IR: Cleanup comments for Value, User, and MDNode

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

diff --git a/lib/IR/Value.cpp b/lib/IR/Value.cpp
index 94f979a300262936973370c58fb95c761d6bf59d..b5af72b858ea9df48bed461d3890ae2b26723c28 100644 (file)
--- a/lib/IR/Value.cpp
+++ b/lib/IR/Value.cpp
@@ -88,8 +88,6 @@ Value::~Value() {
   LeakDetector::removeGarbageObject(this);
 }
 
-/// hasNUses - Return true if this Value has exactly N users.
-///
 bool Value::hasNUses(unsigned N) const {
   const_use_iterator UI = use_begin(), E = use_end();
 
@@ -98,9 +96,6 @@ bool Value::hasNUses(unsigned N) const {
   return UI == E;
 }
 
-/// hasNUsesOrMore - Return true if this value has N users or more.  This is
-/// logically equivalent to getNumUses() >= N.
-///
 bool Value::hasNUsesOrMore(unsigned N) const {
   const_use_iterator UI = use_begin(), E = use_end();
 
@@ -110,8 +105,6 @@ bool Value::hasNUsesOrMore(unsigned N) const {
   return true;
 }
 
-/// isUsedInBasicBlock - Return true if this value is used in the specified
-/// basic block.
 bool Value::isUsedInBasicBlock(const BasicBlock *BB) const {
   // This can be computed either by scanning the instructions in BB, or by
   // scanning the use list of this Value. Both lists can be very long, but
@@ -133,10 +126,6 @@ bool Value::isUsedInBasicBlock(const BasicBlock *BB) const {
   return false;
 }
 
-
-/// getNumUses - This method computes the number of uses of this Value.  This
-/// is a linear time operation.  Use hasOneUse or hasNUses to check for specific
-/// values.
 unsigned Value::getNumUses() const {
   return (unsigned)std::distance(use_begin(), use_end());
 }
@@ -236,9 +225,6 @@ void Value::setName(const Twine &NewName) {
   Name = ST->createValueName(NameRef, this);
 }
 
-
-/// takeName - transfer the name from V to this value, setting V's name to
-/// empty.  It is an error to call V->takeName(V).
 void Value::takeName(Value *V) {
   assert(SubclassID != MDStringVal && "Cannot take the name of an MDString!");
 
@@ -303,7 +289,7 @@ void Value::takeName(Value *V) {
 }
 
 #ifndef NDEBUG
-static bool contains(SmallPtrSet<ConstantExpr *, 4> &Cache, ConstantExpr *Expr,
+static bool contains(SmallPtrSetImpl<ConstantExpr *> &Cache, ConstantExpr *Expr,
                      Constant *C) {
   if (!Cache.insert(Expr))
     return false;
@@ -455,7 +441,8 @@ Value *Value::stripAndAccumulateInBoundsConstantOffsets(const DataLayout &DL,
         return V;
       Offset = GEPOffset;
       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)) {
       V = GA->getAliasee();
@@ -472,10 +459,12 @@ Value *Value::stripInBoundsOffsets() {
   return stripPointerCastsAndOffsets<PSK_InBounds>(this);
 }
 
-/// isDereferenceablePointer - Test if this value is always a pointer to
-/// allocated and suitably aligned memory for a simple load or store.
+/// \brief Check if Value is always a dereferenceable pointer.
+///
+/// Test if V is always a pointer to allocated and suitably aligned memory for
+/// a simple load or store.
 static bool isDereferenceablePointer(const Value *V, const DataLayout *DL,
-                                     SmallPtrSet<const Value *, 32> &Visited) {
+                                     SmallPtrSetImpl<const Value *> &Visited) {
   // Note that it is not safe to speculate into a malloc'd region because
   // malloc may return null.
 
@@ -571,8 +560,6 @@ static bool isDereferenceablePointer(const Value *V, const DataLayout *DL,
   return false;
 }
 
-/// isDereferenceablePointer - Test if this value is always a pointer to
-/// allocated and suitably aligned memory for a simple load or store.
 bool Value::isDereferenceablePointer(const DataLayout *DL) const {
   // When dereferenceability information is provided by a dereferenceable
   // attribute, we know exactly how many bytes are dereferenceable. If we can
@@ -599,10 +586,6 @@ bool Value::isDereferenceablePointer(const DataLayout *DL) const {
   return ::isDereferenceablePointer(this, DL, Visited);
 }
 
-/// DoPHITranslation - If this value is a PHI node with CurBB as its parent,
-/// return the value in the PHI node corresponding to PredBB.  If not, return
-/// ourself.  This is useful if you want to know the value something has in a
-/// predecessor block.
 Value *Value::DoPHITranslation(const BasicBlock *CurBB,
                                const BasicBlock *PredBB) {
   PHINode *PN = dyn_cast<PHINode>(this);
@@ -613,12 +596,29 @@ Value *Value::DoPHITranslation(const BasicBlock *CurBB,
 
 LLVMContext &Value::getContext() const { return VTy->getContext(); }
 
+void Value::reverseUseList() {
+  if (!UseList || !UseList->Next)
+    // No need to reverse 0 or 1 uses.
+    return;
+
+  Use *Head = UseList;
+  Use *Current = UseList->Next;
+  Head->Next = nullptr;
+  while (Current) {
+    Use *Next = Current->Next;
+    Current->Next = Head;
+    Head->setPrev(&Current->Next);
+    Head = Current;
+    Current = Next;
+  }
+  UseList = Head;
+  Head->setPrev(&UseList);
+}
+
 //===----------------------------------------------------------------------===//
 //                             ValueHandleBase Class
 //===----------------------------------------------------------------------===//
 
-/// AddToExistingUseList - Add this ValueHandle to the use list for VP, where
-/// List is known to point into the existing use list.
 void ValueHandleBase::AddToExistingUseList(ValueHandleBase **List) {
   assert(List && "Handle list is null?");
 
@@ -642,7 +642,6 @@ void ValueHandleBase::AddToExistingUseListAfter(ValueHandleBase *List) {
     Next->setPrevPtr(&Next);
 }
 
-/// AddToUseList - Add this ValueHandle to the use list for VP.
 void ValueHandleBase::AddToUseList() {
   assert(VP.getPointer() && "Null pointer doesn't have a use list!");
 
@@ -686,7 +685,6 @@ void ValueHandleBase::AddToUseList() {
   }
 }
 
-/// RemoveFromUseList - Remove this ValueHandle from its current use list.
 void ValueHandleBase::RemoveFromUseList() {
   assert(VP.getPointer() && VP.getPointer()->HasValueHandle &&
          "Pointer doesn't have a use list!");