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-rw-r--r--source/tanya/hash/lookup.d342
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diff --git a/source/tanya/hash/lookup.d b/source/tanya/hash/lookup.d
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--- a/source/tanya/hash/lookup.d
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@@ -1,342 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/**
- * Non-cryptographic, lookup hash functions.
- *
- * Copyright: Eugene Wissner 2018-2025.
- * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
- * Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
- * Source: $(LINK2 https://github.com/caraus-ecms/tanya/blob/master/source/tanya/hash/lookup.d,
- * tanya/hash/lookup.d)
- */
-module tanya.hash.lookup;
-
-import std.range : isInfinite, isInputRange;
-import std.traits;
-import tanya.meta;
-import tanya.range.primitive;
-
-private struct Hasher
-{
- static if (size_t.sizeof == 4)
- {
- enum uint offsetBasis = 2166136261;
- enum uint prime = 16777619;
- }
- else static if (size_t.sizeof == 8)
- {
- enum ulong offsetBasis = 14695981039346656037UL;
- enum ulong prime = 1099511628211UL;
- }
- else static if (size_t.sizeof == 16)
- {
- enum size_t offsetBasis = (size_t(0x6c62272e07bb0142UL) << 64) + 0x62b821756295c58dUL;
- enum size_t prime = (size_t(1) << 88) + (1 << 8) + 0x3b;
- }
- else
- {
- static assert(false, "FNV requires at least 32-bit hash length");
- }
-
- size_t hash = offsetBasis;
-
- void opCall(T)(auto ref T key)
- {
- static if (is(typeof(key.toHash()) == size_t))
- {
- opCall(key.toHash()); // Combine user-defined hashes
- }
- else static if (isScalarType!T || isPointer!T)
- {
- // Treat as an array of words
- static if (T.sizeof % size_t.sizeof == 0
- && T.alignof >= size_t.alignof)
- alias CastT = size_t;
- // (64-bit or 128-bit) Treat as an array of ints
- else static if (T.sizeof % uint.sizeof == 0
- && T.alignof >= uint.alignof)
- alias CastT = uint;
- // Treat as an array of bytes
- else
- alias CastT = ubyte;
- add((() @trusted => (cast(const CastT*) &key)[0 .. T.sizeof / CastT.sizeof])());
- }
- else static if (isArray!T && isScalarType!(ElementType!T))
- {
- // Treat as an array of words
- static if (ElementType!T.sizeof % size_t.sizeof == 0
- && ElementType!T.alignof >= size_t.alignof)
- alias CastT = size_t;
- // (64-bit or 128-bit) Treat as an array of ints
- else static if (ElementType!T.sizeof % uint.sizeof == 0
- && ElementType!T.alignof >= uint.alignof)
- alias CastT = uint;
- // Treat as an array of bytes
- else
- alias CastT = ubyte;
- add(cast(const CastT[]) key);
- }
- else static if (is(T == typeof(null)))
- {
- add(key);
- }
- else static if (isInputRange!T && !isInfinite!T)
- {
- foreach (e; key)
- {
- opCall(e);
- }
- }
- else
- {
- static assert(false, "Hash function is not available");
- }
- }
-
- void add(scope const ubyte[] key) @nogc nothrow pure @safe
- {
- // FNV-1a
- foreach (c; key)
- {
- this.hash = (this.hash ^ c) * prime;
- }
- }
-
- void add(scope const size_t[] key) @nogc nothrow pure @safe
- {
- static if (size_t.sizeof == 4)
- {
- // Partial MurmurHash3_x86_32 (no finalization)
- enum uint c1 = 0xcc9e2d51;
- enum uint c2 = 0x1b873593;
- alias h1 = hash;
- foreach (x; key)
- {
- auto k1 = x * c1;
- k1 = (k1 << 15) | (k1 >> (32 - 15));
- k1 *= c2;
-
- h1 ^= k1;
- h1 = (h1 << 13) | (h1 >> (32 - 13));
- h1 = h1 * 5 + 0xe6546b64;
- }
- }
- else static if (size_t.sizeof == 8)
- {
- // Partial 64-bit MurmurHash64A (no finalization)
- alias h = hash;
- enum ulong m = 0xc6a4a7935bd1e995UL;
- foreach (x; key)
- {
- auto k = x * m;
- k ^= k >>> 47;
- k *= m;
-
- h ^= k;
- h *= m;
- }
- }
- else static if (size_t.sizeof == 16)
- {
- // Partial MurmurHash3_x64_128 (no finalization)
- // treating each size_t as a pair of ulong.
- ulong h1 = cast(ulong) hash;
- ulong h2 = cast(ulong) (hash >> 64);
-
- enum ulong c1 = 0x87c37b91114253d5UL;
- enum ulong c2 = 0x4cf5ad432745937fUL;
-
- foreach (x; key)
- {
- auto k1 = cast(ulong) x;
- auto k2 = cast(ulong) (x >> 64);
-
- k1 *= c1; k1 = (k1 << 32) | (k1 >> (64 - 31)); k1 *= c2; h1 ^= k1;
- h1 = (h1 << 27) | (h1 >> (64 - 27)); h1 += h2; h1 = h1*5+0x52dce729;
- k2 *= c2; k2 = (k2 << 33) | (k2 >> (64 - 33)); k2 *= c1; h2 ^= k2;
- h2 = (h2 << 31) | (h2 >> (64 - 31)); h2 += h1; h2 = h2*5+0x38495ab5;
- }
-
- hash = cast(size_t) h1 + ((cast(size_t) h2) << 64);
- }
- else
- {
- static assert(0, "Hash length must be either 32, 64, or 128 bits.");
- }
- }
-
- static if (size_t.sizeof != uint.sizeof)
- void add(scope const uint[] key) @nogc nothrow pure @trusted
- {
- static if (size_t.sizeof == 8)
- {
- // Partial 32-bit MurmurHash64B (no finalization)
- enum uint m = 0x5bd1e995;
- enum r = 24;
-
- uint h1 = cast(uint) hash;
- uint h2 = cast(uint) (hash >> 32);
- const(uint)* data = key.ptr;
- auto len = key.length;
-
- for (; len >= 2; data += 2, len -= 2)
- {
- uint k1 = data[0];
- k1 *= m; k1 ^= k1 >> r; k1 *= m;
- h1 *= m; h1 ^= k1;
-
- uint k2 = data[1];
- k2 *= m; k2 ^= k2 >> r; k2 *= m;
- h2 *= m; h2 ^= k2;
- }
- if (len)
- {
- uint k1 = data[0];
- k1 *= m; k1 ^= k1 >> r; k1 *= m;
- h1 *= m; h1 ^= k1;
- }
- hash = cast(ulong) h1 + ((cast(ulong) h2) << 32);
- }
- else static if (size_t.sizeof == 16)
- {
- // Partial MurmurHash3_x86_128 (no finalization)
- enum uint c1 = 0x239b961b;
- enum uint c2 = 0xab0e9789;
- enum uint c3 = 0x38b34ae5;
- enum uint c4 = 0xa1e38b93;
-
- uint h1 = cast(uint) hash;
- uint h2 = cast(uint) (hash >> 32);
- uint h3 = cast(uint) (hash >> 64);
- uint h4 = cast(uint) (hash >> 96);
- const(uint)* data = key.ptr;
- auto len = key.length;
-
- for (; len >= 4; data += 4, len -= 4)
- {
- uint k1 = data[0];
- uint k2 = data[1];
- uint k3 = data[2];
- uint k4 = data[3];
-
- h1 = (h1 << 19) | (h1 >> (32 - 19)); h1 += h2; h1 = h1*5+0x561ccd1b;
- k2 *= c2; k2 = (k2 << 16) | (k2 >> (32 - 16)); k2 *= c3; h2 ^= k2;
- h2 = (h2 << 17) | (h2 >> (32 - 17)); h2 += h3; h2 = h2*5+0x0bcaa747;
- k3 *= c3; k3 = (k3 << 17) | (k3 >> (32 - 17)); k3 *= c4; h3 ^= k3;
- h3 = (h3 << 15) | (h3 >> (32 - 15)); h3 += h4; h3 = h3*5+0x96cd1c35;
- k4 *= c4; k4 = (k4 << 18) | (k4 >> (32 - 18)); k4 *= c1; h4 ^= k4;
- h4 = (h4 << 13) | (h4 >> (32 - 13)); h4 += h1; h4 = h4*5+0x32ac3b17;
- }
- uint k1, k2, k3;
- switch (len) // 0, 1, 2, 3
- {
- case 3:
- k3 = data[2];
- k3 *= c3; k3 = (k3 << 17) | (k3 >> (32 - 17)); k3 *= c4; h3 ^= k3;
- goto case;
- case 2:
- k2 = data[1];
- k2 *= c2; k2 = (k2 << 16) | (k2 >> (32 - 16)); k2 *= c3; h2 ^= k2;
- goto case;
- case 1:
- k1 = data[0];
- k1 *= c1; k1 = (k1 << 15) | (k1 >> (32 - 15)); k1 *= c2; h1 ^= k1;
- break;
- }
- hash = cast(size_t) h1 +
- ((cast(size_t) h2) << 32) +
- ((cast(size_t) h3) << 64) +
- ((cast(size_t) h4) << 96);
- }
- else
- {
- static assert(0, "Hash length must be either 32, 64, or 128 bits.");
- }
- }
-}
-
-/**
- * Takes an argument of an arbitrary type $(D_PARAM T) and calculates the hash
- * value.
- *
- * Hash calculation is supported for all scalar types. Aggregate types, like
- * $(D_KEYWORD struct)s, should implement `toHash`-function:
- * ---
- * size_t toHash() const
- * {
- * return hash;
- * }
- * ---
- *
- * For pointers and for scalar types implicitly convertible to `size_t` this
- * is an identity operation (i.e. the value is cast to `size_t` and returned
- * unaltered). Integer types wider than `size_t` are XOR folded down to
- * `size_t`. Other scalar types use an architecture-dependent hash function
- * based on their width and alignment.
- * If the type provides a `toHash`-function, only `toHash()` is called and its
- * result is returned.
- *
- * This function also accepts input ranges that contain hashable elements.
- * Individual values are combined then and the resulting hash is returned.
- *
- * Params:
- * T = Hashable type.
- * key = Hashable value.
- *
- * Returns: Calculated hash value.
- *
- * See_Also: $(LINK http://www.isthe.com/chongo/tech/comp/fnv/).
- */
-size_t hash(T)(auto ref T key)
-{
- static if (is(typeof(key.toHash()) == size_t))
- {
- return key.toHash();
- }
- else static if ((isIntegral!T || isSomeChar!T || isBoolean!T)
- && T.sizeof <= size_t.sizeof)
- {
- return cast(size_t) key;
- }
- else static if (isIntegral!T && T.sizeof > size_t.sizeof)
- {
- return cast(size_t) (key ^ (key >>> (size_t.sizeof * 8)));
- }
- else static if (isPointer!T || is(T : typeof(null)))
- {
- return (() @trusted => cast(size_t) key)();
- }
- else
- {
- Hasher hasher;
- hasher(key);
- return hasher.hash;
- }
-}
-
-/**
- * Determines whether $(D_PARAM hasher) is hash function for $(D_PARAM T), i.e.
- * it is callable with a value of type $(D_PARAM T) and returns a
- * $(D_PSYMBOL size_t) value.
- *
- * Params:
- * hasher = Hash function candidate.
- * T = Type to test the hash function with.
- *
- * Returns: $(D_KEYWORD true) if $(D_PARAM hasher) is a hash function for
- * $(D_PARAM T), $(D_KEYWORD false) otherwise.
- */
-template isHashFunction(alias hasher, T)
-{
- private alias wrapper = (T x) => hasher(x);
- enum bool isHashFunction = is(typeof(wrapper(T.init)) == size_t);
-}
-
-///
-@nogc nothrow pure @safe unittest
-{
- static assert(isHashFunction!(hash, int));
-}
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