Proper encoding of passive element segments (#1066)

* Store element segments as a vector of `ElemExpr`, instead of func index
* Read/write binary format for each element expression
* Read/write text format for each element expression

1 files changed, 16 insertions, 10 deletions

diff --git a/src/binary-reader-ir.cc b/src/binary-reader-ir.cc
index 9d71f70b..dd7efeee 100644
--- a/src/binary-reader-ir.cc
+++ b/src/binary-reader-ir.cc
@@ -201,8 +201,10 @@ class BinaryReaderIR : public BinaryReaderNop {
   Result BeginElemSegment(Index index, Index table_index, bool passive) override;
   Result BeginElemSegmentInitExpr(Index index) override;
   Result EndElemSegmentInitExpr(Index index) override;
-  Result OnElemSegmentFunctionIndexCount(Index index, Index count) override;
-  Result OnElemSegmentFunctionIndex(Index index, Index func_index) override;
+  Result OnElemSegmentElemExprCount(Index index, Index count) override;
+  Result OnElemSegmentElemExpr_RefNull(Index segment_index) override;
+  Result OnElemSegmentElemExpr_RefFunc(Index segment_index,
+                                       Index func_index) override;
 
   Result OnDataSegmentCount(Index count) override;
   Result BeginDataSegment(Index index, Index memory_index, bool passive) override;
@@ -1003,23 +1005,27 @@ Result BinaryReaderIR::EndElemSegmentInitExpr(Index index) {
   return Result::Ok;
 }
 
-Result BinaryReaderIR::OnElemSegmentFunctionIndexCount(Index index,
-                                                       Index count) {
+Result BinaryReaderIR::OnElemSegmentElemExprCount(Index index, Index count) {
   assert(index == module_->elem_segments.size() - 1);
   ElemSegment* segment = module_->elem_segments[index];
   WABT_TRY
-  segment->vars.reserve(count);
+  segment->elem_exprs.reserve(count);
   WABT_CATCH_BAD_ALLOC
   return Result::Ok;
 }
 
-Result BinaryReaderIR::OnElemSegmentFunctionIndex(Index segment_index,
-                                                  Index func_index) {
+Result BinaryReaderIR::OnElemSegmentElemExpr_RefNull(Index segment_index) {
   assert(segment_index == module_->elem_segments.size() - 1);
   ElemSegment* segment = module_->elem_segments[segment_index];
-  segment->vars.emplace_back();
-  Var* var = &segment->vars.back();
-  *var = Var(func_index, GetLocation());
+  segment->elem_exprs.emplace_back();
+  return Result::Ok;
+}
+
+Result BinaryReaderIR::OnElemSegmentElemExpr_RefFunc(Index segment_index,
+                                                     Index func_index) {
+  assert(segment_index == module_->elem_segments.size() - 1);
+  ElemSegment* segment = module_->elem_segments[segment_index];
+  segment->elem_exprs.emplace_back(Var(func_index, GetLocation()));
   return Result::Ok;
 }