From 5d2625f37f906b2187ea184cba9c2cc28f46d988 Mon Sep 17 00:00:00 2001 From: das Date: Sat, 7 Apr 2012 03:59:12 +0000 Subject: Fix a bug in remquo{,f,l}, in which the quotient didn't always have the correct sign when the remainder was 0. Fix a separate bug in remquo alone, in which the remainder and quotient were both off by a bit in certain cases involving subnormal remainders. The bugs affected all platforms except amd64 and i386, on which the routines are implemented in assembly. PR: 166463 Submitted by: Ilya Burylov MFC after: 2 weeks --- lib/msun/src/s_remquo.c | 7 ++++--- lib/msun/src/s_remquof.c | 3 ++- lib/msun/src/s_remquol.c | 3 ++- 3 files changed, 8 insertions(+), 5 deletions(-) (limited to 'lib') diff --git a/lib/msun/src/s_remquo.c b/lib/msun/src/s_remquo.c index a64277a..d811c69 100644 --- a/lib/msun/src/s_remquo.c +++ b/lib/msun/src/s_remquo.c @@ -51,7 +51,7 @@ remquo(double x, double y, int *quo) goto fixup; /* |x|<|y| return x or x-y */ } if(lx==ly) { - *quo = 1; + *quo = (sxy ? -1 : 1); return Zero[(u_int32_t)sx>>31]; /* |x|=|y| return x*0*/ } } @@ -114,6 +114,7 @@ remquo(double x, double y, int *quo) /* convert back to floating value and restore the sign */ if((hx|lx)==0) { /* return sign(x)*0 */ + q &= 0x7fffffff; *quo = (sxy ? -q : q); return Zero[(u_int32_t)sx>>31]; } @@ -129,9 +130,9 @@ remquo(double x, double y, int *quo) lx = (lx>>n)|((u_int32_t)hx<<(32-n)); hx >>= n; } else if (n<=31) { - lx = (hx<<(32-n))|(lx>>n); hx = sx; + lx = (hx<<(32-n))|(lx>>n); hx = 0; } else { - lx = hx>>(n-32); hx = sx; + lx = hx>>(n-32); hx = 0; } } fixup: diff --git a/lib/msun/src/s_remquof.c b/lib/msun/src/s_remquof.c index 3141642..f7b4c00 100644 --- a/lib/msun/src/s_remquof.c +++ b/lib/msun/src/s_remquof.c @@ -46,7 +46,7 @@ remquof(float x, float y, int *quo) q = 0; goto fixup; /* |x|<|y| return x or x-y */ } else if(hx==hy) { - *quo = 1; + *quo = (sxy ? -1 : 1); return Zero[(u_int32_t)sx>>31]; /* |x|=|y| return x*0*/ } @@ -88,6 +88,7 @@ remquof(float x, float y, int *quo) /* convert back to floating value and restore the sign */ if(hx==0) { /* return sign(x)*0 */ + q &= 0x7fffffff; *quo = (sxy ? -q : q); return Zero[(u_int32_t)sx>>31]; } diff --git a/lib/msun/src/s_remquol.c b/lib/msun/src/s_remquol.c index 9f5b578..712651c 100644 --- a/lib/msun/src/s_remquol.c +++ b/lib/msun/src/s_remquol.c @@ -96,7 +96,7 @@ remquol(long double x, long double y, int *quo) goto fixup; /* |x|<|y| return x or x-y */ } if(ux.bits.manh==uy.bits.manh && ux.bits.manl==uy.bits.manl) { - *quo = 1; + *quo = (sxy ? -1 : 1); return Zero[sx]; /* |x|=|y| return x*0*/ } } @@ -138,6 +138,7 @@ remquol(long double x, long double y, int *quo) /* convert back to floating value and restore the sign */ if((hx|lx)==0) { /* return sign(x)*0 */ + q &= 0x7fffffff; *quo = (sxy ? -q : q); return Zero[sx]; } -- cgit v1.1