Subversion Repositories openrisc

/* Unwinder test program.

   Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

void tpcs_frame (void);

int

main (void)

{

  tpcs_frame ();

  return 0;

}

/* Normally Thumb functions use r7 as the frame pointer.  However,

   with the GCC option -mtpcs-frame, they may use fp instead.  Make

   sure that the prologue analyzer can handle this.  */

asm(".text\n"

    "   .align 2\n"

    "   .thumb_func\n"

    "   .code 16\n"

    "tpcs_frame_1:\n"

    "   sub     sp, #16\n"

    "   push    {r7}\n"

    "   add     r7, sp, #20\n"

    "   str     r7, [sp, #8]\n"

    "   mov     r7, pc\n"

    "   str     r7, [sp, #16]\n"

    "   mov     r7, fp\n"

    "   str     r7, [sp, #4]\n"

    "   mov     r7, lr\n"

    "   str     r7, [sp, #12]\n"

    "   add     r7, sp, #16\n"

    "   mov     fp, r7\n"

    "   mov     r7, sl\n"

    "   push    {r7}\n"

    /* We'll set a breakpoint at this call.  We can't hardcode a trap

       instruction; the right instruction to use varies too much.  And

       we can't use a global label, because GDB will think that's the

       start of a new function.  So, this slightly convoluted

       technique.  */

    ".Ltpcs:\n"

    "   nop\n"

    "   pop     {r2}\n"

    "   mov     sl, r2\n"

    "   pop     {r7}\n"

    "   pop     {r1, r2}\n"

    "   mov     fp, r1\n"

    "   mov     sp, r2\n"

    "   bx      lr\n"

    "   .align 2\n"

    "   .type tpcs_offset, %object\n"

    "tpcs_offset:\n"

    "   .word .Ltpcs - tpcs_frame_1\n"

    "   .align 2\n"

    "   .thumb_func\n"

    "   .code 16\n"

    "tpcs_frame:\n"

    "   sub     sp, #16\n"

    "   push    {r7}\n"

    "   add     r7, sp, #20\n"

    "   str     r7, [sp, #8]\n"

    "   mov     r7, pc\n"

    "   str     r7, [sp, #16]\n"

    "   mov     r7, fp\n"

    "   str     r7, [sp, #4]\n"

    "   mov     r7, lr\n"

    "   str     r7, [sp, #12]\n"

    "   add     r7, sp, #16\n"

    "   mov     fp, r7\n"

    "   mov     r7, sl\n"

    "   push    {r7}\n"

    /* Clobber saved regs around the call.  */

    "   mov     r7, #0\n"

    "   mov     lr, r7\n"

    "   bl      tpcs_frame_1\n"

    "   pop     {r2}\n"

    "   mov     sl, r2\n"

    "   pop     {r7}\n"

    "   pop     {r1, r2, r3}\n"

    "   mov     fp, r1\n"

    "   mov     sp, r2\n"

    "   mov     lr, r3\n"

    "   bx      lr\n"

);