[newlib-cygwin] Fix hypotf missing mask in hi+lo decomposition

[newlib-cygwin] Fix hypotf missing mask in hi+lo decomposition

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=6b0c1e7cc8e4b0568f00c8444fff8da67688add3

commit 6b0c1e7cc8e4b0568f00c8444fff8da67688add3
Author: Fabian Schriever <fabian.schriever@gtd-gmbh.de>
Date:   Thu Mar 19 16:34:08 2020 +0100

    Fix hypotf missing mask in hi+lo decomposition
    
    Add the missing mask for the decomposition of hi+lo which caused some
    errors of 1-2 ULP.
    
    This change is taken over from FreeBSD:
    https://github.com/freebsd/freebsd/commit/95436ce20dab5a34ba46373410b96411b1734578
    
    Additionally I've removed some variable assignments which were never
    read before being overwritten again in the next 2 lines.

Diff:
---
 newlib/libm/math/ef_hypot.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/newlib/libm/math/ef_hypot.c b/newlib/libm/math/ef_hypot.c
index 9368eb41c..a70c92b88 100644
--- a/newlib/libm/math/ef_hypot.c
+++ b/newlib/libm/math/ef_hypot.c
@@ -29,7 +29,7 @@
 	ha &= 0x7fffffffL;
 	GET_FLOAT_WORD(hb,y);
 	hb &= 0x7fffffffL;
-	if(hb > ha) {a=y;b=x;j=ha; ha=hb;hb=j;} else {a=x;b=y;}
+	if(hb > ha) { j = ha; ha = hb; hb = j; }
 	SET_FLOAT_WORD(a,ha);	/* a <- |a| */
 	SET_FLOAT_WORD(b,hb);	/* b <- |b| */
 	if((ha-hb)>0xf000000L) {return a+b;} /* x/y > 2**30 */
@@ -72,7 +72,7 @@
 	    a  = a+a;
 	    SET_FLOAT_WORD(y1,hb&0xfffff000L);
 	    y2 = b - y1;
-	    SET_FLOAT_WORD(t1,ha+0x00800000L);
+	    SET_FLOAT_WORD(t1,(ha+0x00800000L)&0xfffff000UL);
 	    t2 = a - t1;
 	    w  = __ieee754_sqrtf(t1*y1-(w*(-w)-(t1*y2+t2*b)));
 	}