Verifier: Move checks over from DIDescriptor::Verify()

Move over some more checks from `DIDescriptor::Verify()`, and change
`LLParser` to require non-null `file:` fields in compile units.

I've ignored the comment in test/Assembler/metadata-null-operands.ll
since I disagree with it.  At the time that test was written (r229960),
the debug info verifier wasn't on by default, so my comment there is in
the context of not expecting the verifier to be useful.  It is now, and
besides that, since r233394 we can check when parsing textual IR whether
an operand is null that shouldn't be.

llvm-svn: 233654

2 files changed, 36 insertions, 56 deletions

diff --git a/llvm/lib/IR/DebugInfo.cpp b/llvm/lib/IR/DebugInfo.cpp
index bc40907ba18..4e5b5f1f975 100644
--- a/llvm/lib/IR/DebugInfo.cpp
+++ b/llvm/lib/IR/DebugInfo.cpp
@@ -220,15 +220,7 @@ void DIDescriptor::replaceAllUsesWith(MDNode *D) {
   Node->replaceAllUsesWith(D);
 }
 
-bool DICompileUnit::Verify() const {
-  if (!isCompileUnit())
-    return false;
-
-  // Don't bother verifying the compilation directory or producer string
-  // as those could be empty.
-  return !getFilename().empty();
-}
-
+bool DICompileUnit::Verify() const { return isCompileUnit(); }
 bool DIObjCProperty::Verify() const { return isObjCProperty(); }
 
 /// \brief Check if a value can be a reference to a type.
@@ -264,61 +256,18 @@ bool DIType::Verify() const {
   auto *N = dyn_cast_or_null<MDType>(DbgNode);
   if (!N)
     return false;
-  if (!isScopeRef(N->getScope()))
-    return false;
-
-  // DIType is abstract, it should be a BasicType, a DerivedType or
-  // a CompositeType.
-  if (isBasicType())
-    return DIBasicType(DbgNode).Verify();
-
-  // FIXME: Sink this into the various subclass verifies.
-  if (getFilename().empty()) {
-    // Check whether the filename is allowed to be empty.
-    uint16_t Tag = getTag();
-    if (Tag != dwarf::DW_TAG_const_type && Tag != dwarf::DW_TAG_volatile_type &&
-        Tag != dwarf::DW_TAG_pointer_type &&
-        Tag != dwarf::DW_TAG_ptr_to_member_type &&
-        Tag != dwarf::DW_TAG_reference_type &&
-        Tag != dwarf::DW_TAG_rvalue_reference_type &&
-        Tag != dwarf::DW_TAG_restrict_type && Tag != dwarf::DW_TAG_array_type &&
-        Tag != dwarf::DW_TAG_enumeration_type &&
-        Tag != dwarf::DW_TAG_subroutine_type &&
-        Tag != dwarf::DW_TAG_inheritance && Tag != dwarf::DW_TAG_friend &&
-        Tag != dwarf::DW_TAG_structure_type && Tag != dwarf::DW_TAG_member &&
-        Tag != dwarf::DW_TAG_typedef)
-      return false;
-  }
 
   if (isCompositeType())
     return DICompositeType(DbgNode).Verify();
-  if (isDerivedType())
-    return DIDerivedType(DbgNode).Verify();
-  return false;
-}
-
-bool DIBasicType::Verify() const {
-  return dyn_cast_or_null<MDBasicType>(DbgNode);
+  return true;
 }
 
-bool DIDerivedType::Verify() const {
-  auto *N = dyn_cast_or_null<MDDerivedTypeBase>(DbgNode);
-  if (!N)
-    return false;
-  if (getTag() == dwarf::DW_TAG_ptr_to_member_type) {
-    auto *D = dyn_cast<MDDerivedType>(N);
-    if (!D)
-      return false;
-    if (!isTypeRef(D->getExtraData()))
-      return false;
-  }
-  return isTypeRef(N->getBaseType());
-}
+bool DIBasicType::Verify() const { return isBasicType(); }
+bool DIDerivedType::Verify() const { return isDerivedType(); }
 
 bool DICompositeType::Verify() const {
   auto *N = dyn_cast_or_null<MDCompositeTypeBase>(DbgNode);
-  return N && isTypeRef(N->getBaseType()) && isTypeRef(N->getVTableHolder()) &&
-         !(isLValueReference() && isRValueReference());
+  return N && !(isLValueReference() && isRValueReference());
 }
 
 bool DISubprogram::Verify() const {
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index e5488593b8f..4bf24211963 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -752,6 +752,26 @@ void Verifier::visitMDDerivedTypeBase(const MDDerivedTypeBase &N) {
 
   Assert(isScopeRef(N.getScope()), "invalid scope", &N, N.getScope());
   Assert(isTypeRef(N.getBaseType()), "invalid base type", &N, N.getBaseType());
+
+  // FIXME: Sink this into the subclass verifies.
+  if (!N.getFile() || N.getFile()->getFilename().empty()) {
+    // Check whether the filename is allowed to be empty.
+    uint16_t Tag = N.getTag();
+    Assert(
+        Tag == dwarf::DW_TAG_const_type || Tag == dwarf::DW_TAG_volatile_type ||
+            Tag == dwarf::DW_TAG_pointer_type ||
+            Tag == dwarf::DW_TAG_ptr_to_member_type ||
+            Tag == dwarf::DW_TAG_reference_type ||
+            Tag == dwarf::DW_TAG_rvalue_reference_type ||
+            Tag == dwarf::DW_TAG_restrict_type ||
+            Tag == dwarf::DW_TAG_array_type ||
+            Tag == dwarf::DW_TAG_enumeration_type ||
+            Tag == dwarf::DW_TAG_subroutine_type ||
+            Tag == dwarf::DW_TAG_inheritance || Tag == dwarf::DW_TAG_friend ||
+            Tag == dwarf::DW_TAG_structure_type ||
+            Tag == dwarf::DW_TAG_member || Tag == dwarf::DW_TAG_typedef,
+        "derived/composite type requires a filename", &N, N.getFile());
+  }
 }
 
 void Verifier::visitMDDerivedType(const MDDerivedType &N) {
@@ -770,6 +790,10 @@ void Verifier::visitMDDerivedType(const MDDerivedType &N) {
              N.getTag() == dwarf::DW_TAG_inheritance ||
              N.getTag() == dwarf::DW_TAG_friend,
          "invalid tag", &N);
+  if (N.getTag() == dwarf::DW_TAG_ptr_to_member_type) {
+    Assert(isTypeRef(N.getExtraData()), "invalid pointer to member type",
+           &N, N.getExtraData());
+  }
 }
 
 void Verifier::visitMDCompositeType(const MDCompositeType &N) {
@@ -809,6 +833,13 @@ void Verifier::visitMDFile(const MDFile &N) {
 void Verifier::visitMDCompileUnit(const MDCompileUnit &N) {
   Assert(N.getTag() == dwarf::DW_TAG_compile_unit, "invalid tag", &N);
 
+  // Don't bother verifying the compilation directory or producer string
+  // as those could be empty.
+  Assert(N.getRawFile() && isa<MDFile>(N.getRawFile()),
+         "invalid file", &N, N.getRawFile());
+  Assert(!N.getFile()->getFilename().empty(), "invalid filename", &N,
+         N.getFile());
+
   if (auto *Array = N.getRawEnumTypes()) {
     Assert(isa<MDTuple>(Array), "invalid enum list", &N, Array);
     for (Metadata *Op : N.getEnumTypes()->operands()) {