test/badCache.m

   1 /*
   2 TEST_CRASHES
   3 TEST_RUN_OUTPUT
   4 arm
   5 OK: badCache.m
   6 OR
   7 crash now
   8 objc\[\d+\]: Method cache corrupted.*
   9 objc\[\d+\]: .*
  10 objc\[\d+\]: .*
  11 objc\[\d+\]: .*
  12 objc\[\d+\]: .*
  13 objc\[\d+\]: Method cache corrupted.*
  14 objc\[\d+\]: HALTED
  15 END
  16 */
  17
  18
  19 #include "test.h"
  20
  21 // Test objc_msgSend's detection of infinite loops during cache scan.
  22
  23 #if __arm__
  24
  25 int main()
  26 {
  27     testwarn("objc_msgSend on arm doesn't detect infinite loops");
  28     fprintf(stderr, "arm\n");
  29     succeed(__FILE__);
  30 }
  31
  32 #else
  33
  34 #include "testroot.i"
  35
  36 #if __LP64__
  37 typedef uint32_t mask_t;
  38 #else
  39 typedef uint16_t mask_t;
  40 #endif
  41
  42 struct bucket_t {
  43     uintptr_t sel;
  44     uintptr_t imp;
  45 };
  46
  47 struct cache_t {
  48     uintptr_t buckets;
  49     mask_t mask;
  50     mask_t occupied;
  51 };
  52
  53 struct class_t {
  54     void *isa;
  55     void *supercls;
  56     struct cache_t cache;
  57 };
  58
  59 @interface Subclass : TestRoot @end
  60 @implementation Subclass @end
  61
  62 int main()
  63 {
  64     Class cls = [TestRoot class];
  65     id obj = [cls new];
  66     [obj self];
  67
  68     struct cache_t *cache = &((__bridge struct class_t *)cls)->cache;
  69
  70     // Figure out which cache mask scheme is in use by examining the existing bits.
  71     int low4 = 0;
  72 #if __LP64__
  73     int top16 = 0;
  74 #endif
  75     int outlined = 0;
  76
  77     if (cache->buckets & 0xf) {
  78         low4 = 1;
  79 #if __LP64__
  80     } else if ((cache->buckets & (0xffffULL << 48))) {
  81         top16 = 1;
  82 #endif
  83     } else {
  84         outlined = 1;
  85     }
  86
  87 #   define COUNT 4
  88 #   define COUNTSHIFT 14
  89     struct bucket_t *buckets = (struct bucket_t *)calloc(sizeof(struct bucket_t), COUNT+1);
  90     for (int i = 0; i < COUNT; i++) {
  91         buckets[i].sel = ~0;
  92         buckets[i].imp = ~0;
  93     }
  94     buckets[COUNT].sel = 1;
  95     buckets[COUNT].imp = (uintptr_t)buckets;
  96
  97     if (low4) {
  98         cache->buckets = (uintptr_t)buckets | COUNTSHIFT;
  99 #if __LP64__
 100     } else if (top16) {
 101         cache->buckets = ((uintptr_t)(COUNT - 1) << 48) | (uintptr_t)buckets;
 102 #endif
 103     } else if (outlined) {
 104         cache->mask = COUNT-1;
 105         cache->buckets = (uintptr_t)buckets;
 106     }
 107
 108     cache->occupied = 0;
 109
 110     fprintf(stderr, "crash now\n");
 111     [obj self];
 112
 113     fail("should have crashed");
 114 }
 115
 116 #endif