[Wasm GC] Full precompute support for GC (#3803)

The precompute pass ignored all reference types, but that was overly
pessimistic: we can precompute some of them, namely a null and a
reference to a function are fully precomputable, etc.

To allow that to work, add missing integration in getFallthrough as well.

With this, we can precompute quite a lot of field accesses in the existing
-Oz testcase, as can be seen from the output. That testcase runs
--fuzz-exec so it prints out all those logged values, proving they have
not changed.

0 files changed, 0 insertions, 0 deletions