1  /* Provide the runtime infrastructure for the transactional memory lib.
       2     Copyright (C) 2011-2023 Free Software Foundation, Inc.
       3     Contributed by Iain Sandoe <iains@gcc.gnu.org>
       4  
       5     This file is part of GCC.
       6  
       7  GCC is free software; you can redistribute it and/or modify it under
       8  the terms of the GNU General Public License as published by the Free
       9  Software Foundation; either version 3, or (at your option) any later
      10  version.
      11  
      12  GCC is distributed in the hope that it will be useful, but WITHOUT ANY
      13  WARRANTY; without even the implied warranty of MERCHANTABILITY or
      14  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
      15  for more details.
      16  
      17  Under Section 7 of GPL version 3, you are granted additional
      18  permissions described in the GCC Runtime Library Exception, version
      19  3.1, as published by the Free Software Foundation.
      20  
      21  You should have received a copy of the GNU General Public License and
      22  a copy of the GCC Runtime Library Exception along with this program;
      23  see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
      24  <http://www.gnu.org/licenses/>.  */
      25  
      26  #include "tsystem.h"
      27  #include <stddef.h>
      28  #include <dlfcn.h>
      29  #include <mach-o/dyld.h>
      30  #include <mach-o/getsect.h>
      31  
      32  #ifdef __LP64__
      33  #define GET_DATA_TMCT(mh,size) \
      34    getsectdatafromheader_64 ((struct mach_header_64*) mh, \
      35  			    "__DATA", "__tm_clone_table", (uint64_t *)size)
      36  #else
      37  #define GET_DATA_TMCT(mh,size) \
      38    getsectdatafromheader (mh, "__DATA", "__tm_clone_table", (uint32_t *)size)
      39  #endif
      40  
      41  #define WEAK __attribute__((weak))
      42  
      43  extern void _ITM_registerTMCloneTable (void *, size_t) WEAK;
      44  extern void _ITM_deregisterTMCloneTable (void *) WEAK;
      45  
      46  #if defined(START) || defined(END)
      47  static inline void *getTMCloneTable (const void *f, size_t *tmct_siz)
      48  {
      49    char *tmct_fixed, *tmct = NULL;
      50    unsigned int i, img_count; 
      51    struct mach_header *mh;
      52    Dl_info info;
      53    
      54    if (! dladdr (f, &info) || info.dli_fbase == NULL)
      55      abort ();
      56    
      57    mh = (struct mach_header *) info.dli_fbase;
      58    tmct_fixed = GET_DATA_TMCT (mh, tmct_siz);
      59    *tmct_siz /= (sizeof (size_t) * 2);
      60    /* No tm_clone_table or no clones. */
      61    if (tmct_fixed == NULL || *tmct_siz == 0)
      62      return NULL; 
      63  
      64    img_count = _dyld_image_count();
      65    for (i = 0; i < img_count && tmct == NULL; i++)
      66      {
      67        if (mh == _dyld_get_image_header(i))
      68  	tmct = tmct_fixed + (unsigned long)_dyld_get_image_vmaddr_slide(i); 
      69      }
      70  
      71    return tmct;
      72  }
      73  #endif
      74  
      75  #ifdef START
      76  
      77  void __doTMRegistrations (void) __attribute__ ((constructor));
      78  
      79  void __doTMRegistrations (void)
      80  {
      81    size_t tmct_siz;
      82    void *tmct;
      83  
      84    tmct = getTMCloneTable ((const void *)&__doTMRegistrations, &tmct_siz);
      85    if (_ITM_registerTMCloneTable != NULL && tmct != NULL)
      86      _ITM_registerTMCloneTable (tmct, (size_t)tmct_siz);
      87  }
      88  
      89  #endif
      90  
      91  #ifdef END
      92  
      93  void __doTMdeRegistrations (void) __attribute__ ((destructor));
      94  
      95  void __doTMdeRegistrations (void)
      96  {
      97    size_t tmct_siz;
      98    void *tmct;
      99  
     100    tmct = getTMCloneTable ((const void *)&__doTMdeRegistrations, &tmct_siz);
     101    if (_ITM_deregisterTMCloneTable != NULL && tmct != NULL)
     102      _ITM_deregisterTMCloneTable (tmct);
     103  }
     104  
     105  #endif