diff options
| -rw-r--r-- | ChangeLog | 5 | ||||
| -rw-r--r-- | string/tst-xbzero-opt.c | 15 |
2 files changed, 20 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog index d88a7987f2..3e25bd7a18 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2018-07-26 Stefan Liebler <stli@linux.ibm.com> + + * string/tst-xbzero-opt.c (use_test_buffer): New function. + (prepare_test_buffer): Call use_test_buffer as compiler barrier. + 2018-07-26 Florian Weimer <fweimer@redhat.com> * htl/lockfile.c (flockfile, funlockfile, ftrylockfile): Use weak diff --git a/string/tst-xbzero-opt.c b/string/tst-xbzero-opt.c index aab4a7f715..898345b288 100644 --- a/string/tst-xbzero-opt.c +++ b/string/tst-xbzero-opt.c @@ -97,6 +97,17 @@ static const unsigned char test_pattern[16] = static ucontext_t uc_main, uc_co; +static __attribute__ ((noinline, noclone)) int +use_test_buffer (unsigned char *buf) +{ + unsigned int sum = 0; + + for (unsigned int i = 0; i < PATTERN_REPS; i++) + sum += buf[i * PATTERN_SIZE]; + + return (sum == 2 * PATTERN_REPS) ? 0 : 1; +} + /* Always check the test buffer immediately after filling it; this makes externally visible side effects depend on the buffer existing and having been filled in. */ @@ -116,6 +127,10 @@ prepare_test_buffer (unsigned char *buf) if (swapcontext (&uc_co, &uc_main)) abort (); + + /* Force the compiler to really copy the pattern to buf. */ + if (use_test_buffer (buf)) + abort (); } static void |