1 // RUN: %clangxx_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
2 
3 // UNSUPPORTED: ios
4 
5 #include "test.h"
6 #include <sys/mman.h>
7 
8 // Test for previously unbounded memory consumption for large mallocs.
9 // Code allocates a large memory block (that is handled by LargeMmapAllocator),
10 // and forces allocation of meta shadow for the block. Then freed the block.
11 // But meta shadow was not unmapped. Then code occupies the virtual memory
12 // range of the block with something else (that does not need meta shadow).
13 // And repeats. As the result meta shadow growed infinitely.
14 // This program used to consume >2GB. Now it consumes <50MB.
15 
16 int main() {
17   for (int i = 0; i < 1000; i++) {
18     const int kSize = 1 << 20;
19     const int kPageSize = 4 << 10;
20     volatile int *p = new int[kSize];
21     for (int j = 0; j < kSize; j += kPageSize / sizeof(*p))
22       __atomic_store_n(&p[i], 1, __ATOMIC_RELEASE);
23     delete[] p;
24     mmap(0, kSize * sizeof(*p) + kPageSize, PROT_NONE, MAP_PRIVATE | MAP_ANON,
25         -1, 0);
26   }
27   fprintf(stderr, "DONE\n");
28   return 0;
29 }
30 
31 // CHECK: DONE
32