tests/tcg/arm/pcalign-a32.c

   1 /* Test PC misalignment exception */
   2
   3 #ifdef __thumb__
   4 #error "This test must be compiled for ARM"
   5 #endif
   6
   7 #include <assert.h>
   8 #include <signal.h>
   9 #include <stdlib.h>
  10 #include <stdio.h>
  11
  12 static void *expected;
  13
  14 static void sigbus(int sig, siginfo_t *info, void *vuc)
  15 {
  16     assert(info->si_code == BUS_ADRALN);
  17     assert(info->si_addr == expected);
  18     exit(EXIT_SUCCESS);
  19 }
  20
  21 int main()
  22 {
  23     void *tmp;
  24
  25     struct sigaction sa = {
  26         .sa_sigaction = sigbus,
  27         .sa_flags = SA_SIGINFO
  28     };
  29
  30     if (sigaction(SIGBUS, &sa, NULL) < 0) {
  31         perror("sigaction");
  32         return EXIT_FAILURE;
  33     }
  34
  35     asm volatile("adr %0, 1f + 2\n\t"
  36                  "str %0, %1\n\t"
  37                  "bx  %0\n"
  38                  "1:"
  39                  : "=&r"(tmp), "=m"(expected));
  40
  41     /*
  42      * From v8, it is CONSTRAINED UNPREDICTABLE whether BXWritePC aligns
  43      * the address or not.  If so, we can legitimately fall through.
  44      */
  45     return EXIT_SUCCESS;
  46 }