[PM/AA] Hoist the AliasResult enum out of the AliasAnalysis class.

[oota-llvm.git] / include / llvm / Analysis / BlockFrequencyInfoImpl.h

diff --git a/include/llvm/Analysis/BlockFrequencyInfoImpl.h b/include/llvm/Analysis/BlockFrequencyInfoImpl.h
index 020847798308a1465abf1158b3f4372a771e7574..bf24f66cbca95176ea81fd47c7cace4f43ba75e9 100644 (file)
--- a/include/llvm/Analysis/BlockFrequencyInfoImpl.h
+++ b/include/llvm/Analysis/BlockFrequencyInfoImpl.h
@@ -226,7 +226,7 @@ public:
     BlockNode getHeader() const { return Nodes[0]; }
     bool isIrreducible() const { return NumHeaders > 1; }
 
-    HeaderMassList::difference_type headerIndexFor(const BlockNode &B) {
+    HeaderMassList::difference_type getHeaderIndex(const BlockNode &B) {
       assert(isHeader(B) && "this is only valid on loop header blocks");
       if (isIrreducible())
         return std::lower_bound(Nodes.begin(), Nodes.begin() + NumHeaders, B) -
@@ -628,7 +628,7 @@ void IrreducibleGraph::addEdges(const BlockNode &Node,
   else
     addBlockEdges(*this, Irr, OuterLoop);
 }
-}
+} // namespace bfi_detail
 
 /// \brief Shared implementation for block frequency analysis.
 ///
@@ -716,6 +716,17 @@ void IrreducibleGraph::addEdges(const BlockNode &Node,
 ///         - Distribute the mass accordingly, dithering to minimize mass loss,
 ///           as described in \a distributeMass().
 ///
+///     In the case of irreducible loops, instead of a single loop header,
+///     there will be several. The computation of backedge masses is similar
+///     but instead of having a single backedge mass, there will be one
+///     backedge per loop header. In these cases, each backedge will carry
+///     a mass proportional to the edge weights along the corresponding
+///     path.
+///
+///     At the end of propagation, the full mass assigned to the loop will be
+///     distributed among the loop headers proportionally according to the
+///     mass flowing through their backedges.
+///
 ///     Finally, calculate the loop scale from the accumulated backedge mass.
 ///
 ///  3. Distribute mass in the function (\a computeMassInFunction()).
@@ -862,7 +873,7 @@ template <class BT> class BlockFrequencyInfoImpl : BlockFrequencyInfoImplBase {
   ///
   /// \pre \a computeMassInLoop() has been called for each subloop of \c
   /// OuterLoop.
-  /// \pre \c Insert points at the the last loop successfully processed by \a
+  /// \pre \c Insert points at the last loop successfully processed by \a
   /// computeMassInLoop().
   /// \pre \c OuterLoop has irreducible SCCs.
   void computeIrreducibleMass(LoopData *OuterLoop,
@@ -1122,7 +1133,7 @@ template <class BT> struct BlockEdgesAdder {
       G.addEdge(Irr, BFI.getNode(*I), OuterLoop);
   }
 };
-}
+} // namespace bfi_detail
 template <class BT>
 void BlockFrequencyInfoImpl<BT>::computeIrreducibleMass(
     LoopData *OuterLoop, std::list<LoopData>::iterator Insert) {