| 1 | //===- PostOrderCFGView.cpp - Post order view of CFG blocks ---------------===// |
|---|---|
| 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(n: cfg->getNumBlockIDs()); |
| 23 | CFGBlockSet BSet(cfg); |
| 24 | |
| 25 | for (po_iterator I = po_iterator::begin(G: cfg, S&: BSet), |
| 26 | E = po_iterator::end(G: cfg, S&: BSet); I != E; ++I) { |
| 27 | BlockOrder[*I] = Blocks.size() + 1; |
| 28 | Blocks.push_back(x: *I); |
| 29 | } |
| 30 | } |
| 31 | |
| 32 | std::unique_ptr<PostOrderCFGView> |
| 33 | PostOrderCFGView::create(AnalysisDeclContext &ctx) { |
| 34 | const CFG *cfg = ctx.getCFG(); |
| 35 | if (!cfg) |
| 36 | return nullptr; |
| 37 | return std::make_unique<PostOrderCFGView>(args&: cfg); |
| 38 | } |
| 39 | |
| 40 | const void *PostOrderCFGView::getTag() { static int x; return &x; } |
| 41 | |
| 42 | bool PostOrderCFGView::BlockOrderCompare::operator()(const CFGBlock *b1, |
| 43 | const CFGBlock *b2) const { |
| 44 | PostOrderCFGView::BlockOrderTy::const_iterator b1It = POV.BlockOrder.find(Val: b1); |
| 45 | PostOrderCFGView::BlockOrderTy::const_iterator b2It = POV.BlockOrder.find(Val: b2); |
| 46 | |
| 47 | unsigned b1V = (b1It == POV.BlockOrder.end()) ? 0 : b1It->second; |
| 48 | unsigned b2V = (b2It == POV.BlockOrder.end()) ? 0 : b2It->second; |
| 49 | return b1V > b2V; |
| 50 | } |
| 51 |