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1// RUN: %clangxx_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s2 3// UNSUPPORTED: ios4 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 memory12// 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 16int 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: DONE32