Add some statistics to the splitting and spilling frameworks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130931 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/InlineSpiller.cpp

@@ -16,6 +16,7 @@
 #include "Spiller.h"
 #include "LiveRangeEdit.h"
 #include "VirtRegMap.h"
+#include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/AliasAnalysis.h"
 #include "llvm/CodeGen/LiveIntervalAnalysis.h"
 #include "llvm/CodeGen/LiveStackAnalysis.h"
@@ -31,6 +32,18 @@
 
 using namespace llvm;
 
+STATISTIC(NumSpilledRanges,   "Number of spilled live ranges");
+STATISTIC(NumSnippets,        "Number of snippets included in spills");
+STATISTIC(NumSpills,          "Number of spills inserted");
+STATISTIC(NumReloads,         "Number of reloads inserted");
+STATISTIC(NumFolded,          "Number of folded stack accesses");
+STATISTIC(NumFoldedLoads,     "Number of folded loads");
+STATISTIC(NumRemats,          "Number of rematerialized defs for spilling");
+STATISTIC(NumOmitReloadSpill, "Number of omitted spills after reloads");
+STATISTIC(NumHoistLocal,      "Number of locally hoisted spills");
+STATISTIC(NumHoistGlobal,     "Number of globally hoisted spills");
+STATISTIC(NumRedundantSpills, "Number of redundant spills identified");
+
 namespace {
 class InlineSpiller : public Spiller {
   MachineFunctionPass &Pass;
@@ -247,10 +260,11 @@ void InlineSpiller::collectRegsToSpill() {
     if (!isSnippet(SnipLI))
       continue;
     SnippetCopies.insert(MI);
-    if (!isRegToSpill(SnipReg))
-      RegsToSpill.push_back(SnipReg);
-
+    if (isRegToSpill(SnipReg))
+      continue;
+    RegsToSpill.push_back(SnipReg);
     DEBUG(dbgs() << "\talso spill snippet " << SnipLI << '\n');
+    ++NumSnippets;
   }
 }
 
@@ -469,9 +483,10 @@ bool InlineSpiller::hoistSpill(LiveInterval &SpillLI, MachineInstr *CopyMI) {
                << *StackInt << '\n');
 
   // Already spilled everywhere.
-  if (SVI.AllDefsAreReloads)
+  if (SVI.AllDefsAreReloads) {
+    ++NumOmitReloadSpill;
     return true;
-
+  }
   // We are going to spill SVI.SpillVNI immediately after its def, so clear out
   // any later spills of the same value.
   eliminateRedundantSpills(SibLI, SVI.SpillVNI);
@@ -493,6 +508,11 @@ bool InlineSpiller::hoistSpill(LiveInterval &SpillLI, MachineInstr *CopyMI) {
   LIS.InsertMachineInstrInMaps(MII);
   VRM.addSpillSlotUse(StackSlot, MII);
   DEBUG(dbgs() << "\thoisted: " << SVI.SpillVNI->def << '\t' << *MII);
+
+  if (MBB == CopyMI->getParent())
+    ++NumHoistLocal;
+  else
+    ++NumHoistGlobal;
   return true;
 }
 
@@ -547,6 +567,7 @@ void InlineSpiller::eliminateRedundantSpills(LiveInterval &SLI, VNInfo *VNI) {
         // eliminateDeadDefs won't normally remove stores, so switch opcode.
         MI->setDesc(TII.get(TargetOpcode::KILL));
         DeadDefs.push_back(MI);
+        ++NumRedundantSpills;
       }
     }
   } while (!WorkList.empty());
@@ -642,6 +663,7 @@ bool InlineSpiller::reMaterializeFor(LiveInterval &VirtReg,
   if (RM.OrigMI->getDesc().canFoldAsLoad() &&
       foldMemoryOperand(MI, Ops, RM.OrigMI)) {
     Edit->markRematerialized(RM.ParentVNI);
+    ++NumFoldedLoads;
     return true;
   }
 
@@ -668,6 +690,7 @@ bool InlineSpiller::reMaterializeFor(LiveInterval &VirtReg,
   VNInfo *DefVNI = NewLI.getNextValue(DefIdx, 0, LIS.getVNInfoAllocator());
   NewLI.addRange(LiveRange(DefIdx, UseIdx.getDefIndex(), DefVNI));
   DEBUG(dbgs() << "\tinterval: " << NewLI << '\n');
+  ++NumRemats;
   return true;
 }
 
@@ -794,6 +817,7 @@ bool InlineSpiller::foldMemoryOperand(MachineBasicBlock::iterator MI,
     VRM.addSpillSlotUse(StackSlot, FoldMI);
   MI->eraseFromParent();
   DEBUG(dbgs() << "\tfolded: " << *FoldMI);
+  ++NumFolded;
   return true;
 }
 
@@ -811,6 +835,7 @@ void InlineSpiller::insertReload(LiveInterval &NewLI,
   VNInfo *LoadVNI = NewLI.getNextValue(LoadIdx, 0,
                                        LIS.getVNInfoAllocator());
   NewLI.addRange(LiveRange(LoadIdx, Idx, LoadVNI));
+  ++NumReloads;
 }
 
 /// insertSpill - Insert a spill of NewLI.reg after MI.
@@ -825,6 +850,7 @@ void InlineSpiller::insertSpill(LiveInterval &NewLI, const LiveInterval &OldLI,
   DEBUG(dbgs() << "\tspilled: " << StoreIdx << '\t' << *MI);
   VNInfo *StoreVNI = NewLI.getNextValue(Idx, 0, LIS.getVNInfoAllocator());
   NewLI.addRange(LiveRange(Idx, StoreIdx, StoreVNI));
+  ++NumSpills;
 }
 
 /// spillAroundUses - insert spill code around each use of Reg.
@@ -972,6 +998,7 @@ void InlineSpiller::spillAll() {
 }
 
 void InlineSpiller::spill(LiveRangeEdit &edit) {
+  ++NumSpilledRanges;
   Edit = &edit;
   assert(!TargetRegisterInfo::isStackSlot(edit.getReg())
          && "Trying to spill a stack slot.");

lib/CodeGen/LiveRangeEdit.cpp

@@ -15,6 +15,7 @@
 #include "LiveRangeEdit.h"
 #include "VirtRegMap.h"
 #include "llvm/ADT/SetVector.h"
+#include "llvm/ADT/Statistic.h"
 #include "llvm/CodeGen/CalcSpillWeights.h"
 #include "llvm/CodeGen/LiveIntervalAnalysis.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
@@ -24,6 +25,10 @@
 
 using namespace llvm;
 
+STATISTIC(NumDCEDeleted,     "Number of instructions deleted by DCE");
+STATISTIC(NumDCEFoldedLoads, "Number of single use loads folded after DCE");
+STATISTIC(NumFracRanges,     "Number of live ranges fractured by DCE");
+
 LiveInterval &LiveRangeEdit::createFrom(unsigned OldReg,
                                         LiveIntervals &LIS,
                                         VirtRegMap &VRM) {
@@ -199,6 +204,7 @@ bool LiveRangeEdit::foldAsLoad(LiveInterval *LI,
   UseMI->eraseFromParent();
   DefMI->addRegisterDead(LI->reg, 0);
   Dead.push_back(DefMI);
+  ++NumDCEFoldedLoads;
   return true;
 }
 
@@ -269,6 +275,7 @@ void LiveRangeEdit::eliminateDeadDefs(SmallVectorImpl<MachineInstr*> &Dead,
         delegate_->LRE_WillEraseInstruction(MI);
       LIS.RemoveMachineInstrFromMaps(MI);
       MI->eraseFromParent();
+      ++NumDCEDeleted;
     }
 
     if (ToShrink.empty())
@@ -290,6 +297,7 @@ void LiveRangeEdit::eliminateDeadDefs(SmallVectorImpl<MachineInstr*> &Dead,
     unsigned NumComp = ConEQ.Classify(LI);
     if (NumComp <= 1)
       continue;
+    ++NumFracRanges;
     DEBUG(dbgs() << NumComp << " components: " << *LI << '\n');
     SmallVector<LiveInterval*, 8> Dups(1, LI);
     for (unsigned i = 1; i != NumComp; ++i) {

lib/CodeGen/SplitKit.cpp

@@ -30,6 +30,8 @@ using namespace llvm;
 
 STATISTIC(NumFinished, "Number of splits finished");
 STATISTIC(NumSimple,   "Number of splits that were simple");
+STATISTIC(NumCopies,   "Number of copies inserted for splitting");
+STATISTIC(NumRemats,   "Number of rematerialized defs for splitting");
 
 //===----------------------------------------------------------------------===//
 //                                 Split Analysis
@@ -589,12 +591,14 @@ VNInfo *SplitEditor::defFromParent(unsigned RegIdx,
   LiveRangeEdit::Remat RM(ParentVNI);
   if (Edit->canRematerializeAt(RM, UseIdx, true, LIS)) {
     Def = Edit->rematerializeAt(MBB, I, LI->reg, RM, LIS, TII, TRI, Late);
+    ++NumRemats;
   } else {
     // Can't remat, just insert a copy from parent.
     CopyMI = BuildMI(MBB, I, DebugLoc(), TII.get(TargetOpcode::COPY), LI->reg)
                .addReg(Edit->getReg());
     Def = LIS.getSlotIndexes()->insertMachineInstrInMaps(CopyMI, Late)
             .getDefIndex();
+    ++NumCopies;
   }
 
   // Define the value in Reg.