Verifier: Check debug info intrinsic arguments

Verify that debug info intrinsic arguments are valid.  (These checks
will not recurse through the full debug info graph, so they don't need
to be cordoned of in `DebugInfoVerifier`.)

With those checks in place, changing the `DbgIntrinsicInst` accessors to
downcast to `MDLocalVariable` and `MDExpression` is natural (added isa
specializations in `Metadata.h` to support this).

Added tests to `test/Verifier` for the new -verify checks, and fixed the
debug info in all the in-tree tests.

If you have out-of-tree testcases that have started to fail to -verify,
hopefully the verify checks are helpful.  The most likely problem is
that the expression argument is `!{}` (instead of `!MDExpression()`).

llvm-svn: 232296

1 files changed, 24 insertions, 0 deletions

diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 1e1355000e8..f0071060276 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -329,6 +329,8 @@ private:
   void visitUserOp1(Instruction &I);
   void visitUserOp2(Instruction &I) { visitUserOp1(I); }
   void visitIntrinsicFunctionCall(Intrinsic::ID ID, CallInst &CI);
+  template <class DbgIntrinsicTy>
+  void visitDbgIntrinsic(StringRef Kind, DbgIntrinsicTy &DII);
   void visitAtomicCmpXchgInst(AtomicCmpXchgInst &CXI);
   void visitAtomicRMWInst(AtomicRMWInst &RMWI);
   void visitFenceInst(FenceInst &FI);
@@ -2798,6 +2800,10 @@ void Verifier::visitIntrinsicFunctionCall(Intrinsic::ID ID, CallInst &CI) {
   case Intrinsic::dbg_declare: // llvm.dbg.declare
     Assert(isa<MetadataAsValue>(CI.getArgOperand(0)),
            "invalid llvm.dbg.declare intrinsic call 1", &CI);
+    visitDbgIntrinsic("declare", cast<DbgDeclareInst>(CI));
+    break;
+  case Intrinsic::dbg_value: // llvm.dbg.value
+    visitDbgIntrinsic("value", cast<DbgValueInst>(CI));
     break;
   case Intrinsic::memcpy:
   case Intrinsic::memmove:
@@ -3012,6 +3018,24 @@ void Verifier::visitIntrinsicFunctionCall(Intrinsic::ID ID, CallInst &CI) {
   };
 }
 
+template <class DbgIntrinsicTy>
+void Verifier::visitDbgIntrinsic(StringRef Kind, DbgIntrinsicTy &DII) {
+  auto *MD = cast<MetadataAsValue>(DII.getArgOperand(0))->getMetadata();
+  Assert(isa<ValueAsMetadata>(MD) ||
+             (isa<MDNode>(MD) && !cast<MDNode>(MD)->getNumOperands()),
+         "invalid llvm.dbg." + Kind + " intrinsic address/value", &DII, MD);
+  Assert(isa<MDLocalVariable>(DII.getRawVariable()),
+         "invalid llvm.dbg." + Kind + " intrinsic variable", &DII,
+         DII.getRawVariable());
+  Assert(isa<MDExpression>(DII.getRawExpression()),
+         "invalid llvm.dbg." + Kind + " intrinsic expression", &DII,
+         DII.getRawExpression());
+
+  // Don't call visitMDNode(), since that will recurse through operands.
+  visitMDLocalVariable(*cast<MDLocalVariable>(DII.getVariable()));
+  visitMDExpression(*cast<MDExpression>(DII.getExpression()));
+}
+
 void DebugInfoVerifier::verifyDebugInfo() {
   if (!VerifyDebugInfo)
     return;