1 files changed, 24 insertions, 11 deletions

diff --git a/lib/Transforms/InstCombine/InstCombineCalls.cpp b/lib/Transforms/InstCombine/InstCombineCalls.cpp
index 85251a83d4ea..0ebe3b45589e 100644
--- a/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -96,14 +96,23 @@ static unsigned EnforceKnownAlignment(Value *V,
 /// increase the alignment of the ultimate object, making this check succeed.
 unsigned InstCombiner::GetOrEnforceKnownAlignment(Value *V,
                                                   unsigned PrefAlign) {
-  unsigned BitWidth = TD ? TD->getTypeSizeInBits(V->getType()) :
-                      sizeof(PrefAlign) * CHAR_BIT;
+  assert(V->getType()->isPointerTy() &&
+         "GetOrEnforceKnownAlignment expects a pointer!");
+  unsigned BitWidth = TD ? TD->getPointerSizeInBits() : 64;
   APInt Mask = APInt::getAllOnesValue(BitWidth);
   APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
   ComputeMaskedBits(V, Mask, KnownZero, KnownOne);
   unsigned TrailZ = KnownZero.countTrailingOnes();
+
+  // Avoid trouble with rediculously large TrailZ values, such as
+  // those computed from a null pointer.
+  TrailZ = std::min(TrailZ, unsigned(sizeof(unsigned) * CHAR_BIT - 1));
+
   unsigned Align = 1u << std::min(BitWidth - 1, TrailZ);
 
+  // LLVM doesn't support alignments larger than this currently.
+  Align = std::min(Align, +Value::MaximumAlignment);
+
   if (PrefAlign > Align)
     Align = EnforceKnownAlignment(V, Align, PrefAlign);
   
@@ -529,7 +538,7 @@ Instruction *InstCombiner::visitCallInst(CallInst &CI) {
       // X + 0 -> {X, false}
       if (RHS->isZero()) {
         Constant *V[] = {
-          UndefValue::get(II->getCalledValue()->getType()),
+          UndefValue::get(II->getArgOperand(0)->getType()),
           ConstantInt::getFalse(II->getContext())
         };
         Constant *Struct = ConstantStruct::get(II->getContext(), V, 2, false);
@@ -630,8 +639,8 @@ Instruction *InstCombiner::visitCallInst(CallInst &CI) {
       cast<VectorType>(II->getArgOperand(0)->getType())->getNumElements();
     APInt DemandedElts(VWidth, 1);
     APInt UndefElts(VWidth, 0);
-    if (Value *V = SimplifyDemandedVectorElts(II->getArgOperand(0), DemandedElts,
-                                              UndefElts)) {
+    if (Value *V = SimplifyDemandedVectorElts(II->getArgOperand(0),
+                                              DemandedElts, UndefElts)) {
       II->setArgOperand(0, V);
       return II;
     }
@@ -655,8 +664,10 @@ Instruction *InstCombiner::visitCallInst(CallInst &CI) {
       
       if (AllEltsOk) {
         // Cast the input vectors to byte vectors.
-        Value *Op0 = Builder->CreateBitCast(II->getArgOperand(0), Mask->getType());
-        Value *Op1 = Builder->CreateBitCast(II->getArgOperand(1), Mask->getType());
+        Value *Op0 = Builder->CreateBitCast(II->getArgOperand(0),
+                                            Mask->getType());
+        Value *Op1 = Builder->CreateBitCast(II->getArgOperand(1),
+                                            Mask->getType());
         Value *Result = UndefValue::get(Op0->getType());
         
         // Only extract each element once.
@@ -772,13 +783,15 @@ protected:
     NewInstruction = IC->ReplaceInstUsesWith(*CI, With);
   }
   bool isFoldable(unsigned SizeCIOp, unsigned SizeArgOp, bool isString) const {
-    if (ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getArgOperand(SizeCIOp - CallInst::ArgOffset))) {
+    if (ConstantInt *SizeCI =
+                           dyn_cast<ConstantInt>(CI->getArgOperand(SizeCIOp))) {
       if (SizeCI->isAllOnesValue())
         return true;
       if (isString)
         return SizeCI->getZExtValue() >=
-               GetStringLength(CI->getArgOperand(SizeArgOp - CallInst::ArgOffset));
-      if (ConstantInt *Arg = dyn_cast<ConstantInt>(CI->getArgOperand(SizeArgOp - CallInst::ArgOffset)))
+               GetStringLength(CI->getArgOperand(SizeArgOp));
+      if (ConstantInt *Arg = dyn_cast<ConstantInt>(
+                                                  CI->getArgOperand(SizeArgOp)))
         return SizeCI->getZExtValue() >= Arg->getZExtValue();
     }
     return false;
@@ -1140,7 +1153,7 @@ Instruction *InstCombiner::transformCallThroughTrampoline(CallSite CS) {
   IntrinsicInst *Tramp =
     cast<IntrinsicInst>(cast<BitCastInst>(Callee)->getOperand(0));
 
-  Function *NestF = cast<Function>(Tramp->getArgOperand(1)->stripPointerCasts());
+  Function *NestF =cast<Function>(Tramp->getArgOperand(1)->stripPointerCasts());
   const PointerType *NestFPTy = cast<PointerType>(NestF->getType());
   const FunctionType *NestFTy = cast<FunctionType>(NestFPTy->getElementType());