1 /*
   2  * Copyright (c) 2013, 2016, 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.aarch64;
  24 
  25 import static org.graalvm.compiler.hotspot.HotSpotBackend.UNWIND_EXCEPTION_TO_CALLER;
  26 import static jdk.vm.ci.aarch64.AArch64.lr;
  27 import static jdk.vm.ci.code.ValueUtil.asRegister;
  28 
  29 import org.graalvm.compiler.asm.aarch64.AArch64MacroAssembler;
  30 import org.graalvm.compiler.core.common.spi.ForeignCallLinkage;
  31 import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig;
  32 import org.graalvm.compiler.hotspot.stubs.UnwindExceptionToCallerStub;
  33 import org.graalvm.compiler.lir.LIRInstructionClass;
  34 import org.graalvm.compiler.lir.Opcode;
  35 import org.graalvm.compiler.lir.aarch64.AArch64Call;
  36 import org.graalvm.compiler.lir.asm.CompilationResultBuilder;
  37 
  38 import jdk.vm.ci.code.CallingConvention;
  39 import jdk.vm.ci.code.Register;
  40 import jdk.vm.ci.code.RegisterValue;
  41 
  42 /**
  43  * Removes the current frame and jumps to the {@link UnwindExceptionToCallerStub}.
  44  */
  45 @Opcode("UNWIND")
  46 public final class AArch64HotSpotUnwindOp extends AArch64HotSpotEpilogueOp {
  47     public static final LIRInstructionClass<AArch64HotSpotUnwindOp> TYPE = LIRInstructionClass.create(AArch64HotSpotUnwindOp.class);
  48 
  49     @Use protected RegisterValue exception;
  50 
  51     public AArch64HotSpotUnwindOp(GraalHotSpotVMConfig config, RegisterValue exception) {
  52         super(TYPE, config);
  53         this.exception = exception;
  54     }
  55 
  56     @Override
  57     public void emitCode(CompilationResultBuilder crb, AArch64MacroAssembler masm) {
  58         leaveFrame(crb, masm, /* emitSafepoint */false);
  59 
  60         ForeignCallLinkage linkage = crb.foreignCalls.lookupForeignCall(UNWIND_EXCEPTION_TO_CALLER);
  61         CallingConvention cc = linkage.getOutgoingCallingConvention();
  62         assert cc.getArgumentCount() == 2;
  63         assert exception.equals(cc.getArgument(0));
  64 
  65         // Get return address (is in lr after frame leave)
  66         Register returnAddress = asRegister(cc.getArgument(1));
  67         masm.movx(returnAddress, lr);
  68 
  69         AArch64Call.directJmp(crb, masm, linkage);
  70     }
  71 }