Support sNaN testing in libm-test.inc.

This patch adds support in libm-test.inc for tests with signaling NaN
arguments.  gen-libm-test.pl is made to set a flag TEST_SNAN for such
tests, so that they can be disabled automatically when sNaN testing
isn't supported for a given type (at present, for float and double on
32-bit x86 because it's unpredictable when a value might be loaded
into a floating-point register and so automatically converted to long
double with sNaNs converted to quiet NaNs).  -fsignaling-nans is used
where needed.

Tests are added for classification macros, as a starting point; this
is deliberately more conservative than Thomas's patch
<https://sourceware.org/ml/libc-ports/2013-04/msg00008.html>, to allow
more tests to be added, and issues exposed fixed, bit by bit.

Tested for x86_64 and x86.

	* math/libm-test.inc: Update comment about NaN testing.
	(TEST_SNAN): New macro.
	(snan_value): Likewise.
	(enable_test): Disable tests of sNaNs when SNAN_TESTS fails.
	(fpclassify_test_data): Add sNaN tests.
	(isfinite_test_data): Likewise.
	(isinf_test_data): Likewise.
	(isnan_test_data): Likewise.
	(isnormal_test_data): Likewise.
	(issignaling_test_data): Likewise.
	(signbit_test_data): Likewise.
	* math/gen-libm-test.pl (%beautify): Add snan_value.
	(show_exceptions): Add argument $test_snan.
	(parse_args): Handle snan_value as non-finite.  Update call to
	show_exceptions.
	* math/Makefile (libm-test-no-inline-cflags): Add
	-fsignaling-nans.

1 files changed, 19 insertions, 2 deletions

diff --git a/math/libm-test.inc b/math/libm-test.inc
index 169be7e85f..7d29700775 100644
--- a/math/libm-test.inc
+++ b/math/libm-test.inc
@@ -79,8 +79,7 @@
    against.  These implemented tests should check all cases that are
    specified in ISO C99.
 
-   NaN values: There exist signalling and quiet NaNs.  This implementation
-   only uses quiet NaN as parameter.  The payload of NaNs is not examined.
+   NaN values: The payload of NaNs is not examined.
 
    Inline functions: Inlining functions should give an improvement in
    speed - but not in precission.  The inlined functions return
@@ -182,6 +181,7 @@ struct ulp_data
 /* Flags generated by gen-libm-test.pl, not entered here manually.  */
 #define IGNORE_RESULT			0x20000
 #define NON_FINITE			0x40000
+#define TEST_SNAN			0x80000
 
 /* Values underflowing only for float.  */
 #ifdef TEST_FLOAT
@@ -311,6 +311,7 @@ static int ignore_max_ulp;	/* Should we ignore max_ulp?  */
 #define minus_infty	CHOOSE (-HUGE_VALL, -HUGE_VAL, -HUGE_VALF,	\
 				-HUGE_VALL, -HUGE_VAL, -HUGE_VALF)
 #define qnan_value	FUNC (__builtin_nan) ("")
+#define snan_value	FUNC (__builtin_nans) ("")
 #define max_value	CHOOSE (LDBL_MAX, DBL_MAX, FLT_MAX,	\
 				LDBL_MAX, DBL_MAX, FLT_MAX)
 #define min_value	CHOOSE (LDBL_MIN, DBL_MIN, FLT_MIN,	\
@@ -1050,6 +1051,8 @@ enable_test (int exceptions)
     return 0;
   if (TEST_FINITE && (exceptions & NON_FINITE) != 0)
     return 0;
+  if (!SNAN_TESTS (FLOAT) && (exceptions & TEST_SNAN) != 0)
+    return 0;
   return 1;
 }
 
@@ -7691,6 +7694,8 @@ static const struct test_f_i_data fpclassify_test_data[] =
   {
     TEST_f_i (fpclassify, qnan_value, FP_NAN, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_i (fpclassify, -qnan_value, FP_NAN, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_i (fpclassify, snan_value, FP_NAN, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_i (fpclassify, -snan_value, FP_NAN, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_i (fpclassify, plus_infty, FP_INFINITE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_i (fpclassify, minus_infty, FP_INFINITE, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_i (fpclassify, plus_zero, FP_ZERO, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
@@ -7932,6 +7937,8 @@ static const struct test_f_i_data isfinite_test_data[] =
     TEST_f_b (isfinite, minus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isfinite, qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isfinite, -qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_b (isfinite, snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_b (isfinite, -snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
   };
 
 static void
@@ -8032,6 +8039,8 @@ static const struct test_f_i_data isinf_test_data[] =
     TEST_f_b (isinf, minus_infty, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isinf, qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isinf, -qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_b (isinf, snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_b (isinf, -snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
   };
 
 static void
@@ -8160,6 +8169,8 @@ static const struct test_f_i_data isnan_test_data[] =
     TEST_f_b (isnan, minus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isnan, qnan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isnan, -qnan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_b (isnan, snan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_b (isnan, -snan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
   };
 
 static void
@@ -8183,6 +8194,8 @@ static const struct test_f_i_data isnormal_test_data[] =
     TEST_f_b (isnormal, minus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isnormal, qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (isnormal, -qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_b (isnormal, snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_b (isnormal, -snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
   };
 
 static void
@@ -8206,6 +8219,8 @@ static const struct test_f_i_data issignaling_test_data[] =
     TEST_f_b (issignaling, minus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (issignaling, qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (issignaling, -qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_b (issignaling, snan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_b (issignaling, -snan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
   };
 
 static void
@@ -11245,6 +11260,8 @@ static const struct test_f_i_data signbit_test_data[] =
     TEST_f_b (signbit, minus_infty, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (signbit, qnan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
     TEST_f_b (signbit, -qnan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_b (signbit, snan_value, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_b (signbit, -snan_value, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
 
     /* signbit (x) != 0 for x < 0.  */
     TEST_f_b (signbit, -1, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),