github.com/weaviate/weaviate@v1.24.6/adapters/repos/db/vector/hnsw/distancer/asm/l2_inline.go (about)

     1  //                           _       _
     2  // __      _____  __ ___   ___  __ _| |_ ___
     3  // \ \ /\ / / _ \/ _` \ \ / / |/ _` | __/ _ \
     4  //  \ V  V /  __/ (_| |\ V /| | (_| | ||  __/
     5  //   \_/\_/ \___|\__,_| \_/ |_|\__,_|\__\___|
     6  //
     7  //  Copyright © 2016 - 2024 Weaviate B.V. All rights reserved.
     8  //
     9  //  CONTACT: hello@weaviate.io
    10  //
    11  
    12  package asm
    13  
    14  // Experiment with inlining and flattening the L2Squared distancer.
    15  // Theoretically, this should be faster than the loop version for small vectors
    16  // - it avoids the loop overhead
    17  // - it eliminates the bounds check by reversing the iteration
    18  // - it allows l22 and l24 to be inlined (the other ones are too large)
    19  // See go tool compile -d=ssa/check_bce/debug=1 -m l2_inline.go
    20  
    21  func l22(x []float32, y []float32) float32 {
    22  	diff := x[1] - y[1]
    23  	sum := diff * diff
    24  
    25  	diff = x[0] - y[0]
    26  	sum += diff * diff
    27  
    28  	return sum
    29  }
    30  
    31  func l24(x []float32, y []float32) float32 {
    32  	diff := x[3] - y[3]
    33  	sum := diff * diff
    34  
    35  	diff = x[2] - y[2]
    36  	sum += diff * diff
    37  
    38  	return l22(x, y) + sum
    39  }
    40  
    41  func l26(x []float32, y []float32) float32 {
    42  	diff := x[5] - y[5]
    43  	sum := diff * diff
    44  
    45  	diff = x[4] - y[4]
    46  	sum += diff * diff
    47  
    48  	return l24(x, y) + sum
    49  }
    50  
    51  func l28(x []float32, y []float32) float32 {
    52  	diff := x[7] - y[7]
    53  	sum := diff * diff
    54  
    55  	diff = x[6] - y[6]
    56  	sum += diff * diff
    57  
    58  	diff = x[5] - y[5]
    59  	sum += diff * diff
    60  
    61  	diff = x[4] - y[4]
    62  	sum += diff * diff
    63  
    64  	return l24(x, y) + sum
    65  }
    66  
    67  func l210(x []float32, y []float32) float32 {
    68  	diff := x[9] - y[9]
    69  	sum := diff * diff
    70  
    71  	diff = x[8] - y[8]
    72  	sum += diff * diff
    73  
    74  	diff = x[7] - y[7]
    75  	sum += diff * diff
    76  
    77  	diff = x[6] - y[6]
    78  	sum += diff * diff
    79  
    80  	diff = x[5] - y[5]
    81  	sum += diff * diff
    82  
    83  	diff = x[4] - y[4]
    84  	sum += diff * diff
    85  
    86  	return l24(x, y) + sum
    87  }
    88  
    89  func l212(x []float32, y []float32) float32 {
    90  	diff := x[11] - y[11]
    91  	sum := diff * diff
    92  
    93  	diff = x[10] - y[10]
    94  	sum += diff * diff
    95  
    96  	diff = x[9] - y[9]
    97  	sum += diff * diff
    98  
    99  	diff = x[8] - y[8]
   100  	sum += diff * diff
   101  
   102  	diff = x[7] - y[7]
   103  	sum += diff * diff
   104  
   105  	diff = x[6] - y[6]
   106  	sum += diff * diff
   107  
   108  	diff = x[5] - y[5]
   109  	sum += diff * diff
   110  
   111  	diff = x[4] - y[4]
   112  	sum += diff * diff
   113  
   114  	return l24(x, y) + sum
   115  }