/* APPLE LOCAL file lno */ /* { dg-do compile } */ /* { dg-options "-O1 -floop-test -fdump-tree-lptest-details -fdump-tree-optimized" } */ void remove_me (void); int main(void) { int a; int b; int c; /* loop_1 runs 2 times. */ for (a = 22; a < 83; a+=1) /* a -> {22, +, 60}_1 */ { c = a; /* loop_2 runs exactly 6 times. */ for (b = 23; b < 50; b+=5) /* b -> {23, +, 5}_2 */ { ++a; } /* The following stmt exercises the value of B on the exit of the loop. In this case the value of B out of the loop is that of the evolution function of B applied to the number of iterations the inner loop_2 runs. Value (B) = {23, +, 5}_2 (6) = 53. */ /* At this point, the variable A has the evolution function: {{22, +, 6}_1, +, 1}_2. */ if (b != 53 || a != c + 6) remove_me (); a = a + b; /* At this point, the variable A has the evolution function: {{22, +, 59}_1, +, 1}_2. The evolution of the variable B in the loop_2 does not matter, and is not recorded in the evolution of A. The above statement is equivalent to: "a = a + 53", ie. the scalar value of B on exit of the loop_2. */ if (a != c + 59) remove_me (); /* And finally the a+=1 from the FOR_STMT produces the evolution function: {{22, +, 60}_1, +, 1}_2. */ } } /* { dg-final { scan-tree-dump-times "set_nb_iterations_in_loop = 2" 1 "lptest"} } */ /* { dg-final { scan-tree-dump-times "set_nb_iterations_in_loop = 6" 1 "lptest"} } */ /* { dg-final { scan-tree-dump-times "remove_me" 0 "optimized"} } */