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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.
This commit is contained in:
Rémi Denis-Courmont 2024-06-01 10:55:51 +03:00
parent c3dbbb316e
commit 8d117024fe
1 changed files with 6 additions and 0 deletions
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6
tests/checkasm/checkasm.c
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;