/* Test if SSE valus are correctly propagated into and out of a signal handler
and also check that the same applies for uninitialised values and their
origins. */
#include <assert.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/ucontext.h>
static siginfo_t si;
static ucontext_t uc;
/* x0 is always zero, but is visible to Valgrind as uninitialised. */
static upad128_t x0;
static upad128_t d0 = {0};
static void sighandler(int sig, siginfo_t *sip, ucontext_t *ucp)
{
si = *sip;
uc = *ucp;
ucp->uc_mcontext.fpregs.fp_reg_set.fpchip_state.xmm[0] = d0;
ucp->uc_mcontext.fpregs.fp_reg_set.fpchip_state.xmm[1] = x0;
}
int main(void)
{
struct sigaction sa;
pid_t pid;
upad128_t out[8];
upad128_t y0;
struct fpchip_state *fs = &uc.uc_mcontext.fpregs.fp_reg_set.fpchip_state;
/* Uninitialised, but we know px[0] is 0x0. */
upad128_t *px = malloc(sizeof(*px));
x0 = px[0];
/* Uninitialised, but we know py[0] is 0x0. */
upad128_t *py = malloc(sizeof(*py));
y0 = py[0];
sa.sa_handler = sighandler;
sa.sa_flags = SA_SIGINFO;
if (sigfillset(&sa.sa_mask)) {
perror("sigfillset");
return 1;
}
if (sigaction(SIGUSR1, &sa, NULL)) {
perror("sigaction");
return 1;
}
pid = getpid();
__asm__ __volatile__(
/* Set values in the SSE registers. */
"movups %[y0], %%xmm0\n"
"movups %[d0], %%xmm1\n"
"movups %[d0], %%xmm2\n"
"movups %[y0], %%xmm3\n"
"movups %[y0], %%xmm4\n"
"movups %[d0], %%xmm5\n"
"movups %[d0], %%xmm6\n"
"movups %[y0], %%xmm7\n"
/* Trigger the signal handler. */
"syscall\n"
"movups %%xmm0, 0x00 + %[out]\n"
"movups %%xmm1, 0x10 + %[out]\n"
"movups %%xmm2, 0x20 + %[out]\n"
"movups %%xmm3, 0x30 + %[out]\n"
"movups %%xmm4, 0x40 + %[out]\n"
"movups %%xmm5, 0x50 + %[out]\n"
"movups %%xmm6, 0x60 + %[out]\n"
"movups %%xmm7, 0x70 + %[out]\n"
: [out] "=m" (out[0])
: "a" (SYS_kill), "D" (pid), "S" (SIGUSR1), [y0] "m" (y0), [d0] "m" (d0)
: "rdx", "cc", "memory");
printf("Values in the signal handler:\n");
printf(" xmm1=%Lf, xmm2=%Lf, xmm5=%Lf, xmm6=%Lf\n",
fs->xmm[1]._q, fs->xmm[2]._q, fs->xmm[5]._q, fs->xmm[6]._q);
/* Check that fs->xmm[0], fs->xmm[3], fs->xmm[4] and fs->xmm[7] contain
uninitialised values (origin is py[0]). */
if (fs->xmm[0]._q || fs->xmm[3]._q || fs->xmm[4]._q || fs->xmm[7]._q)
assert(0);
printf("Values after the return from the signal handler:\n");
printf(" xmm0=%Lf, xmm2=%Lf, xmm5=%Lf, xmm6=%Lf\n",
out[0]._q, out[2]._q, out[5]._q, out[6]._q);
/* Check that out[1], out[3], out[4] and out[7] contain uninitialised
values (origin is px[0]). */
if (out[1]._q || out[3]._q || out[4]._q || out[7]._q)
assert(0);
return 0;
}