1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 
  22 /*
  23  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  24  */
  25 
  26 /*
  27  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  28  * Use is subject to license terms.
  29  */
  30 
  31 #pragma weak __cexpf = cexpf
  32 
  33 #include "libm.h"
  34 #include "complex_wrapper.h"
  35 
  36 #if defined(__i386) && !defined(__amd64)
  37 extern int __swapRP(int);
  38 #endif
  39 
  40 static const float zero = 0.0F;
  41 
  42 fcomplex
  43 cexpf(fcomplex z)
  44 {
  45         fcomplex ans;
  46         float x, y, c, s;
  47         double t;
  48         int n, ix, iy, hx, hy;
  49 
  50         x = F_RE(z);
  51         y = F_IM(z);
  52         hx = THE_WORD(x);
  53         hy = THE_WORD(y);
  54         ix = hx & 0x7fffffff;
  55         iy = hy & 0x7fffffff;
  56 
  57         if (iy == 0) {                  /* y = 0 */
  58                 F_RE(ans) = expf(x);
  59                 F_IM(ans) = y;
  60         } else if (ix == 0x7f800000) {  /* x is +-inf */
  61                 if (hx < 0) {
  62                         if (iy >= 0x7f800000) {
  63                                 F_RE(ans) = zero;
  64                                 F_IM(ans) = zero;
  65                         } else {
  66                                 sincosf(y, &s, &c);
  67                                 F_RE(ans) = zero * c;
  68                                 F_IM(ans) = zero * s;
  69                         }
  70                 } else {
  71                         if (iy >= 0x7f800000) {
  72                                 F_RE(ans) = x;
  73                                 F_IM(ans) = y - y;
  74                         } else {
  75                                 sincosf(y, &s, &c);
  76                                 F_RE(ans) = x * c;
  77                                 F_IM(ans) = x * s;
  78                         }
  79                 }
  80         } else {
  81                 sincosf(y, &s, &c);
  82 
  83                 if (ix >= 0x42B171AA) {      /* |x| > 88.722... ~ log(2**128) */
  84 #if defined(__i386) && !defined(__amd64)
  85                         int rp = __swapRP(fp_extended);
  86 #endif
  87                         t = __k_cexp(x, &n);
  88                         F_RE(ans) = (float)scalbn(t * (double)c, n);
  89                         F_IM(ans) = (float)scalbn(t * (double)s, n);
  90 #if defined(__i386) && !defined(__amd64)
  91                         if (rp != fp_extended)
  92                                 (void) __swapRP(rp);
  93 #endif
  94                 } else {
  95                         t = expf(x);
  96                         F_RE(ans) = t * c;
  97                         F_IM(ans) = t * s;
  98                 }
  99         }
 100 
 101         return (ans);
 102 }