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/* Unwinder test program.
Copyright 2006-2017 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);
void switch_stack_to_same (void);
void switch_stack_to_other (void);
int
main (void)
{
tpcs_frame ();
switch_stack_to_same ();
switch_stack_to_other ();
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"
);
asm(".text\n"
" .align 2\n"
" .thumb_func\n"
" .code 16\n"
"write_sp:\n"
" mov sp, r0\n"
" bx lr\n"
" .align 2\n"
" .thumb_func\n"
" .code 16\n"
"switch_stack_to_same:\n"
" push {lr}\n"
" mov r0, sp\n"
" bl write_sp\n"
" pop {r1}\n"
" bx r1\n"
" .align 2\n"
" .thumb_func\n"
" .code 16\n"
"switch_stack_to_other:\n"
" push {lr}\n"
" mov r7, sp\n"
" mov r0, #128\n"
" bl write_sp\n"
" mov sp, r7\n"
" pop {r1}\n"
" bx r1\n");
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