checkasm: disable unaligned access emulation

The OS may silently fix (emulate) unaligned hardware access exceptions.
This is extremely slow and code should be fixed not to rely on unaligned
access on affected hardware. Accordingly this requests that the OS
disable emulation and instead throw Bus error, which will be caught by
checkasm's signal handler.

This has no effects if the hardware supports unaligned access in
hardware, since no exceptions are generated. prctl() will fail safe in
that case.

Signed-off-by: Paul B Mahol <onemda@gmail.com>
This commit is contained in:
Rémi Denis-Courmont 2024-06-01 10:55:51 +03:00 committed by Paul B Mahol
parent 71f91d9dd4
commit d2583e57f1

View File

@ -41,6 +41,9 @@
#if HAVE_IO_H
#include <io.h>
#endif
#if HAVE_PRCTL
#include <sys/prctl.h>
#endif
#if defined(_WIN32) && !defined(SIGBUS)
/* non-standard, use the same value as mingw-w64 */
@ -847,6 +850,9 @@ int main(int argc, char *argv[])
sigaction(SIGILL, &signal_handler_act, NULL);
sigaction(SIGSEGV, &signal_handler_act, NULL);
#endif
#if HAVE_PRCTL && defined(PR_SET_UNALIGN)
prctl(PR_SET_UNALIGN, PR_UNALIGN_SIGBUS);
#endif
#if ARCH_ARM && HAVE_ARMV5TE_EXTERNAL
if (have_vfp(av_get_cpu_flags()) || have_neon(av_get_cpu_flags()))
checkasm_checked_call = checkasm_checked_call_vfp;