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)) matrix_mul_1(int n)8matrix_mul_1 (int n) 9 { 10 for (int k = 0; k < n; k++) 11 for (int j = 0; j < n; j++) 12 for (int i = 0; i < n; i++) 13 c[i][j] = c[i][j] + a[i][k]*b[k][j]; 14 } 15 16 void __attribute__((noinline)) matrix_mul_2(int n)17matrix_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)) init(int i)35init (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)) check(int i)47check (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 main(void)56int 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" 2 "linterchange" } } */ 72