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/* This testcase is part of GDB, the GNU debugger.
Copyright 2025 Free Software Foundation, Inc.
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/>. */
int __attribute__ ((noinline))
bar (int x)
{
return x + x;
}
/* This function should generate a prologue in shape of:
push %rbp
.cfi_def_cfa_offset 16
.cfi_offset %rbp, -16
mov %rsp, %rbp
.cfi_def_cfa_register %rbp
push %reg1
push %reg2
sub $XXX, %rsp
.cfi_offset %reg2, 32
.cfi_offset %reg1, 24
So to be able to unwind a register, GDB needs to skip prologue past
register pushes and stack allocation (to access .cfi directives). */
int __attribute__ ((noinline))
foo (int a, int b, int c, int d)
{
/* "volatile" alone isn't enough for clang to not optimize it out and
allocate space on the stack. */
volatile char s[256];
for (int i = 0; i < 256; i++)
s[i] = (char) (a + i);
a += bar (a) + bar (b) + bar (c) + bar (d);
return a;
}
int
main (int argc, char **argv)
{
volatile int a = foo (argc, argc + 1, argc + 2, argc * 2);
return a;
}
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