1 //===- Profile.h - XRay Profile Abstraction -------------------------------===//
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
7 //===----------------------------------------------------------------------===//
9 // Defines the XRay Profile class representing the latency profile generated by
10 // XRay's profiling mode.
12 //===----------------------------------------------------------------------===//
13 #ifndef LLVM_XRAY_PROFILE_H
14 #define LLVM_XRAY_PROFILE_H
16 #include "llvm/ADT/DenseMap.h"
17 #include "llvm/ADT/SmallVector.h"
18 #include "llvm/ADT/StringRef.h"
19 #include "llvm/Support/Error.h"
29 // We forward declare the Trace type for turning a Trace into a Profile.
32 /// This function will attempt to load an XRay Profiling Mode profile from the
33 /// provided |Filename|.
35 /// For any errors encountered in the loading of the profile data from
36 /// |Filename|, this function will return an Error condition appropriately.
37 Expected<Profile> loadProfile(StringRef Filename);
39 /// This algorithm will merge two Profile instances into a single Profile
40 /// instance, aggregating blocks by Thread ID.
41 Profile mergeProfilesByThread(const Profile &L, const Profile &R);
43 /// This algorithm will merge two Profile instances into a single Profile
44 /// instance, aggregating blocks by function call stack.
45 Profile mergeProfilesByStack(const Profile &L, const Profile &R);
47 /// This function takes a Trace and creates a Profile instance from it.
48 Expected<Profile> profileFromTrace(const Trace &T);
50 /// Profile instances are thread-compatible.
53 using ThreadID = uint64_t;
54 using PathID = unsigned;
55 using FuncID = int32_t;
59 uint64_t CumulativeLocalTime;
64 std::vector<std::pair<PathID, Data>> PathData;
67 /// Provides a sequence of function IDs from a previously interned PathID.
69 /// Returns an error if |P| had not been interned before into the Profile.
71 Expected<std::vector<FuncID>> expandPath(PathID P) const;
73 /// The stack represented in |P| must be in stack order (leaf to root). This
74 /// will always return the same PathID for |P| that has the same sequence.
75 PathID internPath(ArrayRef<FuncID> P);
77 /// Appends a fully-formed Block instance into the Profile.
79 /// Returns an error condition in the following cases:
81 /// - The PathData component of the Block is empty
83 Error addBlock(Block &&B);
88 Profile(Profile &&O) noexcept
89 : Blocks(std::move(O.Blocks)), NodeStorage(std::move(O.NodeStorage)),
90 Roots(std::move(O.Roots)), PathIDMap(std::move(O.PathIDMap)),
93 Profile &operator=(Profile &&O) noexcept {
94 Blocks = std::move(O.Blocks);
95 NodeStorage = std::move(O.NodeStorage);
96 Roots = std::move(O.Roots);
97 PathIDMap = std::move(O.PathIDMap);
102 Profile(const Profile &);
103 Profile &operator=(const Profile &);
105 friend void swap(Profile &L, Profile &R) {
107 swap(L.Blocks, R.Blocks);
108 swap(L.NodeStorage, R.NodeStorage);
109 swap(L.Roots, R.Roots);
110 swap(L.PathIDMap, R.PathIDMap);
111 swap(L.NextID, R.NextID);
115 using BlockList = std::list<Block>;
119 std::vector<TrieNode *> Callees{};
120 TrieNode *Caller = nullptr;
124 // List of blocks associated with a Profile.
127 // List of TrieNode elements we've seen.
128 std::list<TrieNode> NodeStorage;
130 // List of call stack roots.
131 SmallVector<TrieNode *, 4> Roots;
133 // Reverse mapping between a PathID to a TrieNode*.
134 DenseMap<PathID, TrieNode *> PathIDMap;
136 // Used to identify paths.
140 using const_iterator = BlockList::const_iterator;
141 const_iterator begin() const { return Blocks.begin(); }
142 const_iterator end() const { return Blocks.end(); }
143 bool empty() const { return Blocks.empty(); }