Re: [PATCH] Update sparc ULPs.

[David Miller <davem at davemloft dot net>]

Ok I adjusted my patch with your feedback in mind.  See at the
end of this email.

But I had some trouble in my crash course of trying to use MPFR
to generate test cases.  For example I tried to use:

--------------------
#include <stdio.h>
#include <mpfr.h>

int main(void)
{
	char str[64];
	mpfr_t x, y;
	int i;

	mpfr_init2 (x, 300);
	mpfr_init2 (y, 300);

	for (i = 10; i < 120; i+= 10) {
		sprintf(str, "1e-%d", i);
		mpfr_set_str (x, str, 10, MPFR_RNDN);
		mpfr_y0 (y, x, MPFR_RNDN);
		mpfr_printf ("y0(%d): %Ra\n", i, y);
	}
	return 0;
}
--------------------

Which, for example, generates:

y0(10): -0xe.bb862fbb05c0be5781f1ba338863546295571dbc980dae4ae815d43997f6c76ca47758debp+0

Which I transformed into testcase:

====================
  TEST_f_f (y0, 0x1p-10, -0xe.bb862fbb05c0be5781f1ba338863546295571dbc980dae4ae815d43997f6c76ca47758debp+0);
====================

but that doesn't seem to be right:

====================
testing float (without inline functions)
Failure: Test: y0 (0x1p-10) == -0xe.bb862fbb05c0be5781f1ba338863546295571dbc980dae4ae815d43997f6c76ca47758debp+0
Result:
 is:         -4.48651504516601562500e+00  -0x1.1f231000000000000000p+2
 should be:  -1.47325162887573242188e+01  -0x1.d770c600000000000000p+3
 difference:  1.02460012435913085938e+01   0x1.47df3e00000000000000p+3
 ulp       :  10743711.0000
 max.ulp   :  0.0000
Maximal error of `y0'
 is      : 10743711 ulp
 accepted: 1 ulp
====================

It's obvious I've never done this before :-)

diff --git a/sysdeps/ieee754/flt-32/e_j0f.c b/sysdeps/ieee754/flt-32/e_j0f.c
index 0729cd0..8a8801d 100644
--- a/sysdeps/ieee754/flt-32/e_j0f.c
+++ b/sysdeps/ieee754/flt-32/e_j0f.c
@@ -138,7 +138,7 @@ __ieee754_y0f(float x)
 		}
 		return z;
 	}
-	if(ix<=0x32000000) {	/* x < 2**-27 */
+	if(ix<=0x36800000) {	/* x < 2**-18 */
 	    return(u00 + tpi*__ieee754_logf(x));
 	}
 	z = x*x;
diff --git a/sysdeps/ieee754/flt-32/e_j1f.c b/sysdeps/ieee754/flt-32/e_j1f.c
index 30b7d8e..7c2b649 100644
--- a/sysdeps/ieee754/flt-32/e_j1f.c
+++ b/sysdeps/ieee754/flt-32/e_j1f.c
@@ -67,7 +67,7 @@ __ieee754_j1f(float x)
 		if(hx<0) return -z;
 		else	 return  z;
 	}
-	if(__builtin_expect(ix<0x32000000, 0)) {	/* |x|<2**-27 */
+	if(__builtin_expect(ix<0x36800000, 0)) {	/* |x|<2**-18 */
 	    if(huge+x>one) return (float)0.5*x;/* inexact if x!=0 necessary */
 	}
 	z = x*x;
diff --git a/sysdeps/ieee754/ldbl-128/e_j0l.c b/sysdeps/ieee754/ldbl-128/e_j0l.c
index 112a8f3..fb98ea7 100644
--- a/sysdeps/ieee754/ldbl-128/e_j0l.c
+++ b/sysdeps/ieee754/ldbl-128/e_j0l.c
@@ -831,6 +831,8 @@ long double
       return -HUGE_VALL + x;
     }
   xx = fabsl (x);
+  if (xx <= 0x1p-57)
+    return TWOOPI * __ieee754_logl (x);
   if (xx <= 2.0L)
     {
       /* 0 <= x <= 2 */
diff --git a/sysdeps/ieee754/ldbl-128/e_j1l.c b/sysdeps/ieee754/ldbl-128/e_j1l.c
index 1f62bd0..f16343b 100644
--- a/sysdeps/ieee754/ldbl-128/e_j1l.c
+++ b/sysdeps/ieee754/ldbl-128/e_j1l.c
@@ -838,6 +838,8 @@ __ieee754_y1l (long double x)
       return -HUGE_VALL + x;
     }
   xx = fabsl (x);
+  if (xx <= 0x1p-114)
+    return -TWOOPI / x;
   if (xx <= 2.0L)
     {
       /* 0 <= x <= 2 */