[codeview] Make obj2yaml/yaml2obj support .debug$S/T sections.

This allows us to use yaml2obj and obj2yaml to round-trip CodeView
symbol and type information without having to manually specify the bytes
of the section. This makes for much easier to maintain tests. See the
tests under lld/COFF in this patch for example. Before they just said
SectionData: <blob> whereas now we can use meaningful record
descriptions. Note that it still supports the SectionData yaml field,
which could be useful for initializing a section to invalid bytes for
testing, for example.

Differential Revision: https://reviews.llvm.org/D34127

llvm-svn: 305366

1 files changed, 48 insertions, 0 deletions

diff --git a/llvm/lib/DebugInfo/CodeView/StringsAndChecksums.cpp b/llvm/lib/DebugInfo/CodeView/StringsAndChecksums.cpp
new file mode 100644
index 00000000000..ccd9aba45ea
--- /dev/null
+++ b/llvm/lib/DebugInfo/CodeView/StringsAndChecksums.cpp
@@ -0,0 +1,48 @@
+//===- StringsAndChecksums.cpp ----------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo/CodeView/StringsAndChecksums.h"
+#include "llvm/DebugInfo/CodeView/DebugChecksumsSubsection.h"
+#include "llvm/DebugInfo/CodeView/DebugStringTableSubsection.h"
+#include "llvm/DebugInfo/CodeView/DebugSubsectionRecord.h"
+
+using namespace llvm;
+using namespace llvm::codeview;
+
+StringsAndChecksumsRef::StringsAndChecksumsRef() {}
+
+StringsAndChecksumsRef::StringsAndChecksumsRef(
+    const DebugStringTableSubsectionRef &Strings)
+    : Strings(&Strings) {}
+
+StringsAndChecksumsRef::StringsAndChecksumsRef(
+    const DebugStringTableSubsectionRef &Strings,
+    const DebugChecksumsSubsectionRef &Checksums)
+    : Strings(&Strings), Checksums(&Checksums) {}
+
+void StringsAndChecksumsRef::initializeStrings(
+    const DebugSubsectionRecord &SR) {
+  assert(SR.kind() == DebugSubsectionKind::StringTable);
+  assert(!Strings && "Found a string table even though we already have one!");
+
+  OwnedStrings = llvm::make_unique<DebugStringTableSubsectionRef>();
+  consumeError(OwnedStrings->initialize(SR.getRecordData()));
+  Strings = OwnedStrings.get();
+}
+
+void StringsAndChecksumsRef::initializeChecksums(
+    const DebugSubsectionRecord &FCR) {
+  assert(FCR.kind() == DebugSubsectionKind::FileChecksums);
+  if (Checksums)
+    return;
+
+  OwnedChecksums = llvm::make_unique<DebugChecksumsSubsectionRef>();
+  consumeError(OwnedChecksums->initialize(FCR.getRecordData()));
+  Checksums = OwnedChecksums.get();
+}