IR: Give 'DI' prefix to debug info metadata

Finish off PR23080 by renaming the debug info IR constructs from `MD*`
to `DI*`.  The last of the `DIDescriptor` classes were deleted in
r235356, and the last of the related typedefs removed in r235413, so
this has all baked for about a week.

Note: If you have out-of-tree code (like a frontend), I recommend that
you get everything compiling and tests passing with the *previous*
commit before updating to this one.  It'll be easier to keep track of
what code is using the `DIDescriptor` hierarchy and what you've already
updated, and I think you're extremely unlikely to insert bugs.  YMMV of
course.

Back to *this* commit: I did this using the rename-md-di-nodes.sh
upgrade script I've attached to PR23080 (both code and testcases) and
filtered through clang-format-diff.py.  I edited the tests for
test/Assembler/invalid-generic-debug-node-*.ll by hand since the columns
were off-by-three.  It should work on your out-of-tree testcases (and
code, if you've followed the advice in the previous paragraph).

Some of the tests are in badly named files now (e.g.,
test/Assembler/invalid-mdcompositetype-missing-tag.ll should be
'dicompositetype'); I'll come back and move the files in a follow-up
commit.

llvm-svn: 236120

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/Scalar/ScalarReplAggregates.cpp b/llvm/lib/Transforms/Scalar/ScalarReplAggregates.cpp
index 5b47ef9d730..2ec1fd014aa 100644
--- a/llvm/lib/Transforms/Scalar/ScalarReplAggregates.cpp
+++ b/llvm/lib/Transforms/Scalar/ScalarReplAggregates.cpp
@@ -1060,8 +1060,8 @@ public:
     // Remember which alloca we're promoting (for isInstInList).
     this->AI = AI;
     if (auto *L = LocalAsMetadata::getIfExists(AI)) {
-      if (auto *DebugNode = MetadataAsValue::getIfExists(AI->getContext(), L)) {
-        for (User *U : DebugNode->users())
+      if (auto *DINode = MetadataAsValue::getIfExists(AI->getContext(), L)) {
+        for (User *U : DINode->users())
           if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(U))
             DDIs.push_back(DDI);
           else if (DbgValueInst *DVI = dyn_cast<DbgValueInst>(U))