1 /*
   2  * Copyright (c) 1998, 2010, 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 #ifndef OS_CPU_SOLARIS_X86_VM_BYTES_SOLARIS_X86_INLINE_HPP
  26 #define OS_CPU_SOLARIS_X86_VM_BYTES_SOLARIS_X86_INLINE_HPP
  27 
  28 // For Sun Studio - implementation is in solaris_i486.il.
  29 // For gcc - implementation is just below.
  30 extern "C" u2 _raw_swap_u2(u2 x);
  31 extern "C" u4 _raw_swap_u4(u4 x);
  32 #ifdef AMD64
  33 extern "C" u8 _raw_swap_u8(u8 x);
  34 #else
  35 extern "C" u8 _raw_swap_u8(u4 x, u4 y);
  36 #endif // AMD64
  37 
  38 // Efficient swapping of data bytes from Java byte
  39 // ordering to native byte ordering and vice versa.
  40 inline u2   Bytes::swap_u2(u2 x) {
  41   return _raw_swap_u2(x);
  42 }
  43 
  44 inline u4   Bytes::swap_u4(u4 x) {
  45   return _raw_swap_u4(x);
  46 }
  47 
  48 inline u8   Bytes::swap_u8(u8 x) {
  49 #ifdef AMD64
  50   return _raw_swap_u8(x);
  51 #else
  52   return swap_u8_base(*(u4*)&x, *(((u4*)&x)+1));
  53 #endif // AMD64
  54 
  55 }
  56 
  57 #ifndef AMD64
  58 // Helper function for swap_u8
  59 inline u8   Bytes::swap_u8_base(u4 x, u4 y) {
  60   return _raw_swap_u8(x, y);
  61 }
  62 #endif // !AMD64
  63 
  64 
  65 #ifdef _GNU_SOURCE
  66 
  67 extern "C" {
  68 #ifdef AMD64
  69   inline u2 _raw_swap_u2(u2 x) {
  70     register unsigned short int __dest;
  71     __asm__ ("rorw $8, %w0": "=r" (__dest): "0" (x): "cc");
  72     return __dest;
  73   }
  74   inline u4 _raw_swap_u4(u4 x) {
  75     register unsigned int __dest;
  76     __asm__ ("bswap %0" : "=r" (__dest) : "0" (x));
  77     return __dest;
  78   }
  79   inline u8 _raw_swap_u8(u8 x) {
  80     register unsigned long  __dest;
  81     __asm__ ("bswap %q0" : "=r" (__dest) : "0" (x));
  82     return __dest;
  83   }
  84 #else
  85   inline u2 _raw_swap_u2(u2 x) {
  86     u2 ret;
  87     __asm__ __volatile__ (
  88       "movw %0, %%ax;"
  89       "xchg %%al, %%ah;"
  90       "movw %%ax, %0"
  91       :"=r" (ret)      // output : register 0 => ret
  92       :"0"  (x)        // input  : x => register 0
  93       :"ax", "0"       // clobbered registers
  94     );
  95     return ret;
  96   }
  97 
  98   inline u4 _raw_swap_u4(u4 x) {
  99     u4 ret;
 100     __asm__ __volatile__ (
 101       "bswap %0"
 102       :"=r" (ret)      // output : register 0 => ret
 103       :"0"  (x)        // input  : x => register 0
 104       :"0"             // clobbered register
 105     );
 106     return ret;
 107   }
 108 
 109   inline u8 _raw_swap_u8(u4 x, u4 y) {
 110     return (((u8)_raw_swap_u4(x))<<32) | _raw_swap_u4(y);
 111   }
 112 #endif // AMD64
 113 }
 114 #endif  //_GNU_SOURCE
 115 
 116 #endif // OS_CPU_SOLARIS_X86_VM_BYTES_SOLARIS_X86_INLINE_HPP