math: add dummy implementations of 128 bit long double functions

This is in preparation for the aarch64 port only to have the long
double math symbols available on ld128 platforms. The implementations
should be fixed up later once we have proper tests for these functions.

Added bigendian handling for ld128 bit manipulations too.

src/internal/libm.h

@@ -42,6 +42,20 @@ union ldshape {
 		uint64_t hi;
 	} i2;
 };
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384 && __BYTE_ORDER == __BIG_ENDIAN
+union ldshape {
+	long double f;
+	struct {
+		uint16_t se;
+		uint16_t top;
+		uint32_t mid;
+		uint64_t lo;
+	} i;
+	struct {
+		uint64_t hi;
+		uint64_t lo;
+	} i2;
+};
 #else
 #error Unsupported long double representation
 #endif

src/math/acoshl.c

@@ -20,4 +20,10 @@ long double acoshl(long double x)
 		return logl(2*x - 1/(x+sqrtl(x*x-1)));
 	return logl(x) + 0.693147180559945309417232121458176568L;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double acoshl(long double x)
+{
+	return acosh(x);
+}
 #endif

src/math/asinhl.c

@@ -32,4 +32,10 @@ long double asinhl(long double x)
 	}
 	return s ? -x : x;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double asinhl(long double x)
+{
+	return asinh(x);
+}
 #endif

src/math/atanhl.c

@@ -5,7 +5,7 @@ long double atanhl(long double x)
 {
 	return atanh(x);
 }
-#elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
+#elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
 /* atanh(x) = log((1+x)/(1-x))/2 = log1p(2x/(1-x))/2 ~= x + x^3/3 + o(x^5) */
 long double atanhl(long double x)
 {

src/math/coshl.c

@@ -38,4 +38,10 @@ long double coshl(long double x)
 	t = expl(0.5*x);
 	return 0.5*t*t;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double coshl(long double x)
+{
+	return cosh(x);
+}
 #endif

src/math/erfl.c

@@ -340,4 +340,14 @@ long double erfcl(long double x)
 	y = 0x1p-16382L;
 	return sign ? 2 - y : y*y;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double erfl(long double x)
+{
+	return erf(x);
+}
+long double erfcl(long double x)
+{
+	return erfc(x);
+}
 #endif

src/math/expl.c

@@ -119,4 +119,10 @@ long double expl(long double x)
 	x = 1.0 + 2.0 * x;
 	return scalbnl(x, k);
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double expl(long double x)
+{
+	return exp(x);
+}
 #endif

src/math/expm1l.c

@@ -114,4 +114,10 @@ long double expm1l(long double x)
 	x = px * qx + (px - 1.0);
 	return x;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double expm1l(long double x)
+{
+	return expm1(x);
+}
 #endif

src/math/lgammal.c

@@ -340,9 +340,16 @@ long double __lgammal_r(long double x, int *sg) {
 		r = nadj - r;
 	return r;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+double __lgamma_r(double x, int *sg);
+
+long double __lgammal_r(long double x, int *sg)
+{
+	return __lgamma_r(x, sg);
+}
 #endif
 
-#if (LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024) || (LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384)
 extern int __signgam;
 
 long double lgammal(long double x)
@@ -351,4 +358,3 @@ long double lgammal(long double x)
 }
 
 weak_alias(__lgammal_r, lgammal_r);
-#endif

src/math/log10l.c

@@ -182,4 +182,10 @@ done:
 	z += e * (L102A);
 	return z;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double log10l(long double x)
+{
+	return log10(x);
+}
 #endif

src/math/log1pl.c

@@ -168,4 +168,10 @@ long double log1pl(long double xm1)
 	z = z + e * C1;
 	return z;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double log1pl(long double x)
+{
+	return log1p(x);
+}
 #endif

src/math/log2l.c

@@ -173,4 +173,10 @@ done:
 	z += e;
 	return z;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double log2l(long double x)
+{
+	return log2(x);
+}
 #endif

src/math/logl.c

@@ -166,4 +166,10 @@ long double logl(long double x)
 	z = z + e * C1; /* This sum has an error of 1/2 lsb. */
 	return z;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double logl(long double x)
+{
+	return log(x);
+}
 #endif

src/math/powl.c

@@ -513,5 +513,10 @@ static long double powil(long double x, int nn)
 		y = 1.0/y;
 	return y;
 }
-
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double powl(long double x, long double y)
+{
+	return pow(x, y);
+}
 #endif

src/math/sinhl.c

@@ -34,4 +34,10 @@ long double sinhl(long double x)
 	t = expl(0.5*absx);
 	return h*t*t;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double sinhl(long double x)
+{
+	return sinh(x);
+}
 #endif

src/math/tanhl.c

@@ -39,4 +39,10 @@ long double tanhl(long double x)
 	}
 	return sign ? -t : t;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double tanhl(long double x)
+{
+	return tanh(x);
+}
 #endif

src/math/tgammal.c

@@ -272,4 +272,10 @@ small:
 		q = z / (x * __polevll(x, S, 8));
 	return q;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double tgammal(long double x)
+{
+	return tgamma(x);
+}
 #endif