/* { dg-do compile } */ /* { dg-options "-O2 -fdump-tree-vrp-details -fdump-tree-vrp1-details" } */ static int blocksize = 4096; int bar (int); void foo (void) { int toread; int bytes; static char eof_reached = 0; toread = blocksize; bytes = 1; while (toread != 0) { bytes = bar (toread); if (bytes <= 0) { if (bytes < 0) continue; break; } toread -= bytes; } if (bytes == 0) eof_reached = 1; } /* First, we should simplify the bits < 0 test within the loop. */ /* { dg-final { scan-tree-dump-times "Simplified relational" 1 "vrp" } } */ /* Second, we should thread the edge out of the loop via the break statement. We also realize that the final bytes == 0 test is useless, and thread over it. We also know that toread != 0 is useless when entering while loop and thread over it. */ /* { dg-final { scan-tree-dump-times "Threaded jump" 1 "vrp1" } } */ /* { dg-final { cleanup-tree-dump "vrp" } } */ /* { dg-final { cleanup-tree-dump "vrp1" } } */