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//===- MCSymbolMachO.h - ---------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_MC_MCSYMBOLMACHO_H
#define LLVM_MC_MCSYMBOLMACHO_H
#include "llvm/ADT/Twine.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/MC/MCSymbolTableEntry.h"
namespace llvm {
class MCSymbolMachO : public MCSymbol {
/// We store the value for the 'desc' symbol field in the
/// lowest 16 bits of the implementation defined flags.
enum MachOSymbolFlags : uint16_t { // See <mach-o/nlist.h>.
SF_DescFlagsMask = 0xFFFF,
// Reference type flags.
SF_ReferenceTypeMask = 0x0007,
SF_ReferenceTypeUndefinedNonLazy = 0x0000,
SF_ReferenceTypeUndefinedLazy = 0x0001,
SF_ReferenceTypeDefined = 0x0002,
SF_ReferenceTypePrivateDefined = 0x0003,
SF_ReferenceTypePrivateUndefinedNonLazy = 0x0004,
SF_ReferenceTypePrivateUndefinedLazy = 0x0005,
// Other 'desc' flags.
SF_ThumbFunc = 0x0008,
SF_NoDeadStrip = 0x0020,
SF_WeakReference = 0x0040,
SF_WeakDefinition = 0x0080,
SF_SymbolResolver = 0x0100,
SF_AltEntry = 0x0200,
SF_Cold = 0x0400,
// Common alignment
SF_CommonAlignmentMask = 0xF0FF,
SF_CommonAlignmentShift = 8
};
public:
MCSymbolMachO(const MCSymbolTableEntry *Name, bool isTemporary)
: MCSymbol(SymbolKindMachO, Name, isTemporary) {}
bool isPrivateExtern() const { return IsPrivateExtern; }
void setPrivateExtern(bool Value) { IsPrivateExtern = Value; }
// Reference type methods.
void clearReferenceType() const {
modifyFlags(0, SF_ReferenceTypeMask);
}
void setReferenceTypeUndefinedLazy(bool Value) const {
modifyFlags(Value ? SF_ReferenceTypeUndefinedLazy : 0,
SF_ReferenceTypeUndefinedLazy);
}
// Other 'desc' methods.
void setThumbFunc() const {
modifyFlags(SF_ThumbFunc, SF_ThumbFunc);
}
bool isNoDeadStrip() const {
return getFlags() & SF_NoDeadStrip;
}
void setNoDeadStrip() const {
modifyFlags(SF_NoDeadStrip, SF_NoDeadStrip);
}
bool isWeakReference() const {
return getFlags() & SF_WeakReference;
}
void setWeakReference() const {
modifyFlags(SF_WeakReference, SF_WeakReference);
}
bool isWeakDefinition() const {
return getFlags() & SF_WeakDefinition;
}
void setWeakDefinition() const {
modifyFlags(SF_WeakDefinition, SF_WeakDefinition);
}
bool isSymbolResolver() const {
return getFlags() & SF_SymbolResolver;
}
void setSymbolResolver() const {
modifyFlags(SF_SymbolResolver, SF_SymbolResolver);
}
void setAltEntry() const {
modifyFlags(SF_AltEntry, SF_AltEntry);
}
bool isAltEntry() const {
return getFlags() & SF_AltEntry;
}
void setCold() const { modifyFlags(SF_Cold, SF_Cold); }
bool isCold() const { return getFlags() & SF_Cold; }
void setDesc(unsigned Value) const {
assert(Value == (Value & SF_DescFlagsMask) &&
"Invalid .desc value!");
setFlags(Value & SF_DescFlagsMask);
}
// Check whether a particular symbol is visible to the linker and is required
// in the symbol table, or whether it can be discarded by the assembler. This
// also effects whether the assembler treats the label as potentially defining
// a separate atom.
bool isSymbolLinkerVisible() const {
// Non-temporary labels should always be visible to the linker.
if (!isTemporary())
return true;
return isUsedInReloc();
}
/// Get the encoded value of the flags as they will be emitted in to
/// the MachO binary
uint16_t getEncodedFlags(bool EncodeAsAltEntry) const {
uint16_t Flags = getFlags();
// Common alignment is packed into the 'desc' bits.
if (isCommon()) {
if (MaybeAlign MaybeAlignment = getCommonAlignment()) {
Align Alignment = *MaybeAlignment;
unsigned Log2Size = Log2(Alignment);
if (Log2Size > 15)
report_fatal_error("invalid 'common' alignment '" +
Twine(Alignment.value()) + "' for '" +
getName() + "'",
false);
Flags = (Flags & SF_CommonAlignmentMask) |
(Log2Size << SF_CommonAlignmentShift);
}
}
if (EncodeAsAltEntry)
Flags |= SF_AltEntry;
return Flags;
}
static bool classof(const MCSymbol *S) { return S->isMachO(); }
};
}
#endif
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