[RS4GC] Fix rematerialization of bitcast of bitcast.

[oota-llvm.git] / lib / Analysis / LoopInfo.cpp

diff --git a/lib/Analysis/LoopInfo.cpp b/lib/Analysis/LoopInfo.cpp
index 3d30c3a06e2850cd895f2ad89e228f6a4ddb9fab..9ab9eead584fc64956114623d9d2e0a2f2b55acb 100644 (file)
--- a/lib/Analysis/LoopInfo.cpp
+++ b/lib/Analysis/LoopInfo.cpp
@@ -120,6 +120,13 @@ bool Loop::makeLoopInvariant(Instruction *I, bool &Changed,
 
   // Hoist.
   I->moveBefore(InsertPt);
+
+  // There is possibility of hoisting this instruction above some arbitrary
+  // condition. Any metadata defined on it can be control dependent on this
+  // condition. Conservatively strip it here so that we don't give any wrong
+  // information to the optimizer.
+  I->dropUnknownNonDebugMetadata();
+
   Changed = true;
   return true;
 }
@@ -172,7 +179,13 @@ PHINode *Loop::getCanonicalInductionVariable() const {
 bool Loop::isLCSSAForm(DominatorTree &DT) const {
   for (block_iterator BI = block_begin(), E = block_end(); BI != E; ++BI) {
     BasicBlock *BB = *BI;
-    for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E;++I)
+    for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E;++I) {
+      // Tokens can't be used in PHI nodes and live-out tokens prevent loop
+      // optimizations, so for the purposes of considered LCSSA form, we
+      // can ignore them.
+      if (I->getType()->isTokenTy())
+        continue;
+
       for (Use &U : I->uses()) {
         Instruction *UI = cast<Instruction>(U.getUser());
         BasicBlock *UserBB = UI->getParent();
@@ -188,11 +201,21 @@ bool Loop::isLCSSAForm(DominatorTree &DT) const {
             DT.isReachableFromEntry(UserBB))
           return false;
       }
+    }
   }
 
   return true;
 }
 
+bool Loop::isRecursivelyLCSSAForm(DominatorTree &DT) const {
+  if (!isLCSSAForm(DT))
+    return false;
+
+  return std::all_of(begin(), end(), [&](const Loop *L) {
+    return L->isRecursivelyLCSSAForm(DT);
+  });
+}
+
 /// isLoopSimplifyForm - Return true if the Loop is in the form that
 /// the LoopSimplify form transforms loops to, which is sometimes called
 /// normal form.
@@ -211,9 +234,15 @@ bool Loop::isSafeToClone() const {
     if (isa<IndirectBrInst>((*I)->getTerminator()))
       return false;
 
-    if (const InvokeInst *II = dyn_cast<InvokeInst>((*I)->getTerminator()))
+    if (const InvokeInst *II = dyn_cast<InvokeInst>((*I)->getTerminator())) {
       if (II->cannotDuplicate())
         return false;
+      // Return false if any loop blocks contain invokes to EH-pads other than
+      // landingpads;  we don't know how to split those edges yet.
+      auto *FirstNonPHI = II->getUnwindDest()->getFirstNonPHI();
+      if (FirstNonPHI->isEHPad() && !isa<LandingPadInst>(FirstNonPHI))
+        return false;
+    }
 
     for (BasicBlock::iterator BI = (*I)->begin(), BE = (*I)->end(); BI != BE; ++BI) {
       if (const CallInst *CI = dyn_cast<CallInst>(BI)) {
@@ -608,14 +637,8 @@ LoopInfo::LoopInfo(const DominatorTreeBase<BasicBlock> &DomTree) {
   analyze(DomTree);
 }
 
-/// updateUnloop - The last backedge has been removed from a loop--now the
-/// "unloop". Find a new parent for the blocks contained within unloop and
-/// update the loop tree. We don't necessarily have valid dominators at this
-/// point, but LoopInfo is still valid except for the removal of this loop.
-///
-/// Note that Unloop may now be an empty loop. Calling Loop::getHeader without
-/// checking first is illegal.
 void LoopInfo::updateUnloop(Loop *Unloop) {
+  Unloop->markUnlooped();
 
   // First handle the special case of no parent loop to simplify the algorithm.
   if (!Unloop->getParentLoop()) {
@@ -691,6 +714,20 @@ PreservedAnalyses LoopPrinterPass::run(Function &F,
   return PreservedAnalyses::all();
 }
 
+PrintLoopPass::PrintLoopPass() : OS(dbgs()) {}
+PrintLoopPass::PrintLoopPass(raw_ostream &OS, const std::string &Banner)
+    : OS(OS), Banner(Banner) {}
+
+PreservedAnalyses PrintLoopPass::run(Loop &L) {
+  OS << Banner;
+  for (auto *Block : L.blocks())
+    if (Block)
+      Block->print(OS);
+    else
+      OS << "Printing <null> block";
+  return PreservedAnalyses::all();
+}
+
 //===----------------------------------------------------------------------===//
 // LoopInfo implementation
 //