1 //===- MachineDomTreeUpdater.cpp -----------------------------------------===//
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 //
9 // This file implements the MachineDomTreeUpdater class, which provides a
10 // uniform way to update dominator tree related data structures.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "llvm/CodeGen/MachineDomTreeUpdater.h"
15 #include "llvm/Analysis/GenericDomTreeUpdaterImpl.h"
16 #include "llvm/CodeGen/MachinePostDominators.h"
17 #include "llvm/Support/Compiler.h"
18
19 namespace llvm {
20
21 template class LLVM_EXPORT_TEMPLATE GenericDomTreeUpdater<
22 MachineDomTreeUpdater, MachineDominatorTree, MachinePostDominatorTree>;
23
24 template LLVM_EXPORT_TEMPLATE void
25 GenericDomTreeUpdater<MachineDomTreeUpdater, MachineDominatorTree,
26 MachinePostDominatorTree>::recalculate(MachineFunction
27 &MF);
28
29 template LLVM_EXPORT_TEMPLATE void GenericDomTreeUpdater<
30 MachineDomTreeUpdater, MachineDominatorTree,
31 MachinePostDominatorTree>::applyUpdatesImpl</*IsForward=*/true>();
32 template LLVM_EXPORT_TEMPLATE void GenericDomTreeUpdater<
33 MachineDomTreeUpdater, MachineDominatorTree,
34 MachinePostDominatorTree>::applyUpdatesImpl</*IsForward=*/false>();
35
forceFlushDeletedBB()36 bool MachineDomTreeUpdater::forceFlushDeletedBB() {
37 if (DeletedBBs.empty())
38 return false;
39
40 for (auto *BB : DeletedBBs) {
41 eraseDelBBNode(BB);
42 BB->eraseFromParent();
43 }
44 DeletedBBs.clear();
45 return true;
46 }
47
48 // The DT and PDT require the nodes related to updates
49 // are not deleted when update functions are called.
50 // So MachineBasicBlock deletions must be pended when the
51 // UpdateStrategy is Lazy. When the UpdateStrategy is
52 // Eager, the MachineBasicBlock will be deleted immediately.
deleteBB(MachineBasicBlock * DelBB)53 void MachineDomTreeUpdater::deleteBB(MachineBasicBlock *DelBB) {
54 validateDeleteBB(DelBB);
55 if (Strategy == UpdateStrategy::Lazy) {
56 DeletedBBs.insert(DelBB);
57 return;
58 }
59
60 eraseDelBBNode(DelBB);
61 DelBB->eraseFromParent();
62 }
63
validateDeleteBB(MachineBasicBlock * DelBB)64 void MachineDomTreeUpdater::validateDeleteBB(MachineBasicBlock *DelBB) {
65 assert(DelBB && "Invalid push_back of nullptr DelBB.");
66 assert(DelBB->pred_empty() && "DelBB has one or more predecessors.");
67 }
68
69 } // namespace llvm
70