From fa095a4504cbe668e4244547e2c141597bea4ecf Mon Sep 17 00:00:00 2001 From: Andreas Rottmann Date: Mon, 14 Sep 2009 12:32:44 +0200 Subject: Imported Upstream version 0.9.1 --- tests/test-printf-frexp.c | 131 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 131 insertions(+) create mode 100644 tests/test-printf-frexp.c (limited to 'tests/test-printf-frexp.c') diff --git a/tests/test-printf-frexp.c b/tests/test-printf-frexp.c new file mode 100644 index 0000000..8ba9348 --- /dev/null +++ b/tests/test-printf-frexp.c @@ -0,0 +1,131 @@ +/* Test of splitting a double into fraction and mantissa. + Copyright (C) 2007-2008 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . */ + +/* Written by Bruno Haible , 2007. */ + +#include + +#include "printf-frexp.h" + +#include +#include +#include + +#define ASSERT(expr) \ + do \ + { \ + if (!(expr)) \ + { \ + fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \ + fflush (stderr); \ + abort (); \ + } \ + } \ + while (0) + +static double +my_ldexp (double x, int d) +{ + for (; d > 0; d--) + x *= 2.0; + for (; d < 0; d++) + x *= 0.5; + return x; +} + +int +main () +{ + int i; + /* The use of 'volatile' guarantees that excess precision bits are dropped + when dealing with denormalized numbers. It is necessary on x86 systems + where double-floats are not IEEE compliant by default, to avoid that the + results become platform and compiler option dependent. 'volatile' is a + portable alternative to gcc's -ffloat-store option. */ + volatile double x; + + for (i = 1, x = 1.0; i <= DBL_MAX_EXP; i++, x *= 2.0) + { + int exp = -9999; + double mantissa = printf_frexp (x, &exp); + ASSERT (exp == i - 1); + ASSERT (mantissa == 1.0); + } + for (i = 1, x = 1.0; i >= DBL_MIN_EXP; i--, x *= 0.5) + { + int exp = -9999; + double mantissa = printf_frexp (x, &exp); + ASSERT (exp == i - 1); + ASSERT (mantissa == 1.0); + } + for (; i >= DBL_MIN_EXP - 100 && x > 0.0; i--, x *= 0.5) + { + int exp = -9999; + double mantissa = printf_frexp (x, &exp); + ASSERT (exp == DBL_MIN_EXP - 1); + ASSERT (mantissa == my_ldexp (1.0, i - DBL_MIN_EXP)); + } + + for (i = 1, x = 1.01; i <= DBL_MAX_EXP; i++, x *= 2.0) + { + int exp = -9999; + double mantissa = printf_frexp (x, &exp); + ASSERT (exp == i - 1); + ASSERT (mantissa == 1.01); + } + for (i = 1, x = 1.01; i >= DBL_MIN_EXP; i--, x *= 0.5) + { + int exp = -9999; + double mantissa = printf_frexp (x, &exp); + ASSERT (exp == i - 1); + ASSERT (mantissa == 1.01); + } + for (; i >= DBL_MIN_EXP - 100 && x > 0.0; i--, x *= 0.5) + { + int exp = -9999; + double mantissa = printf_frexp (x, &exp); + ASSERT (exp == DBL_MIN_EXP - 1); + ASSERT (mantissa >= my_ldexp (1.0, i - DBL_MIN_EXP)); + ASSERT (mantissa <= my_ldexp (2.0, i - DBL_MIN_EXP)); + ASSERT (mantissa == my_ldexp (x, - exp)); + } + + for (i = 1, x = 1.73205; i <= DBL_MAX_EXP; i++, x *= 2.0) + { + int exp = -9999; + double mantissa = printf_frexp (x, &exp); + ASSERT (exp == i - 1); + ASSERT (mantissa == 1.73205); + } + for (i = 1, x = 1.73205; i >= DBL_MIN_EXP; i--, x *= 0.5) + { + int exp = -9999; + double mantissa = printf_frexp (x, &exp); + ASSERT (exp == i - 1); + ASSERT (mantissa == 1.73205); + } + for (; i >= DBL_MIN_EXP - 100 && x > 0.0; i--, x *= 0.5) + { + int exp = -9999; + double mantissa = printf_frexp (x, &exp); + ASSERT (exp == DBL_MIN_EXP - 1); + ASSERT (mantissa >= my_ldexp (1.0, i - DBL_MIN_EXP)); + ASSERT (mantissa <= my_ldexp (2.0, i - DBL_MIN_EXP)); + ASSERT (mantissa == my_ldexp (x, - exp)); + } + + return 0; +} -- cgit v1.2.3