# HG changeset patch # User Bruno Haible # Date 1333472535 -7200 # Node ID f3fe07944aae8758c20775fe496465d3bae3d299 # Parent d48f227b07b4059f5d009838a211ff6ec4607ff5 Tests for module 'ilogb'. * modules/ilogb-tests: New file. * tests/test-ilogb.c: New file. * tests/test-ilogb.h: New file, based on tests/test-logb.h and tests/test-logb-ieee.h. diff --git a/ChangeLog b/ChangeLog --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,11 @@ 2012-04-03 Bruno Haible + Tests for module 'ilogb'. + * modules/ilogb-tests: New file. + * tests/test-ilogb.c: New file. + * tests/test-ilogb.h: New file, based on tests/test-logb.h and + tests/test-logb-ieee.h. + New module 'ilogb'. * lib/math.in.h (ilogb): New declaration. * lib/ilogb.c: New file. diff --git a/modules/ilogb-tests b/modules/ilogb-tests new file mode 100644 --- /dev/null +++ b/modules/ilogb-tests @@ -0,0 +1,19 @@ +Files: +tests/test-ilogb.c +tests/test-ilogb.h +tests/minus-zero.h +tests/infinity.h +tests/nan.h +tests/signature.h +tests/macros.h +tests/randomd.c + +Depends-on: + +configure.ac: + +Makefile.am: +TESTS += test-ilogb +check_PROGRAMS += test-ilogb +test_ilogb_SOURCES = test-ilogb.c randomd.c +test_ilogb_LDADD = $(LDADD) @ILOGB_LIBM@ diff --git a/tests/test-ilogb.c b/tests/test-ilogb.c new file mode 100644 --- /dev/null +++ b/tests/test-ilogb.c @@ -0,0 +1,61 @@ +/* Test of ilogb() function. + Copyright (C) 2012 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 , 2012. */ + +#include + +#include + +#include "signature.h" +SIGNATURE_CHECK (ilogb, int, (double)); + +#include +#include + +#include "minus-zero.h" +#include "infinity.h" +#include "nan.h" +#include "macros.h" + +#undef INFINITY +#undef NAN + +#define DOUBLE double +/* 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. */ +#define VOLATILE volatile +#define INFINITY Infinityd () +#define NAN NaNd () +#define L_(literal) literal +#define MINUS_ZERO minus_zerod +#define MAX_EXP DBL_MAX_EXP +#define MIN_EXP DBL_MIN_EXP +#define MIN_NORMAL_EXP DBL_MIN_EXP +#define ILOGB ilogb +#define RANDOM randomd +#include "test-ilogb.h" + +int +main () +{ + test_function (); + + return 0; +} diff --git a/tests/test-ilogb.h b/tests/test-ilogb.h new file mode 100644 --- /dev/null +++ b/tests/test-ilogb.h @@ -0,0 +1,151 @@ +/* Test of ilogb*() function family. + Copyright (C) 2012 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 . */ + +static DOUBLE +my_ldexp (DOUBLE x, int d) +{ + for (; d > 0; d--) + x *= L_(2.0); + for (; d < 0; d++) + x *= L_(0.5); + return x; +} + +static void +test_function (void) +{ + int i; + VOLATILE DOUBLE x; + int y; + + /* Some particular values. */ + x = L_(0.6); + y = ILOGB (x); + ASSERT (y == -1); + + x = L_(1.2); + y = ILOGB (x); + ASSERT (y == 0); + + x = L_(2.1); + y = ILOGB (x); + ASSERT (y == 1); + + x = L_(3.9); + y = ILOGB (x); + ASSERT (y == 1); + + x = L_(4.0); + y = ILOGB (x); + ASSERT (y == (FLT_RADIX == 2 ? 2 : 1)); + + x = L_(0.25); + y = ILOGB (x); + ASSERT (y == (FLT_RADIX == 2 ? -2 : -1)); + + /* Zero. */ + ASSERT (ILOGB (L_(0.0)) == FP_ILOGB0); + ASSERT (ILOGB (MINUS_ZERO) == FP_ILOGB0); + + /* Infinity. */ + ASSERT (ILOGB (INFINITY) == INT_MAX); + ASSERT (ILOGB (- INFINITY) == INT_MAX); + + /* NaN. */ + ASSERT (ILOGB (NAN) == FP_ILOGBNAN); + + /* From here on, this test assumes FLT_RADIX == 2. */ + + for (i = 1, x = L_(1.0); i <= MAX_EXP; i++, x *= L_(2.0)) + { + y = ILOGB (x); + ASSERT (y == i - 1); + } + for (i = 1, x = L_(1.0); i >= MIN_NORMAL_EXP; i--, x *= L_(0.5)) + { + y = ILOGB (x); + ASSERT (y == i - 1); + } + for (; i >= MIN_EXP - 100 && x > L_(0.0); i--, x *= L_(0.5)) + { + y = ILOGB (x); + ASSERT (y == i - 1); + } + + for (i = 1, x = - L_(1.0); i <= MAX_EXP; i++, x *= L_(2.0)) + { + y = ILOGB (x); + ASSERT (y == i - 1); + } + for (i = 1, x = - L_(1.0); i >= MIN_NORMAL_EXP; i--, x *= L_(0.5)) + { + y = ILOGB (x); + ASSERT (y == i - 1); + } + for (; i >= MIN_EXP - 100 && x < L_(0.0); i--, x *= L_(0.5)) + { + y = ILOGB (x); + ASSERT (y == i - 1); + } + + for (i = 1, x = L_(1.01); i <= MAX_EXP; i++, x *= L_(2.0)) + { + y = ILOGB (x); + ASSERT (y == i - 1); + } + for (i = 1, x = L_(1.01); i >= MIN_NORMAL_EXP; i--, x *= L_(0.5)) + { + y = ILOGB (x); + ASSERT (y == i - 1); + } + for (; i >= MIN_EXP - 100 && x > L_(0.0); i--, x *= L_(0.5)) + { + y = ILOGB (x); + ASSERT (y == i - 1); + } + + for (i = 1, x = L_(1.73205); i <= MAX_EXP; i++, x *= L_(2.0)) + { + y = ILOGB (x); + ASSERT (y == i - 1); + } + for (i = 1, x = L_(1.73205); i >= MIN_NORMAL_EXP; i--, x *= L_(0.5)) + { + y = ILOGB (x); + ASSERT (y == i - 1); + } + for (; i >= MIN_EXP - 100 && x > L_(0.0); i--, x *= L_(0.5)) + { + y = ILOGB (x); + ASSERT (y == i - 1 || y == i); + } + + /* Randomized tests. */ + for (i = 0; i < SIZEOF (RANDOM); i++) + { + x = L_(20.0) * RANDOM[i] - L_(10.0); /* -10.0 <= x <= 10.0 */ + if (x != L_(0.0)) + { + DOUBLE abs_x = (x < L_(0.0) ? - x : x); + y = ILOGB (x); + ASSERT (abs_x >= my_ldexp (L_(1.0), y)); + ASSERT (abs_x < my_ldexp (L_(1.0), y + 1)); + } + } +} + +volatile DOUBLE x; +DOUBLE y;