Changed: Unroll threshold for lower string hash

Reloaded-Project · Mar 12, 2024 · 35373ea · 35373ea
1 parent c7f9f88
commit 35373ea
Showing 1 changed file with 2 additions and 72 deletions.
diff --git a/src/Reloaded.Memory/Internals/Algorithms/UnstableStringHashLower.cs b/src/Reloaded.Memory/Internals/Algorithms/UnstableStringHashLower.cs
@@ -386,47 +386,8 @@ internal static unsafe UIntPtr UnstableHashNonVectorLower32(this ReadOnlySpan<ch
             // be ok because we expect this to be very rare in practice.
             const uint normalizeToLowercase = 0x0020_0020; // valid both for big-endian and for little-endian
 
-            // 32 byte
-            while (length >= (sizeof(uint) / sizeof(char)) * 8)
-            {
-                length -= (sizeof(uint) / sizeof(char)) * 8;
-
-                var p0 = ptr[0];
-                var p1 = ptr[1];
-                if (!AllCharsInUIntAreAscii(p0 | p1))
-                    goto NotAscii;
-
-                hash1 = (hash1 ^ (p0 | normalizeToLowercase)) * prime;
-                hash2 = (hash2 ^ (p1 | normalizeToLowercase)) * prime;
-
-                p0 = ptr[2];
-                p1 = ptr[3];
-                if (!AllCharsInUIntAreAscii(p0 | p1))
-                    goto NotAscii;
-
-                hash1 = (hash1 ^ (p0 | normalizeToLowercase)) * prime;
-                hash2 = (hash2 ^ (p1 | normalizeToLowercase)) * prime;
-
-                p0 = ptr[4];
-                p1 = ptr[5];
-                if (!AllCharsInUIntAreAscii(p0 | p1))
-                    goto NotAscii;
-
-                hash1 = (hash1 ^ (p0 | normalizeToLowercase)) * prime;
-                hash2 = (hash2 ^ (p1 | normalizeToLowercase)) * prime;
-
-                p0 = ptr[6];
-                p1 = ptr[7];
-                if (!AllCharsInUIntAreAscii(p0 | p1))
-                    goto NotAscii;
-
-                hash1 = (hash1 ^ (p0 | normalizeToLowercase)) * prime;
-                hash2 = (hash2 ^ (p1 | normalizeToLowercase)) * prime;
-                ptr += 8;
-            }
-
             // 16 byte
-            if (length >= (sizeof(uint) / sizeof(char)) * 4)
+            while (length >= (sizeof(uint) / sizeof(char)) * 4)
             {
                 length -= (sizeof(uint) / sizeof(char)) * 4;
 
@@ -506,39 +467,8 @@ internal static unsafe UIntPtr UnstableHashNonVectorLower64(this ReadOnlySpan<ch
             // be ok because we expect this to be very rare in practice.
             const ulong normalizeToLowercase = 0x0020_0020_0020_0020; // valid both for big-endian and for little-endian
 
-            // 64 byte
-            while (length >= (sizeof(ulong) / sizeof(char)) * 8)
-            {
-                length -= (sizeof(ulong) / sizeof(char)) * 8;
-
-                var p0 = ptr[0];
-                var p1 = ptr[1];
-                var p2 = ptr[2];
-                var p3 = ptr[3];
-                if (!AllCharsInULongAreAscii(p0 | p1 | p2 | p3))
-                    goto NotAscii;
-
-                hash1 = (hash1 ^ (p0 | normalizeToLowercase)) * prime;
-                hash2 = (hash2 ^ (p1 | normalizeToLowercase)) * prime;
-                hash1 = (hash1 ^ (p2 | normalizeToLowercase)) * prime;
-                hash2 = (hash2 ^ (p3 | normalizeToLowercase)) * prime;
-
-                p0 = ptr[4];
-                p1 = ptr[5];
-                p2 = ptr[6];
-                p3 = ptr[7];
-                if (!AllCharsInULongAreAscii(p0 | p1 | p2 | p3))
-                    goto NotAscii;
-
-                hash1 = (hash1 ^ (p0 | normalizeToLowercase)) * prime;
-                hash2 = (hash2 ^ (p1 | normalizeToLowercase)) * prime;
-                hash1 = (hash1 ^ (p2 | normalizeToLowercase)) * prime;
-                hash2 = (hash2 ^ (p3 | normalizeToLowercase)) * prime;
-                ptr += 8;
-            }
-
             // 32 byte
-            if (length >= (sizeof(ulong) / sizeof(char)) * 4)
+            while (length >= (sizeof(ulong) / sizeof(char)) * 4)
             {
                 length -= (sizeof(ulong) / sizeof(char)) * 4;