Revert r199628: "[AArch64 NEON] Fix a bug caused by undef lane when generating VEXT."

[oota-llvm.git] / lib / IR / Value.cpp

diff --git a/lib/IR/Value.cpp b/lib/IR/Value.cpp
index 81d7efa77408b0558b7fba324a9fc35334b8b57a..2c90383edd8c2ecff8e015ac161529f94f216758 100644 (file)
--- a/lib/IR/Value.cpp
+++ b/lib/IR/Value.cpp
@@ -182,6 +182,8 @@ void Value::setName(const Twine &NewName) {
 
   SmallString<256> NameData;
   StringRef NameRef = NewName.toStringRef(NameData);
+  assert(NameRef.find_first_of(0) == StringRef::npos &&
+         "Null bytes are not allowed in names");
 
   // Name isn't changing?
   if (getName() == NameRef)
@@ -365,7 +367,8 @@ static Value *stripPointerCastsAndOffsets(Value *V) {
         break;
       }
       V = GEP->getPointerOperand();
-    } else if (Operator::getOpcode(V) == Instruction::BitCast) {
+    } else if (Operator::getOpcode(V) == Instruction::BitCast ||
+               Operator::getOpcode(V) == Instruction::AddrSpaceCast) {
       V = cast<Operator>(V)->getOperand(0);
     } else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) {
       if (StripKind == PSK_ZeroIndices || GA->mayBeOverridden())
@@ -393,6 +396,42 @@ Value *Value::stripInBoundsConstantOffsets() {
   return stripPointerCastsAndOffsets<PSK_InBoundsConstantIndices>(this);
 }
 
+Value *Value::stripAndAccumulateInBoundsConstantOffsets(const DataLayout &DL,
+                                                        APInt &Offset) {
+  if (!getType()->isPointerTy())
+    return this;
+
+  assert(Offset.getBitWidth() == DL.getPointerSizeInBits(cast<PointerType>(
+                                     getType())->getAddressSpace()) &&
+         "The offset must have exactly as many bits as our pointer.");
+
+  // Even though we don't look through PHI nodes, we could be called on an
+  // instruction in an unreachable block, which may be on a cycle.
+  SmallPtrSet<Value *, 4> Visited;
+  Visited.insert(this);
+  Value *V = this;
+  do {
+    if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
+      if (!GEP->isInBounds())
+        return V;
+      APInt GEPOffset(Offset);
+      if (!GEP->accumulateConstantOffset(DL, GEPOffset))
+        return V;
+      Offset = GEPOffset;
+      V = GEP->getPointerOperand();
+    } else if (Operator::getOpcode(V) == Instruction::BitCast) {
+      V = cast<Operator>(V)->getOperand(0);
+    } else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) {
+      V = GA->getAliasee();
+    } else {
+      return V;
+    }
+    assert(V->getType()->isPointerTy() && "Unexpected operand type!");
+  } while (Visited.insert(V));
+
+  return V;
+}
+
 Value *Value::stripInBoundsOffsets() {
   return stripPointerCastsAndOffsets<PSK_InBounds>(this);
 }
@@ -698,9 +737,5 @@ void ValueHandleBase::ValueIsRAUWd(Value *Old, Value *New) {
 #endif
 }
 
-// Default implementation for CallbackVH.
-void CallbackVH::allUsesReplacedWith(Value *) {}
-
-void CallbackVH::deleted() {
-  setValPtr(NULL);
-}
+// Pin the vtable to this file.
+void CallbackVH::anchor() {}