Const-correct and prevent a copy of a SmallPtrSet.

[oota-llvm.git] / lib / Transforms / Utils / SimplifyCFG.cpp

diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index 960b198f36bdf93c16a1b0cc57aa0e64b3b8a8f9..cc3fbb19a6e60f6581dab6d7fb6fb3f0841bca66 100644 (file)
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -43,6 +43,7 @@
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
+#include "llvm/Transforms/Utils/Local.h"
 #include <algorithm>
 #include <map>
 #include <set>
@@ -1040,6 +1041,13 @@ static bool HoistThenElseCodeToIf(BranchInst *BI, const DataLayout *DL) {
     if (!I2->use_empty())
       I2->replaceAllUsesWith(I1);
     I1->intersectOptionalDataWith(I2);
+    unsigned KnownIDs[] = {
+      LLVMContext::MD_tbaa,
+      LLVMContext::MD_range,
+      LLVMContext::MD_fpmath,
+      LLVMContext::MD_invariant_load
+    };
+    combineMetadata(I1, I2, KnownIDs);
     I2->eraseFromParent();
     Changed = true;
 
@@ -3624,6 +3632,16 @@ Value *SwitchLookupTable::BuildLookup(Value *Index, IRBuilder<> &Builder) {
                                  "switch.masked");
     }
     case ArrayKind: {
+      // Make sure the table index will not overflow when treated as signed.
+      IntegerType *IT = cast<IntegerType>(Index->getType());
+      uint64_t TableSize = Array->getInitializer()->getType()
+                                ->getArrayNumElements();
+      if (TableSize > (1ULL << (IT->getBitWidth() - 1)))
+        Index = Builder.CreateZExt(Index,
+                                   IntegerType::get(IT->getContext(),
+                                                    IT->getBitWidth() + 1),
+                                   "switch.tableidx.zext");
+
       Value *GEPIndices[] = { Builder.getInt32(0), Index };
       Value *GEP = Builder.CreateInBoundsGEP(Array, GEPIndices,
                                              "switch.gep");
@@ -3820,10 +3838,13 @@ static bool SwitchToLookupTable(SwitchInst *SI,
   const bool GeneratingCoveredLookupTable = MaxTableSize == TableSize;
   if (GeneratingCoveredLookupTable) {
     Builder.CreateBr(LookupBB);
-    SI->getDefaultDest()->removePredecessor(SI->getParent());
+    // We cached PHINodes in PHIs, to avoid accessing deleted PHINodes later,
+    // do not delete PHINodes here.
+    SI->getDefaultDest()->removePredecessor(SI->getParent(),
+                                            true/*DontDeleteUselessPHIs*/);
   } else {
     Value *Cmp = Builder.CreateICmpULT(TableIndex, ConstantInt::get(
-                                         MinCaseVal->getType(), TableSize));
+                                       MinCaseVal->getType(), TableSize));
     Builder.CreateCondBr(Cmp, LookupBB, SI->getDefaultDest());
   }
 
@@ -3998,7 +4019,7 @@ bool SimplifyCFGOpt::SimplifyUncondBranch(BranchInst *BI, IRBuilder<> &Builder){
     return true;
 
   // If the Terminator is the only non-phi instruction, simplify the block.
-  BasicBlock::iterator I = BB->getFirstNonPHIOrDbgOrLifetime();
+  BasicBlock::iterator I = BB->getFirstNonPHIOrDbg();
   if (I->isTerminator() && BB != &BB->getParent()->getEntryBlock() &&
       TryToSimplifyUncondBranchFromEmptyBlock(BB))
     return true;