Add SplitAnalysis::getNumLiveBlocks().

It is important that this function returns the same number of live blocks as
countLiveBlocks(CurLI) because live range splitting uses the number of live
blocks to ensure it is making progress.

This is in preparation of supporting duplicate UseBlock entries for basic blocks
that have a virtual register live-in and live-out, but not live-though.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132244 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/RegAllocGreedy.cpp b/lib/CodeGen/RegAllocGreedy.cpp
index af77b476c81cb4429191674693e39029e76f7a0a..2d03760fc76508b163fa6a6d7b92ed08f805c04d 100644 (file)
--- a/lib/CodeGen/RegAllocGreedy.cpp
+++ b/lib/CodeGen/RegAllocGreedy.cpp
@@ -976,7 +976,7 @@ void RAGreedy::splitAroundRegion(LiveInterval &VirtReg,
   DebugVars->splitRegister(VirtReg.reg, LREdit.regs());
 
   LRStage.resize(MRI->getNumVirtRegs());
-  unsigned OrigBlocks = SA->getNumThroughBlocks() + SA->getUseBlocks().size();
+  unsigned OrigBlocks = SA->getNumLiveBlocks();
 
   // Sort out the new intervals created by splitting. We get four kinds:
   // - Remainder intervals should not be split again.

diff --git a/lib/CodeGen/SplitKit.cpp b/lib/CodeGen/SplitKit.cpp
index 55ae97c792add0afdb9ebc6b04c0aa7c7cc51f74..53141b54c9fe34c4272f086153991400acf1df35 100644 (file)
--- a/lib/CodeGen/SplitKit.cpp
+++ b/lib/CodeGen/SplitKit.cpp
@@ -224,6 +224,8 @@ bool SplitAnalysis::calcLiveBlockInfo() {
     else
       MFI = LIS.getMBBFromIndex(LVI->start);
   }
+
+  assert(getNumLiveBlocks() == countLiveBlocks(CurLI) && "Bad block count");
   return true;
 }
 

diff --git a/lib/CodeGen/SplitKit.h b/lib/CodeGen/SplitKit.h
index 6305d0cc23502bfdda271843520c82165ea478cf..dc27486e73e9e993121086a4666b16b0b263efb9 100644 (file)
--- a/lib/CodeGen/SplitKit.h
+++ b/lib/CodeGen/SplitKit.h
@@ -147,7 +147,7 @@ public:
 
   /// getUseBlocks - Return an array of BlockInfo objects for the basic blocks
   /// where CurLI has uses.
-  ArrayRef<BlockInfo> getUseBlocks() { return UseBlocks; }
+  ArrayRef<BlockInfo> getUseBlocks() const { return UseBlocks; }
 
   /// getNumThroughBlocks - Return the number of through blocks.
   unsigned getNumThroughBlocks() const { return NumThroughBlocks; }
@@ -158,9 +158,14 @@ public:
   /// getThroughBlocks - Return the set of through blocks.
   const BitVector &getThroughBlocks() const { return ThroughBlocks; }
 
-  /// countLiveBlocks - Return the number of blocks where li is live.
-  /// This is guaranteed to return the same number as getNumThroughBlocks() +
-  /// getUseBlocks().size() after calling analyze(li).
+  /// getNumLiveBlocks - Return the number of blocks where CurLI is live.
+  unsigned getNumLiveBlocks() const {
+    return getUseBlocks().size() + getNumThroughBlocks();
+  }
+
+  /// countLiveBlocks - Return the number of blocks where li is live. This is
+  /// guaranteed to return the same number as getNumLiveBlocks() after calling
+  /// analyze(li).
   unsigned countLiveBlocks(const LiveInterval *li) const;
 
   typedef SmallPtrSet<const MachineBasicBlock*, 16> BlockPtrSet;