Mercurial > hg > truffle
view agent/src/share/classes/sun/jvm/hotspot/asm/sparc/RegisterDecoder.java @ 3945:8ed53447f690
Merge
author | iveresov |
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date | Thu, 15 Sep 2011 12:44:09 -0700 |
parents | c18cbe5936b8 |
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/* * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved. * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ package sun.jvm.hotspot.asm.sparc; import sun.jvm.hotspot.asm.RTLDataTypes; class RegisterDecoder implements /* imports */ RTLDataTypes { // refer to page 40 - section 5.1.4.1 - Floating-point Register Number Encoding private static SPARCFloatRegister decodeDouble(int num) { // 6 bit double precision registers are encoded in 5 bits as // b<4> b<3> b<2> b<1> b<5>. boolean lsb = (0x1 & num) != 0; if (lsb) num |= 0x20; // 10000b if ((num % 2) != 0) return null; return SPARCFloatRegisters.getRegister(num); } private static SPARCFloatRegister decodeQuad(int num) { // 6 bit quad precision registers are encoded in 5 bits as // b<4> b<3> b<2> 0 b<5> boolean lsb = (0x1 & num) != 0; if (lsb) num |= 0x20; // 10000b if ((num % 4) != 0) return null; return SPARCFloatRegisters.getRegister(num); } static SPARCRegister decode(int dataType, int regNum) { regNum &= 0x1F; // mask out all but lsb 5 bits SPARCRegister result = null; switch (dataType) { case RTLDT_FL_SINGLE: result = SPARCFloatRegisters.getRegister(regNum); break; case RTLDT_FL_DOUBLE: result = decodeDouble(regNum); break; case RTLDT_FL_QUAD: result = decodeQuad(regNum); break; case RTLDT_UNKNOWN: result = null; break; default: // some integer register result = SPARCRegisters.getRegister(regNum); break; } return result; } }