add legacy scsi/scsi_ioctl.h header

[musl] / src / math / fmaf.c

diff --git a/src/math/fmaf.c b/src/math/fmaf.c
index 0dccf10..745ee39 100644 (file)
--- a/src/math/fmaf.c
+++ b/src/math/fmaf.c
@@ -37,6 +37,7 @@
  */
 float fmaf(float x, float y, float z)
 {
+       #pragma STDC FENV_ACCESS ON
        double xy, result;
        uint32_t hr, lr;
 
@@ -48,17 +49,27 @@ float fmaf(float x, float y, float z)
                (hr & 0x7ff00000) == 0x7ff00000 ||  /* NaN */
                result - xy == z ||                 /* exact */
                fegetround() != FE_TONEAREST)       /* not round-to-nearest */
-               return (result);
+       {
+               /*
+               TODO: underflow is not raised correctly, example in
+               downward rouding: fmaf(0x1p-120f, 0x1p-120f, 0x1p-149f)
+               */
+               z = result;
+               return z;
+       }
 
        /*
         * If result is inexact, and exactly halfway between two float values,
         * we need to adjust the low-order bit in the direction of the error.
         */
+#ifdef FE_TOWARDZERO
        fesetround(FE_TOWARDZERO);
+#endif
        volatile double vxy = xy;  /* XXX work around gcc CSE bug */
        double adjusted_result = vxy + z;
        fesetround(FE_TONEAREST);
        if (result == adjusted_result)
                SET_LOW_WORD(adjusted_result, lr + 1);
-       return (adjusted_result);
+       z = adjusted_result;
+       return z;
 }