[WebAssembly] Add COMDAT support

This adds COMDAT support to the Wasm object-file format.
Spec: https://github.com/WebAssembly/tool-conventions/pull/31

Corresponding LLD change:
https://bugs.llvm.org/show_bug.cgi?id=35533, and D40845

Patch by Nicholas Wilson

Differential Revision: https://reviews.llvm.org/D40844

llvm-svn: 322135

1 files changed, 21 insertions, 0 deletions

diff --git a/llvm/lib/ObjectYAML/WasmYAML.cpp b/llvm/lib/ObjectYAML/WasmYAML.cpp
index 70721e006da..4ae6dccccb1 100644
--- a/llvm/lib/ObjectYAML/WasmYAML.cpp
+++ b/llvm/lib/ObjectYAML/WasmYAML.cpp
@@ -61,6 +61,7 @@ static void sectionMapping(IO &IO, WasmYAML::LinkingSection &Section) {
   IO.mapOptional("SymbolInfo", Section.SymbolInfos);
   IO.mapOptional("SegmentInfo", Section.SegmentInfos);
   IO.mapOptional("InitFunctions", Section.InitFunctions);
+  IO.mapOptional("Comdats", Section.Comdats);
 }
 
 static void sectionMapping(IO &IO, WasmYAML::CustomSection &Section) {
@@ -368,6 +369,26 @@ void MappingTraits<WasmYAML::InitFunction>::mapping(
   IO.mapRequired("FunctionIndex", Init.FunctionIndex);
 }
 
+void ScalarEnumerationTraits<WasmYAML::ComdatKind>::enumeration(
+    IO &IO, WasmYAML::ComdatKind &Kind) {
+#define ECase(X) IO.enumCase(Kind, #X, wasm::WASM_COMDAT_##X);
+  ECase(FUNCTION);
+  ECase(DATA);
+#undef ECase
+}
+
+void MappingTraits<WasmYAML::ComdatEntry>::mapping(
+    IO &IO, WasmYAML::ComdatEntry &ComdatEntry) {
+  IO.mapRequired("Kind", ComdatEntry.Kind);
+  IO.mapRequired("Index", ComdatEntry.Index);
+}
+
+void MappingTraits<WasmYAML::Comdat>::mapping(
+    IO &IO, WasmYAML::Comdat &Comdat) {
+  IO.mapRequired("Name", Comdat.Name);
+  IO.mapRequired("Entries", Comdat.Entries);
+}
+
 void MappingTraits<WasmYAML::SymbolInfo>::mapping(IO &IO,
                                                   WasmYAML::SymbolInfo &Info) {
   IO.mapRequired("Name", Info.Name);