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"
32 #ifdef HAVE_SYS_TYPES_H
33 #include <sys/types.h>
39 #ifdef HAVE_SYS_STAT_H
43 #if defined(HAVE_DLFCN_H)
47 #if defined(cygwin32_HOST_OS)
52 #ifdef HAVE_SYS_TIME_H
56 #include <sys/fcntl.h>
57 #include <sys/termios.h>
58 #include <sys/utime.h>
59 #include <sys/utsname.h>
63 #if defined(ia64_HOST_ARCH) || defined(linux_HOST_OS) || defined(freebsd_HOST_OS) || defined(netbsd_HOST_OS) || defined(openbsd_HOST_OS)
68 #if defined(linux_HOST_OS) || defined(freebsd_HOST_OS) || defined(netbsd_HOST_OS) || defined(openbsd_HOST_OS)
76 #if defined(linux_HOST_OS) || defined(solaris2_HOST_OS) || defined(freebsd_HOST_OS) || defined(netbsd_HOST_OS) || defined(openbsd_HOST_OS)
77 # define OBJFORMAT_ELF
78 #elif defined(cygwin32_HOST_OS) || defined (mingw32_HOST_OS)
79 # define OBJFORMAT_PEi386
82 #elif defined(darwin_HOST_OS)
83 # define OBJFORMAT_MACHO
84 # include <mach-o/loader.h>
85 # include <mach-o/nlist.h>
86 # include <mach-o/reloc.h>
87 #if !defined(HAVE_DLFCN_H)
88 # include <mach-o/dyld.h>
90 #if defined(powerpc_HOST_ARCH)
91 # include <mach-o/ppc/reloc.h>
93 #if defined(x86_64_HOST_ARCH)
94 # include <mach-o/x86_64/reloc.h>
98 /* Hash table mapping symbol names to Symbol */
99 static /*Str*/HashTable *symhash;
101 /* Hash table mapping symbol names to StgStablePtr */
102 static /*Str*/HashTable *stablehash;
104 /* List of currently loaded objects */
105 ObjectCode *objects = NULL; /* initially empty */
107 #if defined(OBJFORMAT_ELF)
108 static int ocVerifyImage_ELF ( ObjectCode* oc );
109 static int ocGetNames_ELF ( ObjectCode* oc );
110 static int ocResolve_ELF ( ObjectCode* oc );
111 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
112 static int ocAllocateSymbolExtras_ELF ( ObjectCode* oc );
114 #elif defined(OBJFORMAT_PEi386)
115 static int ocVerifyImage_PEi386 ( ObjectCode* oc );
116 static int ocGetNames_PEi386 ( ObjectCode* oc );
117 static int ocResolve_PEi386 ( ObjectCode* oc );
118 #elif defined(OBJFORMAT_MACHO)
119 static int ocVerifyImage_MachO ( ObjectCode* oc );
120 static int ocGetNames_MachO ( ObjectCode* oc );
121 static int ocResolve_MachO ( ObjectCode* oc );
123 static int machoGetMisalignment( FILE * );
124 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
125 static int ocAllocateSymbolExtras_MachO ( ObjectCode* oc );
127 #ifdef powerpc_HOST_ARCH
128 static void machoInitSymbolsWithoutUnderscore( void );
132 /* on x86_64 we have a problem with relocating symbol references in
133 * code that was compiled without -fPIC. By default, the small memory
134 * model is used, which assumes that symbol references can fit in a
135 * 32-bit slot. The system dynamic linker makes this work for
136 * references to shared libraries by either (a) allocating a jump
137 * table slot for code references, or (b) moving the symbol at load
138 * time (and copying its contents, if necessary) for data references.
140 * We unfortunately can't tell whether symbol references are to code
141 * or data. So for now we assume they are code (the vast majority
142 * are), and allocate jump-table slots. Unfortunately this will
143 * SILENTLY generate crashing code for data references. This hack is
144 * enabled by X86_64_ELF_NONPIC_HACK.
146 * One workaround is to use shared Haskell libraries. This is
147 * coming. Another workaround is to keep the static libraries but
148 * compile them with -fPIC, because that will generate PIC references
149 * to data which can be relocated. The PIC code is still too green to
150 * do this systematically, though.
153 * See thread http://www.haskell.org/pipermail/cvs-ghc/2007-September/038458.html
155 #define X86_64_ELF_NONPIC_HACK 1
157 /* -----------------------------------------------------------------------------
158 * Built-in symbols from the RTS
161 typedef struct _RtsSymbolVal {
168 #define Maybe_Stable_Names SymX(mkWeakzh_fast) \
169 SymX(makeStableNamezh_fast) \
170 SymX(finalizzeWeakzh_fast)
172 /* These are not available in GUM!!! -- HWL */
173 #define Maybe_Stable_Names
176 #if !defined (mingw32_HOST_OS)
177 #define RTS_POSIX_ONLY_SYMBOLS \
178 SymX(shutdownHaskellAndSignal) \
181 SymX(signal_handlers) \
182 SymX(stg_sig_install) \
186 #if defined (cygwin32_HOST_OS)
187 #define RTS_MINGW_ONLY_SYMBOLS /**/
188 /* Don't have the ability to read import libs / archives, so
189 * we have to stupidly list a lot of what libcygwin.a
192 #define RTS_CYGWIN_ONLY_SYMBOLS \
270 #elif !defined(mingw32_HOST_OS)
271 #define RTS_MINGW_ONLY_SYMBOLS /**/
272 #define RTS_CYGWIN_ONLY_SYMBOLS /**/
273 #else /* defined(mingw32_HOST_OS) */
274 #define RTS_POSIX_ONLY_SYMBOLS /**/
275 #define RTS_CYGWIN_ONLY_SYMBOLS /**/
277 /* Extra syms gen'ed by mingw-2's gcc-3.2: */
279 #define RTS_MINGW_EXTRA_SYMS \
280 Sym(_imp____mb_cur_max) \
283 #define RTS_MINGW_EXTRA_SYMS
286 #if HAVE_GETTIMEOFDAY
287 #define RTS_MINGW_GETTIMEOFDAY_SYM Sym(gettimeofday)
289 #define RTS_MINGW_GETTIMEOFDAY_SYM /**/
292 /* These are statically linked from the mingw libraries into the ghc
293 executable, so we have to employ this hack. */
294 #define RTS_MINGW_ONLY_SYMBOLS \
295 SymX(asyncReadzh_fast) \
296 SymX(asyncWritezh_fast) \
297 SymX(asyncDoProczh_fast) \
309 SymX(getservbyname) \
310 SymX(getservbyport) \
311 SymX(getprotobynumber) \
312 SymX(getprotobyname) \
313 SymX(gethostbyname) \
314 SymX(gethostbyaddr) \
361 SymX(rts_InstallConsoleEvent) \
362 SymX(rts_ConsoleHandlerDone) \
364 Sym(_imp___timezone) \
374 RTS_MINGW_EXTRA_SYMS \
375 RTS_MINGW_GETTIMEOFDAY_SYM \
379 #if defined(darwin_TARGET_OS) && HAVE_PRINTF_LDBLSTUB
380 #define RTS_DARWIN_ONLY_SYMBOLS \
381 Sym(asprintf$LDBLStub) \
385 Sym(fprintf$LDBLStub) \
386 Sym(fscanf$LDBLStub) \
387 Sym(fwprintf$LDBLStub) \
388 Sym(fwscanf$LDBLStub) \
389 Sym(printf$LDBLStub) \
390 Sym(scanf$LDBLStub) \
391 Sym(snprintf$LDBLStub) \
392 Sym(sprintf$LDBLStub) \
393 Sym(sscanf$LDBLStub) \
394 Sym(strtold$LDBLStub) \
395 Sym(swprintf$LDBLStub) \
396 Sym(swscanf$LDBLStub) \
397 Sym(syslog$LDBLStub) \
398 Sym(vasprintf$LDBLStub) \
400 Sym(verrc$LDBLStub) \
401 Sym(verrx$LDBLStub) \
402 Sym(vfprintf$LDBLStub) \
403 Sym(vfscanf$LDBLStub) \
404 Sym(vfwprintf$LDBLStub) \
405 Sym(vfwscanf$LDBLStub) \
406 Sym(vprintf$LDBLStub) \
407 Sym(vscanf$LDBLStub) \
408 Sym(vsnprintf$LDBLStub) \
409 Sym(vsprintf$LDBLStub) \
410 Sym(vsscanf$LDBLStub) \
411 Sym(vswprintf$LDBLStub) \
412 Sym(vswscanf$LDBLStub) \
413 Sym(vsyslog$LDBLStub) \
414 Sym(vwarn$LDBLStub) \
415 Sym(vwarnc$LDBLStub) \
416 Sym(vwarnx$LDBLStub) \
417 Sym(vwprintf$LDBLStub) \
418 Sym(vwscanf$LDBLStub) \
420 Sym(warnc$LDBLStub) \
421 Sym(warnx$LDBLStub) \
422 Sym(wcstold$LDBLStub) \
423 Sym(wprintf$LDBLStub) \
426 #define RTS_DARWIN_ONLY_SYMBOLS
430 # define MAIN_CAP_SYM SymX(MainCapability)
432 # define MAIN_CAP_SYM
435 #if !defined(mingw32_HOST_OS)
436 #define RTS_USER_SIGNALS_SYMBOLS \
437 SymX(setIOManagerPipe)
439 #define RTS_USER_SIGNALS_SYMBOLS \
440 SymX(sendIOManagerEvent) \
441 SymX(readIOManagerEvent) \
442 SymX(getIOManagerEvent) \
443 SymX(console_handler)
446 #define RTS_LIBFFI_SYMBOLS \
450 Sym(ffi_type_float) \
451 Sym(ffi_type_double) \
452 Sym(ffi_type_sint64) \
453 Sym(ffi_type_uint64) \
454 Sym(ffi_type_sint32) \
455 Sym(ffi_type_uint32) \
456 Sym(ffi_type_sint16) \
457 Sym(ffi_type_uint16) \
458 Sym(ffi_type_sint8) \
459 Sym(ffi_type_uint8) \
460 Sym(ffi_type_pointer)
462 #ifdef TABLES_NEXT_TO_CODE
463 #define RTS_RET_SYMBOLS /* nothing */
465 #define RTS_RET_SYMBOLS \
466 SymX(stg_enter_ret) \
467 SymX(stg_gc_fun_ret) \
474 SymX(stg_ap_pv_ret) \
475 SymX(stg_ap_pp_ret) \
476 SymX(stg_ap_ppv_ret) \
477 SymX(stg_ap_ppp_ret) \
478 SymX(stg_ap_pppv_ret) \
479 SymX(stg_ap_pppp_ret) \
480 SymX(stg_ap_ppppp_ret) \
481 SymX(stg_ap_pppppp_ret)
484 /* On Windows, we link libgmp.a statically into libHSrts.dll */
485 #ifdef mingw32_HOST_OS
488 SymX(__gmpz_cmp_si) \
489 SymX(__gmpz_cmp_ui) \
490 SymX(__gmpz_get_si) \
494 SymExtern(__gmpz_cmp) \
495 SymExtern(__gmpz_cmp_si) \
496 SymExtern(__gmpz_cmp_ui) \
497 SymExtern(__gmpz_get_si) \
498 SymExtern(__gmpz_get_ui)
501 #define RTS_SYMBOLS \
504 SymX(stg_enter_info) \
505 SymX(stg_gc_void_info) \
506 SymX(__stg_gc_enter_1) \
507 SymX(stg_gc_noregs) \
508 SymX(stg_gc_unpt_r1_info) \
509 SymX(stg_gc_unpt_r1) \
510 SymX(stg_gc_unbx_r1_info) \
511 SymX(stg_gc_unbx_r1) \
512 SymX(stg_gc_f1_info) \
514 SymX(stg_gc_d1_info) \
516 SymX(stg_gc_l1_info) \
519 SymX(stg_gc_fun_info) \
521 SymX(stg_gc_gen_info) \
522 SymX(stg_gc_gen_hp) \
524 SymX(stg_gen_yield) \
525 SymX(stg_yield_noregs) \
526 SymX(stg_yield_to_interpreter) \
527 SymX(stg_gen_block) \
528 SymX(stg_block_noregs) \
530 SymX(stg_block_takemvar) \
531 SymX(stg_block_putmvar) \
533 SymX(MallocFailHook) \
535 SymX(OutOfHeapHook) \
536 SymX(StackOverflowHook) \
537 SymX(__encodeDouble) \
538 SymX(__encodeFloat) \
541 SymX(__int_encodeDouble) \
542 SymX(__word_encodeDouble) \
543 SymX(__2Int_encodeDouble) \
544 SymX(__int_encodeFloat) \
545 SymX(__word_encodeFloat) \
546 SymX(andIntegerzh_fast) \
547 SymX(atomicallyzh_fast) \
551 SymX(asyncExceptionsBlockedzh_fast) \
552 SymX(blockAsyncExceptionszh_fast) \
554 SymX(catchRetryzh_fast) \
555 SymX(catchSTMzh_fast) \
557 SymX(closure_flags) \
559 SymX(cmpIntegerzh_fast) \
560 SymX(cmpIntegerIntzh_fast) \
561 SymX(complementIntegerzh_fast) \
562 SymX(createAdjustor) \
563 SymX(decodeDoublezh_fast) \
564 SymX(decodeFloatzh_fast) \
565 SymX(decodeDoublezu2Intzh_fast) \
566 SymX(decodeFloatzuIntzh_fast) \
569 SymX(deRefWeakzh_fast) \
570 SymX(deRefStablePtrzh_fast) \
571 SymX(dirty_MUT_VAR) \
572 SymX(divExactIntegerzh_fast) \
573 SymX(divModIntegerzh_fast) \
575 SymX(forkOnzh_fast) \
577 SymX(forkOS_createThread) \
578 SymX(freeHaskellFunctionPtr) \
579 SymX(freeStablePtr) \
580 SymX(getOrSetTypeableStore) \
581 SymX(gcdIntegerzh_fast) \
582 SymX(gcdIntegerIntzh_fast) \
583 SymX(gcdIntzh_fast) \
587 SymX(getFullProgArgv) \
593 SymX(hs_perform_gc) \
594 SymX(hs_free_stable_ptr) \
595 SymX(hs_free_fun_ptr) \
596 SymX(hs_hpc_rootModule) \
598 SymX(unpackClosurezh_fast) \
599 SymX(getApStackValzh_fast) \
600 SymX(int2Integerzh_fast) \
601 SymX(integer2Intzh_fast) \
602 SymX(integer2Wordzh_fast) \
603 SymX(isCurrentThreadBoundzh_fast) \
604 SymX(isDoubleDenormalized) \
605 SymX(isDoubleInfinite) \
607 SymX(isDoubleNegativeZero) \
608 SymX(isEmptyMVarzh_fast) \
609 SymX(isFloatDenormalized) \
610 SymX(isFloatInfinite) \
612 SymX(isFloatNegativeZero) \
613 SymX(killThreadzh_fast) \
615 SymX(insertStableSymbol) \
618 SymX(makeStablePtrzh_fast) \
619 SymX(minusIntegerzh_fast) \
620 SymX(mkApUpd0zh_fast) \
621 SymX(myThreadIdzh_fast) \
622 SymX(labelThreadzh_fast) \
623 SymX(newArrayzh_fast) \
624 SymX(newBCOzh_fast) \
625 SymX(newByteArrayzh_fast) \
626 SymX_redirect(newCAF, newDynCAF) \
627 SymX(newMVarzh_fast) \
628 SymX(newMutVarzh_fast) \
629 SymX(newTVarzh_fast) \
630 SymX(noDuplicatezh_fast) \
631 SymX(atomicModifyMutVarzh_fast) \
632 SymX(newPinnedByteArrayzh_fast) \
634 SymX(orIntegerzh_fast) \
636 SymX(performMajorGC) \
637 SymX(plusIntegerzh_fast) \
640 SymX(putMVarzh_fast) \
641 SymX(quotIntegerzh_fast) \
642 SymX(quotRemIntegerzh_fast) \
644 SymX(raiseIOzh_fast) \
645 SymX(readTVarzh_fast) \
646 SymX(remIntegerzh_fast) \
647 SymX(resetNonBlockingFd) \
652 SymX(rts_checkSchedStatus) \
655 SymX(rts_evalLazyIO) \
656 SymX(rts_evalStableIO) \
660 SymX(rts_getDouble) \
668 SymX(rts_getFunPtr) \
669 SymX(rts_getStablePtr) \
670 SymX(rts_getThreadId) \
673 SymX(rts_getWord16) \
674 SymX(rts_getWord32) \
675 SymX(rts_getWord64) \
688 SymX(rts_mkStablePtr) \
696 SymX(rtsSupportsBoundThreads) \
697 SymX(__hscore_get_saved_termios) \
698 SymX(__hscore_set_saved_termios) \
700 SymX(startupHaskell) \
701 SymX(shutdownHaskell) \
702 SymX(shutdownHaskellAndExit) \
703 SymX(stable_ptr_table) \
704 SymX(stackOverflow) \
705 SymX(stg_CAF_BLACKHOLE_info) \
706 SymX(awakenBlockedQueue) \
708 SymX(stg_CHARLIKE_closure) \
709 SymX(stg_MVAR_CLEAN_info) \
710 SymX(stg_MVAR_DIRTY_info) \
711 SymX(stg_IND_STATIC_info) \
712 SymX(stg_INTLIKE_closure) \
713 SymX(stg_MUT_ARR_PTRS_DIRTY_info) \
714 SymX(stg_MUT_ARR_PTRS_FROZEN_info) \
715 SymX(stg_MUT_ARR_PTRS_FROZEN0_info) \
716 SymX(stg_WEAK_info) \
717 SymX(stg_ap_v_info) \
718 SymX(stg_ap_f_info) \
719 SymX(stg_ap_d_info) \
720 SymX(stg_ap_l_info) \
721 SymX(stg_ap_n_info) \
722 SymX(stg_ap_p_info) \
723 SymX(stg_ap_pv_info) \
724 SymX(stg_ap_pp_info) \
725 SymX(stg_ap_ppv_info) \
726 SymX(stg_ap_ppp_info) \
727 SymX(stg_ap_pppv_info) \
728 SymX(stg_ap_pppp_info) \
729 SymX(stg_ap_ppppp_info) \
730 SymX(stg_ap_pppppp_info) \
731 SymX(stg_ap_0_fast) \
732 SymX(stg_ap_v_fast) \
733 SymX(stg_ap_f_fast) \
734 SymX(stg_ap_d_fast) \
735 SymX(stg_ap_l_fast) \
736 SymX(stg_ap_n_fast) \
737 SymX(stg_ap_p_fast) \
738 SymX(stg_ap_pv_fast) \
739 SymX(stg_ap_pp_fast) \
740 SymX(stg_ap_ppv_fast) \
741 SymX(stg_ap_ppp_fast) \
742 SymX(stg_ap_pppv_fast) \
743 SymX(stg_ap_pppp_fast) \
744 SymX(stg_ap_ppppp_fast) \
745 SymX(stg_ap_pppppp_fast) \
746 SymX(stg_ap_1_upd_info) \
747 SymX(stg_ap_2_upd_info) \
748 SymX(stg_ap_3_upd_info) \
749 SymX(stg_ap_4_upd_info) \
750 SymX(stg_ap_5_upd_info) \
751 SymX(stg_ap_6_upd_info) \
752 SymX(stg_ap_7_upd_info) \
754 SymX(stg_sel_0_upd_info) \
755 SymX(stg_sel_10_upd_info) \
756 SymX(stg_sel_11_upd_info) \
757 SymX(stg_sel_12_upd_info) \
758 SymX(stg_sel_13_upd_info) \
759 SymX(stg_sel_14_upd_info) \
760 SymX(stg_sel_15_upd_info) \
761 SymX(stg_sel_1_upd_info) \
762 SymX(stg_sel_2_upd_info) \
763 SymX(stg_sel_3_upd_info) \
764 SymX(stg_sel_4_upd_info) \
765 SymX(stg_sel_5_upd_info) \
766 SymX(stg_sel_6_upd_info) \
767 SymX(stg_sel_7_upd_info) \
768 SymX(stg_sel_8_upd_info) \
769 SymX(stg_sel_9_upd_info) \
770 SymX(stg_upd_frame_info) \
771 SymX(suspendThread) \
772 SymX(takeMVarzh_fast) \
773 SymX(threadStatuszh_fast) \
774 SymX(timesIntegerzh_fast) \
775 SymX(tryPutMVarzh_fast) \
776 SymX(tryTakeMVarzh_fast) \
777 SymX(unblockAsyncExceptionszh_fast) \
779 SymX(unsafeThawArrayzh_fast) \
780 SymX(waitReadzh_fast) \
781 SymX(waitWritezh_fast) \
782 SymX(word2Integerzh_fast) \
783 SymX(writeTVarzh_fast) \
784 SymX(xorIntegerzh_fast) \
786 Sym(stg_interp_constr_entry) \
789 SymX(getAllocations) \
792 Sym(rts_breakpoint_io_action) \
793 Sym(rts_stop_next_breakpoint) \
794 Sym(rts_stop_on_exception) \
796 SymX(n_capabilities) \
797 RTS_USER_SIGNALS_SYMBOLS
799 #ifdef SUPPORT_LONG_LONGS
800 #define RTS_LONG_LONG_SYMS \
801 SymX(int64ToIntegerzh_fast) \
802 SymX(word64ToIntegerzh_fast)
804 #define RTS_LONG_LONG_SYMS /* nothing */
807 // 64-bit support functions in libgcc.a
808 #if defined(__GNUC__) && SIZEOF_VOID_P <= 4
809 #define RTS_LIBGCC_SYMBOLS \
819 #elif defined(ia64_HOST_ARCH)
820 #define RTS_LIBGCC_SYMBOLS \
828 #define RTS_LIBGCC_SYMBOLS
831 #if defined(darwin_HOST_OS) && defined(powerpc_HOST_ARCH)
832 // Symbols that don't have a leading underscore
833 // on Mac OS X. They have to receive special treatment,
834 // see machoInitSymbolsWithoutUnderscore()
835 #define RTS_MACHO_NOUNDERLINE_SYMBOLS \
840 /* entirely bogus claims about types of these symbols */
841 #define Sym(vvv) extern void vvv(void);
842 #if defined(__PIC__) && defined(mingw32_TARGET_OS)
843 #define SymExtern(vvv) extern void _imp__ ## vvv (void);
845 #define SymExtern(vvv) SymX(vvv)
847 #define SymX(vvv) /**/
848 #define SymX_redirect(vvv,xxx) /**/
852 RTS_POSIX_ONLY_SYMBOLS
853 RTS_MINGW_ONLY_SYMBOLS
854 RTS_CYGWIN_ONLY_SYMBOLS
855 RTS_DARWIN_ONLY_SYMBOLS
863 #ifdef LEADING_UNDERSCORE
864 #define MAYBE_LEADING_UNDERSCORE_STR(s) ("_" s)
866 #define MAYBE_LEADING_UNDERSCORE_STR(s) (s)
869 #define Sym(vvv) { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
871 #define SymX(vvv) Sym(vvv)
872 #define SymExtern(vvv) { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
873 (void*)DLL_IMPORT_DATA_REF(vvv) },
875 // SymX_redirect allows us to redirect references to one symbol to
876 // another symbol. See newCAF/newDynCAF for an example.
877 #define SymX_redirect(vvv,xxx) \
878 { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
881 static RtsSymbolVal rtsSyms[] = {
885 RTS_POSIX_ONLY_SYMBOLS
886 RTS_MINGW_ONLY_SYMBOLS
887 RTS_CYGWIN_ONLY_SYMBOLS
888 RTS_DARWIN_ONLY_SYMBOLS
891 #if defined(darwin_HOST_OS) && defined(i386_HOST_ARCH)
892 // dyld stub code contains references to this,
893 // but it should never be called because we treat
894 // lazy pointers as nonlazy.
895 { "dyld_stub_binding_helper", (void*)0xDEADBEEF },
897 { 0, 0 } /* sentinel */
902 /* -----------------------------------------------------------------------------
903 * Insert symbols into hash tables, checking for duplicates.
906 static void ghciInsertStrHashTable ( char* obj_name,
912 if (lookupHashTable(table, (StgWord)key) == NULL)
914 insertStrHashTable(table, (StgWord)key, data);
919 "GHCi runtime linker: fatal error: I found a duplicate definition for symbol\n"
921 "whilst processing object file\n"
923 "This could be caused by:\n"
924 " * Loading two different object files which export the same symbol\n"
925 " * Specifying the same object file twice on the GHCi command line\n"
926 " * An incorrect `package.conf' entry, causing some object to be\n"
928 "GHCi cannot safely continue in this situation. Exiting now. Sorry.\n"
935 /* -----------------------------------------------------------------------------
936 * initialize the object linker
940 static int linker_init_done = 0 ;
942 #if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
943 static void *dl_prog_handle;
951 /* Make initLinker idempotent, so we can call it
952 before evey relevant operation; that means we
953 don't need to initialise the linker separately */
954 if (linker_init_done == 1) { return; } else {
955 linker_init_done = 1;
958 stablehash = allocStrHashTable();
959 symhash = allocStrHashTable();
961 /* populate the symbol table with stuff from the RTS */
962 for (sym = rtsSyms; sym->lbl != NULL; sym++) {
963 ghciInsertStrHashTable("(GHCi built-in symbols)",
964 symhash, sym->lbl, sym->addr);
966 # if defined(OBJFORMAT_MACHO) && defined(powerpc_HOST_ARCH)
967 machoInitSymbolsWithoutUnderscore();
970 # if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
971 # if defined(RTLD_DEFAULT)
972 dl_prog_handle = RTLD_DEFAULT;
974 dl_prog_handle = dlopen(NULL, RTLD_LAZY);
975 # endif /* RTLD_DEFAULT */
979 /* -----------------------------------------------------------------------------
980 * Loading DLL or .so dynamic libraries
981 * -----------------------------------------------------------------------------
983 * Add a DLL from which symbols may be found. In the ELF case, just
984 * do RTLD_GLOBAL-style add, so no further messing around needs to
985 * happen in order that symbols in the loaded .so are findable --
986 * lookupSymbol() will subsequently see them by dlsym on the program's
987 * dl-handle. Returns NULL if success, otherwise ptr to an err msg.
989 * In the PEi386 case, open the DLLs and put handles to them in a
990 * linked list. When looking for a symbol, try all handles in the
991 * list. This means that we need to load even DLLs that are guaranteed
992 * to be in the ghc.exe image already, just so we can get a handle
993 * to give to loadSymbol, so that we can find the symbols. For such
994 * libraries, the LoadLibrary call should be a no-op except for returning
999 #if defined(OBJFORMAT_PEi386)
1000 /* A record for storing handles into DLLs. */
1005 struct _OpenedDLL* next;
1010 /* A list thereof. */
1011 static OpenedDLL* opened_dlls = NULL;
1015 addDLL( char *dll_name )
1017 # if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
1018 /* ------------------- ELF DLL loader ------------------- */
1024 // omitted: RTLD_NOW
1025 // see http://www.haskell.org/pipermail/cvs-ghc/2007-September/038570.html
1026 hdl= dlopen(dll_name, RTLD_LAZY | RTLD_GLOBAL);
1029 /* dlopen failed; return a ptr to the error msg. */
1031 if (errmsg == NULL) errmsg = "addDLL: unknown error";
1038 # elif defined(OBJFORMAT_PEi386)
1039 /* ------------------- Win32 DLL loader ------------------- */
1047 /* debugBelch("\naddDLL; dll_name = `%s'\n", dll_name); */
1049 /* See if we've already got it, and ignore if so. */
1050 for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
1051 if (0 == strcmp(o_dll->name, dll_name))
1055 /* The file name has no suffix (yet) so that we can try
1056 both foo.dll and foo.drv
1058 The documentation for LoadLibrary says:
1059 If no file name extension is specified in the lpFileName
1060 parameter, the default library extension .dll is
1061 appended. However, the file name string can include a trailing
1062 point character (.) to indicate that the module name has no
1065 buf = stgMallocBytes(strlen(dll_name) + 10, "addDLL");
1066 sprintf(buf, "%s.DLL", dll_name);
1067 instance = LoadLibrary(buf);
1068 if (instance == NULL) {
1069 sprintf(buf, "%s.DRV", dll_name); // KAA: allow loading of drivers (like winspool.drv)
1070 instance = LoadLibrary(buf);
1071 if (instance == NULL) {
1074 /* LoadLibrary failed; return a ptr to the error msg. */
1075 return "addDLL: unknown error";
1080 /* Add this DLL to the list of DLLs in which to search for symbols. */
1081 o_dll = stgMallocBytes( sizeof(OpenedDLL), "addDLL" );
1082 o_dll->name = stgMallocBytes(1+strlen(dll_name), "addDLL");
1083 strcpy(o_dll->name, dll_name);
1084 o_dll->instance = instance;
1085 o_dll->next = opened_dlls;
1086 opened_dlls = o_dll;
1090 barf("addDLL: not implemented on this platform");
1094 /* -----------------------------------------------------------------------------
1095 * insert a stable symbol in the hash table
1099 insertStableSymbol(char* obj_name, char* key, StgPtr p)
1101 ghciInsertStrHashTable(obj_name, stablehash, key, getStablePtr(p));
1105 /* -----------------------------------------------------------------------------
1106 * insert a symbol in the hash table
1109 insertSymbol(char* obj_name, char* key, void* data)
1111 ghciInsertStrHashTable(obj_name, symhash, key, data);
1114 /* -----------------------------------------------------------------------------
1115 * lookup a symbol in the hash table
1118 lookupSymbol( char *lbl )
1122 ASSERT(symhash != NULL);
1123 val = lookupStrHashTable(symhash, lbl);
1126 # if defined(OBJFORMAT_ELF)
1127 return dlsym(dl_prog_handle, lbl);
1128 # elif defined(OBJFORMAT_MACHO)
1130 /* On OS X 10.3 and later, we use dlsym instead of the old legacy
1133 HACK: On OS X, global symbols are prefixed with an underscore.
1134 However, dlsym wants us to omit the leading underscore from the
1135 symbol name. For now, we simply strip it off here (and ONLY
1138 ASSERT(lbl[0] == '_');
1139 return dlsym(dl_prog_handle, lbl+1);
1141 if(NSIsSymbolNameDefined(lbl)) {
1142 NSSymbol symbol = NSLookupAndBindSymbol(lbl);
1143 return NSAddressOfSymbol(symbol);
1147 # endif /* HAVE_DLFCN_H */
1148 # elif defined(OBJFORMAT_PEi386)
1151 for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
1152 /* debugBelch("look in %s for %s\n", o_dll->name, lbl); */
1153 if (lbl[0] == '_') {
1154 /* HACK: if the name has an initial underscore, try stripping
1155 it off & look that up first. I've yet to verify whether there's
1156 a Rule that governs whether an initial '_' *should always* be
1157 stripped off when mapping from import lib name to the DLL name.
1159 sym = GetProcAddress(o_dll->instance, (lbl+1));
1161 /*debugBelch("found %s in %s\n", lbl+1,o_dll->name);*/
1165 sym = GetProcAddress(o_dll->instance, lbl);
1167 /*debugBelch("found %s in %s\n", lbl,o_dll->name);*/
1181 /* -----------------------------------------------------------------------------
1182 * Debugging aid: look in GHCi's object symbol tables for symbols
1183 * within DELTA bytes of the specified address, and show their names.
1186 void ghci_enquire ( char* addr );
1188 void ghci_enquire ( char* addr )
1193 const int DELTA = 64;
1198 for (oc = objects; oc; oc = oc->next) {
1199 for (i = 0; i < oc->n_symbols; i++) {
1200 sym = oc->symbols[i];
1201 if (sym == NULL) continue;
1204 a = lookupStrHashTable(symhash, sym);
1207 // debugBelch("ghci_enquire: can't find %s\n", sym);
1209 else if (addr-DELTA <= a && a <= addr+DELTA) {
1210 debugBelch("%p + %3d == `%s'\n", addr, (int)(a - addr), sym);
1217 #ifdef ia64_HOST_ARCH
1218 static unsigned int PLTSize(void);
1221 /* -----------------------------------------------------------------------------
1222 * Load an obj (populate the global symbol table, but don't resolve yet)
1224 * Returns: 1 if ok, 0 on error.
1227 loadObj( char *path )
1234 void *map_addr = NULL;
1240 /* debugBelch("loadObj %s\n", path ); */
1242 /* Check that we haven't already loaded this object.
1243 Ignore requests to load multiple times */
1247 for (o = objects; o; o = o->next) {
1248 if (0 == strcmp(o->fileName, path)) {
1250 break; /* don't need to search further */
1254 IF_DEBUG(linker, debugBelch(
1255 "GHCi runtime linker: warning: looks like you're trying to load the\n"
1256 "same object file twice:\n"
1258 "GHCi will ignore this, but be warned.\n"
1260 return 1; /* success */
1264 oc = stgMallocBytes(sizeof(ObjectCode), "loadObj(oc)");
1266 # if defined(OBJFORMAT_ELF)
1267 oc->formatName = "ELF";
1268 # elif defined(OBJFORMAT_PEi386)
1269 oc->formatName = "PEi386";
1270 # elif defined(OBJFORMAT_MACHO)
1271 oc->formatName = "Mach-O";
1274 barf("loadObj: not implemented on this platform");
1277 r = stat(path, &st);
1278 if (r == -1) { return 0; }
1280 /* sigh, strdup() isn't a POSIX function, so do it the long way */
1281 oc->fileName = stgMallocBytes( strlen(path)+1, "loadObj" );
1282 strcpy(oc->fileName, path);
1284 oc->fileSize = st.st_size;
1286 oc->sections = NULL;
1287 oc->proddables = NULL;
1289 /* chain it onto the list of objects */
1294 #define ROUND_UP(x,size) ((x + size - 1) & ~(size - 1))
1296 /* On many architectures malloc'd memory isn't executable, so we need to use mmap. */
1298 #if defined(openbsd_HOST_OS)
1299 fd = open(path, O_RDONLY, S_IRUSR);
1301 fd = open(path, O_RDONLY);
1304 barf("loadObj: can't open `%s'", path);
1306 pagesize = getpagesize();
1308 #ifdef ia64_HOST_ARCH
1309 /* The PLT needs to be right before the object */
1310 n = ROUND_UP(PLTSize(), pagesize);
1311 oc->plt = mmap(NULL, n, PROT_EXEC|PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
1312 if (oc->plt == MAP_FAILED)
1313 barf("loadObj: can't allocate PLT");
1316 map_addr = oc->plt + n;
1319 n = ROUND_UP(oc->fileSize, pagesize);
1321 /* Link objects into the lower 2Gb on x86_64. GHC assumes the
1322 * small memory model on this architecture (see gcc docs,
1325 * MAP_32BIT not available on OpenBSD/amd64
1327 #if defined(x86_64_HOST_ARCH) && defined(MAP_32BIT)
1328 #define EXTRA_MAP_FLAGS MAP_32BIT
1330 #define EXTRA_MAP_FLAGS 0
1333 /* MAP_ANONYMOUS is MAP_ANON on some systems, e.g. OpenBSD */
1334 #if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
1335 #define MAP_ANONYMOUS MAP_ANON
1338 oc->image = mmap(map_addr, n, PROT_EXEC|PROT_READ|PROT_WRITE,
1339 MAP_PRIVATE|EXTRA_MAP_FLAGS, fd, 0);
1340 if (oc->image == MAP_FAILED)
1341 barf("loadObj: can't map `%s'", path);
1345 #else /* !USE_MMAP */
1347 /* load the image into memory */
1348 f = fopen(path, "rb");
1350 barf("loadObj: can't read `%s'", path);
1352 # if defined(mingw32_HOST_OS)
1353 // TODO: We would like to use allocateExec here, but allocateExec
1354 // cannot currently allocate blocks large enough.
1355 oc->image = VirtualAlloc(NULL, oc->fileSize, MEM_RESERVE | MEM_COMMIT,
1356 PAGE_EXECUTE_READWRITE);
1357 # elif defined(darwin_HOST_OS)
1358 // In a Mach-O .o file, all sections can and will be misaligned
1359 // if the total size of the headers is not a multiple of the
1360 // desired alignment. This is fine for .o files that only serve
1361 // as input for the static linker, but it's not fine for us,
1362 // as SSE (used by gcc for floating point) and Altivec require
1363 // 16-byte alignment.
1364 // We calculate the correct alignment from the header before
1365 // reading the file, and then we misalign oc->image on purpose so
1366 // that the actual sections end up aligned again.
1367 oc->misalignment = machoGetMisalignment(f);
1368 oc->image = stgMallocBytes(oc->fileSize + oc->misalignment, "loadObj(image)");
1369 oc->image += oc->misalignment;
1371 oc->image = stgMallocBytes(oc->fileSize, "loadObj(image)");
1374 n = fread ( oc->image, 1, oc->fileSize, f );
1375 if (n != oc->fileSize)
1376 barf("loadObj: error whilst reading `%s'", path);
1379 #endif /* USE_MMAP */
1381 # if defined(OBJFORMAT_MACHO) && (defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH))
1382 r = ocAllocateSymbolExtras_MachO ( oc );
1383 if (!r) { return r; }
1384 # elif defined(OBJFORMAT_ELF) && (defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH))
1385 r = ocAllocateSymbolExtras_ELF ( oc );
1386 if (!r) { return r; }
1389 /* verify the in-memory image */
1390 # if defined(OBJFORMAT_ELF)
1391 r = ocVerifyImage_ELF ( oc );
1392 # elif defined(OBJFORMAT_PEi386)
1393 r = ocVerifyImage_PEi386 ( oc );
1394 # elif defined(OBJFORMAT_MACHO)
1395 r = ocVerifyImage_MachO ( oc );
1397 barf("loadObj: no verify method");
1399 if (!r) { return r; }
1401 /* build the symbol list for this image */
1402 # if defined(OBJFORMAT_ELF)
1403 r = ocGetNames_ELF ( oc );
1404 # elif defined(OBJFORMAT_PEi386)
1405 r = ocGetNames_PEi386 ( oc );
1406 # elif defined(OBJFORMAT_MACHO)
1407 r = ocGetNames_MachO ( oc );
1409 barf("loadObj: no getNames method");
1411 if (!r) { return r; }
1413 /* loaded, but not resolved yet */
1414 oc->status = OBJECT_LOADED;
1419 /* -----------------------------------------------------------------------------
1420 * resolve all the currently unlinked objects in memory
1422 * Returns: 1 if ok, 0 on error.
1432 for (oc = objects; oc; oc = oc->next) {
1433 if (oc->status != OBJECT_RESOLVED) {
1434 # if defined(OBJFORMAT_ELF)
1435 r = ocResolve_ELF ( oc );
1436 # elif defined(OBJFORMAT_PEi386)
1437 r = ocResolve_PEi386 ( oc );
1438 # elif defined(OBJFORMAT_MACHO)
1439 r = ocResolve_MachO ( oc );
1441 barf("resolveObjs: not implemented on this platform");
1443 if (!r) { return r; }
1444 oc->status = OBJECT_RESOLVED;
1450 /* -----------------------------------------------------------------------------
1451 * delete an object from the pool
1454 unloadObj( char *path )
1456 ObjectCode *oc, *prev;
1458 ASSERT(symhash != NULL);
1459 ASSERT(objects != NULL);
1464 for (oc = objects; oc; prev = oc, oc = oc->next) {
1465 if (!strcmp(oc->fileName,path)) {
1467 /* Remove all the mappings for the symbols within this
1472 for (i = 0; i < oc->n_symbols; i++) {
1473 if (oc->symbols[i] != NULL) {
1474 removeStrHashTable(symhash, oc->symbols[i], NULL);
1482 prev->next = oc->next;
1485 // We're going to leave this in place, in case there are
1486 // any pointers from the heap into it:
1487 // #ifdef mingw32_HOST_OS
1488 // VirtualFree(oc->image);
1490 // stgFree(oc->image);
1492 stgFree(oc->fileName);
1493 stgFree(oc->symbols);
1494 stgFree(oc->sections);
1500 errorBelch("unloadObj: can't find `%s' to unload", path);
1504 /* -----------------------------------------------------------------------------
1505 * Sanity checking. For each ObjectCode, maintain a list of address ranges
1506 * which may be prodded during relocation, and abort if we try and write
1507 * outside any of these.
1509 static void addProddableBlock ( ObjectCode* oc, void* start, int size )
1512 = stgMallocBytes(sizeof(ProddableBlock), "addProddableBlock");
1513 /* debugBelch("aPB %p %p %d\n", oc, start, size); */
1517 pb->next = oc->proddables;
1518 oc->proddables = pb;
1521 static void checkProddableBlock ( ObjectCode* oc, void* addr )
1524 for (pb = oc->proddables; pb != NULL; pb = pb->next) {
1525 char* s = (char*)(pb->start);
1526 char* e = s + pb->size - 1;
1527 char* a = (char*)addr;
1528 /* Assumes that the biggest fixup involves a 4-byte write. This
1529 probably needs to be changed to 8 (ie, +7) on 64-bit
1531 if (a >= s && (a+3) <= e) return;
1533 barf("checkProddableBlock: invalid fixup in runtime linker");
1536 /* -----------------------------------------------------------------------------
1537 * Section management.
1539 static void addSection ( ObjectCode* oc, SectionKind kind,
1540 void* start, void* end )
1542 Section* s = stgMallocBytes(sizeof(Section), "addSection");
1546 s->next = oc->sections;
1549 debugBelch("addSection: %p-%p (size %d), kind %d\n",
1550 start, ((char*)end)-1, end - start + 1, kind );
1555 /* --------------------------------------------------------------------------
1557 * This is about allocating a small chunk of memory for every symbol in the
1558 * object file. We make sure that the SymboLExtras are always "in range" of
1559 * limited-range PC-relative instructions on various platforms by allocating
1560 * them right next to the object code itself.
1563 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
1566 ocAllocateSymbolExtras
1568 Allocate additional space at the end of the object file image to make room
1569 for jump islands (powerpc, x86_64) and GOT entries (x86_64).
1571 PowerPC relative branch instructions have a 24 bit displacement field.
1572 As PPC code is always 4-byte-aligned, this yields a +-32MB range.
1573 If a particular imported symbol is outside this range, we have to redirect
1574 the jump to a short piece of new code that just loads the 32bit absolute
1575 address and jumps there.
1576 On x86_64, PC-relative jumps and PC-relative accesses to the GOT are limited
1579 This function just allocates space for one SymbolExtra for every
1580 undefined symbol in the object file. The code for the jump islands is
1581 filled in by makeSymbolExtra below.
1584 static int ocAllocateSymbolExtras( ObjectCode* oc, int count, int first )
1591 int misalignment = 0;
1592 #ifdef darwin_HOST_OS
1593 misalignment = oc->misalignment;
1599 // round up to the nearest 4
1600 aligned = (oc->fileSize + 3) & ~3;
1603 #ifndef linux_HOST_OS /* mremap is a linux extension */
1604 #error ocAllocateSymbolExtras doesnt want USE_MMAP to be defined
1607 pagesize = getpagesize();
1608 n = ROUND_UP( oc->fileSize, pagesize );
1609 m = ROUND_UP( aligned + sizeof (SymbolExtra) * count, pagesize );
1611 /* If we have a half-page-size file and map one page of it then
1612 * the part of the page after the size of the file remains accessible.
1613 * If, however, we map in 2 pages, the 2nd page is not accessible
1614 * and will give a "Bus Error" on access. To get around this, we check
1615 * if we need any extra pages for the jump islands and map them in
1616 * anonymously. We must check that we actually require extra pages
1617 * otherwise the attempt to mmap 0 pages of anonymous memory will
1623 /* The effect of this mremap() call is only the ensure that we have
1624 * a sufficient number of virtually contiguous pages. As returned from
1625 * mremap, the pages past the end of the file are not backed. We give
1626 * them a backing by using MAP_FIXED to map in anonymous pages.
1628 oc->image = mremap( oc->image, n, m, MREMAP_MAYMOVE );
1630 if( oc->image == MAP_FAILED )
1632 errorBelch( "Unable to mremap for Jump Islands\n" );
1636 if( mmap( oc->image + n, m - n, PROT_READ | PROT_WRITE | PROT_EXEC,
1637 MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, 0, 0 ) == MAP_FAILED )
1639 errorBelch( "Unable to mmap( MAP_FIXED ) for Jump Islands\n" );
1645 oc->image -= misalignment;
1646 oc->image = stgReallocBytes( oc->image,
1648 aligned + sizeof (SymbolExtra) * count,
1649 "ocAllocateSymbolExtras" );
1650 oc->image += misalignment;
1651 #endif /* USE_MMAP */
1653 oc->symbol_extras = (SymbolExtra *) (oc->image + aligned);
1654 memset( oc->symbol_extras, 0, sizeof (SymbolExtra) * count );
1657 oc->symbol_extras = NULL;
1659 oc->first_symbol_extra = first;
1660 oc->n_symbol_extras = count;
1665 static SymbolExtra* makeSymbolExtra( ObjectCode* oc,
1666 unsigned long symbolNumber,
1667 unsigned long target )
1671 ASSERT( symbolNumber >= oc->first_symbol_extra
1672 && symbolNumber - oc->first_symbol_extra < oc->n_symbol_extras);
1674 extra = &oc->symbol_extras[symbolNumber - oc->first_symbol_extra];
1676 #ifdef powerpc_HOST_ARCH
1677 // lis r12, hi16(target)
1678 extra->jumpIsland.lis_r12 = 0x3d80;
1679 extra->jumpIsland.hi_addr = target >> 16;
1681 // ori r12, r12, lo16(target)
1682 extra->jumpIsland.ori_r12_r12 = 0x618c;
1683 extra->jumpIsland.lo_addr = target & 0xffff;
1686 extra->jumpIsland.mtctr_r12 = 0x7d8903a6;
1689 extra->jumpIsland.bctr = 0x4e800420;
1691 #ifdef x86_64_HOST_ARCH
1693 static uint8_t jmp[] = { 0xFF, 0x25, 0xF2, 0xFF, 0xFF, 0xFF };
1694 extra->addr = target;
1695 memcpy(extra->jumpIsland, jmp, 6);
1703 /* --------------------------------------------------------------------------
1704 * PowerPC specifics (instruction cache flushing)
1705 * ------------------------------------------------------------------------*/
1707 #ifdef powerpc_TARGET_ARCH
1709 ocFlushInstructionCache
1711 Flush the data & instruction caches.
1712 Because the PPC has split data/instruction caches, we have to
1713 do that whenever we modify code at runtime.
1716 static void ocFlushInstructionCache( ObjectCode *oc )
1718 int n = (oc->fileSize + sizeof( SymbolExtra ) * oc->n_symbol_extras + 3) / 4;
1719 unsigned long *p = (unsigned long *) oc->image;
1723 __asm__ volatile ( "dcbf 0,%0\n\t"
1731 __asm__ volatile ( "sync\n\t"
1737 /* --------------------------------------------------------------------------
1738 * PEi386 specifics (Win32 targets)
1739 * ------------------------------------------------------------------------*/
1741 /* The information for this linker comes from
1742 Microsoft Portable Executable
1743 and Common Object File Format Specification
1744 revision 5.1 January 1998
1745 which SimonM says comes from the MS Developer Network CDs.
1747 It can be found there (on older CDs), but can also be found
1750 http://www.microsoft.com/hwdev/hardware/PECOFF.asp
1752 (this is Rev 6.0 from February 1999).
1754 Things move, so if that fails, try searching for it via
1756 http://www.google.com/search?q=PE+COFF+specification
1758 The ultimate reference for the PE format is the Winnt.h
1759 header file that comes with the Platform SDKs; as always,
1760 implementations will drift wrt their documentation.
1762 A good background article on the PE format is Matt Pietrek's
1763 March 1994 article in Microsoft System Journal (MSJ)
1764 (Vol.9, No. 3): "Peering Inside the PE: A Tour of the
1765 Win32 Portable Executable File Format." The info in there
1766 has recently been updated in a two part article in
1767 MSDN magazine, issues Feb and March 2002,
1768 "Inside Windows: An In-Depth Look into the Win32 Portable
1769 Executable File Format"
1771 John Levine's book "Linkers and Loaders" contains useful
1776 #if defined(OBJFORMAT_PEi386)
1780 typedef unsigned char UChar;
1781 typedef unsigned short UInt16;
1782 typedef unsigned int UInt32;
1789 UInt16 NumberOfSections;
1790 UInt32 TimeDateStamp;
1791 UInt32 PointerToSymbolTable;
1792 UInt32 NumberOfSymbols;
1793 UInt16 SizeOfOptionalHeader;
1794 UInt16 Characteristics;
1798 #define sizeof_COFF_header 20
1805 UInt32 VirtualAddress;
1806 UInt32 SizeOfRawData;
1807 UInt32 PointerToRawData;
1808 UInt32 PointerToRelocations;
1809 UInt32 PointerToLinenumbers;
1810 UInt16 NumberOfRelocations;
1811 UInt16 NumberOfLineNumbers;
1812 UInt32 Characteristics;
1816 #define sizeof_COFF_section 40
1823 UInt16 SectionNumber;
1826 UChar NumberOfAuxSymbols;
1830 #define sizeof_COFF_symbol 18
1835 UInt32 VirtualAddress;
1836 UInt32 SymbolTableIndex;
1841 #define sizeof_COFF_reloc 10
1844 /* From PE spec doc, section 3.3.2 */
1845 /* Note use of MYIMAGE_* since IMAGE_* are already defined in
1846 windows.h -- for the same purpose, but I want to know what I'm
1848 #define MYIMAGE_FILE_RELOCS_STRIPPED 0x0001
1849 #define MYIMAGE_FILE_EXECUTABLE_IMAGE 0x0002
1850 #define MYIMAGE_FILE_DLL 0x2000
1851 #define MYIMAGE_FILE_SYSTEM 0x1000
1852 #define MYIMAGE_FILE_BYTES_REVERSED_HI 0x8000
1853 #define MYIMAGE_FILE_BYTES_REVERSED_LO 0x0080
1854 #define MYIMAGE_FILE_32BIT_MACHINE 0x0100
1856 /* From PE spec doc, section 5.4.2 and 5.4.4 */
1857 #define MYIMAGE_SYM_CLASS_EXTERNAL 2
1858 #define MYIMAGE_SYM_CLASS_STATIC 3
1859 #define MYIMAGE_SYM_UNDEFINED 0
1861 /* From PE spec doc, section 4.1 */
1862 #define MYIMAGE_SCN_CNT_CODE 0x00000020
1863 #define MYIMAGE_SCN_CNT_INITIALIZED_DATA 0x00000040
1864 #define MYIMAGE_SCN_LNK_NRELOC_OVFL 0x01000000
1866 /* From PE spec doc, section 5.2.1 */
1867 #define MYIMAGE_REL_I386_DIR32 0x0006
1868 #define MYIMAGE_REL_I386_REL32 0x0014
1871 /* We use myindex to calculate array addresses, rather than
1872 simply doing the normal subscript thing. That's because
1873 some of the above structs have sizes which are not
1874 a whole number of words. GCC rounds their sizes up to a
1875 whole number of words, which means that the address calcs
1876 arising from using normal C indexing or pointer arithmetic
1877 are just plain wrong. Sigh.
1880 myindex ( int scale, void* base, int index )
1883 ((UChar*)base) + scale * index;
1888 printName ( UChar* name, UChar* strtab )
1890 if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1891 UInt32 strtab_offset = * (UInt32*)(name+4);
1892 debugBelch("%s", strtab + strtab_offset );
1895 for (i = 0; i < 8; i++) {
1896 if (name[i] == 0) break;
1897 debugBelch("%c", name[i] );
1904 copyName ( UChar* name, UChar* strtab, UChar* dst, int dstSize )
1906 if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1907 UInt32 strtab_offset = * (UInt32*)(name+4);
1908 strncpy ( dst, strtab+strtab_offset, dstSize );
1914 if (name[i] == 0) break;
1924 cstring_from_COFF_symbol_name ( UChar* name, UChar* strtab )
1927 /* If the string is longer than 8 bytes, look in the
1928 string table for it -- this will be correctly zero terminated.
1930 if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1931 UInt32 strtab_offset = * (UInt32*)(name+4);
1932 return ((UChar*)strtab) + strtab_offset;
1934 /* Otherwise, if shorter than 8 bytes, return the original,
1935 which by defn is correctly terminated.
1937 if (name[7]==0) return name;
1938 /* The annoying case: 8 bytes. Copy into a temporary
1939 (which is never freed ...)
1941 newstr = stgMallocBytes(9, "cstring_from_COFF_symbol_name");
1943 strncpy(newstr,name,8);
1949 /* Just compares the short names (first 8 chars) */
1950 static COFF_section *
1951 findPEi386SectionCalled ( ObjectCode* oc, char* name )
1955 = (COFF_header*)(oc->image);
1956 COFF_section* sectab
1958 ((UChar*)(oc->image))
1959 + sizeof_COFF_header + hdr->SizeOfOptionalHeader
1961 for (i = 0; i < hdr->NumberOfSections; i++) {
1964 COFF_section* section_i
1966 myindex ( sizeof_COFF_section, sectab, i );
1967 n1 = (UChar*) &(section_i->Name);
1969 if (n1[0]==n2[0] && n1[1]==n2[1] && n1[2]==n2[2] &&
1970 n1[3]==n2[3] && n1[4]==n2[4] && n1[5]==n2[5] &&
1971 n1[6]==n2[6] && n1[7]==n2[7])
1980 zapTrailingAtSign ( UChar* sym )
1982 # define my_isdigit(c) ((c) >= '0' && (c) <= '9')
1984 if (sym[0] == 0) return;
1986 while (sym[i] != 0) i++;
1989 while (j > 0 && my_isdigit(sym[j])) j--;
1990 if (j > 0 && sym[j] == '@' && j != i) sym[j] = 0;
1996 ocVerifyImage_PEi386 ( ObjectCode* oc )
2001 COFF_section* sectab;
2002 COFF_symbol* symtab;
2004 /* debugBelch("\nLOADING %s\n", oc->fileName); */
2005 hdr = (COFF_header*)(oc->image);
2006 sectab = (COFF_section*) (
2007 ((UChar*)(oc->image))
2008 + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2010 symtab = (COFF_symbol*) (
2011 ((UChar*)(oc->image))
2012 + hdr->PointerToSymbolTable
2014 strtab = ((UChar*)symtab)
2015 + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2017 if (hdr->Machine != 0x14c) {
2018 errorBelch("%s: Not x86 PEi386", oc->fileName);
2021 if (hdr->SizeOfOptionalHeader != 0) {
2022 errorBelch("%s: PEi386 with nonempty optional header", oc->fileName);
2025 if ( /* (hdr->Characteristics & MYIMAGE_FILE_RELOCS_STRIPPED) || */
2026 (hdr->Characteristics & MYIMAGE_FILE_EXECUTABLE_IMAGE) ||
2027 (hdr->Characteristics & MYIMAGE_FILE_DLL) ||
2028 (hdr->Characteristics & MYIMAGE_FILE_SYSTEM) ) {
2029 errorBelch("%s: Not a PEi386 object file", oc->fileName);
2032 if ( (hdr->Characteristics & MYIMAGE_FILE_BYTES_REVERSED_HI)
2033 /* || !(hdr->Characteristics & MYIMAGE_FILE_32BIT_MACHINE) */ ) {
2034 errorBelch("%s: Invalid PEi386 word size or endiannness: %d",
2036 (int)(hdr->Characteristics));
2039 /* If the string table size is way crazy, this might indicate that
2040 there are more than 64k relocations, despite claims to the
2041 contrary. Hence this test. */
2042 /* debugBelch("strtab size %d\n", * (UInt32*)strtab); */
2044 if ( (*(UInt32*)strtab) > 600000 ) {
2045 /* Note that 600k has no special significance other than being
2046 big enough to handle the almost-2MB-sized lumps that
2047 constitute HSwin32*.o. */
2048 debugBelch("PEi386 object has suspiciously large string table; > 64k relocs?");
2053 /* No further verification after this point; only debug printing. */
2055 IF_DEBUG(linker, i=1);
2056 if (i == 0) return 1;
2058 debugBelch( "sectab offset = %d\n", ((UChar*)sectab) - ((UChar*)hdr) );
2059 debugBelch( "symtab offset = %d\n", ((UChar*)symtab) - ((UChar*)hdr) );
2060 debugBelch( "strtab offset = %d\n", ((UChar*)strtab) - ((UChar*)hdr) );
2063 debugBelch( "Machine: 0x%x\n", (UInt32)(hdr->Machine) );
2064 debugBelch( "# sections: %d\n", (UInt32)(hdr->NumberOfSections) );
2065 debugBelch( "time/date: 0x%x\n", (UInt32)(hdr->TimeDateStamp) );
2066 debugBelch( "symtab offset: %d\n", (UInt32)(hdr->PointerToSymbolTable) );
2067 debugBelch( "# symbols: %d\n", (UInt32)(hdr->NumberOfSymbols) );
2068 debugBelch( "sz of opt hdr: %d\n", (UInt32)(hdr->SizeOfOptionalHeader) );
2069 debugBelch( "characteristics: 0x%x\n", (UInt32)(hdr->Characteristics) );
2071 /* Print the section table. */
2073 for (i = 0; i < hdr->NumberOfSections; i++) {
2075 COFF_section* sectab_i
2077 myindex ( sizeof_COFF_section, sectab, i );
2084 printName ( sectab_i->Name, strtab );
2094 sectab_i->VirtualSize,
2095 sectab_i->VirtualAddress,
2096 sectab_i->SizeOfRawData,
2097 sectab_i->PointerToRawData,
2098 sectab_i->NumberOfRelocations,
2099 sectab_i->PointerToRelocations,
2100 sectab_i->PointerToRawData
2102 reltab = (COFF_reloc*) (
2103 ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
2106 if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
2107 /* If the relocation field (a short) has overflowed, the
2108 * real count can be found in the first reloc entry.
2110 * See Section 4.1 (last para) of the PE spec (rev6.0).
2112 COFF_reloc* rel = (COFF_reloc*)
2113 myindex ( sizeof_COFF_reloc, reltab, 0 );
2114 noRelocs = rel->VirtualAddress;
2117 noRelocs = sectab_i->NumberOfRelocations;
2121 for (; j < noRelocs; j++) {
2123 COFF_reloc* rel = (COFF_reloc*)
2124 myindex ( sizeof_COFF_reloc, reltab, j );
2126 " type 0x%-4x vaddr 0x%-8x name `",
2128 rel->VirtualAddress );
2129 sym = (COFF_symbol*)
2130 myindex ( sizeof_COFF_symbol, symtab, rel->SymbolTableIndex );
2131 /* Hmm..mysterious looking offset - what's it for? SOF */
2132 printName ( sym->Name, strtab -10 );
2139 debugBelch("string table has size 0x%x\n", * (UInt32*)strtab );
2140 debugBelch("---START of string table---\n");
2141 for (i = 4; i < *(Int32*)strtab; i++) {
2143 debugBelch("\n"); else
2144 debugBelch("%c", strtab[i] );
2146 debugBelch("--- END of string table---\n");
2151 COFF_symbol* symtab_i;
2152 if (i >= (Int32)(hdr->NumberOfSymbols)) break;
2153 symtab_i = (COFF_symbol*)
2154 myindex ( sizeof_COFF_symbol, symtab, i );
2160 printName ( symtab_i->Name, strtab );
2169 (Int32)(symtab_i->SectionNumber),
2170 (UInt32)symtab_i->Type,
2171 (UInt32)symtab_i->StorageClass,
2172 (UInt32)symtab_i->NumberOfAuxSymbols
2174 i += symtab_i->NumberOfAuxSymbols;
2184 ocGetNames_PEi386 ( ObjectCode* oc )
2187 COFF_section* sectab;
2188 COFF_symbol* symtab;
2195 hdr = (COFF_header*)(oc->image);
2196 sectab = (COFF_section*) (
2197 ((UChar*)(oc->image))
2198 + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2200 symtab = (COFF_symbol*) (
2201 ((UChar*)(oc->image))
2202 + hdr->PointerToSymbolTable
2204 strtab = ((UChar*)(oc->image))
2205 + hdr->PointerToSymbolTable
2206 + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2208 /* Allocate space for any (local, anonymous) .bss sections. */
2210 for (i = 0; i < hdr->NumberOfSections; i++) {
2213 COFF_section* sectab_i
2215 myindex ( sizeof_COFF_section, sectab, i );
2216 if (0 != strcmp(sectab_i->Name, ".bss")) continue;
2217 /* sof 10/05: the PE spec text isn't too clear regarding what
2218 * the SizeOfRawData field is supposed to hold for object
2219 * file sections containing just uninitialized data -- for executables,
2220 * it is supposed to be zero; unclear what it's supposed to be
2221 * for object files. However, VirtualSize is guaranteed to be
2222 * zero for object files, which definitely suggests that SizeOfRawData
2223 * will be non-zero (where else would the size of this .bss section be
2224 * stored?) Looking at the COFF_section info for incoming object files,
2225 * this certainly appears to be the case.
2227 * => I suspect we've been incorrectly handling .bss sections in (relocatable)
2228 * object files up until now. This turned out to bite us with ghc-6.4.1's use
2229 * of gcc-3.4.x, which has started to emit initially-zeroed-out local 'static'
2230 * variable decls into to the .bss section. (The specific function in Q which
2231 * triggered this is libraries/base/cbits/dirUtils.c:__hscore_getFolderPath())
2233 if (sectab_i->VirtualSize == 0 && sectab_i->SizeOfRawData == 0) continue;
2234 /* This is a non-empty .bss section. Allocate zeroed space for
2235 it, and set its PointerToRawData field such that oc->image +
2236 PointerToRawData == addr_of_zeroed_space. */
2237 bss_sz = sectab_i->VirtualSize;
2238 if ( bss_sz < sectab_i->SizeOfRawData) { bss_sz = sectab_i->SizeOfRawData; }
2239 zspace = stgCallocBytes(1, bss_sz, "ocGetNames_PEi386(anonymous bss)");
2240 sectab_i->PointerToRawData = ((UChar*)zspace) - ((UChar*)(oc->image));
2241 addProddableBlock(oc, zspace, bss_sz);
2242 /* debugBelch("BSS anon section at 0x%x\n", zspace); */
2245 /* Copy section information into the ObjectCode. */
2247 for (i = 0; i < hdr->NumberOfSections; i++) {
2253 = SECTIONKIND_OTHER;
2254 COFF_section* sectab_i
2256 myindex ( sizeof_COFF_section, sectab, i );
2257 IF_DEBUG(linker, debugBelch("section name = %s\n", sectab_i->Name ));
2260 /* I'm sure this is the Right Way to do it. However, the
2261 alternative of testing the sectab_i->Name field seems to
2262 work ok with Cygwin.
2264 if (sectab_i->Characteristics & MYIMAGE_SCN_CNT_CODE ||
2265 sectab_i->Characteristics & MYIMAGE_SCN_CNT_INITIALIZED_DATA)
2266 kind = SECTIONKIND_CODE_OR_RODATA;
2269 if (0==strcmp(".text",sectab_i->Name) ||
2270 0==strcmp(".rdata",sectab_i->Name)||
2271 0==strcmp(".rodata",sectab_i->Name))
2272 kind = SECTIONKIND_CODE_OR_RODATA;
2273 if (0==strcmp(".data",sectab_i->Name) ||
2274 0==strcmp(".bss",sectab_i->Name))
2275 kind = SECTIONKIND_RWDATA;
2277 ASSERT(sectab_i->SizeOfRawData == 0 || sectab_i->VirtualSize == 0);
2278 sz = sectab_i->SizeOfRawData;
2279 if (sz < sectab_i->VirtualSize) sz = sectab_i->VirtualSize;
2281 start = ((UChar*)(oc->image)) + sectab_i->PointerToRawData;
2282 end = start + sz - 1;
2284 if (kind == SECTIONKIND_OTHER
2285 /* Ignore sections called which contain stabs debugging
2287 && 0 != strcmp(".stab", sectab_i->Name)
2288 && 0 != strcmp(".stabstr", sectab_i->Name)
2289 /* ignore constructor section for now */
2290 && 0 != strcmp(".ctors", sectab_i->Name)
2291 /* ignore section generated from .ident */
2292 && 0!= strcmp("/4", sectab_i->Name)
2293 /* ignore unknown section that appeared in gcc 3.4.5(?) */
2294 && 0!= strcmp(".reloc", sectab_i->Name)
2296 errorBelch("Unknown PEi386 section name `%s' (while processing: %s)", sectab_i->Name, oc->fileName);
2300 if (kind != SECTIONKIND_OTHER && end >= start) {
2301 addSection(oc, kind, start, end);
2302 addProddableBlock(oc, start, end - start + 1);
2306 /* Copy exported symbols into the ObjectCode. */
2308 oc->n_symbols = hdr->NumberOfSymbols;
2309 oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
2310 "ocGetNames_PEi386(oc->symbols)");
2311 /* Call me paranoid; I don't care. */
2312 for (i = 0; i < oc->n_symbols; i++)
2313 oc->symbols[i] = NULL;
2317 COFF_symbol* symtab_i;
2318 if (i >= (Int32)(hdr->NumberOfSymbols)) break;
2319 symtab_i = (COFF_symbol*)
2320 myindex ( sizeof_COFF_symbol, symtab, i );
2324 if (symtab_i->StorageClass == MYIMAGE_SYM_CLASS_EXTERNAL
2325 && symtab_i->SectionNumber != MYIMAGE_SYM_UNDEFINED) {
2326 /* This symbol is global and defined, viz, exported */
2327 /* for MYIMAGE_SYMCLASS_EXTERNAL
2328 && !MYIMAGE_SYM_UNDEFINED,
2329 the address of the symbol is:
2330 address of relevant section + offset in section
2332 COFF_section* sectabent
2333 = (COFF_section*) myindex ( sizeof_COFF_section,
2335 symtab_i->SectionNumber-1 );
2336 addr = ((UChar*)(oc->image))
2337 + (sectabent->PointerToRawData
2341 if (symtab_i->SectionNumber == MYIMAGE_SYM_UNDEFINED
2342 && symtab_i->Value > 0) {
2343 /* This symbol isn't in any section at all, ie, global bss.
2344 Allocate zeroed space for it. */
2345 addr = stgCallocBytes(1, symtab_i->Value,
2346 "ocGetNames_PEi386(non-anonymous bss)");
2347 addSection(oc, SECTIONKIND_RWDATA, addr,
2348 ((UChar*)addr) + symtab_i->Value - 1);
2349 addProddableBlock(oc, addr, symtab_i->Value);
2350 /* debugBelch("BSS section at 0x%x\n", addr); */
2353 if (addr != NULL ) {
2354 sname = cstring_from_COFF_symbol_name ( symtab_i->Name, strtab );
2355 /* debugBelch("addSymbol %p `%s \n", addr,sname); */
2356 IF_DEBUG(linker, debugBelch("addSymbol %p `%s'\n", addr,sname);)
2357 ASSERT(i >= 0 && i < oc->n_symbols);
2358 /* cstring_from_COFF_symbol_name always succeeds. */
2359 oc->symbols[i] = sname;
2360 ghciInsertStrHashTable(oc->fileName, symhash, sname, addr);
2364 "IGNORING symbol %d\n"
2368 printName ( symtab_i->Name, strtab );
2377 (Int32)(symtab_i->SectionNumber),
2378 (UInt32)symtab_i->Type,
2379 (UInt32)symtab_i->StorageClass,
2380 (UInt32)symtab_i->NumberOfAuxSymbols
2385 i += symtab_i->NumberOfAuxSymbols;
2394 ocResolve_PEi386 ( ObjectCode* oc )
2397 COFF_section* sectab;
2398 COFF_symbol* symtab;
2408 /* ToDo: should be variable-sized? But is at least safe in the
2409 sense of buffer-overrun-proof. */
2411 /* debugBelch("resolving for %s\n", oc->fileName); */
2413 hdr = (COFF_header*)(oc->image);
2414 sectab = (COFF_section*) (
2415 ((UChar*)(oc->image))
2416 + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2418 symtab = (COFF_symbol*) (
2419 ((UChar*)(oc->image))
2420 + hdr->PointerToSymbolTable
2422 strtab = ((UChar*)(oc->image))
2423 + hdr->PointerToSymbolTable
2424 + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2426 for (i = 0; i < hdr->NumberOfSections; i++) {
2427 COFF_section* sectab_i
2429 myindex ( sizeof_COFF_section, sectab, i );
2432 ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
2435 /* Ignore sections called which contain stabs debugging
2437 if (0 == strcmp(".stab", sectab_i->Name)
2438 || 0 == strcmp(".stabstr", sectab_i->Name)
2439 || 0 == strcmp(".ctors", sectab_i->Name))
2442 if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
2443 /* If the relocation field (a short) has overflowed, the
2444 * real count can be found in the first reloc entry.
2446 * See Section 4.1 (last para) of the PE spec (rev6.0).
2448 * Nov2003 update: the GNU linker still doesn't correctly
2449 * handle the generation of relocatable object files with
2450 * overflown relocations. Hence the output to warn of potential
2453 COFF_reloc* rel = (COFF_reloc*)
2454 myindex ( sizeof_COFF_reloc, reltab, 0 );
2455 noRelocs = rel->VirtualAddress;
2457 /* 10/05: we now assume (and check for) a GNU ld that is capable
2458 * of handling object files with (>2^16) of relocs.
2461 debugBelch("WARNING: Overflown relocation field (# relocs found: %u)\n",
2466 noRelocs = sectab_i->NumberOfRelocations;
2471 for (; j < noRelocs; j++) {
2473 COFF_reloc* reltab_j
2475 myindex ( sizeof_COFF_reloc, reltab, j );
2477 /* the location to patch */
2479 ((UChar*)(oc->image))
2480 + (sectab_i->PointerToRawData
2481 + reltab_j->VirtualAddress
2482 - sectab_i->VirtualAddress )
2484 /* the existing contents of pP */
2486 /* the symbol to connect to */
2487 sym = (COFF_symbol*)
2488 myindex ( sizeof_COFF_symbol,
2489 symtab, reltab_j->SymbolTableIndex );
2492 "reloc sec %2d num %3d: type 0x%-4x "
2493 "vaddr 0x%-8x name `",
2495 (UInt32)reltab_j->Type,
2496 reltab_j->VirtualAddress );
2497 printName ( sym->Name, strtab );
2498 debugBelch("'\n" ));
2500 if (sym->StorageClass == MYIMAGE_SYM_CLASS_STATIC) {
2501 COFF_section* section_sym
2502 = findPEi386SectionCalled ( oc, sym->Name );
2504 errorBelch("%s: can't find section `%s'", oc->fileName, sym->Name);
2507 S = ((UInt32)(oc->image))
2508 + (section_sym->PointerToRawData
2511 copyName ( sym->Name, strtab, symbol, 1000-1 );
2512 S = (UInt32) lookupSymbol( symbol );
2513 if ((void*)S != NULL) goto foundit;
2514 zapTrailingAtSign ( symbol );
2515 S = (UInt32) lookupSymbol( symbol );
2516 if ((void*)S != NULL) goto foundit;
2517 /* Newline first because the interactive linker has printed "linking..." */
2518 errorBelch("\n%s: unknown symbol `%s'", oc->fileName, symbol);
2522 checkProddableBlock(oc, pP);
2523 switch (reltab_j->Type) {
2524 case MYIMAGE_REL_I386_DIR32:
2527 case MYIMAGE_REL_I386_REL32:
2528 /* Tricky. We have to insert a displacement at
2529 pP which, when added to the PC for the _next_
2530 insn, gives the address of the target (S).
2531 Problem is to know the address of the next insn
2532 when we only know pP. We assume that this
2533 literal field is always the last in the insn,
2534 so that the address of the next insn is pP+4
2535 -- hence the constant 4.
2536 Also I don't know if A should be added, but so
2537 far it has always been zero.
2539 SOF 05/2005: 'A' (old contents of *pP) have been observed
2540 to contain values other than zero (the 'wx' object file
2541 that came with wxhaskell-0.9.4; dunno how it was compiled..).
2542 So, add displacement to old value instead of asserting
2543 A to be zero. Fixes wxhaskell-related crashes, and no other
2544 ill effects have been observed.
2546 Update: the reason why we're seeing these more elaborate
2547 relocations is due to a switch in how the NCG compiles SRTs
2548 and offsets to them from info tables. SRTs live in .(ro)data,
2549 while info tables live in .text, causing GAS to emit REL32/DISP32
2550 relocations with non-zero values. Adding the displacement is
2551 the right thing to do.
2553 *pP = S - ((UInt32)pP) - 4 + A;
2556 debugBelch("%s: unhandled PEi386 relocation type %d",
2557 oc->fileName, reltab_j->Type);
2564 IF_DEBUG(linker, debugBelch("completed %s", oc->fileName));
2568 #endif /* defined(OBJFORMAT_PEi386) */
2571 /* --------------------------------------------------------------------------
2573 * ------------------------------------------------------------------------*/
2575 #if defined(OBJFORMAT_ELF)
2580 #if defined(sparc_HOST_ARCH)
2581 # define ELF_TARGET_SPARC /* Used inside <elf.h> */
2582 #elif defined(i386_HOST_ARCH)
2583 # define ELF_TARGET_386 /* Used inside <elf.h> */
2584 #elif defined(x86_64_HOST_ARCH)
2585 # define ELF_TARGET_X64_64
2587 #elif defined (ia64_HOST_ARCH)
2588 # define ELF_TARGET_IA64 /* Used inside <elf.h> */
2590 # define ELF_FUNCTION_DESC /* calling convention uses function descriptors */
2591 # define ELF_NEED_GOT /* needs Global Offset Table */
2592 # define ELF_NEED_PLT /* needs Procedure Linkage Tables */
2595 #if !defined(openbsd_HOST_OS)
2598 /* openbsd elf has things in different places, with diff names */
2599 # include <elf_abi.h>
2600 # include <machine/reloc.h>
2601 # define R_386_32 RELOC_32
2602 # define R_386_PC32 RELOC_PC32
2605 /* If elf.h doesn't define it */
2606 # ifndef R_X86_64_PC64
2607 # define R_X86_64_PC64 24
2611 * Define a set of types which can be used for both ELF32 and ELF64
2615 #define ELFCLASS ELFCLASS64
2616 #define Elf_Addr Elf64_Addr
2617 #define Elf_Word Elf64_Word
2618 #define Elf_Sword Elf64_Sword
2619 #define Elf_Ehdr Elf64_Ehdr
2620 #define Elf_Phdr Elf64_Phdr
2621 #define Elf_Shdr Elf64_Shdr
2622 #define Elf_Sym Elf64_Sym
2623 #define Elf_Rel Elf64_Rel
2624 #define Elf_Rela Elf64_Rela
2625 #define ELF_ST_TYPE ELF64_ST_TYPE
2626 #define ELF_ST_BIND ELF64_ST_BIND
2627 #define ELF_R_TYPE ELF64_R_TYPE
2628 #define ELF_R_SYM ELF64_R_SYM
2630 #define ELFCLASS ELFCLASS32
2631 #define Elf_Addr Elf32_Addr
2632 #define Elf_Word Elf32_Word
2633 #define Elf_Sword Elf32_Sword
2634 #define Elf_Ehdr Elf32_Ehdr
2635 #define Elf_Phdr Elf32_Phdr
2636 #define Elf_Shdr Elf32_Shdr
2637 #define Elf_Sym Elf32_Sym
2638 #define Elf_Rel Elf32_Rel
2639 #define Elf_Rela Elf32_Rela
2641 #define ELF_ST_TYPE ELF32_ST_TYPE
2644 #define ELF_ST_BIND ELF32_ST_BIND
2647 #define ELF_R_TYPE ELF32_R_TYPE
2650 #define ELF_R_SYM ELF32_R_SYM
2656 * Functions to allocate entries in dynamic sections. Currently we simply
2657 * preallocate a large number, and we don't check if a entry for the given
2658 * target already exists (a linear search is too slow). Ideally these
2659 * entries would be associated with symbols.
2662 /* These sizes sufficient to load HSbase + HShaskell98 + a few modules */
2663 #define GOT_SIZE 0x20000
2664 #define FUNCTION_TABLE_SIZE 0x10000
2665 #define PLT_SIZE 0x08000
2668 static Elf_Addr got[GOT_SIZE];
2669 static unsigned int gotIndex;
2670 static Elf_Addr gp_val = (Elf_Addr)got;
2673 allocateGOTEntry(Elf_Addr target)
2677 if (gotIndex >= GOT_SIZE)
2678 barf("Global offset table overflow");
2680 entry = &got[gotIndex++];
2682 return (Elf_Addr)entry;
2686 #ifdef ELF_FUNCTION_DESC
2692 static FunctionDesc functionTable[FUNCTION_TABLE_SIZE];
2693 static unsigned int functionTableIndex;
2696 allocateFunctionDesc(Elf_Addr target)
2698 FunctionDesc *entry;
2700 if (functionTableIndex >= FUNCTION_TABLE_SIZE)
2701 barf("Function table overflow");
2703 entry = &functionTable[functionTableIndex++];
2705 entry->gp = (Elf_Addr)gp_val;
2706 return (Elf_Addr)entry;
2710 copyFunctionDesc(Elf_Addr target)
2712 FunctionDesc *olddesc = (FunctionDesc *)target;
2713 FunctionDesc *newdesc;
2715 newdesc = (FunctionDesc *)allocateFunctionDesc(olddesc->ip);
2716 newdesc->gp = olddesc->gp;
2717 return (Elf_Addr)newdesc;
2722 #ifdef ia64_HOST_ARCH
2723 static void ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value);
2724 static void ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc);
2726 static unsigned char plt_code[] =
2728 /* taken from binutils bfd/elfxx-ia64.c */
2729 0x0b, 0x78, 0x00, 0x02, 0x00, 0x24, /* [MMI] addl r15=0,r1;; */
2730 0x00, 0x41, 0x3c, 0x30, 0x28, 0xc0, /* ld8 r16=[r15],8 */
2731 0x01, 0x08, 0x00, 0x84, /* mov r14=r1;; */
2732 0x11, 0x08, 0x00, 0x1e, 0x18, 0x10, /* [MIB] ld8 r1=[r15] */
2733 0x60, 0x80, 0x04, 0x80, 0x03, 0x00, /* mov b6=r16 */
2734 0x60, 0x00, 0x80, 0x00 /* br.few b6;; */
2737 /* If we can't get to the function descriptor via gp, take a local copy of it */
2738 #define PLT_RELOC(code, target) { \
2739 Elf64_Sxword rel_value = target - gp_val; \
2740 if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff)) \
2741 ia64_reloc_gprel22((Elf_Addr)code, copyFunctionDesc(target)); \
2743 ia64_reloc_gprel22((Elf_Addr)code, target); \
2748 unsigned char code[sizeof(plt_code)];
2752 allocatePLTEntry(Elf_Addr target, ObjectCode *oc)
2754 PLTEntry *plt = (PLTEntry *)oc->plt;
2757 if (oc->pltIndex >= PLT_SIZE)
2758 barf("Procedure table overflow");
2760 entry = &plt[oc->pltIndex++];
2761 memcpy(entry->code, plt_code, sizeof(entry->code));
2762 PLT_RELOC(entry->code, target);
2763 return (Elf_Addr)entry;
2769 return (PLT_SIZE * sizeof(PLTEntry));
2775 * Generic ELF functions
2779 findElfSection ( void* objImage, Elf_Word sh_type )
2781 char* ehdrC = (char*)objImage;
2782 Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2783 Elf_Shdr* shdr = (Elf_Shdr*)(ehdrC + ehdr->e_shoff);
2784 char* sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
2788 for (i = 0; i < ehdr->e_shnum; i++) {
2789 if (shdr[i].sh_type == sh_type
2790 /* Ignore the section header's string table. */
2791 && i != ehdr->e_shstrndx
2792 /* Ignore string tables named .stabstr, as they contain
2794 && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
2796 ptr = ehdrC + shdr[i].sh_offset;
2803 #if defined(ia64_HOST_ARCH)
2805 findElfSegment ( void* objImage, Elf_Addr vaddr )
2807 char* ehdrC = (char*)objImage;
2808 Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2809 Elf_Phdr* phdr = (Elf_Phdr*)(ehdrC + ehdr->e_phoff);
2810 Elf_Addr segaddr = 0;
2813 for (i = 0; i < ehdr->e_phnum; i++) {
2814 segaddr = phdr[i].p_vaddr;
2815 if ((vaddr >= segaddr) && (vaddr < segaddr + phdr[i].p_memsz))
2823 ocVerifyImage_ELF ( ObjectCode* oc )
2827 int i, j, nent, nstrtab, nsymtabs;
2831 char* ehdrC = (char*)(oc->image);
2832 Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2834 if (ehdr->e_ident[EI_MAG0] != ELFMAG0 ||
2835 ehdr->e_ident[EI_MAG1] != ELFMAG1 ||
2836 ehdr->e_ident[EI_MAG2] != ELFMAG2 ||
2837 ehdr->e_ident[EI_MAG3] != ELFMAG3) {
2838 errorBelch("%s: not an ELF object", oc->fileName);
2842 if (ehdr->e_ident[EI_CLASS] != ELFCLASS) {
2843 errorBelch("%s: unsupported ELF format", oc->fileName);
2847 if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) {
2848 IF_DEBUG(linker,debugBelch( "Is little-endian\n" ));
2850 if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) {
2851 IF_DEBUG(linker,debugBelch( "Is big-endian\n" ));
2853 errorBelch("%s: unknown endiannness", oc->fileName);
2857 if (ehdr->e_type != ET_REL) {
2858 errorBelch("%s: not a relocatable object (.o) file", oc->fileName);
2861 IF_DEBUG(linker, debugBelch( "Is a relocatable object (.o) file\n" ));
2863 IF_DEBUG(linker,debugBelch( "Architecture is " ));
2864 switch (ehdr->e_machine) {
2865 case EM_386: IF_DEBUG(linker,debugBelch( "x86" )); break;
2866 #ifdef EM_SPARC32PLUS
2867 case EM_SPARC32PLUS:
2869 case EM_SPARC: IF_DEBUG(linker,debugBelch( "sparc" )); break;
2871 case EM_IA_64: IF_DEBUG(linker,debugBelch( "ia64" )); break;
2873 case EM_PPC: IF_DEBUG(linker,debugBelch( "powerpc32" )); break;
2875 case EM_X86_64: IF_DEBUG(linker,debugBelch( "x86_64" )); break;
2876 #elif defined(EM_AMD64)
2877 case EM_AMD64: IF_DEBUG(linker,debugBelch( "amd64" )); break;
2879 default: IF_DEBUG(linker,debugBelch( "unknown" ));
2880 errorBelch("%s: unknown architecture (e_machine == %d)"
2881 , oc->fileName, ehdr->e_machine);
2885 IF_DEBUG(linker,debugBelch(
2886 "\nSection header table: start %ld, n_entries %d, ent_size %d\n",
2887 (long)ehdr->e_shoff, ehdr->e_shnum, ehdr->e_shentsize ));
2889 ASSERT (ehdr->e_shentsize == sizeof(Elf_Shdr));
2891 shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
2893 if (ehdr->e_shstrndx == SHN_UNDEF) {
2894 errorBelch("%s: no section header string table", oc->fileName);
2897 IF_DEBUG(linker,debugBelch( "Section header string table is section %d\n",
2899 sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
2902 for (i = 0; i < ehdr->e_shnum; i++) {
2903 IF_DEBUG(linker,debugBelch("%2d: ", i ));
2904 IF_DEBUG(linker,debugBelch("type=%2d ", (int)shdr[i].sh_type ));
2905 IF_DEBUG(linker,debugBelch("size=%4d ", (int)shdr[i].sh_size ));
2906 IF_DEBUG(linker,debugBelch("offs=%4d ", (int)shdr[i].sh_offset ));
2907 IF_DEBUG(linker,debugBelch(" (%p .. %p) ",
2908 ehdrC + shdr[i].sh_offset,
2909 ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1));
2911 if (shdr[i].sh_type == SHT_REL) {
2912 IF_DEBUG(linker,debugBelch("Rel " ));
2913 } else if (shdr[i].sh_type == SHT_RELA) {
2914 IF_DEBUG(linker,debugBelch("RelA " ));
2916 IF_DEBUG(linker,debugBelch(" "));
2919 IF_DEBUG(linker,debugBelch("sname=%s\n", sh_strtab + shdr[i].sh_name ));
2923 IF_DEBUG(linker,debugBelch( "\nString tables" ));
2926 for (i = 0; i < ehdr->e_shnum; i++) {
2927 if (shdr[i].sh_type == SHT_STRTAB
2928 /* Ignore the section header's string table. */
2929 && i != ehdr->e_shstrndx
2930 /* Ignore string tables named .stabstr, as they contain
2932 && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
2934 IF_DEBUG(linker,debugBelch(" section %d is a normal string table", i ));
2935 strtab = ehdrC + shdr[i].sh_offset;
2940 errorBelch("%s: no string tables, or too many", oc->fileName);
2945 IF_DEBUG(linker,debugBelch( "\nSymbol tables" ));
2946 for (i = 0; i < ehdr->e_shnum; i++) {
2947 if (shdr[i].sh_type != SHT_SYMTAB) continue;
2948 IF_DEBUG(linker,debugBelch( "section %d is a symbol table\n", i ));
2950 stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
2951 nent = shdr[i].sh_size / sizeof(Elf_Sym);
2952 IF_DEBUG(linker,debugBelch( " number of entries is apparently %d (%ld rem)\n",
2954 (long)shdr[i].sh_size % sizeof(Elf_Sym)
2956 if (0 != shdr[i].sh_size % sizeof(Elf_Sym)) {
2957 errorBelch("%s: non-integral number of symbol table entries", oc->fileName);
2960 for (j = 0; j < nent; j++) {
2961 IF_DEBUG(linker,debugBelch(" %2d ", j ));
2962 IF_DEBUG(linker,debugBelch(" sec=%-5d size=%-3d val=%5p ",
2963 (int)stab[j].st_shndx,
2964 (int)stab[j].st_size,
2965 (char*)stab[j].st_value ));
2967 IF_DEBUG(linker,debugBelch("type=" ));
2968 switch (ELF_ST_TYPE(stab[j].st_info)) {
2969 case STT_NOTYPE: IF_DEBUG(linker,debugBelch("notype " )); break;
2970 case STT_OBJECT: IF_DEBUG(linker,debugBelch("object " )); break;
2971 case STT_FUNC : IF_DEBUG(linker,debugBelch("func " )); break;
2972 case STT_SECTION: IF_DEBUG(linker,debugBelch("section" )); break;
2973 case STT_FILE: IF_DEBUG(linker,debugBelch("file " )); break;
2974 default: IF_DEBUG(linker,debugBelch("? " )); break;
2976 IF_DEBUG(linker,debugBelch(" " ));
2978 IF_DEBUG(linker,debugBelch("bind=" ));
2979 switch (ELF_ST_BIND(stab[j].st_info)) {
2980 case STB_LOCAL : IF_DEBUG(linker,debugBelch("local " )); break;
2981 case STB_GLOBAL: IF_DEBUG(linker,debugBelch("global" )); break;
2982 case STB_WEAK : IF_DEBUG(linker,debugBelch("weak " )); break;
2983 default: IF_DEBUG(linker,debugBelch("? " )); break;
2985 IF_DEBUG(linker,debugBelch(" " ));
2987 IF_DEBUG(linker,debugBelch("name=%s\n", strtab + stab[j].st_name ));
2991 if (nsymtabs == 0) {
2992 errorBelch("%s: didn't find any symbol tables", oc->fileName);
2999 static int getSectionKind_ELF( Elf_Shdr *hdr, int *is_bss )
3003 if (hdr->sh_type == SHT_PROGBITS
3004 && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_EXECINSTR)) {
3005 /* .text-style section */
3006 return SECTIONKIND_CODE_OR_RODATA;
3009 if (hdr->sh_type == SHT_PROGBITS
3010 && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
3011 /* .data-style section */
3012 return SECTIONKIND_RWDATA;
3015 if (hdr->sh_type == SHT_PROGBITS
3016 && (hdr->sh_flags & SHF_ALLOC) && !(hdr->sh_flags & SHF_WRITE)) {
3017 /* .rodata-style section */
3018 return SECTIONKIND_CODE_OR_RODATA;
3021 if (hdr->sh_type == SHT_NOBITS
3022 && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
3023 /* .bss-style section */
3025 return SECTIONKIND_RWDATA;
3028 return SECTIONKIND_OTHER;
3033 ocGetNames_ELF ( ObjectCode* oc )
3038 char* ehdrC = (char*)(oc->image);
3039 Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
3040 char* strtab = findElfSection ( ehdrC, SHT_STRTAB );
3041 Elf_Shdr* shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
3043 ASSERT(symhash != NULL);
3046 errorBelch("%s: no strtab", oc->fileName);
3051 for (i = 0; i < ehdr->e_shnum; i++) {
3052 /* Figure out what kind of section it is. Logic derived from
3053 Figure 1.14 ("Special Sections") of the ELF document
3054 ("Portable Formats Specification, Version 1.1"). */
3056 SectionKind kind = getSectionKind_ELF(&shdr[i], &is_bss);
3058 if (is_bss && shdr[i].sh_size > 0) {
3059 /* This is a non-empty .bss section. Allocate zeroed space for
3060 it, and set its .sh_offset field such that
3061 ehdrC + .sh_offset == addr_of_zeroed_space. */
3062 char* zspace = stgCallocBytes(1, shdr[i].sh_size,
3063 "ocGetNames_ELF(BSS)");
3064 shdr[i].sh_offset = ((char*)zspace) - ((char*)ehdrC);
3066 debugBelch("BSS section at 0x%x, size %d\n",
3067 zspace, shdr[i].sh_size);
3071 /* fill in the section info */
3072 if (kind != SECTIONKIND_OTHER && shdr[i].sh_size > 0) {
3073 addProddableBlock(oc, ehdrC + shdr[i].sh_offset, shdr[i].sh_size);
3074 addSection(oc, kind, ehdrC + shdr[i].sh_offset,
3075 ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1);
3078 if (shdr[i].sh_type != SHT_SYMTAB) continue;
3080 /* copy stuff into this module's object symbol table */
3081 stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
3082 nent = shdr[i].sh_size / sizeof(Elf_Sym);
3084 oc->n_symbols = nent;
3085 oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
3086 "ocGetNames_ELF(oc->symbols)");
3088 for (j = 0; j < nent; j++) {
3090 char isLocal = FALSE; /* avoids uninit-var warning */
3092 char* nm = strtab + stab[j].st_name;
3093 int secno = stab[j].st_shndx;
3095 /* Figure out if we want to add it; if so, set ad to its
3096 address. Otherwise leave ad == NULL. */
3098 if (secno == SHN_COMMON) {
3100 ad = stgCallocBytes(1, stab[j].st_size, "ocGetNames_ELF(COMMON)");
3102 debugBelch("COMMON symbol, size %d name %s\n",
3103 stab[j].st_size, nm);
3105 /* Pointless to do addProddableBlock() for this area,
3106 since the linker should never poke around in it. */
3109 if ( ( ELF_ST_BIND(stab[j].st_info)==STB_GLOBAL
3110 || ELF_ST_BIND(stab[j].st_info)==STB_LOCAL
3112 /* and not an undefined symbol */
3113 && stab[j].st_shndx != SHN_UNDEF
3114 /* and not in a "special section" */
3115 && stab[j].st_shndx < SHN_LORESERVE
3117 /* and it's a not a section or string table or anything silly */
3118 ( ELF_ST_TYPE(stab[j].st_info)==STT_FUNC ||
3119 ELF_ST_TYPE(stab[j].st_info)==STT_OBJECT ||
3120 ELF_ST_TYPE(stab[j].st_info)==STT_NOTYPE
3123 /* Section 0 is the undefined section, hence > and not >=. */
3124 ASSERT(secno > 0 && secno < ehdr->e_shnum);
3126 if (shdr[secno].sh_type == SHT_NOBITS) {
3127 debugBelch(" BSS symbol, size %d off %d name %s\n",
3128 stab[j].st_size, stab[j].st_value, nm);
3131 ad = ehdrC + shdr[ secno ].sh_offset + stab[j].st_value;
3132 if (ELF_ST_BIND(stab[j].st_info)==STB_LOCAL) {
3135 #ifdef ELF_FUNCTION_DESC
3136 /* dlsym() and the initialisation table both give us function
3137 * descriptors, so to be consistent we store function descriptors
3138 * in the symbol table */
3139 if (ELF_ST_TYPE(stab[j].st_info) == STT_FUNC)
3140 ad = (char *)allocateFunctionDesc((Elf_Addr)ad);
3142 IF_DEBUG(linker,debugBelch( "addOTabName(GLOB): %10p %s %s\n",
3143 ad, oc->fileName, nm ));
3148 /* And the decision is ... */
3152 oc->symbols[j] = nm;
3155 /* Ignore entirely. */
3157 ghciInsertStrHashTable(oc->fileName, symhash, nm, ad);
3161 IF_DEBUG(linker,debugBelch( "skipping `%s'\n",
3162 strtab + stab[j].st_name ));
3165 "skipping bind = %d, type = %d, shndx = %d `%s'\n",
3166 (int)ELF_ST_BIND(stab[j].st_info),
3167 (int)ELF_ST_TYPE(stab[j].st_info),
3168 (int)stab[j].st_shndx,
3169 strtab + stab[j].st_name
3172 oc->symbols[j] = NULL;
3181 /* Do ELF relocations which lack an explicit addend. All x86-linux
3182 relocations appear to be of this form. */
3184 do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
3185 Elf_Shdr* shdr, int shnum,
3186 Elf_Sym* stab, char* strtab )
3191 Elf_Rel* rtab = (Elf_Rel*) (ehdrC + shdr[shnum].sh_offset);
3192 int nent = shdr[shnum].sh_size / sizeof(Elf_Rel);
3193 int target_shndx = shdr[shnum].sh_info;
3194 int symtab_shndx = shdr[shnum].sh_link;
3196 stab = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
3197 targ = (Elf_Word*)(ehdrC + shdr[ target_shndx ].sh_offset);
3198 IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
3199 target_shndx, symtab_shndx ));
3201 /* Skip sections that we're not interested in. */
3204 SectionKind kind = getSectionKind_ELF(&shdr[target_shndx], &is_bss);
3205 if (kind == SECTIONKIND_OTHER) {
3206 IF_DEBUG(linker,debugBelch( "skipping (target section not loaded)"));
3211 for (j = 0; j < nent; j++) {
3212 Elf_Addr offset = rtab[j].r_offset;
3213 Elf_Addr info = rtab[j].r_info;
3215 Elf_Addr P = ((Elf_Addr)targ) + offset;
3216 Elf_Word* pP = (Elf_Word*)P;
3221 StgStablePtr stablePtr;
3224 IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p)",
3225 j, (void*)offset, (void*)info ));
3227 IF_DEBUG(linker,debugBelch( " ZERO" ));
3230 Elf_Sym sym = stab[ELF_R_SYM(info)];
3231 /* First see if it is a local symbol. */
3232 if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
3233 /* Yes, so we can get the address directly from the ELF symbol
3235 symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
3237 (ehdrC + shdr[ sym.st_shndx ].sh_offset
3238 + stab[ELF_R_SYM(info)].st_value);
3241 symbol = strtab + sym.st_name;
3242 stablePtr = (StgStablePtr)lookupHashTable(stablehash, (StgWord)symbol);
3243 if (NULL == stablePtr) {
3244 /* No, so look up the name in our global table. */
3245 S_tmp = lookupSymbol( symbol );
3246 S = (Elf_Addr)S_tmp;
3248 stableVal = deRefStablePtr( stablePtr );
3250 S = (Elf_Addr)S_tmp;
3254 errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
3257 IF_DEBUG(linker,debugBelch( "`%s' resolves to %p\n", symbol, (void*)S ));
3260 IF_DEBUG(linker,debugBelch( "Reloc: P = %p S = %p A = %p\n",
3261 (void*)P, (void*)S, (void*)A ));
3262 checkProddableBlock ( oc, pP );
3266 switch (ELF_R_TYPE(info)) {
3267 # ifdef i386_HOST_ARCH
3268 case R_386_32: *pP = value; break;
3269 case R_386_PC32: *pP = value - P; break;
3272 errorBelch("%s: unhandled ELF relocation(Rel) type %lu\n",
3273 oc->fileName, (lnat)ELF_R_TYPE(info));
3281 /* Do ELF relocations for which explicit addends are supplied.
3282 sparc-solaris relocations appear to be of this form. */
3284 do_Elf_Rela_relocations ( ObjectCode* oc, char* ehdrC,
3285 Elf_Shdr* shdr, int shnum,
3286 Elf_Sym* stab, char* strtab )
3289 char *symbol = NULL;
3291 Elf_Rela* rtab = (Elf_Rela*) (ehdrC + shdr[shnum].sh_offset);
3292 int nent = shdr[shnum].sh_size / sizeof(Elf_Rela);
3293 int target_shndx = shdr[shnum].sh_info;
3294 int symtab_shndx = shdr[shnum].sh_link;
3296 stab = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
3297 targ = (Elf_Addr) (ehdrC + shdr[ target_shndx ].sh_offset);
3298 IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
3299 target_shndx, symtab_shndx ));
3301 for (j = 0; j < nent; j++) {
3302 #if defined(DEBUG) || defined(sparc_HOST_ARCH) || defined(ia64_HOST_ARCH) || defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
3303 /* This #ifdef only serves to avoid unused-var warnings. */
3304 Elf_Addr offset = rtab[j].r_offset;
3305 Elf_Addr P = targ + offset;
3307 Elf_Addr info = rtab[j].r_info;
3308 Elf_Addr A = rtab[j].r_addend;
3312 # if defined(sparc_HOST_ARCH)
3313 Elf_Word* pP = (Elf_Word*)P;
3315 # elif defined(ia64_HOST_ARCH)
3316 Elf64_Xword *pP = (Elf64_Xword *)P;
3318 # elif defined(powerpc_HOST_ARCH)
3322 IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p %6p) ",
3323 j, (void*)offset, (void*)info,
3326 IF_DEBUG(linker,debugBelch( " ZERO" ));
3329 Elf_Sym sym = stab[ELF_R_SYM(info)];
3330 /* First see if it is a local symbol. */
3331 if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
3332 /* Yes, so we can get the address directly from the ELF symbol
3334 symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
3336 (ehdrC + shdr[ sym.st_shndx ].sh_offset
3337 + stab[ELF_R_SYM(info)].st_value);
3338 #ifdef ELF_FUNCTION_DESC
3339 /* Make a function descriptor for this function */
3340 if (S && ELF_ST_TYPE(sym.st_info) == STT_FUNC) {
3341 S = allocateFunctionDesc(S + A);
3346 /* No, so look up the name in our global table. */
3347 symbol = strtab + sym.st_name;
3348 S_tmp = lookupSymbol( symbol );
3349 S = (Elf_Addr)S_tmp;
3351 #ifdef ELF_FUNCTION_DESC
3352 /* If a function, already a function descriptor - we would
3353 have to copy it to add an offset. */
3354 if (S && (ELF_ST_TYPE(sym.st_info) == STT_FUNC) && (A != 0))
3355 errorBelch("%s: function %s with addend %p", oc->fileName, symbol, (void *)A);
3359 errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
3362 IF_DEBUG(linker,debugBelch( "`%s' resolves to %p", symbol, (void*)S ));
3365 IF_DEBUG(linker,debugBelch("Reloc: P = %p S = %p A = %p\n",
3366 (void*)P, (void*)S, (void*)A ));
3367 /* checkProddableBlock ( oc, (void*)P ); */
3371 switch (ELF_R_TYPE(info)) {
3372 # if defined(sparc_HOST_ARCH)
3373 case R_SPARC_WDISP30:
3374 w1 = *pP & 0xC0000000;
3375 w2 = (Elf_Word)((value - P) >> 2);
3376 ASSERT((w2 & 0xC0000000) == 0);
3381 w1 = *pP & 0xFFC00000;
3382 w2 = (Elf_Word)(value >> 10);
3383 ASSERT((w2 & 0xFFC00000) == 0);
3389 w2 = (Elf_Word)(value & 0x3FF);
3390 ASSERT((w2 & ~0x3FF) == 0);
3394 /* According to the Sun documentation:
3396 This relocation type resembles R_SPARC_32, except it refers to an
3397 unaligned word. That is, the word to be relocated must be treated
3398 as four separate bytes with arbitrary alignment, not as a word
3399 aligned according to the architecture requirements.
3401 (JRS: which means that freeloading on the R_SPARC_32 case
3402 is probably wrong, but hey ...)
3406 w2 = (Elf_Word)value;
3409 # elif defined(ia64_HOST_ARCH)
3410 case R_IA64_DIR64LSB:
3411 case R_IA64_FPTR64LSB:
3414 case R_IA64_PCREL64LSB:
3417 case R_IA64_SEGREL64LSB:
3418 addr = findElfSegment(ehdrC, value);
3421 case R_IA64_GPREL22:
3422 ia64_reloc_gprel22(P, value);
3424 case R_IA64_LTOFF22:
3425 case R_IA64_LTOFF22X:
3426 case R_IA64_LTOFF_FPTR22:
3427 addr = allocateGOTEntry(value);
3428 ia64_reloc_gprel22(P, addr);
3430 case R_IA64_PCREL21B:
3431 ia64_reloc_pcrel21(P, S, oc);
3434 /* This goes with R_IA64_LTOFF22X and points to the load to
3435 * convert into a move. We don't implement relaxation. */
3437 # elif defined(powerpc_HOST_ARCH)
3438 case R_PPC_ADDR16_LO:
3439 *(Elf32_Half*) P = value;
3442 case R_PPC_ADDR16_HI:
3443 *(Elf32_Half*) P = value >> 16;
3446 case R_PPC_ADDR16_HA:
3447 *(Elf32_Half*) P = (value + 0x8000) >> 16;
3451 *(Elf32_Word *) P = value;
3455 *(Elf32_Word *) P = value - P;
3461 if( delta << 6 >> 6 != delta )
3463 value = (Elf_Addr) (&makeSymbolExtra( oc, ELF_R_SYM(info), value )
3467 if( value == 0 || delta << 6 >> 6 != delta )
3469 barf( "Unable to make SymbolExtra for #%d",
3475 *(Elf_Word *) P = (*(Elf_Word *) P & 0xfc000003)
3476 | (delta & 0x3fffffc);
3480 #if x86_64_HOST_ARCH
3482 *(Elf64_Xword *)P = value;
3487 StgInt64 off = value - P;
3488 if (off >= 0x7fffffffL || off < -0x80000000L) {
3489 #if X86_64_ELF_NONPIC_HACK
3490 StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3492 off = pltAddress + A - P;
3494 barf("R_X86_64_PC32 relocation out of range: %s = %p\nRecompile %s with -fPIC.",
3495 symbol, off, oc->fileName );
3498 *(Elf64_Word *)P = (Elf64_Word)off;
3504 StgInt64 off = value - P;
3505 *(Elf64_Word *)P = (Elf64_Word)off;
3510 if (value >= 0x7fffffffL) {
3511 #if X86_64_ELF_NONPIC_HACK
3512 StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3514 value = pltAddress + A;
3516 barf("R_X86_64_32 relocation out of range: %s = %p\nRecompile %s with -fPIC.",
3517 symbol, value, oc->fileName );
3520 *(Elf64_Word *)P = (Elf64_Word)value;
3524 if ((StgInt64)value > 0x7fffffffL || (StgInt64)value < -0x80000000L) {
3525 #if X86_64_ELF_NONPIC_HACK
3526 StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3528 value = pltAddress + A;
3530 barf("R_X86_64_32S relocation out of range: %s = %p\nRecompile %s with -fPIC.",
3531 symbol, value, oc->fileName );
3534 *(Elf64_Sword *)P = (Elf64_Sword)value;
3537 case R_X86_64_GOTPCREL:
3539 StgInt64 gotAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)->addr;
3540 StgInt64 off = gotAddress + A - P;
3541 *(Elf64_Word *)P = (Elf64_Word)off;
3545 case R_X86_64_PLT32:
3547 StgInt64 off = value - P;
3548 if (off >= 0x7fffffffL || off < -0x80000000L) {
3549 StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3551 off = pltAddress + A - P;
3553 *(Elf64_Word *)P = (Elf64_Word)off;
3559 errorBelch("%s: unhandled ELF relocation(RelA) type %lu\n",
3560 oc->fileName, (lnat)ELF_R_TYPE(info));
3569 ocResolve_ELF ( ObjectCode* oc )
3573 Elf_Sym* stab = NULL;
3574 char* ehdrC = (char*)(oc->image);
3575 Elf_Ehdr* ehdr = (Elf_Ehdr*) ehdrC;
3576 Elf_Shdr* shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
3578 /* first find "the" symbol table */
3579 stab = (Elf_Sym*) findElfSection ( ehdrC, SHT_SYMTAB );
3581 /* also go find the string table */
3582 strtab = findElfSection ( ehdrC, SHT_STRTAB );
3584 if (stab == NULL || strtab == NULL) {
3585 errorBelch("%s: can't find string or symbol table", oc->fileName);
3589 /* Process the relocation sections. */
3590 for (shnum = 0; shnum < ehdr->e_shnum; shnum++) {
3591 if (shdr[shnum].sh_type == SHT_REL) {
3592 ok = do_Elf_Rel_relocations ( oc, ehdrC, shdr,
3593 shnum, stab, strtab );
3597 if (shdr[shnum].sh_type == SHT_RELA) {
3598 ok = do_Elf_Rela_relocations ( oc, ehdrC, shdr,
3599 shnum, stab, strtab );
3604 #if defined(powerpc_HOST_ARCH)
3605 ocFlushInstructionCache( oc );
3613 * Instructions are 41 bits long, packed into 128 bit bundles with a 5-bit template
3614 * at the front. The following utility functions pack and unpack instructions, and
3615 * take care of the most common relocations.
3618 #ifdef ia64_HOST_ARCH
3621 ia64_extract_instruction(Elf64_Xword *target)
3624 int slot = (Elf_Addr)target & 3;
3625 target = (Elf_Addr)target & ~3;
3633 return ((w1 >> 5) & 0x1ffffffffff);
3635 return (w1 >> 46) | ((w2 & 0x7fffff) << 18);
3639 barf("ia64_extract_instruction: invalid slot %p", target);
3644 ia64_deposit_instruction(Elf64_Xword *target, Elf64_Xword value)
3646 int slot = (Elf_Addr)target & 3;
3647 target = (Elf_Addr)target & ~3;
3652 *target |= value << 5;
3655 *target |= value << 46;
3656 *(target+1) |= value >> 18;
3659 *(target+1) |= value << 23;
3665 ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value)
3667 Elf64_Xword instruction;
3668 Elf64_Sxword rel_value;
3670 rel_value = value - gp_val;
3671 if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff))
3672 barf("GP-relative data out of range (address = 0x%lx, gp = 0x%lx)", value, gp_val);
3674 instruction = ia64_extract_instruction((Elf64_Xword *)target);
3675 instruction |= (((rel_value >> 0) & 0x07f) << 13) /* imm7b */
3676 | (((rel_value >> 7) & 0x1ff) << 27) /* imm9d */
3677 | (((rel_value >> 16) & 0x01f) << 22) /* imm5c */
3678 | ((Elf64_Xword)(rel_value < 0) << 36); /* s */
3679 ia64_deposit_instruction((Elf64_Xword *)target, instruction);
3683 ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc)
3685 Elf64_Xword instruction;
3686 Elf64_Sxword rel_value;
3689 entry = allocatePLTEntry(value, oc);
3691 rel_value = (entry >> 4) - (target >> 4);
3692 if ((rel_value > 0xfffff) || (rel_value < -0xfffff))
3693 barf("PLT entry too far away (entry = 0x%lx, target = 0x%lx)", entry, target);
3695 instruction = ia64_extract_instruction((Elf64_Xword *)target);
3696 instruction |= ((rel_value & 0xfffff) << 13) /* imm20b */
3697 | ((Elf64_Xword)(rel_value < 0) << 36); /* s */
3698 ia64_deposit_instruction((Elf64_Xword *)target, instruction);
3704 * PowerPC & X86_64 ELF specifics
3707 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
3709 static int ocAllocateSymbolExtras_ELF( ObjectCode *oc )
3715 ehdr = (Elf_Ehdr *) oc->image;
3716 shdr = (Elf_Shdr *) ( ((char *)oc->image) + ehdr->e_shoff );
3718 for( i = 0; i < ehdr->e_shnum; i++ )
3719 if( shdr[i].sh_type == SHT_SYMTAB )
3722 if( i == ehdr->e_shnum )
3724 errorBelch( "This ELF file contains no symtab" );
3728 if( shdr[i].sh_entsize != sizeof( Elf_Sym ) )
3730 errorBelch( "The entry size (%d) of the symtab isn't %d\n",
3731 (int) shdr[i].sh_entsize, (int) sizeof( Elf_Sym ) );
3736 return ocAllocateSymbolExtras( oc, shdr[i].sh_size / sizeof( Elf_Sym ), 0 );
3739 #endif /* powerpc */
3743 /* --------------------------------------------------------------------------
3745 * ------------------------------------------------------------------------*/
3747 #if defined(OBJFORMAT_MACHO)
3750 Support for MachO linking on Darwin/MacOS X
3751 by Wolfgang Thaller (wolfgang.thaller@gmx.net)
3753 I hereby formally apologize for the hackish nature of this code.
3754 Things that need to be done:
3755 *) implement ocVerifyImage_MachO
3756 *) add still more sanity checks.
3759 #if x86_64_HOST_ARCH || powerpc64_HOST_ARCH
3760 #define mach_header mach_header_64
3761 #define segment_command segment_command_64
3762 #define section section_64
3763 #define nlist nlist_64
3766 #ifdef powerpc_HOST_ARCH
3767 static int ocAllocateSymbolExtras_MachO(ObjectCode* oc)
3769 struct mach_header *header = (struct mach_header *) oc->image;
3770 struct load_command *lc = (struct load_command *) (header + 1);
3773 for( i = 0; i < header->ncmds; i++ )
3775 if( lc->cmd == LC_SYMTAB )
3777 // Find out the first and last undefined external
3778 // symbol, so we don't have to allocate too many
3780 struct symtab_command *symLC = (struct symtab_command *) lc;
3781 unsigned min = symLC->nsyms, max = 0;
3782 struct nlist *nlist =
3783 symLC ? (struct nlist*) ((char*) oc->image + symLC->symoff)
3785 for(i=0;i<symLC->nsyms;i++)
3787 if(nlist[i].n_type & N_STAB)
3789 else if(nlist[i].n_type & N_EXT)
3791 if((nlist[i].n_type & N_TYPE) == N_UNDF
3792 && (nlist[i].n_value == 0))
3802 return ocAllocateSymbolExtras(oc, max - min + 1, min);
3807 lc = (struct load_command *) ( ((char *)lc) + lc->cmdsize );
3809 return ocAllocateSymbolExtras(oc,0,0);
3812 #ifdef x86_64_HOST_ARCH
3813 static int ocAllocateSymbolExtras_MachO(ObjectCode* oc)
3815 struct mach_header *header = (struct mach_header *) oc->image;
3816 struct load_command *lc = (struct load_command *) (header + 1);
3819 for( i = 0; i < header->ncmds; i++ )
3821 if( lc->cmd == LC_SYMTAB )
3823 // Just allocate one entry for every symbol
3824 struct symtab_command *symLC = (struct symtab_command *) lc;
3826 return ocAllocateSymbolExtras(oc, symLC->nsyms, 0);
3829 lc = (struct load_command *) ( ((char *)lc) + lc->cmdsize );
3831 return ocAllocateSymbolExtras(oc,0,0);
3835 static int ocVerifyImage_MachO(ObjectCode* oc)
3837 char *image = (char*) oc->image;
3838 struct mach_header *header = (struct mach_header*) image;
3840 #if x86_64_TARGET_ARCH || powerpc64_TARGET_ARCH
3841 if(header->magic != MH_MAGIC_64)
3844 if(header->magic != MH_MAGIC)
3847 // FIXME: do some more verifying here
3851 static int resolveImports(
3854 struct symtab_command *symLC,
3855 struct section *sect, // ptr to lazy or non-lazy symbol pointer section
3856 unsigned long *indirectSyms,
3857 struct nlist *nlist)
3860 size_t itemSize = 4;
3863 int isJumpTable = 0;
3864 if(!strcmp(sect->sectname,"__jump_table"))
3868 ASSERT(sect->reserved2 == itemSize);
3872 for(i=0; i*itemSize < sect->size;i++)
3874 // according to otool, reserved1 contains the first index into the indirect symbol table
3875 struct nlist *symbol = &nlist[indirectSyms[sect->reserved1+i]];
3876 char *nm = image + symLC->stroff + symbol->n_un.n_strx;
3879 if((symbol->n_type & N_TYPE) == N_UNDF
3880 && (symbol->n_type & N_EXT) && (symbol->n_value != 0))
3881 addr = (void*) (symbol->n_value);
3883 addr = lookupSymbol(nm);
3886 errorBelch("\n%s: unknown symbol `%s'", oc->fileName, nm);
3894 checkProddableBlock(oc,image + sect->offset + i*itemSize);
3895 *(image + sect->offset + i*itemSize) = 0xe9; // jmp
3896 *(unsigned*)(image + sect->offset + i*itemSize + 1)
3897 = (char*)addr - (image + sect->offset + i*itemSize + 5);
3902 checkProddableBlock(oc,((void**)(image + sect->offset)) + i);
3903 ((void**)(image + sect->offset))[i] = addr;
3910 static unsigned long relocateAddress(
3913 struct section* sections,
3914 unsigned long address)
3917 for(i = 0; i < nSections; i++)
3919 if(sections[i].addr <= address
3920 && address < sections[i].addr + sections[i].size)
3922 return (unsigned long)oc->image
3923 + sections[i].offset + address - sections[i].addr;
3926 barf("Invalid Mach-O file:"
3927 "Address out of bounds while relocating object file");
3931 static int relocateSection(
3934 struct symtab_command *symLC, struct nlist *nlist,
3935 int nSections, struct section* sections, struct section *sect)
3937 struct relocation_info *relocs;
3940 if(!strcmp(sect->sectname,"__la_symbol_ptr"))
3942 else if(!strcmp(sect->sectname,"__nl_symbol_ptr"))
3944 else if(!strcmp(sect->sectname,"__la_sym_ptr2"))
3946 else if(!strcmp(sect->sectname,"__la_sym_ptr3"))
3950 relocs = (struct relocation_info*) (image + sect->reloff);
3954 #ifdef x86_64_HOST_ARCH
3955 struct relocation_info *reloc = &relocs[i];
3957 char *thingPtr = image + sect->offset + reloc->r_address;
3961 int type = reloc->r_type;
3963 checkProddableBlock(oc,thingPtr);
3964 switch(reloc->r_length)
3967 thing = *(uint8_t*)thingPtr;
3968 baseValue = (uint64_t)thingPtr + 1;
3971 thing = *(uint16_t*)thingPtr;
3972 baseValue = (uint64_t)thingPtr + 2;
3975 thing = *(uint32_t*)thingPtr;
3976 baseValue = (uint64_t)thingPtr + 4;
3979 thing = *(uint64_t*)thingPtr;
3980 baseValue = (uint64_t)thingPtr + 8;
3983 barf("Unknown size.");
3986 if(type == X86_64_RELOC_GOT
3987 || type == X86_64_RELOC_GOT_LOAD)
3989 ASSERT(reloc->r_extern);
3990 value = (uint64_t) &makeSymbolExtra(oc, reloc->r_symbolnum, value)->addr;
3992 type = X86_64_RELOC_SIGNED;
3994 else if(reloc->r_extern)
3996 struct nlist *symbol = &nlist[reloc->r_symbolnum];
3997 char *nm = image + symLC->stroff + symbol->n_un.n_strx;
3998 if(symbol->n_value == 0)
3999 value = (uint64_t) lookupSymbol(nm);
4001 value = relocateAddress(oc, nSections, sections,
4006 value = sections[reloc->r_symbolnum-1].offset
4007 - sections[reloc->r_symbolnum-1].addr
4011 if(type == X86_64_RELOC_BRANCH)
4013 if((int32_t)(value - baseValue) != (int64_t)(value - baseValue))
4015 ASSERT(reloc->r_extern);
4016 value = (uint64_t) &makeSymbolExtra(oc, reloc->r_symbolnum, value)
4019 ASSERT((int32_t)(value - baseValue) == (int64_t)(value - baseValue));
4020 type = X86_64_RELOC_SIGNED;
4025 case X86_64_RELOC_UNSIGNED:
4026 ASSERT(!reloc->r_pcrel);
4029 case X86_64_RELOC_SIGNED:
4030 ASSERT(reloc->r_pcrel);
4031 thing += value - baseValue;
4033 case X86_64_RELOC_SUBTRACTOR:
4034 ASSERT(!reloc->r_pcrel);
4038 barf("unkown relocation");
4041 switch(reloc->r_length)
4044 *(uint8_t*)thingPtr = thing;
4047 *(uint16_t*)thingPtr = thing;
4050 *(uint32_t*)thingPtr = thing;
4053 *(uint64_t*)thingPtr = thing;
4057 if(relocs[i].r_address & R_SCATTERED)
4059 struct scattered_relocation_info *scat =
4060 (struct scattered_relocation_info*) &relocs[i];
4064 if(scat->r_length == 2)
4066 unsigned long word = 0;
4067 unsigned long* wordPtr = (unsigned long*) (image + sect->offset + scat->r_address);
4068 checkProddableBlock(oc,wordPtr);
4070 // Note on relocation types:
4071 // i386 uses the GENERIC_RELOC_* types,
4072 // while ppc uses special PPC_RELOC_* types.
4073 // *_RELOC_VANILLA and *_RELOC_PAIR have the same value
4074 // in both cases, all others are different.
4075 // Therefore, we use GENERIC_RELOC_VANILLA
4076 // and GENERIC_RELOC_PAIR instead of the PPC variants,
4077 // and use #ifdefs for the other types.
4079 // Step 1: Figure out what the relocated value should be
4080 if(scat->r_type == GENERIC_RELOC_VANILLA)
4082 word = *wordPtr + (unsigned long) relocateAddress(
4089 #ifdef powerpc_HOST_ARCH
4090 else if(scat->r_type == PPC_RELOC_SECTDIFF
4091 || scat->r_type == PPC_RELOC_LO16_SECTDIFF
4092 || scat->r_type == PPC_RELOC_HI16_SECTDIFF
4093 || scat->r_type == PPC_RELOC_HA16_SECTDIFF)
4095 else if(scat->r_type == GENERIC_RELOC_SECTDIFF)
4098 struct scattered_relocation_info *pair =
4099 (struct scattered_relocation_info*) &relocs[i+1];
4101 if(!pair->r_scattered || pair->r_type != GENERIC_RELOC_PAIR)
4102 barf("Invalid Mach-O file: "
4103 "RELOC_*_SECTDIFF not followed by RELOC_PAIR");
4105 word = (unsigned long)
4106 (relocateAddress(oc, nSections, sections, scat->r_value)
4107 - relocateAddress(oc, nSections, sections, pair->r_value));
4110 #ifdef powerpc_HOST_ARCH
4111 else if(scat->r_type == PPC_RELOC_HI16
4112 || scat->r_type == PPC_RELOC_LO16
4113 || scat->r_type == PPC_RELOC_HA16
4114 || scat->r_type == PPC_RELOC_LO14)
4115 { // these are generated by label+offset things
4116 struct relocation_info *pair = &relocs[i+1];
4117 if((pair->r_address & R_SCATTERED) || pair->r_type != PPC_RELOC_PAIR)
4118 barf("Invalid Mach-O file: "
4119 "PPC_RELOC_* not followed by PPC_RELOC_PAIR");
4121 if(scat->r_type == PPC_RELOC_LO16)
4123 word = ((unsigned short*) wordPtr)[1];
4124 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4126 else if(scat->r_type == PPC_RELOC_LO14)
4128 barf("Unsupported Relocation: PPC_RELOC_LO14");
4129 word = ((unsigned short*) wordPtr)[1] & 0xFFFC;
4130 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4132 else if(scat->r_type == PPC_RELOC_HI16)
4134 word = ((unsigned short*) wordPtr)[1] << 16;
4135 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
4137 else if(scat->r_type == PPC_RELOC_HA16)
4139 word = ((unsigned short*) wordPtr)[1] << 16;
4140 word += ((short)relocs[i+1].r_address & (short)0xFFFF);
4144 word += (unsigned long) relocateAddress(oc, nSections, sections, scat->r_value)
4151 continue; // ignore the others
4153 #ifdef powerpc_HOST_ARCH
4154 if(scat->r_type == GENERIC_RELOC_VANILLA
4155 || scat->r_type == PPC_RELOC_SECTDIFF)
4157 if(scat->r_type == GENERIC_RELOC_VANILLA
4158 || scat->r_type == GENERIC_RELOC_SECTDIFF)
4163 #ifdef powerpc_HOST_ARCH
4164 else if(scat->r_type == PPC_RELOC_LO16_SECTDIFF || scat->r_type == PPC_RELOC_LO16)
4166 ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
4168 else if(scat->r_type == PPC_RELOC_HI16_SECTDIFF || scat->r_type == PPC_RELOC_HI16)
4170 ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
4172 else if(scat->r_type == PPC_RELOC_HA16_SECTDIFF || scat->r_type == PPC_RELOC_HA16)
4174 ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
4175 + ((word & (1<<15)) ? 1 : 0);
4181 continue; // FIXME: I hope it's OK to ignore all the others.
4185 struct relocation_info *reloc = &relocs[i];
4186 if(reloc->r_pcrel && !reloc->r_extern)
4189 if(reloc->r_length == 2)
4191 unsigned long word = 0;
4192 #ifdef powerpc_HOST_ARCH
4193 unsigned long jumpIsland = 0;
4194 long offsetToJumpIsland = 0xBADBAD42; // initialise to bad value
4195 // to avoid warning and to catch
4199 unsigned long* wordPtr = (unsigned long*) (image + sect->offset + reloc->r_address);
4200 checkProddableBlock(oc,wordPtr);
4202 if(reloc->r_type == GENERIC_RELOC_VANILLA)
4206 #ifdef powerpc_HOST_ARCH
4207 else if(reloc->r_type == PPC_RELOC_LO16)
4209 word = ((unsigned short*) wordPtr)[1];
4210 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4212 else if(reloc->r_type == PPC_RELOC_HI16)
4214 word = ((unsigned short*) wordPtr)[1] << 16;
4215 word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
4217 else if(reloc->r_type == PPC_RELOC_HA16)
4219 word = ((unsigned short*) wordPtr)[1] << 16;
4220 word += ((short)relocs[i+1].r_address & (short)0xFFFF);
4222 else if(reloc->r_type == PPC_RELOC_BR24)
4225 word = (word & 0x03FFFFFC) | ((word & 0x02000000) ? 0xFC000000 : 0);
4229 if(!reloc->r_extern)
4232 sections[reloc->r_symbolnum-1].offset
4233 - sections[reloc->r_symbolnum-1].addr
4240 struct nlist *symbol = &nlist[reloc->r_symbolnum];
4241 char *nm = image + symLC->stroff + symbol->n_un.n_strx;
4242 void *symbolAddress = lookupSymbol(nm);
4245 errorBelch("\nunknown symbol `%s'", nm);
4251 #ifdef powerpc_HOST_ARCH
4252 // In the .o file, this should be a relative jump to NULL
4253 // and we'll change it to a relative jump to the symbol
4254 ASSERT(word + reloc->r_address == 0);
4255 jumpIsland = (unsigned long)
4256 &makeSymbolExtra(oc,
4258 (unsigned long) symbolAddress)
4262 offsetToJumpIsland = word + jumpIsland
4263 - (((long)image) + sect->offset - sect->addr);
4266 word += (unsigned long) symbolAddress
4267 - (((long)image) + sect->offset - sect->addr);
4271 word += (unsigned long) symbolAddress;
4275 if(reloc->r_type == GENERIC_RELOC_VANILLA)
4280 #ifdef powerpc_HOST_ARCH
4281 else if(reloc->r_type == PPC_RELOC_LO16)
4283 ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
4286 else if(reloc->r_type == PPC_RELOC_HI16)
4288 ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
4291 else if(reloc->r_type == PPC_RELOC_HA16)
4293 ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
4294 + ((word & (1<<15)) ? 1 : 0);
4297 else if(reloc->r_type == PPC_RELOC_BR24)
4299 if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
4301 // The branch offset is too large.
4302 // Therefore, we try to use a jump island.
4305 barf("unconditional relative branch out of range: "
4306 "no jump island available");
4309 word = offsetToJumpIsland;
4310 if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
4311 barf("unconditional relative branch out of range: "
4312 "jump island out of range");
4314 *wordPtr = (*wordPtr & 0xFC000003) | (word & 0x03FFFFFC);
4319 barf("\nunknown relocation %d",reloc->r_type);
4327 static int ocGetNames_MachO(ObjectCode* oc)
4329 char *image = (char*) oc->image;
4330 struct mach_header *header = (struct mach_header*) image;
4331 struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
4332 unsigned i,curSymbol = 0;
4333 struct segment_command *segLC = NULL;
4334 struct section *sections;
4335 struct symtab_command *symLC = NULL;
4336 struct nlist *nlist;
4337 unsigned long commonSize = 0;
4338 char *commonStorage = NULL;
4339 unsigned long commonCounter;
4341 for(i=0;i<header->ncmds;i++)
4343 if(lc->cmd == LC_SEGMENT || lc->cmd == LC_SEGMENT_64)
4344 segLC = (struct segment_command*) lc;
4345 else if(lc->cmd == LC_SYMTAB)
4346 symLC = (struct symtab_command*) lc;
4347 lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
4350 sections = (struct section*) (segLC+1);
4351 nlist = symLC ? (struct nlist*) (image + symLC->symoff)
4355 barf("ocGetNames_MachO: no segment load command");
4357 for(i=0;i<segLC->nsects;i++)
4359 if(sections[i].size == 0)
4362 if((sections[i].flags & SECTION_TYPE) == S_ZEROFILL)
4364 char * zeroFillArea = stgCallocBytes(1,sections[i].size,
4365 "ocGetNames_MachO(common symbols)");
4366 sections[i].offset = zeroFillArea - image;
4369 if(!strcmp(sections[i].sectname,"__text"))
4370 addSection(oc, SECTIONKIND_CODE_OR_RODATA,
4371 (void*) (image + sections[i].offset),
4372 (void*) (image + sections[i].offset + sections[i].size));
4373 else if(!strcmp(sections[i].sectname,"__const"))
4374 addSection(oc, SECTIONKIND_RWDATA,
4375 (void*) (image + sections[i].offset),
4376 (void*) (image + sections[i].offset + sections[i].size));
4377 else if(!strcmp(sections[i].sectname,"__data"))
4378 addSection(oc, SECTIONKIND_RWDATA,
4379 (void*) (image + sections[i].offset),
4380 (void*) (image + sections[i].offset + sections[i].size));
4381 else if(!strcmp(sections[i].sectname,"__bss")
4382 || !strcmp(sections[i].sectname,"__common"))
4383 addSection(oc, SECTIONKIND_RWDATA,
4384 (void*) (image + sections[i].offset),
4385 (void*) (image + sections[i].offset + sections[i].size));
4387 addProddableBlock(oc, (void*) (image + sections[i].offset),
4391 // count external symbols defined here
4395 for(i=0;i<symLC->nsyms;i++)
4397 if(nlist[i].n_type & N_STAB)
4399 else if(nlist[i].n_type & N_EXT)
4401 if((nlist[i].n_type & N_TYPE) == N_UNDF
4402 && (nlist[i].n_value != 0))
4404 commonSize += nlist[i].n_value;
4407 else if((nlist[i].n_type & N_TYPE) == N_SECT)
4412 oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
4413 "ocGetNames_MachO(oc->symbols)");
4417 for(i=0;i<symLC->nsyms;i++)
4419 if(nlist[i].n_type & N_STAB)
4421 else if((nlist[i].n_type & N_TYPE) == N_SECT)
4423 if(nlist[i].n_type & N_EXT)
4425 char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
4426 if((nlist[i].n_desc & N_WEAK_DEF) && lookupSymbol(nm))
4427 ; // weak definition, and we already have a definition
4430 ghciInsertStrHashTable(oc->fileName, symhash, nm,
4432 + sections[nlist[i].n_sect-1].offset
4433 - sections[nlist[i].n_sect-1].addr
4434 + nlist[i].n_value);
4435 oc->symbols[curSymbol++] = nm;
4442 commonStorage = stgCallocBytes(1,commonSize,"ocGetNames_MachO(common symbols)");
4443 commonCounter = (unsigned long)commonStorage;
4446 for(i=0;i<symLC->nsyms;i++)
4448 if((nlist[i].n_type & N_TYPE) == N_UNDF
4449 && (nlist[i].n_type & N_EXT) && (nlist[i].n_value != 0))
4451 char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
4452 unsigned long sz = nlist[i].n_value;
4454 nlist[i].n_value = commonCounter;
4456 ghciInsertStrHashTable(oc->fileName, symhash, nm,
4457 (void*)commonCounter);
4458 oc->symbols[curSymbol++] = nm;
4460 commonCounter += sz;
4467 static int ocResolve_MachO(ObjectCode* oc)
4469 char *image = (char*) oc->image;
4470 struct mach_header *header = (struct mach_header*) image;
4471 struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
4473 struct segment_command *segLC = NULL;
4474 struct section *sections;
4475 struct symtab_command *symLC = NULL;
4476 struct dysymtab_command *dsymLC = NULL;
4477 struct nlist *nlist;
4479 for(i=0;i<header->ncmds;i++)
4481 if(lc->cmd == LC_SEGMENT || lc->cmd == LC_SEGMENT_64)
4482 segLC = (struct segment_command*) lc;
4483 else if(lc->cmd == LC_SYMTAB)
4484 symLC = (struct symtab_command*) lc;
4485 else if(lc->cmd == LC_DYSYMTAB)
4486 dsymLC = (struct dysymtab_command*) lc;
4487 lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
4490 sections = (struct section*) (segLC+1);
4491 nlist = symLC ? (struct nlist*) (image + symLC->symoff)
4496 unsigned long *indirectSyms
4497 = (unsigned long*) (image + dsymLC->indirectsymoff);
4499 for(i=0;i<segLC->nsects;i++)
4501 if( !strcmp(sections[i].sectname,"__la_symbol_ptr")
4502 || !strcmp(sections[i].sectname,"__la_sym_ptr2")
4503 || !strcmp(sections[i].sectname,"__la_sym_ptr3"))
4505 if(!resolveImports(oc,image,symLC,§ions[i],indirectSyms,nlist))
4508 else if(!strcmp(sections[i].sectname,"__nl_symbol_ptr")
4509 || !strcmp(sections[i].sectname,"__pointers"))
4511 if(!resolveImports(oc,image,symLC,§ions[i],indirectSyms,nlist))
4514 else if(!strcmp(sections[i].sectname,"__jump_table"))
4516 if(!resolveImports(oc,image,symLC,§ions[i],indirectSyms,nlist))
4522 for(i=0;i<segLC->nsects;i++)
4524 if(!relocateSection(oc,image,symLC,nlist,segLC->nsects,sections,§ions[i]))
4528 #if defined (powerpc_HOST_ARCH)
4529 ocFlushInstructionCache( oc );
4535 #ifdef powerpc_HOST_ARCH
4537 * The Mach-O object format uses leading underscores. But not everywhere.
4538 * There is a small number of runtime support functions defined in
4539 * libcc_dynamic.a whose name does not have a leading underscore.
4540 * As a consequence, we can't get their address from C code.
4541 * We have to use inline assembler just to take the address of a function.
4545 static void machoInitSymbolsWithoutUnderscore()
4547 extern void* symbolsWithoutUnderscore[];
4548 void **p = symbolsWithoutUnderscore;
4549 __asm__ volatile(".globl _symbolsWithoutUnderscore\n.data\n_symbolsWithoutUnderscore:");
4553 __asm__ volatile(".long " # x);
4555 RTS_MACHO_NOUNDERLINE_SYMBOLS
4557 __asm__ volatile(".text");
4561 ghciInsertStrHashTable("(GHCi built-in symbols)", symhash, #x, *p++);
4563 RTS_MACHO_NOUNDERLINE_SYMBOLS
4570 * Figure out by how much to shift the entire Mach-O file in memory
4571 * when loading so that its single segment ends up 16-byte-aligned
4573 static int machoGetMisalignment( FILE * f )
4575 struct mach_header header;
4578 fread(&header, sizeof(header), 1, f);
4581 #if x86_64_TARGET_ARCH || powerpc64_TARGET_ARCH
4582 if(header.magic != MH_MAGIC_64)
4585 if(header.magic != MH_MAGIC)
4589 misalignment = (header.sizeofcmds + sizeof(header))
4592 return misalignment ? (16 - misalignment) : 0;