Index: lib/scudo/scudo_allocator.cpp
===================================================================
--- lib/scudo/scudo_allocator.cpp
+++ lib/scudo/scudo_allocator.cpp
@@ -15,7 +15,6 @@
 //===----------------------------------------------------------------------===//
 
 #include "scudo_allocator.h"
-#include "scudo_crc32.h"
 #include "scudo_utils.h"
 
 #include "sanitizer_common/sanitizer_allocator_interface.h"
@@ -73,15 +72,20 @@
 // at compilation or at runtime.
 static atomic_uint8_t HashAlgorithm = { CRC32Software };
 
-// Helper function that will compute the chunk checksum, being passed all the
-// the needed information as uptrs. It will opt for the hardware version of
-// the checksumming function if available.
-INLINE u32 hashUptrs(uptr Pointer, uptr *Array, uptr ArraySize, u8 HashType) {
-  u32 Crc;
-  Crc = computeCRC32(Cookie, Pointer, HashType);
-  for (uptr i = 0; i < ArraySize; i++)
-    Crc = computeCRC32(Crc, Array[i], HashType);
-  return Crc;
+SANITIZER_WEAK_ATTRIBUTE u32 computeHardwareCRC32(u32 Crc, uptr Data);
+
+INLINE u32 computeCRC32(u32 Crc, uptr Data, u8 HashType) {
+  // If SSE4.2 is defined here, it was enabled everywhere, as opposed to only
+  // for scudo_crc32.cpp. This means that other SSE instructions were likely
+  // emitted at other places, and as a result there is no reason to not use
+  // the hardware version of the CRC32.
+#if defined(__SSE4_2__)
+  return computeHardwareCRC32(Crc, Data);
+#else
+  if (computeHardwareCRC32 && HashType == CRC32Hardware)
+    return computeHardwareCRC32(Crc, Data);
+  return computeSoftwareCRC32(Crc, Data);
+#endif  // defined(__SSE4_2__)
 }
 
 struct ScudoChunk : UnpackedHeader {
@@ -108,11 +112,11 @@
     ZeroChecksumHeader.Checksum = 0;
     uptr HeaderHolder[sizeof(UnpackedHeader) / sizeof(uptr)];
     memcpy(&HeaderHolder, &ZeroChecksumHeader, sizeof(HeaderHolder));
-    u32 Hash = hashUptrs(reinterpret_cast<uptr>(this),
-                         HeaderHolder,
-                         ARRAY_SIZE(HeaderHolder),
-                         atomic_load_relaxed(&HashAlgorithm));
-    return static_cast<u16>(Hash);
+    u8 HashType = atomic_load_relaxed(&HashAlgorithm);
+    u32 Crc = computeCRC32(Cookie, reinterpret_cast<uptr>(this), HashType);
+    for (uptr i = 0; i < ARRAY_SIZE(HeaderHolder); i++)
+      Crc = computeCRC32(Crc, HeaderHolder[i], HashType);
+    return static_cast<u16>(Crc);
   }
 
   // Checks the validity of a chunk by verifying its checksum.
Index: lib/scudo/scudo_crc32.h
===================================================================
--- lib/scudo/scudo_crc32.h
+++ /dev/null
@@ -1,30 +0,0 @@
-//===-- scudo_crc32.h -------------------------------------------*- C++ -*-===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-///
-/// Header for scudo_crc32.cpp.
-///
-//===----------------------------------------------------------------------===//
-
-#ifndef SCUDO_CRC32_H_
-#define SCUDO_CRC32_H_
-
-#include "sanitizer_common/sanitizer_internal_defs.h"
-
-namespace __scudo {
-
-enum : u8 {
-  CRC32Software = 0,
-  CRC32Hardware = 1,
-};
-
-u32 computeCRC32(u32 Crc, uptr Data, u8 HashType);
-
-}  // namespace __scudo
-
-#endif  // SCUDO_CRC32_H_
Index: lib/scudo/scudo_crc32.cpp
===================================================================
--- lib/scudo/scudo_crc32.cpp
+++ lib/scudo/scudo_crc32.cpp
@@ -12,13 +12,13 @@
 ///
 //===----------------------------------------------------------------------===//
 
+#include "sanitizer_common/sanitizer_internal_defs.h"
+
 // Hardware CRC32 is supported at compilation via the following:
 // - for i386 & x86_64: -msse4.2
 // - for ARM & AArch64: -march=armv8-a+crc or -mcrc
 // An additional check must be performed at runtime as well to make sure the
 // emitted instructions are valid on the target host.
-#include "scudo_crc32.h"
-#include "scudo_utils.h"
 
 #if defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
 # ifdef __SSE4_2__
@@ -34,20 +34,9 @@
 namespace __scudo {
 
 #if defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
-INLINE u32 computeHardwareCRC32(u32 Crc, uptr Data) {
+u32 computeHardwareCRC32(u32 Crc, uptr Data) {
   return CRC32_INTRINSIC(Crc, Data);
 }
-
-u32 computeCRC32(u32 Crc, uptr Data, u8 HashType) {
-  if (HashType == CRC32Hardware) {
-    return computeHardwareCRC32(Crc, Data);
-  }
-  return computeSoftwareCRC32(Crc, Data);
-}
-#else
-u32 computeCRC32(u32 Crc, uptr Data, u8 HashType) {
-  return computeSoftwareCRC32(Crc, Data);
-}
 #endif  // defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
 
 }  // namespace __scudo
Index: lib/scudo/scudo_utils.h
===================================================================
--- lib/scudo/scudo_utils.h
+++ lib/scudo/scudo_utils.h
@@ -53,7 +53,11 @@
   u64 State[2];
 };
 
-// Software CRC32 functions, to be used when hardware support is not detected.
+enum : u8 {
+  CRC32Software = 0,
+  CRC32Hardware = 1,
+};
+
 u32 computeSoftwareCRC32(u32 Crc, uptr Data);
 
 }  // namespace __scudo
Index: lib/scudo/scudo_utils.cpp
===================================================================
--- lib/scudo/scudo_utils.cpp
+++ lib/scudo/scudo_utils.cpp
@@ -20,8 +20,9 @@
 #if defined(__x86_64__) || defined(__i386__)
 # include <cpuid.h>
 #endif
-
-#include <cstring>
+#if defined(__arm__) || defined(__aarch64__)
+# include <sys/auxv.h>
+#endif
 
 // TODO(kostyak): remove __sanitizer *Printf uses in favor for our own less
 //                complicated string formatting code. The following is a
@@ -97,6 +98,20 @@
   }
   return false;
 }
+#elif defined(__arm__) || defined(__aarch64__)
+// For ARM and AArch64, hardware CRC32 support is indicated in the
+// AT_HWVAL auxiliary vector.
+bool testCPUFeature(CPUFeature Feature) {
+  static uptr HWCap = getauxval(AT_HWCAP);
+
+  switch (Feature) {
+    case CRC32CPUFeature:
+      return !!(HWCap & HWCAP_CRC32);
+    default:
+      break;
+  }
+  return false;
+}
 #else
 bool testCPUFeature(CPUFeature Feature) {
   return false;