Refactor debugging code, NFC.

[thanm]

Summary

Refactor debugging routines to reduce code duplication. Remove a couple
of #include's that were not needed. Don't require MachineDominator as a
prereq for this pass (not needed).

These changes split off from http://reviews.llvm.org/D18827.

[thanm]

Ping.

[george.burgess.iv]

Just a few comments, and this LGTM. Thanks for the patch!

lib/CodeGen/StackColoring.cpp

195

Nit: Please clang-format this, and the other DEBUG statements nearby (specifically, I think there should be a space between dbgs() and <<).

196

Nit: for (unsigned I = 0, E = BV.size(); I != E; ++I)

221

Nit: for (unsigned I = 0, E = Intervals.size(); I != E; ++I)

223

ISTM LiveInterval::dump will unconditionally dump things to dbgs(). So, maybe we should wrap this dump in DEBUG, too?

[thanm]

Incorporate code review feedback from gbiv.

[thanm]

Thanks George for your review comments (just getting back to this after a hiatus).
Will submit the changes. shortly.

lib/CodeGen/StackColoring.cpp

 #include "llvm/ADT/PostOrderIterator.h"
 #include "llvm/ADT/SetVector.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SparseSet.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/ValueTracking.h"
 #include "llvm/CodeGen/LiveInterval.h"
 #include "llvm/CodeGen/MachineBasicBlock.h"
-#include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
-#include "llvm/CodeGen/MachineDominators.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/CodeGen/MachineLoopInfo.h"
 #include "llvm/CodeGen/MachineMemOperand.h"
 #include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/Passes.h"
 #include "llvm/CodeGen/PseudoSourceValue.h"
 #include "llvm/CodeGen/SlotIndexes.h"
 #include "llvm/CodeGen/StackProtector.h"
 #include "llvm/CodeGen/WinEHFuncInfo.h"
 #include "llvm/IR/DebugInfo.h"
-#include "llvm/IR/Dominators.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/Module.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Target/TargetInstrInfo.h"
StackColoring() : MachineFunctionPass(ID) {
     initializeStackColoringPass(*PassRegistry::getPassRegistry());
   }
   void getAnalysisUsage(AnalysisUsage &AU) const override;
   bool runOnMachineFunction(MachineFunction &MF) override;
 
 private:
   /// Debug.
   void dump() const;
+  void dumpIntervals() const;
+  void dumpBB(MachineBasicBlock *MBB) const;
+  void dumpBV(const char *tag, const BitVector &BV) const;
 
   /// Removes all of the lifetime marker instructions from the function.
   /// \returns true if any markers were removed.
   bool removeAllMarkers();
 
   /// Scan the machine function and find all of the lifetime markers.
   /// Record the findings in the BEGIN and END vectors.
   /// \returns the number of markers found.

 };
 } // end anonymous namespace
 
 char StackColoring::ID = 0;
 char &llvm::StackColoringID = StackColoring::ID;
 
 INITIALIZE_PASS_BEGIN(StackColoring,
                    "stack-coloring", "Merge disjoint stack slots", false, false)
-INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
 INITIALIZE_PASS_DEPENDENCY(SlotIndexes)
 INITIALIZE_PASS_DEPENDENCY(StackProtector)
 INITIALIZE_PASS_END(StackColoring,
                    "stack-coloring", "Merge disjoint stack slots", false, false)
 
 void StackColoring::getAnalysisUsage(AnalysisUsage &AU) const {
-  AU.addRequired<MachineDominatorTree>();
-  AU.addPreserved<MachineDominatorTree>();
   AU.addRequired<SlotIndexes>();
   AU.addRequired<StackProtector>();
   MachineFunctionPass::getAnalysisUsage(AU);
 }
 
-LLVM_DUMP_METHOD void StackColoring::dump() const {
-  for (MachineBasicBlock *MBB : depth_first(MF)) {
-    DEBUG(dbgs() << "Inspecting block #" << BasicBlocks.lookup(MBB) << " ["
-                 << MBB->getName() << "]\n");
+LLVM_DUMP_METHOD void StackColoring::dumpBV(const char *tag, const BitVector &BV) const {
+  DEBUG(dbgs()<< tag << " : { ");
+  for (unsigned i=0; i < BV.size(); ++i)
+    DEBUG(dbgs()<<BV.test(i)<<" ");
+  DEBUG(dbgs()<<"}\n");
+}
 
-    LivenessMap::const_iterator BI = BlockLiveness.find(MBB);
-    assert(BI != BlockLiveness.end() && "Block not found");
-    const BlockLifetimeInfo &BlockInfo = BI->second;
+LLVM_DUMP_METHOD void StackColoring::dumpBB(MachineBasicBlock *MBB) const {
 
-    DEBUG(dbgs()<<"BEGIN  : {");
-    for (unsigned i=0; i < BlockInfo.Begin.size(); ++i)
-      DEBUG(dbgs()<<BlockInfo.Begin.test(i)<<" ");
-    DEBUG(dbgs()<<"}\n");
-
-    DEBUG(dbgs()<<"END    : {");
-    for (unsigned i=0; i < BlockInfo.End.size(); ++i)
-      DEBUG(dbgs()<<BlockInfo.End.test(i)<<" ");
-
-    DEBUG(dbgs()<<"}\n");
+  dumpBV("BEGIN", BlockInfo.Begin);
+  dumpBV("END", BlockInfo.End);
+  dumpBV("LIVE_IN", BlockInfo.LiveIn);
+  dumpBV("LIVE_OUT", BlockInfo.LiveOut);
+}
 
-    DEBUG(dbgs()<<"LIVE_IN: {");
-    for (unsigned i=0; i < BlockInfo.LiveIn.size(); ++i)
-      DEBUG(dbgs()<<BlockInfo.LiveIn.test(i)<<" ");
+LLVM_DUMP_METHOD void StackColoring::dump() const {
+  for (MachineBasicBlock *MBB : depth_first(MF)) {
+    DEBUG(dbgs() << "Inspecting block #" << MBB->getNumber() << " ["
+                 << MBB->getName() << "]\n");
+    dumpBB(MBB);
+  }
+}
 
-    DEBUG(dbgs()<<"}\n");
-    DEBUG(dbgs()<<"LIVEOUT: {");
-    for (unsigned i=0; i < BlockInfo.LiveOut.size(); ++i)
-      DEBUG(dbgs()<<BlockInfo.LiveOut.test(i)<<" ");
-    DEBUG(dbgs()<<"}\n");
+LLVM_DUMP_METHOD void StackColoring::dumpIntervals() const {
+  for (unsigned I = 0; I < Intervals.size(); ++I) {
+    DEBUG(dbgs() << "Interval[" << I << "]:\n");
+    Intervals[I]->dump();
   }
 }
 
 unsigned StackColoring::collectMarkers(unsigned NumSlot) {
   unsigned MarkersFound = 0;
   // Scan the function to find all lifetime markers.
   // NOTE: We use a reverse-post-order iteration to ensure that we obtain a
   // deterministic numbering, and because we'll need a post-order iteration