[Support] Remove unused xxHash64

Now that there are no more users of xxHash64, remove it.

Signed-off-by: Kees Cook <[email protected]>

Author: kees

llvm/include/llvm/Support/xxhash.h

@@ -44,9 +44,6 @@
 
 namespace llvm {
 
-LLVM_ABI uint64_t xxHash64(llvm::StringRef Data);
-LLVM_ABI uint64_t xxHash64(llvm::ArrayRef<uint8_t> Data);
-
 LLVM_ABI uint64_t xxh3_64bits(ArrayRef<uint8_t> data);
 inline uint64_t xxh3_64bits(StringRef data) {
   return xxh3_64bits(ArrayRef(data.bytes_begin(), data.size()));

llvm/lib/Support/xxhash.cpp

@@ -77,20 +77,6 @@ static const uint64_t PRIME64_3 = 1609587929392839161ULL;
 static const uint64_t PRIME64_4 = 9650029242287828579ULL;
 static const uint64_t PRIME64_5 = 2870177450012600261ULL;
 
-static uint64_t round(uint64_t Acc, uint64_t Input) {
-  Acc += Input * PRIME64_2;
-  Acc = rotl64(Acc, 31);
-  Acc *= PRIME64_1;
-  return Acc;
-}
-
-static uint64_t mergeRound(uint64_t Acc, uint64_t Val) {
-  Val = round(0, Val);
-  Acc ^= Val;
-  Acc = Acc * PRIME64_1 + PRIME64_4;
-  return Acc;
-}
-
 static uint64_t XXH64_avalanche(uint64_t hash) {
   hash ^= hash >> 33;
   hash *= PRIME64_2;
@@ -100,70 +86,6 @@ static uint64_t XXH64_avalanche(uint64_t hash) {
   return hash;
 }
 
-uint64_t llvm::xxHash64(StringRef Data) {
-  size_t Len = Data.size();
-  uint64_t Seed = 0;
-  const unsigned char *P = Data.bytes_begin();
-  const unsigned char *const BEnd = Data.bytes_end();
-  uint64_t H64;
-
-  if (Len >= 32) {
-    const unsigned char *const Limit = BEnd - 32;
-    uint64_t V1 = Seed + PRIME64_1 + PRIME64_2;
-    uint64_t V2 = Seed + PRIME64_2;
-    uint64_t V3 = Seed + 0;
-    uint64_t V4 = Seed - PRIME64_1;
-
-    do {
-      V1 = round(V1, endian::read64le(P));
-      P += 8;
-      V2 = round(V2, endian::read64le(P));
-      P += 8;
-      V3 = round(V3, endian::read64le(P));
-      P += 8;
-      V4 = round(V4, endian::read64le(P));
-      P += 8;
-    } while (P <= Limit);
-
-    H64 = rotl64(V1, 1) + rotl64(V2, 7) + rotl64(V3, 12) + rotl64(V4, 18);
-    H64 = mergeRound(H64, V1);
-    H64 = mergeRound(H64, V2);
-    H64 = mergeRound(H64, V3);
-    H64 = mergeRound(H64, V4);
-
-  } else {
-    H64 = Seed + PRIME64_5;
-  }
-
-  H64 += (uint64_t)Len;
-
-  while (reinterpret_cast<uintptr_t>(P) + 8 <=
-         reinterpret_cast<uintptr_t>(BEnd)) {
-    uint64_t const K1 = round(0, endian::read64le(P));
-    H64 ^= K1;
-    H64 = rotl64(H64, 27) * PRIME64_1 + PRIME64_4;
-    P += 8;
-  }
-
-  if (reinterpret_cast<uintptr_t>(P) + 4 <= reinterpret_cast<uintptr_t>(BEnd)) {
-    H64 ^= (uint64_t)(endian::read32le(P)) * PRIME64_1;
-    H64 = rotl64(H64, 23) * PRIME64_2 + PRIME64_3;
-    P += 4;
-  }
-
-  while (P < BEnd) {
-    H64 ^= (*P) * PRIME64_5;
-    H64 = rotl64(H64, 11) * PRIME64_1;
-    P++;
-  }
-
-  return XXH64_avalanche(H64);
-}
-
-uint64_t llvm::xxHash64(ArrayRef<uint8_t> Data) {
-  return xxHash64({(const char *)Data.data(), Data.size()});
-}
-
 constexpr size_t XXH3_SECRETSIZE_MIN = 136;
 constexpr size_t XXH_SECRET_DEFAULT_SIZE = 192;
 

llvm/unittests/Support/xxhashTest.cpp

@@ -31,14 +31,6 @@ static void fillTestBuffer(uint8_t *buffer, size_t len) {
   }
 }
 
-TEST(xxhashTest, Basic) {
-  EXPECT_EQ(0xef46db3751d8e999U, xxHash64(StringRef()));
-  EXPECT_EQ(0x33bf00a859c4ba3fU, xxHash64("foo"));
-  EXPECT_EQ(0x48a37c90ad27a659U, xxHash64("bar"));
-  EXPECT_EQ(0x69196c1b3af0bff9U,
-            xxHash64("0123456789abcdefghijklmnopqrstuvwxyz"));
-}
-
 TEST(xxhashTest, xxh3) {
   constexpr size_t size = 2243;
   uint8_t a[size];