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//===-- Flags.h -------------------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef LLDB_UTILITY_FLAGS_H
#define LLDB_UTILITY_FLAGS_H
#include <cstddef>
#include <cstdint>
namespace lldb_private {
//----------------------------------------------------------------------
/// @class Flags Flags.h "lldb/Utility/Flags.h"
/// A class to manage flags.
///
/// The Flags class managed flag bits and allows testing and modification of
/// individual or multiple flag bits.
//----------------------------------------------------------------------
class Flags {
public:
//----------------------------------------------------------------------
/// The value type for flags is a 32 bit unsigned integer type.
//----------------------------------------------------------------------
typedef uint32_t ValueType;
//----------------------------------------------------------------------
/// Construct with initial flag bit values.
///
/// Constructs this object with \a mask as the initial value for all of the
/// flags.
///
/// @param[in] mask
/// The initial value for all flags.
//----------------------------------------------------------------------
Flags(ValueType flags = 0) : m_flags(flags) {}
//----------------------------------------------------------------------
/// Copy constructor.
///
/// Construct and copy the flags from \a rhs.
///
/// @param[in] rhs
/// A const Flags object reference to copy.
//----------------------------------------------------------------------
Flags(const Flags &rhs) : m_flags(rhs.m_flags) {}
//----------------------------------------------------------------------
/// Destructor.
//----------------------------------------------------------------------
~Flags() {}
//----------------------------------------------------------------------
/// Get accessor for all flags.
///
/// @return
/// Returns all of the flags as a Flags::ValueType.
//----------------------------------------------------------------------
ValueType Get() const { return m_flags; }
//----------------------------------------------------------------------
/// Return the number of flags that can be represented in this object.
///
/// @return
/// The maximum number bits in this flag object.
//----------------------------------------------------------------------
size_t GetBitSize() const { return sizeof(ValueType) * 8; }
//----------------------------------------------------------------------
/// Set accessor for all flags.
///
/// @param[in] flags
/// The bits with which to replace all of the current flags.
//----------------------------------------------------------------------
void Reset(ValueType flags) { m_flags = flags; }
//----------------------------------------------------------------------
/// Clear one or more flags.
///
/// @param[in] mask
/// A bitfield containing one or more flags.
///
/// @return
/// The new flags after clearing all bits from \a mask.
//----------------------------------------------------------------------
ValueType Clear(ValueType mask = ~(ValueType)0) {
m_flags &= ~mask;
return m_flags;
}
//----------------------------------------------------------------------
/// Set one or more flags by logical OR'ing \a mask with the current flags.
///
/// @param[in] mask
/// A bitfield containing one or more flags.
///
/// @return
/// The new flags after setting all bits from \a mask.
//----------------------------------------------------------------------
ValueType Set(ValueType mask) {
m_flags |= mask;
return m_flags;
}
//----------------------------------------------------------------------
/// Test if all bits in \a mask are 1 in the current flags
///
/// @return
/// \b true if all flags in \a mask are 1, \b false
/// otherwise.
//----------------------------------------------------------------------
bool AllSet(ValueType mask) const { return (m_flags & mask) == mask; }
//----------------------------------------------------------------------
/// Test one or more flags.
///
/// @return
/// \b true if any flags in \a mask are 1, \b false
/// otherwise.
//----------------------------------------------------------------------
bool AnySet(ValueType mask) const { return (m_flags & mask) != 0; }
//----------------------------------------------------------------------
/// Test a single flag bit.
///
/// @return
/// \b true if \a bit is set, \b false otherwise.
//----------------------------------------------------------------------
bool Test(ValueType bit) const { return (m_flags & bit) != 0; }
//----------------------------------------------------------------------
/// Test if all bits in \a mask are clear.
///
/// @return
/// \b true if \b all flags in \a mask are clear, \b false
/// otherwise.
//----------------------------------------------------------------------
bool AllClear(ValueType mask) const { return (m_flags & mask) == 0; }
bool AnyClear(ValueType mask) const { return (m_flags & mask) != mask; }
//----------------------------------------------------------------------
/// Test a single flag bit to see if it is clear (zero).
///
/// @return
/// \b true if \a bit is 0, \b false otherwise.
//----------------------------------------------------------------------
bool IsClear(ValueType bit) const { return (m_flags & bit) == 0; }
//----------------------------------------------------------------------
/// Get the number of zero bits in \a m_flags.
///
/// @return
/// The number of bits that are set to 0 in the current flags.
//----------------------------------------------------------------------
size_t ClearCount() const {
size_t count = 0;
for (ValueType shift = 0; shift < sizeof(ValueType) * 8; ++shift) {
if ((m_flags & (1u << shift)) == 0)
++count;
}
return count;
}
//----------------------------------------------------------------------
/// Get the number of one bits in \a m_flags.
///
/// @return
/// The number of bits that are set to 1 in the current flags.
//----------------------------------------------------------------------
size_t SetCount() const {
size_t count = 0;
for (ValueType mask = m_flags; mask; mask >>= 1) {
if (mask & 1u)
++count;
}
return count;
}
protected:
ValueType m_flags; ///< The flags.
};
} // namespace lldb_private
#endif // liblldb_Flags_h_