Merge pull request #86 from tarterp/add_chrysalis_hybrid_murmur

added chrysalis hybrid murmur

Author: herrcore

algorithms/chrysalis_hybrid_murmur.py

@@ -0,0 +1,122 @@
+DESCRIPTION = '''
+    A hybrid hashing algorithm that processes short strings with a standard 
+    iterative loop and switches to a parallelized four-accumulator strategy for 
+    strings of 16 bytes or more. The intermediate result is finalized using a 
+    modified MurmurHash3 avalanche mixer to produce the output.
+'''
+TYPE = 'unsigned_int'
+TEST_1 = 3873075608
+
+def rol4(value, count):
+    """Rotate Left 32-bit"""
+    count %= 32
+    value &= 0xFFFFFFFF
+    return ((value << count) | (value >> (32 - count))) & 0xFFFFFFFF
+
+def ror4(value, count):
+    """Rotate Right 32-bit"""
+    count %= 32
+    value &= 0xFFFFFFFF
+    return ((value >> count) | (value << (32 - count))) & 0xFFFFFFFF
+
+def hash(data):
+
+    # Convert string to list of integer bytes
+    if isinstance(data, str):
+        data = [ord(c) for c in data]
+    else:
+        data = list(data)
+
+    data_len = len(data)
+    idx = 0
+    seed = 0
+    
+    # ---------------------------------------------------------
+    # Path 1: Long Strings (>= 16 chars)
+    # ---------------------------------------------------------
+    if data_len >= 0x10:
+        accumulator_1 = 0x2D10317
+        accumulator_2 = 0x64998966
+        accumulator_3 = 0xDEADBEEF
+        accumulator_4 = 0x4076453E
+        
+        # Process in blocks of 4 bytes
+        while data_len >= 4:
+            # Accumulator 1
+            term = (0x9E3779B1 * accumulator_1) & 0xFFFFFFFF
+            sub  = (0x3B5C4B9 * data[idx]) & 0xFFFFFFFF
+            accumulator_1 = rol4((term - sub) & 0xFFFFFFFF, 13)
+            
+            # Accumulator 2
+            term = (0x9E3779B1 * accumulator_2) & 0xFFFFFFFF
+            sub  = (0x3B5C4B9 * data[idx + 1]) & 0xFFFFFFFF
+            accumulator_2 = rol4((term - sub) & 0xFFFFFFFF, 13)
+            
+            # Accumulator 3
+            term = (0x9E3779B1 * accumulator_3) & 0xFFFFFFFF
+            sub  = (0x3B5C4B9 * data[idx + 2]) & 0xFFFFFFFF
+            accumulator_3 = rol4((term - sub) & 0xFFFFFFFF, 13)
+            
+            # Accumulator 4
+            v12  = data[idx + 3]
+            term = (0x9E3779B1 * accumulator_4) & 0xFFFFFFFF
+            sub  = (0x3B5C4B9 * v12) & 0xFFFFFFFF
+            accumulator_4 = rol4((term - sub) & 0xFFFFFFFF, 13)
+            
+            idx += 4
+            # CRITICAL: The C code decrements the length variable here.
+            # This affects the loop condition for the "Tail Loop" below.
+            data_len -= 4
+
+        # Merge accumulators into v13
+        v13 = (rol4(accumulator_1, 1) + 
+               rol4(accumulator_2, 7) + 
+               rol4(accumulator_3, 12) + 
+               ror4(accumulator_4, 14)) & 0xFFFFFFFF
+               
+        # Calculate specific seed for long strings
+        # seed = 0x842A6D03 - 0x61C8864F * v13
+        mult_res = (0x61C8864F * v13) & 0xFFFFFFFF
+        seed = (0x842A6D03 - mult_res) & 0xFFFFFFFF
+        
+    # ---------------------------------------------------------
+    # Path 2: Short Strings (< 16 chars)
+    # ---------------------------------------------------------
+    else:
+        seed = 0xF50426A0
+
+    # ---------------------------------------------------------
+    # Common Tail Loop
+    # ---------------------------------------------------------
+    # NOTE: If the "Long String" path was taken, 'idx' is now large (e.g., 16)
+    # and 'data_len' is small (e.g., 2).
+    # Since idx >= data_len, this loop is SKIPPED for long strings.
+    # This loop ONLY runs fully for short strings.
+    
+    i = (idx + seed) & 0xFFFFFFFF
+    
+    while idx < data_len:
+        v16 = data[idx]
+        idx += 1
+        
+        # i = 0x9E3779B1 * __ROL4__(i + 0x165667B1 * v16, 11)
+        term_inner = (i + (0x165667B1 * v16)) & 0xFFFFFFFF
+        rotated = rol4(term_inner, 11)
+        i = (0x9E3779B1 * rotated) & 0xFFFFFFFF
+
+    # ---------------------------------------------------------
+    # Final Mixing
+    # ---------------------------------------------------------
+    # Term 1: (0x85EBCA77 * (i ^ (i >> 15)))
+    term1 = (0x85EBCA77 * (i ^ (i >> 15))) & 0xFFFFFFFF
+    
+    # Term 2: term1 ^ (term1 >> 13)
+    term2 = term1 ^ (term1 >> 13)
+    
+    # Term 3: 0xC2B2AE3D * term2
+    term3 = (0xC2B2AE3D * term2) & 0xFFFFFFFF
+    
+    # Final: term3 ^ (term3 >> 16)
+    final_hash = term3 ^ (term3 >> 16)
+    
+    return final_hash