Add a pass for minimizing recursion groups

scripts/fuzz_opt.py

@@ -1571,6 +1571,7 @@ def write_commands(commands, filename):
     ('--monomorphize', '--pass-arg=monomorphize-min-benefit@50'),
     ('--monomorphize', '--pass-arg=monomorphize-min-benefit@95'),
     ('--monomorphize-always',),
+    ('--minimize-rec-groups',),
     ('--no-stack-ir',),
     ('--once-reduction',),
     ("--optimize-casts",),

src/passes/CMakeLists.txt

@@ -67,6 +67,7 @@ set(passes_SOURCES
   MergeLocals.cpp
   Metrics.cpp
   MinifyImportsAndExports.cpp
+  MinimizeRecGroups.cpp
   Monomorphize.cpp
   MultiMemoryLowering.cpp
   NameList.cpp