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Flags.h
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1 //===-- Flags.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 #ifndef LLDB_UTILITY_FLAGS_H
10 #define LLDB_UTILITY_FLAGS_H
11 
12 #include <cstddef>
13 #include <cstdint>
14 
15 namespace lldb_private {
16 
17 /// \class Flags Flags.h "lldb/Utility/Flags.h"
18 /// A class to manage flags.
19 ///
20 /// The Flags class managed flag bits and allows testing and modification of
21 /// individual or multiple flag bits.
22 class Flags {
23 public:
24  /// The value type for flags is a 32 bit unsigned integer type.
26 
27  /// Construct with initial flag bit values.
28  ///
29  /// Constructs this object with \a mask as the initial value for all of the
30  /// flags.
31  ///
32  /// \param[in] flags
33  /// The initial value for all flags.
34  Flags(ValueType flags = 0) : m_flags(flags) {}
35 
36  /// Get accessor for all flags.
37  ///
38  /// \return
39  /// Returns all of the flags as a Flags::ValueType.
40  ValueType Get() const { return m_flags; }
41 
42  /// Return the number of flags that can be represented in this object.
43  ///
44  /// \return
45  /// The maximum number bits in this flag object.
46  size_t GetBitSize() const { return sizeof(ValueType) * 8; }
47 
48  /// Set accessor for all flags.
49  ///
50  /// \param[in] flags
51  /// The bits with which to replace all of the current flags.
52  void Reset(ValueType flags) { m_flags = flags; }
53 
54  /// Clear one or more flags.
55  ///
56  /// \param[in] mask
57  /// A bitfield containing one or more flags.
58  ///
59  /// \return
60  /// The new flags after clearing all bits from \a mask.
61  ValueType Clear(ValueType mask = ~static_cast<ValueType>(0)) {
62  m_flags &= ~mask;
63  return m_flags;
64  }
65 
66  /// Set one or more flags by logical OR'ing \a mask with the current flags.
67  ///
68  /// \param[in] mask
69  /// A bitfield containing one or more flags.
70  ///
71  /// \return
72  /// The new flags after setting all bits from \a mask.
74  m_flags |= mask;
75  return m_flags;
76  }
77 
78  /// Test if all bits in \a mask are 1 in the current flags
79  ///
80  /// \return
81  /// \b true if all flags in \a mask are 1, \b false
82  /// otherwise.
83  bool AllSet(ValueType mask) const { return (m_flags & mask) == mask; }
84 
85  /// Test one or more flags.
86  ///
87  /// \return
88  /// \b true if any flags in \a mask are 1, \b false
89  /// otherwise.
90  bool AnySet(ValueType mask) const { return (m_flags & mask) != 0; }
91 
92  /// Test a single flag bit.
93  ///
94  /// \return
95  /// \b true if \a bit is set, \b false otherwise.
96  bool Test(ValueType bit) const { return (m_flags & bit) != 0; }
97 
98  /// Test if all bits in \a mask are clear.
99  ///
100  /// \return
101  /// \b true if \b all flags in \a mask are clear, \b false
102  /// otherwise.
103  bool AllClear(ValueType mask) const { return (m_flags & mask) == 0; }
104 
105  bool AnyClear(ValueType mask) const { return (m_flags & mask) != mask; }
106 
107  /// Test a single flag bit to see if it is clear (zero).
108  ///
109  /// \return
110  /// \b true if \a bit is 0, \b false otherwise.
111  bool IsClear(ValueType bit) const { return (m_flags & bit) == 0; }
112 
113 protected:
114  ValueType m_flags; ///< The flags.
115 };
116 
117 } // namespace lldb_private
118 
119 #endif // LLDB_UTILITY_FLAGS_H
lldb_private::Flags::AnySet
bool AnySet(ValueType mask) const
Test one or more flags.
Definition: Flags.h:90
lldb_private::Flags::AllClear
bool AllClear(ValueType mask) const
Test if all bits in mask are clear.
Definition: Flags.h:103
lldb_private::Flags::Clear
ValueType Clear(ValueType mask=~static_cast< ValueType >(0))
Clear one or more flags.
Definition: Flags.h:61
lldb_private::Flags::ValueType
uint32_t ValueType
The value type for flags is a 32 bit unsigned integer type.
Definition: Flags.h:25
lldb_private::Flags
Definition: Flags.h:22
lldb_private::Flags::Test
bool Test(ValueType bit) const
Test a single flag bit.
Definition: Flags.h:96
lldb_private::Flags::AnyClear
bool AnyClear(ValueType mask) const
Definition: Flags.h:105
lldb_private::Flags::m_flags
ValueType m_flags
The flags.
Definition: Flags.h:114
lldb_private::Flags::AllSet
bool AllSet(ValueType mask) const
Test if all bits in mask are 1 in the current flags.
Definition: Flags.h:83
lldb_private::bit
static uint32_t bit(const uint32_t val, const uint32_t msbit)
Definition: ARMUtils.h:269
lldb_private::Flags::Reset
void Reset(ValueType flags)
Set accessor for all flags.
Definition: Flags.h:52
lldb_private::Flags::Flags
Flags(ValueType flags=0)
Construct with initial flag bit values.
Definition: Flags.h:34
uint32_t
lldb_private::Flags::Get
ValueType Get() const
Get accessor for all flags.
Definition: Flags.h:40
lldb_private
A class that represents a running process on the host machine.
Definition: SBCommandInterpreterRunOptions.h:16
lldb_private::Flags::Set
ValueType Set(ValueType mask)
Set one or more flags by logical OR'ing mask with the current flags.
Definition: Flags.h:73
lldb_private::Flags::GetBitSize
size_t GetBitSize() const
Return the number of flags that can be represented in this object.
Definition: Flags.h:46
lldb_private::Flags::IsClear
bool IsClear(ValueType bit) const
Test a single flag bit to see if it is clear (zero).
Definition: Flags.h:111