clang  8.0.0
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/SmallVector.h"
20 #include "llvm/IR/DebugLoc.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 /// Attributes that may be specified on loops.
37  explicit LoopAttributes(bool IsParallel = false);
38  void clear();
39 
40  /// Generate llvm.loop.parallel metadata for loads and stores.
41  bool IsParallel;
42 
43  /// State of loop vectorization or unrolling.
44  enum LVEnableState { Unspecified, Enable, Disable, Full };
45 
46  /// Value for llvm.loop.vectorize.enable metadata.
48 
49  /// Value for llvm.loop.unroll.* metadata (enable, disable, or full).
51 
52  /// Value for llvm.loop.unroll_and_jam.* metadata (enable, disable, or full).
54 
55  /// Value for llvm.loop.vectorize.width metadata.
56  unsigned VectorizeWidth;
57 
58  /// Value for llvm.loop.interleave.count metadata.
59  unsigned InterleaveCount;
60 
61  /// llvm.unroll.
62  unsigned UnrollCount;
63 
64  /// llvm.unroll.
66 
67  /// Value for llvm.loop.distribute.enable metadata.
69 
70  /// Value for llvm.loop.pipeline.disable metadata.
72 
73  /// Value for llvm.loop.pipeline.iicount metadata.
75 };
76 
77 /// Information used when generating a structured loop.
78 class LoopInfo {
79 public:
80  /// Construct a new LoopInfo for the loop with entry Header.
81  LoopInfo(llvm::BasicBlock *Header, const LoopAttributes &Attrs,
82  const llvm::DebugLoc &StartLoc, const llvm::DebugLoc &EndLoc);
83 
84  /// Get the loop id metadata for this loop.
85  llvm::MDNode *getLoopID() const { return LoopID; }
86 
87  /// Get the header block of this loop.
88  llvm::BasicBlock *getHeader() const { return Header; }
89 
90  /// Get the set of attributes active for this loop.
91  const LoopAttributes &getAttributes() const { return Attrs; }
92 
93  /// Return this loop's access group or nullptr if it does not have one.
94  llvm::MDNode *getAccessGroup() const { return AccGroup; }
95 
96 private:
97  /// Loop ID metadata.
98  llvm::MDNode *LoopID;
99  /// Header block of this loop.
100  llvm::BasicBlock *Header;
101  /// The attributes for this loop.
102  LoopAttributes Attrs;
103  /// The access group for memory accesses parallel to this loop.
104  llvm::MDNode *AccGroup = nullptr;
105 };
106 
107 /// A stack of loop information corresponding to loop nesting levels.
108 /// This stack can be used to prepare attributes which are applied when a loop
109 /// is emitted.
111  LoopInfoStack(const LoopInfoStack &) = delete;
112  void operator=(const LoopInfoStack &) = delete;
113 
114 public:
116 
117  /// Begin a new structured loop. The set of staged attributes will be
118  /// applied to the loop and then cleared.
119  void push(llvm::BasicBlock *Header, const llvm::DebugLoc &StartLoc,
120  const llvm::DebugLoc &EndLoc);
121 
122  /// Begin a new structured loop. Stage attributes from the Attrs list.
123  /// The staged attributes are applied to the loop and then cleared.
124  void push(llvm::BasicBlock *Header, clang::ASTContext &Ctx,
125  llvm::ArrayRef<const Attr *> Attrs, const llvm::DebugLoc &StartLoc,
126  const llvm::DebugLoc &EndLoc);
127 
128  /// End the current loop.
129  void pop();
130 
131  /// Return the top loop id metadata.
132  llvm::MDNode *getCurLoopID() const { return getInfo().getLoopID(); }
133 
134  /// Return true if the top loop is parallel.
135  bool getCurLoopParallel() const {
136  return hasInfo() ? getInfo().getAttributes().IsParallel : false;
137  }
138 
139  /// Function called by the CodeGenFunction when an instruction is
140  /// created.
141  void InsertHelper(llvm::Instruction *I) const;
142 
143  /// Set the next pushed loop as parallel.
144  void setParallel(bool Enable = true) { StagedAttrs.IsParallel = Enable; }
145 
146  /// Set the next pushed loop 'vectorize.enable'
147  void setVectorizeEnable(bool Enable = true) {
148  StagedAttrs.VectorizeEnable =
149  Enable ? LoopAttributes::Enable : LoopAttributes::Disable;
150  }
151 
152  /// Set the next pushed loop as a distribution candidate.
153  void setDistributeState(bool Enable = true) {
154  StagedAttrs.DistributeEnable =
155  Enable ? LoopAttributes::Enable : LoopAttributes::Disable;
156  }
157 
158  /// Set the next pushed loop unroll state.
160  StagedAttrs.UnrollEnable = State;
161  }
162 
163  /// Set the next pushed loop unroll_and_jam state.
165  StagedAttrs.UnrollAndJamEnable = State;
166  }
167 
168  /// Set the vectorize width for the next loop pushed.
169  void setVectorizeWidth(unsigned W) { StagedAttrs.VectorizeWidth = W; }
170 
171  /// Set the interleave count for the next loop pushed.
172  void setInterleaveCount(unsigned C) { StagedAttrs.InterleaveCount = C; }
173 
174  /// Set the unroll count for the next loop pushed.
175  void setUnrollCount(unsigned C) { StagedAttrs.UnrollCount = C; }
176 
177  /// \brief Set the unroll count for the next loop pushed.
178  void setUnrollAndJamCount(unsigned C) { StagedAttrs.UnrollAndJamCount = C; }
179 
180  /// Set the pipeline disabled state.
181  void setPipelineDisabled(bool S) { StagedAttrs.PipelineDisabled = S; }
182 
183  /// Set the pipeline initiation interval.
184  void setPipelineInitiationInterval(unsigned C) {
185  StagedAttrs.PipelineInitiationInterval = C;
186  }
187 
188 private:
189  /// Returns true if there is LoopInfo on the stack.
190  bool hasInfo() const { return !Active.empty(); }
191  /// Return the LoopInfo for the current loop. HasInfo should be called
192  /// first to ensure LoopInfo is present.
193  const LoopInfo &getInfo() const { return Active.back(); }
194  /// The set of attributes that will be applied to the next pushed loop.
195  LoopAttributes StagedAttrs;
196  /// Stack of active loops.
198 };
199 
200 } // end namespace CodeGen
201 } // end namespace clang
202 
203 #endif
void setUnrollCount(unsigned C)
Set the unroll count for the next loop pushed.
Definition: CGLoopInfo.h:175
DominatorTree GraphTraits specialization so the DominatorTree can be iterable by generic graph iterat...
Definition: Dominators.h:30
Attributes that may be specified on loops.
Definition: CGLoopInfo.h:36
unsigned UnrollAndJamCount
llvm.unroll.
Definition: CGLoopInfo.h:65
Information used when generating a structured loop.
Definition: CGLoopInfo.h:78
virtual void clear()
LVEnableState UnrollEnable
Value for llvm.loop.unroll.* metadata (enable, disable, or full).
Definition: CGLoopInfo.h:50
unsigned PipelineInitiationInterval
Value for llvm.loop.pipeline.iicount metadata.
Definition: CGLoopInfo.h:74
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:155
LineState State
unsigned InterleaveCount
Value for llvm.loop.interleave.count metadata.
Definition: CGLoopInfo.h:59
void setUnrollAndJamCount(unsigned C)
Set the unroll count for the next loop pushed.
Definition: CGLoopInfo.h:178
LVEnableState VectorizeEnable
Value for llvm.loop.vectorize.enable metadata.
Definition: CGLoopInfo.h:47
void setVectorizeWidth(unsigned W)
Set the vectorize width for the next loop pushed.
Definition: CGLoopInfo.h:169
LVEnableState UnrollAndJamEnable
Value for llvm.loop.unroll_and_jam.* metadata (enable, disable, or full).
Definition: CGLoopInfo.h:53
bool IsParallel
Generate llvm.loop.parallel metadata for loads and stores.
Definition: CGLoopInfo.h:41
void setInterleaveCount(unsigned C)
Set the interleave count for the next loop pushed.
Definition: CGLoopInfo.h:172
unsigned UnrollCount
llvm.unroll.
Definition: CGLoopInfo.h:62
void setParallel(bool Enable=true)
Set the next pushed loop as parallel.
Definition: CGLoopInfo.h:144
LVEnableState DistributeEnable
Value for llvm.loop.distribute.enable metadata.
Definition: CGLoopInfo.h:68
llvm::MDNode * getLoopID() const
Get the loop id metadata for this loop.
Definition: CGLoopInfo.h:85
llvm::MDNode * getCurLoopID() const
Return the top loop id metadata.
Definition: CGLoopInfo.h:132
void setDistributeState(bool Enable=true)
Set the next pushed loop as a distribution candidate.
Definition: CGLoopInfo.h:153
llvm::MDNode * getAccessGroup() const
Return this loop&#39;s access group or nullptr if it does not have one.
Definition: CGLoopInfo.h:94
Dataflow Directional Tag Classes.
bool PipelineDisabled
Value for llvm.loop.pipeline.disable metadata.
Definition: CGLoopInfo.h:71
static const TypeInfo & getInfo(unsigned id)
Definition: Types.cpp:34
A stack of loop information corresponding to loop nesting levels.
Definition: CGLoopInfo.h:110
bool getCurLoopParallel() const
Return true if the top loop is parallel.
Definition: CGLoopInfo.h:135
LVEnableState
State of loop vectorization or unrolling.
Definition: CGLoopInfo.h:44
void setUnrollState(const LoopAttributes::LVEnableState &State)
Set the next pushed loop unroll state.
Definition: CGLoopInfo.h:159
void setUnrollAndJamState(const LoopAttributes::LVEnableState &State)
Set the next pushed loop unroll_and_jam state.
Definition: CGLoopInfo.h:164
void setVectorizeEnable(bool Enable=true)
Set the next pushed loop &#39;vectorize.enable&#39;.
Definition: CGLoopInfo.h:147
void setPipelineDisabled(bool S)
Set the pipeline disabled state.
Definition: CGLoopInfo.h:181
void setPipelineInitiationInterval(unsigned C)
Set the pipeline initiation interval.
Definition: CGLoopInfo.h:184
unsigned VectorizeWidth
Value for llvm.loop.vectorize.width metadata.
Definition: CGLoopInfo.h:56
llvm::BasicBlock * getHeader() const
Get the header block of this loop.
Definition: CGLoopInfo.h:88
const LoopAttributes & getAttributes() const
Get the set of attributes active for this loop.
Definition: CGLoopInfo.h:91