode* oc, void* start, int size )
1530 = stgMallocBytes(sizeof(ProddableBlock), "addProddableBlock");
1531 /* debugBelch("aPB %p %p %d\n", oc, start, size); */
1535 pb->next = oc->proddables;
1536 oc->proddables = pb;
1539 static void checkProddableBlock ( ObjectCode* oc, void* addr )
1542 for (pb = oc->proddables; pb != NULL; pb = pb->next) {
1543 char* s = (char*)(pb->start);
1544 char* e = s + pb->size - 1;
1545 char* a = (char*)addr;
1546 /* Assumes that the biggest fixup involves a 4-byte write. This
1547 probably needs to be changed to 8 (ie, +7) on 64-bit
1549 if (a >= s && (a+3) <= e) return;
1551 barf("checkProddableBlock: invalid fixup in runtime linker");
1554 /* -----------------------------------------------------------------------------
1555 * Section management.
1557 static void addSection ( ObjectCode* oc, SectionKind kind,
1558 void* start, void* end )
1560 Section* s = stgMallocBytes(sizeof(Section), "addSection");
1564 s->next = oc->sections;
1567 debugBelch("addSection: %p-%p (size %d), kind %d\n",
1568 start, ((char*)end)-1, end - start + 1, kind );
1573 /* --------------------------------------------------------------------------
1575 * This is about allocating a small chunk of memory for every symbol in the
1576 * object file. We make sure that the SymboLExtras are always "in range" of
1577 * limited-range PC-relative instructions on various platforms by allocating
1578 * them right next to the object code itself.
1581 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
1584 ocAllocateSymbolExtras
1586 Allocate additional space at the end of the object file image to make room
1587 for jump islands (powerpc, x86_64) and GOT entries (x86_64).
1589 PowerPC relative branch instructions have a 24 bit displacement field.
1590 As PPC code is always 4-byte-aligned, this yields a +-32MB range.
1591 If a particular imported symbol is outside this range, we have to redirect
1592 the jump to a short piece of new code that just loads the 32bit absolute
1593 address and jumps there.
1594 On x86_64, PC-relative jumps and PC-relative accesses to the GOT are limited
1597 This function just allocates space for one SymbolExtra for every
1598 undefined symbol in the object file. The code for the jump islands is
1599 filled in by makeSymbolExtra below.
1602 static int ocAllocateSymbolExtras( ObjectCode* oc, int count, int first )
1609 int misalignment = 0;
1610 #ifdef darwin_HOST_OS
1611 misalignment = oc->misalignment;
1617 // round up to the nearest 4
1618 aligned = (oc->fileSize + 3) & ~3;
1621 #ifndef linux_HOST_OS /* mremap is a linux extension */
1622 #error ocAllocateSymbolExtras doesnt want USE_MMAP to be defined
1625 pagesize = getpagesize();
1626 n = ROUND_UP( oc->fileSize, pagesize );
1627 m = ROUND_UP( aligned + sizeof (SymbolExtra) * count, pagesize );
1629 /* If we have a half-page-size file and map one page of it then
1630 * the part of the page after the size of the file remains accessible.
1631 * If, however, we map in 2 pages, the 2nd page is not accessible
1632 * and will give a "Bus Error" on access. To get around this, we check
1633 * if we need any extra pages for the jump islands and map them in
1634 * anonymously. We must check that we actually require extra pages
1635 * otherwise the attempt to mmap 0 pages of anonymous memory will
1641 /* The effect of this mremap() call is only the ensure that we have
1642 * a sufficient number of virtually contiguous pages. As returned from
1643 * mremap, the pages past the end of the file are not backed. We give
1644 * them a backing by using MAP_FIXED to map in anonymous pages.
1646 oc->image = mremap( oc->image, n, m, MREMAP_MAYMOVE );
1648 if( oc->image == MAP_FAILED )
1650 errorBelch( "Unable to mremap for Jump Islands\n" );
1654 if( mmap( oc->image + n, m - n, PROT_READ | PROT_WRITE | PROT_EXEC,
1655 MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, 0, 0 ) == MAP_FAILED )
1657 errorBelch( "Unable to mmap( MAP_FIXED ) for Jump Islands\n" );
1663 oc->image -= misalignment;
1664 oc->image = stgReallocBytes( oc->image,
1666 aligned + sizeof (SymbolExtra) * count,
1667 "ocAllocateSymbolExtras" );
1668 oc->image += misalignment;
1669 #endif /* USE_MMAP */
1671 oc->symbol_extras = (SymbolExtra *) (oc->image + aligned);
1672 memset( oc->symbol_extras, 0, sizeof (SymbolExtra) * count );
1675 oc->symbol_extras = NULL;
1677 oc->first_symbol_extra = first;
1678 oc->n_symbol_extras = count;
1683 static SymbolExtra* makeSymbolExtra( ObjectCode* oc,
1684 unsigned long symbolNumber,
1685 unsigned long target )
1689 ASSERT( symbolNumber >= oc->first_symbol_extra
1690 && symbolNumber - oc->first_symbol_extra < oc->n_symbol_extras);
1692 extra = &oc->symbol_extras[symbolNumber - oc->first_symbol_extra];
1694 #ifdef powerpc_HOST_ARCH
1695 // lis r12, hi16(target)
1696 extra->jumpIsland.lis_r12 = 0x3d80;
1697 extra->jumpIsland.hi_addr = target >> 16;
1699 // ori r12, r12, lo16(target)
1700 extra->jumpIsland.ori_r12_r12 = 0x618c;
1701 extra->jumpIsland.lo_addr = target & 0xffff;
1704 extra->jumpIsland.mtctr_r12 = 0x7d8903a6;
1707 extra->jumpIsland.bctr = 0x4e800420;
1709 #ifdef x86_64_HOST_ARCH
1711 static uint8_t jmp[] = { 0xFF, 0x25, 0xF2, 0xFF, 0xFF, 0xFF };
1712 extra->addr = target;
1713 memcpy(extra->jumpIsland, jmp, 6);
1721 /* --------------------------------------------------------------------------
1722 * PowerPC specifics (instruction cache flushing)
1723 * ------------------------------------------------------------------------*/
1725 #ifdef powerpc_TARGET_ARCH
1727 ocFlushInstructionCache
1729 Flush the data & instruction caches.
1730 Because the PPC has split data/instruction caches, we have to
1731 do that whenever we modify code at runtime.
1734 static void ocFlushInstructionCache( ObjectCode *oc )
1736 int n = (oc->fileSize + sizeof( SymbolExtra ) * oc->n_symbol_extras + 3) / 4;
1737 unsigned long *p = (unsigned long *) oc->image;
1741 __asm__ volatile ( "dcbf 0,%0\n\t"
1749 __asm__ volatile ( "sync\n\t"
1755 /* --------------------------------------------------------------------------
1756 * PEi386 specifics (Win32 targets)
1757 * ------------------------------------------------------------------------*/
1759 /* The information for this linker comes from
1760 Microsoft Portable Executable
1761 and Common Object File Format Specification
1762 revision 5.1 January 1998
1763 which SimonM says comes from the MS Developer Network CDs.
1765 It can be found there (on older CDs), but can also be found
1768 http://www.microsoft.com/hwdev/hardware/PECOFF.asp
1770 (this is Rev 6.0 from February 1999).
1772 Things move, so if that fails, try searching for it via
1774 http://www.google.com/search?q=PE+COFF+specification
1776 The ultimate reference for the PE format is the Winnt.h
1777 header file that comes with the Platform SDKs; as always,
1778 implementations will drift wrt their documentation.
1780 A good background article on the PE format is Matt Pietrek's
1781 March 1994 article in Microsoft System Journal (MSJ)
1782 (Vol.9, No. 3): "Peering Inside the PE: A Tour of the
1783 Win32 Portable Executable File Format." The info in there
1784 has recently been updated in a two part article in
1785 MSDN magazine, issues Feb and March 2002,
1786 "Inside Windows: An In-Depth Look into the Win32 Portable
1787 Executable File Format"
1789 John Levine's book "Linkers and Loaders" contains useful
1794 #if defined(OBJFORMAT_PEi386)
1798 typedef unsigned char UChar;
1799 typedef unsigned short UInt16;
1800 typedef unsigned int UInt32;
1807 UInt16 NumberOfSections;
1808 UInt32 TimeDateStamp;
1809 UInt32 PointerToSymbolTable;
1810 UInt32 NumberOfSymbols;
1811 UInt16 SizeOfOptionalHeader;
1812 UInt16 Characteristics;
1816 #define sizeof_COFF_header 20
1823 UInt32 VirtualAddress;
1824 UInt32 SizeOfRawData;
1825 UInt32 PointerToRawData;
1826 UInt32 PointerToRelocations;
1827 UInt32 PointerToLinenumbers;
1828 UInt16 NumberOfRelocations;
1829 UInt16 NumberOfLineNumbers;
1830 UInt32 Characteristics;
1834 #define sizeof_COFF_section 40
1841 UInt16 SectionNumber;
1844 UChar NumberOfAuxSymbols;
1848 #define sizeof_COFF_symbol 18
1853 UInt32 VirtualAddress;
1854 UInt32 SymbolTableIndex;
1859 #define sizeof_COFF_reloc 10
1862 /* From PE spec doc, section 3.3.2 */
1863 /* Note use of MYIMAGE_* since IMAGE_* are already defined in
1864 windows.h -- for the same purpose, but I want to know what I'm
1866 #define MYIMAGE_FILE_RELOCS_STRIPPED 0x0001
1867 #define MYIMAGE_FILE_EXECUTABLE_IMAGE 0x0002
1868 #define MYIMAGE_FILE_DLL 0x2000
1869 #define MYIMAGE_FILE_SYSTEM 0x1000
1870 #define MYIMAGE_FILE_BYTES_REVERSED_HI 0x8000
1871 #define MYIMAGE_FILE_BYTES_REVERSED_LO 0x0080
1872 #define MYIMAGE_FILE_32BIT_MACHINE 0x0100
1874 /* From PE spec doc, section 5.4.2 and 5.4.4 */
1875 #define MYIMAGE_SYM_CLASS_EXTERNAL 2
1876 #define MYIMAGE_SYM_CLASS_STATIC 3
1877 #define MYIMAGE_SYM_UNDEFINED 0
1879 /* From PE spec doc, section 4.1 */
1880 #define MYIMAGE_SCN_CNT_CODE 0x00000020
1881 #define MYIMAGE_SCN_CNT_INITIALIZED_DATA 0x00000040
1882 #define MYIMAGE_SCN_LNK_NRELOC_OVFL 0x01000000
1884 /* From PE spec doc, section 5.2.1 */
1885 #define MYIMAGE_REL_I386_DIR32 0x0006
1886 #define MYIMAGE_REL_I386_REL32 0x0014
1889 /* We use myindex to calculate array addresses, rather than
1890 simply doing the normal subscript thing. That's because
1891 some of the above structs have sizes which are not
1892 a whole number of words. GCC rounds their sizes up to a
1893 whole number of words, which means that the address calcs
1894 arising from using normal C indexing or pointer arithmetic
1895 are just plain wrong. Sigh.
1898 myindex ( int scale, void* base, int index )
1901 ((UChar*)base) + scale * index;
1906 printName ( UChar* name, UChar* strtab )
1908 if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1909 UInt32 strtab_offset = * (UInt32*)(name+4);
1910 debugBelch("%s", strtab + strtab_offset );
1913 for (i = 0; i < 8; i++) {
1914 if (name[i] == 0) break;
1915 debugBelch("%c", name[i] );
1922 copyName ( UChar* name, UChar* strtab, UChar* dst, int dstSize )
1924 if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1925 UInt32 strtab_offset = * (UInt32*)(name+4);
1926 strncpy ( dst, strtab+strtab_offset, dstSize );
1932 if (name[i] == 0) break;
1942 cstring_from_COFF_symbol_name ( UChar* name, UChar* strtab )
1945 /* If the string is longer than 8 bytes, look in the
1946 string table for it -- this will be correctly zero terminated.
1948 if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1949 UInt32 strtab_offset = * (UInt32*)(name+4);
1950 return ((UChar*)strtab) + strtab_offset;
1952 /* Otherwise, if shorter than 8 bytes, return the original,
1953 which by defn is correctly terminated.
1955 if (name[7]==0) return name;
1956 /* The annoying case: 8 bytes. Copy into a temporary
1957 (which is never freed ...)
1959 newstr = stgMallocBytes(9, "cstring_from_COFF_symbol_name");
1961 strncpy(newstr,name,8);
1967 /* Just compares the short names (first 8 chars) */
1968 static COFF_section *
1969 findPEi386SectionCalled ( ObjectCode* oc, char* name )
1973 = (COFF_header*)(oc->image);
1974 COFF_section* sectab
1976 ((UChar*)(oc->image))
1977 + sizeof_COFF_header + hdr->SizeOfOptionalHeader
1979 for (i = 0; i < hdr->NumberOfSections; i++) {
1982 COFF_section* section_i
1984 myindex ( sizeof_COFF_section, sectab, i );
1985 n1 = (UChar*) &(section_i->Name);
1987 if (n1[0]==n2[0] && n1[1]==n2[1] && n1[2]==n2[2] &&
1988 n1[3]==n2[3] && n1[4]==n2[4] && n1[5]==n2[5] &&
1989 n1[6]==n2[6] && n1[7]==n2[7])
1998 zapTrailingAtSign ( UChar* sym )
2000 # define my_isdigit(c) ((c) >= '0' && (c) <= '9')
2002 if (sym[0] == 0) return;
2004 while (sym[i] != 0) i++;
2007 while (j > 0 && my_isdigit(sym[j])) j--;
2008 if (j > 0 && sym[j] == '@' && j != i) sym[j] = 0;
2014 ocVerifyImage_PEi386 ( ObjectCode* oc )
2019 COFF_section* sectab;
2020 COFF_symbol* symtab;
2022 /* debugBelch("\nLOADING %s\n", oc->fileName); */
2023 hdr = (COFF_header*)(oc->image);
2024 sectab = (COFF_section*) (
2025 ((UChar*)(oc->image))
2026 + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2028 symtab = (COFF_symbol*) (
2029 ((UChar*)(oc->image))
2030 + hdr->PointerToSymbolTable
2032 strtab = ((UChar*)symtab)
2033 + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2035 if (hdr->Machine != 0x14c) {
2036 errorBelch("%s: Not x86 PEi386", oc->fileName);
2039 if (hdr->SizeOfOptionalHeader != 0) {
2040 errorBelch("%s: PEi386 with nonempty optional header", oc->fileName);
2043 if ( /* (hdr->Characteristics & MYIMAGE_FILE_RELOCS_STRIPPED) || */
2044 (hdr->Characteristics & MYIMAGE_FILE_EXECUTABLE_IMAGE) ||
2045 (hdr->Characteristics & MYIMAGE_FILE_DLL) ||
2046 (hdr->Characteristics & MYIMAGE_FILE_SYSTEM) ) {
2047 errorBelch("%s: Not a PEi386 object file", oc->fileName);
2050 if ( (hdr->Characteristics & MYIMAGE_FILE_BYTES_REVERSED_HI)
2051 /* || !(hdr->Characteristics & MYIMAGE_FILE_32BIT_MACHINE) */ ) {
2052 errorBelch("%s: Invalid PEi386 word size or endiannness: %d",
2054 (int)(hdr->Characteristics));
2057 /* If the string table size is way crazy, this might indicate that
2058 there are more than 64k relocations, despite claims to the
2059 contrary. Hence this test. */
2060 /* debugBelch("strtab size %d\n", * (UInt32*)strtab); */
2062 if ( (*(UInt32*)strtab) > 600000 ) {
2063 /* Note that 600k has no special significance other than being
2064 big enough to handle the almost-2MB-sized lumps that
2065 constitute HSwin32*.o. */
2066 debugBelch("PEi386 object has suspiciously large string table; > 64k relocs?");
2071 /* No further verification after this point; only debug printing. */
2073 IF_DEBUG(linker, i=1);
2074 if (i == 0) return 1;
2076 debugBelch( "sectab offset = %d\n", ((UChar*)sectab) - ((UChar*)hdr) );
2077 debugBelch( "symtab offset = %d\n", ((UChar*)symtab) - ((UChar*)hdr) );
2078 debugBelch( "strtab offset = %d\n", ((UChar*)strtab) - ((UChar*)hdr) );
2081 debugBelch( "Machine: 0x%x\n", (UInt32)(hdr->Machine) );
2082 debugBelch( "# sections: %d\n", (UInt32)(hdr->NumberOfSections) );
2083 debugBelch( "time/date: 0x%x\n", (UInt32)(hdr->TimeDateStamp) );
2084 debugBelch( "symtab offset: %d\n", (UInt32)(hdr->PointerToSymbolTable) );
2085 debugBelch( "# symbols: %d\n", (UInt32)(hdr->NumberOfSymbols) );
2086 debugBelch( "sz of opt hdr: %d\n", (UInt32)(hdr->SizeOfOptionalHeader) );
2087 debugBelch( "characteristics: 0x%x\n", (UInt32)(hdr->Characteristics) );
2089 /* Print the section table. */
2091 for (i = 0; i < hdr->NumberOfSections; i++) {
2093 COFF_section* sectab_i
2095 myindex ( sizeof_COFF_section, sectab, i );
2102 printName ( sectab_i->Name, strtab );
2112 sectab_i->VirtualSize,
2113 sectab_i->VirtualAddress,
2114 sectab_i->SizeOfRawData,
2115 sectab_i->PointerToRawData,
2116 sectab_i->NumberOfRelocations,
2117 sectab_i->PointerToRelocations,
2118 sectab_i->PointerToRawData
2120 reltab = (COFF_reloc*) (
2121 ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
2124 if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
2125 /* If the relocation field (a short) has overflowed, the
2126 * real count can be found in the first reloc entry.
2128 * See Section 4.1 (last para) of the PE spec (rev6.0).
2130 COFF_reloc* rel = (COFF_reloc*)
2131 myindex ( sizeof_COFF_reloc, reltab, 0 );
2132 noRelocs = rel->VirtualAddress;
2135 noRelocs = sectab_i->NumberOfRelocations;
2139 for (; j < noRelocs; j++) {
2141 COFF_reloc* rel = (COFF_reloc*)
2142 myindex ( sizeof_COFF_reloc, reltab, j );
2144 " type 0x%-4x vaddr 0x%-8x name `",
2146 rel->VirtualAddress );
2147 sym = (COFF_symbol*)
2148 myindex ( sizeof_COFF_symbol, symtab, rel->SymbolTableIndex );
2149 /* Hmm..mysterious looking offset - what's it for? SOF */
2150 printName ( sym->Name, strtab -10 );
2157 debugBelch("string table has size 0x%x\n", * (UInt32*)strtab );
2158 debugBelch("---START of string table---\n");
2159 for (i = 4; i < *(Int32*)strtab; i++) {
2161 debugBelch("\n"); else
2162 debugBelch("%c", strtab[i] );
2164 debugBelch("--- END of string table---\n");
2169 COFF_symbol* symtab_i;
2170 if (i >= (Int32)(hdr->NumberOfSymbols)) break;
2171 symtab_i = (COFF_symbol*)
2172 myindex ( sizeof_COFF_symbol, symtab, i );
2178 printName ( symtab_i->Name, strtab );
2187 (Int32)(symtab_i->SectionNumber),
2188 (UInt32)symtab_i->Type,
2189 (UInt32)symtab_i->StorageClass,
2190 (UInt32)symtab_i->NumberOfAuxSymbols
2192 i += symtab_i->NumberOfAuxSymbols;
2202 ocGetNames_PEi386 ( ObjectCode* oc )
2205 COFF_section* sectab;
2206 COFF_symbol* symtab;
2213 hdr = (COFF_header*)(oc->image);
2214 sectab = (COFF_section*) (
2215 ((UChar*)(oc->image))
2216 + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2218 symtab = (COFF_symbol*) (
2219 ((UChar*)(oc->image))
2220 + hdr->PointerToSymbolTable
2222 strtab = ((UChar*)(oc->image))
2223 + hdr->PointerToSymbolTable
2224 + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2226 /* Allocate space for any (local, anonymous) .bss sections. */
2228 for (i = 0; i < hdr->NumberOfSections; i++) {
2231 COFF_section* sectab_i
2233 myindex ( sizeof_COFF_section, sectab, i );
2234 if (0 != strcmp(sectab_i->Name, ".bss")) continue;
2235 /* sof 10/05: the PE spec text isn't too clear regarding what
2236 * the SizeOfRawData field is supposed to hold for object
2237 * file sections containing just uninitialized data -- for executables,
2238 * it is supposed to be zero; unclear what it's supposed to be
2239 * for object files. However, VirtualSize is guaranteed to be
2240 * zero for object files, which definitely suggests that SizeOfRawData
2241 * will be non-zero (where else would the size of this .bss section be
2242 * stored?) Looking at the COFF_section info for incoming object files,
2243 * this certainly appears to be the case.
2245 * => I suspect we've been incorrectly handling .bss sections in (relocatable)
2246 * object files up until now. This turned out to bite us with ghc-6.4.1's use
2247 * of gcc-3.4.x, which has started to emit initially-zeroed-out local 'static'
2248 * variable decls into to the .bss section. (The specific function in Q which
2249 * triggered this is libraries/base/cbits/dirUtils.c:__hscore_getFolderPath())
2251 if (sectab_i->VirtualSize == 0 && sectab_i->SizeOfRawData == 0) continue;
2252 /* This is a non-empty .bss section. Allocate zeroed space for
2253 it, and set its PointerToRawData field such that oc->image +
2254 PointerToRawData == addr_of_zeroed_space. */
2255 bss_sz = sectab_i->VirtualSize;
2256 if ( bss_sz < sectab_i->SizeOfRawData) { bss_sz = sectab_i->SizeOfRawData; }
2257 zspace = stgCallocBytes(1, bss_sz, "ocGetNames_PEi386(anonymous bss)");
2258 sectab_i->PointerToRawData = ((UChar*)zspace) - ((UChar*)(oc->image));
2259 addProddableBlock(oc, zspace, bss_sz);
2260 /* debugBelch("BSS anon section at 0x%x\n", zspace); */
2263 /* Copy section information into the ObjectCode. */
2265 for (i = 0; i < hdr->NumberOfSections; i++) {
2271 = SECTIONKIND_OTHER;
2272 COFF_section* sectab_i
2274 myindex ( sizeof_COFF_section, sectab, i );
2275 IF_DEBUG(linker, debugBelch("section name = %s\n", sectab_i->Name ));
2278 /* I'm sure this is the Right Way to do it. However, the
2279 alternative of testing the sectab_i->Name field seems to
2280 work ok with Cygwin.
2282 if (sectab_i->Characteristics & MYIMAGE_SCN_CNT_CODE ||
2283 sectab_i->Characteristics & MYIMAGE_SCN_CNT_INITIALIZED_DATA)
2284 kind = SECTIONKIND_CODE_OR_RODATA;
2287 if (0==strcmp(".text",sectab_i->Name) ||
2288 0==strcmp(".rdata",sectab_i->Name)||
2289 0==strcmp(".rodata",sectab_i->Name))
2290 kind = SECTIONKIND_CODE_OR_RODATA;
2291 if (0==strcmp(".data",sectab_i->Name) ||
2292 0==strcmp(".bss",sectab_i->Name))
2293 kind = SECTIONKIND_RWDATA;
2295 ASSERT(sectab_i->SizeOfRawData == 0 || sectab_i->VirtualSize == 0);
2296 sz = sectab_i->SizeOfRawData;
2297 if (sz < sectab_i->VirtualSize) sz = sectab_i->VirtualSize;
2299 start = ((UChar*)(oc->image)) + sectab_i->PointerToRawData;
2300 end = start + sz - 1;
2302 if (kind == SECTIONKIND_OTHER
2303 /* Ignore sections called which contain stabs debugging
2305 && 0 != strcmp(".stab", sectab_i->Name)
2306 && 0 != strcmp(".stabstr", sectab_i->Name)
2307 /* ignore constructor section for now */
2308 && 0 != strcmp(".ctors", sectab_i->Name)
2309 /* ignore section generated from .ident */
2310 && 0!= strcmp("/4", sectab_i->Name)
2311 /* ignore unknown section that appeared in gcc 3.4.5(?) */
2312 && 0!= strcmp(".reloc", sectab_i->Name)
2314 errorBelch("Unknown PEi386 section name `%s' (while processing: %s)", sectab_i->Name, oc->fileName);
2318 if (kind != SECTIONKIND_OTHER && end >= start) {
2319 addSection(oc, kind, start, end);
2320 addProddableBlock(oc, start, end - start + 1);
2324 /* Copy exported symbols into the ObjectCode. */
2326 oc->n_symbols = hdr->NumberOfSymbols;
2327 oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
2328 "ocGetNames_PEi386(oc->symbols)");
2329 /* Call me paranoid; I don't care. */
2330 for (i = 0; i < oc->n_symbols; i++)
2331 oc->symbols[i] = NULL;
2335 COFF_symbol* symtab_i;
2336 if (i >= (Int32)(hdr->NumberOfSymbols)) break;
2337 symtab_i = (COFF_symbol*)
2338 myindex ( sizeof_COFF_symbol, symtab, i );
2342 if (symtab_i->StorageClass == MYIMAGE_SYM_CLASS_EXTERNAL
2343 && symtab_i->SectionNumber != MYIMAGE_SYM_UNDEFINED) {
2344 /* This symbol is global and defined, viz, exported */
2345 /* for MYIMAGE_SYMCLASS_EXTERNAL
2346 && !MYIMAGE_SYM_UNDEFINED,
2347 the address of the symbol is:
2348 address of relevant section + offset in section
2350 COFF_section* sectabent
2351 = (COFF_section*) myindex ( sizeof_COFF_section,
2353 symtab_i->SectionNumber-1 );
2354 addr = ((UChar*)(oc->image))
2355 + (sectabent->PointerToRawData
2359 if (symtab_i->SectionNumber == MYIMAGE_SYM_UNDEFINED
2360 && symtab_i->Value > 0) {
2361 /* This symbol isn't in any section at all, ie, global bss.
2362 Allocate zeroed space for it. */
2363 addr = stgCallocBytes(1, symtab_i->Value,
2364 "ocGetNames_PEi386(non-anonymous bss)");
2365 addSection(oc, SECTIONKIND_RWDATA, addr,
2366 ((UChar*)addr) + symtab_i->Value - 1);
2367 addProddableBlock(oc, addr, symtab_i->Value);
2368 /* debugBelch("BSS section at 0x%x\n", addr); */
2371 if (addr != NULL ) {
2372 sname = cstring_from_COFF_symbol_name ( symtab_i->Name, strtab );
2373 /* debugBelch("addSymbol %p `%s \n", addr,sname); */
2374 IF_DEBUG(linker, debugBelch("addSymbol %p `%s'\n", addr,sname);)
2375 ASSERT(i >= 0 && i < oc->n_symbols);
2376 /* cstring_from_COFF_symbol_name always succeeds. */
2377 oc->symbols[i] = sname;
2378 ghciInsertStrHashTable(oc->fileName, symhash, sname, addr);
2382 "IGNORING symbol %d\n"
2386 printName ( symtab_i->Name, strtab );
2395 (Int32)(symtab_i->SectionNumber),
2396 (UInt32)symtab_i->Type,
2397 (UInt32)symtab_i->StorageClass,
2398 (UInt32)symtab_i->NumberOfAuxSymbols
2403 i += symtab_i->NumberOfAuxSymbols;
2412 ocResolve_PEi386 ( ObjectCode* oc )
2415 COFF_section* sectab;
2416 COFF_symbol* symtab;
2426 /* ToDo: should be variable-sized? But is at least safe in the
2427 sense of buffer-overrun-proof. */
2429 /* debugBelch("resolving for %s\n", oc->fileName); */
2431 hdr = (COFF_header*)(oc->image);
2432 sectab = (COFF_section*) (
2433 ((UChar*)(oc->image))
2434 + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2436 symtab = (COFF_symbol*) (
2437 ((UChar*)(oc->image))
2438 + hdr->PointerToSymbolTable
2440 strtab = ((UChar*)(oc->image))
2441 + hdr->PointerToSymbolTable
2442 + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2444 for (i = 0; i < hdr->NumberOfSections; i++) {
2445 COFF_section* sectab_i
2447 myindex ( sizeof_COFF_section, sectab, i );
2450 ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
2453 /* Ignore sections called which contain stabs debugging
2455 if (0 == strcmp(".stab", sectab_i->Name)
2456 || 0 == strcmp(".stabstr", sectab_i->Name)
2457 || 0 == strcmp(".ctors", sectab_i->Name))
2460 if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
2461 /* If the relocation field (a short) has overflowed, the
2462 * real count can be found in the first reloc entry.
2464 * See Section 4.1 (last para) of the PE spec (rev6.0).
2466 * Nov2003 update: the GNU linker still doesn't correctly
2467 * handle the generation of relocatable object files with
2468 * overflown relocations. Hence the output to warn of potential
2471 COFF_reloc* rel = (COFF_reloc*)
2472 myindex ( sizeof_COFF_reloc, reltab, 0 );
2473 noRelocs = rel->VirtualAddress;
2475 /* 10/05: we now assume (and check for) a GNU ld that is capable
2476 * of handling object files with (>2^16) of relocs.
2479 debugBelch("WARNING: Overflown relocation field (# relocs found: %u)\n",
2484 noRelocs = sectab_i->NumberOfRelocations;
2489 for (; j < noRelocs; j++) {
2491 COFF_reloc* reltab_j
2493 myindex ( sizeof_COFF_reloc, reltab, j );
2495 /* the location to patch */
2497 ((UChar*)(oc->image))
2498 + (sectab_i->PointerToRawData
2499 + reltab_j->VirtualAddress
2500 - sectab_i->VirtualAddress )
2502 /* the existing contents of pP */
2504 /* the symbol to connect to */
2505 sym = (COFF_symbol*)
2506 myindex ( sizeof_COFF_symbol,
2507 symtab, reltab_j->SymbolTableIndex );
2510 "reloc sec %2d num %3d: type 0x%-4x "
2511 "vaddr 0x%-8x name `",
2513 (UInt32)reltab_j->Type,
2514 reltab_j->VirtualAddress );
2515 printName ( sym->Name, strtab );
2516 debugBelch("'\n" ));
2518 if (sym->StorageClass == MYIMAGE_SYM_CLASS_STATIC) {
2519 COFF_section* section_sym
2520 = findPEi386SectionCalled ( oc, sym->Name );
2522 errorBelch("%s: can't find section `%s'", oc->fileName, sym->Name);
2525 S = ((UInt32)(oc->image))
2526 + (section_sym->PointerToRawData
2529 copyName ( sym->Name, strtab, symbol, 1000-1 );
2530 S = (UInt32) lookupLocalSymbol( oc, symbol );
2531 if ((void*)S != NULL) goto foundit;
2532 S = (UInt32) lookupSymbol( symbol );
2533 if ((void*)S != NULL) goto foundit;
2534 zapTrailingAtSign ( symbol );
2535 S = (UInt32) lookupLocalSymbol( oc, symbol );
2536 if ((void*)S != NULL) goto foundit;
2537 S = (UInt32) lookupSymbol( symbol );
2538 if ((void*)S != NULL) goto foundit;
2539 /* Newline first because the interactive linker has printed "linking..." */
2540 errorBelch("\n%s: unknown symbol `%s'", oc->fileName, symbol);
2544 checkProddableBlock(oc, pP);
2545 switch (reltab_j->Type) {
2546 case MYIMAGE_REL_I386_DIR32:
2549 case MYIMAGE_REL_I386_REL32:
2550 /* Tricky. We have to insert a displacement at
2551 pP which, when added to the PC for the _next_
2552 insn, gives the address of the target (S).
2553 Problem is to know the address of the next insn
2554 when we only know pP. We assume that this
2555 literal field is always the last in the insn,
2556 so that the address of the next insn is pP+4
2557 -- hence the constant 4.
2558 Also I don't know if A should be added, but so
2559 far it has always been zero.
2561 SOF 05/2005: 'A' (old contents of *pP) have been observed
2562 to contain values other than zero (the 'wx' object file
2563 that came with wxhaskell-0.9.4; dunno how it was compiled..).
2564 So, add displacement to old value instead of asserting
2565 A to be zero. Fixes wxhaskell-related crashes, and no other
2566 ill effects have been observed.
2568 Update: the reason why we're seeing these more elaborate
2569 relocations is due to a switch in how the NCG compiles SRTs
2570 and offsets to them from info tables. SRTs live in .(ro)data,
2571 while info tables live in .text, causing GAS to emit REL32/DISP32
2572 relocations with non-zero values. Adding the displacement is
2573 the right thing to do.
2575 *pP = S - ((UInt32)pP) - 4 + A;
2578 debugBelch("%s: unhandled PEi386 relocation type %d",
2579 oc->fileName, reltab_j->Type);
2586 IF_DEBUG(linker, debugBelch("completed %s", oc->fileName));
2590 #endif /* defined(OBJFORMAT_PEi386) */
2593 /* --------------------------------------------------------------------------
2595 * ------------------------------------------------------------------------*/
2597 #if defined(OBJFORMAT_ELF)
2602 #if defined(sparc_HOST_ARCH)
2603 # define ELF_TARGET_SPARC /* Used inside <elf.h> */
2604 #elif defined(i386_HOST_ARCH)
2605 # define ELF_TARGET_386 /* Used inside <elf.h> */
2606 #elif defined(x86_64_HOST_ARCH)
2607 # define ELF_TARGET_X64_64
2609 #elif defined (ia64_HOST_ARCH)
2610 # define ELF_TARGET_IA64 /* Used inside <elf.h> */
2612 # define ELF_FUNCTION_DESC /* calling convention uses function descriptors */
2613 # define ELF_NEED_GOT /* needs Global Offset Table */
2614 # define ELF_NEED_PLT /* needs Procedure Linkage Tables */
2617 #if !defined(openbsd_HOST_OS)
2620 /* openbsd elf has things in different places, with diff names */
2621 # include <elf_abi.h>
2622 # include <machine/reloc.h>
2623 # define R_386_32 RELOC_32
2624 # define R_386_PC32 RELOC_PC32
2627 /* If elf.h doesn't define it */
2628 # ifndef R_X86_64_PC64
2629 # define R_X86_64_PC64 24
2633 * Define a set of types which can be used for both ELF32 and ELF64
2637 #define ELFCLASS ELFCLASS64
2638 #define Elf_Addr Elf64_Addr
2639 #define Elf_Word Elf64_Word
2640 #define Elf_Sword Elf64_Sword
2641 #define Elf_Ehdr Elf64_Ehdr
2642 #define Elf_Phdr Elf64_Phdr
2643 #define Elf_Shdr Elf64_Shdr
2644 #define Elf_Sym Elf64_Sym
2645 #define Elf_Rel Elf64_Rel
2646 #define Elf_Rela Elf64_Rela
2647 #define ELF_ST_TYPE ELF64_ST_TYPE
2648 #define ELF_ST_BIND ELF64_ST_BIND
2649 #define ELF_R_TYPE ELF64_R_TYPE
2650 #define ELF_R_SYM ELF64_R_SYM
2652 #define ELFCLASS ELFCLASS32
2653 #define Elf_Addr Elf32_Addr
2654 #define Elf_Word Elf32_Word
2655 #define Elf_Sword Elf32_Sword
2656 #define Elf_Ehdr Elf32_Ehdr
2657 #define Elf_Phdr Elf32_Phdr
2658 #define Elf_Shdr Elf32_Shdr
2659 #define Elf_Sym Elf32_Sym
2660 #define Elf_Rel Elf32_Rel
2661 #define Elf_Rela Elf32_Rela
2663 #define ELF_ST_TYPE ELF32_ST_TYPE
2666 #define ELF_ST_BIND ELF32_ST_BIND
2669 #define ELF_R_TYPE ELF32_R_TYPE
2672 #define ELF_R_SYM ELF32_R_SYM
2678 * Functions to allocate entries in dynamic sections. Currently we simply
2679 * preallocate a large number, and we don't check if a entry for the given
2680 * target already exists (a linear search is too slow). Ideally these
2681 * entries would be associated with symbols.
2684 /* These sizes sufficient to load HSbase + HShaskell98 + a few modules */
2685 #define GOT_SIZE 0x20000
2686 #define FUNCTION_TABLE_SIZE 0x10000
2687 #define PLT_SIZE 0x08000
2690 static Elf_Addr got[GOT_SIZE];
2691 static unsigned int gotIndex;
2692 static Elf_Addr gp_val = (Elf_Addr)got;
2695 allocateGOTEntry(Elf_Addr target)
2699 if (gotIndex >= GOT_SIZE)
2700 barf("Global offset table overflow");
2702 entry = &got[gotIndex++];
2704 return (Elf_Addr)entry;
2708 #ifdef ELF_FUNCTION_DESC
2714 static FunctionDesc functionTable[FUNCTION_TABLE_SIZE];
2715 static unsigned int functionTableIndex;
2718 allocateFunctionDesc(Elf_Addr target)
2720 FunctionDesc *entry;
2722 if (functionTableIndex >= FUNCTION_TABLE_SIZE)
2723 barf("Function table overflow");
2725 entry = &functionTable[functionTableIndex++];
2727 entry->gp = (Elf_Addr)gp_val;
2728 return (Elf_Addr)entry;
2732 copyFunctionDesc(Elf_Addr target)
2734 FunctionDesc *olddesc = (FunctionDesc *)target;
2735 FunctionDesc *newdesc;
2737 newdesc = (FunctionDesc *)allocateFunctionDesc(olddesc->ip);
2738 newdesc->gp = olddesc->gp;
2739 return (Elf_Addr)newdesc;
2744 #ifdef ia64_HOST_ARCH
2745 static void ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value);
2746 static void ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc);
2748 static unsigned char plt_code[] =
2750 /* taken from binutils bfd/elfxx-ia64.c */
2751 0x0b, 0x78, 0x00, 0x02, 0x00, 0x24, /* [MMI] addl r15=0,r1;; */
2752 0x00, 0x41, 0x3c, 0x30, 0x28, 0xc0, /* ld8 r16=[r15],8 */
2753 0x01, 0x08, 0x00, 0x84, /* mov r14=r1;; */
2754 0x11, 0x08, 0x00, 0x1e, 0x18, 0x10, /* [MIB] ld8 r1=[r15] */
2755 0x60, 0x80, 0x04, 0x80, 0x03, 0x00, /* mov b6=r16 */
2756 0x60, 0x00, 0x80, 0x00 /* br.few b6;; */
2759 /* If we can't get to the function descriptor via gp, take a local copy of it */
2760 #define PLT_RELOC(code, target) { \
2761 Elf64_Sxword rel_value = target - gp_val; \
2762 if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff)) \
2763 ia64_reloc_gprel22((Elf_Addr)code, copyFunctionDesc(target)); \
2765 ia64_reloc_gprel22((Elf_Addr)code, target); \
2770 unsigned char code[sizeof(plt_code)];
2774 allocatePLTEntry(Elf_Addr target, ObjectCode *oc)
2776 PLTEntry *plt = (PLTEntry *)oc->plt;
2779 if (oc->pltIndex >= PLT_SIZE)
2780 barf("Procedure table overflow");
2782 entry = &plt[oc->pltIndex++];
2783 memcpy(entry->code, plt_code, sizeof(entry->code));
2784 PLT_RELOC(entry->code, target);
2785 return (Elf_Addr)entry;
2791 return (PLT_SIZE * sizeof(PLTEntry));
2797 * Generic ELF functions
2801 findElfSection ( void* objImage, Elf_Word sh_type )
2803 char* ehdrC = (char*)objImage;
2804 Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2805 Elf_Shdr* shdr = (Elf_Shdr*)(ehdrC + ehdr->e_shoff);
2806 char* sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
2810 for (i = 0; i < ehdr->e_shnum; i++) {
2811 if (shdr[i].sh_type == sh_type
2812 /* Ignore the section header's string table. */
2813 && i != ehdr->e_shstrndx
2814 /* Ignore string tables named .stabstr, as they contain
2816 && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
2818 ptr = ehdrC + shdr[i].sh_offset;
2825 #if defined(ia64_HOST_ARCH)
2827 findElfSegment ( void* objImage, Elf_Addr vaddr )
2829 char* ehdrC = (char*)objImage;
2830 Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2831 Elf_Phdr* phdr = (Elf_Phdr*)(ehdrC + ehdr->e_phoff);
2832 Elf_Addr segaddr = 0;
2835 for (i = 0; i < ehdr->e_phnum; i++) {
2836 segaddr = phdr[i].p_vaddr;
2837 if ((vaddr >= segaddr) && (vaddr < segaddr + phdr[i].p_memsz))
2845 ocVerifyImage_ELF ( ObjectCode* oc )
2849 int i, j, nent, nstrtab, nsymtabs;
2853 char* ehdrC = (char*)(oc->image);
2854 Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2856 if (ehdr->e_ident[EI_MAG0] != ELFMAG0 ||
2857 ehdr->e_ident[EI_MAG1] != ELFMAG1 ||
2858 ehdr->e_ident[EI_MAG2] != ELFMAG2 ||
2859 ehdr->e_ident[EI_MAG3] != ELFMAG3) {
2860 errorBelch("%s: not an ELF object", oc->fileName);
2864 if (ehdr->e_ident[EI_CLASS] != ELFCLASS) {
2865 errorBelch("%s: unsupported ELF format", oc->fileName);
2869 if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) {
2870 IF_DEBUG(linker,debugBelch( "Is little-endian\n" ));
2872 if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) {
2873 IF_DEBUG(linker,debugBelch( "Is big-endian\n" ));
2875 errorBelch("%s: unknown endiannness", oc->fileName);
2879 if (ehdr->e_type != ET_REL) {
2880 errorBelch("%s: not a relocatable object (.o) file", oc->fileName);
2883 IF_DEBUG(linker, debugBelch( "Is a relocatable object (.o) file\n" ));
2885 IF_DEBUG(linker,debugBelch( "Architecture is " ));
2886 switch (ehdr->e_machine) {
2887 case EM_386: IF_DEBUG(linker,debugBelch( "x86" )); break;
2888 #ifdef EM_SPARC32PLUS
2889 case EM_SPARC32PLUS:
2891 case EM_SPARC: IF_DEBUG(linker,debugBelch( "sparc" )); break;
2893 case EM_IA_64: IF_DEBUG(linker,debugBelch( "ia64" )); break;
2895 case EM_PPC: IF_DEBUG(linker,debugBelch( "powerpc32" )); break;
2897 case EM_X86_64: IF_DEBUG(linker,debugBelch( "x86_64" )); break;
2898 #elif defined(EM_AMD64)
2899 case EM_AMD64: IF_DEBUG(linker,debugBelch( "amd64" )); break;
2901 default: IF_DEBUG(linker,debugBelch( "unknown" ));
2902 errorBelch("%s: unknown architecture (e_machine == %d)"
2903 , oc->fileName, ehdr->e_machine);
2907 IF_DEBUG(linker,debugBelch(
2908 "\nSection header table: start %ld, n_entries %d, ent_size %d\n",
2909 (long)ehdr->e_shoff, ehdr->e_shnum, ehdr->e_shentsize ));
2911 ASSERT (ehdr->e_shentsize == sizeof(Elf_Shdr));
2913 shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
2915 if (ehdr->e_shstrndx == SHN_UNDEF) {
2916 errorBelch("%s: no section header string table", oc->fileName);
2919 IF_DEBUG(linker,debugBelch( "Section header string table is section %d\n",
2921 sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
2924 for (i = 0; i < ehdr->e_shnum; i++) {
2925 IF_DEBUG(linker,debugBelch("%2d: ", i ));
2926 IF_DEBUG(linker,debugBelch("type=%2d ", (int)shdr[i].sh_type ));
2927 IF_DEBUG(linker,debugBelch("size=%4d ", (int)shdr[i].sh_size ));
2928 IF_DEBUG(linker,debugBelch("offs=%4d ", (int)shdr[i].sh_offset ));
2929 IF_DEBUG(linker,debugBelch(" (%p .. %p) ",
2930 ehdrC + shdr[i].sh_offset,
2931 ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1));
2933 if (shdr[i].sh_type == SHT_REL) {
2934 IF_DEBUG(linker,debugBelch("Rel " ));
2935 } else if (shdr[i].sh_type == SHT_RELA) {
2936 IF_DEBUG(linker,debugBelch("RelA " ));
2938 IF_DEBUG(linker,debugBelch(" "));
2941 IF_DEBUG(linker,debugBelch("sname=%s\n", sh_strtab + shdr[i].sh_name ));
2945 IF_DEBUG(linker,debugBelch( "\nString tables" ));
2948 for (i = 0; i < ehdr->e_shnum; i++) {
2949 if (shdr[i].sh_type == SHT_STRTAB
2950 /* Ignore the section header's string table. */
2951 && i != ehdr->e_shstrndx
2952 /* Ignore string tables named .stabstr, as they contain
2954 && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
2956 IF_DEBUG(linker,debugBelch(" section %d is a normal string table", i ));
2957 strtab = ehdrC + shdr[i].sh_offset;
2962 errorBelch("%s: no string tables, or too many", oc->fileName);
2967 IF_DEBUG(linker,debugBelch( "\nSymbol tables" ));
2968 for (i = 0; i < ehdr->e_shnum; i++) {
2969 if (shdr[i].sh_type != SHT_SYMTAB) continue;
2970 IF_DEBUG(linker,debugBelch( "section %d is a symbol table\n", i ));
2972 stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
2973 nent = shdr[i].sh_size / sizeof(Elf_Sym);
2974 IF_DEBUG(linker,debugBelch( " number of entries is apparently %d (%ld rem)\n",
2976 (long)shdr[i].sh_size % sizeof(Elf_Sym)
2978 if (0 != shdr[i].sh_size % sizeof(Elf_Sym)) {
2979 errorBelch("%s: non-integral number of symbol table entries", oc->fileName);
2982 for (j = 0; j < nent; j++) {
2983 IF_DEBUG(linker,debugBelch(" %2d ", j ));
2984 IF_DEBUG(linker,debugBelch(" sec=%-5d size=%-3d val=%5p ",
2985 (int)stab[j].st_shndx,
2986 (int)stab[j].st_size,
2987 (char*)stab[j].st_value ));
2989 IF_DEBUG(linker,debugBelch("type=" ));
2990 switch (ELF_ST_TYPE(stab[j].st_info)) {
2991 case STT_NOTYPE: IF_DEBUG(linker,debugBelch("notype " )); break;
2992 case STT_OBJECT: IF_DEBUG(linker,debugBelch("object " )); break;
2993 case STT_FUNC : IF_DEBUG(linker,debugBelch("func " )); break;
2994 case STT_SECTION: IF_DEBUG(linker,debugBelch("section" )); break;
2995 case STT_FILE: IF_DEBUG(linker,debugBelch("file " )); break;
2996 default: IF_DEBUG(linker,debugBelch("? " )); break;
2998 IF_DEBUG(linker,debugBelch(" " ));
3000 IF_DEBUG(linker,debugBelch("bind=" ));
3001 switch (ELF_ST_BIND(stab[j].st_info)) {
3002 case STB_LOCAL : IF_DEBUG(linker,debugBelch("local " )); break;
3003 case STB_GLOBAL: IF_DEBUG(linker,debugBelch("global" )); break;
3004 case STB_WEAK : IF_DEBUG(linker,debugBelch("weak " )); break;
3005 default: IF_DEBUG(linker,debugBelch("? " )); break;
3007 IF_DEBUG(linker,debugBelch(" " ));
3009 IF_DEBUG(linker,debugBelch("name=%s\n", strtab + stab[j].st_name ));
3013 if (nsymtabs == 0) {
3014 errorBelch("%s: didn't find any symbol tables", oc->fileName);
3021 static int getSectionKind_ELF( Elf_Shdr *hdr, int *is_bss )
3025 if (hdr->sh_type == SHT_PROGBITS
3026 && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_EXECINSTR)) {
3027 /* .text-style section */
3028 return SECTIONKIND_CODE_OR_RODATA;
3031 if (hdr->sh_type == SHT_PROGBITS
3032 && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
3033 /* .data-style section */
3034 return SECTIONKIND_RWDATA;
3037 if (hdr->sh_type == SHT_PROGBITS
3038 && (hdr->sh_flags & SHF_ALLOC) && !(hdr->sh_flags & SHF_WRITE)) {
3039 /* .rodata-style section */
3040 return SECTIONKIND_CODE_OR_RODATA;
3043 if (hdr->sh_type == SHT_NOBITS
3044 && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
3045 /* .bss-style section */
3047 return SECTIONKIND_RWDATA;
3050 return SECTIONKIND_OTHER;
3055 ocGetNames_ELF ( ObjectCode* oc )
3060 char* ehdrC = (char*)(oc->image);
3061 Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
3062 char* strtab = findElfSection ( ehdrC, SHT_STRTAB );
3063 Elf_Shdr* shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
3065 ASSERT(symhash != NULL);
3068 errorBelch("%s: no strtab", oc->fileName);
3073 for (i = 0; i < ehdr->e_shnum; i++) {
3074 /* Figure out what kind of section it is. Logic derived from
3075 Figure 1.14 ("Special Sections") of the ELF document
3076 ("Portable Formats Specification, Version 1.1"). */
3078 SectionKind kind = getSectionKind_ELF(&shdr[i], &is_bss);
3080 if (is_bss && shdr[i].sh_size > 0) {
3081 /* This is a non-empty .bss section. Allocate zeroed space for
3082 it, and set its .sh_offset field such that
3083 ehdrC + .sh_offset == addr_of_zeroed_space. */
3084 char* zspace = stgCallocBytes(1, shdr[i].sh_size,
3085 "ocGetNames_ELF(BSS)");
3086 shdr[i].sh_offset = ((char*)zspace) - ((char*)ehdrC);
3088 debugBelch("BSS section at 0x%x, size %d\n",
3089 zspace, shdr[i].sh_size);
3093 /* fill in the section info */
3094 if (kind != SECTIONKIND_OTHER && shdr[i].sh_size > 0) {
3095 addProddableBlock(oc, ehdrC + shdr[i].sh_offset, shdr[i].sh_size);
3096 addSection(oc, kind, ehdrC + shdr[i].sh_offset,
3097 ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1);
3100 if (shdr[i].sh_type != SHT_SYMTAB) continue;
3102 /* copy stuff into this module's object symbol table */
3103 stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
3104 nent = shdr[i].sh_size / sizeof(Elf_Sym);
3106 oc->n_symbols = nent;
3107 oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
3108 "ocGetNames_ELF(oc->symbols)");
3110 for (j = 0; j < nent; j++) {
3112 char isLocal = FALSE; /* avoids uninit-var warning */
3114 char* nm = strtab + stab[j].st_name;
3115 int secno = stab[j].st_shndx;
3117 /* Figure out if we want to add it; if so, set ad to its
3118 address. Otherwise leave ad == NULL. */
3120 if (secno == SHN_COMMON) {
3122 ad = stgCallocBytes(1, stab[j].st_size, "ocGetNames_ELF(COMMON)");
3124 debugBelch("COMMON symbol, size %d name %s\n",
3125 stab[j].st_size, nm);
3127 /* Pointless to do addProddableBlock() for this area,
3128 since the linker should never poke around in it. */
3131 if ( ( ELF_ST_BIND(stab[j].st_info)==STB_GLOBAL
3132 || ELF_ST_BIND(stab[j].st_info)==STB_LOCAL
3134 /* and not an undefined symbol */
3135 && stab[j].st_shndx != SHN_UNDEF
3136 /* and not in a "special section" */
3137 && stab[j].st_shndx < SHN_LORESERVE
3139 /* and it's a not a section or string table or anything silly */
3140 ( ELF_ST_TYPE(stab[j].st_info)==STT_FUNC ||
3141 ELF_ST_TYPE(stab[j].st_info)==STT_OBJECT ||
3142 ELF_ST_TYPE(stab[j].st_info)==STT_NOTYPE
3145 /* Section 0 is the undefined section, hence > and not >=. */
3146 ASSERT(secno > 0 && secno < ehdr->e_shnum);
3148 if (shdr[secno].sh_type == SHT_NOBITS) {
3149 debugBelch(" BSS symbol, size %d off %d name %s\n",
3150 stab[j].st_size, stab[j].st_value, nm);
3153 ad = ehdrC + shdr[ secno ].sh_offset + stab[j].st_value;
3154 if (ELF_ST_BIND(stab[j].st_info)==STB_LOCAL) {
3157 #ifdef ELF_FUNCTION_DESC
3158 /* dlsym() and the initialisation table both give us function
3159 * descriptors, so to be consistent we store function descriptors
3160 * in the symbol table */
3161 if (ELF_ST_TYPE(stab[j].st_info) == STT_FUNC)
3162 ad = (char *)allocateFunctionDesc((Elf_Addr)ad);
3164 IF_DEBUG(linker,debugBelch( "addOTabName(GLOB): %10p %s %s",
3165 ad, oc->fileName, nm ));
3170 /* And the decision is ... */
3174 oc->symbols[j] = nm;
3177 /* Ignore entirely. */
3179 ghciInsertStrHashTable(oc->fileName, symhash, nm, ad);
3183 IF_DEBUG(linker,debugBelch( "skipping `%s'\n",
3184 strtab + stab[j].st_name ));
3187 "skipping bind = %d, type = %d, shndx = %d `%s'\n",
3188 (int)ELF_ST_BIND(stab[j].st_info),
3189 (int)ELF_ST_TYPE(stab[j].st_info),
3190 (int)stab[j].st_shndx,
3191 strtab + stab[j].st_name
3194 oc->symbols[j] = NULL;
3203 /* Do ELF relocations which lack an explicit addend. All x86-linux
3204 relocations appear to be of this form. */
3206 do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
3207 Elf_Shdr* shdr, int shnum,
3208 Elf_Sym* stab, char* strtab )
3213 Elf_Rel* rtab = (Elf_Rel*) (ehdrC + shdr[shnum].sh_offset);
3214 int nent = shdr[shnum].sh_size / sizeof(Elf_Rel);
3215 int target_shndx = shdr[shnum].sh_info;
3216 int symtab_shndx = shdr[shnum].sh_link;
3218 stab = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
3219 targ = (Elf_Word*)(ehdrC + shdr[ target_shndx ].sh_offset);
3220 IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
3221 target_shndx, symtab_shndx ));
3223 /* Skip sections that we're not interested in. */
3226 SectionKind kind = getSectionKind_ELF(&shdr[target_shndx], &is_bss);
3227 if (kind == SECTIONKIND_OTHER) {
3228 IF_DEBUG(linker,debugBelch( "skipping (target section not loaded)"));
3233 for (j = 0; j < nent; j++) {
3234 Elf_Addr offset = rtab[j].r_offset;
3235 Elf_Addr info = rtab[j].r_info;
3237 Elf_Addr P = ((Elf_Addr)targ) + offset;
3238 Elf_Word* pP = (Elf_Word*)P;
3243 StgStablePtr stablePtr;
3246 IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p)",
3247 j, (void*)offset, (void*)info ));
3249 IF_DEBUG(linker,debugBelch( " ZERO" ));
3252 Elf_Sym sym = stab[ELF_R_SYM(info)];
3253 /* First see if it is a local symbol. */
3254 if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
3255 /* Yes, so we can get the address directly from the ELF symbol
3257 symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
3259 (ehdrC + shdr[ sym.st_shndx ].sh_offset
3260 + stab[ELF_R_SYM(info)].st_value);
3263 symbol = strtab + sym.st_name;
3264 stablePtr = (StgStablePtr)lookupHashTable(stablehash, (StgWord)symbol);
3265 if (NULL == stablePtr) {
3266 /* No, so look up the name in our global table. */
3267 S_tmp = lookupSymbol( symbol );
3268 S = (Elf_Addr)S_tmp;
3270 stableVal = deRefStablePtr( stablePtr );
3272 S = (Elf_Addr)S_tmp;
3276 errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
3279 IF_DEBUG(linker,debugBelch( "`%s' resolves to %p\n", symbol, (void*)S ));
3282 IF_DEBUG(linker,debugBelch( "Reloc: P = %p S = %p A = %p\n",
3283 (void*)P, (void*)S, (void*)A ));
3284 checkProddableBlock ( oc, pP );
3288 switch (ELF_R_TYPE(info)) {
3289 # ifdef i386_HOST_ARCH
3290 case R_386_32: *pP = value; break;
3291 case R_386_PC32: *pP = value - P; break;
3294 errorBelch("%s: unhandled ELF relocation(Rel) type %lu\n",
3295 oc->fileName, (lnat)ELF_R_TYPE(info));
3303 /* Do ELF relocations for which explicit addends are supplied.
3304 sparc-solaris relocations appear to be of this form. */
3306 do_Elf_Rela_relocations ( ObjectCode* oc, char* ehdrC,
3307 Elf_Shdr* shdr, int shnum,
3308 Elf_Sym* stab, char* strtab )
3311 char *symbol = NULL;
3313 Elf_Rela* rtab = (Elf_Rela*) (ehdrC + shdr[shnum].sh_offset);
3314 int nent = shdr[shnum].sh_size / sizeof(Elf_Rela);
3315 int target_shndx = shdr[shnum].sh_info;
3316 int symtab_shndx = shdr[shnum].sh_link;
3318 stab = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
3319 targ = (Elf_Addr) (ehdrC + shdr[ target_shndx ].sh_offset);
3320 IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
3321 target_shndx, symtab_shndx ));
3323 for (j = 0; j < nent; j++) {
3324 #if defined(DEBUG) || defined(sparc_HOST_ARCH) || defined(ia64_HOST_ARCH) || defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
3325 /* This #ifdef only serves to avoid unused-var warnings. */
3326 Elf_Addr offset = rtab[j].r_offset;
3327 Elf_Addr P = targ + offset;
3329 Elf_Addr info = rtab[j].r_info;
3330 Elf_Addr A = rtab[j].r_addend;
3334 # if defined(sparc_HOST_ARCH)
3335 Elf_Word* pP = (Elf_Word*)P;
3337 # elif defined(ia64_HOST_ARCH)
3338 Elf64_Xword *pP = (Elf64_Xword *)P;
3340 # elif defined(powerpc_HOST_ARCH)
3344 IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p %6p) ",
3345 j, (void*)offset, (void*)info,
3348 IF_DEBUG(linker,debugBelch( " ZERO" ));
3351 Elf_Sym sym = stab[ELF_R_SYM(info)];
3352 /* First see if it is a local symbol. */
3353 if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
3354 /* Yes, so we can get the address directly from the ELF symbol
3356 symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
3358 (ehdrC + shdr[ sym.st_shndx ].sh_offset
3359 + stab[ELF_R_SYM(info)].st_value);
3360 #ifdef ELF_FUNCTION_DESC
3361 /* Make a function descriptor for this function */
3362 if (S && ELF_ST_TYPE(sym.st_info) == STT_FUNC) {
3363 S = allocateFunctionDesc(S + A);
3368 /* No, so look up the name in our global table. */
3369 symbol = strtab + sym.st_name;
3370 S_tmp = lookupSymbol( symbol );
3371 S = (Elf_Addr)S_tmp;
3373 #ifdef ELF_FUNCTION_DESC
3374 /* If a function, already a function descriptor - we would
3375 have to copy it to add an offset. */
3376 if (S && (ELF_ST_TYPE(sym.st_info) == STT_FUNC) && (A != 0))
3377 errorBelch("%s: function %s with addend %p", oc->fileName, symbol, (void *)A);
3381 errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
3384 IF_DEBUG(linker,debugBelch( "`%s' resolves to %p", symbol, (void*)S ));
3387 IF_DEBUG(linker,debugBelch("Reloc: P = %p S = %p A = %p\n",
3388 (void*)P, (void*)S, (void*)A ));
3389 /* checkProddableBlock ( oc, (void*)P ); */
3393 switch (ELF_R_TYPE(info)) {
3394 # if defined(sparc_HOST_ARCH)
3395 case R_SPARC_WDISP30:
3396 w1 = *pP & 0xC0000000;
3397 w2 = (Elf_Word)((value - P) >> 2);
3398 ASSERT((w2 & 0xC0000000) == 0);
3403 w1 = *pP & 0xFFC00000;
3404 w2 = (Elf_Word)(value >> 10);
3405 ASSERT((w2 & 0xFFC00000) == 0);
3411 w2 = (Elf_Word)(value & 0x3FF);
3412 ASSERT((w2 & ~0x3FF) == 0);
3416 /* According to the Sun documentation:
3418 This relocation type resembles R_SPARC_32, except it refers to an
3419 unaligned word. That is, the word to be relocated must be treated
3420 as four separate bytes with arbitrary alignment, not as a word
3421 aligned according to the architecture requirements.
3423 (JRS: which means that freeloading on the R_SPARC_32 case
3424 is probably wrong, but hey ...)
3428 w2 = (Elf_Word)value;
3431 # elif defined(ia64_HOST_ARCH)
3432 case R_IA64_DIR64LSB:
3433 case R_IA64_FPTR64LSB:
3436 case R_IA64_PCREL64LSB:
3439 case R_IA64_SEGREL64LSB:
3440 addr = findElfSegment(ehdrC, value);
3443 case R_IA64_GPREL22:
3444 ia64_reloc_gprel22(P, value);
3446 case R_IA64_LTOFF22:
3447 case R_IA64_LTOFF22X:
3448 case R_IA64_LTOFF_FPTR22:
3449 addr = allocateGOTEntry(value);
3450 ia64_reloc_gprel22(P, addr);
3452 case R_IA64_PCREL21B:
3453 ia64_reloc_pcrel21(P, S, oc);
3456 /* This goes with R_IA64_LTOFF22X and points to the load to
3457 * convert into a move. We don't implement relaxation. */
3459 # elif defined(powerpc_HOST_ARCH)
3460 case R_PPC_ADDR16_LO:
3461 *(Elf32_Half*) P = value;
3464 case R_PPC_ADDR16_HI:
3465 *(Elf32_Half*) P = value >> 16;
3468 case R_PPC_ADDR16_HA:
3469 *(Elf32_Half*) P = (value + 0x8000) >> 16;
3473 *(Elf32_Word *) P = value;
3477 *(Elf32_Word *) P = value - P;
3483 if( delta << 6 >> 6 != delta )
3485 value = (Elf_Addr) (&makeSymbolExtra( oc, ELF_R_SYM(info), value )
3489 if( value == 0 || delta << 6 >> 6 != delta )
3491 barf( "Unable to make SymbolExtra for #%d",
3497 *(Elf_Word *) P = (*(Elf_Word *) P & 0xfc000003)
3498 | (delta & 0x3fffffc);
3502 #if x86_64_HOST_ARCH
3504 *(Elf64_Xword *)P = value;
3509 StgInt64 off = value - P;
3510 if (off >= 0x7fffffffL || off < -0x80000000L) {
3511 #if X86_64_ELF_NONPIC_HACK
3512 StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3514 off = pltAddress + A - P;
3516 barf("R_X86_64_PC32 relocation out of range: %s = %p\nRecompile %s with -fPIC.",
3517 symbol, off, oc->fileName );
3520 *(Elf64_Word *)P = (Elf64_Word)off;
3526 StgInt64 off = value - P;
3527 *(Elf64_Word *)P = (Elf64_Word)off;
3532 if (value >= 0x7fffffffL) {
3533 #if X86_64_ELF_NONPIC_HACK
3534 StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3536 value = pltAddress + A;
3538 barf("R_X86_64_32 relocation out of range: %s = %p\nRecompile %s with -fPIC.",
3539 symbol, value, oc->fileName );
3542 *(Elf64_Word *)P = (Elf64_Word)value;
3546 if ((StgInt64)value > 0x7fffffffL || (StgInt64)value < -0x80000000L) {
3547 #if X86_64_ELF_NONPIC_HACK
3548 StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3550 value = pltAddress + A;
3552 barf("R_X86_64_32S relocation out of range: %s = %p\nRecompile %s with -fPIC.",
3553 symbol, value, oc->fileName );
3556 *(Elf64_Sword *)P = (Elf64_Sword)value;
3559 case R_X86_64_GOTPCREL:
3561 StgInt64 gotAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)->addr;
3562 StgInt64 off = gotAddress + A - P;
3563 *(Elf64_Word *)P = (Elf64_Word)off;
3567 case R_X86_64_PLT32:
3569 StgInt64 off = value - P;
3570 if (off >= 0x7fffffffL || off < -0x80000000L) {
3571 StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3573 off = pltAddress + A - P;
3575 *(Elf64_Word *)P = (Elf64_Word)off;
3581 errorBelch("%s: unhandled ELF relocation(RelA) type %lu\n",
3582 oc->fileName, (lnat)ELF_R_TYPE(info));
3591 ocResolve_ELF ( ObjectCode* oc )
3595 Elf_Sym* stab = NULL;
3596 char* ehdrC = (char*)(oc->image);
3597 Elf_Ehdr* ehdr = (Elf_Ehdr*) ehdrC;
3598 Elf_Shdr* shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
3600 /* first find "the" symbol table */
3601 stab = (Elf_Sym*) findElfSection ( ehdrC, SHT_SYMTAB );
3603 /* also go find the string table */
3604 strtab = findElfSection ( ehdrC, SHT_STRTAB );
3606 if (stab == NULL || strtab == NULL) {
3607 errorBelch("%s: can't find string or symbol table", oc->fileName);
3611 /* Process the relocation sections. */
3612 for (shnum = 0; shnum < ehdr->e_shnum; shnum++) {
3613 if (shdr[shnum].sh_type == SHT_REL) {
3614 ok = do_Elf_Rel_relocations ( oc, ehdrC, shdr,
3615 shnum, stab, strtab );
3619 if (shdr[shnum].sh_type == SHT_RELA) {
3620 ok = do_Elf_Rela_relocations ( oc, ehdrC, shdr,
3621 shnum, stab, strtab );
3626 /* Free the local symbol table; we won't need it again. */
3627 freeHashTable(oc->lochash, NULL);
3630 #if defined(powerpc_HOST_ARCH)
3631 ocFlushInstructionCache( oc );
3639 * Instructions are 41 bits long, packed into 128 bit bundles with a 5-bit template
3640 * at the front. The following utility functions pack and unpack instructions, and
3641 * take care of the most common relocations.
3644 #ifdef ia64_HOST_ARCH
3647 ia64_extract_instruction(Elf64_Xword *target)
3650 int slot = (Elf_Addr)target & 3;
3651 target = (Elf_Addr)target & ~3;
3659 return ((w1 >> 5) & 0x1ffffffffff);
3661 return (w1 >> 46) | ((w2 & 0x7fffff) << 18);
3665 barf("ia64_extract_instruction: invalid slot %p", target);
3670 ia64_deposit_instruction(Elf64_Xword *target, Elf64_Xword value)
3672 int slot = (Elf_Addr)target & 3;
3673 target = (Elf_Addr)target & ~3;
3678 *target |= value << 5;
3681 *target |= value << 46;
3682 *(target+1) |= value >> 18;
3685 *(target+1) |= value << 23;
3691 ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value)
3693 Elf64_Xword instruction;
3694 Elf64_Sxword rel_value;
3696 rel_value = value - gp_val;
3697 if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff))
3698 barf("GP-relative data out of range (address = 0x%lx, gp = 0x%lx)", value, gp_val);
3700 instruction = ia64_extract_instruction((Elf64_Xword *)target);
3701 instruction |= (((rel_value >> 0) & 0x07f) << 13) /* imm7b */
3702 | (((rel_value >> 7) & 0x1ff) << 27) /* imm9d */
3703 | (((rel_value >> 16) & 0x01f) << 22) /* imm5c */
3704 | ((Elf64_Xword)(rel_value < 0) << 36); /* s */
3705 ia64_deposit_instruction((Elf64_Xword *)target, instruction);
3709 ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc)
3711 Elf64_Xword instruction;
3712 Elf64_Sxword rel_value;
3715 entry = allocatePLTEntry(value, oc);
3717 rel_value = (entry >> 4) - (target >> 4);
3718 if ((rel_value > 0xfffff) || (rel_value < -0xfffff))
3719 barf("PLT entry too far away (entry = 0x%lx, target = 0x%lx)", entry, target);
3721 instruction = ia64_extract_instruction((Elf64_Xword *)target);
3722 instruction |= ((rel_value & 0xfffff) << 13) /* imm20b */
3723 | ((Elf64_Xword)(rel_value < 0) << 36); /* s */
3724 ia64_deposit_instruction((Elf64_Xword *)target, instruction);
3730 * PowerPC & X86_64 ELF specifics
3733 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
3735 static int ocAllocateSymbolExtras_ELF( ObjectCode *oc )
3741 ehdr = (Elf_Ehdr *) oc->image;
3742 shdr = (Elf_Shdr *) ( ((char *)oc->image) + ehdr->e_shoff );
3744 for( i = 0; i < ehdr->e_shnum; i++ )
3745 if( shdr[i].sh_type == SHT_SYMTAB )
3748 if( i == ehdr->e_shnum )
3750 errorBelch( "This ELF file contains no symtab" );
3754 if( shdr[i].sh_entsize != sizeof( Elf_Sym ) )
3756 errorBelch( "The entry size (%d) of the symtab isn't %d\n",
3757 (int) shdr[i].sh_entsize, (int) sizeof( Elf_Sym ) );
3762 return ocAllocateSymbolExtras( oc, shdr[i].sh_size / sizeof( Elf_Sym ), 0 );
3765 #endif /* powerpc */
3769 /* --------------------------------------------------------------------------
3771 * ------------------------------------------------------------------------*/
3773 #if defined(OBJFORMAT_MACHO)
3776 Support for MachO linking on Darwin/MacOS X
3777 by Wolfgang Thaller (wolfgang.thaller@gmx.net)
3779 I hereby formally apologize for the hackish nature of this code.
3780 Things that need to be done:
3781 *) implement ocVerifyImage_MachO
3782 *) add still more sanity checks.
3785 #if x86_64_HOST_ARCH || powerpc64_HOST_ARCH
3786 #define mach_header mach_header_64
3787 #define segment_command segment_command_64
3788 #define section section_64
3789 #define nlist nlist_64
3792 #ifdef powerpc_HOST_ARCH
3793 static int ocAllocateSymbolExtras_MachO(ObjectCode* oc)
3795 struct mach_header *header = (struct mach_header *) oc->image;
3796 struct load_command *lc = (struct load_command *) (header + 1);
3799 for( i = 0; i < header->ncmds; i++ )
3801 if( lc->cmd == LC_SYMTAB )
3803 // Find out the first and last undefined external
3804 // symbol, so we don't have to allocate too many
3806 struct symtab_command *symLC = (struct symtab_command *) lc;
3807 unsigned min = symLC->nsyms, max = 0;
3808 struct nlist *nlist =
3809 symLC ? (struct nlist*) ((char*) oc->image + symLC->symoff)
3811 for(i=0;i<symLC->nsyms;i++)
3813 if(nlist[i].n_type & N_STAB)
3815 else if(nlist[i].n_type & N_EXT)
3817 if((nlist[i].n_type & N_TYPE) == N_UNDF
3818 && (nlist[i].n_value == 0))
3828 return ocAllocateSymbolExtras(oc, max - min + 1, min);
3833 lc = (struct load_command *) ( ((char *)lc) + lc->cmdsize );
3835 return ocAllocateSymbolExtras(oc,0,0);
3838 #ifdef x86_64_HOST_ARCH
3839 static int ocAllocateSymbolExtras_MachO(ObjectCode* oc)
3841 struct mach_header *header = (struct mach_header *) oc->image;
3842 struct load_command *lc = (struct load_command *) (header + 1);
3845 for( i = 0; i < header->ncmds; i++ )
3847 if( lc->cmd == LC_SYMTAB )
3849 // Just allocate one entry for every symbol
3850 struct symtab_command *symLC = (struct symtab_command *) lc;
3852 return ocAllocateSymbolExtras(oc, symLC->nsyms, 0);
3855 lc = (struct load_command *) ( ((char *)lc) + lc->cmdsize );
3857 return ocAllocateSymbolExtras(oc,0,0);
3861 static int ocVerifyImage_MachO(ObjectCode* oc)
3863 char *image = (char*) oc->image;
3864 struct mach_header *header = (struct mach_header*) image;
3866 #if x86_64_TARGET_ARCH || powerpc64_TARGET_ARCH
3867 if(header->magic != MH_MAGIC_64)
3870 if(header->magic != MH_MAGIC)
3873 // FIXME: do some more verifying here
3877 static int resolveImports(
3880 struct symtab_command *symLC,
3881 struct section *sect, // ptr to lazy or non-lazy symbol pointer section
3882 unsigned long *indirectSyms,
3883 struct nlist *nlist)
3886 size_t itemSize = 4;
3889 int isJumpTable = 0;
3890 if(!strcmp(sect->sectname,"__jump_table"))
3894 ASSERT(sect->reserved2 == itemSize);
3898 for(i=0; i*itemSize < sect->size;i++)
3900 // according to otool, reserved1 contains the first index into the indirect symbol table
3901 struct nlist *symbol = &nlist[indirectSyms[sect->reserved1+i]];
3902 char *nm = image + symLC->stroff + symbol->n_un.n_strx;
3905 if((symbol->n_type & N_TYPE) == N_UNDF
3906 && (symbol->n_type & N_EXT) && (symbol->n_value != 0))
3907 addr = (void*) (symbol->n_value);
3908 else if((addr = lookupLocalSymbol(oc,nm)) != NULL)
3911 addr = lookupSymbol(nm);
3914 errorBelch("\n%s: unknown symbol `%s'", oc->fileName, nm);
3922 checkProddableBlock(oc,image + sect->offset + i*itemSize);
3923 *(image + sect->offset + i*itemSize) = 0xe9; // jmp
3924 *(unsigned*)(image + sect->offset + i*itemSize + 1)
3925 = (char*)addr - (image + sect->offset + i*itemSize + 5);
3930 checkProddableBlock(oc,((void**)(image + sect->offset)) + i);
3931 ((void**)(image + sect->offset))[i] = addr;
3938 static unsigned long relocateAddress(
3941 struct section* sections,
3942 unsigned long address)
3945 for(i = 0; i < nSections; i++)
3947 if(sections[i].addr <= address
3948 && address < sections[i].addr + sections[i].size)
3950 return (unsigned long)oc->image
3951 + sections[i].offset + address - sections[i].addr;
3954 barf("Invalid Mach-O file:"
3955 "Address out of bounds while relocating object file");
3959 static int relocateSection(
3962 struct symtab_command *symLC, struct nlist *nlist,
3963 int nSections, struct section* sections, struct section *sect)
3965 struct relocation_info *relocs;
3968 if(!strcmp(sect->sectname,"__la_symbol_ptr"))
3970 else if(!strcmp(sect->sectname,"__nl_symbol_ptr"))
3972 else if(!strcmp(sect->sectname,"__la_sym_ptr2"))
3974 else if(!strcmp(sect->sectname,"__la_sym_ptr3"))
3978 relocs = (struct relocation_info*) (image + sect->reloff);
3982 #ifdef x86_64_HOST_ARCH
3983 struct relocation_info *reloc = &relocs[i];
3985 char *thingPtr = image + sect->offset + reloc->r_address;
3989 int type = reloc->r_type;
3991 checkProddableBlock(oc,thingPtr);
3992 switch(reloc->r_length)
3995 thing = *(uint8_t*)thingPtr;
3996 baseValue = (uint64_t)thingPtr + 1;
3999 thing = *(uint16_t*)thingPtr;
4000 baseValue = (uint64_t)thingPtr + 2;
4003 thing = *(uint32_t*)thingPtr;
4004 baseValue = (uint64_t)thingPtr + 4;
4007 thing = *(uint64_t*)thingPtr;
4008 baseValue = (uint64_t)thingPtr + 8;
4011 barf("Unknown size.");
4014 if(type == X86_64_RELOC_GOT
4015 || type == X86_64_RELOC_GOT_LOAD)
4017 ASSERT(reloc->r_extern);
4018 value = (uint64_t) &makeSymbolExtra(oc, reloc->r_symbolnum, value)->addr;
4020 type = X86_64_RELOC_SIGNED;
4022 else if(reloc->r_extern)
4024 struct nlist *symbol = &nlist[reloc->r_symbolnum];
4025 char *nm = image + symLC->stroff + symbol->n_un.n_strx;
4026 if(symbol->n_value == 0)
4027 value = (uint64_t) lookupSymbol(nm);
4029 value = relocateAddress(oc, nSections, sections,
4034 value = sections[reloc->r_symbolnum-1].offset
4035 - sections[reloc->r_symbolnum-1].addr
4039 if(type == X86_64_RELOC_BRANCH)
4041 if((int32_t)(value - baseValue) != (int64_t)(value - baseValue))
4043 ASSERT(reloc->r_extern);
4044 value = (uint64_t) &makeSymbolExtra(oc, reloc->r_symbolnum, value)
4047 ASSERT((int32_t)(value - baseValue) == (int64_t)(value - baseValue));
4048 type = X86_64_RELOC_SIGNED;
4053 case X86_64_RELOC_UNSIGNED:
4054 ASSERT(!reloc->r_pcrel);
4057 case X86_64_RELOC_SIGNED:
4058 ASSERT(reloc->r_pcrel);
4059 thing += value - baseValue;
4061 case X86_64_RELOC_SUBTRACTOR:
4062 ASSERT(!reloc->r_pcrel);
4066 barf("unkown relocation");
4069 switch(reloc->r_length)
4072 *(uint8_t*)thingPtr = thing;
4075 *(uint16_t*)thingPtr = thing;
4078 *(uint32_t*)thingPtr = thing;
4081 *(uint64_t*)thingPtr = thing;
4085 if(relocs[i].r_address & R_SCATTERED)
4087 struct scattered_relocation_info *scat =
4088 (struct scattered_relocation_info*) &relocs[i];
4092 if(scat->r_length == 2)
4094 unsigned long word = 0;
4095 unsigned long* wordPtr = (unsigned long*) (image + sect->offset + scat->r_address);
4096 checkProddableBlock(oc,wordPtr);
4098 // Note on relocation types:
4099 // i386 uses the GENERIC_RELOC_* types,
4100 // while ppc uses special PPC_RELOC_* types.
4101 // *_RELOC_VANILLA and *_RELOC_PAIR have the same value
4102 // in both cases, all others are different.
4103 // Therefore, we use GENERIC_RELOC_VANILLA
4104 // and GENERIC_RELOC_PAIR instead of the PPC variants,
4105 // and use #ifdefs for the other types.
4107 // Step 1: Figure out what the relocated value should be
4108 if(scat->r_type == GENERIC_RELOC_VANILLA)
4110 word = *wordPtr + (unsigned long) relocateAddress(
4117 #ifdef powerpc_HOST_ARCH
4118 else if(scat->r_type == PPC_RELOC_SECTDIFF
4119 || scat->r_type == PPC_RELOC_LO16_SECTDIFF
4120 || scat->r_type == PPC_RELOC_HI16_SECTDIFF
4121 || scat->r_type == PPC_RELOC_HA16_SECTDIFF)
4123 else if(scat->r_type == GENERIC_RELOC_SECTDIFF)
4126 struct scattered_relocation_info *pair =
4127 (struct scattered_relocation_info*) &relocs[i+1];
4129 if(!pair->r_scattered || pair->r_type != GENERIC_RELOC_PAIR)
4130 barf("Invalid Mach-O file: "
4131 "RELOC_*_SECTDIFF not followed by RELOC_PAIR");
4133 word = (unsigned long)
4134 (relocateAddress(oc, nSections, sections, scat->r_value)
4135 - relocateAddress(oc, nSections, sections, pair->r_value));
4138 #ifdef powerpc_HOST_ARCH
4139 else if(scat->r_type == PPC_RELOC_HI16
4140 || scat->r_type == PPC_RELOC_LO16
4141 || scat->r_type == PPC_RELOC_HA16
4142 || scat->r_type == PPC_RELOC_LO14)
4143 { // these are generated by label+offset things
4144 struct relocation_info *pair = &relocs[i+1];
4145 if((pair->r_address & R_SCATTERED) || pair->r_type != PPC_RELOC_PAIR)
4146 barf("Invalid Mach-O file: "
4147 "PPC_RELOC_* not followed by PPC_RELOC_PAIR");
4149 if(scat->r_type == PPC_RELOC_LO16)
4151 word = ((unsigned short*) wordPtr)[1];
4152 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4154 else if(scat->r_type == PPC_RELOC_LO14)
4156 barf("Unsupported Relocation: PPC_RELOC_LO14");
4157 word = ((unsigned short*) wordPtr)[1] & 0xFFFC;
4158 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4160 else if(scat->r_type == PPC_RELOC_HI16)
4162 word = ((unsigned short*) wordPtr)[1] << 16;
4163 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
4165 else if(scat->r_type == PPC_RELOC_HA16)
4167 word = ((unsigned short*) wordPtr)[1] << 16;
4168 word += ((short)relocs[i+1].r_address & (short)0xFFFF);
4172 word += (unsigned long) relocateAddress(oc, nSections, sections, scat->r_value)
4179 continue; // ignore the others
4181 #ifdef powerpc_HOST_ARCH
4182 if(scat->r_type == GENERIC_RELOC_VANILLA
4183 || scat->r_type == PPC_RELOC_SECTDIFF)
4185 if(scat->r_type == GENERIC_RELOC_VANILLA
4186 || scat->r_type == GENERIC_RELOC_SECTDIFF)
4191 #ifdef powerpc_HOST_ARCH
4192 else if(scat->r_type == PPC_RELOC_LO16_SECTDIFF || scat->r_type == PPC_RELOC_LO16)
4194 ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
4196 else if(scat->r_type == PPC_RELOC_HI16_SECTDIFF || scat->r_type == PPC_RELOC_HI16)
4198 ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
4200 else if(scat->r_type == PPC_RELOC_HA16_SECTDIFF || scat->r_type == PPC_RELOC_HA16)
4202 ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
4203 + ((word & (1<<15)) ? 1 : 0);
4209 continue; // FIXME: I hope it's OK to ignore all the others.
4213 struct relocation_info *reloc = &relocs[i];
4214 if(reloc->r_pcrel && !reloc->r_extern)
4217 if(reloc->r_length == 2)
4219 unsigned long word = 0;
4220 #ifdef powerpc_HOST_ARCH
4221 unsigned long jumpIsland = 0;
4222 long offsetToJumpIsland = 0xBADBAD42; // initialise to bad value
4223 // to avoid warning and to catch
4227 unsigned long* wordPtr = (unsigned long*) (image + sect->offset + reloc->r_address);
4228 checkProddableBlock(oc,wordPtr);
4230 if(reloc->r_type == GENERIC_RELOC_VANILLA)
4234 #ifdef powerpc_HOST_ARCH
4235 else if(reloc->r_type == PPC_RELOC_LO16)
4237 word = ((unsigned short*) wordPtr)[1];
4238 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4240 else if(reloc->r_type == PPC_RELOC_HI16)
4242 word = ((unsigned short*) wordPtr)[1] << 16;
4243 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
4245 else if(reloc->r_type == PPC_RELOC_HA16)
4247 word = ((unsigned short*) wordPtr)[1] << 16;
4248 word += ((short)relocs[i+1].r_address & (short)0xFFFF);
4250 else if(reloc->r_type == PPC_RELOC_BR24)
4253 word = (word & 0x03FFFFFC) | ((word & 0x02000000) ? 0xFC000000 : 0);
4257 if(!reloc->r_extern)
4260 sections[reloc->r_symbolnum-1].offset
4261 - sections[reloc->r_symbolnum-1].addr
4268 struct nlist *symbol = &nlist[reloc->r_symbolnum];
4269 char *nm = image + symLC->stroff + symbol->n_un.n_strx;
4270 void *symbolAddress = lookupSymbol(nm);
4273 errorBelch("\nunknown symbol `%s'", nm);
4279 #ifdef powerpc_HOST_ARCH
4280 // In the .o file, this should be a relative jump to NULL
4281 // and we'll change it to a relative jump to the symbol
4282 ASSERT(word + reloc->r_address == 0);
4283 jumpIsland = (unsigned long)
4284 &makeSymbolExtra(oc,
4286 (unsigned long) symbolAddress)
4290 offsetToJumpIsland = word + jumpIsland
4291 - (((long)image) + sect->offset - sect->addr);
4294 word += (unsigned long) symbolAddress
4295 - (((long)image) + sect->offset - sect->addr);
4299 word += (unsigned long) symbolAddress;
4303 if(reloc->r_type == GENERIC_RELOC_VANILLA)
4308 #ifdef powerpc_HOST_ARCH
4309 else if(reloc->r_type == PPC_RELOC_LO16)
4311 ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
4314 else if(reloc->r_type == PPC_RELOC_HI16)
4316 ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
4319 else if(reloc->r_type == PPC_RELOC_HA16)
4321 ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
4322 + ((word & (1<<15)) ? 1 : 0);
4325 else if(reloc->r_type == PPC_RELOC_BR24)
4327 if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
4329 // The branch offset is too large.
4330 // Therefore, we try to use a jump island.
4333 barf("unconditional relative branch out of range: "
4334 "no jump island available");
4337 word = offsetToJumpIsland;
4338 if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
4339 barf("unconditional relative branch out of range: "
4340 "jump island out of range");
4342 *wordPtr = (*wordPtr & 0xFC000003) | (word & 0x03FFFFFC);
4347 barf("\nunknown relocation %d",reloc->r_type);
4355 static int ocGetNames_MachO(ObjectCode* oc)
4357 char *image = (char*) oc->image;
4358 struct mach_header *header = (struct mach_header*) image;
4359 struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
4360 unsigned i,curSymbol = 0;
4361 struct segment_command *segLC = NULL;
4362 struct section *sections;
4363 struct symtab_command *symLC = NULL;
4364 struct nlist *nlist;
4365 unsigned long commonSize = 0;
4366 char *commonStorage = NULL;
4367 unsigned long commonCounter;
4369 for(i=0;i<header->ncmds;i++)
4371 if(lc->cmd == LC_SEGMENT || lc->cmd == LC_SEGMENT_64)
4372 segLC = (struct segment_command*) lc;
4373 else if(lc->cmd == LC_SYMTAB)
4374 symLC = (struct symtab_command*) lc;
4375 lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
4378 sections = (struct section*) (segLC+1);
4379 nlist = symLC ? (struct nlist*) (image + symLC->symoff)
4383 barf("ocGetNames_MachO: no segment load command");
4385 for(i=0;i<segLC->nsects;i++)
4387 if(sections[i].size == 0)
4390 if((sections[i].flags & SECTION_TYPE) == S_ZEROFILL)
4392 char * zeroFillArea = stgCallocBytes(1,sections[i].size,
4393 "ocGetNames_MachO(common symbols)");
4394 sections[i].offset = zeroFillArea - image;
4397 if(!strcmp(sections[i].sectname,"__text"))
4398 addSection(oc, SECTIONKIND_CODE_OR_RODATA,
4399 (void*) (image + sections[i].offset),
4400 (void*) (image + sections[i].offset + sections[i].size));
4401 else if(!strcmp(sections[i].sectname,"__const"))
4402 addSection(oc, SECTIONKIND_RWDATA,
4403 (void*) (image + sections[i].offset),
4404 (void*) (image + sections[i].offset + sections[i].size));
4405 else if(!strcmp(sections[i].sectname,"__data"))
4406 addSection(oc, SECTIONKIND_RWDATA,
4407 (void*) (image + sections[i].offset),
4408 (void*) (image + sections[i].offset + sections[i].size));
4409 else if(!strcmp(sections[i].sectname,"__bss")
4410 || !strcmp(sections[i].sectname,"__common"))
4411 addSection(oc, SECTIONKIND_RWDATA,
4412 (void*) (image + sections[i].offset),
4413 (void*) (image + sections[i].offset + sections[i].size));
4415 addProddableBlock(oc, (void*) (image + sections[i].offset),
4419 // count external symbols defined here
4423 for(i=0;i<symLC->nsyms;i++)
4425 if(nlist[i].n_type & N_STAB)
4427 else if(nlist[i].n_type & N_EXT)
4429 if((nlist[i].n_type & N_TYPE) == N_UNDF
4430 && (nlist[i].n_value != 0))
4432 commonSize += nlist[i].n_value;
4435 else if((nlist[i].n_type & N_TYPE) == N_SECT)
4440 oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
4441 "ocGetNames_MachO(oc->symbols)");
4445 for(i=0;i<symLC->nsyms;i++)
4447 if(nlist[i].n_type & N_STAB)
4449 else if((nlist[i].n_type & N_TYPE) == N_SECT)
4451 if(nlist[i].n_type & N_EXT)
4453 char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
4454 if((nlist[i].n_desc & N_WEAK_DEF) && lookupSymbol(nm))
4455 ; // weak definition, and we already have a definition
4458 ghciInsertStrHashTable(oc->fileName, symhash, nm,
4460 + sections[nlist[i].n_sect-1].offset
4461 - sections[nlist[i].n_sect-1].addr
4462 + nlist[i].n_value);
4463 oc->symbols[curSymbol++] = nm;
4470 commonStorage = stgCallocBytes(1,commonSize,"ocGetNames_MachO(common symbols)");
4471 commonCounter = (unsigned long)commonStorage;
4474 for(i=0;i<symLC->nsyms;i++)
4476 if((nlist[i].n_type & N_TYPE) == N_UNDF
4477 && (nlist[i].n_type & N_EXT) && (nlist[i].n_value != 0))
4479 char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
4480 unsigned long sz = nlist[i].n_value;
4482 nlist[i].n_value = commonCounter;
4484 ghciInsertStrHashTable(oc->fileName, symhash, nm,
4485 (void*)commonCounter);
4486 oc->symbols[curSymbol++] = nm;
4488 commonCounter += sz;
4495 static int ocResolve_MachO(ObjectCode* oc)
4497 char *image = (char*) oc->image;
4498 struct mach_header *header = (struct mach_header*) image;
4499 struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
4501 struct segment_command *segLC = NULL;
4502 struct section *sections;
4503 struct symtab_command *symLC = NULL;
4504 struct dysymtab_command *dsymLC = NULL;
4505 struct nlist *nlist;
4507 for(i=0;i<header->ncmds;i++)
4509 if(lc->cmd == LC_SEGMENT || lc->cmd == LC_SEGMENT_64)
4510 segLC = (struct segment_command*) lc;
4511 else if(lc->cmd == LC_SYMTAB)
4512 symLC = (struct symtab_command*) lc;
4513 else if(lc->cmd == LC_DYSYMTAB)
4514 dsymLC = (struct dysymtab_command*) lc;
4515 lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
4518 sections = (struct section*) (segLC+1);
4519 nlist = symLC ? (struct nlist*) (image + symLC->symoff)
4524 unsigned long *indirectSyms
4525 = (unsigned long*) (image + dsymLC->indirectsymoff);
4527 for(i=0;i<segLC->nsects;i++)
4529 if( !strcmp(sections[i].sectname,"__la_symbol_ptr")
4530 || !strcmp(sections[i].sectname,"__la_sym_ptr2")
4531 || !strcmp(sections[i].sectname,"__la_sym_ptr3"))
4533 if(!resolveImports(oc,image,symLC,§ions[i],indirectSyms,nlist))
4536 else if(!strcmp(sections[i].sectname,"__nl_symbol_ptr")
4537 || !strcmp(sections[i].sectname,"__pointers"))
4539 if(!resolveImports(oc,image,symLC,§ions[i],indirectSyms,nlist))
4542 else if(!strcmp(sections[i].sectname,"__jump_table"))
4544 if(!resolveImports(oc,image,symLC,§ions[i],indirectSyms,nlist))
4550 for(i=0;i<segLC->nsects;i++)
4552 if(!relocateSection(oc,image,symLC,nlist,segLC->nsects,sections,§ions[i]))
4556 /* Free the local symbol table; we won't need it again. */
4557 freeHashTable(oc->lochash, NULL);
4560 #if defined (powerpc_HOST_ARCH)
4561 ocFlushInstructionCache( oc );
4567 #ifdef powerpc_HOST_ARCH
4569 * The Mach-O object format uses leading underscores. But not everywhere.
4570 * There is a small number of runtime support functions defined in
4571 * libcc_dynamic.a whose name does not have a leading underscore.
4572 * As a consequence, we can't get their address from C code.
4573 * We have to use inline assembler just to take the address of a function.
4577 static void machoInitSymbolsWithoutUnderscore()
4579 extern void* symbolsWithoutUnderscore[];
4580 void **p = symbolsWithoutUnderscore;
4581 __asm__ volatile(".globl _symbolsWithoutUnderscore\n.data\n_symbolsWithoutUnderscore:");
4585 __asm__ volatile(".long " # x);
4587 RTS_MACHO_NOUNDERLINE_SYMBOLS
4589 __asm__ volatile(".text");
4593 ghciInsertStrHashTable("(GHCi built-in symbols)", symhash, #x, *p++);
4595 RTS_MACHO_NOUNDERLINE_SYMBOLS
4602 * Figure out by how much to shift the entire Mach-O file in memory
4603 * when loading so that its single segment ends up 16-byte-aligned
4605 static int machoGetMisalignment( FILE * f )
4607 struct mach_header header;
4610 fread(&header, sizeof(header), 1, f);
4613 #if x86_64_TARGET_ARCH || powerpc64_TARGET_ARCH
4614 if(header.magic != MH_MAGIC_64)
4617 if(header.magic != MH_MAGIC)
4621 misalignment = (header.sizeofcmds + sizeof(header))
4624 return misalignment ? (16 - misalignment) : 0;