* sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c (nextafterl): Remove
authorjakub <jakub>
Sat, 7 Jul 2007 16:16:55 +0000 (16:16 +0000)
committerjakub <jakub>
Sat, 7 Jul 2007 16:16:55 +0000 (16:16 +0000)
unused ily variable.  Fix nextafterl on +-__LDBL_MAX__ and +-Inf.
Remove unreachable code at the end.

* sysdeps/ieee754/ldbl-128ibm/s_fpclassifyl.c: Correct description of
ldbl-128ibm in comment.
(fpclassifyl): Correct classification of denormals.
* sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c (nextafterl): Correct
return value for MIN denormal. Rewrite using long double math too
correctly handle denormals and canonicalize the results.

ChangeLog
sysdeps/ieee754/ldbl-128ibm/s_fpclassifyl.c
sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c

index 6b20f8f..5cbb700 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,18 @@
+2007-06-04  Jakub Jelinek  <jakub@redhat.com>
+
+       * sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c (nextafterl): Remove
+       unused ily variable.  Fix nextafterl on +-__LDBL_MAX__ and +-Inf.
+       Remove unreachable code at the end.
+
+2007-06-01  Steven Munroe  <sjmunroe@us.ibm.com>
+
+       * sysdeps/ieee754/ldbl-128ibm/s_fpclassifyl.c: Correct description of
+       ldbl-128ibm in comment.
+       (fpclassifyl): Correct classification of denormals.
+       * sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c (nextafterl): Correct
+       return value for MIN denormal. Rewrite using long double math too
+       correctly handle denormals and canonicalize the results.
+
 2007-05-29  Ulrich Drepper  <drepper@redhat.com>
 
        * nscd/nscd_helper.c (get_mapping): Handle short replies instead
index 3ca178a..b9b8f42 100644 (file)
    * -NaN      fffn nnnn nnnn nnnn xxxx xxxx xxxx xxxx
    * +Inf      7ff0 0000 0000 0000 xxxx xxxx xxxx xxxx
    * -Inf      fff0 0000 0000 0000 xxxx xxxx xxxx xxxx
-   * +0                0000 0000 0000 0000
-   * -0                8000 0000 0000 0000
-   * +normal   001n nnnn nnnn nnnn (smallest)
-   * -normal   801n nnnn nnnn nnnn (smallest)
-   * +normal   7fen nnnn nnnn nnnn (largest)
-   * -normal   ffen nnnn nnnn nnnn (largest)
-   * +denorm   000n nnnn nnnn nnnn
-   * -denorm   800n nnnn nnnn nnnn
+   * +0                0000 0000 0000 0000 xxxx xxxx xxxx xxxx
+   * -0                8000 0000 0000 0000 xxxx xxxx xxxx xxxx
+   * +normal   0360 0000 0000 0000 0000 0000 0000 0000 (smallest)
+   * -normal   8360 0000 0000 0000 0000 0000 0000 0000 (smallest)
+   * +normal   7fef ffff ffff ffff 7c8f ffff ffff fffe (largest)
+   * +normal   ffef ffff ffff ffff fc8f ffff ffff fffe (largest)
+   * +denorm   0360 0000 0000 0000 8000 0000 0000 0001 (largest)
+   * -denorm   8360 0000 0000 0000 0000 0000 0000 0001 (largest)
+   * +denorm   000n nnnn nnnn nnnn xxxx xxxx xxxx xxxx
+   * -denorm   800n nnnn nnnn nnnn xxxx xxxx xxxx xxxx
    */
 
 int
@@ -59,12 +61,23 @@ ___fpclassifyl (long double x)
       /* +/-zero or +/- normal or +/- denormal */
       if (hx & 0x7fffffffffffffffULL) {
          /* +/- normal or +/- denormal */
-         if ((hx & 0x7ff0000000000000ULL) >= 0x0360000000000000ULL) {
+         if ((hx & 0x7ff0000000000000ULL) > 0x0360000000000000ULL) {
              /* +/- normal */
              retval = FP_NORMAL;
          } else {
-             /* +/- denormal */
-             retval = FP_SUBNORMAL;
+             if ((hx & 0x7ff0000000000000ULL) == 0x0360000000000000ULL) {
+                 if ((lx & 0x7fffffffffffffff) /* lower is non-zero */
+                 && ((lx^hx) & 0x8000000000000000ULL)) { /* and sign differs */
+                     /* +/- denormal */
+                     retval = FP_SUBNORMAL;
+                 } else {
+                     /* +/- normal */
+                     retval = FP_NORMAL;
+                 }
+             } else {
+                 /* +/- denormal */
+                 retval = FP_SUBNORMAL;
+             }
          }
       } else {
          /* +/- zero */
index 4f8aa7d..39d0e6a 100644 (file)
@@ -35,7 +35,7 @@ static char rcsid[] = "$NetBSD: $";
        long double x,y;
 #endif
 {
-       int64_t hx,hy,ihx,ihy,ilx,ily;
+       int64_t hx,hy,ihx,ihy,ilx;
        u_int64_t lx,ly;
 
        GET_LDOUBLE_WORDS64(hx,lx,x);
@@ -43,7 +43,6 @@ static char rcsid[] = "$NetBSD: $";
        ihx = hx&0x7fffffffffffffffLL;          /* |hx| */
        ilx = lx&0x7fffffffffffffffLL;          /* |lx| */
        ihy = hy&0x7fffffffffffffffLL;          /* |hy| */
-       ily = ly&0x7fffffffffffffffLL;          /* |ly| */
 
        if((((ihx&0x7ff0000000000000LL)==0x7ff0000000000000LL)&&
            ((ihx&0x000fffffffffffffLL)!=0)) ||   /* x is nan */
@@ -54,54 +53,66 @@ static char rcsid[] = "$NetBSD: $";
            return y;           /* x=y, return y */
        if(ihx == 0 && ilx == 0) {                      /* x == 0 */
            long double u;
-           SET_LDOUBLE_WORDS64(x,hy&0x8000000000000000ULL,1);/* return +-minsubnormal */
-           u = math_opt_barrier (u);
+           hy = (hy & 0x8000000000000000ULL) | 1;
+           SET_LDOUBLE_WORDS64(x,hy,0ULL);/* return +-minsubnormal */
+           u = math_opt_barrier (x);
            u = u * u;
            math_force_eval (u);                /* raise underflow flag */
            return x;
        }
-       if(ihx>=0) {                    /* x > 0 */
-           if(ihx>ihy||((ihx==ihy)&&(ilx>ily))) {      /* x > y, x -= ulp */
-
-               if(ilx==0)
-                   hx--;
-               else
-                   lx--;
-           } else {                            /* x < y, x += ulp */
-               if((hx==0x7fefffffffffffffLL)&&(lx==0x7c8ffffffffffffeLL))
-                 {
-                   SET_LDOUBLE_WORDS64(x,0x7ff0000000000000,0x8000000000000000);
-                   return x;
-                 }
-               else if((hx==0xffefffffffffffffLL)&&(lx==0xfc8ffffffffffffeLL))
-                 {
-                   SET_LDOUBLE_WORDS64(x,0xfff0000000000000,0x8000000000000000);
-                   return x;
-                 }
-               else if((lx&0x7fffffffffffffff)==0) hx++;
-               else
-                 lx++;
+       
+       long double u;
+       if(x > y) {     /* x > y, x -= ulp */
+           if((hx==0xffefffffffffffffLL)&&(lx==0xfc8ffffffffffffeLL))
+             return x+x;       /* overflow, return -inf */
+           if (hx >= 0x7ff0000000000000LL) {
+             SET_LDOUBLE_WORDS64(u,0x7fefffffffffffffLL,0x7c8ffffffffffffeLL);
+             return u;
            }
-       } else {                                /* x < 0 */
-           if(ihy>=0||ihx>ihy||((ihx==ihy)&&(ilx>ily))){/* x < y, x -= ulp */
-               if((lx&0x7fffffffffffffff)==0)
-                   hx--;
-               else
-                   lx--;
-           } else {                            /* x > y, x += ulp */
-               if((lx&0x7fffffffffffffff)==0) hx++;
-               else
-                 lx++;
+           if(ihx <= 0x0360000000000000LL) {  /* x <= LDBL_MIN */
+             u = math_opt_barrier (x);
+             x -= __LDBL_DENORM_MIN__;
+             if (ihx < 0x0360000000000000LL
+                 || (hx > 0 && (int64_t) lx <= 0)
+                 || (hx < 0 && (int64_t) lx > 1)) {
+               u = u * u;
+               math_force_eval (u);            /* raise underflow flag */
+             }
+             return x;
            }
+           if (ihx < 0x06a0000000000000LL) { /* ulp will denormal */
+             SET_LDOUBLE_WORDS64(u,(hx&0x7ff0000000000000LL),0ULL);
+             u *= 0x1.0000000000000p-105L;
+           } else
+             SET_LDOUBLE_WORDS64(u,(hx&0x7ff0000000000000LL)-0x0690000000000000LL,0ULL);
+           return x - u;
+       } else {                                /* x < y, x += ulp */
+           if((hx==0x7fefffffffffffffLL)&&(lx==0x7c8ffffffffffffeLL))
+             return x+x;       /* overflow, return +inf */
+           if ((u_int64_t) hx >= 0xfff0000000000000ULL) {
+             SET_LDOUBLE_WORDS64(u,0xffefffffffffffffLL,0xfc8ffffffffffffeLL);
+             return u;
+           }
+           if(ihx <= 0x0360000000000000LL) {  /* x <= LDBL_MIN */
+             u = math_opt_barrier (x);
+             x += __LDBL_DENORM_MIN__;
+             if (ihx < 0x0360000000000000LL
+                 || (hx > 0 && (int64_t) lx < 0 && lx != 0x8000000000000001LL)
+                 || (hx < 0 && (int64_t) lx >= 0)) {
+               u = u * u;
+               math_force_eval (u);            /* raise underflow flag */
+             }
+             if (x == 0.0L)    /* handle negative __LDBL_DENORM_MIN__ case */
+               x = -0.0L;
+             return x;
+           }
+           if (ihx < 0x06a0000000000000LL) { /* ulp will denormal */
+             SET_LDOUBLE_WORDS64(u,(hx&0x7ff0000000000000LL),0ULL);
+             u *= 0x1.0000000000000p-105L;
+           } else
+             SET_LDOUBLE_WORDS64(u,(hx&0x7ff0000000000000LL)-0x0690000000000000LL,0ULL);
+           return x + u;
        }
-       hy = hx&0x7ff0000000000000LL;
-       if(hy==0x7ff0000000000000LL) return x+x;/* overflow  */
-       if(hy==0) {
-           long double u = x * x;              /* underflow */
-           math_force_eval (u);                /* raise underflow flag */
-       }
-       SET_LDOUBLE_WORDS64(x,hx,lx);
-       return x;
 }
 strong_alias (__nextafterl, __nexttowardl)
 long_double_symbol (libm, __nextafterl, nextafterl);