clang  3.9.0
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/DebugLoc.h"
22 #include "llvm/IR/Value.h"
23 #include "llvm/Support/Compiler.h"
24 
25 namespace llvm {
26 class BasicBlock;
27 class Instruction;
28 class MDNode;
29 } // end namespace llvm
30 
31 namespace clang {
32 class Attr;
33 class ASTContext;
34 namespace CodeGen {
35 
36 /// \brief Attributes that may be specified on loops.
38  explicit LoopAttributes(bool IsParallel = false);
39  void clear();
40 
41  /// \brief Generate llvm.loop.parallel metadata for loads and stores.
42  bool IsParallel;
43 
44  /// \brief State of loop vectorization or unrolling.
46 
47  /// \brief Value for llvm.loop.vectorize.enable metadata.
49 
50  /// \brief Value for llvm.loop.unroll.* metadata (enable, disable, or full).
52 
53  /// \brief Value for llvm.loop.vectorize.width metadata.
54  unsigned VectorizeWidth;
55 
56  /// \brief Value for llvm.loop.interleave.count metadata.
57  unsigned InterleaveCount;
58 
59  /// \brief llvm.unroll.
60  unsigned UnrollCount;
61 
62  /// \brief Value for llvm.loop.distribute.enable metadata.
64 };
65 
66 /// \brief Information used when generating a structured loop.
67 class LoopInfo {
68 public:
69  /// \brief Construct a new LoopInfo for the loop with entry Header.
70  LoopInfo(llvm::BasicBlock *Header, const LoopAttributes &Attrs,
71  llvm::DebugLoc Location);
72 
73  /// \brief Get the loop id metadata for this loop.
74  llvm::MDNode *getLoopID() const { return LoopID; }
75 
76  /// \brief Get the header block of this loop.
77  llvm::BasicBlock *getHeader() const { return Header; }
78 
79  /// \brief Get the set of attributes active for this loop.
80  const LoopAttributes &getAttributes() const { return Attrs; }
81 
82 private:
83  /// \brief Loop ID metadata.
84  llvm::MDNode *LoopID;
85  /// \brief Header block of this loop.
86  llvm::BasicBlock *Header;
87  /// \brief The attributes for this loop.
88  LoopAttributes Attrs;
89 };
90 
91 /// \brief A stack of loop information corresponding to loop nesting levels.
92 /// This stack can be used to prepare attributes which are applied when a loop
93 /// is emitted.
95  LoopInfoStack(const LoopInfoStack &) = delete;
96  void operator=(const LoopInfoStack &) = delete;
97 
98 public:
100 
101  /// \brief Begin a new structured loop. The set of staged attributes will be
102  /// applied to the loop and then cleared.
103  void push(llvm::BasicBlock *Header,
104  llvm::DebugLoc Location = llvm::DebugLoc());
105 
106  /// \brief Begin a new structured loop. Stage attributes from the Attrs list.
107  /// The staged attributes are applied to the loop and then cleared.
108  void push(llvm::BasicBlock *Header, clang::ASTContext &Ctx,
110  llvm::DebugLoc Location = llvm::DebugLoc());
111 
112  /// \brief End the current loop.
113  void pop();
114 
115  /// \brief Return the top loop id metadata.
116  llvm::MDNode *getCurLoopID() const { return getInfo().getLoopID(); }
117 
118  /// \brief Return true if the top loop is parallel.
119  bool getCurLoopParallel() const {
120  return hasInfo() ? getInfo().getAttributes().IsParallel : false;
121  }
122 
123  /// \brief Function called by the CodeGenFunction when an instruction is
124  /// created.
125  void InsertHelper(llvm::Instruction *I) const;
126 
127  /// \brief Set the next pushed loop as parallel.
128  void setParallel(bool Enable = true) { StagedAttrs.IsParallel = Enable; }
129 
130  /// \brief Set the next pushed loop 'vectorize.enable'
131  void setVectorizeEnable(bool Enable = true) {
132  StagedAttrs.VectorizeEnable =
134  }
135 
136  /// \brief Set the next pushed loop as a distribution candidate.
137  void setDistributeState(bool Enable = true) {
138  StagedAttrs.DistributeEnable =
140  }
141 
142  /// \brief Set the next pushed loop unroll state.
144  StagedAttrs.UnrollEnable = State;
145  }
146 
147  /// \brief Set the vectorize width for the next loop pushed.
148  void setVectorizeWidth(unsigned W) { StagedAttrs.VectorizeWidth = W; }
149 
150  /// \brief Set the interleave count for the next loop pushed.
151  void setInterleaveCount(unsigned C) { StagedAttrs.InterleaveCount = C; }
152 
153  /// \brief Set the unroll count for the next loop pushed.
154  void setUnrollCount(unsigned C) { StagedAttrs.UnrollCount = C; }
155 
156 private:
157  /// \brief Returns true if there is LoopInfo on the stack.
158  bool hasInfo() const { return !Active.empty(); }
159  /// \brief Return the LoopInfo for the current loop. HasInfo should be called
160  /// first to ensure LoopInfo is present.
161  const LoopInfo &getInfo() const { return Active.back(); }
162  /// \brief The set of attributes that will be applied to the next pushed loop.
163  LoopAttributes StagedAttrs;
164  /// \brief Stack of active loops.
166 };
167 
168 } // end namespace CodeGen
169 } // end namespace clang
170 
171 #endif
void setUnrollCount(unsigned C)
Set the unroll count for the next loop pushed.
Definition: CGLoopInfo.h:154
void push(llvm::BasicBlock *Header, llvm::DebugLoc Location=llvm::DebugLoc())
Begin a new structured loop.
Attributes that may be specified on loops.
Definition: CGLoopInfo.h:37
Information used when generating a structured loop.
Definition: CGLoopInfo.h:67
LoopAttributes(bool IsParallel=false)
Definition: CGLoopInfo.cpp:102
LVEnableState UnrollEnable
Value for llvm.loop.unroll.* metadata (enable, disable, or full).
Definition: CGLoopInfo.h:51
llvm::BasicBlock * getHeader() const
Get the header block of this loop.
Definition: CGLoopInfo.h:77
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:92
LineState State
unsigned InterleaveCount
Value for llvm.loop.interleave.count metadata.
Definition: CGLoopInfo.h:57
LVEnableState VectorizeEnable
Value for llvm.loop.vectorize.enable metadata.
Definition: CGLoopInfo.h:48
void pop()
End the current loop.
Definition: CGLoopInfo.cpp:272
void setVectorizeWidth(unsigned W)
Set the vectorize width for the next loop pushed.
Definition: CGLoopInfo.h:148
detail::InMemoryDirectory::const_iterator I
llvm::MDNode * getLoopID() const
Get the loop id metadata for this loop.
Definition: CGLoopInfo.h:74
friend class ASTContext
Definition: Type.h:4178
bool IsParallel
Generate llvm.loop.parallel metadata for loads and stores.
Definition: CGLoopInfo.h:42
bool getCurLoopParallel() const
Return true if the top loop is parallel.
Definition: CGLoopInfo.h:119
void setInterleaveCount(unsigned C)
Set the interleave count for the next loop pushed.
Definition: CGLoopInfo.h:151
unsigned UnrollCount
llvm.unroll.
Definition: CGLoopInfo.h:60
void setParallel(bool Enable=true)
Set the next pushed loop as parallel.
Definition: CGLoopInfo.h:128
LVEnableState DistributeEnable
Value for llvm.loop.distribute.enable metadata.
Definition: CGLoopInfo.h:63
void setDistributeState(bool Enable=true)
Set the next pushed loop as a distribution candidate.
Definition: CGLoopInfo.h:137
LoopInfo(llvm::BasicBlock *Header, const LoopAttributes &Attrs, llvm::DebugLoc Location)
Construct a new LoopInfo for the loop with entry Header.
Definition: CGLoopInfo.cpp:117
A stack of loop information corresponding to loop nesting levels.
Definition: CGLoopInfo.h:94
LVEnableState
State of loop vectorization or unrolling.
Definition: CGLoopInfo.h:45
void InsertHelper(llvm::Instruction *I) const
Function called by the CodeGenFunction when an instruction is created.
Definition: CGLoopInfo.cpp:277
const LoopAttributes & getAttributes() const
Get the set of attributes active for this loop.
Definition: CGLoopInfo.h:80
void setUnrollState(const LoopAttributes::LVEnableState &State)
Set the next pushed loop unroll state.
Definition: CGLoopInfo.h:143
void setVectorizeEnable(bool Enable=true)
Set the next pushed loop 'vectorize.enable'.
Definition: CGLoopInfo.h:131
unsigned VectorizeWidth
Value for llvm.loop.vectorize.width metadata.
Definition: CGLoopInfo.h:54
llvm::MDNode * getCurLoopID() const
Return the top loop id metadata.
Definition: CGLoopInfo.h:116