add missing checks on nested blocks in SimplifyExpressions

3 files changed, 33 insertions, 2 deletions

diff --git a/src/passes/SimplifyLocals.cpp b/src/passes/SimplifyLocals.cpp
index 5368701d7..0d59b8759 100644
--- a/src/passes/SimplifyLocals.cpp
+++ b/src/passes/SimplifyLocals.cpp
@@ -45,14 +45,19 @@ struct SimplifyLocals : public WalkerPass<FastExecutionWalker<SimplifyLocals>> {
 
   void visitBlock(Block *curr) {
     // note locals, we can sink them from here TODO sink from elsewhere?
-    derecurseBlocks(curr, [&](Block* block) {}, [&](Block* block, Expression*& child) {
+    derecurseBlocks(curr, [&](Block* block) {
+      // curr was already checked by walk()
+      if (block != curr) checkPre(block);
+    }, [&](Block* block, Expression*& child) {
       walk(child);
       if (child->is<SetLocal>()) {
         Name name = child->cast<SetLocal>()->name;
         assert(sinkables.count(name) == 0);
         sinkables.emplace(std::make_pair(name, SinkableInfo(&child)));
       }
-    }, [&](Block* block) {});
+    }, [&](Block* block) {
+      if (block != curr) checkPost(block);
+    });
   }
 
   void visitGetLocal(GetLocal *curr) {
diff --git a/test/passes/simplify-locals.txt b/test/passes/simplify-locals.txt
index 880639f79..95b714eb9 100644
--- a/test/passes/simplify-locals.txt
+++ b/test/passes/simplify-locals.txt
@@ -253,4 +253,17 @@
       (get_local $a)
     )
   )
+  (func $Ia (param $a i32) (result i32)
+    (local $b i32)
+    (block $switch$0
+      (block $switch-default$6
+        (set_local $b
+          (i32.const 60)
+        )
+      )
+    )
+    (return
+      (get_local $b)
+    )
+  )
 )
diff --git a/test/passes/simplify-locals.wast b/test/passes/simplify-locals.wast
index db17c5533..24f8476d2 100644
--- a/test/passes/simplify-locals.wast
+++ b/test/passes/simplify-locals.wast
@@ -145,5 +145,18 @@
       (get_local $a)
     )
   )
+  (func $Ia (param $a i32) (result i32)
+    (local $b i32)
+    (block $switch$0
+      (block $switch-default$6
+        (set_local $b
+          (i32.const 60)
+        )
+      )
+    )
+    (return
+      (get_local $b)
+    )
+  )
 )