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/InstCombine/InstCombinePHI.cpp b/llvm/lib/Transforms/InstCombine/InstCombinePHI.cpp
index 0827a34..91850ce 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombinePHI.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombinePHI.cpp
@@ -1008,10 +1008,9 @@
   // extracted out of it.  First, sort the users by their offset and size.
   array_pod_sort(PHIUsers.begin(), PHIUsers.end());
 
-  DEBUG(dbgs() << "SLICING UP PHI: " << FirstPhi << '\n';
-        for (unsigned i = 1, e = PHIsToSlice.size(); i != e; ++i)
-          dbgs() << "AND USER PHI #" << i << ": " << *PHIsToSlice[i] << '\n';
-    );
+  LLVM_DEBUG(dbgs() << "SLICING UP PHI: " << FirstPhi << '\n';
+             for (unsigned i = 1, e = PHIsToSlice.size(); i != e; ++i) dbgs()
+             << "AND USER PHI #" << i << ": " << *PHIsToSlice[i] << '\n';);
 
   // PredValues - This is a temporary used when rewriting PHI nodes.  It is
   // hoisted out here to avoid construction/destruction thrashing.
@@ -1092,8 +1091,8 @@
       }
       PredValues.clear();
 
-      DEBUG(dbgs() << "  Made element PHI for offset " << Offset << ": "
-                   << *EltPHI << '\n');
+      LLVM_DEBUG(dbgs() << "  Made element PHI for offset " << Offset << ": "
+                        << *EltPHI << '\n');
       ExtractedVals[LoweredPHIRecord(PN, Offset, Ty)] = EltPHI;
     }