Allow VarStreamArray to use stateful extractors.

Previously extractors tried to be stateless with any additional
context information needed in order to parse items being passed
in via the extraction method.  This led to quite cumbersome
implementation challenges and awkwardness of use.  This patch
brings back support for stateful extractors, making the
implementation and usage simpler.

llvm-svn: 305093

5 files changed, 15 insertions, 16 deletions

diff --git a/llvm/lib/DebugInfo/CodeView/DebugChecksumsSubsection.cpp b/llvm/lib/DebugInfo/CodeView/DebugChecksumsSubsection.cpp
index 1a85a339f8c..c31b8d1c96d 100644
--- a/llvm/lib/DebugInfo/CodeView/DebugChecksumsSubsection.cpp
+++ b/llvm/lib/DebugInfo/CodeView/DebugChecksumsSubsection.cpp
@@ -25,8 +25,8 @@ struct FileChecksumEntryHeader {
                               // Checksum bytes follow.
 };
 
-Error llvm::VarStreamArrayExtractor<FileChecksumEntry>::extract(
-    BinaryStreamRef Stream, uint32_t &Len, FileChecksumEntry &Item) {
+Error llvm::VarStreamArrayExtractor<FileChecksumEntry>::
+operator()(BinaryStreamRef Stream, uint32_t &Len, FileChecksumEntry &Item) {
   BinaryStreamReader Reader(Stream);
 
   const FileChecksumEntryHeader *Header;
diff --git a/llvm/lib/DebugInfo/CodeView/DebugCrossImpSubsection.cpp b/llvm/lib/DebugInfo/CodeView/DebugCrossImpSubsection.cpp
index e0ceefcd5fa..2c4a0b77934 100644
--- a/llvm/lib/DebugInfo/CodeView/DebugCrossImpSubsection.cpp
+++ b/llvm/lib/DebugInfo/CodeView/DebugCrossImpSubsection.cpp
@@ -16,9 +16,9 @@ using namespace llvm;
 using namespace llvm::codeview;
 
 namespace llvm {
-Error VarStreamArrayExtractor<CrossModuleImportItem>::extract(
-    BinaryStreamRef Stream, uint32_t &Len,
-    codeview::CrossModuleImportItem &Item) {
+Error VarStreamArrayExtractor<CrossModuleImportItem>::
+operator()(BinaryStreamRef Stream, uint32_t &Len,
+           codeview::CrossModuleImportItem &Item) {
   BinaryStreamReader Reader(Stream);
   if (Reader.bytesRemaining() < sizeof(CrossModuleImport))
     return make_error<CodeViewError>(
diff --git a/llvm/lib/DebugInfo/CodeView/DebugInlineeLinesSubsection.cpp b/llvm/lib/DebugInfo/CodeView/DebugInlineeLinesSubsection.cpp
index 520a0ee4454..e7719d05dbd 100644
--- a/llvm/lib/DebugInfo/CodeView/DebugInlineeLinesSubsection.cpp
+++ b/llvm/lib/DebugInfo/CodeView/DebugInlineeLinesSubsection.cpp
@@ -17,9 +17,8 @@
 using namespace llvm;
 using namespace llvm::codeview;
 
-Error VarStreamArrayExtractor<InlineeSourceLine>::extract(
-    BinaryStreamRef Stream, uint32_t &Len, InlineeSourceLine &Item,
-    bool HasExtraFiles) {
+Error VarStreamArrayExtractor<InlineeSourceLine>::
+operator()(BinaryStreamRef Stream, uint32_t &Len, InlineeSourceLine &Item) {
   BinaryStreamReader Reader(Stream);
 
   if (auto EC = Reader.readObject(Item.Header))
@@ -44,8 +43,8 @@ Error DebugInlineeLinesSubsectionRef::initialize(BinaryStreamReader Reader) {
   if (auto EC = Reader.readEnum(Signature))
     return EC;
 
-  if (auto EC =
-          Reader.readArray(Lines, Reader.bytesRemaining(), hasExtraFiles()))
+  Lines.getExtractor().HasExtraFiles = hasExtraFiles();
+  if (auto EC = Reader.readArray(Lines, Reader.bytesRemaining()))
     return EC;
 
   assert(Reader.bytesRemaining() == 0);
diff --git a/llvm/lib/DebugInfo/CodeView/DebugLinesSubsection.cpp b/llvm/lib/DebugInfo/CodeView/DebugLinesSubsection.cpp
index 33a8f78beb3..fbcad61d60a 100644
--- a/llvm/lib/DebugInfo/CodeView/DebugLinesSubsection.cpp
+++ b/llvm/lib/DebugInfo/CodeView/DebugLinesSubsection.cpp
@@ -17,9 +17,8 @@
 using namespace llvm;
 using namespace llvm::codeview;
 
-Error LineColumnExtractor::extract(BinaryStreamRef Stream, uint32_t &Len,
-                                   LineColumnEntry &Item,
-                                   const LineFragmentHeader *Header) {
+Error LineColumnExtractor::operator()(BinaryStreamRef Stream, uint32_t &Len,
+                                      LineColumnEntry &Item) {
   using namespace codeview;
   const LineBlockFragmentHeader *BlockHeader;
   BinaryStreamReader Reader(Stream);
@@ -56,8 +55,8 @@ Error DebugLinesSubsectionRef::initialize(BinaryStreamReader Reader) {
   if (auto EC = Reader.readObject(Header))
     return EC;
 
-  if (auto EC =
-          Reader.readArray(LinesAndColumns, Reader.bytesRemaining(), Header))
+  LinesAndColumns.getExtractor().Header = Header;
+  if (auto EC = Reader.readArray(LinesAndColumns, Reader.bytesRemaining()))
     return EC;
 
   return Error::success();
diff --git a/llvm/lib/DebugInfo/CodeView/TypeTableCollection.cpp b/llvm/lib/DebugInfo/CodeView/TypeTableCollection.cpp
index 699694fde92..8d974d522f2 100644
--- a/llvm/lib/DebugInfo/CodeView/TypeTableCollection.cpp
+++ b/llvm/lib/DebugInfo/CodeView/TypeTableCollection.cpp
@@ -51,7 +51,8 @@ void TypeTableCollection::ensureTypeExists(TypeIndex Index) {
 
   CVType Type;
   uint32_t Len;
-  error(VarStreamArrayExtractor<CVType>::extract(Bytes, Len, Type));
+  VarStreamArrayExtractor<CVType> Extract;
+  error(Extract(Bytes, Len, Type));
 
   TypeDatabaseVisitor DBV(Database);
   error(codeview::visitTypeRecord(Type, Index, DBV));