C++ Function::getEntryBlock方法代码示例

void AstBackEnd::runOnFunction(llvm::Function& fn)
{
	grapher.reset(new AstGrapher);
	
	// Before doing anything, create statements for blocks in reverse post-order. This ensures that values exist
	// before they are used. (Post-order would try to use statements before they were created.)
	for (BasicBlock* block : ReversePostOrderTraversal<BasicBlock*>(&fn.getEntryBlock()))
	{
		grapher->createRegion(*block, *output->basicBlockToStatement(*block));
	}
	
	// Identify loops, then visit basic blocks in post-order. If the basic block if the head
	// of a cyclic region, process the loop. Otherwise, if the basic block is the start of a single-entry-single-exit
	// region, process that region.
	
	auto& domTreeWrapper = getAnalysis<DominatorTreeWrapperPass>(fn);
	domTree = &domTreeWrapper.getDomTree();
	postDomTree->recalculate(fn);
	RootedPostDominatorTree::treeFromIncompleteTree(fn, postDomTree);
	
	// Traverse graph in post-order. Try to detect regions with the post-dominator tree.
	// Cycles are only considered once.
	for (BasicBlock* entry : post_order(&fn.getEntryBlock()))
	{
		BasicBlock* postDominator = entry;
		while (postDominator != nullptr)
		{
			AstGraphNode* graphNode = grapher->getGraphNodeFromEntry(postDominator);
			BasicBlock* exit = graphNode->hasExit()
				? graphNode->getExit()
				: postDominatorOf(*postDomTree, *postDominator);
			
			RegionType region = isRegion(*entry, exit);
			if (region == Acyclic)
			{
				runOnRegion(fn, *entry, exit);
			}
			else if (region == Cyclic)
			{
				runOnLoop(fn, *entry, exit);
			}
			
			if (!domTree->dominates(entry, exit))
			{
				break;
			}
			postDominator = exit;
		}
	}
	
	Statement* bodyStatement = grapher->getGraphNodeFromEntry(&fn.getEntryBlock())->node;
	output->setBody(bodyStatement);
}

bool IndependentBlocks::runOnFunction(llvm::Function &F) {

  bool Changed = false;

  RI = &getAnalysis<RegionInfoPass>().getRegionInfo();
  LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
  SD = &getAnalysis<ScopDetection>();
  SE = &getAnalysis<ScalarEvolution>();

  AllocaBlock = &F.getEntryBlock();

  DEBUG(dbgs() << "Run IndepBlock on " << F.getName() << '\n');

  for (const Region *R : *SD) {
    Changed |= createIndependentBlocks(R);
    Changed |= eliminateDeadCode(R);
    // This may change the RegionTree.
    if (!DisableIntraScopScalarToArray || !PollyModelPHINodes)
      Changed |= splitExitBlock(const_cast<Region *>(R));
  }

  DEBUG(dbgs() << "Before Scalar to Array------->\n");
  DEBUG(F.dump());

  if (!DisableIntraScopScalarToArray || !PollyModelPHINodes)
    for (const Region *R : *SD)
      Changed |= translateScalarToArray(R);

  DEBUG(dbgs() << "After Independent Blocks------------->\n");
  DEBUG(F.dump());

  verifyAnalysis();

  return Changed;
}

std::vector<llvm::BasicBlock*> BasicBlockSorter::sortBasicBlocks(llvm::Function &function)
{
    std::vector<llvm::BasicBlock*> ret;
    std::set<llvm::BasicBlock*> visited;

    llvm::BasicBlock &entryBlock = function.getEntryBlock();

    visitBasicBlock(ret, visited, &entryBlock);

    return ret;
}