source: tests/concurrent/examples/quickSort.cfa@ c957e7f

ADT arm-eh ast-experimental cleanup-dtors enum forall-pointer-decay jacob/cs343-translation jenkins-sandbox new-ast new-ast-unique-expr pthread-emulation qualifiedEnum
Last change on this file since c957e7f was f8cd310, checked in by Peter A. Buhr <pabuhr@…>, 7 years ago

update file names in emacs compile directive
  • Property mode set to 100644
File size: 6.3 KB
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1//
2// Cforall Version 1.0.0 Copyright (C) 2017 University of Waterloo
3//
4// The contents of this file are covered under the licence agreement in the
5// file "LICENCE" distributed with Cforall.
6//
7// quickSort.c -- In-place concurrent quick-sort: threads are created to partition to a specific depth, then sequential
8// recursive-calls are use to sort each partition.
9//
10// Author : Peter A. Buhr
11// Created On : Wed Dec 6 12:15:52 2017
12// Last Modified By : Peter A. Buhr
13// Last Modified On : Fri Mar 22 13:42:01 2019
14// Update Count : 170
15//
16
17#include <fstream.hfa>
18#include <stdlib.hfa>
19#include <kernel.hfa>
20#include <thread.hfa>
21#include <string.h> // strcmp
22
23thread Quicksort {
24 int * values; // communication variables
25 int low, high, depth;
26};
27
28void ?{}( Quicksort & qs, int values[], int size, int depth ) {
29 qs.values = values; qs.low = 0; qs.high = size; qs.depth = depth;
30} // Quicksort
31
32void main( Quicksort & qs ) { // thread starts here
33 // nested routines: information hiding
34
35 void ?{}( Quicksort & qs, int values[], int low, int high, int depth ) {
36 qs.values = values; qs.low = low; qs.high = high; qs.depth = depth;
37 } // Quicksort
38
39 void sort( int values[], int low, int high, int depth ) {
40 int left, right; // index to left/right-hand side of the values
41 int pivot; // pivot value of values
42 int swap; // temporary
43
44 //verify(); // check for stack overflow due to recursion
45
46 // partition while 2 or more elements in the array
47 if ( low < high ) {
48 pivot = values[low + ( high - low ) / 2];
49 left = low;
50 right = high;
51
52 // partition: move values less < pivot before the pivot and values > pivot after the pivot
53 do {
54 while ( values[left] < pivot ) left += 1; // changed values[left] < pivot
55 while ( pivot < values[right] ) right -= 1;
56 if ( left <= right ) {
57 swap = values[left]; // interchange values
58 values[left] = values[right];
59 values[right] = swap;
60 left += 1;
61 right -= 1;
62 } // if
63 } while ( left <= right );
64
65 // restrict number of tasks to slightly greater than number of processors
66 if ( depth > 0 ) {
67 depth -= 1;
68 Quicksort rqs = { values, low, right, depth }; // concurrently sort upper half
69 //Quicksort lqs( values, left, high, depth ); // concurrently sort lower half
70 sort( values, left, high, depth ); // concurrently sort lower half
71 } else {
72 sort( values, low, right, 0 ); // sequentially sort lower half
73 sort( values, left, high, 0 ); // sequentially sort upper half
74 } // if
75 } // if
76 } // sort
77
78 with( qs ) {
79 sort( values, low, high, depth );
80 } // with
81} // main
82
83
84bool convert( int & val, const char * nptr ) { // convert C string to integer
85 char * eptr;
86 int temp = strto( nptr, &eptr, 10 ); // do not change val on false
87 // true => entire string valid with no extra characters
88 return *nptr != '\0' && *eptr == '\0' ? val = temp, true : false;
89} // convert
90
91void usage( char * argv[] ) {
92 sout | "Usage:" | argv[0] | "( -s unsorted-file [ sorted-file ] | -t size (>= 0) [ depth (>= 0) ] )";
93 exit( EXIT_FAILURE ); // TERMINATE!
94} // usage
95
96
97int main( int argc, char * argv[] ) {
98 ifstream & unsortedfile = sin;
99 ofstream & sortedfile = sout; // default value
100 int depth = 0, size;
101
102 if ( argc != 1 ) { // do not use defaults
103 if ( argc < 2 || argc > 4 ) usage( argv ); // wrong number of options
104 if ( strcmp( argv[1], "-t" ) == 0 ) { // timing ?
105 &unsortedfile = (ifstream *)0; // no input
106 choose ( argc ) {
107 case 4:
108 if ( ! convert( depth, argv[3] ) || depth < 0 ) usage( argv );
109 fallthrough;
110 case 3:
111 if ( ! convert( size, argv[2] ) || size < 0 ) usage( argv );
112 } // choose
113 } else { // sort file
114 choose ( argc ) {
115 case 3:
116 &sortedfile = new( (const char *)argv[2] ); // open the output file
117 if ( fail( sortedfile ) ) {
118 serr | "Error! Could not open sorted output file \"" | argv[2] | "\"";
119 usage( argv );
120 } // if
121 fallthrough;
122 case 2:
123 &unsortedfile = new( (const char *)argv[1] ); // open the input file
124 if ( fail( unsortedfile ) ) {
125 serr | "Error! Could not open unsorted input file \"" | argv[1] | "\"";
126 usage( argv );
127 } // if
128 } // choose
129 } // if
130 } // if
131 sortedfile | nlOff; // turn off auto newline
132
133 enum { ValuesPerLine = 22 }; // number of values printed per line
134
135 if ( &unsortedfile ) { // generate output ?
136 for () {
137 unsortedfile | size; // read number of elements in the list
138 if ( eof( unsortedfile ) ) break;
139 int * values = alloc( size ); // values to be sorted, too large to put on stack
140 for ( int counter = 0; counter < size; counter += 1 ) { // read unsorted numbers
141 unsortedfile | values[counter];
142 if ( counter != 0 && counter % ValuesPerLine == 0 ) sortedfile | nl | " ";
143 sortedfile | values[counter];
144 if ( counter < size - 1 && (counter + 1) % ValuesPerLine != 0 ) sortedfile | ' ';
145 } // for
146 sortedfile | nl;
147 if ( size > 0 ) { // values to sort ?
148 Quicksort QS = { values, size - 1, 0 }; // sort values
149 } // wait until sort tasks terminate
150 for ( int counter = 0; counter < size; counter += 1 ) { // print sorted list
151 if ( counter != 0 && counter % ValuesPerLine == 0 ) sortedfile | nl | " ";
152 sortedfile | values[counter];
153 if ( counter < size - 1 && (counter + 1) % ValuesPerLine != 0 ) sortedfile | ' ';
154 } // for
155 sortedfile | nl | nl;
156
157 delete( values );
158 } // for
159 if ( &unsortedfile != &sin ) delete( &unsortedfile ); // close input/output files
160 if ( &sortedfile != &sout ) delete( &sortedfile );
161 } else {
162 processor processors[ (1 << depth) - 1 ] __attribute__(( unused )); // create 2^depth-1 kernel threads
163
164 int * values = alloc( size ); // values to be sorted, too large to put on stack
165 for ( int counter = 0; counter < size; counter += 1 ) { // generate unsorted numbers
166 values[counter] = size - counter; // descending values
167 } // for
168 {
169 Quicksort QS = { values, size - 1, depth }; // sort values
170 } // wait until sort tasks terminate
171
172 // for ( int counter = 0; counter < size - 1; counter += 1 ) { // check sorting
173 // if ( values[counter] > values[counter + 1] ) abort();
174 // } // for
175
176 delete( values );
177 } // if
178} // main
179
180// Local Variables: //
181// tab-width: 4 //
182// compile-command: "cfa quickSort.cfa" //
183// End: //
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