msun: ctanh/ctanhf: Import fix from musl libc

This applies musl commit b02eed9c4841913d690a2d0029737d72615384fe by
Szabolcs Nagy and updates the tests accordingly. This also allows
removing an XFAIL from the test.

musl commit message:

complex: fix ctanh(+-0+i*nan) and ctanh(+-0+-i*inf)

These cases were incorrect in C11 as described by
http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1886.htm

PR: 217528

Reviewed By:	dim
MFC after:	1 week
Differential Revision: https://reviews.freebsd.org/D28578

(cherry picked from commit a7b42c4b7f7ad7bd1b22ab57ed9185bdcea6f0a2)

3 files changed, 14 insertions, 19 deletions

diff --git a/lib/msun/src/s_ctanh.c b/lib/msun/src/s_ctanh.c
index 13eb9d40b678..93e5ad444501 100644
--- a/lib/msun/src/s_ctanh.c
+++ b/lib/msun/src/s_ctanh.c
@@ -111,11 +111,13 @@ ctanh(double complex z)
 	}
 
 	/*
-	 * ctanh(x + I NaN) = d(NaN) + I d(NaN)
-	 * ctanh(x +- I Inf) = dNaN + I dNaN
+	 * ctanh(+-0 + i NAN) = +-0 + i NaN
+	 * ctanh(+-0 +- i Inf) = +-0 + i NaN
+	 * ctanh(x + i NAN) = NaN + i NaN
+	 * ctanh(x +- i Inf) = NaN + i NaN
 	 */
 	if (!isfinite(y))
-		return (CMPLX(y - y, y - y));
+		return (CMPLX(x ? y - y : x, y - y));
 
 	/*
 	 * ctanh(+-huge +- I y) ~= +-1 +- I 2sin(2y)/exp(2x), using the
diff --git a/lib/msun/src/s_ctanhf.c b/lib/msun/src/s_ctanhf.c
index 7d375eafd2ae..164a2c23df9e 100644
--- a/lib/msun/src/s_ctanhf.c
+++ b/lib/msun/src/s_ctanhf.c
@@ -61,7 +61,7 @@ ctanhf(float complex z)
 	}
 
 	if (!isfinite(y))
-		return (CMPLXF(y - y, y - y));
+		return (CMPLXF(ix ? y - y : x, y - y));
 
 	if (ix >= 0x41300000) {	/* |x| >= 11 */
 		float exp_mx = expf(-fabsf(x));
diff --git a/lib/msun/tests/ctrig_test.c b/lib/msun/tests/ctrig_test.c
index 45b2b78b0416..b40373fed29b 100644
--- a/lib/msun/tests/ctrig_test.c
+++ b/lib/msun/tests/ctrig_test.c
@@ -138,13 +138,6 @@ ATF_TC_BODY(test_zero_input, tc)
 {
 	long double complex zero = CMPLXL(0.0, 0.0);
 
-#if defined(__amd64__)
-#if defined(__clang__) && \
-	((__clang_major__ >= 4))
-	atf_tc_expect_fail("test fails with clang 4.x+ - bug 217528");
-#endif
-#endif
-
 	/* csinh(0) = ctanh(0) = 0; ccosh(0) = 1 (no exceptions raised) */
 	testall_odd(csinh, zero, zero, ALL_STD_EXCEPT, 0, CS_BOTH);
 	testall_odd(csin, zero, zero, ALL_STD_EXCEPT, 0, CS_BOTH);
@@ -171,8 +164,8 @@ ATF_TC_BODY(test_nan_inputs, tc)
 	 * NaN,finite	NaN,NaN [inval]	NaN,NaN [inval]	NaN,NaN [inval]
 	 * NaN,Inf	NaN,NaN [inval]	NaN,NaN	[inval]	NaN,NaN [inval]
 	 * Inf,NaN	+-Inf,NaN	Inf,NaN		1,+-0
-	 * 0,NaN	+-0,NaN		NaN,+-0		NaN,NaN	[inval]
-	 * NaN,0	NaN,0		NaN,+-0		NaN,0
+	 * 0,NaN	+-0,NaN		NaN,+-0		+-0,NaN
+	 * NaN,0	NaN,0		NaN,+-0		NaN,+-0
 	 */
 	z = nan_nan;
 	testall_odd(csinh, z, nan_nan, ALL_STD_EXCEPT, 0, 0);
@@ -219,9 +212,9 @@ ATF_TC_BODY(test_nan_inputs, tc)
 	testall_odd(ctan, z, nan_nan, OPT_INVALID, 0, 0);
 
 	z = CMPLXL(0, NAN);
-	testall_odd(csinh, z, CMPLXL(0, NAN), ALL_STD_EXCEPT, 0, 0);
+	testall_odd(csinh, z, CMPLXL(0, NAN), ALL_STD_EXCEPT, 0, CS_REAL);
 	testall_even(ccosh, z, CMPLXL(NAN, 0), ALL_STD_EXCEPT, 0, 0);
-	testall_odd(ctanh, z, nan_nan, OPT_INVALID, 0, 0);
+	testall_odd(ctanh, z, CMPLXL(0, NAN), OPT_INVALID, 0, CS_REAL);
 	testall_odd(csin, z, CMPLXL(0, NAN), ALL_STD_EXCEPT, 0, CS_REAL);
 	testall_even(ccos, z, CMPLXL(NAN, 0), ALL_STD_EXCEPT, 0, 0);
 	testall_odd(ctan, z, CMPLXL(0, NAN), ALL_STD_EXCEPT, 0, CS_REAL);
@@ -232,7 +225,7 @@ ATF_TC_BODY(test_nan_inputs, tc)
 	testall_odd(ctanh, z, CMPLXL(NAN, 0), ALL_STD_EXCEPT, 0, CS_IMAG);
 	testall_odd(csin, z, CMPLXL(NAN, 0), ALL_STD_EXCEPT, 0, 0);
 	testall_even(ccos, z, CMPLXL(NAN, 0), ALL_STD_EXCEPT, 0, 0);
-	testall_odd(ctan, z, nan_nan, OPT_INVALID, 0, 0);
+	testall_odd(ctan, z, CMPLXL(NAN, 0), ALL_STD_EXCEPT, 0, CS_IMAG);
 }
 
 ATF_TC(test_inf_inputs);
@@ -252,7 +245,7 @@ ATF_TC_BODY(test_inf_inputs, tc)
 	 * IN		CSINH		CCOSH		CTANH
 	 * Inf,Inf	+-Inf,NaN inval	+-Inf,NaN inval	1,+-0
 	 * Inf,finite	Inf cis(finite)	Inf cis(finite)	1,0 sin(2 finite)
-	 * 0,Inf	+-0,NaN	inval	NaN,+-0 inval	NaN,NaN	inval
+	 * 0,Inf	+-0,NaN	inval	NaN,+-0 inval	+-0,NaN
 	 * finite,Inf	NaN,NaN inval	NaN,NaN inval	NaN,NaN inval
 	 */
 	z = CMPLXL(INFINITY, INFINITY);
@@ -286,11 +279,11 @@ ATF_TC_BODY(test_inf_inputs, tc)
 	z = CMPLXL(0, INFINITY);
 	testall_odd(csinh, z, CMPLXL(0, NAN), ALL_STD_EXCEPT, FE_INVALID, 0);
 	testall_even(ccosh, z, CMPLXL(NAN, 0), ALL_STD_EXCEPT, FE_INVALID, 0);
-	testall_odd(ctanh, z, CMPLXL(NAN, NAN), ALL_STD_EXCEPT, FE_INVALID, 0);
+	testall_odd(ctanh, z, CMPLXL(0, NAN), ALL_STD_EXCEPT, FE_INVALID, CS_REAL);
 	z = CMPLXL(INFINITY, 0);
 	testall_odd(csin, z, CMPLXL(NAN, 0), ALL_STD_EXCEPT, FE_INVALID, 0);
 	testall_even(ccos, z, CMPLXL(NAN, 0), ALL_STD_EXCEPT, FE_INVALID, 0);
-	testall_odd(ctan, z, CMPLXL(NAN, NAN), ALL_STD_EXCEPT, FE_INVALID, 0);
+	testall_odd(ctan, z, CMPLXL(NAN, 0), ALL_STD_EXCEPT, FE_INVALID, CS_IMAG);
 
 	z = CMPLXL(42, INFINITY);
 	testall_odd(csinh, z, CMPLXL(NAN, NAN), ALL_STD_EXCEPT, FE_INVALID, 0);