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/Transforms/Scalar/LoopDataPrefetch.cpp b/llvm/lib/Transforms/Scalar/LoopDataPrefetch.cpp
index c804115..3b41b5d 100644
--- a/llvm/lib/Transforms/Scalar/LoopDataPrefetch.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopDataPrefetch.cpp
@@ -244,9 +244,9 @@
   if (ItersAhead > getMaxPrefetchIterationsAhead())
     return MadeChange;
 
-  DEBUG(dbgs() << "Prefetching " << ItersAhead
-               << " iterations ahead (loop size: " << LoopSize << ") in "
-               << L->getHeader()->getParent()->getName() << ": " << *L);
+  LLVM_DEBUG(dbgs() << "Prefetching " << ItersAhead
+                    << " iterations ahead (loop size: " << LoopSize << ") in "
+                    << L->getHeader()->getParent()->getName() << ": " << *L);
 
   SmallVector<std::pair<Instruction *, const SCEVAddRecExpr *>, 16> PrefLoads;
   for (const auto BB : L->blocks()) {
@@ -320,8 +320,8 @@
            ConstantInt::get(I32, MemI->mayReadFromMemory() ? 0 : 1),
            ConstantInt::get(I32, 3), ConstantInt::get(I32, 1)});
       ++NumPrefetches;
-      DEBUG(dbgs() << "  Access: " << *PtrValue << ", SCEV: " << *LSCEV
-                   << "\n");
+      LLVM_DEBUG(dbgs() << "  Access: " << *PtrValue << ", SCEV: " << *LSCEV
+                        << "\n");
       ORE->emit([&]() {
         return OptimizationRemark(DEBUG_TYPE, "Prefetched", MemI)
                << "prefetched memory access";