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/Analysis/MemorySSA.cpp b/llvm/lib/Analysis/MemorySSA.cpp
index 661922d..f2fd204 100644
--- a/llvm/lib/Analysis/MemorySSA.cpp
+++ b/llvm/lib/Analysis/MemorySSA.cpp
@@ -1240,10 +1240,11 @@
     unsigned long UpperBound = VersionStack.size() - 1;
 
     if (UpperBound - LocInfo.LowerBound > MaxCheckLimit) {
-      DEBUG(dbgs() << "MemorySSA skipping optimization of " << *MU << " ("
-                   << *(MU->getMemoryInst()) << ")"
-                   << " because there are " << UpperBound - LocInfo.LowerBound
-                   << " stores to disambiguate\n");
+      LLVM_DEBUG(dbgs() << "MemorySSA skipping optimization of " << *MU << " ("
+                        << *(MU->getMemoryInst()) << ")"
+                        << " because there are "
+                        << UpperBound - LocInfo.LowerBound
+                        << " stores to disambiguate\n");
       // Because we did not walk, LastKill is no longer valid, as this may
       // have been a kill.
       LocInfo.LastKillValid = false;
@@ -2036,10 +2037,10 @@
                                      : StartingUseOrDef;
 
   MemoryAccess *Clobber = getClobberingMemoryAccess(DefiningAccess, Q);
-  DEBUG(dbgs() << "Starting Memory SSA clobber for " << *I << " is ");
-  DEBUG(dbgs() << *StartingUseOrDef << "\n");
-  DEBUG(dbgs() << "Final Memory SSA clobber for " << *I << " is ");
-  DEBUG(dbgs() << *Clobber << "\n");
+  LLVM_DEBUG(dbgs() << "Starting Memory SSA clobber for " << *I << " is ");
+  LLVM_DEBUG(dbgs() << *StartingUseOrDef << "\n");
+  LLVM_DEBUG(dbgs() << "Final Memory SSA clobber for " << *I << " is ");
+  LLVM_DEBUG(dbgs() << *Clobber << "\n");
   return Clobber;
 }
 
@@ -2083,10 +2084,10 @@
   }
 
   MemoryAccess *Result = getClobberingMemoryAccess(DefiningAccess, Q);
-  DEBUG(dbgs() << "Starting Memory SSA clobber for " << *I << " is ");
-  DEBUG(dbgs() << *DefiningAccess << "\n");
-  DEBUG(dbgs() << "Final Memory SSA clobber for " << *I << " is ");
-  DEBUG(dbgs() << *Result << "\n");
+  LLVM_DEBUG(dbgs() << "Starting Memory SSA clobber for " << *I << " is ");
+  LLVM_DEBUG(dbgs() << *DefiningAccess << "\n");
+  LLVM_DEBUG(dbgs() << "Final Memory SSA clobber for " << *I << " is ");
+  LLVM_DEBUG(dbgs() << *Result << "\n");
 
   StartingAccess->setOptimized(Result);
   if (MSSA->isLiveOnEntryDef(Result))