Revert "Revert "DI: Fold constant arguments into a single MDString""

This reverts commit r218918, effectively reapplying r218914 after fixing
an Ocaml bindings test and an Asan crash.  The root cause of the latter
was a tightened-up check in `DILexicalBlock::Verify()`, so I'll file a
PR to investigate who requires the loose check (and why).

Original commit message follows.

--

This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString.  Integers are stringified and
a `\0` character is used as a separator.

Part of PR17891.

Note: I've attached my testcases upgrade scripts to the PR.  If I've
just broken your out-of-tree testcases, they might help.

llvm-svn: 219010

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
index b19b576cdf3..902dafa6f46 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -1713,7 +1713,7 @@ DIE *DwarfCompileUnit::getOrCreateGlobalVariableDIE(DIGlobalVariable GV) {
     // it is not a static member.
     if (!IsStaticMember)
       addConstantValue(*VariableDIE, CI, GTy);
-  } else if (const ConstantExpr *CE = getMergedGlobalExpr(GV->getOperand(11))) {
+  } else if (const ConstantExpr *CE = getMergedGlobalExpr(GV.getConstant())) {
     addToAccelTable = true;
     // GV is a merged global.
     DIELoc *Loc = new (DIEValueAllocator) DIELoc();