[InstCombine] Signed saturation patterns
[llvm-core.git] / include / llvm / MC / MCSection.h
blobd057feda87d8b5818e1a8829449c310709c050d5
1 //===- MCSection.h - 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 MCSection class.
11 //===----------------------------------------------------------------------===//
13 #ifndef LLVM_MC_MCSECTION_H
14 #define LLVM_MC_MCSECTION_H
16 #include "llvm/ADT/SmallVector.h"
17 #include "llvm/ADT/ilist.h"
18 #include "llvm/MC/MCFragment.h"
19 #include "llvm/MC/SectionKind.h"
20 #include "llvm/Support/Alignment.h"
21 #include <cassert>
22 #include <utility>
24 namespace llvm {
26 class MCAsmInfo;
27 class MCContext;
28 class MCExpr;
29 class MCSymbol;
30 class raw_ostream;
31 class Triple;
33 template <> struct ilist_alloc_traits<MCFragment> {
34 static void deleteNode(MCFragment *V);
37 /// Instances of this class represent a uniqued identifier for a section in the
38 /// current translation unit. The MCContext class uniques and creates these.
39 class MCSection {
40 public:
41 enum SectionVariant { SV_COFF = 0, SV_ELF, SV_MachO, SV_Wasm, SV_XCOFF };
43 /// Express the state of bundle locked groups while emitting code.
44 enum BundleLockStateType {
45 NotBundleLocked,
46 BundleLocked,
47 BundleLockedAlignToEnd
50 using FragmentListType = iplist<MCFragment>;
52 using const_iterator = FragmentListType::const_iterator;
53 using iterator = FragmentListType::iterator;
55 using const_reverse_iterator = FragmentListType::const_reverse_iterator;
56 using reverse_iterator = FragmentListType::reverse_iterator;
58 private:
59 MCSymbol *Begin;
60 MCSymbol *End = nullptr;
61 /// The alignment requirement of this section.
62 Align Alignment;
63 /// The section index in the assemblers section list.
64 unsigned Ordinal = 0;
65 /// The index of this section in the layout order.
66 unsigned LayoutOrder;
68 /// Keeping track of bundle-locked state.
69 BundleLockStateType BundleLockState = NotBundleLocked;
71 /// Current nesting depth of bundle_lock directives.
72 unsigned BundleLockNestingDepth = 0;
74 /// We've seen a bundle_lock directive but not its first instruction
75 /// yet.
76 bool BundleGroupBeforeFirstInst : 1;
78 /// Whether this section has had instructions emitted into it.
79 bool HasInstructions : 1;
81 /// Whether this section has had data emitted into it.
82 /// Right now this is only used by the ARM backend.
83 bool HasData : 1;
85 bool IsRegistered : 1;
87 MCDummyFragment DummyFragment;
89 FragmentListType Fragments;
91 /// Mapping from subsection number to insertion point for subsection numbers
92 /// below that number.
93 SmallVector<std::pair<unsigned, MCFragment *>, 1> SubsectionFragmentMap;
95 protected:
96 SectionVariant Variant;
97 SectionKind Kind;
99 MCSection(SectionVariant V, SectionKind K, MCSymbol *Begin);
100 ~MCSection();
102 public:
103 MCSection(const MCSection &) = delete;
104 MCSection &operator=(const MCSection &) = delete;
106 SectionKind getKind() const { return Kind; }
108 SectionVariant getVariant() const { return Variant; }
110 MCSymbol *getBeginSymbol() { return Begin; }
111 const MCSymbol *getBeginSymbol() const {
112 return const_cast<MCSection *>(this)->getBeginSymbol();
114 void setBeginSymbol(MCSymbol *Sym) {
115 assert(!Begin);
116 Begin = Sym;
118 MCSymbol *getEndSymbol(MCContext &Ctx);
119 bool hasEnded() const;
121 unsigned getAlignment() const { return Alignment.value(); }
122 void setAlignment(Align Value) { Alignment = Value; }
124 unsigned getOrdinal() const { return Ordinal; }
125 void setOrdinal(unsigned Value) { Ordinal = Value; }
127 unsigned getLayoutOrder() const { return LayoutOrder; }
128 void setLayoutOrder(unsigned Value) { LayoutOrder = Value; }
130 BundleLockStateType getBundleLockState() const { return BundleLockState; }
131 void setBundleLockState(BundleLockStateType NewState);
132 bool isBundleLocked() const { return BundleLockState != NotBundleLocked; }
134 bool isBundleGroupBeforeFirstInst() const {
135 return BundleGroupBeforeFirstInst;
137 void setBundleGroupBeforeFirstInst(bool IsFirst) {
138 BundleGroupBeforeFirstInst = IsFirst;
141 bool hasInstructions() const { return HasInstructions; }
142 void setHasInstructions(bool Value) { HasInstructions = Value; }
144 bool hasData() const { return HasData; }
145 void setHasData(bool Value) { HasData = Value; }
147 bool isRegistered() const { return IsRegistered; }
148 void setIsRegistered(bool Value) { IsRegistered = Value; }
150 MCSection::FragmentListType &getFragmentList() { return Fragments; }
151 const MCSection::FragmentListType &getFragmentList() const {
152 return const_cast<MCSection *>(this)->getFragmentList();
155 /// Support for MCFragment::getNextNode().
156 static FragmentListType MCSection::*getSublistAccess(MCFragment *) {
157 return &MCSection::Fragments;
160 const MCDummyFragment &getDummyFragment() const { return DummyFragment; }
161 MCDummyFragment &getDummyFragment() { return DummyFragment; }
163 iterator begin() { return Fragments.begin(); }
164 const_iterator begin() const { return Fragments.begin(); }
166 iterator end() { return Fragments.end(); }
167 const_iterator end() const { return Fragments.end(); }
169 reverse_iterator rbegin() { return Fragments.rbegin(); }
170 const_reverse_iterator rbegin() const { return Fragments.rbegin(); }
172 reverse_iterator rend() { return Fragments.rend(); }
173 const_reverse_iterator rend() const { return Fragments.rend(); }
175 MCSection::iterator getSubsectionInsertionPoint(unsigned Subsection);
177 void dump() const;
179 virtual void PrintSwitchToSection(const MCAsmInfo &MAI, const Triple &T,
180 raw_ostream &OS,
181 const MCExpr *Subsection) const = 0;
183 /// Return true if a .align directive should use "optimized nops" to fill
184 /// instead of 0s.
185 virtual bool UseCodeAlign() const = 0;
187 /// Check whether this section is "virtual", that is has no actual object
188 /// file contents.
189 virtual bool isVirtualSection() const = 0;
192 } // end namespace llvm
194 #endif // LLVM_MC_MCSECTION_H