[NFC] Send the closed-world flag to TranslateToFuzzReader (#7136)

This sends --closed-world to wasm-opt from the fuzzer, when we use that
flag (before we just used it on optimizations, but not fuzz generation). And
TranslateToFuzzReader now stores a boolean about whether we are in closed-
world mode or not.

This has no effect so far, and is a refactoring for a later PR, where we must
generate code differently based on whether we are in closed-world mode
or not.

1 files changed, 6 insertions, 4 deletions

diff --git a/scripts/fuzz_opt.py b/scripts/fuzz_opt.py
index 299403837..b60a3e29a 100755
--- a/scripts/fuzz_opt.py
+++ b/scripts/fuzz_opt.py
@@ -225,10 +225,12 @@ def randomize_fuzz_settings():
         # optimizations we use to create any other wasm file.
         FUZZ_OPTS += ['--dce']
 
-    # Enclose the world much of the time when fuzzing closed-world, so that many
-    # types are private and hence optimizable.
-    if CLOSED_WORLD and random.random() < 0.5:
-        GEN_ARGS += ['--enclose-world']
+    if CLOSED_WORLD:
+        GEN_ARGS += [CLOSED_WORLD_FLAG]
+        # Enclose the world much of the time when fuzzing closed-world, so that
+        # many types are private and hence optimizable.
+        if random.random() < 0.5:
+            GEN_ARGS += ['--enclose-world']
 
     print('randomized settings (NaNs, OOB, legalize):', NANS, OOB, LEGALIZE)