Verifier: Check accessors of MDLocation

Check accessors of `MDLocation`, and change them to `cast<>` down to the
right types.  Also add type-safe factory functions.

All the callers that handle broken code need to use the new versions of
the accessors (`getRawScope()` instead of `getScope()`) that still
return `Metadata*`.  This is also necessary for things like
`MDNodeKeyImpl<MDLocation>` (in LLVMContextImpl.h) that need to unique
the nodes when their operands might still be forward references of the
wrong type.

In the `Value` hierarchy, consumers that handle broken code use
`getOperand()` directly.  However, debug info nodes have a ton of
operands, and their order (even their existence) isn't stable yet.  It's
safer and more maintainable to add an explicit "raw" accessor on the
class itself.

llvm-svn: 233322

1 files changed, 3 insertions, 4 deletions

diff --git a/llvm/lib/IR/AsmWriter.cpp b/llvm/lib/IR/AsmWriter.cpp
index 4eba3212e2b..d77c3447705 100644
--- a/llvm/lib/IR/AsmWriter.cpp
+++ b/llvm/lib/IR/AsmWriter.cpp
@@ -1419,11 +1419,10 @@ static void writeMDLocation(raw_ostream &Out, const MDLocation *DL,
   if (DL->getColumn())
     Out << FS << "column: " << DL->getColumn();
   Out << FS << "scope: ";
-  WriteAsOperandInternal(Out, DL->getScope(), TypePrinter, Machine, Context);
-  if (DL->getInlinedAt()) {
+  WriteAsOperandInternal(Out, DL->getRawScope(), TypePrinter, Machine, Context);
+  if (auto *IA = DL->getRawInlinedAt()) {
     Out << FS << "inlinedAt: ";
-    WriteAsOperandInternal(Out, DL->getInlinedAt(), TypePrinter, Machine,
-                           Context);
+    WriteAsOperandInternal(Out, IA, TypePrinter, Machine, Context);
   }
   Out << ")";
 }