diff options
Diffstat (limited to 'gcc-4.9/gcc/testsuite/gcc.dg/tree-ssa/pr21559.c')
| -rw-r--r-- | gcc-4.9/gcc/testsuite/gcc.dg/tree-ssa/pr21559.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/gcc-4.9/gcc/testsuite/gcc.dg/tree-ssa/pr21559.c b/gcc-4.9/gcc/testsuite/gcc.dg/tree-ssa/pr21559.c new file mode 100644 index 000000000..6378d1aa7 --- /dev/null +++ b/gcc-4.9/gcc/testsuite/gcc.dg/tree-ssa/pr21559.c @@ -0,0 +1,44 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -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 "vrp1" } } */ + +/* 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" 3 "vrp1" } } */ + +/* { dg-final { cleanup-tree-dump "vrp1" } } */ + |