1 /*
   2  * Copyright (c) 2015, 2017, 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 package org.graalvm.compiler.hotspot.sparc;
  24 
  25 import static jdk.vm.ci.code.ValueUtil.asRegister;
  26 import static jdk.vm.ci.sparc.SPARC.g0;
  27 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.BPCC;
  28 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.CBCOND;
  29 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.INSTRUCTION_SIZE;
  30 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.Annul.ANNUL;
  31 import static org.graalvm.compiler.asm.sparc.SPARCAssembler.BranchPredict.PREDICT_TAKEN;
  32 import static org.graalvm.compiler.lir.sparc.SPARCMove.loadFromConstantTable;
  33 
  34 import org.graalvm.compiler.asm.Assembler.LabelHint;
  35 import org.graalvm.compiler.asm.Label;
  36 import org.graalvm.compiler.asm.sparc.SPARCAssembler.CC;
  37 import org.graalvm.compiler.asm.sparc.SPARCAssembler.ConditionFlag;
  38 import org.graalvm.compiler.asm.sparc.SPARCMacroAssembler;
  39 import org.graalvm.compiler.core.common.calc.Condition;
  40 import org.graalvm.compiler.lir.LIRInstructionClass;
  41 import org.graalvm.compiler.lir.LabelRef;
  42 import org.graalvm.compiler.lir.SwitchStrategy;
  43 import org.graalvm.compiler.lir.Variable;
  44 import org.graalvm.compiler.lir.asm.CompilationResultBuilder;
  45 import org.graalvm.compiler.lir.sparc.SPARCControlFlow;
  46 import org.graalvm.compiler.lir.sparc.SPARCDelayedControlTransfer;
  47 
  48 import jdk.vm.ci.code.Register;
  49 import jdk.vm.ci.hotspot.HotSpotMetaspaceConstant;
  50 import jdk.vm.ci.meta.AllocatableValue;
  51 import jdk.vm.ci.meta.Constant;
  52 import jdk.vm.ci.meta.Value;
  53 import jdk.vm.ci.sparc.SPARC.CPUFeature;
  54 
  55 final class SPARCHotSpotStrategySwitchOp extends SPARCControlFlow.StrategySwitchOp {
  56     public static final LIRInstructionClass<SPARCHotSpotStrategySwitchOp> TYPE = LIRInstructionClass.create(SPARCHotSpotStrategySwitchOp.class);
  57 
  58     SPARCHotSpotStrategySwitchOp(Value constantTableBase, SwitchStrategy strategy, LabelRef[] keyTargets, LabelRef defaultTarget, AllocatableValue key, Variable scratch) {
  59         super(TYPE, constantTableBase, strategy, keyTargets, defaultTarget, key, scratch);
  60     }
  61 
  62     public class HotSpotSwitchClosure extends SwitchClosure {
  63         protected HotSpotSwitchClosure(Register keyRegister, Register constantBaseRegister, CompilationResultBuilder crb, SPARCMacroAssembler masm) {
  64             super(keyRegister, constantBaseRegister, crb, masm);
  65         }
  66 
  67         @Override
  68         protected void conditionalJump(int index, Condition condition, Label target) {
  69             if (keyConstants[index] instanceof HotSpotMetaspaceConstant) {
  70                 HotSpotMetaspaceConstant constant = (HotSpotMetaspaceConstant) keyConstants[index];
  71                 CC conditionCode = constant.isCompressed() ? CC.Icc : CC.Xcc;
  72                 ConditionFlag conditionFlag = SPARCControlFlow.fromCondition(true, condition, false);
  73                 LabelHint hint = requestHint(masm, target);
  74 
  75                 // Load constant takes one instruction
  76                 int cbCondPosition = masm.position() + INSTRUCTION_SIZE;
  77                 boolean canUseShortBranch = masm.hasFeature(CPUFeature.CBCOND) && SPARCControlFlow.isShortBranch(masm, cbCondPosition, hint, target);
  78 
  79                 Register scratchRegister = asRegister(scratch);
  80                 loadFromConstantTable(crb, masm, asRegister(constantTableBase), constant, scratchRegister, SPARCDelayedControlTransfer.DUMMY);
  81 
  82                 if (canUseShortBranch) {
  83                     CBCOND.emit(masm, conditionFlag, conditionCode == CC.Xcc, keyRegister, scratchRegister, target);
  84                 } else {
  85                     masm.cmp(keyRegister, scratchRegister);
  86                     BPCC.emit(masm, conditionCode, conditionFlag, ANNUL, PREDICT_TAKEN, target);
  87                     masm.nop();  // delay slot
  88                 }
  89             } else {
  90                 super.conditionalJump(index, condition, target);
  91             }
  92         }
  93     }
  94 
  95     @Override
  96     protected int estimateEmbeddedSize(Constant c) {
  97         if (c instanceof HotSpotMetaspaceConstant) {
  98             return ((HotSpotMetaspaceConstant) c).isCompressed() ? 4 : 8;
  99         } else {
 100             return super.estimateEmbeddedSize(c);
 101         }
 102     }
 103 
 104     @Override
 105     public void emitCode(final CompilationResultBuilder crb, final SPARCMacroAssembler masm) {
 106         final Register keyRegister = asRegister(key);
 107         final Register constantBaseRegister = AllocatableValue.ILLEGAL.equals(constantTableBase) ? g0 : asRegister(constantTableBase);
 108         strategy.run(new HotSpotSwitchClosure(keyRegister, constantBaseRegister, crb, masm));
 109     }
 110 }