1 //===- PostDominators.cpp - Post-Dominator Calculation --------------------===//
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 file implements the post-dominator construction algorithms.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/Analysis/PostDominators.h"
15 #include "llvm/IR/Function.h"
16 #include "llvm/IR/PassManager.h"
17 #include "llvm/Pass.h"
18 #include "llvm/Support/raw_ostream.h"
19 
20 using namespace llvm;
21 
22 #define DEBUG_TYPE "postdomtree"
23 
24 template class llvm::DominatorTreeBase<BasicBlock, true>; // PostDomTreeBase
25 
26 //===----------------------------------------------------------------------===//
27 //  PostDominatorTree Implementation
28 //===----------------------------------------------------------------------===//
29 
30 char PostDominatorTreeWrapperPass::ID = 0;
31 
32 INITIALIZE_PASS(PostDominatorTreeWrapperPass, "postdomtree",
33                 "Post-Dominator Tree Construction", true, true)
34 
35 bool PostDominatorTree::invalidate(Function &F, const PreservedAnalyses &PA,
36                                    FunctionAnalysisManager::Invalidator &) {
37   // Check whether the analysis, all analyses on functions, or the function's
38   // CFG have been preserved.
39   auto PAC = PA.getChecker<PostDominatorTreeAnalysis>();
40   return !(PAC.preserved() || PAC.preservedSet<AllAnalysesOn<Function>>() ||
41            PAC.preservedSet<CFGAnalyses>());
42 }
43 
44 bool PostDominatorTreeWrapperPass::runOnFunction(Function &F) {
45   DT.recalculate(F);
46   return false;
47 }
48 
49 void PostDominatorTreeWrapperPass::print(raw_ostream &OS, const Module *) const {
50   DT.print(OS);
51 }
52 
53 FunctionPass* llvm::createPostDomTree() {
54   return new PostDominatorTreeWrapperPass();
55 }
56 
57 AnalysisKey PostDominatorTreeAnalysis::Key;
58 
59 PostDominatorTree PostDominatorTreeAnalysis::run(Function &F,
60                                                  FunctionAnalysisManager &) {
61   PostDominatorTree PDT;
62   PDT.recalculate(F);
63   return PDT;
64 }
65 
66 PostDominatorTreePrinterPass::PostDominatorTreePrinterPass(raw_ostream &OS)
67   : OS(OS) {}
68 
69 PreservedAnalyses
70 PostDominatorTreePrinterPass::run(Function &F, FunctionAnalysisManager &AM) {
71   OS << "PostDominatorTree for function: " << F.getName() << "\n";
72   AM.getResult<PostDominatorTreeAnalysis>(F).print(OS);
73 
74   return PreservedAnalyses::all();
75 }
76