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  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  23  */
  24 /*
  25  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  26  * Use is subject to license terms.
  27  */
  28 
  29 #pragma weak cexpf = __cexpf
  30 
  31 #include "libm.h"
  32 #include "complex_wrapper.h"
  33 
  34 #if defined(__i386) && !defined(__amd64)
  35 extern int __swapRP(int);
  36 #endif
  37 
  38 static const float zero = 0.0F;
  39 
  40 fcomplex
  41 cexpf(fcomplex z) {
  42         fcomplex        ans;
  43         float           x, y, c, s;
  44         double          t;
  45         int             n, ix, iy, hx, hy;
  46 
  47         x = F_RE(z);
  48         y = F_IM(z);
  49         hx = THE_WORD(x);
  50         hy = THE_WORD(y);
  51         ix = hx & 0x7fffffff;
  52         iy = hy & 0x7fffffff;
  53         if (iy == 0) {          /* y = 0 */
  54                 F_RE(ans) = expf(x);
  55                 F_IM(ans) = y;
  56         } else if (ix == 0x7f800000) {  /* x is +-inf */
  57                 if (hx < 0) {
  58                         if (iy >= 0x7f800000) {
  59                                 F_RE(ans) = zero;
  60                                 F_IM(ans) = zero;
  61                         } else {
  62                                 sincosf(y, &s, &c);
  63                                 F_RE(ans) = zero * c;
  64                                 F_IM(ans) = zero * s;
  65                         }
  66                 } else {
  67                         if (iy >= 0x7f800000) {
  68                                 F_RE(ans) = x;
  69                                 F_IM(ans) = y - y;
  70                         } else {
  71                                 sincosf(y, &s, &c);
  72                                 F_RE(ans) = x * c;
  73                                 F_IM(ans) = x * s;
  74                         }
  75                 }
  76         } else {
  77                 sincosf(y, &s, &c);
  78                 if (ix >= 0x42B171AA) {      /* |x| > 88.722... ~ log(2**128) */
  79 #if defined(__i386) && !defined(__amd64)
  80                         int     rp = __swapRP(fp_extended);
  81 #endif
  82                         t = __k_cexp(x, &n);
  83                         F_RE(ans) = (float)scalbn(t * (double)c, n);
  84                         F_IM(ans) = (float)scalbn(t * (double)s, n);
  85 #if defined(__i386) && !defined(__amd64)
  86                         if (rp != fp_extended)
  87                                 (void) __swapRP(rp);
  88 #endif
  89                 } else {
  90                         t = expf(x);
  91                         F_RE(ans) = t * c;
  92                         F_IM(ans) = t * s;
  93                 }
  94         }
  95         return (ans);
  96 }