CodeFolding: Fix up old EH when we fold away an If (#6420)

The pass does (among other things) this:

(if
  condition
  X
  X
)

=>

(block
  (drop
    condition
  )
  X ;; deduplicated
)

After that the condition is now nested in a block, so we may need EH fixups
if it contains a pop.

1 files changed, 57 insertions, 1 deletions

diff --git a/test/lit/passes/code-folding-eh-old.wast b/test/lit/passes/code-folding-eh-old.wast
index e83559c2b..836df867c 100644
--- a/test/lit/passes/code-folding-eh-old.wast
+++ b/test/lit/passes/code-folding-eh-old.wast
@@ -72,7 +72,7 @@
   ;; CHECK-NEXT: )
   (func $foo)
 
-  ;; CHECK:      (func $try-call-optimize-terminating-tails (type $2) (result i32)
+  ;; CHECK:      (func $try-call-optimize-terminating-tails (type $1) (result i32)
   ;; CHECK-NEXT:  (try
   ;; CHECK-NEXT:   (do
   ;; CHECK-NEXT:    (call $foo)
@@ -155,4 +155,60 @@
       (unreachable)
     )
   )
+
+  ;; CHECK:      (func $if-arms-in-catch (type $1) (result i32)
+  ;; CHECK-NEXT:  (local $0 i32)
+  ;; CHECK-NEXT:  (try
+  ;; CHECK-NEXT:   (do
+  ;; CHECK-NEXT:    (unreachable)
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:   (catch $e-i32
+  ;; CHECK-NEXT:    (local.set $0
+  ;; CHECK-NEXT:     (pop i32)
+  ;; CHECK-NEXT:    )
+  ;; CHECK-NEXT:    (block
+  ;; CHECK-NEXT:     (block
+  ;; CHECK-NEXT:      (drop
+  ;; CHECK-NEXT:       (local.get $0)
+  ;; CHECK-NEXT:      )
+  ;; CHECK-NEXT:      (drop
+  ;; CHECK-NEXT:       (i32.eqz
+  ;; CHECK-NEXT:        (i32.const 1)
+  ;; CHECK-NEXT:       )
+  ;; CHECK-NEXT:      )
+  ;; CHECK-NEXT:     )
+  ;; CHECK-NEXT:     (unreachable)
+  ;; CHECK-NEXT:    )
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:  )
+  ;; CHECK-NEXT: )
+  (func $if-arms-in-catch (result i32)
+    (try
+      (do
+        (unreachable)
+      )
+      (catch $e-i32
+        ;; These if arms can be folded, after which the if is replaced by a
+        ;; block, so we need a fixup for the pop.
+        (if
+          (pop i32)
+          (then
+            (drop
+              (i32.eqz
+                (i32.const 1)
+              )
+            )
+          )
+          (else
+            (drop
+              (i32.eqz
+                (i32.const 1)
+              )
+            )
+          )
+        )
+        (unreachable)
+      )
+    )
+  )
 )