Implement changes of function reference proposal

Author: Zoltan Herczeg

include/wabt/ir.h

@@ -734,9 +734,7 @@ class CallRefExpr : public ExprMixin<ExprType::CallRef> {
   explicit CallRefExpr(const Location& loc = Location())
       : ExprMixin<ExprType::CallRef>(loc) {}
 
-  // This field is setup only during Validate phase,
-  // so keep that in mind when you use it.
-  Var function_type_index;
+  Var function_type;
 };
 
 template <ExprType TypeEnum>

include/wabt/shared-validator.h

@@ -140,7 +140,7 @@ class SharedValidator {
   Result EndBrTable(const Location&);
   Result OnCall(const Location&, Var func_var);
   Result OnCallIndirect(const Location&, Var sig_var, Var table_var);
-  Result OnCallRef(const Location&, Index* function_type_index);
+  Result OnCallRef(const Location&, Var function_type_var);
   Result OnCatch(const Location&, Var tag_var, bool is_catch_all);
   Result OnCompare(const Location&, Opcode);
   Result OnConst(const Location&, Type);

include/wabt/token.def

@@ -55,6 +55,7 @@ WABT_TOKEN(Module, "module")
 WABT_TOKEN(Mut, "mut")
 WABT_TOKEN(NanArithmetic, "nan:arithmetic")
 WABT_TOKEN(NanCanonical, "nan:canonical")
+WABT_TOKEN(Null, "null")
 WABT_TOKEN(Offset, "offset")
 WABT_TOKEN(Output, "output")
 WABT_TOKEN(PageSize, "pagesize")

include/wabt/type.h

@@ -46,6 +46,8 @@ class Type {
     FuncRef = -0x10,    // 0x70
     ExternRef = -0x11,  // 0x6f
     Reference = -0x15,  // 0x6b
+    HeapRef = -0x1c,    // 0x64
+    HeapNullRef = -0x1d, // 0x63
     Func = -0x20,       // 0x60
     Struct = -0x21,     // 0x5f
     Array = -0x22,      // 0x5e
@@ -63,7 +65,8 @@ class Type {
       : enum_(static_cast<Enum>(code)), type_index_(kInvalidIndex) {}
   Type(Enum e) : enum_(e), type_index_(kInvalidIndex) {}
   Type(Enum e, Index type_index) : enum_(e), type_index_(type_index) {
-    assert(e == Enum::Reference);
+    assert(e == Enum::Reference || e == Enum::HeapRef ||
+           e == Enum::HeapNullRef || type_index == kInvalidIndex);
   }
   constexpr operator Enum() const { return enum_; }
 

include/wabt/wast-parser.h

@@ -134,7 +134,7 @@ class WastParser {
   bool ParseElemExprOpt(ExprList* out_elem_expr);
   bool ParseElemExprListOpt(ExprListVector* out_list);
   bool ParseElemExprVarListOpt(ExprListVector* out_list);
-  Result ParseValueType(Var* out_type);
+  Result ParseValueType(Type::Enum *out_code, Var* out_type);
   Result ParseValueTypeList(
       TypeVector* out_type_list,
       std::unordered_map<uint32_t, std::string>* type_names);

src/ir-util.cc

@@ -140,7 +140,7 @@ ModuleContext::Arities ModuleContext::GetExprArity(const Expr& expr) const {
     }
 
     case ExprType::CallRef: {
-      const Var& var = cast<CallRefExpr>(&expr)->function_type_index;
+      const Var& var = cast<CallRefExpr>(&expr)->function_type;
       return {GetFuncParamCount(var) + 1, GetFuncResultCount(var)};
     }
 

src/lexer-keywords.txt

@@ -556,6 +556,7 @@ mut, TokenType::Mut
 nan:arithmetic, TokenType::NanArithmetic
 nan:canonical, TokenType::NanCanonical
 nop, TokenType::Nop, Opcode::Nop
+null, TokenType::Null
 offset, TokenType::Offset
 output, TokenType::Output
 pagesize, TokenType::PageSize