[codeview] Add TypeVisitorCallbackPipeline.

We were kind of hacking this together before by embedding the
ability to forward requests into the TypeDeserializer.  When
we want to start adding more different kinds of visitor callback
interfaces though, this doesn't scale well and is very inflexible.

So introduce the notion of a pipeline, which itself implements
the TypeVisitorCallbacks interface, but which contains an internal
list of other callbacks to invoke in sequence.

Also update the existing uses of CVTypeVisitor to use this new
pipeline class for deserializing records before visiting them
with another visitor.

llvm-svn: 280293

7 files changed, 149 insertions, 31 deletions

diff --git a/llvm/include/llvm/DebugInfo/CodeView/TypeDeserializer.h b/llvm/include/llvm/DebugInfo/CodeView/TypeDeserializer.h
index e3ab75440bc..27d9e596132 100644
--- a/llvm/include/llvm/DebugInfo/CodeView/TypeDeserializer.h
+++ b/llvm/include/llvm/DebugInfo/CodeView/TypeDeserializer.h
@@ -17,16 +17,7 @@ namespace llvm {
 namespace codeview {
 class TypeDeserializer : public TypeVisitorCallbacks {
 public:
-  explicit TypeDeserializer(TypeVisitorCallbacks &Recipient)
-      : Recipient(Recipient) {}
-
-  Error visitTypeBegin(const CVRecord<TypeLeafKind> &Record) override {
-    return Recipient.visitTypeBegin(Record);
-  }
-
-  Error visitTypeEnd(const CVRecord<TypeLeafKind> &Record) override {
-    return Recipient.visitTypeEnd(Record);
-  }
+  TypeDeserializer() {}
 
 #define TYPE_RECORD(EnumName, EnumVal, Name)                                   \
   Error visitKnownRecord(const CVRecord<TypeLeafKind> &CVR,                    \
@@ -40,7 +31,6 @@ public:
 #include "TypeRecords.def"
 
 protected:
-  TypeVisitorCallbacks &Recipient;
 
   template <typename T>
   Error deserializeRecord(ArrayRef<uint8_t> &Data, TypeLeafKind Kind,
@@ -59,7 +49,7 @@ private:
     ArrayRef<uint8_t> RD = CVR.Data;
     if (auto EC = deserializeRecord(RD, CVR.Type, Record))
       return EC;
-    return Recipient.visitKnownRecord(CVR, Record);
+    return Error::success();
   }
 };
 }
diff --git a/llvm/include/llvm/DebugInfo/CodeView/TypeVisitorCallbackPipeline.h b/llvm/include/llvm/DebugInfo/CodeView/TypeVisitorCallbackPipeline.h
new file mode 100644
index 00000000000..3bfd52d4da4
--- /dev/null
+++ b/llvm/include/llvm/DebugInfo/CodeView/TypeVisitorCallbackPipeline.h
@@ -0,0 +1,83 @@
+//===- TypeVisitorCallbackPipeline.h -------------------------- *- C++ --*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_DEBUGINFO_CODEVIEW_TYPEVISITORCALLBACKPIPELINE_H
+#define LLVM_DEBUGINFO_CODEVIEW_TYPEVISITORCALLBACKPIPELINE_H
+
+#include "llvm/DebugInfo/CodeView/CodeView.h"
+#include "llvm/DebugInfo/CodeView/TypeRecord.h"
+#include "llvm/DebugInfo/CodeView/TypeVisitorCallbacks.h"
+
+#include <vector>
+
+namespace llvm {
+namespace codeview {
+class TypeVisitorCallbackPipeline : public TypeVisitorCallbacks {
+public:
+  TypeVisitorCallbackPipeline() {}
+
+  virtual Error
+  visitUnknownType(const CVRecord<TypeLeafKind> &Record) override {
+    for (auto Visitor : Pipeline) {
+      if (auto EC = Visitor->visitUnknownType(Record))
+        return EC;
+    }
+    return Error::success();
+  }
+
+  virtual Error
+  visitUnknownMember(const CVRecord<TypeLeafKind> &Record) override {
+    for (auto Visitor : Pipeline) {
+      if (auto EC = Visitor->visitUnknownMember(Record))
+        return EC;
+    }
+    return Error::success();
+  }
+
+  virtual Error visitTypeBegin(const CVRecord<TypeLeafKind> &Record) override {
+    for (auto Visitor : Pipeline) {
+      if (auto EC = Visitor->visitTypeBegin(Record))
+        return EC;
+    }
+    return Error::success();
+  }
+  virtual Error visitTypeEnd(const CVRecord<TypeLeafKind> &Record) override {
+    for (auto Visitor : Pipeline) {
+      if (auto EC = Visitor->visitTypeEnd(Record))
+        return EC;
+    }
+    return Error::success();
+  }
+
+  void addCallbackToPipeline(TypeVisitorCallbacks &Callbacks) {
+    Pipeline.push_back(&Callbacks);
+  }
+
+#define TYPE_RECORD(EnumName, EnumVal, Name)                                   \
+  Error visitKnownRecord(const CVRecord<TypeLeafKind> &CVR,                    \
+                         Name##Record &Record) override {                      \
+    for (auto Visitor : Pipeline) {                                            \
+      if (auto EC = Visitor->visitKnownRecord(CVR, Record))                    \
+        return EC;                                                             \
+    }                                                                          \
+    return Error::success();                                                   \
+  }
+#define MEMBER_RECORD(EnumName, EnumVal, Name)                                 \
+  TYPE_RECORD(EnumName, EnumVal, Name)
+#define TYPE_RECORD_ALIAS(EnumName, EnumVal, Name, AliasName)
+#define MEMBER_RECORD_ALIAS(EnumName, EnumVal, Name, AliasName)
+#include "llvm/DebugInfo/CodeView/TypeRecords.def"
+
+private:
+  std::vector<TypeVisitorCallbacks *> Pipeline;
+};
+}
+}
+
+#endif
diff --git a/llvm/lib/DebugInfo/CodeView/TypeDumper.cpp b/llvm/lib/DebugInfo/CodeView/TypeDumper.cpp
index 23788205fcf..f7dfdd2f398 100644
--- a/llvm/lib/DebugInfo/CodeView/TypeDumper.cpp
+++ b/llvm/lib/DebugInfo/CodeView/TypeDumper.cpp
@@ -13,6 +13,7 @@
 #include "llvm/DebugInfo/CodeView/TypeDeserializer.h"
 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
 #include "llvm/DebugInfo/CodeView/TypeRecord.h"
+#include "llvm/DebugInfo/CodeView/TypeVisitorCallbackPipeline.h"
 #include "llvm/DebugInfo/MSF/ByteStream.h"
 #include "llvm/Support/ScopedPrinter.h"
 
@@ -249,8 +250,12 @@ Error CVTypeDumper::visitTypeEnd(const CVRecord<TypeLeafKind> &Record) {
 
 Error CVTypeDumper::visitKnownRecord(const CVRecord<TypeLeafKind> &CVR,
                                      FieldListRecord &FieldList) {
-  TypeDeserializer Deserializer(*this);
-  CVTypeVisitor Visitor(Deserializer);
+  TypeDeserializer Deserializer;
+  TypeVisitorCallbackPipeline Pipeline;
+  Pipeline.addCallbackToPipeline(Deserializer);
+  Pipeline.addCallbackToPipeline(*this);
+
+  CVTypeVisitor Visitor(Pipeline);
   if (auto EC = Visitor.visitFieldListMemberStream(FieldList.Data))
     return EC;
 
@@ -711,8 +716,12 @@ void CVTypeDumper::printTypeIndex(StringRef FieldName, TypeIndex TI) {
 
 Error CVTypeDumper::dump(const CVRecord<TypeLeafKind> &Record) {
   assert(W && "printer should not be null");
-  TypeDeserializer Deserializer(*this);
-  CVTypeVisitor Visitor(Deserializer);
+  TypeDeserializer Deserializer;
+  TypeVisitorCallbackPipeline Pipeline;
+  Pipeline.addCallbackToPipeline(Deserializer);
+  Pipeline.addCallbackToPipeline(*this);
+
+  CVTypeVisitor Visitor(Pipeline);
 
   if (auto EC = Visitor.visitTypeRecord(Record))
     return EC;
@@ -721,8 +730,12 @@ Error CVTypeDumper::dump(const CVRecord<TypeLeafKind> &Record) {
 
 Error CVTypeDumper::dump(const CVTypeArray &Types) {
   assert(W && "printer should not be null");
-  TypeDeserializer Deserializer(*this);
-  CVTypeVisitor Visitor(Deserializer);
+  TypeDeserializer Deserializer;
+  TypeVisitorCallbackPipeline Pipeline;
+  Pipeline.addCallbackToPipeline(Deserializer);
+  Pipeline.addCallbackToPipeline(*this);
+
+  CVTypeVisitor Visitor(Pipeline);
 
   if (auto EC = Visitor.visitTypeStream(Types))
     return EC;
diff --git a/llvm/lib/DebugInfo/CodeView/TypeStreamMerger.cpp b/llvm/lib/DebugInfo/CodeView/TypeStreamMerger.cpp
index 0ce20623d1d..ddc3f4af58e 100644
--- a/llvm/lib/DebugInfo/CodeView/TypeStreamMerger.cpp
+++ b/llvm/lib/DebugInfo/CodeView/TypeStreamMerger.cpp
@@ -15,6 +15,7 @@
 #include "llvm/DebugInfo/CodeView/TypeDeserializer.h"
 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
 #include "llvm/DebugInfo/CodeView/TypeRecord.h"
+#include "llvm/DebugInfo/CodeView/TypeVisitorCallbackPipeline.h"
 #include "llvm/DebugInfo/CodeView/TypeVisitorCallbacks.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/ScopedPrinter.h"
@@ -84,8 +85,13 @@ private:
 
   Error visitKnownRecordImpl(FieldListRecord &Record) {
     // Don't do anything, this will get written in the call to visitTypeEnd().
-    TypeDeserializer Deserializer(*this);
-    CVTypeVisitor Visitor(Deserializer);
+    TypeVisitorCallbackPipeline Pipeline;
+    TypeDeserializer Deserializer;
+
+    Pipeline.addCallbackToPipeline(Deserializer);
+    Pipeline.addCallbackToPipeline(*this);
+
+    CVTypeVisitor Visitor(Pipeline);
 
     if (auto EC = Visitor.visitFieldListMemberStream(Record.Data))
       return EC;
@@ -160,8 +166,13 @@ Error TypeStreamMerger::visitUnknownType(const CVRecord<TypeLeafKind> &Rec) {
 
 bool TypeStreamMerger::mergeStream(const CVTypeArray &Types) {
   assert(IndexMap.empty());
-  TypeDeserializer Deserializer(*this);
-  CVTypeVisitor Visitor(Deserializer);
+  TypeVisitorCallbackPipeline Pipeline;
+
+  TypeDeserializer Deserializer;
+  Pipeline.addCallbackToPipeline(Deserializer);
+  Pipeline.addCallbackToPipeline(*this);
+
+  CVTypeVisitor Visitor(Pipeline);
 
   if (auto EC = Visitor.visitTypeStream(Types)) {
     consumeError(std::move(EC));
diff --git a/llvm/lib/DebugInfo/PDB/Raw/TpiStream.cpp b/llvm/lib/DebugInfo/PDB/Raw/TpiStream.cpp
index 424ef0ef441..74200e70119 100644
--- a/llvm/lib/DebugInfo/PDB/Raw/TpiStream.cpp
+++ b/llvm/lib/DebugInfo/PDB/Raw/TpiStream.cpp
@@ -14,6 +14,7 @@
 #include "llvm/DebugInfo/CodeView/TypeDeserializer.h"
 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
 #include "llvm/DebugInfo/CodeView/TypeRecord.h"
+#include "llvm/DebugInfo/CodeView/TypeVisitorCallbackPipeline.h"
 #include "llvm/DebugInfo/MSF/MappedBlockStream.h"
 #include "llvm/DebugInfo/MSF/StreamReader.h"
 #include "llvm/DebugInfo/PDB/Raw/Hash.h"
@@ -160,8 +161,13 @@ private:
 // Currently we only verify SRC_LINE records.
 Error TpiStream::verifyHashValues() {
   TpiHashVerifier Verifier(HashValues, Header->NumHashBuckets);
-  TypeDeserializer Deserializer(Verifier);
-  CVTypeVisitor Visitor(Deserializer);
+  TypeDeserializer Deserializer;
+
+  TypeVisitorCallbackPipeline Pipeline;
+  Pipeline.addCallbackToPipeline(Deserializer);
+  Pipeline.addCallbackToPipeline(Verifier);
+
+  CVTypeVisitor Visitor(Pipeline);
   return Visitor.visitTypeStream(TypeRecords);
 }
 
diff --git a/llvm/tools/llvm-pdbdump/CodeViewYaml.cpp b/llvm/tools/llvm-pdbdump/CodeViewYaml.cpp
index 690e46fb041..96bf1c19aa6 100644
--- a/llvm/tools/llvm-pdbdump/CodeViewYaml.cpp
+++ b/llvm/tools/llvm-pdbdump/CodeViewYaml.cpp
@@ -13,6 +13,7 @@
 #include "llvm/DebugInfo/CodeView/EnumTables.h"
 #include "llvm/DebugInfo/CodeView/TypeDeserializer.h"
 #include "llvm/DebugInfo/CodeView/TypeRecord.h"
+#include "llvm/DebugInfo/CodeView/TypeVisitorCallbackPipeline.h"
 
 using namespace llvm;
 using namespace llvm::codeview;
@@ -240,10 +241,14 @@ template <> struct ScalarTraits<APSInt> {
 
 void MappingTraits<CVType>::mapping(IO &IO, CVType &Record) {
   if (IO.outputting()) {
+    codeview::TypeDeserializer Deserializer;
     codeview::yaml::YamlTypeDumperCallbacks Callbacks(IO);
-    codeview::TypeDeserializer Deserializer(Callbacks);
 
-    codeview::CVTypeVisitor Visitor(Deserializer);
+    codeview::TypeVisitorCallbackPipeline Pipeline;
+    Pipeline.addCallbackToPipeline(Deserializer);
+    Pipeline.addCallbackToPipeline(Callbacks);
+
+    codeview::CVTypeVisitor Visitor(Pipeline);
     consumeError(Visitor.visitTypeRecord(Record));
   }
 }
@@ -252,8 +257,13 @@ void MappingTraits<FieldListRecord>::mapping(IO &IO,
                                              FieldListRecord &FieldList) {
   if (IO.outputting()) {
     codeview::yaml::YamlTypeDumperCallbacks Callbacks(IO);
-    codeview::TypeDeserializer Deserializer(Callbacks);
-    codeview::CVTypeVisitor Visitor(Deserializer);
+    codeview::TypeDeserializer Deserializer;
+
+    codeview::TypeVisitorCallbackPipeline Pipeline;
+    Pipeline.addCallbackToPipeline(Deserializer);
+    Pipeline.addCallbackToPipeline(Callbacks);
+
+    codeview::CVTypeVisitor Visitor(Pipeline);
     consumeError(Visitor.visitFieldListMemberStream(FieldList.Data));
   }
 }
diff --git a/llvm/tools/llvm-pdbdump/PdbYaml.cpp b/llvm/tools/llvm-pdbdump/PdbYaml.cpp
index 187264acdbe..566d6b89986 100644
--- a/llvm/tools/llvm-pdbdump/PdbYaml.cpp
+++ b/llvm/tools/llvm-pdbdump/PdbYaml.cpp
@@ -8,10 +8,12 @@
 //===----------------------------------------------------------------------===//
 
 #include "PdbYaml.h"
+
 #include "CodeViewYaml.h"
 
 #include "llvm/DebugInfo/CodeView/CVTypeVisitor.h"
 #include "llvm/DebugInfo/CodeView/TypeDeserializer.h"
+#include "llvm/DebugInfo/CodeView/TypeVisitorCallbackPipeline.h"
 #include "llvm/DebugInfo/PDB/PDBExtras.h"
 #include "llvm/DebugInfo/PDB/PDBTypes.h"
 #include "llvm/DebugInfo/PDB/Raw/PDBFile.h"
@@ -200,11 +202,14 @@ void MappingTraits<PdbDbiModuleInfo>::mapping(IO &IO, PdbDbiModuleInfo &Obj) {
 void MappingTraits<PdbTpiRecord>::mapping(IO &IO,
                                           pdb::yaml::PdbTpiRecord &Obj) {
   if (IO.outputting()) {
-    // If we're going from Pdb To Yaml, deserialize the Pdb record
+    codeview::TypeDeserializer Deserializer;
     codeview::yaml::YamlTypeDumperCallbacks Callbacks(IO);
-    codeview::TypeDeserializer Deserializer(Callbacks);
 
-    codeview::CVTypeVisitor Visitor(Deserializer);
+    codeview::TypeVisitorCallbackPipeline Pipeline;
+    Pipeline.addCallbackToPipeline(Deserializer);
+    Pipeline.addCallbackToPipeline(Callbacks);
+
+    codeview::CVTypeVisitor Visitor(Pipeline);
     consumeError(Visitor.visitTypeRecord(Obj.Record));
   } else {
     codeview::yaml::YamlTypeDumperCallbacks Callbacks(IO);