1 //===- LazyBlockFrequencyInfo.cpp - Lazy Block Frequency Analysis ---------===//
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 an alternative analysis pass to BlockFrequencyInfoWrapperPass. The
11 // difference is that with this pass the block frequencies are not computed when
12 // the analysis pass is executed but rather when the BFI results is explicitly
13 // requested by the analysis client.
14 //
15 //===----------------------------------------------------------------------===//
16
17 #include "llvm/Analysis/LazyBlockFrequencyInfo.h"
18 #include "llvm/Analysis/BranchProbabilityInfo.h"
19 #include "llvm/Analysis/LoopInfo.h"
20
21 using namespace llvm;
22
23 #define DEBUG_TYPE "lazy-block-freq"
24
25 INITIALIZE_PASS_BEGIN(LazyBlockFrequencyInfoPass, DEBUG_TYPE,
26 "Lazy Block Frequency Analysis", true, true)
27 INITIALIZE_PASS_DEPENDENCY(BranchProbabilityInfoWrapperPass)
28 INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
29 INITIALIZE_PASS_END(LazyBlockFrequencyInfoPass, DEBUG_TYPE,
30 "Lazy Block Frequency Analysis", true, true)
31
32 char LazyBlockFrequencyInfoPass::ID = 0;
33
LazyBlockFrequencyInfoPass()34 LazyBlockFrequencyInfoPass::LazyBlockFrequencyInfoPass() : FunctionPass(ID) {
35 initializeLazyBlockFrequencyInfoPassPass(*PassRegistry::getPassRegistry());
36 }
37
print(raw_ostream & OS,const Module *) const38 void LazyBlockFrequencyInfoPass::print(raw_ostream &OS, const Module *) const {
39 LBFI.getCalculated().print(OS);
40 }
41
getAnalysisUsage(AnalysisUsage & AU) const42 void LazyBlockFrequencyInfoPass::getAnalysisUsage(AnalysisUsage &AU) const {
43 AU.addRequired<BranchProbabilityInfoWrapperPass>();
44 AU.addRequired<LoopInfoWrapperPass>();
45 AU.setPreservesAll();
46 }
47
releaseMemory()48 void LazyBlockFrequencyInfoPass::releaseMemory() { LBFI.releaseMemory(); }
49
runOnFunction(Function & F)50 bool LazyBlockFrequencyInfoPass::runOnFunction(Function &F) {
51 BranchProbabilityInfo &BPI =
52 getAnalysis<BranchProbabilityInfoWrapperPass>().getBPI();
53 LoopInfo &LI = getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
54 LBFI.setAnalysis(&F, &BPI, &LI);
55 return false;
56 }
57
getLazyBFIAnalysisUsage(AnalysisUsage & AU)58 void LazyBlockFrequencyInfoPass::getLazyBFIAnalysisUsage(AnalysisUsage &AU) {
59 AU.addRequired<BranchProbabilityInfoWrapperPass>();
60 AU.addRequired<LazyBlockFrequencyInfoPass>();
61 AU.addRequired<LoopInfoWrapperPass>();
62 }
63
initializeLazyBFIPassPass(PassRegistry & Registry)64 void llvm::initializeLazyBFIPassPass(PassRegistry &Registry) {
65 INITIALIZE_PASS_DEPENDENCY(BranchProbabilityInfoWrapperPass);
66 INITIALIZE_PASS_DEPENDENCY(LazyBlockFrequencyInfoPass);
67 INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass);
68 }
69