On Thu, Nov 13, 2014 at 01:33:07PM -0800, Teresa Johnson wrote:
> > Supposedly the printfs should have been removed and the #include <cstdio>
> > isn't needed then either. No need to clutter the test output and log files.
> > On the other side, tests should abort (); or __builtin_abort (); on failure,
> > not just return non-zero.
>
> Ok, sounds good. Here is the new patch. Confirmed that the test case
> passes with the fix, aborts without it.
>
> If this looks good I will also update the trunk version of the test.
LGTM, thanks.
Please commit also the tree-ssa-strlen.c change to the trunk, it will not
hurt.
> 2014-11-13 Teresa Johnson <tejohn...@google.com>
>
> gcc:
> PR tree-optimization/63841
> * tree-ssa-strlen.c (strlen_optimize_stmt): Ignore clobbers.
>
> 2014-11-13 Teresa Johnson <tejohn...@google.com>
>
> gcc/testsuite:
> PR tree-optimization/63841
> * testsuite/g++.dg/tree-ssa/pr63841.C: New test.
>
> Index: tree-ssa-strlen.c
> ===================================================================
> --- tree-ssa-strlen.c (revision 217503)
> +++ tree-ssa-strlen.c (working copy)
> @@ -1856,7 +1856,7 @@ strlen_optimize_stmt (gimple_stmt_iterator *gsi)
> break;
> }
> }
> - else if (is_gimple_assign (stmt))
> + else if (is_gimple_assign (stmt) && !gimple_clobber_p (stmt))
> {
> tree lhs = gimple_assign_lhs (stmt);
>
> Index: testsuite/g++.dg/tree-ssa/pr63841.C
> ===================================================================
> --- testsuite/g++.dg/tree-ssa/pr63841.C (revision 0)
> +++ testsuite/g++.dg/tree-ssa/pr63841.C (working copy)
> @@ -0,0 +1,35 @@
> +/* { dg-do run } */
> +/* { dg-options "-O2" } */
> +
> +#include <string>
> +
> +std::string __attribute__ ((noinline)) comp_test_write() {
> + std::string data;
> +
> + for (int i = 0; i < 2; ++i) {
> + char b = 1 >> (i * 8);
> + data.append(&b, 1);
> + }
> +
> + return data;
> +}
> +
> +std::string __attribute__ ((noinline)) comp_test_write_good() {
> + std::string data;
> +
> + char b;
> + for (int i = 0; i < 2; ++i) {
> + b = 1 >> (i * 8);
> + data.append(&b, 1);
> + }
> +
> + return data;
> +}
> +
> +int main() {
> + std::string good = comp_test_write_good();
> + std::string bad = comp_test_write();
> +
> + if (good != bad)
> + __builtin_abort ();
> +}
Jakub
