#define DEBUG_TYPE "loop-extract"
#include "llvm/Transforms/IPO.h"
-#include "llvm/Instructions.h"
-#include "llvm/Module.h"
-#include "llvm/Pass.h"
+#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/Dominators.h"
#include "llvm/Analysis/LoopPass.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Transforms/Scalar.h"
-#include "llvm/Transforms/Utils/FunctionUtils.h"
-#include "llvm/ADT/Statistic.h"
+#include "llvm/Transforms/Utils/BasicBlockUtils.h"
+#include "llvm/Transforms/Utils/CodeExtractor.h"
#include <fstream>
#include <set>
using namespace llvm;
char LoopExtractor::ID = 0;
INITIALIZE_PASS_BEGIN(LoopExtractor, "loop-extract",
- "Extract loops into new functions", false, false)
+ "Extract loops into new functions", false, false)
INITIALIZE_PASS_DEPENDENCY(BreakCriticalEdges)
INITIALIZE_PASS_DEPENDENCY(LoopSimplify)
INITIALIZE_PASS_DEPENDENCY(DominatorTree)
INITIALIZE_PASS_END(LoopExtractor, "loop-extract",
- "Extract loops into new functions", false, false)
+ "Extract loops into new functions", false, false)
namespace {
/// SingleLoopExtractor - For bugpoint.
L->getHeader()->getParent()->getEntryBlock().getTerminator();
if (!isa<BranchInst>(EntryTI) ||
!cast<BranchInst>(EntryTI)->isUnconditional() ||
- EntryTI->getSuccessor(0) != L->getHeader())
+ EntryTI->getSuccessor(0) != L->getHeader()) {
ShouldExtractLoop = true;
- else {
+ } else {
// Check to see if any exits from the loop are more than just return
// blocks.
SmallVector<BasicBlock*, 8> ExitBlocks;
break;
}
}
+
+ if (ShouldExtractLoop) {
+ // We must omit landing pads. Landing pads must accompany the invoke
+ // instruction. But this would result in a loop in the extracted
+ // function. An infinite cycle occurs when it tries to extract that loop as
+ // well.
+ SmallVector<BasicBlock*, 8> ExitBlocks;
+ L->getExitBlocks(ExitBlocks);
+ for (unsigned i = 0, e = ExitBlocks.size(); i != e; ++i)
+ if (ExitBlocks[i]->isLandingPad()) {
+ ShouldExtractLoop = false;
+ break;
+ }
+ }
+
if (ShouldExtractLoop) {
if (NumLoops == 0) return Changed;
--NumLoops;
- if (ExtractLoop(DT, L) != 0) {
+ CodeExtractor Extractor(DT, *L);
+ if (Extractor.extractCodeRegion() != 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.
/// BlocksToNotExtract list.
class BlockExtractorPass : public ModulePass {
void LoadFile(const char *Filename);
+ void SplitLandingPadPreds(Function *F);
std::vector<BasicBlock*> BlocksToNotExtract;
std::vector<std::pair<std::string, std::string> > BlocksToNotExtractByName;
// createBlockExtractorPass - This pass extracts all blocks (except those
// specified in the argument list) from the functions in the module.
//
-ModulePass *llvm::createBlockExtractorPass()
-{
+ModulePass *llvm::createBlockExtractorPass() {
return new BlockExtractorPass();
}
}
}
+/// SplitLandingPadPreds - The landing pad needs to be extracted with the invoke
+/// instruction. The critical edge breaker will refuse to break critical edges
+/// to a landing pad. So do them here. After this method runs, all landing pads
+/// should have only one predecessor.
+void BlockExtractorPass::SplitLandingPadPreds(Function *F) {
+ for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
+ InvokeInst *II = dyn_cast<InvokeInst>(I);
+ if (!II) continue;
+ BasicBlock *Parent = II->getParent();
+ BasicBlock *LPad = II->getUnwindDest();
+
+ // Look through the landing pad's predecessors. If one of them ends in an
+ // 'invoke', then we want to split the landing pad.
+ bool Split = false;
+ for (pred_iterator
+ PI = pred_begin(LPad), PE = pred_end(LPad); PI != PE; ++PI) {
+ BasicBlock *BB = *PI;
+ if (BB->isLandingPad() && BB != Parent &&
+ isa<InvokeInst>(Parent->getTerminator())) {
+ Split = true;
+ break;
+ }
+ }
+
+ if (!Split) continue;
+
+ SmallVector<BasicBlock*, 2> NewBBs;
+ SplitLandingPadPredecessors(LPad, Parent, ".1", ".2", 0, NewBBs);
+ }
+}
+
bool BlockExtractorPass::runOnModule(Module &M) {
std::set<BasicBlock*> TranslatedBlocksToNotExtract;
for (unsigned i = 0, e = BlocksToNotExtract.size(); i != e; ++i) {
// 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 (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) {
+ SplitLandingPadPreds(&*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]);
+ for (unsigned i = 0, e = BlocksToExtract.size(); i != e; ++i) {
+ SmallVector<BasicBlock*, 2> BlocksToExtractVec;
+ BlocksToExtractVec.push_back(BlocksToExtract[i]);
+ if (const InvokeInst *II =
+ dyn_cast<InvokeInst>(BlocksToExtract[i]->getTerminator()))
+ BlocksToExtractVec.push_back(II->getUnwindDest());
+ CodeExtractor(BlocksToExtractVec).extractCodeRegion();
+ }
return !BlocksToExtract.empty();
}