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1 //===- LoopInfo.cpp - Natural Loop Calculator -----------------------------===//
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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2 //
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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3 // The LLVM Compiler Infrastructure
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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4 //
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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5 // This file is distributed under the University of Illinois Open Source
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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6 // License. See LICENSE.TXT for details.
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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7 //
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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8 //===----------------------------------------------------------------------===//
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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9 //
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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10 // This file defines the LoopInfo class that is used to identify natural loops
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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11 // and determine the loop depth of various nodes of the CFG. Note that the
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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12 // loops identified may actually be several natural loops that share the same
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13 // header node... not just a single natural loop.
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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14 //
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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15 //===----------------------------------------------------------------------===//
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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16
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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17 #include "llvm/Analysis/LoopInfo.h"
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18 #include "llvm/ADT/DepthFirstIterator.h"
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121
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19 #include "llvm/ADT/ScopeExit.h"
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20 #include "llvm/ADT/SmallPtrSet.h"
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21 #include "llvm/Analysis/LoopInfoImpl.h"
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22 #include "llvm/Analysis/LoopIterator.h"
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23 #include "llvm/Analysis/ValueTracking.h"
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77
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24 #include "llvm/IR/CFG.h"
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25 #include "llvm/IR/Constants.h"
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120
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26 #include "llvm/IR/DebugLoc.h"
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77
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27 #include "llvm/IR/Dominators.h"
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28 #include "llvm/IR/Instructions.h"
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83
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29 #include "llvm/IR/LLVMContext.h"
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30 #include "llvm/IR/Metadata.h"
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83
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31 #include "llvm/IR/PassManager.h"
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32 #include "llvm/Support/CommandLine.h"
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33 #include "llvm/Support/Debug.h"
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95
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34 #include "llvm/Support/raw_ostream.h"
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35 #include <algorithm>
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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36 using namespace llvm;
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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37
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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38 // Explicitly instantiate methods in LoopInfoImpl.h for IR-level Loops.
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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39 template class llvm::LoopBase<BasicBlock, Loop>;
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40 template class llvm::LoopInfoBase<BasicBlock, Loop>;
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41
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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42 // Always verify loopinfo if expensive checking is enabled.
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120
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43 #ifdef EXPENSIVE_CHECKS
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121
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44 bool llvm::VerifyLoopInfo = true;
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45 #else
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121
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46 bool llvm::VerifyLoopInfo = false;
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47 #endif
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121
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48 static cl::opt<bool, true>
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49 VerifyLoopInfoX("verify-loop-info", cl::location(VerifyLoopInfo),
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134
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50 cl::Hidden, cl::desc("Verify loop info (time consuming)"));
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51
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52 //===----------------------------------------------------------------------===//
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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53 // Loop implementation
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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54 //
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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55
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95
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56 bool Loop::isLoopInvariant(const Value *V) const {
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57 if (const Instruction *I = dyn_cast<Instruction>(V))
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58 return !contains(I);
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121
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59 return true; // All non-instructions are loop invariant
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60 }
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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61
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95
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62 bool Loop::hasLoopInvariantOperands(const Instruction *I) const {
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63 return all_of(I->operands(), [this](Value *V) { return isLoopInvariant(V); });
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64 }
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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65
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66 bool Loop::makeLoopInvariant(Value *V, bool &Changed,
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67 Instruction *InsertPt) const {
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68 if (Instruction *I = dyn_cast<Instruction>(V))
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69 return makeLoopInvariant(I, Changed, InsertPt);
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121
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70 return true; // All non-instructions are loop-invariant.
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71 }
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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72
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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73 bool Loop::makeLoopInvariant(Instruction *I, bool &Changed,
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74 Instruction *InsertPt) const {
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75 // Test if the value is already loop-invariant.
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76 if (isLoopInvariant(I))
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77 return true;
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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78 if (!isSafeToSpeculativelyExecute(I))
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79 return false;
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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80 if (I->mayReadFromMemory())
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81 return false;
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95
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82 // EH block instructions are immobile.
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83 if (I->isEHPad())
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84 return false;
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85 // Determine the insertion point, unless one was given.
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86 if (!InsertPt) {
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87 BasicBlock *Preheader = getLoopPreheader();
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88 // Without a preheader, hoisting is not feasible.
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89 if (!Preheader)
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90 return false;
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91 InsertPt = Preheader->getTerminator();
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92 }
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93 // Don't hoist instructions with loop-variant operands.
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100
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94 for (Value *Operand : I->operands())
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95 if (!makeLoopInvariant(Operand, Changed, InsertPt))
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96 return false;
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97
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98 // Hoist.
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99 I->moveBefore(InsertPt);
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100
|
100
|
|
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101 // There is possibility of hoisting this instruction above some arbitrary
|
|
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102 // condition. Any metadata defined on it can be control dependent on this
|
|
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103 // condition. Conservatively strip it here so that we don't give any wrong
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|
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104 // information to the optimizer.
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105 I->dropUnknownNonDebugMetadata();
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106
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107 Changed = true;
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108 return true;
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109 }
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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110
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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111 PHINode *Loop::getCanonicalInductionVariable() const {
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112 BasicBlock *H = getHeader();
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113
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77
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114 BasicBlock *Incoming = nullptr, *Backedge = nullptr;
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115 pred_iterator PI = pred_begin(H);
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121
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116 assert(PI != pred_end(H) && "Loop must have at least one backedge!");
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117 Backedge = *PI++;
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121
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118 if (PI == pred_end(H))
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119 return nullptr; // dead loop
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120 Incoming = *PI++;
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121
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121 if (PI != pred_end(H))
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122 return nullptr; // multiple backedges?
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123
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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124 if (contains(Incoming)) {
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125 if (contains(Backedge))
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77
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126 return nullptr;
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127 std::swap(Incoming, Backedge);
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128 } else if (!contains(Backedge))
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77
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129 return nullptr;
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130
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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131 // Loop over all of the PHI nodes, looking for a canonical indvar.
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132 for (BasicBlock::iterator I = H->begin(); isa<PHINode>(I); ++I) {
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133 PHINode *PN = cast<PHINode>(I);
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134 if (ConstantInt *CI =
|
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121
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135 dyn_cast<ConstantInt>(PN->getIncomingValueForBlock(Incoming)))
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136 if (CI->isZero())
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137 if (Instruction *Inc =
|
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121
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138 dyn_cast<Instruction>(PN->getIncomingValueForBlock(Backedge)))
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|
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139 if (Inc->getOpcode() == Instruction::Add && Inc->getOperand(0) == PN)
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140 if (ConstantInt *CI = dyn_cast<ConstantInt>(Inc->getOperand(1)))
|
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121
|
141 if (CI->isOne())
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142 return PN;
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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143 }
|
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77
|
144 return nullptr;
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145 }
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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146
|
|
120
|
147 // Check that 'BB' doesn't have any uses outside of the 'L'
|
|
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148 static bool isBlockInLCSSAForm(const Loop &L, const BasicBlock &BB,
|
|
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149 DominatorTree &DT) {
|
|
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150 for (const Instruction &I : BB) {
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|
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151 // Tokens can't be used in PHI nodes and live-out tokens prevent loop
|
|
|
152 // optimizations, so for the purposes of considered LCSSA form, we
|
|
|
153 // can ignore them.
|
|
|
154 if (I.getType()->isTokenTy())
|
|
|
155 continue;
|
|
100
|
156
|
|
120
|
157 for (const Use &U : I.uses()) {
|
|
|
158 const Instruction *UI = cast<Instruction>(U.getUser());
|
|
|
159 const BasicBlock *UserBB = UI->getParent();
|
|
|
160 if (const PHINode *P = dyn_cast<PHINode>(UI))
|
|
|
161 UserBB = P->getIncomingBlock(U);
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162
|
|
120
|
163 // Check the current block, as a fast-path, before checking whether
|
|
|
164 // the use is anywhere in the loop. Most values are used in the same
|
|
|
165 // block they are defined in. Also, blocks not reachable from the
|
|
|
166 // entry are special; uses in them don't need to go through PHIs.
|
|
|
167 if (UserBB != &BB && !L.contains(UserBB) &&
|
|
|
168 DT.isReachableFromEntry(UserBB))
|
|
|
169 return false;
|
|
100
|
170 }
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171 }
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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172 return true;
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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|
173 }
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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|
174
|
|
120
|
175 bool Loop::isLCSSAForm(DominatorTree &DT) const {
|
|
|
176 // For each block we check that it doesn't have any uses outside of this loop.
|
|
|
177 return all_of(this->blocks(), [&](const BasicBlock *BB) {
|
|
|
178 return isBlockInLCSSAForm(*this, *BB, DT);
|
|
|
179 });
|
|
|
180 }
|
|
100
|
181
|
|
120
|
182 bool Loop::isRecursivelyLCSSAForm(DominatorTree &DT, const LoopInfo &LI) const {
|
|
121
|
183 // For each block we check that it doesn't have any uses outside of its
|
|
|
184 // innermost loop. This process will transitively guarantee that the current
|
|
|
185 // loop and all of the nested loops are in LCSSA form.
|
|
120
|
186 return all_of(this->blocks(), [&](const BasicBlock *BB) {
|
|
|
187 return isBlockInLCSSAForm(*LI.getLoopFor(BB), *BB, DT);
|
|
100
|
188 });
|
|
|
189 }
|
|
|
190
|
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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|
191 bool Loop::isLoopSimplifyForm() const {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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192 // Normal-form loops have a preheader, a single backedge, and all of their
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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193 // exits have all their predecessors inside the loop.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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194 return getLoopPreheader() && getLoopLatch() && hasDedicatedExits();
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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195 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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changeset
|
196
|
|
100
|
197 // Routines that reform the loop CFG and split edges often fail on indirectbr.
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
198 bool Loop::isSafeToClone() const {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
199 // Return false if any loop blocks contain indirectbrs, or there are any calls
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
200 // to noduplicate functions.
|
|
100
|
201 for (BasicBlock *BB : this->blocks()) {
|
|
|
202 if (isa<IndirectBrInst>(BB->getTerminator()))
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
203 return false;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
204
|
|
120
|
205 for (Instruction &I : *BB)
|
|
|
206 if (auto CS = CallSite(&I))
|
|
|
207 if (CS.cannotDuplicate())
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
208 return false;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
209 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
210 return true;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
211 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
212
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
213 MDNode *Loop::getLoopID() const {
|
|
77
|
214 MDNode *LoopID = nullptr;
|
|
121
|
215 if (BasicBlock *Latch = getLoopLatch()) {
|
|
|
216 LoopID = Latch->getTerminator()->getMetadata(LLVMContext::MD_loop);
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
217 } else {
|
|
121
|
218 assert(!getLoopLatch() &&
|
|
|
219 "The loop should have no single latch at this point");
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
220 // Go through each predecessor of the loop header and check the
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
221 // terminator for the metadata.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
222 BasicBlock *H = getHeader();
|
|
100
|
223 for (BasicBlock *BB : this->blocks()) {
|
|
|
224 TerminatorInst *TI = BB->getTerminator();
|
|
77
|
225 MDNode *MD = nullptr;
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
226
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
227 // Check if this terminator branches to the loop header.
|
|
100
|
228 for (BasicBlock *Successor : TI->successors()) {
|
|
|
229 if (Successor == H) {
|
|
120
|
230 MD = TI->getMetadata(LLVMContext::MD_loop);
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
231 break;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
232 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
233 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
234 if (!MD)
|
|
77
|
235 return nullptr;
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
236
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
237 if (!LoopID)
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
238 LoopID = MD;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
239 else if (MD != LoopID)
|
|
77
|
240 return nullptr;
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
241 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
242 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
243 if (!LoopID || LoopID->getNumOperands() == 0 ||
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
244 LoopID->getOperand(0) != LoopID)
|
|
77
|
245 return nullptr;
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
246 return LoopID;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
247 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
248
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
249 void Loop::setLoopID(MDNode *LoopID) const {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
250 assert(LoopID && "Loop ID should not be null");
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
251 assert(LoopID->getNumOperands() > 0 && "Loop ID needs at least one operand");
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
252 assert(LoopID->getOperand(0) == LoopID && "Loop ID should refer to itself");
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
253
|
|
121
|
254 if (BasicBlock *Latch = getLoopLatch()) {
|
|
|
255 Latch->getTerminator()->setMetadata(LLVMContext::MD_loop, LoopID);
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
256 return;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
257 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
258
|
|
121
|
259 assert(!getLoopLatch() &&
|
|
|
260 "The loop should have no single latch at this point");
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
261 BasicBlock *H = getHeader();
|
|
100
|
262 for (BasicBlock *BB : this->blocks()) {
|
|
|
263 TerminatorInst *TI = BB->getTerminator();
|
|
|
264 for (BasicBlock *Successor : TI->successors()) {
|
|
|
265 if (Successor == H)
|
|
120
|
266 TI->setMetadata(LLVMContext::MD_loop, LoopID);
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
267 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
268 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
269 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
270
|
|
121
|
271 void Loop::setLoopAlreadyUnrolled() {
|
|
|
272 MDNode *LoopID = getLoopID();
|
|
|
273 // First remove any existing loop unrolling metadata.
|
|
|
274 SmallVector<Metadata *, 4> MDs;
|
|
|
275 // Reserve first location for self reference to the LoopID metadata node.
|
|
|
276 MDs.push_back(nullptr);
|
|
|
277
|
|
|
278 if (LoopID) {
|
|
|
279 for (unsigned i = 1, ie = LoopID->getNumOperands(); i < ie; ++i) {
|
|
|
280 bool IsUnrollMetadata = false;
|
|
|
281 MDNode *MD = dyn_cast<MDNode>(LoopID->getOperand(i));
|
|
|
282 if (MD) {
|
|
|
283 const MDString *S = dyn_cast<MDString>(MD->getOperand(0));
|
|
|
284 IsUnrollMetadata = S && S->getString().startswith("llvm.loop.unroll.");
|
|
|
285 }
|
|
|
286 if (!IsUnrollMetadata)
|
|
|
287 MDs.push_back(LoopID->getOperand(i));
|
|
|
288 }
|
|
|
289 }
|
|
|
290
|
|
|
291 // Add unroll(disable) metadata to disable future unrolling.
|
|
|
292 LLVMContext &Context = getHeader()->getContext();
|
|
|
293 SmallVector<Metadata *, 1> DisableOperands;
|
|
|
294 DisableOperands.push_back(MDString::get(Context, "llvm.loop.unroll.disable"));
|
|
|
295 MDNode *DisableNode = MDNode::get(Context, DisableOperands);
|
|
|
296 MDs.push_back(DisableNode);
|
|
|
297
|
|
|
298 MDNode *NewLoopID = MDNode::get(Context, MDs);
|
|
|
299 // Set operand 0 to refer to the loop id itself.
|
|
|
300 NewLoopID->replaceOperandWith(0, NewLoopID);
|
|
|
301 setLoopID(NewLoopID);
|
|
|
302 }
|
|
|
303
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
304 bool Loop::isAnnotatedParallel() const {
|
|
100
|
305 MDNode *DesiredLoopIdMetadata = getLoopID();
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
306
|
|
100
|
307 if (!DesiredLoopIdMetadata)
|
|
121
|
308 return false;
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
309
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
310 // The loop branch contains the parallel loop metadata. In order to ensure
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
311 // that any parallel-loop-unaware optimization pass hasn't added loop-carried
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
312 // dependencies (thus converted the loop back to a sequential loop), check
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
313 // that all the memory instructions in the loop contain parallelism metadata
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
314 // that point to the same unique "loop id metadata" the loop branch does.
|
|
100
|
315 for (BasicBlock *BB : this->blocks()) {
|
|
|
316 for (Instruction &I : *BB) {
|
|
|
317 if (!I.mayReadOrWriteMemory())
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
318 continue;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
319
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
320 // The memory instruction can refer to the loop identifier metadata
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
321 // directly or indirectly through another list metadata (in case of
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
322 // nested parallel loops). The loop identifier metadata refers to
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
323 // itself so we can check both cases with the same routine.
|
|
100
|
324 MDNode *LoopIdMD =
|
|
|
325 I.getMetadata(LLVMContext::MD_mem_parallel_loop_access);
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
326
|
|
100
|
327 if (!LoopIdMD)
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
328 return false;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
329
|
|
100
|
330 bool LoopIdMDFound = false;
|
|
|
331 for (const MDOperand &MDOp : LoopIdMD->operands()) {
|
|
|
332 if (MDOp == DesiredLoopIdMetadata) {
|
|
|
333 LoopIdMDFound = true;
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
334 break;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
335 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
336 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
337
|
|
100
|
338 if (!LoopIdMDFound)
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
339 return false;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
340 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
341 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
342 return true;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
343 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
344
|
|
121
|
345 DebugLoc Loop::getStartLoc() const { return getLocRange().getStart(); }
|
|
120
|
346
|
|
|
347 Loop::LocRange Loop::getLocRange() const {
|
|
|
348 // If we have a debug location in the loop ID, then use it.
|
|
|
349 if (MDNode *LoopID = getLoopID()) {
|
|
|
350 DebugLoc Start;
|
|
|
351 // We use the first DebugLoc in the header as the start location of the loop
|
|
|
352 // and if there is a second DebugLoc in the header we use it as end location
|
|
|
353 // of the loop.
|
|
|
354 for (unsigned i = 1, ie = LoopID->getNumOperands(); i < ie; ++i) {
|
|
|
355 if (DILocation *L = dyn_cast<DILocation>(LoopID->getOperand(i))) {
|
|
|
356 if (!Start)
|
|
|
357 Start = DebugLoc(L);
|
|
|
358 else
|
|
|
359 return LocRange(Start, DebugLoc(L));
|
|
|
360 }
|
|
|
361 }
|
|
|
362
|
|
|
363 if (Start)
|
|
|
364 return LocRange(Start);
|
|
|
365 }
|
|
|
366
|
|
|
367 // Try the pre-header first.
|
|
|
368 if (BasicBlock *PHeadBB = getLoopPreheader())
|
|
|
369 if (DebugLoc DL = PHeadBB->getTerminator()->getDebugLoc())
|
|
|
370 return LocRange(DL);
|
|
|
371
|
|
|
372 // If we have no pre-header or there are no instructions with debug
|
|
|
373 // info in it, try the header.
|
|
|
374 if (BasicBlock *HeadBB = getHeader())
|
|
|
375 return LocRange(HeadBB->getTerminator()->getDebugLoc());
|
|
|
376
|
|
|
377 return LocRange();
|
|
|
378 }
|
|
|
379
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
380 bool Loop::hasDedicatedExits() const {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
381 // Each predecessor of each exit block of a normal loop is contained
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
382 // within the loop.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
383 SmallVector<BasicBlock *, 4> ExitBlocks;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
384 getExitBlocks(ExitBlocks);
|
|
100
|
385 for (BasicBlock *BB : ExitBlocks)
|
|
|
386 for (BasicBlock *Predecessor : predecessors(BB))
|
|
|
387 if (!contains(Predecessor))
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
388 return false;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
389 // All the requirements are met.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
390 return true;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
391 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
392
|
|
121
|
393 void Loop::getUniqueExitBlocks(
|
|
|
394 SmallVectorImpl<BasicBlock *> &ExitBlocks) const {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
395 assert(hasDedicatedExits() &&
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
396 "getUniqueExitBlocks assumes the loop has canonical form exits!");
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
397
|
|
100
|
398 SmallVector<BasicBlock *, 32> SwitchExitBlocks;
|
|
|
399 for (BasicBlock *BB : this->blocks()) {
|
|
|
400 SwitchExitBlocks.clear();
|
|
|
401 for (BasicBlock *Successor : successors(BB)) {
|
|
|
402 // If block is inside the loop then it is not an exit block.
|
|
|
403 if (contains(Successor))
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
404 continue;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
405
|
|
100
|
406 pred_iterator PI = pred_begin(Successor);
|
|
|
407 BasicBlock *FirstPred = *PI;
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
408
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
409 // If current basic block is this exit block's first predecessor
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
410 // then only insert exit block in to the output ExitBlocks vector.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
411 // This ensures that same exit block is not inserted twice into
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
412 // ExitBlocks vector.
|
|
100
|
413 if (BB != FirstPred)
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
414 continue;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
415
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
416 // If a terminator has more then two successors, for example SwitchInst,
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
417 // then it is possible that there are multiple edges from current block
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
418 // to one exit block.
|
|
100
|
419 if (std::distance(succ_begin(BB), succ_end(BB)) <= 2) {
|
|
|
420 ExitBlocks.push_back(Successor);
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
421 continue;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
422 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
423
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
424 // In case of multiple edges from current block to exit block, collect
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
425 // only one edge in ExitBlocks. Use switchExitBlocks to keep track of
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
426 // duplicate edges.
|
|
120
|
427 if (!is_contained(SwitchExitBlocks, Successor)) {
|
|
100
|
428 SwitchExitBlocks.push_back(Successor);
|
|
|
429 ExitBlocks.push_back(Successor);
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
430 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
431 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
432 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
433 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
434
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
435 BasicBlock *Loop::getUniqueExitBlock() const {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
436 SmallVector<BasicBlock *, 8> UniqueExitBlocks;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
437 getUniqueExitBlocks(UniqueExitBlocks);
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
438 if (UniqueExitBlocks.size() == 1)
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
439 return UniqueExitBlocks[0];
|
|
77
|
440 return nullptr;
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
441 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
442
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
443 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
|
|
121
|
444 LLVM_DUMP_METHOD void Loop::dump() const { print(dbgs()); }
|
|
120
|
445
|
|
|
446 LLVM_DUMP_METHOD void Loop::dumpVerbose() const {
|
|
121
|
447 print(dbgs(), /*Depth=*/0, /*Verbose=*/true);
|
|
120
|
448 }
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
449 #endif
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
450
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
451 //===----------------------------------------------------------------------===//
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
452 // UnloopUpdater implementation
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
453 //
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
454
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
455 namespace {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
456 /// Find the new parent loop for all blocks within the "unloop" whose last
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
457 /// backedges has just been removed.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
458 class UnloopUpdater {
|
|
120
|
459 Loop &Unloop;
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
460 LoopInfo *LI;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
461
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
462 LoopBlocksDFS DFS;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
463
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
464 // Map unloop's immediate subloops to their nearest reachable parents. Nested
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
465 // loops within these subloops will not change parents. However, an immediate
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
466 // subloop's new parent will be the nearest loop reachable from either its own
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
467 // exits *or* any of its nested loop's exits.
|
|
121
|
468 DenseMap<Loop *, Loop *> SubloopParents;
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
469
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
470 // Flag the presence of an irreducible backedge whose destination is a block
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
471 // directly contained by the original unloop.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
472 bool FoundIB;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
473
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
474 public:
|
|
121
|
475 UnloopUpdater(Loop *UL, LoopInfo *LInfo)
|
|
|
476 : Unloop(*UL), LI(LInfo), DFS(UL), FoundIB(false) {}
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
477
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
478 void updateBlockParents();
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
479
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
480 void removeBlocksFromAncestors();
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
481
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
482 void updateSubloopParents();
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
483
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
484 protected:
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
485 Loop *getNearestLoop(BasicBlock *BB, Loop *BBLoop);
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
486 };
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
487 } // end anonymous namespace
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
488
|
|
100
|
489 /// Update the parent loop for all blocks that are directly contained within the
|
|
|
490 /// original "unloop".
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
491 void UnloopUpdater::updateBlockParents() {
|
|
120
|
492 if (Unloop.getNumBlocks()) {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
493 // Perform a post order CFG traversal of all blocks within this loop,
|
|
121
|
494 // propagating the nearest loop from successors to predecessors.
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
495 LoopBlocksTraversal Traversal(DFS, LI);
|
|
120
|
496 for (BasicBlock *POI : Traversal) {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
497
|
|
120
|
498 Loop *L = LI->getLoopFor(POI);
|
|
|
499 Loop *NL = getNearestLoop(POI, L);
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
500
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
501 if (NL != L) {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
502 // For reducible loops, NL is now an ancestor of Unloop.
|
|
120
|
503 assert((NL != &Unloop && (!NL || NL->contains(&Unloop))) &&
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
504 "uninitialized successor");
|
|
120
|
505 LI->changeLoopFor(POI, NL);
|
|
121
|
506 } else {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
507 // Or the current block is part of a subloop, in which case its parent
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
508 // is unchanged.
|
|
120
|
509 assert((FoundIB || Unloop.contains(L)) && "uninitialized successor");
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
510 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
511 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
512 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
513 // Each irreducible loop within the unloop induces a round of iteration using
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
514 // the DFS result cached by Traversal.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
515 bool Changed = FoundIB;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
516 for (unsigned NIters = 0; Changed; ++NIters) {
|
|
120
|
517 assert(NIters < Unloop.getNumBlocks() && "runaway iterative algorithm");
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
518
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
519 // Iterate over the postorder list of blocks, propagating the nearest loop
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
520 // from successors to predecessors as before.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
521 Changed = false;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
522 for (LoopBlocksDFS::POIterator POI = DFS.beginPostorder(),
|
|
121
|
523 POE = DFS.endPostorder();
|
|
|
524 POI != POE; ++POI) {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
525
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
526 Loop *L = LI->getLoopFor(*POI);
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
527 Loop *NL = getNearestLoop(*POI, L);
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
528 if (NL != L) {
|
|
120
|
529 assert(NL != &Unloop && (!NL || NL->contains(&Unloop)) &&
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
530 "uninitialized successor");
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
531 LI->changeLoopFor(*POI, NL);
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
532 Changed = true;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
533 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
534 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
535 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
536 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
537
|
|
100
|
538 /// Remove unloop's blocks from all ancestors below their new parents.
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
539 void UnloopUpdater::removeBlocksFromAncestors() {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
540 // Remove all unloop's blocks (including those in nested subloops) from
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
541 // ancestors below the new parent loop.
|
|
121
|
542 for (Loop::block_iterator BI = Unloop.block_begin(), BE = Unloop.block_end();
|
|
|
543 BI != BE; ++BI) {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
544 Loop *OuterParent = LI->getLoopFor(*BI);
|
|
120
|
545 if (Unloop.contains(OuterParent)) {
|
|
|
546 while (OuterParent->getParentLoop() != &Unloop)
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
547 OuterParent = OuterParent->getParentLoop();
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
548 OuterParent = SubloopParents[OuterParent];
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
549 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
550 // Remove blocks from former Ancestors except Unloop itself which will be
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
551 // deleted.
|
|
120
|
552 for (Loop *OldParent = Unloop.getParentLoop(); OldParent != OuterParent;
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
553 OldParent = OldParent->getParentLoop()) {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
554 assert(OldParent && "new loop is not an ancestor of the original");
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
555 OldParent->removeBlockFromLoop(*BI);
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
556 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
557 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
558 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
559
|
|
100
|
560 /// Update the parent loop for all subloops directly nested within unloop.
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
561 void UnloopUpdater::updateSubloopParents() {
|
|
120
|
562 while (!Unloop.empty()) {
|
|
|
563 Loop *Subloop = *std::prev(Unloop.end());
|
|
|
564 Unloop.removeChildLoop(std::prev(Unloop.end()));
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
565
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
566 assert(SubloopParents.count(Subloop) && "DFS failed to visit subloop");
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
567 if (Loop *Parent = SubloopParents[Subloop])
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
568 Parent->addChildLoop(Subloop);
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
569 else
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
570 LI->addTopLevelLoop(Subloop);
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
571 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
572 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
573
|
|
100
|
574 /// Return the nearest parent loop among this block's successors. If a successor
|
|
|
575 /// is a subloop header, consider its parent to be the nearest parent of the
|
|
|
576 /// subloop's exits.
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
577 ///
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
578 /// For subloop blocks, simply update SubloopParents and return NULL.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
579 Loop *UnloopUpdater::getNearestLoop(BasicBlock *BB, Loop *BBLoop) {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
580
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
581 // Initially for blocks directly contained by Unloop, NearLoop == Unloop and
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
582 // is considered uninitialized.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
583 Loop *NearLoop = BBLoop;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
584
|
|
77
|
585 Loop *Subloop = nullptr;
|
|
120
|
586 if (NearLoop != &Unloop && Unloop.contains(NearLoop)) {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
587 Subloop = NearLoop;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
588 // Find the subloop ancestor that is directly contained within Unloop.
|
|
120
|
589 while (Subloop->getParentLoop() != &Unloop) {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
590 Subloop = Subloop->getParentLoop();
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
591 assert(Subloop && "subloop is not an ancestor of the original loop");
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
592 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
593 // Get the current nearest parent of the Subloop exits, initially Unloop.
|
|
120
|
594 NearLoop = SubloopParents.insert({Subloop, &Unloop}).first->second;
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
595 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
596
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
597 succ_iterator I = succ_begin(BB), E = succ_end(BB);
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
598 if (I == E) {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
599 assert(!Subloop && "subloop blocks must have a successor");
|
|
77
|
600 NearLoop = nullptr; // unloop blocks may now exit the function.
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
601 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
602 for (; I != E; ++I) {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
603 if (*I == BB)
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
604 continue; // self loops are uninteresting
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
605
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
606 Loop *L = LI->getLoopFor(*I);
|
|
120
|
607 if (L == &Unloop) {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
608 // This successor has not been processed. This path must lead to an
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
609 // irreducible backedge.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
610 assert((FoundIB || !DFS.hasPostorder(*I)) && "should have seen IB");
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
611 FoundIB = true;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
612 }
|
|
120
|
613 if (L != &Unloop && Unloop.contains(L)) {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
614 // Successor is in a subloop.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
615 if (Subloop)
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
616 continue; // Branching within subloops. Ignore it.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
617
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
618 // BB branches from the original into a subloop header.
|
|
120
|
619 assert(L->getParentLoop() == &Unloop && "cannot skip into nested loops");
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
620
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
621 // Get the current nearest parent of the Subloop's exits.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
622 L = SubloopParents[L];
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
623 // L could be Unloop if the only exit was an irreducible backedge.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
624 }
|
|
120
|
625 if (L == &Unloop) {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
626 continue;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
627 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
628 // Handle critical edges from Unloop into a sibling loop.
|
|
120
|
629 if (L && !L->contains(&Unloop)) {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
630 L = L->getParentLoop();
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
631 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
632 // Remember the nearest parent loop among successors or subloop exits.
|
|
120
|
633 if (NearLoop == &Unloop || !NearLoop || NearLoop->contains(L))
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
634 NearLoop = L;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
635 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
636 if (Subloop) {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
637 SubloopParents[Subloop] = NearLoop;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
638 return BBLoop;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
639 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
640 return NearLoop;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
641 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
642
|
|
121
|
643 LoopInfo::LoopInfo(const DomTreeBase<BasicBlock> &DomTree) { analyze(DomTree); }
|
|
|
644
|
|
|
645 bool LoopInfo::invalidate(Function &F, const PreservedAnalyses &PA,
|
|
|
646 FunctionAnalysisManager::Invalidator &) {
|
|
|
647 // Check whether the analysis, all analyses on functions, or the function's
|
|
|
648 // CFG have been preserved.
|
|
|
649 auto PAC = PA.getChecker<LoopAnalysis>();
|
|
|
650 return !(PAC.preserved() || PAC.preservedSet<AllAnalysesOn<Function>>() ||
|
|
|
651 PAC.preservedSet<CFGAnalyses>());
|
|
95
|
652 }
|
|
|
653
|
|
121
|
654 void LoopInfo::erase(Loop *Unloop) {
|
|
|
655 assert(!Unloop->isInvalid() && "Loop has already been erased!");
|
|
|
656
|
|
|
657 auto InvalidateOnExit = make_scope_exit([&]() { destroy(Unloop); });
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
658
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
659 // First handle the special case of no parent loop to simplify the algorithm.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
660 if (!Unloop->getParentLoop()) {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
661 // Since BBLoop had no parent, Unloop blocks are no longer in a loop.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
662 for (Loop::block_iterator I = Unloop->block_begin(),
|
|
83
|
663 E = Unloop->block_end();
|
|
|
664 I != E; ++I) {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
665
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
666 // Don't reparent blocks in subloops.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
667 if (getLoopFor(*I) != Unloop)
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
668 continue;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
669
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
670 // Blocks no longer have a parent but are still referenced by Unloop until
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
671 // the Unloop object is deleted.
|
|
83
|
672 changeLoopFor(*I, nullptr);
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
673 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
674
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
675 // Remove the loop from the top-level LoopInfo object.
|
|
83
|
676 for (iterator I = begin();; ++I) {
|
|
|
677 assert(I != end() && "Couldn't find loop");
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
678 if (*I == Unloop) {
|
|
83
|
679 removeLoop(I);
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
680 break;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
681 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
682 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
683
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
684 // Move all of the subloops to the top-level.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
685 while (!Unloop->empty())
|
|
83
|
686 addTopLevelLoop(Unloop->removeChildLoop(std::prev(Unloop->end())));
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
687
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
688 return;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
689 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
690
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
691 // Update the parent loop for all blocks within the loop. Blocks within
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
692 // subloops will not change parents.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
693 UnloopUpdater Updater(Unloop, this);
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
694 Updater.updateBlockParents();
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
695
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
696 // Remove blocks from former ancestor loops.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
697 Updater.removeBlocksFromAncestors();
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
698
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
699 // Add direct subloops as children in their new parent loop.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
700 Updater.updateSubloopParents();
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
701
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
702 // Remove unloop from its parent loop.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
703 Loop *ParentLoop = Unloop->getParentLoop();
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
704 for (Loop::iterator I = ParentLoop->begin();; ++I) {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
705 assert(I != ParentLoop->end() && "Couldn't find loop");
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
706 if (*I == Unloop) {
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
707 ParentLoop->removeChildLoop(I);
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
708 break;
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
709 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
710 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
711 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
712
|
|
120
|
713 AnalysisKey LoopAnalysis::Key;
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
714
|
|
120
|
715 LoopInfo LoopAnalysis::run(Function &F, FunctionAnalysisManager &AM) {
|
|
83
|
716 // FIXME: Currently we create a LoopInfo from scratch for every function.
|
|
|
717 // This may prove to be too wasteful due to deallocating and re-allocating
|
|
|
718 // memory each time for the underlying map and vector datastructures. At some
|
|
|
719 // point it may prove worthwhile to use a freelist and recycle LoopInfo
|
|
|
720 // objects. I don't want to add that kind of complexity until the scope of
|
|
|
721 // the problem is better understood.
|
|
|
722 LoopInfo LI;
|
|
120
|
723 LI.analyze(AM.getResult<DominatorTreeAnalysis>(F));
|
|
95
|
724 return LI;
|
|
83
|
725 }
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
726
|
|
83
|
727 PreservedAnalyses LoopPrinterPass::run(Function &F,
|
|
120
|
728 FunctionAnalysisManager &AM) {
|
|
|
729 AM.getResult<LoopAnalysis>(F).print(OS);
|
|
83
|
730 return PreservedAnalyses::all();
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
731 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
732
|
|
121
|
733 void llvm::printLoop(Loop &L, raw_ostream &OS, const std::string &Banner) {
|
|
134
|
734
|
|
|
735 if (forcePrintModuleIR()) {
|
|
|
736 // handling -print-module-scope
|
|
|
737 OS << Banner << " (loop: ";
|
|
|
738 L.getHeader()->printAsOperand(OS, false);
|
|
|
739 OS << ")\n";
|
|
|
740
|
|
|
741 // printing whole module
|
|
|
742 OS << *L.getHeader()->getModule();
|
|
|
743 return;
|
|
|
744 }
|
|
|
745
|
|
100
|
746 OS << Banner;
|
|
134
|
747
|
|
|
748 auto *PreHeader = L.getLoopPreheader();
|
|
|
749 if (PreHeader) {
|
|
|
750 OS << "\n; Preheader:";
|
|
|
751 PreHeader->print(OS);
|
|
|
752 OS << "\n; Loop:";
|
|
|
753 }
|
|
|
754
|
|
100
|
755 for (auto *Block : L.blocks())
|
|
|
756 if (Block)
|
|
|
757 Block->print(OS);
|
|
|
758 else
|
|
|
759 OS << "Printing <null> block";
|
|
134
|
760
|
|
|
761 SmallVector<BasicBlock *, 8> ExitBlocks;
|
|
|
762 L.getExitBlocks(ExitBlocks);
|
|
|
763 if (!ExitBlocks.empty()) {
|
|
|
764 OS << "\n; Exit blocks";
|
|
|
765 for (auto *Block : ExitBlocks)
|
|
|
766 if (Block)
|
|
|
767 Block->print(OS);
|
|
|
768 else
|
|
|
769 OS << "Printing <null> block";
|
|
|
770 }
|
|
100
|
771 }
|
|
|
772
|
|
83
|
773 //===----------------------------------------------------------------------===//
|
|
|
774 // LoopInfo implementation
|
|
|
775 //
|
|
|
776
|
|
|
777 char LoopInfoWrapperPass::ID = 0;
|
|
|
778 INITIALIZE_PASS_BEGIN(LoopInfoWrapperPass, "loops", "Natural Loop Information",
|
|
|
779 true, true)
|
|
|
780 INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
|
|
|
781 INITIALIZE_PASS_END(LoopInfoWrapperPass, "loops", "Natural Loop Information",
|
|
|
782 true, true)
|
|
|
783
|
|
|
784 bool LoopInfoWrapperPass::runOnFunction(Function &) {
|
|
|
785 releaseMemory();
|
|
95
|
786 LI.analyze(getAnalysis<DominatorTreeWrapperPass>().getDomTree());
|
|
83
|
787 return false;
|
|
|
788 }
|
|
|
789
|
|
|
790 void LoopInfoWrapperPass::verifyAnalysis() const {
|
|
|
791 // LoopInfoWrapperPass is a FunctionPass, but verifying every loop in the
|
|
|
792 // function each time verifyAnalysis is called is very expensive. The
|
|
|
793 // -verify-loop-info option can enable this. In order to perform some
|
|
|
794 // checking by default, LoopPass has been taught to call verifyLoop manually
|
|
|
795 // during loop pass sequences.
|
|
120
|
796 if (VerifyLoopInfo) {
|
|
|
797 auto &DT = getAnalysis<DominatorTreeWrapperPass>().getDomTree();
|
|
|
798 LI.verify(DT);
|
|
|
799 }
|
|
83
|
800 }
|
|
|
801
|
|
|
802 void LoopInfoWrapperPass::getAnalysisUsage(AnalysisUsage &AU) const {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
803 AU.setPreservesAll();
|
|
77
|
804 AU.addRequired<DominatorTreeWrapperPass>();
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
805 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
806
|
|
83
|
807 void LoopInfoWrapperPass::print(raw_ostream &OS, const Module *) const {
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
808 LI.print(OS);
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
809 }
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
810
|
|
120
|
811 PreservedAnalyses LoopVerifierPass::run(Function &F,
|
|
|
812 FunctionAnalysisManager &AM) {
|
|
|
813 LoopInfo &LI = AM.getResult<LoopAnalysis>(F);
|
|
|
814 auto &DT = AM.getResult<DominatorTreeAnalysis>(F);
|
|
|
815 LI.verify(DT);
|
|
|
816 return PreservedAnalyses::all();
|
|
|
817 }
|
|
|
818
|
0
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
819 //===----------------------------------------------------------------------===//
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
820 // LoopBlocksDFS implementation
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
821 //
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
822
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
parents:
diff
changeset
|
823 /// Traverse the loop blocks and store the DFS result.
|
Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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824 /// Useful for clients that just want the final DFS result and don't need to
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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825 /// visit blocks during the initial traversal.
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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826 void LoopBlocksDFS::perform(LoopInfo *LI) {
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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827 LoopBlocksTraversal Traversal(*this, LI);
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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828 for (LoopBlocksTraversal::POTIterator POI = Traversal.begin(),
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121
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829 POE = Traversal.end();
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830 POI != POE; ++POI)
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831 ;
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Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
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832 }
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