1 //===-------------------------- CodeRegion.h -------------------*- C++ -* -===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 /// \file
10 ///
11 /// This file implements class CodeRegion and CodeRegions.
12 ///
13 /// A CodeRegion describes a region of assembly code guarded by special LLVM-MCA
14 /// comment directives.
15 ///
16 ///   # LLVM-MCA-BEGIN foo
17 ///     ...  ## asm
18 ///   # LLVM-MCA-END
19 ///
20 /// A comment starting with substring LLVM-MCA-BEGIN marks the beginning of a
21 /// new region of code.
22 /// A comment starting with substring LLVM-MCA-END marks the end of the
23 /// last-seen region of code.
24 ///
25 /// Code regions are not allowed to overlap. Each region can have a optional
26 /// description; internally, regions are described by a range of source
27 /// locations (SMLoc objects).
28 ///
29 /// An instruction (a MCInst) is added to a region R only if its location is in
30 /// range [R.RangeStart, R.RangeEnd].
31 //
32 //===----------------------------------------------------------------------===//
33 
34 #ifndef LLVM_TOOLS_LLVM_MCA_CODEREGION_H
35 #define LLVM_TOOLS_LLVM_MCA_CODEREGION_H
36 
37 #include "llvm/ADT/StringRef.h"
38 #include "llvm/MC/MCInst.h"
39 #include "llvm/Support/SMLoc.h"
40 #include "llvm/Support/SourceMgr.h"
41 #include <vector>
42 
43 namespace mca {
44 
45 /// A region of assembly code.
46 ///
47 /// It identifies a sequence of machine instructions.
48 class CodeRegion {
49   // An optional descriptor for this region.
50   llvm::StringRef Description;
51   // Instructions that form this region.
52   std::vector<std::unique_ptr<const llvm::MCInst>> Instructions;
53   // Source location range.
54   llvm::SMLoc RangeStart;
55   llvm::SMLoc RangeEnd;
56 
57   CodeRegion(const CodeRegion &) = delete;
58   CodeRegion &operator=(const CodeRegion &) = delete;
59 
60 public:
CodeRegion(llvm::StringRef Desc,llvm::SMLoc Start)61   CodeRegion(llvm::StringRef Desc, llvm::SMLoc Start)
62       : Description(Desc), RangeStart(Start), RangeEnd() {}
63 
addInstruction(std::unique_ptr<const llvm::MCInst> Instruction)64   void addInstruction(std::unique_ptr<const llvm::MCInst> Instruction) {
65     Instructions.emplace_back(std::move(Instruction));
66   }
67 
startLoc()68   llvm::SMLoc startLoc() const { return RangeStart; }
endLoc()69   llvm::SMLoc endLoc() const { return RangeEnd; }
70 
setEndLocation(llvm::SMLoc End)71   void setEndLocation(llvm::SMLoc End) { RangeEnd = End; }
empty()72   bool empty() const { return Instructions.empty(); }
73   bool isLocInRange(llvm::SMLoc Loc) const;
74 
75   const std::vector<std::unique_ptr<const llvm::MCInst>> &
getInstructions()76   getInstructions() const {
77     return Instructions;
78   }
79 
getDescription()80   llvm::StringRef getDescription() const { return Description; }
81 };
82 
83 class CodeRegions {
84   // A source manager. Used by the tool to generate meaningful warnings.
85   llvm::SourceMgr &SM;
86 
87   std::vector<std::unique_ptr<CodeRegion>> Regions;
88 
89   // Construct a new region of code guarded by LLVM-MCA comments.
addRegion(llvm::StringRef Description,llvm::SMLoc Loc)90   void addRegion(llvm::StringRef Description, llvm::SMLoc Loc) {
91     Regions.emplace_back(llvm::make_unique<CodeRegion>(Description, Loc));
92   }
93 
94   CodeRegions(const CodeRegions &) = delete;
95   CodeRegions &operator=(const CodeRegions &) = delete;
96 
97 public:
98   typedef std::vector<std::unique_ptr<CodeRegion>>::iterator iterator;
99   typedef std::vector<std::unique_ptr<CodeRegion>>::const_iterator
100       const_iterator;
101 
begin()102   iterator begin() { return Regions.begin(); }
end()103   iterator end() { return Regions.end(); }
begin()104   const_iterator begin() const { return Regions.cbegin(); }
end()105   const_iterator end() const { return Regions.cend(); }
106 
107   void beginRegion(llvm::StringRef Description, llvm::SMLoc Loc);
108   void endRegion(llvm::SMLoc Loc);
109   void addInstruction(std::unique_ptr<const llvm::MCInst> Instruction);
110 
CodeRegions(llvm::SourceMgr & S)111   CodeRegions(llvm::SourceMgr &S) : SM(S) {
112     // Create a default region for the input code sequence.
113     addRegion("Default", llvm::SMLoc());
114   }
115 
116   const std::vector<std::unique_ptr<const llvm::MCInst>> &
getInstructionSequence(unsigned Idx)117   getInstructionSequence(unsigned Idx) const {
118     return Regions[Idx]->getInstructions();
119   }
120 
empty()121   bool empty() const {
122     return std::all_of(Regions.begin(), Regions.end(),
123                        [](const std::unique_ptr<CodeRegion> &Region) {
124                          return Region->empty();
125                        });
126   }
127 };
128 
129 } // namespace mca
130 
131 #endif
132