VirtualGuardRuntime.cpp

/*******************************************************************************
 * Copyright (c) 2021, 2021 IBM Corp. and others
 *
 * This program and the accompanying materials are made available under
 * the terms of the Eclipse Public License 2.0 which accompanies this
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 * or the Apache License, Version 2.0 which accompanies this distribution
 * and is available at https://www.apache.org/licenses/LICENSE-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License, v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception [1] and GNU General Public
 * License, version 2 with the OpenJDK Assembly Exception [2].
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 * [1] https://www.gnu.org/software/classpath/license.html
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 * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0 WITH Classpath-exception-2.0 OR LicenseRef-GPL-2.0 WITH Assembly-exception
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#include <stdint.h>
#include "codegen/RVInstruction.hpp"
#include "codegen/InstOpCode.hpp"
#include "env/CompilerEnv.hpp"
#include "env/jittypes.h"
#include <infra/Assert.hpp>

extern void riscvCodeSync(unsigned char *codeStart, unsigned int codeSize);

extern "C" void _patchVirtualGuard(uint8_t *locationAddr, uint8_t *destinationAddr, int32_t smpFlag)
   {
   int64_t distance = (int64_t)destinationAddr - (int64_t)locationAddr;
   *(uint32_t *)locationAddr = TR_RISCV_UJTYPE(TR::InstOpCode::getOpCodeBinaryEncoding(TR::InstOpCode::_jal), 0, distance);
   riscvCodeSync((unsigned char *)locationAddr, RISCV_INSTRUCTION_LENGTH);
   }