1 | //===-- xray_interface_internal.h -------------------------------*- 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 the API functions. See also include/xray/xray_interface.h. |
12 | // |
13 | //===----------------------------------------------------------------------===// |
14 | #ifndef XRAY_INTERFACE_INTERNAL_H |
15 | #define XRAY_INTERFACE_INTERNAL_H |
16 | |
17 | #include "sanitizer_common/sanitizer_platform.h" |
18 | #include "xray/xray_interface.h" |
19 | #include <cstddef> |
20 | #include <cstdint> |
21 | #include <utility> |
22 | |
23 | extern "C" { |
24 | // The following functions have to be defined in assembler, on a per-platform |
25 | // basis. See xray_trampoline_*.S files for implementations. |
26 | extern void __xray_FunctionEntry(); |
27 | extern void __xray_FunctionExit(); |
28 | extern void __xray_FunctionTailExit(); |
29 | extern void __xray_ArgLoggerEntry(); |
30 | extern void __xray_CustomEvent(); |
31 | extern void __xray_TypedEvent(); |
32 | #if defined(__s390x__) |
33 | extern void __xray_FunctionEntryVec(); |
34 | extern void __xray_FunctionExitVec(); |
35 | #endif |
36 | } |
37 | |
38 | extern "C" { |
39 | |
40 | struct XRaySledEntry { |
41 | #if SANITIZER_WORDSIZE == 64 |
42 | uint64_t Address; |
43 | uint64_t Function; |
44 | unsigned char Kind; |
45 | unsigned char AlwaysInstrument; |
46 | unsigned char Version; |
47 | unsigned char Padding[13]; // Need 32 bytes |
48 | uint64_t function() const { |
49 | // The target address is relative to the location of the Function variable. |
50 | return reinterpret_cast<uint64_t>(&Function) + Function; |
51 | } |
52 | uint64_t address() const { |
53 | // The target address is relative to the location of the Address variable. |
54 | return reinterpret_cast<uint64_t>(&Address) + Address; |
55 | } |
56 | #elif SANITIZER_WORDSIZE == 32 |
57 | uint32_t Address; |
58 | uint32_t Function; |
59 | unsigned char Kind; |
60 | unsigned char AlwaysInstrument; |
61 | unsigned char Version; |
62 | unsigned char Padding[5]; // Need 16 bytes |
63 | uint32_t function() const { |
64 | // The target address is relative to the location of the Function variable. |
65 | return reinterpret_cast<uint32_t>(&Function) + Function; |
66 | } |
67 | uint32_t address() const { |
68 | // The target address is relative to the location of the Address variable. |
69 | return reinterpret_cast<uint32_t>(&Address) + Address; |
70 | } |
71 | #else |
72 | #error "Unsupported word size." |
73 | #endif |
74 | }; |
75 | |
76 | struct XRayFunctionSledIndex { |
77 | const XRaySledEntry *Begin; |
78 | size_t Size; |
79 | // For an entry in the xray_fn_idx section, the address is relative to the |
80 | // location of the Begin variable. |
81 | const XRaySledEntry *fromPCRelative() const { |
82 | return reinterpret_cast<const XRaySledEntry *>(uintptr_t(&Begin) + |
83 | uintptr_t(Begin)); |
84 | } |
85 | }; |
86 | |
87 | struct XRayTrampolines { |
88 | void (*EntryTrampoline)(); |
89 | void (*ExitTrampoline)(); |
90 | void (*TailExitTrampoline)(); |
91 | void (*LogArgsTrampoline)(); |
92 | |
93 | XRayTrampolines() { |
94 | // These resolve to the definitions in the respective executable or DSO. |
95 | EntryTrampoline = __xray_FunctionEntry; |
96 | ExitTrampoline = __xray_FunctionExit; |
97 | TailExitTrampoline = __xray_FunctionTailExit; |
98 | LogArgsTrampoline = __xray_ArgLoggerEntry; |
99 | } |
100 | }; |
101 | |
102 | extern int32_t __xray_register_dso(const XRaySledEntry *SledsBegin, |
103 | const XRaySledEntry *SledsEnd, |
104 | const XRayFunctionSledIndex *FnIndexBegin, |
105 | const XRayFunctionSledIndex *FnIndexEnd, |
106 | XRayTrampolines Trampolines); |
107 | |
108 | extern bool __xray_deregister_dso(int32_t ObjId); |
109 | } |
110 | |
111 | namespace __xray { |
112 | |
113 | constexpr uint32_t XRayNFnBits = 24; |
114 | constexpr uint32_t XRayNObjBits = 8; |
115 | |
116 | constexpr uint32_t XRayFnBitMask = 0x00FFFFFF; |
117 | constexpr uint32_t XRayObjBitMask = 0xFF000000; |
118 | |
119 | constexpr size_t XRayMaxFunctions = 1 << XRayNFnBits; |
120 | constexpr size_t XRayMaxObjects = 1 << XRayNObjBits; |
121 | |
122 | inline int32_t MakePackedId(int32_t FnId, int32_t ObjId) { |
123 | return ((ObjId << XRayNFnBits) & XRayObjBitMask) | (FnId & XRayFnBitMask); |
124 | } |
125 | |
126 | inline std::pair<int32_t, int32_t> UnpackId(int32_t PackedId) { |
127 | uint32_t ObjId = (PackedId & XRayObjBitMask) >> XRayNFnBits; |
128 | uint32_t FnId = PackedId & XRayFnBitMask; |
129 | return {ObjId, FnId}; |
130 | } |
131 | |
132 | struct XRaySledMap { |
133 | const XRaySledEntry *Sleds; |
134 | size_t Entries; |
135 | const XRayFunctionSledIndex *SledsIndex; |
136 | size_t Functions; |
137 | XRayTrampolines Trampolines; |
138 | bool FromDSO; |
139 | bool Loaded; |
140 | }; |
141 | |
142 | bool patchFunctionEntry(bool Enable, uint32_t FuncId, const XRaySledEntry &Sled, |
143 | const XRayTrampolines &Trampolines, bool LogArgs); |
144 | bool patchFunctionExit(bool Enable, uint32_t FuncId, const XRaySledEntry &Sled, |
145 | const XRayTrampolines &Trampolines); |
146 | bool patchFunctionTailExit(bool Enable, uint32_t FuncId, |
147 | const XRaySledEntry &Sled, |
148 | const XRayTrampolines &Trampolines); |
149 | bool patchCustomEvent(bool Enable, uint32_t FuncId, const XRaySledEntry &Sled); |
150 | bool patchTypedEvent(bool Enable, uint32_t FuncId, const XRaySledEntry &Sled); |
151 | |
152 | } // namespace __xray |
153 | |
154 | #endif |
155 | |