1 | //===- PostOrderCFGView.cpp - Post order view of CFG blocks ---------------===// |
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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 post order view of the blocks in a CFG. |
10 | // |
11 | //===----------------------------------------------------------------------===// |
12 | |
13 | #include "clang/Analysis/Analyses/PostOrderCFGView.h" |
14 | #include "clang/Analysis/AnalysisDeclContext.h" |
15 | #include "clang/Analysis/CFG.h" |
16 | |
17 | using namespace clang; |
18 | |
19 | void PostOrderCFGView::anchor() {} |
20 | |
21 | PostOrderCFGView::PostOrderCFGView(const CFG *cfg) { |
22 | Blocks.reserve(cfg->getNumBlockIDs()); |
23 | CFGBlockSet BSet(cfg); |
24 | |
25 | for (po_iterator I = po_iterator::begin(cfg, BSet), |
26 | E = po_iterator::end(cfg, BSet); I != E; ++I) { |
27 | BlockOrder[*I] = Blocks.size() + 1; |
28 | Blocks.push_back(*I); |
29 | } |
30 | } |
31 | |
32 | PostOrderCFGView *PostOrderCFGView::create(AnalysisDeclContext &ctx) { |
33 | const CFG *cfg = ctx.getCFG(); |
34 | if (!cfg) |
35 | return nullptr; |
36 | return new PostOrderCFGView(cfg); |
37 | } |
38 | |
39 | const void *PostOrderCFGView::getTag() { static int x; return &x; } |
40 | |
41 | bool PostOrderCFGView::BlockOrderCompare::operator()(const CFGBlock *b1, |
42 | const CFGBlock *b2) const { |
43 | PostOrderCFGView::BlockOrderTy::const_iterator b1It = POV.BlockOrder.find(b1); |
44 | PostOrderCFGView::BlockOrderTy::const_iterator b2It = POV.BlockOrder.find(b2); |
45 | |
46 | unsigned b1V = (b1It == POV.BlockOrder.end()) ? 0 : b1It->second; |
47 | unsigned b2V = (b2It == POV.BlockOrder.end()) ? 0 : b2It->second; |
48 | return b1V > b2V; |
49 | } |
50 |