Use __ldexp_exp() to simplify things and improve accuracy for x near

the overflow threshold.

4 files changed, 10 insertions, 27 deletions

diff --git a/lib/msun/src/e_cosh.c b/lib/msun/src/e_cosh.c
index 11e6590..a363695 100644
--- a/lib/msun/src/e_cosh.c
+++ b/lib/msun/src/e_cosh.c
@@ -45,7 +45,6 @@ __ieee754_cosh(double x)
 {
 	double t,w;
 	int32_t ix;
-	u_int32_t lx;
 
     /* High word of |x|. */
 	GET_HIGH_WORD(ix,x);
@@ -72,13 +71,8 @@ __ieee754_cosh(double x)
 	if (ix < 0x40862E42)  return half*__ieee754_exp(fabs(x));
 
     /* |x| in [log(maxdouble), overflowthresold] */
-	GET_LOW_WORD(lx,x);
-	if (ix<0x408633CE ||
-	      ((ix==0x408633ce)&&(lx<=(u_int32_t)0x8fb9f87d))) {
-	    w = __ieee754_exp(half*fabs(x));
-	    t = half*w;
-	    return t*w;
-	}
+	if (ix<=0x408633CE)
+	    return __ldexp_exp(fabs(x), -1);
 
     /* |x| > overflowthresold, cosh(x) overflow */
 	return huge*huge;
diff --git a/lib/msun/src/e_coshf.c b/lib/msun/src/e_coshf.c
index 4a1d499..95a0d6e 100644
--- a/lib/msun/src/e_coshf.c
+++ b/lib/msun/src/e_coshf.c
@@ -51,11 +51,8 @@ __ieee754_coshf(float x)
 	if (ix < 0x42b17217)  return half*__ieee754_expf(fabsf(x));
 
     /* |x| in [log(maxfloat), overflowthresold] */
-	if (ix<=0x42b2d4fc) {
-	    w = __ieee754_expf(half*fabsf(x));
-	    t = half*w;
-	    return t*w;
-	}
+	if (ix<=0x42b2d4fc)
+	    return __ldexp_expf(fabsf(x), -1);
 
     /* |x| > overflowthresold, cosh(x) overflow */
 	return huge*huge;
diff --git a/lib/msun/src/e_sinh.c b/lib/msun/src/e_sinh.c
index afb8e43..17442d0 100644
--- a/lib/msun/src/e_sinh.c
+++ b/lib/msun/src/e_sinh.c
@@ -40,9 +40,8 @@ static const double one = 1.0, shuge = 1.0e307;
 double
 __ieee754_sinh(double x)
 {
-	double t,w,h;
+	double t,h;
 	int32_t ix,jx;
-	u_int32_t lx;
 
     /* High word of |x|. */
 	GET_HIGH_WORD(jx,x);
@@ -66,12 +65,8 @@ __ieee754_sinh(double x)
 	if (ix < 0x40862E42)  return h*__ieee754_exp(fabs(x));
 
     /* |x| in [log(maxdouble), overflowthresold] */
-	GET_LOW_WORD(lx,x);
-	if (ix<0x408633CE || ((ix==0x408633ce)&&(lx<=(u_int32_t)0x8fb9f87d))) {
-	    w = __ieee754_exp(0.5*fabs(x));
-	    t = h*w;
-	    return t*w;
-	}
+	if (ix<=0x408633CE)
+	    return h*2.0*__ldexp_exp(fabs(x), -1);
 
     /* |x| > overflowthresold, sinh(x) overflow */
 	return x*shuge;
diff --git a/lib/msun/src/e_sinhf.c b/lib/msun/src/e_sinhf.c
index 0f96b2b..1be2dc3 100644
--- a/lib/msun/src/e_sinhf.c
+++ b/lib/msun/src/e_sinhf.c
@@ -24,7 +24,7 @@ static const float one = 1.0, shuge = 1.0e37;
 float
 __ieee754_sinhf(float x)
 {
-	float t,w,h;
+	float t,h;
 	int32_t ix,jx;
 
 	GET_FLOAT_WORD(jx,x);
@@ -48,11 +48,8 @@ __ieee754_sinhf(float x)
 	if (ix < 0x42b17217)  return h*__ieee754_expf(fabsf(x));
 
     /* |x| in [logf(maxfloat), overflowthresold] */
-	if (ix<=0x42b2d4fc) {
-	    w = __ieee754_expf((float)0.5*fabsf(x));
-	    t = h*w;
-	    return t*w;
-	}
+	if (ix<=0x42b2d4fc)
+	    return h*2.0F*__ldexp_expf(fabsf(x), -1);
 
     /* |x| > overflowthresold, sinh(x) overflow */
 	return x*shuge;