From 99827e861f8b2407778154ab582bdcd9bb88ead0 Mon Sep 17 00:00:00 2001
From: Jakob Stoklund Olesen <stoklund@2pi.dk>
Date: Thu, 17 Feb 2011 22:53:48 +0000
Subject: [PATCH] Add basic register allocator statistics.

llvm-svn: 125789
---
 llvm/lib/CodeGen/RegAllocBasic.cpp  |  8 ++++++++
 llvm/lib/CodeGen/RegAllocGreedy.cpp | 10 ++++++++++
 2 files changed, 18 insertions(+)

diff --git a/llvm/lib/CodeGen/RegAllocBasic.cpp b/llvm/lib/CodeGen/RegAllocBasic.cpp
index 7fbb035ed617..c0d4d8146a81 100644
--- a/llvm/lib/CodeGen/RegAllocBasic.cpp
+++ b/llvm/lib/CodeGen/RegAllocBasic.cpp
@@ -20,6 +20,7 @@
 #include "VirtRegMap.h"
 #include "VirtRegRewriter.h"
 #include "llvm/ADT/OwningPtr.h"
+#include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/AliasAnalysis.h"
 #include "llvm/Function.h"
 #include "llvm/PassAnalysisSupport.h"
@@ -48,6 +49,10 @@
 
 using namespace llvm;
 
+STATISTIC(NumAssigned     , "Number of registers assigned");
+STATISTIC(NumUnassigned   , "Number of registers unassigned");
+STATISTIC(NumNewQueued    , "Number of new live ranges queued");
+
 static RegisterRegAlloc basicRegAlloc("basic", "basic register allocator",
                                       createBasicRegisterAllocator);
 
@@ -242,12 +247,14 @@ void RegAllocBase::assign(LiveInterval &VirtReg, unsigned PhysReg) {
   assert(!VRM->hasPhys(VirtReg.reg) && "Duplicate VirtReg assignment");
   VRM->assignVirt2Phys(VirtReg.reg, PhysReg);
   PhysReg2LiveUnion[PhysReg].unify(VirtReg);
+  ++NumAssigned;
 }
 
 void RegAllocBase::unassign(LiveInterval &VirtReg, unsigned PhysReg) {
   assert(VRM->getPhys(VirtReg.reg) == PhysReg && "Inconsistent unassign");
   PhysReg2LiveUnion[PhysReg].extract(VirtReg);
   VRM->clearVirt(VirtReg.reg);
+  ++NumUnassigned;
 }
 
 // Top-level driver to manage the queue of unassigned VirtRegs and call the
@@ -287,6 +294,7 @@ void RegAllocBase::allocatePhysRegs() {
              "expect split value in virtual register");
       VirtRegQ.push(std::make_pair(getPriority(SplitVirtReg),
                                    SplitVirtReg->reg));
+      ++NumNewQueued;
     }
   }
 }
diff --git a/llvm/lib/CodeGen/RegAllocGreedy.cpp b/llvm/lib/CodeGen/RegAllocGreedy.cpp
index ab56ec32721d..7c35ceb1f561 100644
--- a/llvm/lib/CodeGen/RegAllocGreedy.cpp
+++ b/llvm/lib/CodeGen/RegAllocGreedy.cpp
@@ -22,6 +22,7 @@
 #include "SplitKit.h"
 #include "VirtRegMap.h"
 #include "VirtRegRewriter.h"
+#include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/AliasAnalysis.h"
 #include "llvm/Function.h"
 #include "llvm/PassAnalysisSupport.h"
@@ -45,6 +46,11 @@
 
 using namespace llvm;
 
+STATISTIC(NumGlobalSplits, "Number of split global live ranges");
+STATISTIC(NumLocalSplits,  "Number of split local live ranges");
+STATISTIC(NumReassigned,   "Number of interferences reassigned");
+STATISTIC(NumEvicted,      "Number of interferences evicted");
+
 static RegisterRegAlloc greedyRegAlloc("greedy", "greedy register allocator",
                                        createGreedyRegisterAllocator);
 
@@ -265,6 +271,7 @@ bool RAGreedy::reassignVReg(LiveInterval &InterferingVReg,
           TRI->getName(OldAssign) << " to " << TRI->getName(PhysReg) << '\n');
     unassign(InterferingVReg, OldAssign);
     assign(InterferingVReg, PhysReg);
+    ++NumReassigned;
     return true;
   }
   return false;
@@ -307,6 +314,7 @@ unsigned RAGreedy::tryReassignOrEvict(LiveInterval &VirtReg,
   if (BestVirt) {
     DEBUG(dbgs() << "evicting lighter " << *BestVirt << '\n');
     unassign(*BestVirt, VRM->getPhys(BestVirt->reg));
+    ++NumEvicted;
     NewVRegs.push_back(BestVirt);
     return BestPhys;
   }
@@ -782,6 +790,7 @@ void RAGreedy::splitAroundRegion(LiveInterval &VirtReg, unsigned PhysReg,
   // per-block segments? The current approach allows the stack region to
   // separate into connected components. Some components may be allocatable.
   SE.finish();
+  ++NumGlobalSplits;
 
   if (VerifyEnabled) {
     MF->verify(this, "After splitting live range around region");
@@ -1094,6 +1103,7 @@ unsigned RAGreedy::tryLocalSplit(LiveInterval &VirtReg, AllocationOrder &Order,
   SE.useIntv(SegStart, SegStop);
   SE.closeIntv();
   SE.finish();
+  ++NumLocalSplits;
 
   return 0;
 }