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1//===-- xray_powerpc64.cpp --------------------------------------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file is a part of XRay, a dynamic runtime instrumentation system.10//11// Implementation of powerpc64 and powerpc64le routines.12//13//===----------------------------------------------------------------------===//14#include "sanitizer_common/sanitizer_common.h"15#include "xray_defs.h"16#include "xray_interface_internal.h"17#include "xray_utils.h"18#include <atomic>19#include <cassert>20#include <cstring>21 22#ifndef __LITTLE_ENDIAN__23#error powerpc64 big endian is not supported for now.24#endif25 26namespace {27 28constexpr unsigned long long JumpOverInstNum = 7;29 30void clearCache(void *Addr, size_t Len) {31  const size_t LineSize = 32;32 33  const intptr_t Mask = ~(LineSize - 1);34  const intptr_t StartLine = ((intptr_t)Addr) & Mask;35  const intptr_t EndLine = ((intptr_t)Addr + Len + LineSize - 1) & Mask;36 37  for (intptr_t Line = StartLine; Line < EndLine; Line += LineSize)38    asm volatile("dcbf 0, %0" : : "r"(Line));39  asm volatile("sync");40 41  for (intptr_t Line = StartLine; Line < EndLine; Line += LineSize)42    asm volatile("icbi 0, %0" : : "r"(Line));43  asm volatile("isync");44}45 46} // namespace47 48extern "C" void __clear_cache(void *start, void *end);49 50namespace __xray {51 52bool patchFunctionEntry(const bool Enable, uint32_t FuncId,53                        const XRaySledEntry &Sled,54                        const XRayTrampolines &Trampolines,55                        bool LogArgs) XRAY_NEVER_INSTRUMENT {56  // TODO: Trampoline addresses are currently inserted at compile-time, using57  //       __xray_FunctionEntry and __xray_FunctionExit only.58  //       To support DSO instrumentation, trampolines have to be written during59  //       patching (see implementation on X86_64, e.g.).60  const uint64_t Address = Sled.address();61  if (Enable) {62    // lis 0, FuncId[16..32]63    // li 0, FuncId[0..15]64    *reinterpret_cast<uint64_t *>(Address) =65        (0x3c000000ull + (FuncId >> 16)) +66        ((0x60000000ull + (FuncId & 0xffff)) << 32);67  } else {68    // b +JumpOverInstNum instructions.69    *reinterpret_cast<uint32_t *>(Address) =70        0x48000000ull + (JumpOverInstNum << 2);71  }72  clearCache(reinterpret_cast<void *>(Address), 8);73  return true;74}75 76bool patchFunctionExit(77    const bool Enable, uint32_t FuncId, const XRaySledEntry &Sled,78    const XRayTrampolines &Trampolines) XRAY_NEVER_INSTRUMENT {79  // TODO: Trampoline addresses are currently inserted at compile-time, using80  //       __xray_FunctionEntry and __xray_FunctionExit only.81  //       To support DSO instrumentation, trampolines have to be written during82  //       patching (see implementation on X86_64, e.g.).83  const uint64_t Address = Sled.address();84  if (Enable) {85    // lis 0, FuncId[16..32]86    // li 0, FuncId[0..15]87    *reinterpret_cast<uint64_t *>(Address) =88        (0x3c000000ull + (FuncId >> 16)) +89        ((0x60000000ull + (FuncId & 0xffff)) << 32);90  } else {91    // Copy the blr/b instruction after JumpOverInstNum instructions.92    *reinterpret_cast<uint32_t *>(Address) =93        *(reinterpret_cast<uint32_t *>(Address) + JumpOverInstNum);94  }95  clearCache(reinterpret_cast<void *>(Address), 8);96  return true;97}98 99bool patchFunctionTailExit(100    const bool Enable, const uint32_t FuncId, const XRaySledEntry &Sled,101    const XRayTrampolines &Trampolines) XRAY_NEVER_INSTRUMENT {102  return patchFunctionExit(Enable, FuncId, Sled, Trampolines);103}104 105// FIXME: Maybe implement this better?106bool probeRequiredCPUFeatures() XRAY_NEVER_INSTRUMENT { return true; }107 108bool patchCustomEvent(const bool Enable, const uint32_t FuncId,109                      const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT {110  // FIXME: Implement in powerpc64?111  return false;112}113 114bool patchTypedEvent(const bool Enable, const uint32_t FuncId,115                     const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT {116  // FIXME: Implement in powerpc64?117  return false;118}119 120} // namespace __xray121 122extern "C" void __xray_ArgLoggerEntry() XRAY_NEVER_INSTRUMENT {123  // FIXME: this will have to be implemented in the trampoline assembly file124}125 126extern "C" void __xray_FunctionTailExit() XRAY_NEVER_INSTRUMENT {127  // For PowerPC, calls to __xray_FunctionEntry and __xray_FunctionExit128  // are statically inserted into the sled. Tail exits are handled like normal129  // function exits. This trampoline is therefore not implemented.130  // This stub is placed here to avoid linking issues.131}132