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| Rev | Author | Line No. | Line | 
|---|---|---|---|
| 14 | pmbaty | 1 | //===- MCSectionELF.h - ELF Machine Code Sections ---------------*- 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 | // This file declares the MCSectionELF class. | ||
| 10 | // | ||
| 11 | //===----------------------------------------------------------------------===// | ||
| 12 | |||
| 13 | #ifndef LLVM_MC_MCSECTIONELF_H | ||
| 14 | #define LLVM_MC_MCSECTIONELF_H | ||
| 15 | |||
| 16 | #include "llvm/ADT/PointerIntPair.h" | ||
| 17 | #include "llvm/ADT/StringRef.h" | ||
| 18 | #include "llvm/MC/MCSection.h" | ||
| 19 | #include "llvm/MC/MCSymbolELF.h" | ||
| 20 | #include "llvm/MC/SectionKind.h" | ||
| 21 | |||
| 22 | namespace llvm { | ||
| 23 | |||
| 24 | /// This represents a section on linux, lots of unix variants and some bare | ||
| 25 | /// metal systems. | ||
| 26 | class MCSectionELF final : public MCSection { | ||
| 27 |   /// This is the sh_type field of a section, drawn from the enums below. | ||
| 28 | unsigned Type; | ||
| 29 | |||
| 30 |   /// This is the sh_flags field of a section, drawn from the enums below. | ||
| 31 | unsigned Flags; | ||
| 32 | |||
| 33 | unsigned UniqueID; | ||
| 34 | |||
| 35 |   /// The size of each entry in this section. This size only makes sense for | ||
| 36 |   /// sections that contain fixed-sized entries. If a section does not contain | ||
| 37 |   /// fixed-sized entries 'EntrySize' will be 0. | ||
| 38 | unsigned EntrySize; | ||
| 39 | |||
| 40 |   /// The section group signature symbol (if not null) and a bool indicating | ||
| 41 |   /// whether this is a GRP_COMDAT group. | ||
| 42 | const PointerIntPair<const MCSymbolELF *, 1, bool> Group; | ||
| 43 | |||
| 44 |   /// Used by SHF_LINK_ORDER. If non-null, the sh_link field will be set to the | ||
| 45 |   /// section header index of the section where LinkedToSym is defined. | ||
| 46 | const MCSymbol *LinkedToSym; | ||
| 47 | |||
| 48 | private: | ||
| 49 | friend class MCContext; | ||
| 50 | |||
| 51 |   // The storage of Name is owned by MCContext's ELFUniquingMap. | ||
| 52 | MCSectionELF(StringRef Name, unsigned type, unsigned flags, SectionKind K, | ||
| 53 | unsigned entrySize, const MCSymbolELF *group, bool IsComdat, | ||
| 54 | unsigned UniqueID, MCSymbol *Begin, | ||
| 55 | const MCSymbolELF *LinkedToSym) | ||
| 56 | : MCSection(SV_ELF, Name, K, Begin), Type(type), Flags(flags), | ||
| 57 | UniqueID(UniqueID), EntrySize(entrySize), Group(group, IsComdat), | ||
| 58 | LinkedToSym(LinkedToSym) { | ||
| 59 | if (Group.getPointer()) | ||
| 60 | Group.getPointer()->setIsSignature(); | ||
| 61 |   } | ||
| 62 | |||
| 63 |   // TODO Delete after we stop supporting generation of GNU-style .zdebug_* | ||
| 64 |   // sections. | ||
| 65 | void setSectionName(StringRef Name) { this->Name = Name; } | ||
| 66 | |||
| 67 | public: | ||
| 68 |   /// Decides whether a '.section' directive should be printed before the | ||
| 69 |   /// section name | ||
| 70 | bool shouldOmitSectionDirective(StringRef Name, const MCAsmInfo &MAI) const; | ||
| 71 | |||
| 72 | unsigned getType() const { return Type; } | ||
| 73 | unsigned getFlags() const { return Flags; } | ||
| 74 | unsigned getEntrySize() const { return EntrySize; } | ||
| 75 | void setFlags(unsigned F) { Flags = F; } | ||
| 76 | const MCSymbolELF *getGroup() const { return Group.getPointer(); } | ||
| 77 | bool isComdat() const { return Group.getInt(); } | ||
| 78 | |||
| 79 | void printSwitchToSection(const MCAsmInfo &MAI, const Triple &T, | ||
| 80 |                             raw_ostream &OS, | ||
| 81 | const MCExpr *Subsection) const override; | ||
| 82 | bool useCodeAlign() const override; | ||
| 83 | bool isVirtualSection() const override; | ||
| 84 | StringRef getVirtualSectionKind() const override; | ||
| 85 | |||
| 86 | bool isUnique() const { return UniqueID != NonUniqueID; } | ||
| 87 | unsigned getUniqueID() const { return UniqueID; } | ||
| 88 | |||
| 89 | const MCSection *getLinkedToSection() const { | ||
| 90 | return &LinkedToSym->getSection(); | ||
| 91 |   } | ||
| 92 | const MCSymbol *getLinkedToSymbol() const { return LinkedToSym; } | ||
| 93 | |||
| 94 | static bool classof(const MCSection *S) { | ||
| 95 | return S->getVariant() == SV_ELF; | ||
| 96 |   } | ||
| 97 | }; | ||
| 98 | |||
| 99 | } // end namespace llvm | ||
| 100 | |||
| 101 | #endif // LLVM_MC_MCSECTIONELF_H |