Reapply this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124779 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 36 insertions, 27 deletions

diff --git a/lib/CodeGen/SplitKit.h b/lib/CodeGen/SplitKit.h
index bb4fca9084..5e9b96b629 100644
--- a/lib/CodeGen/SplitKit.h
+++ b/lib/CodeGen/SplitKit.h
@@ -13,11 +13,13 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/IntervalMap.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/CodeGen/SlotIndexes.h"
 
 namespace llvm {
 
+class ConnectedVNInfoEqClasses;
 class LiveInterval;
 class LiveIntervals;
 class LiveRangeEdit;
@@ -263,6 +265,10 @@ public:
   /// with defValue.
   bool isComplexMapped(const VNInfo *ParentVNI) const;
 
+  /// markComplexMapped - Mark ParentVNI as complex mapped regardless of the
+  /// number of definitions.
+  void markComplexMapped(const VNInfo *ParentVNI) { Values[ParentVNI] = 0; }
+
   // addSimpleRange - Add a simple range from ParentLI to LI.
   // ParentVNI must be live in the [Start;End) interval.
   void addSimpleRange(SlotIndex Start, SlotIndex End, const VNInfo *ParentVNI);
@@ -290,49 +296,49 @@ class SplitEditor {
   LiveIntervals &LIS;
   VirtRegMap &VRM;
   MachineRegisterInfo &MRI;
+  MachineDominatorTree &MDT;
   const TargetInstrInfo &TII;
   const TargetRegisterInfo &TRI;
 
   /// Edit - The current parent register and new intervals created.
   LiveRangeEdit &Edit;
 
-  /// DupLI - Created as a copy of CurLI, ranges are carved out as new
-  /// intervals get added through openIntv / closeIntv. This is used to avoid
-  /// editing CurLI.
-  LiveIntervalMap DupLI;
+  /// Index into Edit of the currently open interval.
+  /// The index 0 is used for the complement, so the first interval started by
+  /// openIntv will be 1.
+  unsigned OpenIdx;
+
+  typedef IntervalMap<SlotIndex, unsigned> RegAssignMap;
+
+  /// Allocator for the interval map. This will eventually be shared with
+  /// SlotIndexes and LiveIntervals.
+  RegAssignMap::Allocator Allocator;
+
+  /// RegAssign - Map of the assigned register indexes.
+  /// Edit.get(RegAssign.lookup(Idx)) is the register that should be live at
+  /// Idx.
+  RegAssignMap RegAssign;
 
-  /// Currently open LiveInterval.
-  LiveIntervalMap OpenLI;
+  /// LIMappers - One LiveIntervalMap or each interval in Edit.
+  SmallVector<LiveIntervalMap, 4> LIMappers;
 
   /// defFromParent - Define Reg from ParentVNI at UseIdx using either
   /// rematerialization or a COPY from parent. Return the new value.
-  VNInfo *defFromParent(LiveIntervalMap &Reg,
+  VNInfo *defFromParent(unsigned RegIdx,
                         VNInfo *ParentVNI,
                         SlotIndex UseIdx,
                         MachineBasicBlock &MBB,
                         MachineBasicBlock::iterator I);
 
-  /// intervalsLiveAt - Return true if any member of intervals_ is live at Idx.
-  bool intervalsLiveAt(SlotIndex Idx) const;
+  /// rewriteAssigned - Rewrite all uses of Edit.getReg() to assigned registers.
+  void rewriteAssigned();
 
-  /// Values in CurLI whose live range has been truncated when entering an open
-  /// li.
-  SmallPtrSet<const VNInfo*, 8> truncatedValues;
-
-  /// addTruncSimpleRange - Add the given simple range to DupLI after
-  /// truncating any overlap with intervals_.
-  void addTruncSimpleRange(SlotIndex Start, SlotIndex End, VNInfo *VNI);
-
-  /// criticalPreds_ - Set of basic blocks where both dupli and OpenLI should be
-  /// live out because of a critical edge.
-  SplitAnalysis::BlockPtrSet criticalPreds_;
-
-  /// computeRemainder - Compute the dupli liveness as the complement of all the
-  /// new intervals.
-  void computeRemainder();
-
-  /// rewrite - Rewrite all uses of reg to use the new registers.
-  void rewrite(unsigned reg);
+  /// rewriteComponents - Rewrite all uses of Intv[0] according to the eq
+  /// classes in ConEQ.
+  /// This must be done when Intvs[0] is styill live at all uses, before calling
+  /// ConEq.Distribute().
+  void rewriteComponents(const SmallVectorImpl<LiveInterval*> &Intvs,
+                         const ConnectedVNInfoEqClasses &ConEq);
 
 public:
   /// Create a new SplitEditor for editing the LiveInterval analyzed by SA.
@@ -374,6 +380,9 @@ public:
   /// remaining live range, and rewrite instructions to use the new registers.
   void finish();
 
+  /// dump - print the current interval maping to dbgs().
+  void dump() const;
+
   // ===--- High level methods ---===
 
   /// splitAroundLoop - Split CurLI into a separate live interval inside