/ tests / qsort_perf.c
qsort_perf.c
  1  /*
  2   * Randomized test for qsort() routine.
  3   *
  4   * Includes code derived from stdlib/FreeBSD/qsort.c and the copyright header
  5   * in that file applies.
  6   */
  7  
  8  #include <sys/cdefs.h>
  9  
 10  #include <assert.h>
 11  #include <stdio.h>
 12  #include <stdlib.h>
 13  #include <darwintest.h>
 14  #include <darwintest_utils.h>
 15  
 16  static void qsort1(void *aa, size_t n, size_t es,
 17          int (*cmp)(const void *, const void *));
 18  
 19  static int
 20  cmp_int(const void *aa, const void *bb)
 21  {
 22      int a, b;
 23  
 24      a = *(const int *)aa;
 25      b = *(const int *)bb;
 26      return(a - b);
 27  }
 28  
 29  #define nelm 1000000
 30  
 31  T_DECL(qsort_perf, "qsort perf test", T_META_CHECK_LEAKS(NO))
 32  {
 33      int i;
 34      int arr[nelm];
 35      int save[nelm];
 36      uint64_t time_elapsed;
 37  
 38      // ----- 25-75 -----
 39  
 40      int k = nelm/4;
 41      for (i = 0; i < k; i++) {
 42          save[i] = i;
 43      }
 44      for (i = k; i < nelm; i++) {
 45          save[i] = i - k;
 46      }
 47  
 48      bcopy(save, arr, sizeof(arr));
 49      dt_timer_start("25-75 (qsort)");
 50      qsort(arr, nelm, sizeof(arr[0]), cmp_int);
 51      time_elapsed = dt_timer_stop("25-75 (qsort)");
 52      T_LOG("25-75 (qsort): %lld ms", time_elapsed / NSEC_PER_MSEC);
 53      for (i = 1; i < nelm; i++) {
 54          if(arr[i - 1] > arr[i]) {
 55              T_ASSERT_FAIL("arr[%d]=%d > arr[%d]=%d", i - 1, arr[i - 1], i, arr[i]);
 56              break;
 57          }
 58      }
 59  
 60      bcopy(save, arr, sizeof(arr));
 61      dt_timer_start("25-75 (Bentley)");
 62      qsort1(arr, nelm, sizeof(arr[0]), cmp_int);
 63      time_elapsed = dt_timer_stop("25-75 (Bentley)");
 64      T_LOG("25-75 (Bentley): %lld ms", time_elapsed / NSEC_PER_MSEC);
 65      for (i = 1; i < nelm; i++) {
 66          if(arr[i - 1] > arr[i]) {
 67              T_ASSERT_FAIL("arr[%d]=%d > arr[%d]=%d", i - 1, arr[i - 1], i, arr[i]);
 68              break;
 69          }
 70      }
 71      // ----- 50-50 -----
 72  
 73      k = nelm/2;
 74      for (i = 0; i < k; i++) {
 75          save[i] = i;
 76      }
 77      for (i = k; i < nelm; i++) {
 78          save[i] = i - k;
 79      }
 80  
 81      bcopy(save, arr, sizeof(arr));
 82      dt_timer_start("50-50 (qsort)");
 83      qsort(arr, nelm, sizeof(arr[0]), cmp_int);
 84      time_elapsed = dt_timer_stop("50-50 (qsort)");
 85      T_LOG("50-50 (qsort): %lld ms", time_elapsed / NSEC_PER_MSEC);
 86      for (i = 1; i < nelm; i++) {
 87          if(arr[i - 1] > arr[i]) {
 88              T_ASSERT_FAIL("arr[%d]=%d > arr[%d]=%d", i - 1, arr[i - 1], i, arr[i]);
 89              break;
 90          }
 91      }
 92  
 93      bcopy(save, arr, sizeof(arr));
 94      dt_timer_start("50-50 (Bentley)");
 95      qsort1(arr, nelm, sizeof(arr[0]), cmp_int);
 96      time_elapsed = dt_timer_stop("50-50 (Bentley)");
 97      T_LOG("50-50 (Bentley): %lld ms", time_elapsed / NSEC_PER_MSEC);
 98      for (i = 1; i < nelm; i++) {
 99          if(arr[i - 1] > arr[i]) {
100              T_ASSERT_FAIL("arr[%d]=%d > arr[%d]=%d", i - 1, arr[i - 1], i, arr[i]);
101              break;
102          }
103      }
104  
105      // ----- median-of-3 killer -----
106  
107      k = nelm / 2;
108      for (i = 1; i <= k; i++) {
109          if(i % 2 == 1) {
110              save[i - 1] = i;
111              save[i] = k + i;
112          }
113          save[k + i - 1] = 2 * i;
114      }
115  
116      bcopy(save, arr, sizeof(arr));
117      dt_timer_start("median-of-3 killer (qsort)");
118      qsort(arr, nelm, sizeof(arr[0]), cmp_int);
119      time_elapsed = dt_timer_stop("median-of-3 killer (qsort)");
120      T_LOG("median-of-3 (qsort): %lld ms", time_elapsed / NSEC_PER_MSEC);
121      for (i = 1; i < nelm; i++) {
122          if(arr[i - 1] > arr[i]) {
123              T_ASSERT_FAIL("arr[%d]=%d > arr[%d]=%d", i - 1, arr[i - 1], i, arr[i]);
124          }
125      }
126  
127      bcopy(save, arr, sizeof(arr));
128      dt_timer_start("median-of-3 killer (Bentley)");
129      qsort1(arr, nelm, sizeof(arr[0]), cmp_int);
130      time_elapsed = dt_timer_stop("median-of-3 killer (Bentley)");
131      T_LOG("median-of-3 (Bentley): %lld ms", time_elapsed / NSEC_PER_MSEC);
132      for (i = 1; i < nelm; i++) {
133          if(arr[i - 1] > arr[i]) {
134              T_ASSERT_FAIL("arr[%d]=%d > arr[%d]=%d", i - 1, arr[i - 1], i, arr[i]);
135          }
136      }
137  
138      // ----- random -----
139  
140      for (i = 0; i < nelm; i++) {
141          save[i] = random();
142      }
143  
144      bcopy(save, arr, sizeof(arr));
145      dt_timer_start("random (qsort)");
146      qsort(arr, nelm, sizeof(arr[0]), cmp_int);
147      time_elapsed = dt_timer_stop("random (qsort)");
148      T_LOG("random (qsort): %lld ms", time_elapsed / NSEC_PER_MSEC);
149      for (i = 1; i < nelm; i++) {
150          if(arr[i - 1] > arr[i]) {
151              T_ASSERT_FAIL("arr[%d]=%d > arr[%d]=%d", i - 1, arr[i - 1], i, arr[i]);
152          }
153      }
154  
155  
156      bcopy(save, arr, sizeof(arr));
157      dt_timer_start("random (Bentley)");
158      qsort1(arr, nelm, sizeof(arr[0]), cmp_int);
159      time_elapsed = dt_timer_stop("random (Bentley)");
160      T_LOG("random (Bentley): %lld ms", time_elapsed / NSEC_PER_MSEC);
161      for (i = 1; i < nelm; i++) {
162          if(arr[i - 1] > arr[i]) {
163              T_ASSERT_FAIL("arr[%d]=%d > arr[%d]=%d", i - 1, arr[i - 1], i, arr[i]);
164          }
165      }
166  
167      T_PASS("All tests completed successfully.");
168  }
169  
170  /* qsort1 -- qsort interface implemented by faster quicksort */
171  
172  #define SWAPINIT(a, es) swaptype =                            \
173      (a - (char*) 0) % sizeof(long) || es % sizeof(long) ? 2 : \
174      es == sizeof(long) ? 0 : 1;
175  #define swapcode(TYPE, parmi, parmj, n) {  \
176      long i = (n) / sizeof(TYPE);           \
177      register TYPE *pi = (TYPE *) (parmi);  \
178      register TYPE *pj = (TYPE *) (parmj);  \
179      do {                                   \
180          register TYPE t = *pi;             \
181          *pi++ = *pj;                       \
182          *pj++ = t;                         \
183      } while (--i > 0);                     \
184  }
185  static void swapfunc(char *a, char *b, int n, int swaptype)
186  {   if (swaptype <= 1) swapcode(long, a, b, n)
187      else swapcode(char, a, b, n)
188  }
189  #define swap(a, b)                         \
190      if (swaptype == 0) {                   \
191          long t = * (long *) (a);           \
192          * (long *) (a) = * (long *) (b);   \
193          * (long *) (b) = t;                \
194      } else                                 \
195          swapfunc(a, b, es, swaptype)
196  #define vecswap(a, b, n) if (n > 0) swapfunc(a, b, n, swaptype)
197  
198  #define min(x, y) ((x)<=(y) ? (x) : (y))
199  
200  static char *med3(char *a, char *b, char *c, int (*cmp)(const void *, const void *))
201  {
202      return cmp(a, b) < 0 ?
203              (cmp(b, c) < 0 ? b : (cmp(a, c) < 0 ? c : a ) )
204              : (cmp(b, c) > 0 ? b : (cmp(a, c) < 0 ? a : c ) );
205  }
206  
207  static void
208  qsort1(void *aa, size_t n, size_t es,
209        int (*cmp)(const void *, const void *))
210  {
211  	char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
212  	int  d, r, swaptype;
213  	char *a = aa;
214  
215  	SWAPINIT(a, es);
216  	if (n < 7) { /* Insertion sort on small arrays */
217  		for (pm = a + es; pm < a + n*es; pm += es)
218  			for (pl = pm; pl > a && cmp(pl-es, pl) > 0; pl -= es)
219  				swap(pl, pl-es);
220  		return;
221  	}
222  	pm = a + (n/2) * es;
223  	if (n > 7) {
224  		pl = a;
225  		pn = a + (n-1) * es;
226  		if (n > 40) { /* On big arrays, pseudomedian of 9 */
227  			d = (n/8) * es;
228  			pl = med3(pl, pl+d, pl+2*d, cmp);
229  			pm = med3(pm-d, pm, pm+d, cmp);
230  			pn = med3(pn-2*d, pn-d, pn, cmp);
231  		}
232  		pm = med3(pl, pm, pn, cmp); /* On mid arrays, med of 3 */
233  	}
234  	swap(a, pm); /* On tiny arrays, partition around middle */
235  	pa = pb = a + es;
236  	pc = pd = a + (n-1)*es;
237  	for (;;) {
238  		while (pb <= pc && (r = cmp(pb, a)) <= 0) {
239  			if (r == 0) { swap(pa, pb); pa += es; }
240  			pb += es;
241  		}
242  		while (pb <= pc && (r = cmp(pc, a)) >= 0) {
243  			if (r == 0) { swap(pc, pd); pd -= es; }
244  			pc -= es;
245  		}
246  		if (pb > pc) break;
247  		swap(pb, pc);
248  		pb += es;
249  		pc -= es;
250  	}
251  	pn = a + n*es;
252  	r = min(pa-a,  pb-pa);    vecswap(a,  pb-r, r);
253  	r = min(pd-pc, pn-pd-es); vecswap(pb, pn-r, r);
254  	if ((r = pb-pa) > es) qsort1(a, r/es, es, cmp);
255  	if ((r = pd-pc) > es) qsort1(pn-r, r/es, es, cmp);
256  }