From c85e54ac6cef0faed7b7ffc722f52523dec59bf5 Mon Sep 17 00:00:00 2001 From: "Gabriel F. T. Gomes" Date: Fri, 3 Nov 2017 10:44:36 -0200 Subject: Provide a C++ version of iseqsig (bug 22377) In C++ mode, __MATH_TG cannot be used for defining iseqsig, because __MATH_TG relies on __builtin_types_compatible_p, which is a C-only builtin. This is true when float128 is provided as an ABI-distinct type from long double. Moreover, the comparison macros from ISO C take two floating-point arguments, which need not have the same type. Choosing what underlying function to call requires evaluating the formats of the arguments, then selecting which is wider. The macro __MATH_EVAL_FMT2 provides this information, however, only the type of the macro expansion is relevant (actually evaluating the expression would be incorrect). This patch provides a C++ version of iseqsig, in which only the type of __MATH_EVAL_FMT2 (__typeof or decltype) is used as a template parameter for __iseqsig_type. This function calls the appropriate underlying function. Tested for powerpc64le and x86_64. [BZ #22377] * math/Makefile [C++] (tests): Add test for iseqsig. * math/math.h [C++] (iseqsig): New implementation, which does not rely on __MATH_TG/__builtin_types_compatible_p. * math/test-math-iseqsig.cc: New file. * sysdeps/powerpc/powerpc64le/Makefile (CFLAGS-test-math-iseqsig.cc): New variable. --- math/Makefile | 2 +- math/math.h | 72 +++++++++++++++++++++++++++++- math/test-math-iseqsig.cc | 111 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 182 insertions(+), 3 deletions(-) create mode 100644 math/test-math-iseqsig.cc (limited to 'math') diff --git a/math/Makefile b/math/Makefile index cba9ce9405..8978f2ef96 100644 --- a/math/Makefile +++ b/math/Makefile @@ -220,7 +220,7 @@ tests-static += atest-exp atest-sincos atest-exp2 ifneq (,$(CXX)) tests += test-math-isinff test-math-iszero test-math-issignaling \ - test-math-iscanonical test-math-cxx11 + test-math-iscanonical test-math-cxx11 test-math-iseqsig endif ifneq (no,$(PERL)) diff --git a/math/math.h b/math/math.h index f6d1feed78..72d7dc5939 100644 --- a/math/math.h +++ b/math/math.h @@ -1182,8 +1182,76 @@ iszero (__T __val) /* Return X == Y but raising "invalid" and setting errno if X or Y is a NaN. */ -# define iseqsig(x, y) \ - __MATH_TG (__MATH_EVAL_FMT2 (x, y), __iseqsig, ((x), (y))) +# if !defined __cplusplus || (__cplusplus < 201103L && !defined __GNUC__) +# define iseqsig(x, y) \ + __MATH_TG (__MATH_EVAL_FMT2 (x, y), __iseqsig, ((x), (y))) +# else +/* In C++ mode, __MATH_TG cannot be used, because it relies on + __builtin_types_compatible_p, which is a C-only builtin. Moreover, + the comparison macros from ISO C take two floating-point arguments, + which need not have the same type. Choosing what underlying function + to call requires evaluating the formats of the arguments, then + selecting which is wider. The macro __MATH_EVAL_FMT2 provides this + information, however, only the type of the macro expansion is + relevant (actually evaluating the expression would be incorrect). + Thus, the type is used as a template parameter for __iseqsig_type, + which calls the appropriate underlying function. */ +extern "C++" { +template struct __iseqsig_type; + +template<> struct __iseqsig_type +{ + static int __call (float __x, float __y) throw () + { + return __iseqsigf (__x, __y); + } +}; + +template<> struct __iseqsig_type +{ + static int __call (double __x, double __y) throw () + { + return __iseqsig (__x, __y); + } +}; + +template<> struct __iseqsig_type +{ + static int __call (double __x, double __y) throw () + { +# ifndef __NO_LONG_DOUBLE_MATH + return __iseqsigl (__x, __y); +# else + return __iseqsig (__x, __y); +# endif + } +}; + +# if __HAVE_DISTINCT_FLOAT128 +template<> struct __iseqsig_type<_Float128> +{ + static int __call (_Float128 __x, _Float128 __y) throw () + { + return __iseqsigf128 (__x, __y); + } +}; +# endif + +template +inline int +iseqsig (_T1 __x, _T2 __y) throw () +{ +# if __cplusplus >= 201103L + typedef decltype (__MATH_EVAL_FMT2 (__x, __y)) _T3; +# else + typedef __typeof (__MATH_EVAL_FMT2 (__x, __y)) _T3; +# endif + return __iseqsig_type<_T3>::__call (__x, __y); +} + +} /* extern "C++" */ +# endif /* __cplusplus */ + #endif __END_DECLS diff --git a/math/test-math-iseqsig.cc b/math/test-math-iseqsig.cc new file mode 100644 index 0000000000..48e8f1e799 --- /dev/null +++ b/math/test-math-iseqsig.cc @@ -0,0 +1,111 @@ +/* Test for the C++ implementation of iseqsig. + Copyright (C) 2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#define _GNU_SOURCE 1 +#include +#include + +#include + +/* There is no NaN for _Float128 in std::numeric_limits. + Include ieee754_float128.h and use the bitfields in the union + ieee854_float128.ieee_nan to build a NaN. */ +#if __HAVE_DISTINCT_FLOAT128 +# include +#endif + +#include + +static void +check (int actual, int expected, const char *actual_expr, int line) +{ + if (actual != expected) + { + support_record_failure (); + printf ("%s:%d: error: %s\n", __FILE__, line, actual_expr); + printf ("%s:%d: expected: %d\n", __FILE__, line, expected); + printf ("%s:%d: actual: %d\n", __FILE__, line, actual); + } +} + +#define CHECK(actual, expected) \ + check ((actual), (expected), #actual, __LINE__) + +template +static void +check_type () +{ + T1 t1 = 0; + T2 t2 = 0; + CHECK (iseqsig (t1, t2), 1); + + t2 = 1; + CHECK (iseqsig (t1, t2), 0); + + if (std::numeric_limits::has_quiet_NaN + && std::numeric_limits::has_quiet_NaN) + { + CHECK (iseqsig (std::numeric_limits::quiet_NaN (), t2), 0); + CHECK (iseqsig (t1, std::numeric_limits::quiet_NaN ()), 0); + CHECK (iseqsig (std::numeric_limits::quiet_NaN (), + std::numeric_limits::quiet_NaN ()), 0); + } +} + +#if __HAVE_DISTINCT_FLOAT128 +static void +check_float128 () +{ + ieee854_float128 q1, q2, q3_nan; + + q1.d = 0; + q2.d = 1; + q3_nan.ieee_nan.negative = 0; + q3_nan.ieee_nan.exponent = 0x7FFF; + q3_nan.ieee_nan.quiet_nan = 1; + q3_nan.ieee_nan.mantissa0 = 0x0000; + q3_nan.ieee_nan.mantissa1 = 0x00000000; + q3_nan.ieee_nan.mantissa2 = 0x00000000; + q3_nan.ieee_nan.mantissa3 = 0x00000000; + + CHECK (iseqsig (q1.d, q1.d), 1); + CHECK (iseqsig (q1.d, q2.d), 0); + CHECK (iseqsig (q1.d, q3_nan.d), 0); + CHECK (iseqsig (q3_nan.d, q3_nan.d), 0); +} +#endif + +static int +do_test (void) +{ + check_type (); + check_type (); + check_type (); + check_type (); + check_type (); + check_type (); + check_type (); + check_type (); + check_type (); +#if __HAVE_DISTINCT_FLOAT128 + check_float128 (); +#endif + return 0; +} + +#include -- cgit v1.2.3