[PATCH v4 17/21] math: Remove the SVID error handling from tgammaf

[Wilco Dijkstra]

Hi Adhemerval,

+      /* tgamma(x) overflows for:
+       * 0 <= x < 0x1p-128 whatever the rounding mode
+       * x = 0x1p-128 and rounding to nearest or away from zero
+	 (in which case the result is +Inf)
+       * -0x1p-128 <= x <= 0 whatever the rounding mode
+       */
+      if (fabsf (x) < 0x1p-128f ||
+	  (x == 0x1p-128f && r > 0x1.fffffep+127f) || x == -0x1p-128f)
+	errno = ERANGE; /* overflow */

It doesn't look like this could be added to the exception table, but
wouldn't it be simpler to check whether final result r is infinite?

if (is_inf (asuint (r)) return __math_oflowf (t >> 31);

-      return math_narrow_eval (x * 0x1p127f);
+      return __math_oflowf_value (math_narrow_eval (x * 0x1p127f));

Why not just use return __math_oflowf (0);

       if (x == 0.0f)
-	return 1.0f / x;
+	return __math_oflowf_value (1.0f / x);

Possibly still use __math_oflowf (t >> 31)?

-      return math_narrow_eval (0x1p-127f * sgn[k & 1]);
+      return __math_oflowf_value (math_narrow_eval (0x1p-127f * sgn[k & 1]));

Really? It's underflow, just use return __math_uflowf (k & 1);

+  if (fabsf (r) < 0x1p-126f)
+    errno = ERANGE; // underflow

That should be if (__glibc_unlikely (r == 0)) return __math_uflowf (rt >> 63);

Cheers,
Wilco