Last change
on this file since 403 was 337, checked in by coas-nagasima, 6 years ago |
ASP3版ECNLを追加
|
-
Property svn:eol-style
set to
native
-
Property svn:mime-type
set to
text/x-csrc;charset=UTF-8
|
File size:
653 bytes
|
Line | |
---|
1 | #include "libm.h"
|
---|
2 |
|
---|
3 | #if FLT_EVAL_METHOD==0 || FLT_EVAL_METHOD==1
|
---|
4 | #define EPS DBL_EPSILON
|
---|
5 | #elif FLT_EVAL_METHOD==2
|
---|
6 | #define EPS LDBL_EPSILON
|
---|
7 | #endif
|
---|
8 | static const double_t toint = 1/EPS;
|
---|
9 |
|
---|
10 | double floor(double x)
|
---|
11 | {
|
---|
12 | union {double f; uint64_t i;} u = {x};
|
---|
13 | int e = u.i >> 52 & 0x7ff;
|
---|
14 | double_t y;
|
---|
15 |
|
---|
16 | if (e >= 0x3ff+52 || x == 0)
|
---|
17 | return x;
|
---|
18 | /* y = int(x) - x, where int(x) is an integer neighbor of x */
|
---|
19 | if (u.i >> 63)
|
---|
20 | y = x - toint + toint - x;
|
---|
21 | else
|
---|
22 | y = x + toint - toint - x;
|
---|
23 | /* special case because of non-nearest rounding modes */
|
---|
24 | if (e <= 0x3ff-1) {
|
---|
25 | FORCE_EVAL(y);
|
---|
26 | return u.i >> 63 ? -1 : 0;
|
---|
27 | }
|
---|
28 | if (y > 0)
|
---|
29 | return x + y - 1;
|
---|
30 | return x + y;
|
---|
31 | }
|
---|
Note:
See
TracBrowser
for help on using the repository browser.