1 /* 2 * Copyright 2002 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 20 * CA 95054 USA or visit www.sun.com if you need additional information or 21 * have any questions. 22 * 23 */ 24 25 package sun.jvm.hotspot.asm.sparc; 26 27 import sun.jvm.hotspot.asm.*; 28 29 abstract class V9RegisterBranchDecoder extends V9BranchDecoder { 30 static int getDisp16(int instruction) { 31 int offset = (DISP_16_LO_MASK & instruction) | 32 ((DISP_16_HI_MASK & instruction) >>> (DISP_16_HI_START_BIT - DISP_16_LO_NUMBITS)); 33 34 // sign extend and word align 35 offset = extractSignedIntFromNBits(offset, 16); 36 offset <<= 2; 37 38 return offset; 39 } 40 41 String getConditionName(int conditionCode, boolean isAnnuled) { 42 return null; 43 } 44 45 abstract String getRegisterConditionName(int rcond); 46 47 public Instruction decode(int instruction, SPARCInstructionFactory factory) { 48 SPARCV9InstructionFactory v9factory = (SPARCV9InstructionFactory) factory; 49 int rcond = (BRANCH_RCOND_MASK & instruction) >>> BRANCH_RCOND_START_BIT; 50 if (rcond == BRANCH_RCOND_RESERVED1 || rcond == BRANCH_RCOND_RESERVED2) 51 return factory.newIllegalInstruction(instruction); 52 53 SPARCRegister rs1 = SPARCRegisters.getRegister(getSourceRegister1(instruction)); 54 boolean predictTaken = getPredictTaken(instruction); 55 boolean annuled = getAnnuledBit(instruction); 56 PCRelativeAddress addr = new PCRelativeAddress(getDisp16(instruction)); 57 String name = getRegisterConditionName(rcond); 58 return v9factory.newV9RegisterBranchInstruction(name, addr, annuled, rcond, rs1, predictTaken); 59 } 60 }