gcc/testsuite/gcc.dg/vect/bb-slp-pr81635-1.c

   1 /* { dg-do compile } */
   2 /* { dg-additional-options "-fno-tree-loop-vectorize" } */
   3 /* { dg-require-effective-target vect_double } */
   4 /* { dg-require-effective-target lp64 } */
   5
   6 void
   7 f1 (double *p, double *q)
   8 {
   9   p = (double *) __builtin_assume_aligned (p, sizeof (double) * 2);
  10   q = (double *) __builtin_assume_aligned (q, sizeof (double) * 2);
  11   for (unsigned int i = 0; i < 1000; i += 4)
  12     {
  13       double a = q[i] + p[i];
  14       double b = q[i + 1] + p[i + 1];
  15       q[i] = a;
  16       q[i + 1] = b;
  17     }
  18 }
  19
  20 void
  21 f2 (double *p, double *q)
  22 {
  23   p = (double *) __builtin_assume_aligned (p, sizeof (double) * 2);
  24   q = (double *) __builtin_assume_aligned (q, sizeof (double) * 2);
  25   for (unsigned int i = 2; i < ~0U - 4; i += 4)
  26     {
  27       double a = q[i] + p[i];
  28       double b = q[i + 1] + p[i + 1];
  29       q[i] = a;
  30       q[i + 1] = b;
  31     }
  32 }
  33
  34 void
  35 f3 (double *p, double *q)
  36 {
  37   p = (double *) __builtin_assume_aligned (p, sizeof (double) * 2);
  38   q = (double *) __builtin_assume_aligned (q, sizeof (double) * 2);
  39   for (unsigned int i = 0; i < ~0U - 3; i += 4)
  40     {
  41       double a = q[i + 2] + p[i + 2];
  42       double b = q[i + 3] + p[i + 3];
  43       q[i + 2] = a;
  44       q[i + 3] = b;
  45     }
  46 }
  47
  48 void
  49 f4 (double *p, double *q)
  50 {
  51   p = (double *) __builtin_assume_aligned (p, sizeof (double) * 2);
  52   q = (double *) __builtin_assume_aligned (q, sizeof (double) * 2);
  53   for (unsigned int i = 0; i < 500; i += 6)
  54     for (unsigned int j = 0; j < 500; j += 4)
  55       {
  56         double a = q[j] + p[i];
  57         double b = q[j + 1] + p[i + 1];
  58         q[i] = a;
  59         q[i + 1] = b;
  60       }
  61 }
  62
  63 void
  64 f5 (double *p, double *q)
  65 {
  66   p = (double *) __builtin_assume_aligned (p, sizeof (double) * 2);
  67   q = (double *) __builtin_assume_aligned (q, sizeof (double) * 2);
  68   for (unsigned int i = 2; i < 1000; i += 4)
  69     {
  70       double a = q[i - 2] + p[i - 2];
  71       double b = q[i - 1] + p[i - 1];
  72       q[i - 2] = a;
  73       q[i - 1] = b;
  74     }
  75 }
  76
  77 double p[1000];
  78 double q[1000];
  79
  80 void
  81 f6 (int n)
  82 {
  83   for (unsigned int i = 0; i < n; i += 4)
  84     {
  85       double a = q[i] + p[i];
  86       double b = q[i + 1] + p[i + 1];
  87       q[i] = a;
  88       q[i + 1] = b;
  89     }
  90 }
  91
  92 /* { dg-final { scan-tree-dump-times "optimized: basic block" 6 "slp1" } } */