LLVM 19.0.0git
TrackingMDRef.h
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1//===- llvm/IR/TrackingMDRef.h - Tracking Metadata references ---*- 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// References to metadata that track RAUW.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_IR_TRACKINGMDREF_H
14#define LLVM_IR_TRACKINGMDREF_H
15
16#include "llvm/IR/Metadata.h"
17#include <algorithm>
18#include <cassert>
19
20namespace llvm {
21
22/// Tracking metadata reference.
23///
24/// This class behaves like \a TrackingVH, but for metadata.
26 Metadata *MD = nullptr;
27
28public:
29 TrackingMDRef() = default;
30 explicit TrackingMDRef(Metadata *MD) : MD(MD) { track(); }
31
32 TrackingMDRef(TrackingMDRef &&X) : MD(X.MD) { retrack(X); }
33 TrackingMDRef(const TrackingMDRef &X) : MD(X.MD) { track(); }
34
36 if (&X == this)
37 return *this;
38
39 untrack();
40 MD = X.MD;
41 retrack(X);
42 return *this;
43 }
44
46 if (&X == this)
47 return *this;
48
49 untrack();
50 MD = X.MD;
51 track();
52 return *this;
53 }
54
55 ~TrackingMDRef() { untrack(); }
56
57 Metadata *get() const { return MD; }
58 operator Metadata *() const { return get(); }
59 Metadata *operator->() const { return get(); }
60 Metadata &operator*() const { return *get(); }
61
62 void reset() {
63 untrack();
64 MD = nullptr;
65 }
66 void reset(Metadata *MD) {
67 untrack();
68 this->MD = MD;
69 track();
70 }
71
72 /// Check whether this has a trivial destructor.
73 ///
74 /// If \c MD isn't replaceable, the destructor will be a no-op.
75 bool hasTrivialDestructor() const {
76 return !MD || !MetadataTracking::isReplaceable(*MD);
77 }
78
79 bool operator==(const TrackingMDRef &X) const { return MD == X.MD; }
80 bool operator!=(const TrackingMDRef &X) const { return MD != X.MD; }
81
82private:
83 void track() {
84 if (MD)
86 }
87
88 void untrack() {
89 if (MD)
91 }
92
93 void retrack(TrackingMDRef &X) {
94 assert(MD == X.MD && "Expected values to match");
95 if (X.MD) {
97 X.MD = nullptr;
98 }
99 }
100};
101
102/// Typed tracking ref.
103///
104/// Track refererences of a particular type. It's useful to use this for \a
105/// MDNode and \a ValueAsMetadata.
106template <class T> class TypedTrackingMDRef {
107 TrackingMDRef Ref;
108
109public:
111 explicit TypedTrackingMDRef(T *MD) : Ref(static_cast<Metadata *>(MD)) {}
112
115
117 Ref = std::move(X.Ref);
118 return *this;
119 }
120
122 Ref = X.Ref;
123 return *this;
124 }
125
126 T *get() const { return (T *)Ref.get(); }
127 operator T *() const { return get(); }
128 T *operator->() const { return get(); }
129 T &operator*() const { return *get(); }
130
131 bool operator==(const TypedTrackingMDRef &X) const { return Ref == X.Ref; }
132 bool operator!=(const TypedTrackingMDRef &X) const { return Ref != X.Ref; }
133
134 void reset() { Ref.reset(); }
135 void reset(T *MD) { Ref.reset(static_cast<Metadata *>(MD)); }
136
137 /// Check whether this has a trivial destructor.
138 bool hasTrivialDestructor() const { return Ref.hasTrivialDestructor(); }
139};
140
143
144// Expose the underlying metadata to casting.
145template <> struct simplify_type<TrackingMDRef> {
147
148 static SimpleType getSimplifiedValue(TrackingMDRef &MD) { return MD.get(); }
149};
150
151template <> struct simplify_type<const TrackingMDRef> {
153
155 return MD.get();
156 }
157};
158
159template <class T> struct simplify_type<TypedTrackingMDRef<T>> {
160 using SimpleType = T *;
161
163 return MD.get();
164 }
165};
166
167template <class T> struct simplify_type<const TypedTrackingMDRef<T>> {
168 using SimpleType = T *;
169
171 return MD.get();
172 }
173};
174
175} // end namespace llvm
176
177#endif // LLVM_IR_TRACKINGMDREF_H
aarch64 promote const
static GCMetadataPrinterRegistry::Add< ErlangGCPrinter > X("erlang", "erlang-compatible garbage collector")
This file contains the declarations for metadata subclasses.
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
static bool isReplaceable(const Metadata &MD)
Check whether metadata is replaceable.
Definition: Metadata.cpp:246
static void untrack(Metadata *&MD)
Stop tracking a reference to metadata.
Definition: Metadata.h:349
static bool retrack(Metadata *&MD, Metadata *&New)
Move tracking from one reference to another.
Definition: Metadata.h:360
static bool track(Metadata *&MD)
Track the reference to metadata.
Definition: Metadata.h:315
Root of the metadata hierarchy.
Definition: Metadata.h:62
Tracking metadata reference.
Definition: TrackingMDRef.h:25
TrackingMDRef(const TrackingMDRef &X)
Definition: TrackingMDRef.h:33
Metadata & operator*() const
Definition: TrackingMDRef.h:60
bool operator==(const TrackingMDRef &X) const
Definition: TrackingMDRef.h:79
bool hasTrivialDestructor() const
Check whether this has a trivial destructor.
Definition: TrackingMDRef.h:75
TrackingMDRef(Metadata *MD)
Definition: TrackingMDRef.h:30
TrackingMDRef()=default
bool operator!=(const TrackingMDRef &X) const
Definition: TrackingMDRef.h:80
Metadata * get() const
Definition: TrackingMDRef.h:57
void reset(Metadata *MD)
Definition: TrackingMDRef.h:66
TrackingMDRef(TrackingMDRef &&X)
Definition: TrackingMDRef.h:32
Metadata * operator->() const
Definition: TrackingMDRef.h:59
TrackingMDRef & operator=(const TrackingMDRef &X)
Definition: TrackingMDRef.h:45
TrackingMDRef & operator=(TrackingMDRef &&X)
Definition: TrackingMDRef.h:35
Typed tracking ref.
bool operator!=(const TypedTrackingMDRef &X) const
TypedTrackingMDRef(TypedTrackingMDRef &&X)
bool operator==(const TypedTrackingMDRef &X) const
TypedTrackingMDRef(const TypedTrackingMDRef &X)
TypedTrackingMDRef & operator=(const TypedTrackingMDRef &X)
TypedTrackingMDRef & operator=(TypedTrackingMDRef &&X)
bool hasTrivialDestructor() const
Check whether this has a trivial destructor.
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
OutputIt move(R &&Range, OutputIt Out)
Provide wrappers to std::move which take ranges instead of having to pass begin/end explicitly.
Definition: STLExtras.h:1858
Implement std::hash so that hash_code can be used in STL containers.
Definition: BitVector.h:858
static SimpleType getSimplifiedValue(TrackingMDRef &MD)
static SimpleType getSimplifiedValue(TypedTrackingMDRef< T > &MD)
static SimpleType getSimplifiedValue(const TrackingMDRef &MD)
static SimpleType getSimplifiedValue(const TypedTrackingMDRef< T > &MD)
Define a template that can be specialized by smart pointers to reflect the fact that they are automat...
Definition: Casting.h:34