Do not compare reference values across executions (#5276)

Since we optimize assuming a closed world, optimizations can change the types
and structure of GC data even in externally-visible ways. Because differences
are expected, the fuzzer already did not compare reference-typed values from
before and after optimizations when running with nominal typing. Update it to
not compare these values under any type system.

1 files changed, 22 insertions, 0 deletions

diff --git a/test/lit/exec/no-compare-refs.wast b/test/lit/exec/no-compare-refs.wast
new file mode 100644
index 000000000..bb9766a31
--- /dev/null
+++ b/test/lit/exec/no-compare-refs.wast
@@ -0,0 +1,22 @@
+;; NOTE: Assertions have been generated by update_lit_checks.py --output=fuzz-exec and should not be edited.
+
+;; RUN: wasm-opt %s --hybrid -all --signature-pruning --fuzz-exec -q -o /dev/null 2>&1 | filecheck %s
+
+(module
+  (type $f (func (param i32)))
+
+  (func $no-use-param (type $f) (param i32)
+    (unreachable)
+  )
+
+  ;; The type of the reference this function returns will change as a result of
+  ;; signature pruning. The fuzzer should not complain about this.
+  ;; CHECK:      [fuzz-exec] calling return-ref
+  ;; CHECK-NEXT: [fuzz-exec] note result: return-ref => funcref
+  (func "return-ref" (result funcref)
+    (ref.func $no-use-param)
+  )
+)
+;; CHECK:      [fuzz-exec] calling return-ref
+;; CHECK-NEXT: [fuzz-exec] note result: return-ref => funcref
+;; CHECK-NEXT: [fuzz-exec] comparing return-ref