mirror of
https://github.com/fluencelabs/wasmer
synced 2024-12-13 14:25:32 +00:00
82 lines
3.6 KiB
C
82 lines
3.6 KiB
C
/*
|
|
* Copyright 2016 The Emscripten Authors. All rights reserved.
|
|
* Emscripten is available under two separate licenses, the MIT license and the
|
|
* University of Illinois/NCSA Open Source License. Both these licenses can be
|
|
* found in the LICENSE file.
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <math.h>
|
|
#include <fenv.h>
|
|
|
|
const char *mode(int mode)
|
|
{
|
|
switch(mode)
|
|
{
|
|
case FE_DOWNWARD: return "FE_DOWNWARD";
|
|
case FE_TONEAREST: return "FE_TONEAREST";
|
|
case FE_TOWARDZERO: return "FE_TOWARDZERO";
|
|
case FE_UPWARD: return "FE_UPWARD";
|
|
default: return "Unknown";
|
|
}
|
|
}
|
|
|
|
#define NUMELEMS(x) (sizeof((x)) / sizeof((x)[0]))
|
|
|
|
int main() {
|
|
printf("Initial rounding mode is %s\n", mode(fegetround()));
|
|
|
|
// The functions round() and roundf() are specced to always round *away* from zero (negative numbers down, positive numbers up)
|
|
// fesetround() mode dictates what to do when rounding halfway numbers (-0.5, 0.5, 1.5, 2.5, ...) in functions rint(), rintf(), lrint(), lrintf(), llrint() and llrintf():
|
|
// FE_DOWNWARD always rounds down to the smaller integer.
|
|
// FE_TONEAREST performs banker's rounding (always round towards the even number)
|
|
// FE_TOWARDZERO rounds negative numbers up, and positive numbers down
|
|
// FE_UPWARD always rounds up to the next higher integer.
|
|
// const int modes[] = { FE_DOWNWARD, FE_TONEAREST, FE_TOWARDZERO, FE_UPWARD }; // TODO: Currently only supported mode is FE_TONEAREST.
|
|
const int modes[] = { FE_TONEAREST };
|
|
const double interestingDoubles[] = { -4.5, -3.6, -3.5, -3.4, -2.6, -2.5, -2.4, -1.5, -0.5, 0, 0.5, 1.4, 1.5, 1.6, 2.5, 3.5, 4.5 };
|
|
const float interestingFloats[] = { -4.5f, -3.6f, -3.5f, -3.4f, -2.6f, -2.5f, -2.4f, -1.5f, -0.5f, 0, 0.5f, 1.4f, 1.5f, 1.6f, 2.5f, 3.5f, 4.5f };
|
|
|
|
for(int i = 0; i < NUMELEMS(modes); ++i)
|
|
{
|
|
int ret = fesetround(modes[i]);
|
|
int modeAfter = fegetround();
|
|
printf("fesetround(%s) returned %d, fegetround() afterwards returns %s. Test results:\n", mode(modes[i]), ret, mode(modeAfter));
|
|
|
|
for(int j = 0; j < NUMELEMS(interestingDoubles); ++j)
|
|
printf("%s: round(%.1f)=%.1f\n", mode(modeAfter), interestingDoubles[j], round(interestingDoubles[j]));
|
|
|
|
for(int j = 0; j < NUMELEMS(interestingFloats); ++j)
|
|
printf("%s: roundf(%.1f)=%.1f\n", mode(modeAfter), interestingFloats[j], roundf(interestingFloats[j]));
|
|
|
|
for(int j = 0; j < NUMELEMS(interestingDoubles); ++j)
|
|
printf("%s: rint(%.1f)=%.1f\n", mode(modeAfter), interestingDoubles[j], rint(interestingDoubles[j]));
|
|
|
|
for(int j = 0; j < NUMELEMS(interestingDoubles); ++j)
|
|
printf("%s: rintf(%.1f)=%.1f\n", mode(modeAfter), interestingFloats[j], rint(interestingFloats[j]));
|
|
|
|
for(int j = 0; j < NUMELEMS(interestingDoubles); ++j)
|
|
printf("%s: lrint(%.1f)=%ld\n", mode(modeAfter), interestingDoubles[j], lrint(interestingDoubles[j]));
|
|
|
|
for(int j = 0; j < NUMELEMS(interestingDoubles); ++j)
|
|
printf("%s: lrintf(%.1f)=%ld\n", mode(modeAfter), interestingFloats[j], lrintf(interestingFloats[j]));
|
|
|
|
for(int j = 0; j < NUMELEMS(interestingDoubles); ++j)
|
|
printf("%s: llrint(%.1f)=%lld\n", mode(modeAfter), interestingDoubles[j], llrint(interestingDoubles[j]));
|
|
|
|
for(int j = 0; j < NUMELEMS(interestingDoubles); ++j)
|
|
printf("%s: llrintf(%.1f)=%lld\n", mode(modeAfter), interestingFloats[j], llrintf(interestingFloats[j]));
|
|
}
|
|
|
|
double param, fractpart, intpart;
|
|
|
|
param = 3.14159265;
|
|
fractpart = modf (param , &intpart);
|
|
printf ("%f = %f + %f\n", param, intpart, fractpart);
|
|
|
|
param = -3.14159265;
|
|
fractpart = modf (param , &intpart);
|
|
printf ("%f = %f + %f\n", param, intpart, fractpart);
|
|
return 0;
|
|
}
|