Prevent calls from sinking into 'try' (#2899)

Expressions that may throw cannot be sinked into 'try'. At the start of
'try', we drop all sinkables that may throw.

Author: aheejin

src/passes/SimplifyLocals.cpp

@@ -302,6 +302,20 @@ struct SimplifyLocals
            Expression** currp) {
     Expression* curr = *currp;
 
+    // Expressions that may throw cannot be sinked into 'try'. At the start of
+    // 'try', we drop all sinkables that may throw.
+    if (curr->is<Try>()) {
+      std::vector<Index> invalidated;
+      for (auto& sinkable : self->sinkables) {
+        if (sinkable.second.effects.throws) {
+          invalidated.push_back(sinkable.first);
+        }
+      }
+      for (auto index : invalidated) {
+        self->sinkables.erase(index);
+      }
+    }
+
     EffectAnalyzer effects(self->getPassOptions(), self->getModule()->features);
     if (effects.checkPre(curr)) {
       self->checkInvalidations(effects);

test/passes/simplify-locals_all-features.txt

@@ -1896,6 +1896,7 @@
  (type $none_=>_none (func))
  (type $i32_exnref_=>_none (func (param i32 exnref)))
  (type $exnref_=>_none (func (param exnref)))
+ (type $none_=>_i32 (func (result i32)))
  (type $none_=>_exnref (func (result exnref)))
  (event $event$0 (attr 0) (param))
  (event $event$1 (attr 0) (param exnref))
@@ -1980,4 +1981,41 @@
    )
   )
  )
+ (func $bar (result i32)
+  (i32.const 3)
+ )
+ (func $call-cannot-be-sinked-into-try
+  (local $0 i32)
+  (local.set $0
+   (call $bar)
+  )
+  (try
+   (do
+    (drop
+     (local.get $0)
+    )
+   )
+   (catch
+    (drop
+     (exnref.pop)
+    )
+   )
+  )
+ )
+ (func $non-call-can-be-sinked-into-try
+  (local $0 i32)
+  (nop)
+  (try
+   (do
+    (drop
+     (i32.const 3)
+    )
+   )
+   (catch
+    (drop
+     (exnref.pop)
+    )
+   )
+  )
+ )
 )

test/passes/simplify-locals_all-features.wast

@@ -1749,4 +1749,36 @@
       )
     )
   )
+
+  (func $bar (result i32) (i32.const 3))
+  (func $call-cannot-be-sinked-into-try (local $0 i32)
+    (drop
+      ;; This local.tee should NOT be sinked into 'try' below, because it may
+      ;; throw
+      (local.tee $0 (call $bar))
+    )
+    (try
+      (do
+        (drop (local.get $0))
+      )
+      (catch
+        (drop (exnref.pop))
+      )
+    )
+  )
+
+  (func $non-call-can-be-sinked-into-try (local $0 i32)
+    (drop
+      ;; This local.tee can be sinked into 'try' below, because it cannot throw
+      (local.tee $0 (i32.const 3))
+    )
+    (try
+      (do
+        (drop (local.get $0))
+      )
+      (catch
+        (drop (exnref.pop))
+      )
+    )
+  )
 )