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/InstCombineCasts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
index 1613677..f01bfca 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
@@ -697,8 +697,10 @@
 
     // If this cast is a truncate, evaluting in a different type always
     // eliminates the cast, so it is always a win.
-    DEBUG(dbgs() << "ICE: EvaluateInDifferentType converting expression type"
-          " to avoid cast: " << CI << '\n');
+    LLVM_DEBUG(
+        dbgs() << "ICE: EvaluateInDifferentType converting expression type"
+                  " to avoid cast: "
+               << CI << '\n');
     Value *Res = EvaluateInDifferentType(Src, DestTy, false);
     assert(Res->getType() == DestTy);
     return replaceInstUsesWith(CI, Res);
@@ -1070,8 +1072,10 @@
            "Can't clear more bits than in SrcTy");
 
     // Okay, we can transform this!  Insert the new expression now.
-    DEBUG(dbgs() << "ICE: EvaluateInDifferentType converting expression type"
-          " to avoid zero extend: " << CI << '\n');
+    LLVM_DEBUG(
+        dbgs() << "ICE: EvaluateInDifferentType converting expression type"
+                  " to avoid zero extend: "
+               << CI << '\n');
     Value *Res = EvaluateInDifferentType(Src, DestTy, false);
     assert(Res->getType() == DestTy);
 
@@ -1344,8 +1348,10 @@
   if ((DestTy->isVectorTy() || shouldChangeType(SrcTy, DestTy)) &&
       canEvaluateSExtd(Src, DestTy)) {
     // Okay, we can transform this!  Insert the new expression now.
-    DEBUG(dbgs() << "ICE: EvaluateInDifferentType converting expression type"
-          " to avoid sign extend: " << CI << '\n');
+    LLVM_DEBUG(
+        dbgs() << "ICE: EvaluateInDifferentType converting expression type"
+                  " to avoid sign extend: "
+               << CI << '\n');
     Value *Res = EvaluateInDifferentType(Src, DestTy, true);
     assert(Res->getType() == DestTy);