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/BreakFalseDeps.cpp b/llvm/lib/CodeGen/BreakFalseDeps.cpp
index 2e6d7275..7f098cb 100644
--- a/llvm/lib/CodeGen/BreakFalseDeps.cpp
+++ b/llvm/lib/CodeGen/BreakFalseDeps.cpp
@@ -165,13 +165,13 @@
   unsigned Pref) {
   unsigned reg = MI->getOperand(OpIdx).getReg();
   unsigned Clearance = RDA->getClearance(MI, reg);
-  DEBUG(dbgs() << "Clearance: " << Clearance << ", want " << Pref);
+  LLVM_DEBUG(dbgs() << "Clearance: " << Clearance << ", want " << Pref);
 
   if (Pref > Clearance) {
-    DEBUG(dbgs() << ": Break dependency.\n");
+    LLVM_DEBUG(dbgs() << ": Break dependency.\n");
     return true;
   }
-  DEBUG(dbgs() << ": OK .\n");
+  LLVM_DEBUG(dbgs() << ": OK .\n");
   return false;
 }
 
@@ -260,7 +260,7 @@
 
   RegClassInfo.runOnMachineFunction(mf);
 
-  DEBUG(dbgs() << "********** BREAK FALSE DEPENDENCIES **********\n");
+  LLVM_DEBUG(dbgs() << "********** BREAK FALSE DEPENDENCIES **********\n");
 
   // Traverse the basic blocks.
   for (MachineBasicBlock &MBB : mf) {