Print only literal values when printing literals (#2469)

Current `<<` operator on `Literal` prints `[type].const` with it. But
`[type].const` is rather an instruction than a literal itself, and
printing it with the literals makes less sense when we later have
literals whose type don't have `const` instructions (such as reference
types).

This patch
- Makes `<<` operator on `Literal` print only its value
- Makes wasm-shell's shell interface comply with the spec interpreter's
  printing format (`value : type`).
- Prints wasm-shell's `[trap]` message to stderr

These make all `fix_` routines for spec tests in check.py unnecessary.

1 files changed, 3 insertions, 1 deletions

diff --git a/src/passes/Print.cpp b/src/passes/Print.cpp
index fef4ac01d..e35d9b57e 100644
--- a/src/passes/Print.cpp
+++ b/src/passes/Print.cpp
@@ -447,7 +447,9 @@ struct PrintExpressionContents
     prepareColor(o);
     o << "memory.fill";
   }
-  void visitConst(Const* curr) { o << curr->value; }
+  void visitConst(Const* curr) {
+    o << curr->value.type << ".const " << curr->value;
+  }
   void visitUnary(Unary* curr) {
     prepareColor(o);
     switch (curr->op) {