Mercurial > hg > CbC > CbC_gcc
view gcc/testsuite/gcc.dg/tree-ssa/pr19210-1.c @ 131:84e7813d76e9
gcc-8.2
author | mir3636 |
---|---|
date | Thu, 25 Oct 2018 07:37:49 +0900 |
parents | 04ced10e8804 |
children |
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/* { dg-do compile } */ /* { dg-options "-O2 -fopt-info-loop-missed" } */ extern void g(void); void f (unsigned n) { unsigned k; for(k = 0;k <= n;k++) /* { dg-missed "missed loop optimization: niters analysis .*" } */ g(); for(k = 0;k <= n;k += 4) /* { dg-missed "missed loop optimization: niters analysis .*" } */ g(); /* We used to get warning for this loop. However, since then # of iterations analysis improved, and we can now prove that this loop does not verflow. This is because the only case when it would overflow is if n = ~0 (since ~0 is divisible by 5), and this cannot be the case, since when we got here, the previous loop exited, thus there exists k > n. */ for(k = 5;k <= n;k += 5) g(); /* So we need the following loop, instead. */ for(k = 4;k <= n;k += 5) /* { dg-missed "missed loop optimization: niters analysis .*" } */ g(); for(k = 15;k >= n;k--) /* { dg-missed "missed loop optimization: niters analysis .*" } */ g(); }