Support more reference constants in wast scripts (#6865)

Spec tests use constants like `ref.array` and `ref.eq` to assert that
exported function return references of the correct types. Support more
such constants in the wast parser.

Also fix a bug where the interpretation of `array.new_data` for arrays
of packed fields was not properly truncating the packed data. Move the
function for reading fields from memory from literal.cpp to
wasm-interpreter.h, where the function for truncating packed data lives.

Other bugs prevent us from enabling any more spec tests as a result of
this change, but we can get farther through several of them before
failing. Update the comments about the failures accordingly.

1 files changed, 28 insertions, 0 deletions

diff --git a/src/parser/wast-parser.cpp b/src/parser/wast-parser.cpp
index 00269a577..5eaf352b7 100644
--- a/src/parser/wast-parser.cpp
+++ b/src/parser/wast-parser.cpp
@@ -217,6 +217,34 @@ Result<ExpectedResult> result(Lexer& in) {
     return RefResult{HeapType::func};
   }
 
+  if (in.takeSExprStart("ref.struct")) {
+    if (!in.takeRParen()) {
+      return in.err("expected end of ref.struct");
+    }
+    return RefResult{HeapType::struct_};
+  }
+
+  if (in.takeSExprStart("ref.array")) {
+    if (!in.takeRParen()) {
+      return in.err("expected end of ref.array");
+    }
+    return RefResult{HeapType::array};
+  }
+
+  if (in.takeSExprStart("ref.eq")) {
+    if (!in.takeRParen()) {
+      return in.err("expected end of ref.eq");
+    }
+    return RefResult{HeapType::eq};
+  }
+
+  if (in.takeSExprStart("ref.i31")) {
+    if (!in.takeRParen()) {
+      return in.err("expected end of ref.i31");
+    }
+    return RefResult{HeapType::i31};
+  }
+
   if (in.takeSExprStart("ref.i31_shared")) {
     if (!in.takeRParen()) {
       return in.err("expected end of ref.i31_shared");