Fuzzer: Add a pass to prune illegal imports and exports for JS (#6312)

We already have passes to legalize i64 imports and exports, which the fuzzer will
run so that we can run wasm files in JS VMs. SIMD and multivalue also pose a
problem as they trap on the boundary. In principle we could legalize them as well,
but that is substantial effort, so instead just prune them: given a wasm module,
remove any imports or exports that use SIMD or multivalue (or anything else that
is not legal for JS).

Running this in the fuzzer will allow us to not skip running v8 on any testcase we
enable SIMD and multivalue for.

(Multivalue is allowed in newer VMs, so that part of this PR could be removed
eventually.)

Also remove the limitation on running v8 with multimemory (v8 now supports
that).

1 files changed, 3 insertions, 0 deletions

diff --git a/test/lit/help/wasm2js.test b/test/lit/help/wasm2js.test
index aadefe8fc..9804718a8 100644
--- a/test/lit/help/wasm2js.test
+++ b/test/lit/help/wasm2js.test
@@ -179,6 +179,9 @@
 ;; CHECK-NEXT:   --jspi                                        wrap imports and exports for
 ;; CHECK-NEXT:                                                 JavaScript promise integration
 ;; CHECK-NEXT:
+;; CHECK-NEXT:   --legalize-and-prune-js-interface             legalizes the import/export
+;; CHECK-NEXT:                                                 boundary and prunes when needed
+;; CHECK-NEXT:
 ;; CHECK-NEXT:   --legalize-js-interface                       legalizes i64 types on the
 ;; CHECK-NEXT:                                                 import/export boundary
 ;; CHECK-NEXT: