time-to-botec

Benchmark sampling in different programming languages
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init.js (3092B)

      1 /**
      2 * @license Apache-2.0
      3 *
      4 * Copyright (c) 2021 The Stdlib Authors.
      5 *
      6 * Licensed under the Apache License, Version 2.0 (the "License");
      7 * you may not use this file except in compliance with the License.
      8 * You may obtain a copy of the License at
      9 *
     10 *    http://www.apache.org/licenses/LICENSE-2.0
     11 *
     12 * Unless required by applicable law or agreed to in writing, software
     13 * distributed under the License is distributed on an "AS IS" BASIS,
     14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     15 * See the License for the specific language governing permissions and
     16 * limitations under the License.
     17 */
     18 
     19 'use strict';
     20 
     21 // MODULES //
     22 
     23 var bytesPerElement = require( './../../../base/bytes-per-element' );
     24 var range = require( './range.js' );
     25 var sort2ins = require( './sort2ins.js' );
     26 var copy = require( './copy_array.js' );
     27 var permute = require( './permute.js' );
     28 var defaults = require( './defaults.js' );
     29 
     30 
     31 // MAIN //
     32 
     33 /**
     34 * Initialize block data (shape, strides, block size).
     35 *
     36 * ## Notes
     37 *
     38 * -   The returned object has the following properties:
     39 *
     40 *     -   **sh**: dimensions sorted in loop order.
     41 *     -   **sx**: input ndarray strides sorted in loop order.
     42 *     -   **sy**: output ndarray strides sorted in loop order.
     43 *     -   **bsize**: block size (in units of elements).
     44 *
     45 * @private
     46 * @param {Object} x - object containing input ndarray meta data
     47 * @param {string} x.dtype - data type
     48 * @param {Collection} x.data - data buffer
     49 * @param {NonNegativeIntegerArray} x.shape - dimensions
     50 * @param {IntegerArray} x.strides - stride lengths
     51 * @param {NonNegativeInteger} x.offset - index offset
     52 * @param {string} x.order - specifies whether `x` is row-major (C-style) or column-major (Fortran-style)
     53 * @param {Object} y - object containing output ndarray meta data
     54 * @param {string} y.dtype - data type
     55 * @param {Collection} y.data - data buffer
     56 * @param {NonNegativeIntegerArray} y.shape - dimensions
     57 * @param {IntegerArray} y.strides - stride lengths
     58 * @param {NonNegativeInteger} y.offset - index offset
     59 * @param {string} y.order - specifies whether `y` is row-major (C-style) or column-major (Fortran-style)
     60 * @returns {Object} block data
     61 */
     62 function init( x, y ) {
     63 	var bsize;
     64 	var idx;
     65 	var nbx;
     66 	var nby;
     67 	var sh;
     68 	var sx;
     69 	var sy;
     70 
     71 	// Initialize a loop interchange index array for generating a loop order permutation:
     72 	sh = x.shape;
     73 	idx = range( sh.length );
     74 
     75 	// Sort the input array strides in increasing order (of magnitude):
     76 	sx = copy( x.strides );
     77 	sort2ins( sx, idx );
     78 
     79 	// Permute the shape and output array strides based on the sorted input array strides:
     80 	sh = permute( sh, idx );
     81 	sy = permute( y.strides, idx );
     82 
     83 	// Determine the block size...
     84 	nbx = bytesPerElement( x.dtype );
     85 	nby = bytesPerElement( y.dtype );
     86 	if ( nbx === null || nby === null ) {
     87 		bsize = defaults.BLOCK_SIZE_IN_ELEMENTS;
     88 	} else if ( nbx > nby ) {
     89 		bsize = ( defaults.BLOCK_SIZE_IN_BYTES/nbx )|0;
     90 	} else {
     91 		bsize = ( defaults.BLOCK_SIZE_IN_BYTES/nby )|0;
     92 	}
     93 	return {
     94 		'sh': sh,
     95 		'sx': sx,
     96 		'sy': sy,
     97 		'bsize': bsize
     98 	};
     99 }
    100 
    101 
    102 // EXPORTS //
    103 
    104 module.exports = init;