1 //===--- MemoryTree.h - A special tree for components and sizes -*- 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 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_SUPPORT_MEMORYTREE_H_ 10 #define LLVM_CLANG_TOOLS_EXTRA_CLANGD_SUPPORT_MEMORYTREE_H_ 11 12 #include "Trace.h" 13 #include "llvm/ADT/DenseMap.h" 14 #include "llvm/ADT/STLExtras.h" 15 #include "llvm/ADT/StringRef.h" 16 #include "llvm/Support/Allocator.h" 17 #include "llvm/Support/StringSaver.h" 18 #include <cstddef> 19 #include <string> 20 #include <vector> 21 22 namespace clang { 23 namespace clangd { 24 25 /// A tree that can be used to represent memory usage of nested components while 26 /// preserving the hierarchy. 27 /// Edges have associated names. An edge that might not be interesting to all 28 /// traversers or costly to copy (e.g. file names) can be marked as "detail". 29 /// Tree construction allows chosing between a detailed and brief mode, in brief 30 /// mode all "detail" edges are ignored and tree is constructed without any 31 /// string copies. 32 struct MemoryTree { 33 public: 34 /// If Alloc is nullptr, tree is in brief mode and will ignore detail edges. 35 MemoryTree(llvm::BumpPtrAllocator *DetailAlloc = nullptr) DetailAllocMemoryTree36 : DetailAlloc(DetailAlloc) {} 37 38 /// No copy of the \p Name. 39 /// Note that returned pointers are invalidated with subsequent calls to 40 /// child/detail. childMemoryTree41 MemoryTree &child(llvm::StringLiteral Name) { return createChild(Name); } 42 43 MemoryTree(const MemoryTree &) = delete; 44 MemoryTree &operator=(const MemoryTree &) = delete; 45 46 MemoryTree(MemoryTree &&) = default; 47 MemoryTree &operator=(MemoryTree &&) = default; 48 49 /// Makes a copy of the \p Name in detailed mode, returns current node 50 /// otherwise. 51 /// Note that returned pointers are invalidated with subsequent calls to 52 /// child/detail. detailMemoryTree53 MemoryTree &detail(llvm::StringRef Name) { 54 return DetailAlloc ? createChild(Name.copy(*DetailAlloc)) : *this; 55 } 56 57 /// Increases size of current node by \p Increment. addUsageMemoryTree58 void addUsage(size_t Increment) { Size += Increment; } 59 60 /// Returns edges to direct children of this node. 61 const llvm::DenseMap<llvm::StringRef, MemoryTree> &children() const; 62 63 /// Returns total number of bytes used by this sub-tree. Performs a traversal. 64 size_t total() const; 65 66 /// Returns total number of bytes used by this node only. selfMemoryTree67 size_t self() const { return Size; } 68 69 private: 70 /// Adds a child with an edge labeled as \p Name. Multiple calls to this 71 /// function returns the same node. 72 MemoryTree &createChild(llvm::StringRef Name); 73 74 /// Allocator to use for detailed edge names. 75 llvm::BumpPtrAllocator *DetailAlloc = nullptr; 76 77 /// Bytes owned by this component specifically. 78 size_t Size = 0; 79 80 /// Edges from current node to its children. Keys are the labels for edges. 81 llvm::DenseMap<llvm::StringRef, MemoryTree> Children; 82 }; 83 84 /// Records total memory usage of each node under \p Out. Labels are edges on 85 /// the path joined with ".", starting with \p RootName. 86 void record(const MemoryTree &MT, std::string RootName, 87 const trace::Metric &Out); 88 89 } // namespace clangd 90 } // namespace clang 91 92 #endif 93