implement optimizations

src/commonMain/kotlin/com/infendro/hash/blake2/Blake2s.kt

@@ -1,9 +1,10 @@
 package com.infendro.hash.blake2
 
-import com.infendro.bytearray.ByteOrder.LITTLE_ENDIAN
-import com.infendro.bytearray.toUByteArray
-import com.infendro.bytearray.toUIntArray
+import com.infendro.bytes.ByteOrder.LITTLE_ENDIAN
+import com.infendro.bytes.bytearray.copyInto
+import com.infendro.bytes.intarray.toByteArray
 import com.infendro.hash.HashFunction
+import com.infendro.hash.util.ceilPow2
 
 class Blake2s(
     override val bytes: Int,
@@ -20,7 +21,7 @@ class Blake2s(
         0x3c6ef372U, 0xa54ff53aU,
         0x510e527fU, 0x9b05688cU,
         0x1f83d9abU, 0x5be0cd19U,
-    )
+    ).asIntArray()
 
     private val sigma = arrayOf(
         intArrayOf(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15),
@@ -35,46 +36,42 @@ class Blake2s(
         intArrayOf(10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0),
     )
 
-    override fun hash(value: UByteArray): UByteArray {
-        val l = value.size.toULong()
+    override fun hashInto(value: ByteArray, destination: ByteArray) {
+        val length = value.size.toULong()
+        val input = pad(value)
         val h = initial.copyOf()
-        h[0] = h[0] xor (0x01010000U or bytes.toUInt())
+        h[0] = h[0] xor (0x01010000 or bytes)
+        val m = IntArray(16)
+        val v = IntArray(16)
         var t = 0U
 
-        val blocks = pad(value)
-            .chunked(64) { it.toUByteArray() }
-        for ((i, block) in blocks.withIndex()) {
-            t += minOf(l - t, 64UL).toUInt()
-            compress(h, block, t, i == blocks.lastIndex)
+        for (i in input.indices step block) {
+            t += minOf(length - t, 64UL).toUInt()
+            compress(h, input, i, m, v, t, t < 1024UL)
         }
-
-        return h.toUByteArray(LITTLE_ENDIAN).sliceArray(0..<bytes)
+        h.toByteArray(LITTLE_ENDIAN).copyInto(destination, endIndex = bytes)
     }
 
-    private fun pad(
-        value: UByteArray,
-    ): UByteArray {
-        return buildList {
-            addAll(value)
-            if (isEmpty()) add(0x00U)
-            while (size % 64 != 0) {
-                add(0x00U)
-            }
-        }.toUByteArray()
+    private fun pad(value: ByteArray): ByteArray {
+        val size = maxOf(ceilPow2(value.size, block), block)
+        val result = ByteArray(size)
+        value.copyInto(result)
+        return result
     }
 
     private fun compress(
-        h: UIntArray,
-        block: UByteArray,
+        h: IntArray,
+        value: ByteArray,
+        offset: Int,
+        m: IntArray,
+        v: IntArray,
         t: UInt,
         last: Boolean,
     ) {
-        val m = block.toUIntArray()
-        val v = UIntArray(16)
+        value.copyInto(m, startIndex = offset, endIndex = offset + block)
         for (i in 0..<8) v[i] = h[i]
         for (i in 0..<8) v[i + 8] = initial[i]
-
-        v[12] = v[12] xor t
+        v[12] = v[12] xor t.toInt()
         if (last) v[14] = v[14].inv()
 
         repeat(10) { r ->
@@ -91,20 +88,12 @@ class Blake2s(
             mix(v, 3, 4, 9, 14, m[s[14]], m[s[15]])
         }
 
-        for (i in 0..7) {
+        for (i in 0..<8) {
             h[i] = h[i] xor v[i] xor v[i + 8]
         }
     }
 
-    private fun mix(
-        v: UIntArray,
-        a: Int,
-        b: Int,
-        c: Int,
-        d: Int,
-        x: UInt,
-        y: UInt,
-    ) {
+    private fun mix(v: IntArray, a: Int, b: Int, c: Int, d: Int, x: Int, y: Int) {
         v[a] += v[b] + x
         v[d] = (v[d] xor v[a]).rotateRight(16)
         v[c] += v[d]