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1#include <string.h>2#include <sys/system_properties.h>3 4static bool __isExynos9810(void) {5  char arch[PROP_VALUE_MAX];6  return __system_property_get("ro.arch", arch) > 0 &&7    strncmp(arch, "exynos9810", sizeof("exynos9810") - 1) == 0;8}9 10static void CONSTRUCTOR_ATTRIBUTE init_have_lse_atomics(void) {11  unsigned long hwcap = getauxval(AT_HWCAP);12  _Bool result = (hwcap & HWCAP_ATOMICS) != 0;13  if (result) {14    // Some cores in the Exynos 9810 CPU are ARMv8.2 and others are ARMv8.0;15    // only the former support LSE atomics.  However, the kernel in the16    // initial Android 8.0 release of Galaxy S9/S9+ devices incorrectly17    // reported the feature as being supported.18    //19    // The kernel appears to have been corrected to mark it unsupported as of20    // the Android 9.0 release on those devices, and this issue has not been21    // observed anywhere else. Thus, this workaround may be removed if22    // compiler-rt ever drops support for Android 8.0.23    if (__isExynos9810())24      result = false;25  }26  __aarch64_have_lse_atomics = result;27}28