src/libs/libunwind/tilegx/Gis_signal_frame.c

   1 /* libunwind - a platform-independent unwind library
   2    Copyright (C) 2008 CodeSourcery
   3    Copyright (C) 2014 Tilera Corp.
   4
   5 This file is part of libunwind.
   6
   7 Permission is hereby granted, free of charge, to any person obtaining
   8 a copy of this software and associated documentation files (the
   9 "Software"), to deal in the Software without restriction, including
  10 without limitation the rights to use, copy, modify, merge, publish,
  11 distribute, sublicense, and/or sell copies of the Software, and to
  12 permit persons to whom the Software is furnished to do so, subject to
  13 the following conditions:
  14
  15 The above copyright notice and this permission notice shall be
  16 included in all copies or substantial portions of the Software.
  17
  18 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  19 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  21 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  22 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  23 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  24 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
  25
  26 #include "unwind_i.h"
  27 #include <stdio.h>
  28 #include "offsets.h"
  29
  30 #ifdef __linux__
  31 #include <sys/syscall.h>
  32 #include <arch/abi.h>
  33 #else
  34 # error "Only support Linux!"
  35 #endif
  36
  37 #define  MOVELI_R10_RT_SIGRETURN                         \
  38   ( 0x000007e051483000ULL    |                           \
  39     ((unsigned long)__NR_rt_sigreturn << 43) |           \
  40     ((unsigned long)TREG_SYSCALL_NR << 31) )
  41 #define  SWINT1      0x286b180051485000ULL
  42
  43 PROTECTED int
  44 unw_is_signal_frame (unw_cursor_t *cursor)
  45 {
  46   struct cursor *c = (struct cursor*) cursor;
  47   unw_word_t w0, w1, ip;
  48   unw_addr_space_t as;
  49   unw_accessors_t *a;
  50   void *arg;
  51   int ret;
  52
  53   as = c->dwarf.as;
  54   a = unw_get_accessors (as);
  55   arg = c->dwarf.as_arg;
  56
  57   ip = c->dwarf.ip;
  58
  59   if (!ip || !a->access_mem || (ip & (sizeof(unw_word_t) - 1)))
  60     return 0;
  61
  62   if ((ret = (*a->access_mem) (as, ip, &w0, 0, arg)) < 0)
  63     return ret;
  64
  65   if ((ret = (*a->access_mem) (as, ip + 8, &w1, 0, arg)) < 0)
  66     return ret;
  67
  68   /* Return 1 if the IP points to a RT sigreturn sequence. */
  69   if (w0 == MOVELI_R10_RT_SIGRETURN &&
  70       w1 ==  SWINT1)
  71     {
  72       return 1;
  73     }
  74   return 0;
  75 }
  76
  77
  78 PROTECTED int
  79 unw_handle_signal_frame (unw_cursor_t *cursor)
  80 {
  81   int i;
  82   struct cursor *c = (struct cursor *) cursor;
  83   unw_word_t sc_addr, sp, sp_addr = c->dwarf.cfa;
  84   struct dwarf_loc sp_loc = DWARF_LOC (sp_addr, 0);
  85   int ret;
  86
  87   if ((ret = dwarf_get (&c->dwarf, sp_loc, &sp)) < 0)
  88     return -UNW_EUNSPEC;
  89
  90   /* Save the SP and PC to be able to return execution at this point
  91      later in time (unw_resume).  */
  92   c->sigcontext_sp = c->dwarf.cfa;
  93   c->sigcontext_pc = c->dwarf.ip;
  94
  95   c->sigcontext_addr = sp_addr + sizeof (siginfo_t) +
  96     C_ABI_SAVE_AREA_SIZE;
  97   sc_addr = c->sigcontext_addr + LINUX_UC_MCONTEXT_OFF;
  98
  99   /* Update the dwarf cursor.
 100      Set the location of the registers to the corresponding addresses of the
 101      uc_mcontext / sigcontext structure contents.  */
 102
 103 #define  SC_REG_OFFSET(X)   (8 * X)
 104
 105   for (i = UNW_TILEGX_R0; i <= UNW_TILEGX_R55; i++)
 106     {
 107       c->dwarf.loc[i] = DWARF_LOC (sc_addr + SC_REG_OFFSET(i), 0);
 108     }
 109
 110   /* Set SP/CFA and PC/IP.  */
 111   dwarf_get (&c->dwarf, c->dwarf.loc[UNW_TILEGX_R54], &c->dwarf.cfa);
 112   dwarf_get (&c->dwarf, c->dwarf.loc[UNW_TILEGX_R55], &c->dwarf.ip);
 113
 114   return 1;
 115 }