compiler-rt/lib/xray/xray_powerpc64.cpp

   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-exception
   6 //
   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 #endif
  25
  26 namespace {
  27
  28 constexpr unsigned long long JumpOverInstNum = 7;
  29
  30 void 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 } // namespace
  47
  48 extern "C" void __clear_cache(void *start, void *end);
  49
  50 namespace __xray {
  51
  52 bool patchFunctionEntry(const bool Enable, uint32_t FuncId,
  53                         const XRaySledEntry &Sled,
  54                         void (*Trampoline)()) XRAY_NEVER_INSTRUMENT {
  55   const uint64_t Address = Sled.address();
  56   if (Enable) {
  57     // lis 0, FuncId[16..32]
  58     // li 0, FuncId[0..15]
  59     *reinterpret_cast<uint64_t *>(Address) =
  60         (0x3c000000ull + (FuncId >> 16)) +
  61         ((0x60000000ull + (FuncId & 0xffff)) << 32);
  62   } else {
  63     // b +JumpOverInstNum instructions.
  64     *reinterpret_cast<uint32_t *>(Address) =
  65         0x48000000ull + (JumpOverInstNum << 2);
  66   }
  67   clearCache(reinterpret_cast<void *>(Address), 8);
  68   return true;
  69 }
  70
  71 bool patchFunctionExit(const bool Enable, uint32_t FuncId,
  72                        const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT {
  73   const uint64_t Address = Sled.address();
  74   if (Enable) {
  75     // lis 0, FuncId[16..32]
  76     // li 0, FuncId[0..15]
  77     *reinterpret_cast<uint64_t *>(Address) =
  78         (0x3c000000ull + (FuncId >> 16)) +
  79         ((0x60000000ull + (FuncId & 0xffff)) << 32);
  80   } else {
  81     // Copy the blr/b instruction after JumpOverInstNum instructions.
  82     *reinterpret_cast<uint32_t *>(Address) =
  83         *(reinterpret_cast<uint32_t *>(Address) + JumpOverInstNum);
  84   }
  85   clearCache(reinterpret_cast<void *>(Address), 8);
  86   return true;
  87 }
  88
  89 bool patchFunctionTailExit(const bool Enable, const uint32_t FuncId,
  90                            const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT {
  91   return patchFunctionExit(Enable, FuncId, Sled);
  92 }
  93
  94 // FIXME: Maybe implement this better?
  95 bool probeRequiredCPUFeatures() XRAY_NEVER_INSTRUMENT { return true; }
  96
  97 bool patchCustomEvent(const bool Enable, const uint32_t FuncId,
  98                       const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT {
  99   // FIXME: Implement in powerpc64?
 100   return false;
 101 }
 102
 103 bool patchTypedEvent(const bool Enable, const uint32_t FuncId,
 104                      const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT {
 105   // FIXME: Implement in powerpc64?
 106   return false;
 107 }
 108
 109 } // namespace __xray
 110
 111 extern "C" void __xray_ArgLoggerEntry() XRAY_NEVER_INSTRUMENT {
 112   // FIXME: this will have to be implemented in the trampoline assembly file
 113 }