X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FSplitKit.h;h=cc41e2e321e839e0d850b366dbc4725aec348795;hb=b34d837397053da8e9bff90dd714e24f2a3b98b3;hp=a387896a5da8a0cc47c1f84f226ce6cb63f82aaa;hpb=fd5c51342a429ecab86a645282d0b36b216c0256;p=oota-llvm.git

diff --git a/lib/CodeGen/SplitKit.h b/lib/CodeGen/SplitKit.h
index a387896a5da..cc41e2e321e 100644
--- a/lib/CodeGen/SplitKit.h
+++ b/lib/CodeGen/SplitKit.h
@@ -144,6 +144,9 @@ public:
   /// isThroughBlock - Return true if CurLI is live through MBB without uses.
   bool isThroughBlock(unsigned MBB) const { return ThroughBlocks.test(MBB); }
 
+  /// getThroughBlocks - Return the set of through blocks.
+  const BitVector &getThroughBlocks() const { return ThroughBlocks; }
+
   typedef SmallPtrSet<const MachineBasicBlock*, 16> BlockPtrSet;
 
   /// getMultiUseBlocks - Add basic blocks to Blocks that may benefit from
@@ -228,6 +231,30 @@ class SplitEditor {
   // entry in LiveOutCache.
   BitVector LiveOutSeen;
 
+  /// LiveInBlock - Info for updateSSA() about a block where a register is
+  /// live-in.
+  /// The updateSSA caller provides DomNode and Kill inside MBB, updateSSA()
+  /// adds the computed live-in value.
+  struct LiveInBlock {
+    // Dominator tree node for the block.
+    // Cleared by updateSSA when the final value has been determined.
+    MachineDomTreeNode *DomNode;
+
+    // Live-in value filled in by updateSSA once it is known.
+    VNInfo *Value;
+
+    // Position in block where the live-in range ends, or SlotIndex() if the
+    // range passes through the block.
+    SlotIndex Kill;
+
+    LiveInBlock(MachineDomTreeNode *node) : DomNode(node), Value(0) {}
+  };
+
+  /// LiveInBlocks - List of live-in blocks used by findReachingDefs() and
+  /// updateSSA(). This list is usually empty, it exists here to avoid frequent
+  /// reallocations.
+  SmallVector<LiveInBlock, 16> LiveInBlocks;
+
   /// defValue - define a value in RegIdx from ParentVNI at Idx.
   /// Idx does not have to be ParentVNI->def, but it must be contained within
   /// ParentVNI's live range in ParentLI. The new value is added to the value
@@ -251,17 +278,22 @@ class SplitEditor {
   /// Insert PHIDefs as needed to preserve SSA form.
   void extendRange(unsigned RegIdx, SlotIndex Idx);
 
-  /// updateSSA - Insert PHIDefs as necessary and update LiveOutCache such that
-  /// Edit.get(RegIdx) is live-in to all the blocks in LiveIn.
-  /// Return the value that is eventually live-in to IdxMBB.
-  VNInfo *updateSSA(unsigned RegIdx,
-                    SmallVectorImpl<MachineDomTreeNode*> &LiveIn,
-                    SlotIndex Idx,
-                    const MachineBasicBlock *IdxMBB);
+  /// findReachingDefs - Starting from MBB, add blocks to LiveInBlocks until all
+  /// reaching defs for LI are found.
+  /// @param LI   Live interval whose value is needed.
+  /// @param MBB  Block where LI should be live-in.
+  /// @param Kill Kill point in MBB.
+  /// @return Unique value seen, or NULL.
+  VNInfo *findReachingDefs(LiveInterval *LI, MachineBasicBlock *MBB,
+                           SlotIndex Kill);
 
-  /// transferSimpleValues - Transfer simply defined values to the new ranges.
-  /// Return true if any complex ranges were skipped.
-  bool transferSimpleValues();
+  /// updateSSA - Compute and insert PHIDefs such that all blocks in
+  // LiveInBlocks get a known live-in value. Add live ranges to the blocks.
+  void updateSSA();
+
+  /// transferValues - Transfer values to the new ranges.
+  /// Return true if any ranges were skipped.
+  bool transferValues();
 
   /// extendPHIKillRanges - Extend the ranges of all values killed by original
   /// parent PHIDefs.
@@ -334,10 +366,6 @@ public:
   ///
   void overlapIntv(SlotIndex Start, SlotIndex End);
 
-  /// closeIntv - Indicate that we are done editing the currently open
-  /// LiveInterval, and ranges can be trimmed.
-  void closeIntv();
-
   /// finish - after all the new live ranges have been created, compute the
   /// remaining live range, and rewrite instructions to use the new registers.
   void finish();