complex.c (csqrtq): NaN and INF fixes.

2012-10-31  Tobias Burnus  <burnus@net-b.de>
            Joseph Myers <joseph@codesourcery.com>
            David S. Miller <davem@davemloft.net>
            Ulrich Drepper <drepper@redhat.com>
            Marek Polacek <polacek@redhat.com>:
            Petr Baudis <pasky@suse.cz>

        * math/complex.c (csqrtq): NaN and INF fixes.
        * math/sqrtq.c (sqrt): NaN, INF and < 0 fixes.
        * math/expm1q.c (expm1q): Changes from GLIBC. Use expq for
        large parameters. Fix errno for boundary conditions.
        * math/finiteq.c (finiteq): Add comment.
        * math/fmaq.c (fmaq): Changes from GLIBC. Fix missing underflows
        and bad results for some subnormal results. Fix sign of inexact
        zero return. Fix sign of exact zero return.
        Ensure additions are not scheduled after fetestexcept.
        * math/jnq.c (jnq): Changes from GLIBC. Set up errno properly
        for ynq. Fix jnq precision.
        * math/nearbyintq.c (nearbyintq): Changes from GLIBC. Do not
        manipulate bits before adding and subtracting TWO112[sx].
        * math/rintq.c (rintq): Ditto.
        * math/scalbnq.c (scalbnq): Changes from GLIBC. Fix integer
        overflow.


Co-Authored-By: David S. Miller <davem@davemloft.net>
Co-Authored-By: Joseph Myers <joseph@codesourcery.com>
Co-Authored-By: Ulrich Drepper <drepper@redhat.com>

From-SVN: r193037

1 files changed, 13 insertions, 22 deletions

diff --git a/libquadmath/math/rintq.c b/libquadmath/math/rintq.c
index fe7a591..8a93fdb 100644
--- a/libquadmath/math/rintq.c
+++ b/libquadmath/math/rintq.c
@@ -13,6 +13,16 @@
  * ====================================================
  */
 
+/*
+ * rintq(x)
+ * Return x rounded to integral value according to the prevailing
+ * rounding mode.
+ * Method:
+ *	Using floating addition.
+ * Exception:
+ *	Inexact flag raised if x not equal to rintq(x).
+ */
+
 #include "quadmath-imp.h"
 
 static const __float128
@@ -25,42 +35,23 @@ __float128
 rintq (__float128 x)
 {
 	int64_t i0,j0,sx;
-	uint64_t i,i1;
+	uint64_t i1;
 	__float128 w,t;
 	GET_FLT128_WORDS64(i0,i1,x);
 	sx = (((uint64_t)i0)>>63);
 	j0 = ((i0>>48)&0x7fff)-0x3fff;
-	if(j0<48) {
+	if(j0<112) {
 	    if(j0<0) {
-		if(((i0&0x7fffffffffffffffLL)|i1)==0) return x;
-		i1 |= (i0&0x0000ffffffffffffLL);
-		i0 &= 0xffffe00000000000ULL;
-		i0 |= ((i1|-i1)>>16)&0x0000800000000000LL;
-		SET_FLT128_MSW64(x,i0);
 	        w = TWO112[sx]+x;
 	        t = w-TWO112[sx];
 		GET_FLT128_MSW64(i0,t);
 		SET_FLT128_MSW64(t,(i0&0x7fffffffffffffffLL)|(sx<<63));
 	        return t;
-	    } else {
-		i = (0x0000ffffffffffffLL)>>j0;
-		if(((i0&i)|i1)==0) return x; /* x is integral */
-		i>>=1;
-		if(((i0&i)|i1)!=0) {
-		    if(j0==47) i1 = 0x4000000000000000ULL; else
-		    i0 = (i0&(~i))|((0x0000200000000000LL)>>j0);
-		}
 	    }
-	} else if (j0>111) {
+	} else {
 	    if(j0==0x4000) return x+x;	/* inf or NaN */
 	    else return x;		/* x is integral */
-	} else {
-	    i = -1ULL>>(j0-48);
-	    if((i1&i)==0) return x;	/* x is integral */
-	    i>>=1;
-	    if((i1&i)!=0) i1 = (i1&(~i))|((0x4000000000000000LL)>>(j0-48));
 	}
-	SET_FLT128_WORDS64(x,i0,i1);
 	w = TWO112[sx]+x;
 	return w-TWO112[sx];
 }