clang 10.0.0git

APSIntType.h
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1 //== APSIntType.h - Simple record of the type of APSInts --------*- 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 #ifndef LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_APSINTTYPE_H
10 #define LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_APSINTTYPE_H
11
12 #include "llvm/ADT/APSInt.h"
13 #include <tuple>
14
15 namespace clang {
16 namespace ento {
17
18 /// A record of the "type" of an APSInt, used for conversions.
19 class APSIntType {
20 uint32_t BitWidth;
21 bool IsUnsigned;
22
23 public:
24 APSIntType(uint32_t Width, bool Unsigned)
25 : BitWidth(Width), IsUnsigned(Unsigned) {}
26
27 /* implicit */ APSIntType(const llvm::APSInt &Value)
28 : BitWidth(Value.getBitWidth()), IsUnsigned(Value.isUnsigned()) {}
29
30 uint32_t getBitWidth() const { return BitWidth; }
31 bool isUnsigned() const { return IsUnsigned; }
32
33 /// Convert a given APSInt, in place, to match this type.
34 ///
35 /// This behaves like a C cast: converting 255u8 (0xFF) to s16 gives
36 /// 255 (0x00FF), and converting -1s8 (0xFF) to u16 gives 65535 (0xFFFF).
37 void apply(llvm::APSInt &Value) const {
38 // Note the order here. We extend first to preserve the sign, if this value
39 // is signed, /then/ match the signedness of the result type.
40 Value = Value.extOrTrunc(BitWidth);
41 Value.setIsUnsigned(IsUnsigned);
42 }
43
44 /// Convert and return a new APSInt with the given value, but this
45 /// type's bit width and signedness.
46 ///
47 /// \see apply
48 llvm::APSInt convert(const llvm::APSInt &Value) const LLVM_READONLY {
49 llvm::APSInt Result(Value, Value.isUnsigned());
50 apply(Result);
51 return Result;
52 }
53
54 /// Returns an all-zero value for this type.
55 llvm::APSInt getZeroValue() const LLVM_READONLY {
56 return llvm::APSInt(BitWidth, IsUnsigned);
57 }
58
59 /// Returns the minimum value for this type.
60 llvm::APSInt getMinValue() const LLVM_READONLY {
61 return llvm::APSInt::getMinValue(BitWidth, IsUnsigned);
62 }
63
64 /// Returns the maximum value for this type.
65 llvm::APSInt getMaxValue() const LLVM_READONLY {
66 return llvm::APSInt::getMaxValue(BitWidth, IsUnsigned);
67 }
68
69 llvm::APSInt getValue(uint64_t RawValue) const LLVM_READONLY {
70 return (llvm::APSInt(BitWidth, IsUnsigned) = RawValue);
71 }
72
73 /// Used to classify whether a value is representable using this type.
74 ///
75 /// \see testInRange
76 enum RangeTestResultKind {
77 RTR_Below = -1, ///< Value is less than the minimum representable value.
78 RTR_Within = 0, ///< Value is representable using this type.
79 RTR_Above = 1 ///< Value is greater than the maximum representable value.
80 };
81
82 /// Tests whether a given value is losslessly representable using this type.
83 ///
84 /// \param Val The value to test.
85 /// \param AllowMixedSign Whether or not to allow signedness conversions.
86 /// This determines whether -1s8 is considered in range
87 /// for 'unsigned char' (u8).
88 RangeTestResultKind testInRange(const llvm::APSInt &Val,
89 bool AllowMixedSign) const LLVM_READONLY;
90
91 bool operator==(const APSIntType &Other) const {
92 return BitWidth == Other.BitWidth && IsUnsigned == Other.IsUnsigned;
93 }
94
95 /// Provide an ordering for finding a common conversion type.
96 ///
97 /// Unsigned integers are considered to be better conversion types than
98 /// signed integers of the same width.
99 bool operator<(const APSIntType &Other) const {
100 return std::tie(BitWidth, IsUnsigned) <
101 std::tie(Other.BitWidth, Other.IsUnsigned);
102 }
103 };
104
105 } // end ento namespace
106 } // end clang namespace
107
108 #endif
ento
clang::ento::APSIntType::operator==
bool operator==(const APSIntType &Other) const
Definition: APSIntType.h:91
clang::ento::APSIntType::RTR_Below
Value is less than the minimum representable value.
Definition: APSIntType.h:77
Value
Value
Definition: UninitializedValues.cpp:101
clang::ento::APSIntType::APSIntType
APSIntType(const llvm::APSInt &Value)
Definition: APSIntType.h:27
clang::ento::APSIntType::RTR_Within
Value is representable using this type.
Definition: APSIntType.h:78
clang::ento::APSIntType
A record of the "type" of an APSInt, used for conversions.
Definition: APSIntType.h:19
clang::ento::APSIntType::APSIntType
APSIntType(uint32_t Width, bool Unsigned)
Definition: APSIntType.h:24
clang::ento::APSIntType::testInRange
RangeTestResultKind testInRange(const llvm::APSInt &Val, bool AllowMixedSign) const LLVM_READONLY
Tests whether a given value is losslessly representable using this type.
Definition: APSIntType.cpp:15
clang::ento::APSIntType::getZeroValue
llvm::APSInt getZeroValue() const LLVM_READONLY
Returns an all-zero value for this type.
Definition: APSIntType.h:55
clang::ento::APSIntType::getMinValue
llvm::APSInt getMinValue() const LLVM_READONLY
Returns the minimum value for this type.
Definition: APSIntType.h:60
clang::ento::APSIntType::getBitWidth
uint32_t getBitWidth() const
Definition: APSIntType.h:30
clang::ento::APSIntType::getMaxValue
llvm::APSInt getMaxValue() const LLVM_READONLY
Returns the maximum value for this type.
Definition: APSIntType.h:65
APSInt
llvm::APSInt APSInt
Definition: ByteCodeEmitter.cpp:18
clang::ento::APSIntType::operator<
bool operator<(const APSIntType &Other) const
Provide an ordering for finding a common conversion type.
Definition: APSIntType.h:99
clang::ento::APSIntType::RTR_Above
Value is greater than the maximum representable value.
Definition: APSIntType.h:79
clang::ento::APSIntType::RangeTestResultKind
RangeTestResultKind
Used to classify whether a value is representable using this type.
Definition: APSIntType.h:76
clang::ento::APSIntType::getValue
llvm::APSInt getValue(uint64_t RawValue) const LLVM_READONLY
Definition: APSIntType.h:69
clang::ento::APSIntType::convert
llvm::APSInt convert(const llvm::APSInt &Value) const LLVM_READONLY
Convert and return a new APSInt with the given value, but this type&#39;s bit width and signedness...
Definition: APSIntType.h:48
clang
Dataflow Directional Tag Classes.
Definition: CFGReachabilityAnalysis.h:21
clang::ento::APSIntType::isUnsigned
bool isUnsigned() const
Definition: APSIntType.h:31
clang::ento::APSIntType::apply
void apply(llvm::APSInt &Value) const
Convert a given APSInt, in place, to match this type.
Definition: APSIntType.h:37