//===- LoopExtractor.cpp - Extract each loop into a new function ----------===//
-//
+//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
//===----------------------------------------------------------------------===//
//
// A pass wrapper around the ExtractLoop() scalar transformation to extract each
//
//===----------------------------------------------------------------------===//
+#define DEBUG_TYPE "loop-extract"
+#include "llvm/Transforms/IPO.h"
+#include "llvm/Instructions.h"
#include "llvm/Module.h"
#include "llvm/Pass.h"
-#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/Analysis/Dominators.h"
+#include "llvm/Analysis/LoopPass.h"
+#include "llvm/Support/CommandLine.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/FunctionUtils.h"
-#include <vector>
+#include "llvm/ADT/Statistic.h"
+#include <fstream>
+#include <set>
using namespace llvm;
+STATISTIC(NumExtracted, "Number of loops extracted");
+
namespace {
- // FIXME: PassManager should allow Module passes to require FunctionPasses
- struct LoopExtractor : public FunctionPass {
- virtual bool run(Module &M);
- virtual bool runOnFunction(Function &F);
-
+ struct LoopExtractor : public LoopPass {
+ static char ID; // Pass identification, replacement for typeid
+ unsigned NumLoops;
+
+ explicit LoopExtractor(unsigned numLoops = ~0)
+ : LoopPass(&ID), NumLoops(numLoops) {}
+
+ virtual bool runOnLoop(Loop *L, LPPassManager &LPM);
+
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
- AU.addRequired<LoopInfo>();
+ AU.addRequiredID(BreakCriticalEdgesID);
+ AU.addRequiredID(LoopSimplifyID);
+ AU.addRequired<DominatorTree>();
}
};
+}
- RegisterOpt<LoopExtractor>
- X("loop-extract", "Extract loops into new functions");
-} // End anonymous namespace
+char LoopExtractor::ID = 0;
+static RegisterPass<LoopExtractor>
+X("loop-extract", "Extract loops into new functions");
-bool LoopExtractor::run(Module &M) {
- bool Changed = false;
- for (Module::iterator i = M.begin(), e = M.end(); i != e; ++i)
- Changed |= runOnFunction(*i);
- return Changed;
-}
+namespace {
+ /// SingleLoopExtractor - For bugpoint.
+ struct SingleLoopExtractor : public LoopExtractor {
+ static char ID; // Pass identification, replacement for typeid
+ SingleLoopExtractor() : LoopExtractor(1) {}
+ };
+} // End anonymous namespace
-bool LoopExtractor::runOnFunction(Function &F) {
- std::cerr << F.getName() << "\n";
+char SingleLoopExtractor::ID = 0;
+static RegisterPass<SingleLoopExtractor>
+Y("loop-extract-single", "Extract at most one loop into a new function");
- LoopInfo &LI = getAnalysis<LoopInfo>();
+// createLoopExtractorPass - This pass extracts all natural loops from the
+// program into a function if it can.
+//
+Pass *llvm::createLoopExtractorPass() { return new LoopExtractor(); }
+
+bool LoopExtractor::runOnLoop(Loop *L, LPPassManager &LPM) {
+ // Only visit top-level loops.
+ if (L->getParentLoop())
+ return false;
- // We don't want to keep extracting the only loop of a function into a new one
- if (LI.begin() == LI.end() || LI.begin() + 1 == LI.end())
+ // If LoopSimplify form is not available, stay out of trouble.
+ if (!L->isLoopSimplifyForm())
return false;
+ DominatorTree &DT = getAnalysis<DominatorTree>();
bool Changed = false;
- // Try to move each loop out of the code into separate function
- for (LoopInfo::iterator i = LI.begin(), e = LI.end(); i != e; ++i)
- Changed |= (ExtractLoop(*i) != 0);
+ // If there is more than one top-level loop in this function, extract all of
+ // the loops. Otherwise there is exactly one top-level loop; in this case if
+ // this function is more than a minimal wrapper around the loop, extract
+ // the loop.
+ bool ShouldExtractLoop = false;
+
+ // Extract the loop if the entry block doesn't branch to the loop header.
+ TerminatorInst *EntryTI =
+ L->getHeader()->getParent()->getEntryBlock().getTerminator();
+ if (!isa<BranchInst>(EntryTI) ||
+ !cast<BranchInst>(EntryTI)->isUnconditional() ||
+ EntryTI->getSuccessor(0) != L->getHeader())
+ ShouldExtractLoop = true;
+ else {
+ // Check to see if any exits from the loop are more than just return
+ // blocks.
+ SmallVector<BasicBlock*, 8> ExitBlocks;
+ L->getExitBlocks(ExitBlocks);
+ for (unsigned i = 0, e = ExitBlocks.size(); i != e; ++i)
+ if (!isa<ReturnInst>(ExitBlocks[i]->getTerminator())) {
+ ShouldExtractLoop = true;
+ break;
+ }
+ }
+ if (ShouldExtractLoop) {
+ if (NumLoops == 0) return Changed;
+ --NumLoops;
+ if (ExtractLoop(DT, L) != 0) {
+ Changed = true;
+ // After extraction, the loop is replaced by a function call, so
+ // we shouldn't try to run any more loop passes on it.
+ LPM.deleteLoopFromQueue(L);
+ }
+ ++NumExtracted;
+ }
return Changed;
}
-/// createLoopExtractorPass
-///
-FunctionPass* llvm::createLoopExtractorPass() {
- return new LoopExtractor();
+// createSingleLoopExtractorPass - This pass extracts one natural loop from the
+// program into a function if it can. This is used by bugpoint.
+//
+Pass *llvm::createSingleLoopExtractorPass() {
+ return new SingleLoopExtractor();
+}
+
+
+// BlockFile - A file which contains a list of blocks that should not be
+// extracted.
+static cl::opt<std::string>
+BlockFile("extract-blocks-file", cl::value_desc("filename"),
+ cl::desc("A file containing list of basic blocks to not extract"),
+ cl::Hidden);
+
+namespace {
+ /// BlockExtractorPass - This pass is used by bugpoint to extract all blocks
+ /// from the module into their own functions except for those specified by the
+ /// BlocksToNotExtract list.
+ class BlockExtractorPass : public ModulePass {
+ void LoadFile(const char *Filename);
+
+ std::vector<BasicBlock*> BlocksToNotExtract;
+ std::vector<std::pair<std::string, std::string> > BlocksToNotExtractByName;
+ public:
+ static char ID; // Pass identification, replacement for typeid
+ explicit BlockExtractorPass(const std::vector<BasicBlock*> &B)
+ : ModulePass(&ID), BlocksToNotExtract(B) {
+ if (!BlockFile.empty())
+ LoadFile(BlockFile.c_str());
+ }
+ BlockExtractorPass() : ModulePass(&ID) {}
+
+ bool runOnModule(Module &M);
+ };
+}
+
+char BlockExtractorPass::ID = 0;
+static RegisterPass<BlockExtractorPass>
+XX("extract-blocks", "Extract Basic Blocks From Module (for bugpoint use)");
+
+// createBlockExtractorPass - This pass extracts all blocks (except those
+// specified in the argument list) from the functions in the module.
+//
+ModulePass *llvm::createBlockExtractorPass(const std::vector<BasicBlock*> &BTNE)
+{
+ return new BlockExtractorPass(BTNE);
+}
+
+void BlockExtractorPass::LoadFile(const char *Filename) {
+ // Load the BlockFile...
+ std::ifstream In(Filename);
+ if (!In.good()) {
+ errs() << "WARNING: BlockExtractor couldn't load file '" << Filename
+ << "'!\n";
+ return;
+ }
+ while (In) {
+ std::string FunctionName, BlockName;
+ In >> FunctionName;
+ In >> BlockName;
+ if (!BlockName.empty())
+ BlocksToNotExtractByName.push_back(
+ std::make_pair(FunctionName, BlockName));
+ }
+}
+
+bool BlockExtractorPass::runOnModule(Module &M) {
+ std::set<BasicBlock*> TranslatedBlocksToNotExtract;
+ for (unsigned i = 0, e = BlocksToNotExtract.size(); i != e; ++i) {
+ BasicBlock *BB = BlocksToNotExtract[i];
+ Function *F = BB->getParent();
+
+ // Map the corresponding function in this module.
+ Function *MF = M.getFunction(F->getName());
+ assert(MF->getFunctionType() == F->getFunctionType() && "Wrong function?");
+
+ // Figure out which index the basic block is in its function.
+ Function::iterator BBI = MF->begin();
+ std::advance(BBI, std::distance(F->begin(), Function::iterator(BB)));
+ TranslatedBlocksToNotExtract.insert(BBI);
+ }
+
+ while (!BlocksToNotExtractByName.empty()) {
+ // There's no way to find BBs by name without looking at every BB inside
+ // every Function. Fortunately, this is always empty except when used by
+ // bugpoint in which case correctness is more important than performance.
+
+ std::string &FuncName = BlocksToNotExtractByName.back().first;
+ std::string &BlockName = BlocksToNotExtractByName.back().second;
+
+ for (Module::iterator FI = M.begin(), FE = M.end(); FI != FE; ++FI) {
+ Function &F = *FI;
+ if (F.getName() != FuncName) continue;
+
+ for (Function::iterator BI = F.begin(), BE = F.end(); BI != BE; ++BI) {
+ BasicBlock &BB = *BI;
+ if (BB.getName() != BlockName) continue;
+
+ TranslatedBlocksToNotExtract.insert(BI);
+ }
+ }
+
+ BlocksToNotExtractByName.pop_back();
+ }
+
+ // Now that we know which blocks to not extract, figure out which ones we WANT
+ // to extract.
+ std::vector<BasicBlock*> BlocksToExtract;
+ for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F)
+ for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
+ if (!TranslatedBlocksToNotExtract.count(BB))
+ BlocksToExtract.push_back(BB);
+
+ for (unsigned i = 0, e = BlocksToExtract.size(); i != e; ++i)
+ ExtractBasicBlock(BlocksToExtract[i]);
+
+ return !BlocksToExtract.empty();
}
projects / oota-llvm.git / blobdiff