clang  3.8.0
CGLoopInfo.h
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1 //===---- CGLoopInfo.h - LLVM CodeGen for loop metadata -*- 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 //
10 // This is the internal state used for llvm translation for loop statement
11 // metadata.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_CLANG_LIB_CODEGEN_CGLOOPINFO_H
16 #define LLVM_CLANG_LIB_CODEGEN_CGLOOPINFO_H
17 
18 #include "llvm/ADT/ArrayRef.h"
19 #include "llvm/ADT/DenseMap.h"
20 #include "llvm/ADT/SmallVector.h"
21 #include "llvm/IR/Value.h"
22 #include "llvm/Support/Compiler.h"
23 
24 namespace llvm {
25 class BasicBlock;
26 class Instruction;
27 class MDNode;
28 } // end namespace llvm
29 
30 namespace clang {
31 class Attr;
32 class ASTContext;
33 namespace CodeGen {
34 
35 /// \brief Attributes that may be specified on loops.
37  explicit LoopAttributes(bool IsParallel = false);
38  void clear();
39 
40  /// \brief Generate llvm.loop.parallel metadata for loads and stores.
41  bool IsParallel;
42 
43  /// \brief State of loop vectorization or unrolling.
45 
46  /// \brief Value for llvm.loop.vectorize.enable metadata.
48 
49  /// \brief Value for llvm.loop.unroll.* metadata (enable, disable, or full).
51 
52  /// \brief Value for llvm.loop.vectorize.width metadata.
53  unsigned VectorizeWidth;
54 
55  /// \brief Value for llvm.loop.interleave.count metadata.
56  unsigned InterleaveCount;
57 
58  /// \brief llvm.unroll.
59  unsigned UnrollCount;
60 };
61 
62 /// \brief Information used when generating a structured loop.
63 class LoopInfo {
64 public:
65  /// \brief Construct a new LoopInfo for the loop with entry Header.
66  LoopInfo(llvm::BasicBlock *Header, const LoopAttributes &Attrs);
67 
68  /// \brief Get the loop id metadata for this loop.
69  llvm::MDNode *getLoopID() const { return LoopID; }
70 
71  /// \brief Get the header block of this loop.
72  llvm::BasicBlock *getHeader() const { return Header; }
73 
74  /// \brief Get the set of attributes active for this loop.
75  const LoopAttributes &getAttributes() const { return Attrs; }
76 
77 private:
78  /// \brief Loop ID metadata.
79  llvm::MDNode *LoopID;
80  /// \brief Header block of this loop.
81  llvm::BasicBlock *Header;
82  /// \brief The attributes for this loop.
83  LoopAttributes Attrs;
84 };
85 
86 /// \brief A stack of loop information corresponding to loop nesting levels.
87 /// This stack can be used to prepare attributes which are applied when a loop
88 /// is emitted.
90  LoopInfoStack(const LoopInfoStack &) = delete;
91  void operator=(const LoopInfoStack &) = delete;
92 
93 public:
95 
96  /// \brief Begin a new structured loop. The set of staged attributes will be
97  /// applied to the loop and then cleared.
98  void push(llvm::BasicBlock *Header);
99 
100  /// \brief Begin a new structured loop. Stage attributes from the Attrs list.
101  /// The staged attributes are applied to the loop and then cleared.
102  void push(llvm::BasicBlock *Header, clang::ASTContext &Ctx,
104 
105  /// \brief End the current loop.
106  void pop();
107 
108  /// \brief Return the top loop id metadata.
109  llvm::MDNode *getCurLoopID() const { return getInfo().getLoopID(); }
110 
111  /// \brief Return true if the top loop is parallel.
112  bool getCurLoopParallel() const {
113  return hasInfo() ? getInfo().getAttributes().IsParallel : false;
114  }
115 
116  /// \brief Function called by the CodeGenFunction when an instruction is
117  /// created.
118  void InsertHelper(llvm::Instruction *I) const;
119 
120  /// \brief Set the next pushed loop as parallel.
121  void setParallel(bool Enable = true) { StagedAttrs.IsParallel = Enable; }
122 
123  /// \brief Set the next pushed loop 'vectorize.enable'
124  void setVectorizeEnable(bool Enable = true) {
125  StagedAttrs.VectorizeEnable =
127  }
128 
129  /// \brief Set the next pushed loop unroll state.
131  StagedAttrs.UnrollEnable = State;
132  }
133 
134  /// \brief Set the vectorize width for the next loop pushed.
135  void setVectorizeWidth(unsigned W) { StagedAttrs.VectorizeWidth = W; }
136 
137  /// \brief Set the interleave count for the next loop pushed.
138  void setInterleaveCount(unsigned C) { StagedAttrs.InterleaveCount = C; }
139 
140  /// \brief Set the unroll count for the next loop pushed.
141  void setUnrollCount(unsigned C) { StagedAttrs.UnrollCount = C; }
142 
143 private:
144  /// \brief Returns true if there is LoopInfo on the stack.
145  bool hasInfo() const { return !Active.empty(); }
146  /// \brief Return the LoopInfo for the current loop. HasInfo should be called
147  /// first to ensure LoopInfo is present.
148  const LoopInfo &getInfo() const { return Active.back(); }
149  /// \brief The set of attributes that will be applied to the next pushed loop.
150  LoopAttributes StagedAttrs;
151  /// \brief Stack of active loops.
153 };
154 
155 } // end namespace CodeGen
156 } // end namespace clang
157 
158 #endif
void setUnrollCount(unsigned C)
Set the unroll count for the next loop pushed.
Definition: CGLoopInfo.h:141
Attributes that may be specified on loops.
Definition: CGLoopInfo.h:36
Information used when generating a structured loop.
Definition: CGLoopInfo.h:63
LoopAttributes(bool IsParallel=false)
Definition: CGLoopInfo.cpp:87
LVEnableState UnrollEnable
Value for llvm.loop.unroll.* metadata (enable, disable, or full).
Definition: CGLoopInfo.h:50
llvm::BasicBlock * getHeader() const
Get the header block of this loop.
Definition: CGLoopInfo.h:72
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:91
LineState State
unsigned InterleaveCount
Value for llvm.loop.interleave.count metadata.
Definition: CGLoopInfo.h:56
LVEnableState VectorizeEnable
Value for llvm.loop.vectorize.enable metadata.
Definition: CGLoopInfo.h:47
void pop()
End the current loop.
Definition: CGLoopInfo.cpp:224
void setVectorizeWidth(unsigned W)
Set the vectorize width for the next loop pushed.
Definition: CGLoopInfo.h:135
void push(llvm::BasicBlock *Header)
Begin a new structured loop.
detail::InMemoryDirectory::const_iterator I
llvm::MDNode * getLoopID() const
Get the loop id metadata for this loop.
Definition: CGLoopInfo.h:69
friend class ASTContext
Definition: Type.h:4012
bool IsParallel
Generate llvm.loop.parallel metadata for loads and stores.
Definition: CGLoopInfo.h:41
bool getCurLoopParallel() const
Return true if the top loop is parallel.
Definition: CGLoopInfo.h:112
void setInterleaveCount(unsigned C)
Set the interleave count for the next loop pushed.
Definition: CGLoopInfo.h:138
unsigned UnrollCount
llvm.unroll.
Definition: CGLoopInfo.h:59
void setParallel(bool Enable=true)
Set the next pushed loop as parallel.
Definition: CGLoopInfo.h:121
LoopInfo(llvm::BasicBlock *Header, const LoopAttributes &Attrs)
Construct a new LoopInfo for the loop with entry Header.
Definition: CGLoopInfo.cpp:101
A stack of loop information corresponding to loop nesting levels.
Definition: CGLoopInfo.h:89
LVEnableState
State of loop vectorization or unrolling.
Definition: CGLoopInfo.h:44
void InsertHelper(llvm::Instruction *I) const
Function called by the CodeGenFunction when an instruction is created.
Definition: CGLoopInfo.cpp:229
const LoopAttributes & getAttributes() const
Get the set of attributes active for this loop.
Definition: CGLoopInfo.h:75
void setUnrollState(const LoopAttributes::LVEnableState &State)
Set the next pushed loop unroll state.
Definition: CGLoopInfo.h:130
void setVectorizeEnable(bool Enable=true)
Set the next pushed loop 'vectorize.enable'.
Definition: CGLoopInfo.h:124
unsigned VectorizeWidth
Value for llvm.loop.vectorize.width metadata.
Definition: CGLoopInfo.h:53
llvm::MDNode * getCurLoopID() const
Return the top loop id metadata.
Definition: CGLoopInfo.h:109