Rename DEBUG macro to LLVM_DEBUG.
    
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.

In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.

Differential Revision: https://reviews.llvm.org/D43624

llvm-svn: 332240
diff --git a/llvm/lib/CodeGen/LazyMachineBlockFrequencyInfo.cpp b/llvm/lib/CodeGen/LazyMachineBlockFrequencyInfo.cpp
index 996d40c..5b52cc6 100644
--- a/llvm/lib/CodeGen/LazyMachineBlockFrequencyInfo.cpp
+++ b/llvm/lib/CodeGen/LazyMachineBlockFrequencyInfo.cpp
@@ -57,23 +57,23 @@
 LazyMachineBlockFrequencyInfoPass::calculateIfNotAvailable() const {
   auto *MBFI = getAnalysisIfAvailable<MachineBlockFrequencyInfo>();
   if (MBFI) {
-    DEBUG(dbgs() << "MachineBlockFrequencyInfo is available\n");
+    LLVM_DEBUG(dbgs() << "MachineBlockFrequencyInfo is available\n");
     return *MBFI;
   }
 
   auto &MBPI = getAnalysis<MachineBranchProbabilityInfo>();
   auto *MLI = getAnalysisIfAvailable<MachineLoopInfo>();
   auto *MDT = getAnalysisIfAvailable<MachineDominatorTree>();
-  DEBUG(dbgs() << "Building MachineBlockFrequencyInfo on the fly\n");
-  DEBUG(if (MLI) dbgs() << "LoopInfo is available\n");
+  LLVM_DEBUG(dbgs() << "Building MachineBlockFrequencyInfo on the fly\n");
+  LLVM_DEBUG(if (MLI) dbgs() << "LoopInfo is available\n");
 
   if (!MLI) {
-    DEBUG(dbgs() << "Building LoopInfo on the fly\n");
+    LLVM_DEBUG(dbgs() << "Building LoopInfo on the fly\n");
     // First create a dominator tree.
-    DEBUG(if (MDT) dbgs() << "DominatorTree is available\n");
+    LLVM_DEBUG(if (MDT) dbgs() << "DominatorTree is available\n");
 
     if (!MDT) {
-      DEBUG(dbgs() << "Building DominatorTree on the fly\n");
+      LLVM_DEBUG(dbgs() << "Building DominatorTree on the fly\n");
       OwnedMDT = make_unique<MachineDominatorTree>();
       OwnedMDT->getBase().recalculate(*MF);
       MDT = OwnedMDT.get();