commit b88281024579d5f207d15d1a2cc54c113f8a2bde Author: Nick Mathewson nickm@torproject.org Date: Wed May 15 08:28:25 2019 -0400
In coverage builds, use branch-free timeradd() and timersub()
The ordinary definitions of timeradd() and timersub() contain a branch. However, in coverage builds, this means that we get spurious complaints about partially covered basic blocks, in a way that makes our coverage determinism harder to check. --- src/lib/wallclock/timeval.h | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+)
diff --git a/src/lib/wallclock/timeval.h b/src/lib/wallclock/timeval.h index 4967e939b..33076adc8 100644 --- a/src/lib/wallclock/timeval.h +++ b/src/lib/wallclock/timeval.h @@ -20,6 +20,27 @@ #include <sys/time.h> #endif
+#ifdef TOR_COVERAGE +/* For coverage builds, we use a slower definition of these macros without + * branches, to make coverage consistent. */ +#undef timeradd +#undef timersub +#define timeradd(tv1,tv2,tvout) \ + do { \ + (tvout)->tv_sec = (tv1)->tv_sec + (tv2)->tv_sec; \ + (tvout)->tv_usec = (tv1)->tv_usec + (tv2)->tv_usec; \ + (tvout)->tv_sec += (tvout)->tv_usec / 1000000; \ + (tvout)->tv_usec %= 1000000; \ + } while (0) +#define timersub(tv1,tv2,tvout) \ + do { \ + (tvout)->tv_sec = (tv1)->tv_sec - (tv2)->tv_sec - 1; \ + (tvout)->tv_usec = (tv1)->tv_usec - (tv2)->tv_usec + 1000000; \ + (tvout)->tv_sec += (tvout)->tv_usec / 1000000; \ + (tvout)->tv_usec %= 1000000; \ + } while (0) +#endif + #ifndef timeradd /** Replacement for timeradd on platforms that do not have it: sets tvout to * the sum of tv1 and tv2. */