Update testsuite (w/ reference-types changes) (#1351)

The new table-sub test, checks whether the subtyping is handled
properly w/ table.init and table.copy instructions.

The BeginElemSegment callback can't pass the element type anymore, since
it's not known yet. The callback also can't be deferred, since the
BeginElemSegmentInitExpr callback has to happen after the
BeginElemSegment callback, but the reference type is not always known
until after the initializer expression is read. To work around this, I
added a new OnElemSegmentElemType callback.

Other element segment changes:

* The element type must be tracked in the SharedValidator
* A subtle fix: when writing out the segment flags, we need to take into
  account whether the element type of the segment is not funcref, even
  if there are no element expressions. In that case, we have to use flag
  bit 0x4 (SegUseElemExprs).

In addition, the TableCopy and TableInit instructions weren't handling
table indexes fully.

* TableCopy variables are read in the parser (both optional)
* TableCopy names are now resolved + applied
* TableCopy indexes are now validated
* TableInit table variables are read in the parser; this is subtle,
  since the text format has order $table $segment, but the $table is
  optional.

1 files changed, 15 insertions, 5 deletions

diff --git a/src/wast-parser.cc b/src/wast-parser.cc
index 3468e008..3075ee91 100644
--- a/src/wast-parser.cc
+++ b/src/wast-parser.cc
@@ -1820,11 +1820,8 @@ Result WastParser::ParsePlainInstr(std::unique_ptr<Expr>* out_expr) {
       Var dst(0, loc);
       Var src(0, loc);
       if (options_->features.reference_types_enabled()) {
-      // TODO: disabled for now, since the spec tests don't currently use.
-#if 0
-        CHECK_RESULT(ParseVar(&dst));
-        CHECK_RESULT(ParseVar(&src));
-#endif
+        ParseVarOpt(&dst, dst);
+        ParseVarOpt(&src, src);
       }
       out_expr->reset(new TableCopyExpr(dst, src, loc));
       break;
@@ -1840,6 +1837,15 @@ Result WastParser::ParsePlainInstr(std::unique_ptr<Expr>* out_expr) {
       Var segment_index(0, loc);
       CHECK_RESULT(ParseVar(&segment_index));
       Var table_index(0, loc);
+      if (ParseVarOpt(&table_index, table_index)) {
+        // Here are the two forms:
+        //
+        //   table.init $elemidx ...
+        //   table.init $tableidx $elemidx ...
+        //
+        // So if both indexes are provided, we need to swap them.
+        std::swap(segment_index, table_index);
+      }
       out_expr->reset(new TableInitExpr(segment_index, table_index, loc));
       break;
     }
@@ -1851,21 +1857,25 @@ Result WastParser::ParsePlainInstr(std::unique_ptr<Expr>* out_expr) {
 
     case TokenType::TableSet:
       ErrorUnlessOpcodeEnabled(Consume());
+      // TODO: Table index.
       CHECK_RESULT(ParsePlainInstrVar<TableSetExpr>(loc, out_expr));
       break;
 
     case TokenType::TableGrow:
       ErrorUnlessOpcodeEnabled(Consume());
+      // TODO: Table index.
       CHECK_RESULT(ParsePlainInstrVar<TableGrowExpr>(loc, out_expr));
       break;
 
     case TokenType::TableSize:
       ErrorUnlessOpcodeEnabled(Consume());
+      // TODO: Table index.
       CHECK_RESULT(ParsePlainInstrVar<TableSizeExpr>(loc, out_expr));
       break;
 
     case TokenType::TableFill:
       ErrorUnlessOpcodeEnabled(Consume());
+      // TODO: Table index.
       CHECK_RESULT(ParsePlainInstrVar<TableFillExpr>(loc, out_expr));
       break;