1 /*
   2  * Copyright (c) 1999, 2008, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include <byteswap.h>
  26 
  27 // Efficient swapping of data bytes from Java byte
  28 // ordering to native byte ordering and vice versa.
  29 inline u2   Bytes::swap_u2(u2 x) {
  30 #ifdef AMD64
  31   return bswap_16(x);
  32 #else
  33   u2 ret;
  34   __asm__ __volatile__ (
  35     "movw %0, %%ax;"
  36     "xchg %%al, %%ah;"
  37     "movw %%ax, %0"
  38     :"=r" (ret)      // output : register 0 => ret
  39     :"0"  (x)        // input  : x => register 0
  40     :"ax", "0"       // clobbered registers
  41   );
  42   return ret;
  43 #endif // AMD64
  44 }
  45 
  46 inline u4   Bytes::swap_u4(u4 x) {
  47 #ifdef AMD64
  48   return bswap_32(x);
  49 #else
  50   u4 ret;
  51   __asm__ __volatile__ (
  52     "bswap %0"
  53     :"=r" (ret)      // output : register 0 => ret
  54     :"0"  (x)        // input  : x => register 0
  55     :"0"             // clobbered register
  56   );
  57   return ret;
  58 #endif // AMD64
  59 }
  60 
  61 #ifdef AMD64
  62 inline u8 Bytes::swap_u8(u8 x) {
  63 #ifdef SPARC_WORKS
  64   // workaround for SunStudio12 CR6615391
  65   __asm__ __volatile__ (
  66     "bswapq %0"
  67     :"=r" (x)        // output : register 0 => x
  68     :"0"  (x)        // input  : x => register 0
  69     :"0"             // clobbered register
  70   );
  71   return x;
  72 #else
  73   return bswap_64(x);
  74 #endif
  75 }
  76 #else
  77 // Helper function for swap_u8
  78 inline u8   Bytes::swap_u8_base(u4 x, u4 y) {
  79   return (((u8)swap_u4(x))<<32) | swap_u4(y);
  80 }
  81 
  82 inline u8 Bytes::swap_u8(u8 x) {
  83   return swap_u8_base(*(u4*)&x, *(((u4*)&x)+1));
  84 }
  85 #endif // !AMD64