improve "cannot yet select" errors a trivial amount: now

[oota-llvm.git] / lib / CodeGen / SplitKit.h

diff --git a/lib/CodeGen/SplitKit.h b/lib/CodeGen/SplitKit.h
index f290eb646101b2ede3525d745d2095edf29feb73..a6ba37610a0b9d4dfcd5e991cc030cf210981f57 100644 (file)
--- a/lib/CodeGen/SplitKit.h
+++ b/lib/CodeGen/SplitKit.h
@@ -12,10 +12,13 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/IntEqClasses.h"
+#include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/CodeGen/SlotIndexes.h"
 
+#include <string>
+
 namespace llvm {
 
 class LiveInterval;
@@ -36,6 +39,40 @@ class MachineDominatorTree;
 template <class NodeT> class DomTreeNodeBase;
 typedef DomTreeNodeBase<MachineBasicBlock> MachineDomTreeNode;
 
+
+/// EdgeBundles - Group CFG edges into equivalence classes where registers must
+/// be allocated identically. This annotates the CFG to form a bipartite graph
+/// where each block is connected to an ingoing and an outgoing bundle.
+/// Edge bundles are simply numbered, there is no object representation.
+class EdgeBundles {
+  const MachineFunction *MF;
+
+  /// EC - Each edge bundle is an equivalence class. The keys are:
+  ///   2*BB->getNumber()   -> Ingoing bundle.
+  ///   2*BB->getNumber()+1 -> Outgoing bundle.
+  IntEqClasses EC;
+
+public:
+  /// compute - Compute the edge bundles for MF. Bundles depend only on the CFG.
+  void compute(const MachineFunction *MF);
+
+  /// getBundle - Return the ingoing (Out = false) or outgoing (Out = true)
+  /// bundle number for basic block #N
+  unsigned getBundle(unsigned N, bool Out) const { return EC[2 * N + Out]; }
+
+  /// getMachineFunction - Return the last machine function computed.
+  const MachineFunction *getMachineFunction() const { return MF; }
+
+  /// view - Visualize the annotated bipartite CFG with Graphviz.
+  void view() const;
+};
+
+/// Specialize WriteGraph, the standard implementation won't work.
+raw_ostream &WriteGraph(raw_ostream &O, const EdgeBundles &G,
+                        bool ShortNames = false,
+                        const std::string &Title = "");
+
+
 /// SplitAnalysis - Analyze a LiveInterval, looking for live range splitting
 /// opportunities.
 class SplitAnalysis {
@@ -141,6 +178,15 @@ public:
   /// separate register, or NULL.
   const MachineLoop *getBestSplitLoop();
 
+  /// isBypassLoop - Return true if curli is live through Loop and has no uses
+  /// inside the loop. Bypass loops are candidates for splitting because it can
+  /// prevent interference inside the loop.
+  bool isBypassLoop(const MachineLoop *Loop);
+
+  /// getBypassLoops - Get all the maximal bypass loops. These are the bypass
+  /// loops whose parent is not a bypass loop.
+  void getBypassLoops(LoopPtrSet&);
+
   /// getMultiUseBlocks - Add basic blocks to Blocks that may benefit from
   /// having curli split to a new live interval. Return true if Blocks can be
   /// passed to SplitEditor::splitSingleBlocks.