[WebAssembly] Add support for init functions linking metadata

Summary:
This change lays the groundwork lowering of @llvm.global_ctors
and @llvm.global_dtors for the wasm object format.  Some parts
of this patch are subset of: https://reviews.llvm.org/D40759

See https://github.com/WebAssembly/tool-conventions/issues/25

Subscribers: jfb, dschuff, jgravelle-google, aheejin, sunfish

Differential Revision: https://reviews.llvm.org/D41208

llvm-svn: 320742

1 files changed, 7 insertions, 0 deletions

diff --git a/llvm/lib/ObjectYAML/WasmYAML.cpp b/llvm/lib/ObjectYAML/WasmYAML.cpp
index c206a682b83..8687f22949a 100644
--- a/llvm/lib/ObjectYAML/WasmYAML.cpp
+++ b/llvm/lib/ObjectYAML/WasmYAML.cpp
@@ -60,6 +60,7 @@ static void sectionMapping(IO &IO, WasmYAML::LinkingSection &Section) {
   IO.mapRequired("DataSize", Section.DataSize);
   IO.mapOptional("SymbolInfo", Section.SymbolInfos);
   IO.mapOptional("SegmentInfo", Section.SegmentInfos);
+  IO.mapOptional("InitFunctions", Section.InitFunctions);
 }
 
 static void sectionMapping(IO &IO, WasmYAML::CustomSection &Section) {
@@ -359,6 +360,12 @@ void MappingTraits<WasmYAML::DataSegment>::mapping(
   IO.mapRequired("Content", Segment.Content);
 }
 
+void MappingTraits<WasmYAML::InitFunction>::mapping(
+    IO &IO, WasmYAML::InitFunction &Init) {
+  IO.mapRequired("Priority", Init.Priority);
+  IO.mapRequired("FunctionIndex", Init.FunctionIndex);
+}
+
 void MappingTraits<WasmYAML::SymbolInfo>::mapping(IO &IO,
                                                   WasmYAML::SymbolInfo &Info) {
   IO.mapRequired("Name", Info.Name);