gcc/testsuite/gcc.dg/tree-ssa/loop-interchange-5.c

   1 /* { dg-do run } */
   2 /* { dg-options "-O2 -floop-interchange -fdump-tree-linterchange-details" } */
   3 /* { dg-skip-if "too big data segment" { avr-*-* visium-*-* } } */
   4
   5 #define M 256
   6 int a[M][M], b[M][M], c[M][M], d[M][M];
   7 void __attribute__((noinline))
   8 matrix_mul_1 (int n)
   9 {
  10   for (int i = 0; i < n; i++)
  11     for (int j = 0; j < n; j++)
  12       for (int k = 0; k < n; k++)
  13         c[i][j] = c[i][j] + a[i][k]*b[k][j];
  14 }
  15
  16 void __attribute__((noinline))
  17 matrix_mul_2 (int n)
  18 {
  19   for (int i = 0; i < n; i++)
  20     {
  21       for (int j = 0; j < n; j++)
  22         {
  23           for (int k = 0; k < n; k++)
  24             d[i][j] = d[i][j] + a[i][k]*b[k][j];
  25
  26           asm volatile ("" ::: "memory");
  27         }
  28       asm volatile ("" ::: "memory");
  29     }
  30 }
  31
  32 extern void abort ();
  33
  34 static void __attribute__((noinline))
  35 init (int i)
  36 {
  37   for (int j = 0; j < M; j++)
  38     {
  39       a[i][j] = i;
  40       b[i][j] = j;
  41       c[i][j] = 0;
  42       d[i][j] = 0;
  43     }
  44 }
  45
  46 static int __attribute__((noinline))
  47 check (int i)
  48 {
  49   for (int j = 0; j < M; j++)
  50     if (c[i][j] != d[i][j])
  51       return 0;
  52
  53   return 1;
  54 }
  55
  56 int main (void)
  57 {
  58   for (int i = 0; i < M; ++i)
  59     init (i);
  60
  61   matrix_mul_1 (M);
  62   matrix_mul_2 (M);
  63
  64   for (int i = 0; i < M; ++i)
  65     if (!check (i))
  66       abort ();
  67
  68   return 0;
  69 }
  70
  71 /* { dg-final { scan-tree-dump-times "Loop_pair<outer:., inner:.> is interchanged" 1 "linterchange" } } */
  72 /* { dg-final { scan-tree-dump-times "Loop_pair<outer:., inner:.> is not interchanged" 1 "linterchange" } } */