tests/tcg/s390x/branch-relative-long.c

   1 #include <stddef.h>
   2 #include <stdio.h>
   3 #include <string.h>
   4 #include <sys/mman.h>
   5
   6 #define DEFINE_ASM(_name, _code) \
   7     extern const char _name[]; \
   8     extern const char _name ## _end[]; \
   9     asm("    .globl " #_name "\n" \
  10         #_name ":\n" \
  11         "    " _code "\n" \
  12         "    .globl " #_name "_end\n" \
  13         #_name "_end:\n");
  14
  15 DEFINE_ASM(br_r14, "br %r14");
  16 DEFINE_ASM(brasl_r0, "brasl %r0,-0x100000000");
  17 DEFINE_ASM(brcl_0xf, "brcl 0xf,-0x100000000");
  18
  19 struct test {
  20     const char *code;
  21     const char *code_end;
  22 };
  23
  24 static const struct test tests[] = {
  25     {
  26         .code = brasl_r0,
  27         .code_end = brasl_r0_end,
  28     },
  29     {
  30         .code = brcl_0xf,
  31         .code_end = brcl_0xf_end,
  32     },
  33 };
  34
  35 int main(void)
  36 {
  37     unsigned char *buf;
  38     size_t length = 0;
  39     size_t i;
  40
  41     for (i = 0; i < sizeof(tests) / sizeof(tests[0]); i++) {
  42         size_t test_length = 0x100000000 + (tests[i].code_end - tests[i].code);
  43
  44         if (test_length > length) {
  45             length = test_length;
  46         }
  47     }
  48
  49     buf = mmap(NULL, length, PROT_READ | PROT_WRITE | PROT_EXEC,
  50                MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE, -1, 0);
  51     if (buf == MAP_FAILED) {
  52         perror("SKIP: mmap() failed");
  53         return 0;
  54     }
  55
  56     memcpy(buf, br_r14, br_r14_end - br_r14);
  57     for (i = 0; i < sizeof(tests) / sizeof(tests[0]); i++) {
  58         void (*code)(void) = (void *)(buf + 0x100000000);
  59
  60         memcpy(code, tests[i].code, tests[i].code_end - tests[i].code);
  61         code();
  62         memset(code, 0, tests[i].code_end - tests[i].code);
  63     }
  64
  65     munmap(buf, length);
  66
  67     return 0;
  68 }