LLVM  10.0.0svn
SpeculateAnalyses.h
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1 //===-- SpeculateAnalyses.h --*- 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 // \file
9 /// Contains the Analyses and Result Interpretation to select likely functions
10 /// to Speculatively compile before they are called. [Purely Experimentation]
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_EXECUTIONENGINE_ORC_SPECULATEANALYSES_H
14 #define LLVM_EXECUTIONENGINE_ORC_SPECULATEANALYSES_H
15 
19 
20 #include <vector>
21 
22 namespace llvm {
23 
24 namespace orc {
25 
26 // Provides common code.
28 protected:
29  void findCalles(const BasicBlock *, DenseSet<StringRef> &);
30  bool isStraightLine(const Function &F);
31 
32 public:
34 };
35 
36 // Direct calls in high frequency basic blocks are extracted.
38  size_t numBBToGet(size_t);
39 
40 public:
41  // Find likely next executables based on IR Block Frequency
42  ResultTy operator()(Function &F);
43 };
44 
45 // This Query generates a sequence of basic blocks which follows the order of
46 // execution.
47 // A handful of BB with higher block frequencies are taken, then path to entry
48 // and end BB are discovered by traversing up & down the CFG.
50  struct WalkDirection {
51  bool Upward = true, Downward = true;
52  // the block associated contain a call
53  bool CallerBlock = false;
54  };
55 
56 public:
59  using BackEdgesInfoTy =
61  using BlockFreqInfoTy =
63 
64 private:
65  std::size_t getHottestBlocks(std::size_t TotalBlocks);
66  BlockListTy rearrangeBB(const Function &, const BlockListTy &);
67  BlockListTy queryCFG(Function &, const BlockListTy &);
68  void traverseToEntryBlock(const BasicBlock *, const BlockListTy &,
69  const BackEdgesInfoTy &,
70  const BranchProbabilityInfo *,
72  void traverseToExitBlock(const BasicBlock *, const BlockListTy &,
73  const BackEdgesInfoTy &,
74  const BranchProbabilityInfo *,
76 
77 public:
78  ResultTy operator()(Function &F);
79 };
80 
81 } // namespace orc
82 } // namespace llvm
83 
84 #endif // LLVM_EXECUTIONENGINE_ORC_SPECULATEANALYSES_H
This class represents lattice values for constants.
Definition: AllocatorList.h:23
Implements a dense probed hash-table based set.
Definition: DenseSet.h:249
F(f)
void findCalles(const BasicBlock *, DenseSet< StringRef > &)
bool isStraightLine(const Function &F)
LLVM Basic Block Representation.
Definition: BasicBlock.h:57
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:837
Analysis providing branch probability information.