hotspot/src/cpu/zero/vm/bytes_zero.hpp
changeset 4013 b154310845de
child 5547 f4b087cbb361
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/cpu/zero/vm/bytes_zero.hpp	Tue Oct 13 12:04:21 2009 -0700
@@ -0,0 +1,164 @@
+/*
+ * Copyright 1997-2002 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 2007, 2008, 2009 Red Hat, Inc.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+typedef union unaligned {
+  u4 u;
+  u2 us;
+  u8 ul;
+} __attribute__((packed)) unaligned;
+
+class Bytes: AllStatic {
+ public:
+  // Returns true if the byte ordering used by Java is different
+  // from the native byte ordering of the underlying machine.
+  static inline bool is_Java_byte_ordering_different() {
+#ifdef VM_LITTLE_ENDIAN
+    return true;
+#else
+    return false;
+#endif
+  }
+
+  // Efficient reading and writing of unaligned unsigned data in
+  // platform-specific byte ordering.
+  static inline u2 get_native_u2(address p){
+    unaligned *up = (unaligned *) p;
+    return up->us;
+  }
+
+  static inline u4 get_native_u4(address p) {
+    unaligned *up = (unaligned *) p;
+    return up->u;
+  }
+
+  static inline u8 get_native_u8(address p) {
+    unaligned *up = (unaligned *) p;
+    return up->ul;
+  }
+
+  static inline void put_native_u2(address p, u2 x) {
+    unaligned *up = (unaligned *) p;
+    up->us = x;
+  }
+
+  static inline void put_native_u4(address p, u4 x) {
+    unaligned *up = (unaligned *) p;
+    up->u = x;
+  }
+
+  static inline void put_native_u8(address p, u8 x) {
+    unaligned *up = (unaligned *) p;
+    up->ul = x;
+  }
+
+  // Efficient reading and writing of unaligned unsigned data in Java
+  // byte ordering (i.e. big-endian ordering).
+#ifdef VM_LITTLE_ENDIAN
+  // Byte-order reversal is needed
+  static inline u2 get_Java_u2(address p) {
+    return (u2(p[0]) << 8) |
+           (u2(p[1])     );
+  }
+  static inline u4 get_Java_u4(address p) {
+    return (u4(p[0]) << 24) |
+           (u4(p[1]) << 16) |
+           (u4(p[2]) <<  8) |
+           (u4(p[3])      );
+  }
+  static inline u8 get_Java_u8(address p) {
+    u4 hi, lo;
+    hi = (u4(p[0]) << 24) |
+         (u4(p[1]) << 16) |
+         (u4(p[2]) <<  8) |
+         (u4(p[3])      );
+    lo = (u4(p[4]) << 24) |
+         (u4(p[5]) << 16) |
+         (u4(p[6]) <<  8) |
+         (u4(p[7])      );
+    return u8(lo) | (u8(hi) << 32);
+  }
+
+  static inline void put_Java_u2(address p, u2 x) {
+    p[0] = x >> 8;
+    p[1] = x;
+  }
+  static inline void put_Java_u4(address p, u4 x) {
+    p[0] = x >> 24;
+    p[1] = x >> 16;
+    p[2] = x >> 8;
+    p[3] = x;
+  }
+  static inline void put_Java_u8(address p, u8 x) {
+    u4 hi, lo;
+    lo = x;
+    hi = x >> 32;
+    p[0] = hi >> 24;
+    p[1] = hi >> 16;
+    p[2] = hi >> 8;
+    p[3] = hi;
+    p[4] = lo >> 24;
+    p[5] = lo >> 16;
+    p[6] = lo >> 8;
+    p[7] = lo;
+  }
+
+  // Efficient swapping of byte ordering
+  static inline u2 swap_u2(u2 x);
+  static inline u4 swap_u4(u4 x);
+  static inline u8 swap_u8(u8 x);
+#else
+  // No byte-order reversal is needed
+  static inline u2 get_Java_u2(address p) {
+    return get_native_u2(p);
+  }
+  static inline u4 get_Java_u4(address p) {
+    return get_native_u4(p);
+  }
+  static inline u8 get_Java_u8(address p) {
+    return get_native_u8(p);
+  }
+
+  static inline void put_Java_u2(address p, u2 x) {
+    put_native_u2(p, x);
+  }
+  static inline void put_Java_u4(address p, u4 x) {
+    put_native_u4(p, x);
+  }
+  static inline void put_Java_u8(address p, u8 x) {
+    put_native_u8(p, x);
+  }
+
+  // No byte-order reversal is needed
+  static inline u2 swap_u2(u2 x) { return x; }
+  static inline u4 swap_u4(u4 x) { return x; }
+  static inline u8 swap_u8(u8 x) { return x; }
+#endif // VM_LITTLE_ENDIAN
+};
+
+#ifdef VM_LITTLE_ENDIAN
+// The following header contains the implementations of swap_u2,
+// swap_u4, and swap_u8
+#include "incls/_bytes_pd.inline.hpp.incl"
+#endif // VM_LITTLE_ENDIAN