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/Target/Hexagon/HexagonBranchRelaxation.cpp b/llvm/lib/Target/Hexagon/HexagonBranchRelaxation.cpp
index 3e6420c..2fa7888 100644
--- a/llvm/lib/Target/Hexagon/HexagonBranchRelaxation.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonBranchRelaxation.cpp
@@ -90,7 +90,7 @@
 }
 
 bool HexagonBranchRelaxation::runOnMachineFunction(MachineFunction &MF) {
-  DEBUG(dbgs() << "****** Hexagon Branch Relaxation ******\n");
+  LLVM_DEBUG(dbgs() << "****** Hexagon Branch Relaxation ******\n");
 
   auto &HST = MF.getSubtarget<HexagonSubtarget>();
   HII = HST.getInstrInfo();
@@ -200,14 +200,14 @@
     for (auto &MI : B) {
       if (!MI.isBranch() || !isJumpOutOfRange(MI, BlockToInstOffset))
         continue;
-      DEBUG(dbgs() << "Long distance jump. isExtendable("
-                   << HII->isExtendable(MI) << ") isConstExtended("
-                   << HII->isConstExtended(MI) << ") " << MI);
+      LLVM_DEBUG(dbgs() << "Long distance jump. isExtendable("
+                        << HII->isExtendable(MI) << ") isConstExtended("
+                        << HII->isConstExtended(MI) << ") " << MI);
 
       // Since we have not merged HW loops relaxation into
       // this code (yet), soften our approach for the moment.
       if (!HII->isExtendable(MI) && !HII->isExtended(MI)) {
-        DEBUG(dbgs() << "\tUnderimplemented relax branch instruction.\n");
+        LLVM_DEBUG(dbgs() << "\tUnderimplemented relax branch instruction.\n");
       } else {
         // Find which operand is expandable.
         int ExtOpNum = HII->getCExtOpNum(MI);