remainder, remainderf, remainderl: Fix computation for large quotients.

[gnulib.git] / lib / remainderf.c

diff --git a/lib/remainderf.c b/lib/remainderf.c
index d75cf2d..93fd1a3 100644 (file)
--- a/lib/remainderf.c
+++ b/lib/remainderf.c
@@ -19,32 +19,17 @@
 /* Specification.  */
 #include <math.h>
 
+#if HAVE_REMAINDER
+
 float
 remainderf (float x, float y)
 {
-#if HAVE_REMAINDER
   return (float) remainder ((double) x, (double) y);
+}
+
 #else
-  float q = - roundf (x / y);
-  float r = fmaf (q, y, x); /* = x + q * y, computed in one step */
-  /* Correct possible rounding errors in the quotient x / y.  */
-  float half_y = 0.5L * y;
-  if (y >= 0)
-    {
-      /* Expect -y/2 <= r <= y/2.  */
-      if (r > half_y)
-        q -= 1, r = fmaf (q, y, x);
-      else if (r < - half_y)
-        q += 1, r = fmaf (q, y, x);
-    }
-  else
-    {
-      /* Expect y/2 <= r <= -y/2.  */
-      if (r > - half_y)
-        q += 1, r = fmaf (q, y, x);
-      else if (r < half_y)
-        q -= 1, r = fmaf (q, y, x);
-    }
-  return r;
+
+# define USE_FLOAT
+# include "remainder.c"
+
 #endif
-}