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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/>. */
/* Exercise unwinding AArch64's SVE registers from a signal frame. */
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <sys/prctl.h>
#include <unistd.h>
static int second_vl = 0;
static void
initialize_sve_state_main ()
{
__asm __volatile ("dup z0.b, -1");
__asm __volatile ("dup z1.b, -1");
__asm __volatile ("dup z2.b, -1");
__asm __volatile ("dup z3.b, -1");
__asm __volatile ("dup z4.b, -1");
__asm __volatile ("dup z5.b, -1");
__asm __volatile ("dup z6.b, -1");
__asm __volatile ("dup z7.b, -1");
__asm __volatile ("dup z8.b, -1");
__asm __volatile ("dup z9.b, -1");
__asm __volatile ("dup z10.b, -1");
__asm __volatile ("dup z11.b, -1");
__asm __volatile ("dup z12.b, -1");
__asm __volatile ("dup z13.b, -1");
__asm __volatile ("dup z14.b, -1");
__asm __volatile ("dup z15.b, -1");
__asm __volatile ("dup z16.b, -1");
__asm __volatile ("dup z17.b, -1");
__asm __volatile ("dup z18.b, -1");
__asm __volatile ("dup z19.b, -1");
__asm __volatile ("dup z20.b, -1");
__asm __volatile ("dup z21.b, -1");
__asm __volatile ("dup z22.b, -1");
__asm __volatile ("dup z23.b, -1");
__asm __volatile ("dup z24.b, -1");
__asm __volatile ("dup z25.b, -1");
__asm __volatile ("dup z26.b, -1");
__asm __volatile ("dup z27.b, -1");
__asm __volatile ("dup z28.b, -1");
__asm __volatile ("dup z29.b, -1");
__asm __volatile ("dup z30.b, -1");
__asm __volatile ("dup z31.b, -1");
__asm __volatile ("ptrue p0.d");
__asm __volatile ("ptrue p1.d");
__asm __volatile ("ptrue p2.d");
__asm __volatile ("ptrue p3.d");
__asm __volatile ("ptrue p4.d");
__asm __volatile ("ptrue p5.d");
__asm __volatile ("ptrue p6.d");
__asm __volatile ("ptrue p7.d");
__asm __volatile ("ptrue p8.d");
__asm __volatile ("ptrue p9.d");
__asm __volatile ("ptrue p10.d");
__asm __volatile ("ptrue p11.d");
__asm __volatile ("ptrue p12.d");
__asm __volatile ("ptrue p13.d");
__asm __volatile ("ptrue p14.d");
__asm __volatile ("ptrue p15.d");
__asm __volatile ("setffr");
}
static void
initialize_sve_state_sighandler ()
{
__asm __volatile ("dup z0.b, -2");
__asm __volatile ("dup z1.b, -2");
__asm __volatile ("dup z2.b, -2");
__asm __volatile ("dup z3.b, -2");
__asm __volatile ("dup z4.b, -2");
__asm __volatile ("dup z5.b, -2");
__asm __volatile ("dup z6.b, -2");
__asm __volatile ("dup z7.b, -2");
__asm __volatile ("dup z8.b, -2");
__asm __volatile ("dup z9.b, -2");
__asm __volatile ("dup z10.b, -2");
__asm __volatile ("dup z11.b, -2");
__asm __volatile ("dup z12.b, -2");
__asm __volatile ("dup z13.b, -2");
__asm __volatile ("dup z14.b, -2");
__asm __volatile ("dup z15.b, -2");
__asm __volatile ("dup z16.b, -2");
__asm __volatile ("dup z17.b, -2");
__asm __volatile ("dup z18.b, -2");
__asm __volatile ("dup z19.b, -2");
__asm __volatile ("dup z20.b, -2");
__asm __volatile ("dup z21.b, -2");
__asm __volatile ("dup z22.b, -2");
__asm __volatile ("dup z23.b, -2");
__asm __volatile ("dup z24.b, -2");
__asm __volatile ("dup z25.b, -2");
__asm __volatile ("dup z26.b, -2");
__asm __volatile ("dup z27.b, -2");
__asm __volatile ("dup z28.b, -2");
__asm __volatile ("dup z29.b, -2");
__asm __volatile ("dup z30.b, -2");
__asm __volatile ("dup z31.b, -2");
__asm __volatile ("pfalse p0.b");
__asm __volatile ("pfalse p1.b");
__asm __volatile ("pfalse p2.b");
__asm __volatile ("pfalse p3.b");
__asm __volatile ("pfalse p4.b");
__asm __volatile ("pfalse p5.b");
__asm __volatile ("pfalse p6.b");
__asm __volatile ("pfalse p7.b");
__asm __volatile ("pfalse p8.b");
__asm __volatile ("pfalse p9.b");
__asm __volatile ("pfalse p10.b");
__asm __volatile ("pfalse p11.b");
__asm __volatile ("pfalse p12.b");
__asm __volatile ("pfalse p13.b");
__asm __volatile ("pfalse p14.b");
__asm __volatile ("pfalse p15.b");
__asm __volatile ("setffr");
}
/* Set new value for the SVE vector length.
Return the value that was set. */
static int
set_vl (int vl)
{
int rc;
rc = prctl (PR_SVE_SET_VL, vl, 0, 0, 0);
if (rc < 0)
{
perror ("FAILED to PR_SVE_SET_VL");
exit (EXIT_FAILURE);
}
return rc & PR_SVE_VL_LEN_MASK;
}
static void
sighandler (int sig, siginfo_t *info, void *ucontext)
{
/* Set vector length to the second value. */
second_vl = set_vl (second_vl);
initialize_sve_state_sighandler ();
printf ("sighandler: second_vl = %d\n", second_vl); /* Break here. */
}
int
main (int argc, char *argv[])
{
if (argc != 3)
{
fprintf (stderr, "Usage: %s <first vl> <second vl>\n", argv[0]);
return 1;
}
int first_vl = atoi (argv[1]);
second_vl = atoi (argv[2]);
if (first_vl == 0 || second_vl == 0)
{
fprintf (stderr, "Invalid vector length.\n");
return 1;
}
/* Set vector length to the first value. */
first_vl = set_vl (first_vl);
printf ("main: first_vl = %d\n", first_vl);
unsigned char buf[256];
/* Use an SVE register to make the kernel start saving the SVE bank. */
asm volatile ("mov z0.b, #255\n\t"
"str z0, %0"
:
: "m" (buf)
: "z0", "memory");
initialize_sve_state_main ();
struct sigaction sigact;
sigact.sa_sigaction = sighandler;
sigact.sa_flags = SA_SIGINFO;
sigaction (SIGUSR1, &sigact, NULL);
kill (getpid (), SIGUSR1);
return 0;
}
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