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Diffstat (limited to 'third_party/llvm-project/include/llvm/MC/MCFragment.h')
-rw-r--r-- | third_party/llvm-project/include/llvm/MC/MCFragment.h | 663 |
1 files changed, 663 insertions, 0 deletions
diff --git a/third_party/llvm-project/include/llvm/MC/MCFragment.h b/third_party/llvm-project/include/llvm/MC/MCFragment.h new file mode 100644 index 000000000..b0def566c --- /dev/null +++ b/third_party/llvm-project/include/llvm/MC/MCFragment.h @@ -0,0 +1,663 @@ +//===- MCFragment.h - Fragment type hierarchy -------------------*- 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_MCFRAGMENT_H +#define LLVM_MC_MCFRAGMENT_H + +#include "llvm/ADT/ArrayRef.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/ADT/ilist_node.h" +#include "llvm/MC/MCFixup.h" +#include "llvm/MC/MCInst.h" +#include "llvm/Support/Casting.h" +#include "llvm/Support/SMLoc.h" +#include <cstdint> +#include <utility> + +namespace llvm { + +class MCSection; +class MCSubtargetInfo; +class MCSymbol; + +class MCFragment : public ilist_node_with_parent<MCFragment, MCSection> { + friend class MCAsmLayout; + +public: + enum FragmentType : uint8_t { + FT_Align, + FT_Data, + FT_CompactEncodedInst, + FT_Fill, + FT_Relaxable, + FT_Org, + FT_Dwarf, + FT_DwarfFrame, + FT_LEB, + FT_Padding, + FT_SymbolId, + FT_CVInlineLines, + FT_CVDefRange, + FT_Dummy + }; + +private: + FragmentType Kind; + +protected: + bool HasInstructions; + +private: + /// LayoutOrder - The layout order of this fragment. + unsigned LayoutOrder; + + /// The data for the section this fragment is in. + MCSection *Parent; + + /// Atom - The atom this fragment is in, as represented by its defining + /// symbol. + const MCSymbol *Atom; + + /// \name Assembler Backend Data + /// @{ + // + // FIXME: This could all be kept private to the assembler implementation. + + /// Offset - The offset of this fragment in its section. This is ~0 until + /// initialized. + uint64_t Offset; + + /// @} + +protected: + MCFragment(FragmentType Kind, bool HasInstructions, + MCSection *Parent = nullptr); + + ~MCFragment(); + +public: + MCFragment() = delete; + MCFragment(const MCFragment &) = delete; + MCFragment &operator=(const MCFragment &) = delete; + + /// Destroys the current fragment. + /// + /// This must be used instead of delete as MCFragment is non-virtual. + /// This method will dispatch to the appropriate subclass. + void destroy(); + + FragmentType getKind() const { return Kind; } + + MCSection *getParent() const { return Parent; } + void setParent(MCSection *Value) { Parent = Value; } + + const MCSymbol *getAtom() const { return Atom; } + void setAtom(const MCSymbol *Value) { Atom = Value; } + + unsigned getLayoutOrder() const { return LayoutOrder; } + void setLayoutOrder(unsigned Value) { LayoutOrder = Value; } + + /// Does this fragment have instructions emitted into it? By default + /// this is false, but specific fragment types may set it to true. + bool hasInstructions() const { return HasInstructions; } + + /// Return true if given frgment has FT_Dummy type. + bool isDummy() const { return Kind == FT_Dummy; } + + void dump() const; +}; + +class MCDummyFragment : public MCFragment { +public: + explicit MCDummyFragment(MCSection *Sec) : MCFragment(FT_Dummy, false, Sec) {} + + static bool classof(const MCFragment *F) { return F->getKind() == FT_Dummy; } +}; + +/// Interface implemented by fragments that contain encoded instructions and/or +/// data. +/// +class MCEncodedFragment : public MCFragment { + /// Should this fragment be aligned to the end of a bundle? + bool AlignToBundleEnd = false; + + uint8_t BundlePadding = 0; + +protected: + MCEncodedFragment(MCFragment::FragmentType FType, bool HasInstructions, + MCSection *Sec) + : MCFragment(FType, HasInstructions, Sec) {} + + /// STI - The MCSubtargetInfo in effect when the instruction was encoded. + /// must be non-null for instructions. + const MCSubtargetInfo *STI = nullptr; + +public: + static bool classof(const MCFragment *F) { + MCFragment::FragmentType Kind = F->getKind(); + switch (Kind) { + default: + return false; + case MCFragment::FT_Relaxable: + case MCFragment::FT_CompactEncodedInst: + case MCFragment::FT_Data: + case MCFragment::FT_Dwarf: + case MCFragment::FT_DwarfFrame: + return true; + } + } + + /// Should this fragment be placed at the end of an aligned bundle? + bool alignToBundleEnd() const { return AlignToBundleEnd; } + void setAlignToBundleEnd(bool V) { AlignToBundleEnd = V; } + + /// Get the padding size that must be inserted before this fragment. + /// Used for bundling. By default, no padding is inserted. + /// Note that padding size is restricted to 8 bits. This is an optimization + /// to reduce the amount of space used for each fragment. In practice, larger + /// padding should never be required. + uint8_t getBundlePadding() const { return BundlePadding; } + + /// Set the padding size for this fragment. By default it's a no-op, + /// and only some fragments have a meaningful implementation. + void setBundlePadding(uint8_t N) { BundlePadding = N; } + + /// Retrieve the MCSubTargetInfo in effect when the instruction was encoded. + /// Guaranteed to be non-null if hasInstructions() == true + const MCSubtargetInfo *getSubtargetInfo() const { return STI; } + + /// Record that the fragment contains instructions with the MCSubtargetInfo in + /// effect when the instruction was encoded. + void setHasInstructions(const MCSubtargetInfo &STI) { + HasInstructions = true; + this->STI = &STI; + } +}; + +/// Interface implemented by fragments that contain encoded instructions and/or +/// data. +/// +template<unsigned ContentsSize> +class MCEncodedFragmentWithContents : public MCEncodedFragment { + SmallVector<char, ContentsSize> Contents; + +protected: + MCEncodedFragmentWithContents(MCFragment::FragmentType FType, + bool HasInstructions, + MCSection *Sec) + : MCEncodedFragment(FType, HasInstructions, Sec) {} + +public: + SmallVectorImpl<char> &getContents() { return Contents; } + const SmallVectorImpl<char> &getContents() const { return Contents; } +}; + +/// Interface implemented by fragments that contain encoded instructions and/or +/// data and also have fixups registered. +/// +template<unsigned ContentsSize, unsigned FixupsSize> +class MCEncodedFragmentWithFixups : + public MCEncodedFragmentWithContents<ContentsSize> { + + /// Fixups - The list of fixups in this fragment. + SmallVector<MCFixup, FixupsSize> Fixups; + +protected: + MCEncodedFragmentWithFixups(MCFragment::FragmentType FType, + bool HasInstructions, + MCSection *Sec) + : MCEncodedFragmentWithContents<ContentsSize>(FType, HasInstructions, + Sec) {} + +public: + + using const_fixup_iterator = SmallVectorImpl<MCFixup>::const_iterator; + using fixup_iterator = SmallVectorImpl<MCFixup>::iterator; + + SmallVectorImpl<MCFixup> &getFixups() { return Fixups; } + const SmallVectorImpl<MCFixup> &getFixups() const { return Fixups; } + + fixup_iterator fixup_begin() { return Fixups.begin(); } + const_fixup_iterator fixup_begin() const { return Fixups.begin(); } + + fixup_iterator fixup_end() { return Fixups.end(); } + const_fixup_iterator fixup_end() const { return Fixups.end(); } + + static bool classof(const MCFragment *F) { + MCFragment::FragmentType Kind = F->getKind(); + return Kind == MCFragment::FT_Relaxable || Kind == MCFragment::FT_Data || + Kind == MCFragment::FT_CVDefRange || Kind == MCFragment::FT_Dwarf || + Kind == MCFragment::FT_DwarfFrame; + } +}; + +/// Fragment for data and encoded instructions. +/// +class MCDataFragment : public MCEncodedFragmentWithFixups<32, 4> { +public: + MCDataFragment(MCSection *Sec = nullptr) + : MCEncodedFragmentWithFixups<32, 4>(FT_Data, false, Sec) {} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_Data; + } +}; + +/// This is a compact (memory-size-wise) fragment for holding an encoded +/// instruction (non-relaxable) that has no fixups registered. When applicable, +/// it can be used instead of MCDataFragment and lead to lower memory +/// consumption. +/// +class MCCompactEncodedInstFragment : public MCEncodedFragmentWithContents<4> { +public: + MCCompactEncodedInstFragment(MCSection *Sec = nullptr) + : MCEncodedFragmentWithContents(FT_CompactEncodedInst, true, Sec) { + } + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_CompactEncodedInst; + } +}; + +/// A relaxable fragment holds on to its MCInst, since it may need to be +/// relaxed during the assembler layout and relaxation stage. +/// +class MCRelaxableFragment : public MCEncodedFragmentWithFixups<8, 1> { + + /// Inst - The instruction this is a fragment for. + MCInst Inst; + +public: + MCRelaxableFragment(const MCInst &Inst, const MCSubtargetInfo &STI, + MCSection *Sec = nullptr) + : MCEncodedFragmentWithFixups(FT_Relaxable, true, Sec), + Inst(Inst) { this->STI = &STI; } + + const MCInst &getInst() const { return Inst; } + void setInst(const MCInst &Value) { Inst = Value; } + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_Relaxable; + } +}; + +class MCAlignFragment : public MCFragment { + /// Alignment - The alignment to ensure, in bytes. + unsigned Alignment; + + /// EmitNops - Flag to indicate that (optimal) NOPs should be emitted instead + /// of using the provided value. The exact interpretation of this flag is + /// target dependent. + bool EmitNops : 1; + + /// Value - Value to use for filling padding bytes. + int64_t Value; + + /// ValueSize - The size of the integer (in bytes) of \p Value. + unsigned ValueSize; + + /// MaxBytesToEmit - The maximum number of bytes to emit; if the alignment + /// cannot be satisfied in this width then this fragment is ignored. + unsigned MaxBytesToEmit; + +public: + MCAlignFragment(unsigned Alignment, int64_t Value, unsigned ValueSize, + unsigned MaxBytesToEmit, MCSection *Sec = nullptr) + : MCFragment(FT_Align, false, Sec), Alignment(Alignment), EmitNops(false), + Value(Value), ValueSize(ValueSize), MaxBytesToEmit(MaxBytesToEmit) {} + + /// \name Accessors + /// @{ + + unsigned getAlignment() const { return Alignment; } + + int64_t getValue() const { return Value; } + + unsigned getValueSize() const { return ValueSize; } + + unsigned getMaxBytesToEmit() const { return MaxBytesToEmit; } + + bool hasEmitNops() const { return EmitNops; } + void setEmitNops(bool Value) { EmitNops = Value; } + + /// @} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_Align; + } +}; + +/// Fragment for adding required padding. +/// This fragment is always inserted before an instruction, and holds that +/// instruction as context information (as well as a mask of kinds) for +/// determining the padding size. +/// +class MCPaddingFragment : public MCFragment { + /// A mask containing all the kinds relevant to this fragment. i.e. the i'th + /// bit will be set iff kind i is relevant to this fragment. + uint64_t PaddingPoliciesMask; + /// A boolean indicating if this fragment will actually hold padding. If its + /// value is false, then this fragment serves only as a placeholder, + /// containing data to assist other insertion point in their decision making. + bool IsInsertionPoint; + + uint64_t Size; + + struct MCInstInfo { + bool IsInitialized; + MCInst Inst; + /// A boolean indicating whether the instruction pointed by this fragment is + /// a fixed size instruction or a relaxable instruction held by a + /// MCRelaxableFragment. + bool IsImmutableSizedInst; + union { + /// If the instruction is a fixed size instruction, hold its size. + size_t InstSize; + /// Otherwise, hold a pointer to the MCRelaxableFragment holding it. + MCRelaxableFragment *InstFragment; + }; + }; + MCInstInfo InstInfo; + +public: + static const uint64_t PFK_None = UINT64_C(0); + + enum MCPaddingFragmentKind { + // values 0-7 are reserved for future target independet values. + + FirstTargetPerfNopFragmentKind = 8, + + /// Limit range of target MCPerfNopFragment kinds to fit in uint64_t + MaxTargetPerfNopFragmentKind = 63 + }; + + MCPaddingFragment(MCSection *Sec = nullptr) + : MCFragment(FT_Padding, false, Sec), PaddingPoliciesMask(PFK_None), + IsInsertionPoint(false), Size(UINT64_C(0)), + InstInfo({false, MCInst(), false, {0}}) {} + + bool isInsertionPoint() const { return IsInsertionPoint; } + void setAsInsertionPoint() { IsInsertionPoint = true; } + uint64_t getPaddingPoliciesMask() const { return PaddingPoliciesMask; } + void setPaddingPoliciesMask(uint64_t Value) { PaddingPoliciesMask = Value; } + bool hasPaddingPolicy(uint64_t PolicyMask) const { + assert(isPowerOf2_64(PolicyMask) && + "Policy mask must contain exactly one policy"); + return (getPaddingPoliciesMask() & PolicyMask) != PFK_None; + } + const MCInst &getInst() const { + assert(isInstructionInitialized() && "Fragment has no instruction!"); + return InstInfo.Inst; + } + size_t getInstSize() const { + assert(isInstructionInitialized() && "Fragment has no instruction!"); + if (InstInfo.IsImmutableSizedInst) + return InstInfo.InstSize; + assert(InstInfo.InstFragment != nullptr && + "Must have a valid InstFragment to retrieve InstSize from"); + return InstInfo.InstFragment->getContents().size(); + } + void setInstAndInstSize(const MCInst &Inst, size_t InstSize) { + InstInfo.IsInitialized = true; + InstInfo.IsImmutableSizedInst = true; + InstInfo.Inst = Inst; + InstInfo.InstSize = InstSize; + } + void setInstAndInstFragment(const MCInst &Inst, + MCRelaxableFragment *InstFragment) { + InstInfo.IsInitialized = true; + InstInfo.IsImmutableSizedInst = false; + InstInfo.Inst = Inst; + InstInfo.InstFragment = InstFragment; + } + uint64_t getSize() const { return Size; } + void setSize(uint64_t Value) { Size = Value; } + bool isInstructionInitialized() const { return InstInfo.IsInitialized; } + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_Padding; + } +}; + +class MCFillFragment : public MCFragment { + /// Value to use for filling bytes. + uint64_t Value; + uint8_t ValueSize; + /// The number of bytes to insert. + const MCExpr &NumValues; + + /// Source location of the directive that this fragment was created for. + SMLoc Loc; + +public: + MCFillFragment(uint64_t Value, uint8_t VSize, const MCExpr &NumValues, + SMLoc Loc, MCSection *Sec = nullptr) + : MCFragment(FT_Fill, false, Sec), Value(Value), ValueSize(VSize), + NumValues(NumValues), Loc(Loc) {} + + uint64_t getValue() const { return Value; } + uint8_t getValueSize() const { return ValueSize; } + const MCExpr &getNumValues() const { return NumValues; } + + SMLoc getLoc() const { return Loc; } + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_Fill; + } +}; + +class MCOrgFragment : public MCFragment { + /// The offset this fragment should start at. + const MCExpr *Offset; + + /// Value to use for filling bytes. + int8_t Value; + + /// Source location of the directive that this fragment was created for. + SMLoc Loc; + +public: + MCOrgFragment(const MCExpr &Offset, int8_t Value, SMLoc Loc, + MCSection *Sec = nullptr) + : MCFragment(FT_Org, false, Sec), Offset(&Offset), Value(Value), Loc(Loc) {} + + /// \name Accessors + /// @{ + + const MCExpr &getOffset() const { return *Offset; } + + uint8_t getValue() const { return Value; } + + SMLoc getLoc() const { return Loc; } + + /// @} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_Org; + } +}; + +class MCLEBFragment : public MCFragment { + /// Value - The value this fragment should contain. + const MCExpr *Value; + + /// IsSigned - True if this is a sleb128, false if uleb128. + bool IsSigned; + + SmallString<8> Contents; + +public: + MCLEBFragment(const MCExpr &Value_, bool IsSigned_, MCSection *Sec = nullptr) + : MCFragment(FT_LEB, false, Sec), Value(&Value_), IsSigned(IsSigned_) { + Contents.push_back(0); + } + + /// \name Accessors + /// @{ + + const MCExpr &getValue() const { return *Value; } + + bool isSigned() const { return IsSigned; } + + SmallString<8> &getContents() { return Contents; } + const SmallString<8> &getContents() const { return Contents; } + + /// @} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_LEB; + } +}; + +class MCDwarfLineAddrFragment : public MCEncodedFragmentWithFixups<8, 1> { + /// LineDelta - the value of the difference between the two line numbers + /// between two .loc dwarf directives. + int64_t LineDelta; + + /// AddrDelta - The expression for the difference of the two symbols that + /// make up the address delta between two .loc dwarf directives. + const MCExpr *AddrDelta; + +public: + MCDwarfLineAddrFragment(int64_t LineDelta, const MCExpr &AddrDelta, + MCSection *Sec = nullptr) + : MCEncodedFragmentWithFixups<8, 1>(FT_Dwarf, false, Sec), + LineDelta(LineDelta), AddrDelta(&AddrDelta) {} + + /// \name Accessors + /// @{ + + int64_t getLineDelta() const { return LineDelta; } + + const MCExpr &getAddrDelta() const { return *AddrDelta; } + + /// @} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_Dwarf; + } +}; + +class MCDwarfCallFrameFragment : public MCEncodedFragmentWithFixups<8, 1> { + /// AddrDelta - The expression for the difference of the two symbols that + /// make up the address delta between two .cfi_* dwarf directives. + const MCExpr *AddrDelta; + +public: + MCDwarfCallFrameFragment(const MCExpr &AddrDelta, MCSection *Sec = nullptr) + : MCEncodedFragmentWithFixups<8, 1>(FT_DwarfFrame, false, Sec), + AddrDelta(&AddrDelta) {} + + /// \name Accessors + /// @{ + + const MCExpr &getAddrDelta() const { return *AddrDelta; } + + /// @} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_DwarfFrame; + } +}; + +/// Represents a symbol table index fragment. +class MCSymbolIdFragment : public MCFragment { + const MCSymbol *Sym; + +public: + MCSymbolIdFragment(const MCSymbol *Sym, MCSection *Sec = nullptr) + : MCFragment(FT_SymbolId, false, Sec), Sym(Sym) {} + + /// \name Accessors + /// @{ + + const MCSymbol *getSymbol() { return Sym; } + const MCSymbol *getSymbol() const { return Sym; } + + /// @} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_SymbolId; + } +}; + +/// Fragment representing the binary annotations produced by the +/// .cv_inline_linetable directive. +class MCCVInlineLineTableFragment : public MCFragment { + unsigned SiteFuncId; + unsigned StartFileId; + unsigned StartLineNum; + const MCSymbol *FnStartSym; + const MCSymbol *FnEndSym; + SmallString<8> Contents; + + /// CodeViewContext has the real knowledge about this format, so let it access + /// our members. + friend class CodeViewContext; + +public: + MCCVInlineLineTableFragment(unsigned SiteFuncId, unsigned StartFileId, + unsigned StartLineNum, const MCSymbol *FnStartSym, + const MCSymbol *FnEndSym, + MCSection *Sec = nullptr) + : MCFragment(FT_CVInlineLines, false, Sec), SiteFuncId(SiteFuncId), + StartFileId(StartFileId), StartLineNum(StartLineNum), + FnStartSym(FnStartSym), FnEndSym(FnEndSym) {} + + /// \name Accessors + /// @{ + + const MCSymbol *getFnStartSym() const { return FnStartSym; } + const MCSymbol *getFnEndSym() const { return FnEndSym; } + + SmallString<8> &getContents() { return Contents; } + const SmallString<8> &getContents() const { return Contents; } + + /// @} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_CVInlineLines; + } +}; + +/// Fragment representing the .cv_def_range directive. +class MCCVDefRangeFragment : public MCEncodedFragmentWithFixups<32, 4> { + SmallVector<std::pair<const MCSymbol *, const MCSymbol *>, 2> Ranges; + SmallString<32> FixedSizePortion; + + /// CodeViewContext has the real knowledge about this format, so let it access + /// our members. + friend class CodeViewContext; + +public: + MCCVDefRangeFragment( + ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges, + StringRef FixedSizePortion, MCSection *Sec = nullptr) + : MCEncodedFragmentWithFixups<32, 4>(FT_CVDefRange, false, Sec), + Ranges(Ranges.begin(), Ranges.end()), + FixedSizePortion(FixedSizePortion) {} + + /// \name Accessors + /// @{ + ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> getRanges() const { + return Ranges; + } + + StringRef getFixedSizePortion() const { return FixedSizePortion; } + /// @} + + static bool classof(const MCFragment *F) { + return F->getKind() == MCFragment::FT_CVDefRange; + } +}; + +} // end namespace llvm + +#endif // LLVM_MC_MCFRAGMENT_H |