1 files changed, 53 insertions, 0 deletions
diff --git a/contrib/compiler-rt/lib/scudo/scudo_crc32.cpp b/contrib/compiler-rt/lib/scudo/scudo_crc32.cpp
new file mode 100644
index 0000000..94c8c24
--- /dev/null
+++ b/contrib/compiler-rt/lib/scudo/scudo_crc32.cpp
@@ -0,0 +1,53 @@
+//===-- scudo_crc32.cpp -----------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// CRC32 function leveraging hardware specific instructions. This has to be
+/// kept separated to restrict the use of compiler specific flags to this file.
+///
+//===----------------------------------------------------------------------===//
+
+// 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__
+#  include <smmintrin.h>
+#  define CRC32_INTRINSIC FIRST_32_SECOND_64(_mm_crc32_u32, _mm_crc32_u64)
+# endif
+# ifdef __ARM_FEATURE_CRC32
+#  include <arm_acle.h>
+#  define CRC32_INTRINSIC FIRST_32_SECOND_64(__crc32cw, __crc32cd)
+# endif
+#endif  // defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
+
+namespace __scudo {
+
+#if defined(__SSE4_2__) || defined(__ARM_FEATURE_CRC32)
+INLINE 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