PowerPC floating point little-endian [3 of 15]

http://sourceware.org/ml/libc-alpha/2013-08/msg00083.html

Further replacement of ieee854 macros and unions.  These files also
have some optimisations for comparison against 0.0L, infinity and nan.
Since the ABI specifies that the high double of an IBM long double
pair is the value rounded to double, a high double of 0.0 means the
low double must also be 0.0.  The ABI also says that infinity and
nan are encoded in the high double, with the low double unspecified.
This means that tests for 0.0L, +/-Infinity and +/-NaN need only check
the high double.

	* sysdeps/ieee754/ldbl-128ibm/e_atan2l.c (__ieee754_atan2l): Rewrite
	all uses of ieee854 long double macros and unions.  Simplify tests
	for long doubles that are fully specified by the high double.
	* sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c (__ieee754_gammal_r):
	Likewise.
	* sysdeps/ieee754/ldbl-128ibm/e_ilogbl.c (__ieee754_ilogbl): Likewise.
	Remove dead code too.
	* sysdeps/ieee754/ldbl-128ibm/e_jnl.c (__ieee754_jnl): Likewise.
	(__ieee754_ynl): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/e_log10l.c (__ieee754_log10l): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/e_logl.c (__ieee754_logl): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/e_powl.c (__ieee754_powl): Likewise.
	Remove dead code too.
	* sysdeps/ieee754/ldbl-128ibm/k_tanl.c (__kernel_tanl): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_expm1l.c (__expm1l): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_frexpl.c (__frexpl): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_isinf_nsl.c (__isinf_nsl): Likewise.
	Simplify.
	* sysdeps/ieee754/ldbl-128ibm/s_isinfl.c (___isinfl): Likewise.
	Simplify.
	* sysdeps/ieee754/ldbl-128ibm/s_log1pl.c (__log1pl): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_modfl.c (__modfl): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c (__nextafterl): Likewise.
	Comment on variable precision.
	* sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c (__nexttoward): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c (__nexttowardf):
	Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_remquol.c (__remquol): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_scalblnl.c (__scalblnl): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_scalbnl.c (__scalbnl): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_tanhl.c (__tanhl): Likewise.
	* sysdeps/powerpc/fpu/libm-test-ulps: Adjust tan_towardzero ulps.

1 files changed, 16 insertions, 18 deletions

diff --git a/sysdeps/ieee754/ldbl-128ibm/k_tanl.c b/sysdeps/ieee754/ldbl-128ibm/k_tanl.c
index 1f6bad2..bcf8b5e 100644
--- a/sysdeps/ieee754/ldbl-128ibm/k_tanl.c
+++ b/sysdeps/ieee754/ldbl-128ibm/k_tanl.c
@@ -85,17 +85,17 @@ long double
 __kernel_tanl (long double x, long double y, int iy)
 {
   long double z, r, v, w, s;
-  int32_t ix, sign;
-  ieee854_long_double_shape_type u, u1;
+  int32_t ix, sign, hx, lx;
+  double xhi;
 
-  u.value = x;
-  ix = u.parts32.w0 & 0x7fffffff;
+  xhi = ldbl_high (x);
+  EXTRACT_WORDS (hx, lx, xhi);
+  ix = hx & 0x7fffffff;
   if (ix < 0x3c600000)		/* x < 2**-57 */
     {
-      if ((int) x == 0)
-	{			/* generate inexact */
-	  if ((ix | u.parts32.w1 | (u.parts32.w2 & 0x7fffffff) | u.parts32.w3
-	       | (iy + 1)) == 0)
+      if ((int) x == 0)		/* generate inexact */
+	{
+	  if ((ix | lx | (iy + 1)) == 0)
 	    return one / fabs (x);
 	  else
 	    return (iy == 1) ? x : -one / x;
@@ -103,7 +103,7 @@ __kernel_tanl (long double x, long double y, int iy)
     }
   if (ix >= 0x3fe59420) /* |x| >= 0.6743316650390625 */
     {
-      if ((u.parts32.w0 & 0x80000000) != 0)
+      if ((hx & 0x80000000) != 0)
 	{
 	  x = -x;
 	  y = -y;
@@ -139,15 +139,13 @@ __kernel_tanl (long double x, long double y, int iy)
     {				/* if allow error up to 2 ulp,
 				   simply return -1.0/(x+r) here */
       /*  compute -1.0/(x+r) accurately */
-      u1.value = w;
-      u1.parts32.w2 = 0;
-      u1.parts32.w3 = 0;
-      v = r - (u1.value - x);		/* u1+v = r+x */
+      long double u1, z1;
+
+      u1 = ldbl_high (w);
+      v = r - (u1 - x);		/* u1+v = r+x */
       z = -1.0 / w;
-      u.value = z;
-      u.parts32.w2 = 0;
-      u.parts32.w3 = 0;
-      s = 1.0 + u.value * u1.value;
-      return u.value + z * (s + u.value * v);
+      z1 = ldbl_high (z);
+      s = 1.0 + z1 * u1;
+      return z1 + z * (s + z1 * v);
     }
 }