msvcrt: Import atanf implementation from musl.

configure

@@ -19617,7 +19617,6 @@ fi
 
 for ac_func in \
 	atanh \
-	atanhf \
 	exp2 \
 	exp2f \
 	expm1 \

configure.ac

@@ -2657,7 +2657,6 @@ fi
 
 AC_CHECK_FUNCS(\
 	atanh \
-	atanhf \
 	exp2 \
 	exp2f \
 	expm1 \

dlls/msvcrt/math.c

@@ -6687,21 +6687,37 @@ double CDECL atanh(double x)
 
 /*********************************************************************
  *      atanhf (MSVCR120.@)
+ *
+ * Copied from musl: src/math/atanhf.c
  */
 float CDECL atanhf(float x)
 {
-    float ret;
+    UINT32 ux = *(UINT32*)&x;
+    int s = ux >> 31;
 
-    if (x > 1 || x < -1) {
+    /* |x| */
+    ux &= 0x7fffffff;
+    x = *(float*)&ux;
+
+    if (x > 1) {
         *_errno() = EDOM;
         feraiseexcept(FE_INVALID);
         return NAN;
     }
 
-    ret = unix_funcs->atanh( x );
-
-    if (!isfinite(ret)) *_errno() = ERANGE;
-    return ret;
+    if (ux < 0x3f800000 - (1 << 23)) {
+        if (ux < 0x3f800000 - (32 << 23)) {
+            fp_barrierf(x + 0x1p120f);
+            if (ux < (1 << 23)) /* handle underflow */
+                fp_barrierf(x * x);
+        } else { /* |x| < 0.5, up to 1.7ulp error */
+            x = 0.5f * log1pf(2 * x + 2 * x * x / (1 - x));
+        }
+    } else { /* avoid overflow */
+        x = 0.5f * log1pf(2 * (x / (1 - x)));
+        if (isinf(x)) *_errno() = ERANGE;
+    }
+    return s ? -x : x;
 }
 
 #endif /* _MSVCR_VER>=120 */

dlls/msvcrt/unixlib.c

@@ -56,18 +56,6 @@ static double CDECL unix_atanh(double x)
 }
 
 /*********************************************************************
- *      atanhf
- */
-static float CDECL unix_atanhf(float x)
-{
-#ifdef HAVE_ATANHF
-    return atanhf(x);
-#else
-    return unix_atanh(x);
-#endif
-}
-
-/*********************************************************************
  *      cosh
  */
 static double CDECL unix_cosh( double x )
@@ -394,7 +382,6 @@ static float CDECL unix_tgammaf(float x)
 static const struct unix_funcs funcs =
 {
     unix_atanh,
-    unix_atanhf,
     unix_cosh,
     unix_coshf,
     unix_exp,

dlls/msvcrt/unixlib.h

@@ -24,7 +24,6 @@
 struct unix_funcs
 {
     double          (CDECL *atanh)(double x);
-    float           (CDECL *atanhf)(float x);
     double          (CDECL *cosh)(double x);
     float           (CDECL *coshf)(float x);
     double          (CDECL *exp)(double x);

include/config.h.in

@@ -34,9 +34,6 @@
 /* Define to 1 if you have the `atanh' function. */
 #undef HAVE_ATANH
 
-/* Define to 1 if you have the `atanhf' function. */
-#undef HAVE_ATANHF
-
 /* Define to 1 if you have the <AudioToolbox/AudioConverter.h> header file. */
 #undef HAVE_AUDIOTOOLBOX_AUDIOCONVERTER_H