Begin collecting some of the statistics for block placement discussed on

the mailing list. Suggestions for other statistics to collect would be
awesome. =]

Currently these are implemented as a separate pass guarded by a separate
flag. I'm not thrilled by that, but I wanted to be able to collect the
statistics for the old code placement as well as the new in order to
have a point of comparison. I'm planning on folding them into the single
pass if / when there is only one pass of interest.

llvm-svn: 143537

1 files changed, 8 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/LLVMTargetMachine.cpp b/llvm/lib/CodeGen/LLVMTargetMachine.cpp
index 268584c06c1..3e69069fa95 100644
--- a/llvm/lib/CodeGen/LLVMTargetMachine.cpp
+++ b/llvm/lib/CodeGen/LLVMTargetMachine.cpp
@@ -55,6 +55,8 @@ static cl::opt<bool> DisableEarlyTailDup("disable-early-taildup", cl::Hidden,
     cl::desc("Disable pre-register allocation tail duplication"));
 static cl::opt<bool> EnableBlockPlacement("enable-block-placement",
     cl::Hidden, cl::desc("Enable probability-driven block placement"));
+static cl::opt<bool> EnableBlockPlacementStats("enable-block-placement-stats",
+    cl::Hidden, cl::desc("Collect probability-driven block placement stats"));
 static cl::opt<bool> DisableCodePlace("disable-code-place", cl::Hidden,
     cl::desc("Disable code placement"));
 static cl::opt<bool> DisableSSC("disable-ssc", cl::Hidden,
@@ -499,6 +501,12 @@ bool LLVMTargetMachine::addCommonCodeGenPasses(PassManagerBase &PM,
       PM.add(createCodePlacementOptPass());
       printNoVerify(PM, "After CodePlacementOpt");
     }
+
+    // Run a separate pass to collect block placement statistics.
+    if (EnableBlockPlacementStats) {
+      PM.add(createMachineBlockPlacementStatsPass());
+      printNoVerify(PM, "After MachineBlockPlacementStats");
+    }
   }
 
   if (addPreEmitPass(PM, OptLevel))