[llvm-commits] [llvm] r89254 - /llvm/trunk/lib/CodeGen/BranchFolding.cpp

[Bob Wilson]

Author: bwilson
Date: Wed Nov 18 16:12:31 2009
New Revision: 89254

URL: http://llvm.org/viewvc/llvm-project?rev=89254&view=rev
Log:
Add another statistic to measure code size due to tail duplication.

Modified:
    llvm/trunk/lib/CodeGen/BranchFolding.cpp

Modified: llvm/trunk/lib/CodeGen/BranchFolding.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/BranchFolding.cpp?rev=89254&r1=89253&r2=89254&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/BranchFolding.cpp (original)
+++ llvm/trunk/lib/CodeGen/BranchFolding.cpp Wed Nov 18 16:12:31 2009
@@ -42,6 +42,7 @@
 STATISTIC(NumBranchOpts, "Number of branches optimized");
 STATISTIC(NumTailMerge , "Number of block tails merged");
 STATISTIC(NumTailDups  , "Number of tail duplicated blocks");
+STATISTIC(NumInstrDups , "Additional instructions due to tail duplication");
 
 static cl::opt<cl::boolOrDefault> FlagEnableTailMerge("enable-tail-merge",
                               cl::init(cl::BOU_UNSET), cl::Hidden);
@@ -1020,6 +1021,7 @@
 
     // If it is dead, remove it.
     if (MBB->pred_empty()) {
+      NumInstrDups -= MBB->size();
       RemoveDeadBlock(MBB);
       MadeChange = true;
       ++NumDeadBlocks;
@@ -1100,6 +1102,7 @@
       MachineInstr *NewMI = MF.CloneMachineInstr(I);
       PredBB->insert(PredBB->end(), NewMI);
     }
+    NumInstrDups += TailBB->size() - 1; // subtract one for removed branch
 
     // Update the CFG.
     PredBB->removeSuccessor(PredBB->succ_begin());