PowerPC: fix hypot/hypof FP exceptions

This patch fixes hypot/hypotf spurious floating-point exceptions
generate by internal operations.

2 files changed, 14 insertions, 16 deletions

diff --git a/sysdeps/powerpc/fpu/e_hypot.c b/sysdeps/powerpc/fpu/e_hypot.c
index f23633946f..d8568d6e3f 100644
--- a/sysdeps/powerpc/fpu/e_hypot.c
+++ b/sysdeps/powerpc/fpu/e_hypot.c
@@ -26,6 +26,7 @@ static const double two600  = 4.149515568880993e+180;
 static const double two1022 = 4.49423283715579e+307;
 static const double twoM500 = 3.054936363499605e-151;
 static const double twoM600 = 2.4099198651028841e-181;
+static const double two60factor = 1.5592502418239997e+290;
 static const double pdnum   = 2.225073858507201e-308;
 
 /* __ieee754_hypot(x,y)
@@ -87,9 +88,20 @@ __ieee754_hypot (double x, double y)
       x = y;
       y = t;
     }
-  if (y == 0.0 || (x / y) > two60)
+  if (y == 0.0)
+    return x;
+  /* if y is higher enough, y * 2^60 might overflow. The tests if
+     y >= 1.7976931348623157e+308/2^60 (two60factor) and uses the
+     appropriate check to avoid the overflow exception generation.  */
+  if (y > two60factor)
     {
-      return x + y;
+      if ((x / y) > two60)
+	return x + y;
+    }
+  else
+    {
+      if (x > (y * two60))
+	return x + y;
     }
   if (x > two500)
     {
diff --git a/sysdeps/powerpc/fpu/e_hypotf.c b/sysdeps/powerpc/fpu/e_hypotf.c
index e97f0c35e3..93055afce5 100644
--- a/sysdeps/powerpc/fpu/e_hypotf.c
+++ b/sysdeps/powerpc/fpu/e_hypotf.c
@@ -69,22 +69,8 @@ static const float two30  = 1.0737418e09;
 float
 __ieee754_hypotf (float x, float y)
 {
-  x = fabsf (x);
-  y = fabsf (y);
-
   TEST_INF_NAN (x, y);
 
-  if (y > x)
-    {
-      float t = y;
-      y = x;
-      x = t;
-    }
-  if (y == 0.0 || (x / y) > two30)
-    {
-      return x + y;
-    }
-
   return __ieee754_sqrt ((double) x * x + (double) y * y);
 }
 strong_alias (__ieee754_hypotf, __hypotf_finite)