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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
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*
* 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.
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package com.oracle.svm.core.graal.amd64;
import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.ILLEGAL;
import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.REG;
import org.graalvm.compiler.asm.Label;
import org.graalvm.compiler.asm.amd64.AMD64Address;
import org.graalvm.compiler.asm.amd64.AMD64Assembler.ConditionFlag;
import org.graalvm.compiler.asm.amd64.AMD64MacroAssembler;
import org.graalvm.compiler.lir.LIRInstructionClass;
import org.graalvm.compiler.lir.Opcode;
import org.graalvm.compiler.lir.amd64.AMD64BlockEndOp;
import org.graalvm.compiler.lir.asm.CompilationResultBuilder;
import com.oracle.svm.core.FrameAccess;
import com.oracle.svm.core.SubstrateOptions;
import jdk.vm.ci.amd64.AMD64;
import jdk.vm.ci.code.ValueUtil;
import jdk.vm.ci.meta.AllocatableValue;
@Opcode("FAR_RETURN")
public final class AMD64FarReturnOp extends AMD64BlockEndOp {
public static final LIRInstructionClass<AMD64FarReturnOp> TYPE = LIRInstructionClass.create(AMD64FarReturnOp.class);
@Use({REG, ILLEGAL}) AllocatableValue result;
@Use(REG) AllocatableValue sp;
@Use(REG) AllocatableValue ip;
private final boolean fromMethodWithCalleeSavedRegisters;
public AMD64FarReturnOp(AllocatableValue result, AllocatableValue sp, AllocatableValue ip, boolean fromMethodWithCalleeSavedRegisters) {
super(TYPE);
this.result = result;
this.sp = sp;
this.ip = ip;
this.fromMethodWithCalleeSavedRegisters = fromMethodWithCalleeSavedRegisters;
}
@Override
public void emitCode(CompilationResultBuilder crb, AMD64MacroAssembler masm) {
if (SubstrateOptions.PreserveFramePointer.getValue()) {
/*
* We need to properly restore RBP to the value that matches the frame of the new stack
* pointer. Two options: 1) When RSP is not changing, we are jumping within the same
* frame - no adjustment of RBP necessary. 2) We jump to a frame earlier in the stack -
* the corresponding RBP value was spilled to the stack by the callee.
*/
Label done = new Label();
masm.cmpqAndJcc(AMD64.rsp, ValueUtil.asRegister(sp), ConditionFlag.Equal, done, true);
/*
* The callee pushes two word-sized values: first the return address, then the saved
* RBP. The stack grows downwards, so the offset is negative relative to the new stack
* pointer.
*/
masm.movq(AMD64.rbp, new AMD64Address(ValueUtil.asRegister(sp), -(FrameAccess.returnAddressSize() + FrameAccess.singleton().savedBasePointerSize())));
masm.bind(done);
}
masm.movq(AMD64.rsp, ValueUtil.asRegister(sp));
if (fromMethodWithCalleeSavedRegisters) {
/*
* Restoring the callee saved registers is going to overwrite the register that holds
* the new instruction pointern (ip). We therefore spill the new ip to the stack, and do
* the indirect jump with an address operand to avoid a temporary register.
*/
AMD64Address ipAddress = new AMD64Address(AMD64.rsp, -FrameAccess.returnAddressSize());
masm.movq(ipAddress, ValueUtil.asRegister(ip));
AMD64CalleeSavedRegisters.singleton().emitRestore(masm, 0, ValueUtil.asRegister(result));
masm.jmp(ipAddress);
} else {
masm.jmp(ValueUtil.asRegister(ip));
}
}
}