ExtractFunction: Do not always remove the memory and table (#3877)

Instead, run RemoveUnusedModuleElements, which does that sort of thing. That
is, this pass just "extracts" the function by turning all others into imports, and then
they should almost all be removable via RemoveUnusedModuleElements, depending
on whether they are used in the table or not, whether the extracted function calls
them, etc.

Without this, we would error if a function was in the table, and so this fixes #3876

1 files changed, 25 insertions, 1 deletions

diff --git a/test/passes/extract-function_pass-arg=extract@foo.wast b/test/passes/extract-function_pass-arg=extract@foo.wast
index 876910300..ab1d8b269 100644
--- a/test/passes/extract-function_pass-arg=extract@foo.wast
+++ b/test/passes/extract-function_pass-arg=extract@foo.wast
@@ -9,4 +9,28 @@
     (drop (i32.const 1))
   )
 )
-
+(module
+  ;; Use another function in the table, but the table is not used in the
+  ;; extracted function
+  (table $t 10 funcref)
+  (elem $0 (table $t) (i32.const 0) func $other)
+  (func $foo
+  )
+  (func $other
+    (drop (i32.const 1))
+  )
+)
+(module
+  ;; Use another function in the table, and the table *is* used. As a result,
+  ;; the table and its elements will remain. The called function, $other, will
+  ;; remain as an import that is placed in the table.
+  (type $none (func))
+  (table $t 10 funcref)
+  (elem $0 (table $t) (i32.const 0) func $other)
+  (func $foo
+   (call_indirect (type $none) (i32.const 10))
+  )
+  (func $other
+    (drop (i32.const 1))
+  )
+)