SDL  2.0
s_floor.c File Reference
#include "math_libm.h"
#include "math_private.h"
+ Include dependency graph for s_floor.c:

Go to the source code of this file.

Functions

double floor (double x)
 

Variables

static const double huge = 1.0e300
 

Function Documentation

◆ floor()

double floor ( double  x)

Definition at line 33 of file s_floor.c.

34 {
35  int32_t i0,i1,j0;
36  u_int32_t i,j;
37  EXTRACT_WORDS(i0,i1,x);
38  j0 = ((i0>>20)&0x7ff)-0x3ff;
39  if(j0<20) {
40  if(j0<0) { /* raise inexact if x != 0 */
41  if(huge+x>0.0) {/* return 0*sign(x) if |x|<1 */
42  if(i0>=0) {i0=i1=0;}
43  else if(((i0&0x7fffffff)|i1)!=0)
44  { i0=0xbff00000;i1=0;}
45  }
46  } else {
47  i = (0x000fffff)>>j0;
48  if(((i0&i)|i1)==0) return x; /* x is integral */
49  if(huge+x>0.0) { /* raise inexact flag */
50  if(i0<0) i0 += (0x00100000)>>j0;
51  i0 &= (~i); i1=0;
52  }
53  }
54  } else if (j0>51) {
55  if(j0==0x400) return x+x; /* inf or NaN */
56  else return x; /* x is integral */
57  } else {
58  i = ((u_int32_t)(0xffffffff))>>(j0-20);
59  if((i1&i)==0) return x; /* x is integral */
60  if(huge+x>0.0) { /* raise inexact flag */
61  if(i0<0) {
62  if(j0==20) i0+=1;
63  else {
64  j = i1+(1<<(52-j0));
65  if(j<(u_int32_t)i1) i0 +=1 ; /* got a carry */
66  i1=j;
67  }
68  }
69  i1 &= (~i);
70  }
71  }
72  INSERT_WORDS(x,i0,i1);
73  return x;
74 }

References EXTRACT_WORDS, huge, i, i1, INSERT_WORDS, and j.

Referenced by __kernel_rem_pio2(), and SDL_floor().

Variable Documentation

◆ huge

const double huge = 1.0e300
static

Definition at line 31 of file s_floor.c.

Referenced by floor().

i1
const GLubyte GLuint GLuint GLuint GLuint alpha GLboolean GLboolean GLboolean GLboolean alpha GLint GLint GLsizei GLsizei GLenum type GLenum GLint GLenum GLint GLint GLsizei GLsizei GLint border GLenum GLint GLint GLint GLint GLint GLsizei GLsizei height GLsizei GLsizei GLenum GLenum const GLvoid *pixels GLenum GLint i1
Definition: SDL_glfuncs.h:141
EXTRACT_WORDS
#define EXTRACT_WORDS(ix0, ix1, d)
Definition: math_private.h:99
x
GLint GLint GLint GLint GLint x
Definition: SDL_opengl.h:1574
int32_t
signed int int32_t
Definition: SDL_config_windows.h:62
u_int32_t
unsigned int u_int32_t
Definition: math_private.h:31
huge
static const double huge
Definition: s_floor.c:31
INSERT_WORDS
#define INSERT_WORDS(d, ix0, ix1)
Definition: math_private.h:127
j
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int int in j)
Definition: SDL_x11sym.h:50
i
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:50