This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
Tru64: S_mulexp10 overflow help.
authorJarkko Hietaniemi <jhi@iki.fi>
Sun, 12 Oct 2014 21:43:48 +0000 (17:43 -0400)
committerJarkko Hietaniemi <jhi@iki.fi>
Mon, 13 Oct 2014 01:58:07 +0000 (21:58 -0400)
numeric.c

index 75d348d..171f593 100644 (file)
--- a/numeric.c
+++ b/numeric.c
@@ -1033,10 +1033,21 @@ S_mulexp10(NV value, I32 exponent)
             return value;
 #endif
     }
+#if defined(__osf__)
+    /* Even with cc -ieee + ieee_set_fp_control(IEEE_TRAP_ENABLE_INV)
+     * Tru64 fp behavior on inf/nan is somewhat broken. Another way
+     * to do this would be ieee_set_fp_control(IEEE_TRAP_ENABLE_OVF)
+     * but that breaks another set of infnan.t tests. */
+#  define FP_OVERFLOWS_TO_ZERO
+#endif
     for (bit = 1; exponent; bit <<= 1) {
        if (exponent & bit) {
            exponent ^= bit;
            result *= power;
+#ifdef FP_OVERFLOWS_TO_ZERO
+            if (result == 0)
+                return value < 0 ? -NV_INF : NV_INF;
+#endif
            /* Floating point exceptions are supposed to be turned off,
             *  but if we're obviously done, don't risk another iteration.  
             */