1 //===- Sanitizers.h - C Language Family Language Options --------*- 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 /// \file
10 /// Defines the clang::SanitizerKind enum.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #ifndef LLVM_CLANG_BASIC_SANITIZERS_H
15 #define LLVM_CLANG_BASIC_SANITIZERS_H
16
17 #include "clang/Basic/LLVM.h"
18 #include "llvm/ADT/StringRef.h"
19 #include "llvm/Transforms/Instrumentation/AddressSanitizerOptions.h"
20 #include <cassert>
21 #include <cstdint>
22
23 namespace llvm {
24 class hash_code;
25 }
26
27 namespace clang {
28
29 class SanitizerMask {
30 // NOTE: this class assumes kNumElem == 2 in most of the constexpr functions,
31 // in order to work within the C++11 constexpr function constraints. If you
32 // change kNumElem, you'll need to update those member functions as well.
33
34 /// Number of array elements.
35 static constexpr unsigned kNumElem = 2;
36 /// Mask value initialized to 0.
37 uint64_t maskLoToHigh[kNumElem]{};
38 /// Number of bits in a mask.
39 static constexpr unsigned kNumBits = sizeof(decltype(maskLoToHigh)) * 8;
40 /// Number of bits in a mask element.
41 static constexpr unsigned kNumBitElem = sizeof(decltype(maskLoToHigh[0])) * 8;
42
SanitizerMask(uint64_t mask1,uint64_t mask2)43 constexpr SanitizerMask(uint64_t mask1, uint64_t mask2)
44 : maskLoToHigh{mask1, mask2} {}
45
46 public:
47 SanitizerMask() = default;
48
checkBitPos(const unsigned Pos)49 static constexpr bool checkBitPos(const unsigned Pos) {
50 return Pos < kNumBits;
51 }
52
53 /// Create a mask with a bit enabled at position Pos.
bitPosToMask(const unsigned Pos)54 static constexpr SanitizerMask bitPosToMask(const unsigned Pos) {
55 uint64_t mask1 = (Pos < kNumBitElem) ? 1ULL << (Pos % kNumBitElem) : 0;
56 uint64_t mask2 = (Pos >= kNumBitElem && Pos < (kNumBitElem * 2))
57 ? 1ULL << (Pos % kNumBitElem)
58 : 0;
59 return SanitizerMask(mask1, mask2);
60 }
61
62 unsigned countPopulation() const;
63
flipAllBits()64 void flipAllBits() {
65 for (auto &Val : maskLoToHigh)
66 Val = ~Val;
67 }
68
isPowerOf2()69 bool isPowerOf2() const {
70 return countPopulation() == 1;
71 }
72
73 llvm::hash_code hash_value() const;
74
75 constexpr explicit operator bool() const {
76 return maskLoToHigh[0] || maskLoToHigh[1];
77 }
78
79 constexpr bool operator==(const SanitizerMask &V) const {
80 return maskLoToHigh[0] == V.maskLoToHigh[0] &&
81 maskLoToHigh[1] == V.maskLoToHigh[1];
82 }
83
84 SanitizerMask &operator&=(const SanitizerMask &RHS) {
85 for (unsigned k = 0; k < kNumElem; k++)
86 maskLoToHigh[k] &= RHS.maskLoToHigh[k];
87 return *this;
88 }
89
90 SanitizerMask &operator|=(const SanitizerMask &RHS) {
91 for (unsigned k = 0; k < kNumElem; k++)
92 maskLoToHigh[k] |= RHS.maskLoToHigh[k];
93 return *this;
94 }
95
96 constexpr bool operator!() const { return !bool(*this); }
97
98 constexpr bool operator!=(const SanitizerMask &RHS) const {
99 return !((*this) == RHS);
100 }
101
102 friend constexpr inline SanitizerMask operator~(SanitizerMask v) {
103 return SanitizerMask(~v.maskLoToHigh[0], ~v.maskLoToHigh[1]);
104 }
105
106 friend constexpr inline SanitizerMask operator&(SanitizerMask a,
107 const SanitizerMask &b) {
108 return SanitizerMask(a.maskLoToHigh[0] & b.maskLoToHigh[0],
109 a.maskLoToHigh[1] & b.maskLoToHigh[1]);
110 }
111
112 friend constexpr inline SanitizerMask operator|(SanitizerMask a,
113 const SanitizerMask &b) {
114 return SanitizerMask(a.maskLoToHigh[0] | b.maskLoToHigh[0],
115 a.maskLoToHigh[1] | b.maskLoToHigh[1]);
116 }
117 };
118
119 // Declaring in clang namespace so that it can be found by ADL.
120 llvm::hash_code hash_value(const clang::SanitizerMask &Arg);
121
122 // Define the set of sanitizer kinds, as well as the set of sanitizers each
123 // sanitizer group expands into.
124 struct SanitizerKind {
125 // Assign ordinals to possible values of -fsanitize= flag, which we will use
126 // as bit positions.
127 enum SanitizerOrdinal : uint64_t {
128 #define SANITIZER(NAME, ID) SO_##ID,
129 #define SANITIZER_GROUP(NAME, ID, ALIAS) SO_##ID##Group,
130 #include "clang/Basic/Sanitizers.def"
131 SO_Count
132 };
133
134 #define SANITIZER(NAME, ID) \
135 static constexpr SanitizerMask ID = SanitizerMask::bitPosToMask(SO_##ID); \
136 static_assert(SanitizerMask::checkBitPos(SO_##ID), "Bit position too big.");
137 #define SANITIZER_GROUP(NAME, ID, ALIAS) \
138 static constexpr SanitizerMask ID = SanitizerMask(ALIAS); \
139 static constexpr SanitizerMask ID##Group = \
140 SanitizerMask::bitPosToMask(SO_##ID##Group); \
141 static_assert(SanitizerMask::checkBitPos(SO_##ID##Group), \
142 "Bit position too big.");
143 #include "clang/Basic/Sanitizers.def"
144 }; // SanitizerKind
145
146 struct SanitizerSet {
147 /// Check if a certain (single) sanitizer is enabled.
hasSanitizerSet148 bool has(SanitizerMask K) const {
149 assert(K.isPowerOf2() && "Has to be a single sanitizer.");
150 return static_cast<bool>(Mask & K);
151 }
152
153 /// Check if one or more sanitizers are enabled.
hasOneOfSanitizerSet154 bool hasOneOf(SanitizerMask K) const { return static_cast<bool>(Mask & K); }
155
156 /// Enable or disable a certain (single) sanitizer.
setSanitizerSet157 void set(SanitizerMask K, bool Value) {
158 assert(K.isPowerOf2() && "Has to be a single sanitizer.");
159 Mask = Value ? (Mask | K) : (Mask & ~K);
160 }
161
162 /// Disable the sanitizers specified in \p K.
163 void clear(SanitizerMask K = SanitizerKind::All) { Mask &= ~K; }
164
165 /// Returns true if no sanitizers are enabled.
emptySanitizerSet166 bool empty() const { return !Mask; }
167
168 /// Bitmask of enabled sanitizers.
169 SanitizerMask Mask;
170 };
171
172 /// Parse a single value from a -fsanitize= or -fno-sanitize= value list.
173 /// Returns a non-zero SanitizerMask, or \c 0 if \p Value is not known.
174 SanitizerMask parseSanitizerValue(StringRef Value, bool AllowGroups);
175
176 /// Serialize a SanitizerSet into values for -fsanitize= or -fno-sanitize=.
177 void serializeSanitizerSet(SanitizerSet Set,
178 SmallVectorImpl<StringRef> &Values);
179
180 /// For each sanitizer group bit set in \p Kinds, set the bits for sanitizers
181 /// this group enables.
182 SanitizerMask expandSanitizerGroups(SanitizerMask Kinds);
183
184 /// Return the sanitizers which do not affect preprocessing.
getPPTransparentSanitizers()185 inline SanitizerMask getPPTransparentSanitizers() {
186 return SanitizerKind::CFI | SanitizerKind::Integer |
187 SanitizerKind::ImplicitConversion | SanitizerKind::Nullability |
188 SanitizerKind::Undefined | SanitizerKind::FloatDivideByZero;
189 }
190
191 StringRef AsanDtorKindToString(llvm::AsanDtorKind kind);
192
193 llvm::AsanDtorKind AsanDtorKindFromString(StringRef kind);
194
195 StringRef AsanDetectStackUseAfterReturnModeToString(
196 llvm::AsanDetectStackUseAfterReturnMode mode);
197
198 llvm::AsanDetectStackUseAfterReturnMode
199 AsanDetectStackUseAfterReturnModeFromString(StringRef modeStr);
200
201 } // namespace clang
202
203 #endif // LLVM_CLANG_BASIC_SANITIZERS_H
204