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#include <assert.h>
#include <fenv.h>
#include <math.h>
#include <signal.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <machine/frame.h>
int max_error = 4;
#include "common.h"
/* maximum allowed FP difference for our tests */
#define EPSILON 0.00000000023283064365386962890625 /* 2^(-32) */
#define ERR(x, y) e(__LINE__, (x), (y))
static void signal_handler(int signum)
{
struct sigframe_sigcontext *sigframe;
/* report signal */
sigframe = (struct sigframe_sigcontext *) ((char *) &signum -
(char *) &((struct sigframe_sigcontext *) NULL)->sf_signum);
printf("Signal %d at 0x%x\n", signum, sigframe->sf_scp->sc_eip);
/* count as error */
e(0);
fflush(stdout);
/* handle signa again next time */
signal(signum, signal_handler);
}
static void test_fpclassify(double value, int class, int test_sign)
{
/* test fpclassify */
if (fpclassify(value) != class) e(101);
if (test_sign)
{
if (fpclassify(-value) != class) e(102);
/* test signbit */
if (signbit(value)) e(103);
if (!signbit(-value)) e(104);
}
}
/* Maximum normal double: (2 - 2^(-53)) * 2^1023 */
#define NORMAL_DOUBLE_MAX 1.797693134862315708145274237317e+308
/* Minimum normal double: 2^(-1022) */
#define NORMAL_DOUBLE_MIN 2.2250738585072013830902327173324e-308
/* Maximum subnormal double: (1 - 2^(-53)) * 2^(-1022) */
#define SUBNORMAL_DOUBLE_MAX 2.2250738585072008890245868760859e-308
/* Minimum subnormal double: 2^(-52) * 2^(-1023) */
#define SUBNORMAL_DOUBLE_MIN 4.9406564584124654417656879286822e-324
static void test_fpclassify_values(void)
{
double d;
char negzero[] = { 0, 0, 0, 0, 0, 0, 0, 0x80 };
/* test some corner cases for fpclassify and signbit */
test_fpclassify(INFINITY, FP_INFINITE, 1);
test_fpclassify(NAN, FP_NAN, 0);
test_fpclassify(0, FP_ZERO, 0);
test_fpclassify(1, FP_NORMAL, 1);
test_fpclassify(NORMAL_DOUBLE_MAX, FP_NORMAL, 1);
test_fpclassify(NORMAL_DOUBLE_MIN, FP_NORMAL, 1);
test_fpclassify(SUBNORMAL_DOUBLE_MAX, FP_SUBNORMAL, 1);
test_fpclassify(SUBNORMAL_DOUBLE_MIN, FP_SUBNORMAL, 1);
/*
* unfortunately the minus operator does not change the sign of zero,
* so a special case is needed to test it
*/
assert(sizeof(negzero) == sizeof(double));
test_fpclassify(*(double *) negzero, FP_ZERO, 0);
if (!signbit(*(double *) negzero)) e(4);
/* test other small numbers for fpclassify and signbit */
d = 1;
while (d >= NORMAL_DOUBLE_MIN)
{
test_fpclassify(d, FP_NORMAL, 1);
d /= 10;
}
while (d >= SUBNORMAL_DOUBLE_MIN)
{
test_fpclassify(d, FP_SUBNORMAL, 1);
d /= 10;
}
test_fpclassify(d, FP_ZERO, 0);
/* test other large numbers for fpclassify and signbit */
d = 1;
while (d <= NORMAL_DOUBLE_MAX / 10)
{
test_fpclassify(d, FP_NORMAL, 1);
d *= 10;
}
}
/* expected rounding: up, down or identical */
#define ROUND_EQ 1
#define ROUND_DN 2
#define ROUND_UP 3
static void test_round_value_mode_func(double value, int mode, double (*func)(double), int exp)
{
int mode_old;
double rounded;
/* update and check rounding mode */
mode_old = fegetround();
fesetround(mode);
if (fegetround() != mode) e(5);
/* perform rounding */
rounded = func(value);
/* check direction of rounding */
switch (exp)
{
case ROUND_EQ: if (rounded != value) e(6); break;
case ROUND_DN: if (rounded >= value) e(7); break;
case ROUND_UP: if (rounded <= value) e(8); break;
default: assert(0);
}
/* check whether the number is sufficiently close */
if (fabs(value - rounded) >= 1) e(9);
/* check whether the number is integer */
if (remainder(rounded, 1)) e(10);
/* re-check and restore rounding mode */
if (fegetround() != mode) e(11);
fesetround(mode_old);
}
static void test_round_value_mode(double value, int mode, int exp_nearbyint,
int exp_ceil, int exp_floor, int exp_trunc)
{
/* test both nearbyint and trunc */
#if 0
test_round_value_mode_func(value, mode, nearbyint, exp_nearbyint);
#endif
test_round_value_mode_func(value, mode, ceil, exp_ceil);
test_round_value_mode_func(value, mode, floor, exp_floor);
test_round_value_mode_func(value, mode, trunc, exp_trunc);
}
static void test_round_value(double value, int exp_down, int exp_near, int exp_up, int exp_trunc)
{
/* test each rounding mode */
test_round_value_mode(value, FE_DOWNWARD, exp_down, exp_up, exp_down, exp_trunc);
test_round_value_mode(value, FE_TONEAREST, exp_near, exp_up, exp_down, exp_trunc);
test_round_value_mode(value, FE_UPWARD, exp_up, exp_up, exp_down, exp_trunc);
test_round_value_mode(value, FE_TOWARDZERO, exp_trunc, exp_up, exp_down, exp_trunc);
}
static void test_round_values(void)
{
int i;
/* test various values */
for (i = -100000; i < 100000; i++)
{
test_round_value(i + 0.00, ROUND_EQ, ROUND_EQ, ROUND_EQ, ROUND_EQ);
test_round_value(i + 0.25, ROUND_DN, ROUND_DN, ROUND_UP, (i >= 0) ? ROUND_DN : ROUND_UP);
test_round_value(i + 0.50, ROUND_DN, (i % 2) ? ROUND_UP : ROUND_DN, ROUND_UP, (i >= 0) ? ROUND_DN : ROUND_UP);
test_round_value(i + 0.75, ROUND_DN, ROUND_UP, ROUND_UP, (i >= 0) ? ROUND_DN : ROUND_UP);
}
}
static void test_remainder_value(double x, double y)
{
int mode_old;
double r1, r2;
assert(y != 0);
/* compute remainder using the function */
r1 = remainder(x, y);
/* compute remainder using alternative approach */
mode_old = fegetround();
fesetround(FE_TONEAREST);
r2 = x - rint(x / y) * y;
fesetround(mode_old);
/* Compare results */
if (fabs(r1 - r2) > EPSILON && fabs(r1 + r2) > EPSILON)
{
printf("%.20g != %.20g\n", r1, r2);
e(13);
}
}
static void test_remainder_values_y(double x)
{
int i, j;
/* try various rational and transcendental values for y (except zero) */
for (i = -50; i <= 50; i++)
if (i != 0)
for (j = 1; j < 10; j++)
{
test_remainder_value(x, (double) i / (double) j);
test_remainder_value(x, i * M_E + j * M_PI);
}
}
static void test_remainder_values_xy(void)
{
int i, j;
/* try various rational and transcendental values for x */
for (i = -50; i <= 50; i++)
for (j = 1; j < 10; j++)
{
test_remainder_values_y((double) i / (double) j);
test_remainder_values_y(i * M_E + j * M_PI);
}
}
int main(int argc, char **argv)
{
fenv_t fenv;
int i;
start(47);
/* no FPU errors, please */
if (feholdexcept(&fenv) < 0) e(14);
/* some signals count as errors */
for (i = 0; i < _NSIG; i++)
if (i != SIGINT && i != SIGTERM && i != SIGKILL)
signal(i, signal_handler);
/* test various floating point support functions */
test_fpclassify_values();
test_remainder_values_xy();
test_round_values();
quit();
return -1;
}
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