ReFinalize fuzz fix (#1771)

If we refinalize after adding a value that flows out of a block, we need to fix up any branches that might exist without a value, which is possible if the branches were not taken in practice

Also refactor ReFinalize into a separate file.

2 files changed, 45 insertions, 0 deletions

diff --git a/test/passes/remove-unused-brs.txt b/test/passes/remove-unused-brs.txt
index a44a62c20..774110e23 100644
--- a/test/passes/remove-unused-brs.txt
+++ b/test/passes/remove-unused-brs.txt
@@ -2208,4 +2208,27 @@
    (br $label$1)
   )
  )
+ (func $refinalize-need-br-value (; 101 ;) (type $2) (result i32)
+  (loop $label$3 (result i32)
+   (block $label$6 (result i32)
+    (block $label$10 (result i32)
+     (unreachable)
+     (block $label$503 (result i32)
+      (br_if $label$3
+       (block $label$530 (result i32)
+        (block
+         (unreachable)
+         (drop
+          (i32.const 0)
+         )
+        )
+        (i32.const 0)
+       )
+      )
+      (i32.const 127)
+     )
+    )
+   )
+  )
+ )
 )
diff --git a/test/passes/remove-unused-brs.wast b/test/passes/remove-unused-brs.wast
index 7a1943c14..d1afba4a5 100644
--- a/test/passes/remove-unused-brs.wast
+++ b/test/passes/remove-unused-brs.wast
@@ -1815,5 +1815,27 @@
     (br $label$1)
    )
   )
+  (func $refinalize-need-br-value (result i32)
+   (loop $label$3 (result i32)
+    (block $label$6 (result i32)
+     (block $label$10
+      (unreachable)
+      (block $label$503 ;; this block will get a value flowing out
+       (br_if $label$3
+        (block $label$530 (result i32)
+         (br_if $label$503 ;; while this br does not send a value
+          (i32.const 0)
+         )
+         (i32.const 0)
+        )
+       )
+       (return
+        (i32.const 127)
+       )
+      )
+     )
+    )
+   )
+  )
 )