msvcrt: Use the log1p()/log1pf() implementation from the bundled musl library.

dlls/msvcrt/math.c

@@ -5497,150 +5497,6 @@ void __cdecl __libm_sse2_sqrt_precise(void)
 #if _MSVCR_VER>=120
 
 /*********************************************************************
- *      log1p (MSVCR120.@)
- *
- * Copied from musl: src/math/log1p.c
- */
-double CDECL log1p(double x)
-{
-    static const double ln2_hi = 6.93147180369123816490e-01,
-        ln2_lo = 1.90821492927058770002e-10,
-        Lg1 = 6.666666666666735130e-01,
-        Lg2 = 3.999999999940941908e-01,
-        Lg3 = 2.857142874366239149e-01,
-        Lg4 = 2.222219843214978396e-01,
-        Lg5 = 1.818357216161805012e-01,
-        Lg6 = 1.531383769920937332e-01,
-        Lg7 = 1.479819860511658591e-01;
-
-    union {double f; UINT64 i;} u = {x};
-    double hfsq, f, c, s, z, R, w, t1, t2, dk;
-    UINT32 hx, hu;
-    int k;
-
-    hx = u.i >> 32;
-    k = 1;
-    if (hx < 0x3fda827a || hx >> 31) { /* 1+x < sqrt(2)+ */
-        if (hx >= 0xbff00000) { /* x <= -1.0 */
-            if (x == -1) {
-                *_errno() = ERANGE;
-                return x / 0.0; /* og1p(-1) = -inf */
-            }
-            *_errno() = EDOM;
-            return (x-x) / 0.0; /* log1p(x<-1) = NaN */
-        }
-        if (hx << 1 < 0x3ca00000 << 1) { /* |x| < 2**-53 */
-            fp_barrier(x + 0x1p120f);
-            /* underflow if subnormal */
-            if ((hx & 0x7ff00000) == 0)
-                fp_barrierf(x);
-            return x;
-        }
-        if (hx <= 0xbfd2bec4) { /* sqrt(2)/2- <= 1+x < sqrt(2)+ */
-            k = 0;
-            c = 0;
-            f = x;
-        }
-    } else if (hx >= 0x7ff00000)
-        return x;
-    if (k) {
-        u.f = 1 + x;
-        hu = u.i >> 32;
-        hu += 0x3ff00000 - 0x3fe6a09e;
-        k = (int)(hu >> 20) - 0x3ff;
-        /* correction term ~ log(1+x)-log(u), avoid underflow in c/u */
-        if (k < 54) {
-            c = k >= 2 ? 1 - (u.f - x) : x - (u.f - 1);
-            c /= u.f;
-        } else
-            c = 0;
-        /* reduce u into [sqrt(2)/2, sqrt(2)] */
-        hu = (hu & 0x000fffff) + 0x3fe6a09e;
-        u.i = (UINT64)hu << 32 | (u.i & 0xffffffff);
-        f = u.f - 1;
-    }
-    hfsq = 0.5 * f * f;
-    s = f / (2.0 + f);
-    z = s * s;
-    w = z * z;
-    t1 = w * (Lg2 + w * (Lg4 + w * Lg6));
-    t2 = z * (Lg1 + w * (Lg3 + w * (Lg5 + w * Lg7)));
-    R = t2 + t1;
-    dk = k;
-    return s * (hfsq + R) + (dk * ln2_lo + c) - hfsq + f + dk * ln2_hi;
-}
-
-/*********************************************************************
- *      log1pf (MSVCR120.@)
- *
- * Copied from musl: src/math/log1pf.c
- */
-float CDECL log1pf(float x)
-{
-    static const float ln2_hi = 6.9313812256e-01,
-        ln2_lo = 9.0580006145e-06,
-        Lg1 = 0xaaaaaa.0p-24,
-        Lg2 = 0xccce13.0p-25,
-        Lg3 = 0x91e9ee.0p-25,
-        Lg4 = 0xf89e26.0p-26;
-
-    union {float f; UINT32 i;} u = {x};
-    float hfsq, f, c, s, z, R, w, t1, t2, dk;
-    UINT32 ix, iu;
-    int k;
-
-    ix = u.i;
-    k = 1;
-    if (ix < 0x3ed413d0 || ix >> 31) { /* 1+x < sqrt(2)+ */
-        if (ix >= 0xbf800000) { /* x <= -1.0 */
-            if (x == -1) {
-                *_errno() = ERANGE;
-                return x / 0.0f; /* log1p(-1)=+inf */
-            }
-            *_errno() = EDOM;
-            return (x - x) / 0.0f; /* log1p(x<-1)=NaN */
-        }
-        if (ix<<1 < 0x33800000<<1) { /* |x| < 2**-24 */
-            /* underflow if subnormal */
-            if ((ix & 0x7f800000) == 0)
-                fp_barrierf(x * x);
-            return x;
-        }
-        if (ix <= 0xbe95f619) { /* sqrt(2)/2- <= 1+x < sqrt(2)+ */
-            k = 0;
-            c = 0;
-            f = x;
-        }
-    } else if (ix >= 0x7f800000)
-        return x;
-    if (k) {
-        u.f = 1 + x;
-        iu = u.i;
-        iu += 0x3f800000 - 0x3f3504f3;
-        k = (int)(iu >> 23) - 0x7f;
-        /* correction term ~ log(1+x)-log(u), avoid underflow in c/u */
-        if (k < 25) {
-            c = k >= 2 ? 1 - (u.f - x) : x - (u.f - 1);
-            c /= u.f;
-        } else
-            c = 0;
-        /* reduce u into [sqrt(2)/2, sqrt(2)] */
-        iu = (iu & 0x007fffff) + 0x3f3504f3;
-        u.i = iu;
-        f = u.f - 1;
-    }
-    s = f / (2.0f + f);
-    z = s * s;
-    w = z * z;
-    t1= w * (Lg2 + w * Lg4);
-    t2= z * (Lg1 + w * Lg3);
-    R = t2 + t1;
-    hfsq = 0.5f * f * f;
-    dk = k;
-    return s * (hfsq + R) + (dk * ln2_lo + c) - hfsq + f + dk * ln2_hi;
-}
-
-/*********************************************************************
  *      log2 (MSVCR120.@)
  *
  * Copied from musl: src/math/log2.c

libs/musl/src/math/log1p.c

@@ -77,11 +77,15 @@ double __cdecl log1p(double x)
 	k = 1;
 	if (hx < 0x3fda827a || hx>>31) {  /* 1+x < sqrt(2)+ */
 		if (hx >= 0xbff00000) {  /* x <= -1.0 */
-			if (x == -1)
+			if (x == -1) {
+				errno = ERANGE;
 				return x/0.0; /* log1p(-1) = -inf */
+			}
+			errno = EDOM;
 			return (x-x)/0.0;     /* log1p(x<-1) = NaN */
 		}
 		if (hx<<1 < 0x3ca00000<<1) {  /* |x| < 2**-53 */
+			fp_barrier(x + 0x1p120f);
 			/* underflow if subnormal */
 			if ((hx&0x7ff00000) == 0)
 				FORCE_EVAL((float)x);

libs/musl/src/math/log1pf.c

@@ -32,8 +32,11 @@ float __cdecl log1pf(float x)
 	k = 1;
 	if (ix < 0x3ed413d0 || ix>>31) {  /* 1+x < sqrt(2)+  */
 		if (ix >= 0xbf800000) {  /* x <= -1.0 */
-			if (x == -1)
+			if (x == -1) {
+				errno = ERANGE;
 				return x/0.0f; /* log1p(-1)=+inf */
+			}
+			errno = EDOM;
 			return (x-x)/0.0f;     /* log1p(x<-1)=NaN */
 		}
 		if (ix<<1 < 0x33800000<<1) {   /* |x| < 2**-24 */