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
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} // namespace
47
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                        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
71bool 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
89bool 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?
95bool probeRequiredCPUFeatures() XRAY_NEVER_INSTRUMENT { return true; }
96
97bool 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
103bool 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
111extern "C" void __xray_ArgLoggerEntry() XRAY_NEVER_INSTRUMENT {
112  // FIXME: this will have to be implemented in the trampoline assembly file
113}
114