diff --git a/src/passes/Vacuum.cpp b/src/passes/Vacuum.cpp
index ac645e77549..961f7eeefe0 100644
--- a/src/passes/Vacuum.cpp
+++ b/src/passes/Vacuum.cpp
@@ -331,17 +331,6 @@ struct Vacuum : public WalkerPass<ExpressionStackWalker<Vacuum>> {
         curr->condition =
           Builder(*getModule()).makeUnary(EqZInt32, curr->condition);
         BranchHints::flip(curr, getFunction());
-      } else if (curr->ifTrue->is<Drop>() && curr->ifFalse->is<Drop>()) {
-        // instead of dropping both sides, drop the if, if they are the same
-        // type
-        auto* left = curr->ifTrue->cast<Drop>()->value;
-        auto* right = curr->ifFalse->cast<Drop>()->value;
-        if (left->type == right->type) {
-          curr->ifTrue = left;
-          curr->ifFalse = right;
-          curr->finalize();
-          replaceCurrent(Builder(*getModule()).makeDrop(curr));
-        }
       }
     } else {
       // This is an if without an else. If the body is empty, we do not need it.
@@ -427,9 +416,11 @@ struct Vacuum : public WalkerPass<ExpressionStackWalker<Vacuum>> {
         }
       }
     }
-    // sink a drop into an arm of an if-else if the other arm ends in an
-    // unreachable, as it if is a branch, this can make that branch optimizable
-    // and more vacuuming possible
+    // Sink a drop into an arm of an if-else if the other arm ends in an
+    // unreachable, or sink drops into both arms if both arms are concrete.
+    // This allows the if expression to become void, eliminates block type
+    // overhead, and enables further vacuuming/dead-code elimination in each
+    // arm.
     auto* iff = curr->value->dynCast<If>();
     if (iff && iff->ifFalse && iff->type.isConcrete()) {
       // reuse the drop in both cases
@@ -445,6 +436,13 @@ struct Vacuum : public WalkerPass<ExpressionStackWalker<Vacuum>> {
         iff->ifTrue = curr;
         iff->type = Type::none;
         replaceCurrent(iff);
+      } else if (iff->ifTrue->type.isConcrete() &&
+                 iff->ifFalse->type.isConcrete()) {
+        Builder builder(*getModule());
+        iff->ifTrue = builder.dropIfConcretelyTyped(iff->ifTrue);
+        iff->ifFalse = builder.dropIfConcretelyTyped(iff->ifFalse);
+        iff->type = Type::none;
+        replaceCurrent(iff);
       }
     }
   }
diff --git a/test/lit/passes/dae-optimizing.wast b/test/lit/passes/dae-optimizing.wast
index 316c377586f..e7177a07138 100644
--- a/test/lit/passes/dae-optimizing.wast
+++ b/test/lit/passes/dae-optimizing.wast
@@ -8,7 +8,7 @@
  (type $1 (func (param f64 f32 f32 f64 f32 i64 f64) (result i32)))
  ;; CHECK:      (type $3 (func (result i32)))
 
- ;; CHECK:      (type $4 (func (result f32)))
+ ;; CHECK:      (type $4 (func))
 
  ;; CHECK:      (type $2 (func (param f64 f32 f32 f64 f32 i32 i32 f64) (result i32)))
  (type $2 (func (param f64 f32 f32 f64 f32 i32 i32 f64) (result i32)))
@@ -17,12 +17,12 @@
  ;; CHECK:      (func $0 (type $3) (result i32)
  ;; CHECK-NEXT:  (local $0 i32)
  ;; CHECK-NEXT:  (local $1 i32)
- ;; CHECK-NEXT:  (drop
- ;; CHECK-NEXT:   (if (result f32)
- ;; CHECK-NEXT:    (local.tee $0
- ;; CHECK-NEXT:     (i32.const 33554432)
- ;; CHECK-NEXT:    )
- ;; CHECK-NEXT:    (then
+ ;; CHECK-NEXT:  (if
+ ;; CHECK-NEXT:   (local.tee $0
+ ;; CHECK-NEXT:    (i32.const 33554432)
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:   (then
+ ;; CHECK-NEXT:    (drop
  ;; CHECK-NEXT:     (loop $label$2 (result f32)
  ;; CHECK-NEXT:      (if
  ;; CHECK-NEXT:       (global.get $global$0)
@@ -44,9 +44,9 @@
  ;; CHECK-NEXT:      (f32.const 1)
  ;; CHECK-NEXT:     )
  ;; CHECK-NEXT:    )
- ;; CHECK-NEXT:    (else
- ;; CHECK-NEXT:     (call $1)
- ;; CHECK-NEXT:    )
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:   (else
+ ;; CHECK-NEXT:    (call $1)
  ;; CHECK-NEXT:   )
  ;; CHECK-NEXT:  )
  ;; CHECK-NEXT:  (i32.const -11)
@@ -96,8 +96,8 @@
   )
   (i32.const -11)
  )
- ;; CHECK:      (func $1 (type $4) (result f32)
- ;; CHECK-NEXT:  (f32.const 0)
+ ;; CHECK:      (func $1 (type $4)
+ ;; CHECK-NEXT:  (nop)
  ;; CHECK-NEXT: )
  (func $1 (; 1 ;) (type $0) (param $0 f32) (result f32)
   (f32.const 0)
diff --git a/test/lit/passes/inlining-optimizing_optimize-level=3.wast b/test/lit/passes/inlining-optimizing_optimize-level=3.wast
index bf931609666..5707cf6dfba 100644
--- a/test/lit/passes/inlining-optimizing_optimize-level=3.wast
+++ b/test/lit/passes/inlining-optimizing_optimize-level=3.wast
@@ -418,188 +418,182 @@
  ;; CHECK-NEXT:    (local.get $6)
  ;; CHECK-NEXT:   )
  ;; CHECK-NEXT:  )
- ;; CHECK-NEXT:  (drop
- ;; CHECK-NEXT:   (if (result i32)
- ;; CHECK-NEXT:    (i32.lt_s
- ;; CHECK-NEXT:     (call $_printf_core
- ;; CHECK-NEXT:      (i32.const 0)
- ;; CHECK-NEXT:      (i32.const 672)
- ;; CHECK-NEXT:      (local.get $2)
- ;; CHECK-NEXT:      (local.get $1)
- ;; CHECK-NEXT:      (local.get $7)
- ;; CHECK-NEXT:     )
+ ;; CHECK-NEXT:  (if
+ ;; CHECK-NEXT:   (i32.ge_s
+ ;; CHECK-NEXT:    (call $_printf_core
  ;; CHECK-NEXT:     (i32.const 0)
+ ;; CHECK-NEXT:     (i32.const 672)
+ ;; CHECK-NEXT:     (local.get $2)
+ ;; CHECK-NEXT:     (local.get $1)
+ ;; CHECK-NEXT:     (local.get $7)
  ;; CHECK-NEXT:    )
- ;; CHECK-NEXT:    (then
- ;; CHECK-NEXT:     (i32.const -1)
+ ;; CHECK-NEXT:    (i32.const 0)
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:   (then
+ ;; CHECK-NEXT:    (drop
+ ;; CHECK-NEXT:     (i32.load offset=76
+ ;; CHECK-NEXT:      (local.get $0)
+ ;; CHECK-NEXT:     )
  ;; CHECK-NEXT:    )
- ;; CHECK-NEXT:    (else
- ;; CHECK-NEXT:     (drop
- ;; CHECK-NEXT:      (i32.load offset=76
+ ;; CHECK-NEXT:    (local.set $3
+ ;; CHECK-NEXT:     (i32.load
+ ;; CHECK-NEXT:      (local.get $0)
+ ;; CHECK-NEXT:     )
+ ;; CHECK-NEXT:    )
+ ;; CHECK-NEXT:    (if
+ ;; CHECK-NEXT:     (i32.le_s
+ ;; CHECK-NEXT:      (i32.load8_s offset=74
  ;; CHECK-NEXT:       (local.get $0)
  ;; CHECK-NEXT:      )
+ ;; CHECK-NEXT:      (i32.const 0)
  ;; CHECK-NEXT:     )
- ;; CHECK-NEXT:     (local.set $3
- ;; CHECK-NEXT:      (i32.load
+ ;; CHECK-NEXT:     (then
+ ;; CHECK-NEXT:      (i32.store
  ;; CHECK-NEXT:       (local.get $0)
+ ;; CHECK-NEXT:       (i32.and
+ ;; CHECK-NEXT:        (local.get $3)
+ ;; CHECK-NEXT:        (i32.const -33)
+ ;; CHECK-NEXT:       )
  ;; CHECK-NEXT:      )
  ;; CHECK-NEXT:     )
- ;; CHECK-NEXT:     (if
- ;; CHECK-NEXT:      (i32.le_s
- ;; CHECK-NEXT:       (i32.load8_s offset=74
+ ;; CHECK-NEXT:    )
+ ;; CHECK-NEXT:    (if
+ ;; CHECK-NEXT:     (i32.load
+ ;; CHECK-NEXT:      (local.tee $5
+ ;; CHECK-NEXT:       (i32.add
  ;; CHECK-NEXT:        (local.get $0)
+ ;; CHECK-NEXT:        (i32.const 48)
  ;; CHECK-NEXT:       )
- ;; CHECK-NEXT:       (i32.const 0)
  ;; CHECK-NEXT:      )
- ;; CHECK-NEXT:      (then
- ;; CHECK-NEXT:       (i32.store
+ ;; CHECK-NEXT:     )
+ ;; CHECK-NEXT:     (then
+ ;; CHECK-NEXT:      (drop
+ ;; CHECK-NEXT:       (call $_printf_core
  ;; CHECK-NEXT:        (local.get $0)
- ;; CHECK-NEXT:        (i32.and
- ;; CHECK-NEXT:         (local.get $3)
- ;; CHECK-NEXT:         (i32.const -33)
- ;; CHECK-NEXT:        )
+ ;; CHECK-NEXT:        (i32.const 672)
+ ;; CHECK-NEXT:        (local.get $2)
+ ;; CHECK-NEXT:        (local.get $1)
+ ;; CHECK-NEXT:        (local.get $7)
  ;; CHECK-NEXT:       )
  ;; CHECK-NEXT:      )
  ;; CHECK-NEXT:     )
- ;; CHECK-NEXT:     (if
- ;; CHECK-NEXT:      (i32.load
- ;; CHECK-NEXT:       (local.tee $5
- ;; CHECK-NEXT:        (i32.add
- ;; CHECK-NEXT:         (local.get $0)
- ;; CHECK-NEXT:         (i32.const 48)
+ ;; CHECK-NEXT:     (else
+ ;; CHECK-NEXT:      (local.set $10
+ ;; CHECK-NEXT:       (i32.load
+ ;; CHECK-NEXT:        (local.tee $9
+ ;; CHECK-NEXT:         (i32.add
+ ;; CHECK-NEXT:          (local.get $0)
+ ;; CHECK-NEXT:          (i32.const 44)
+ ;; CHECK-NEXT:         )
  ;; CHECK-NEXT:        )
  ;; CHECK-NEXT:       )
  ;; CHECK-NEXT:      )
- ;; CHECK-NEXT:      (then
- ;; CHECK-NEXT:       (drop
- ;; CHECK-NEXT:        (call $_printf_core
+ ;; CHECK-NEXT:      (i32.store
+ ;; CHECK-NEXT:       (local.get $9)
+ ;; CHECK-NEXT:       (local.get $4)
+ ;; CHECK-NEXT:      )
+ ;; CHECK-NEXT:      (i32.store
+ ;; CHECK-NEXT:       (local.tee $12
+ ;; CHECK-NEXT:        (i32.add
  ;; CHECK-NEXT:         (local.get $0)
- ;; CHECK-NEXT:         (i32.const 672)
- ;; CHECK-NEXT:         (local.get $2)
- ;; CHECK-NEXT:         (local.get $1)
- ;; CHECK-NEXT:         (local.get $7)
+ ;; CHECK-NEXT:         (i32.const 28)
  ;; CHECK-NEXT:        )
  ;; CHECK-NEXT:       )
+ ;; CHECK-NEXT:       (local.get $4)
  ;; CHECK-NEXT:      )
- ;; CHECK-NEXT:      (else
- ;; CHECK-NEXT:       (local.set $10
- ;; CHECK-NEXT:        (i32.load
- ;; CHECK-NEXT:         (local.tee $9
- ;; CHECK-NEXT:          (i32.add
- ;; CHECK-NEXT:           (local.get $0)
- ;; CHECK-NEXT:           (i32.const 44)
- ;; CHECK-NEXT:          )
- ;; CHECK-NEXT:         )
+ ;; CHECK-NEXT:      (i32.store
+ ;; CHECK-NEXT:       (local.tee $11
+ ;; CHECK-NEXT:        (i32.add
+ ;; CHECK-NEXT:         (local.get $0)
+ ;; CHECK-NEXT:         (i32.const 20)
  ;; CHECK-NEXT:        )
  ;; CHECK-NEXT:       )
- ;; CHECK-NEXT:       (i32.store
- ;; CHECK-NEXT:        (local.get $9)
- ;; CHECK-NEXT:        (local.get $4)
- ;; CHECK-NEXT:       )
- ;; CHECK-NEXT:       (i32.store
- ;; CHECK-NEXT:        (local.tee $12
- ;; CHECK-NEXT:         (i32.add
- ;; CHECK-NEXT:          (local.get $0)
- ;; CHECK-NEXT:          (i32.const 28)
- ;; CHECK-NEXT:         )
+ ;; CHECK-NEXT:       (local.get $4)
+ ;; CHECK-NEXT:      )
+ ;; CHECK-NEXT:      (i32.store
+ ;; CHECK-NEXT:       (local.get $5)
+ ;; CHECK-NEXT:       (i32.const 80)
+ ;; CHECK-NEXT:      )
+ ;; CHECK-NEXT:      (i32.store
+ ;; CHECK-NEXT:       (local.tee $13
+ ;; CHECK-NEXT:        (i32.add
+ ;; CHECK-NEXT:         (local.get $0)
+ ;; CHECK-NEXT:         (i32.const 16)
  ;; CHECK-NEXT:        )
- ;; CHECK-NEXT:        (local.get $4)
  ;; CHECK-NEXT:       )
- ;; CHECK-NEXT:       (i32.store
- ;; CHECK-NEXT:        (local.tee $11
- ;; CHECK-NEXT:         (i32.add
- ;; CHECK-NEXT:          (local.get $0)
- ;; CHECK-NEXT:          (i32.const 20)
- ;; CHECK-NEXT:         )
- ;; CHECK-NEXT:        )
+ ;; CHECK-NEXT:       (i32.add
  ;; CHECK-NEXT:        (local.get $4)
- ;; CHECK-NEXT:       )
- ;; CHECK-NEXT:       (i32.store
- ;; CHECK-NEXT:        (local.get $5)
  ;; CHECK-NEXT:        (i32.const 80)
  ;; CHECK-NEXT:       )
- ;; CHECK-NEXT:       (i32.store
- ;; CHECK-NEXT:        (local.tee $13
- ;; CHECK-NEXT:         (i32.add
- ;; CHECK-NEXT:          (local.get $0)
- ;; CHECK-NEXT:          (i32.const 16)
- ;; CHECK-NEXT:         )
- ;; CHECK-NEXT:        )
- ;; CHECK-NEXT:        (i32.add
- ;; CHECK-NEXT:         (local.get $4)
- ;; CHECK-NEXT:         (i32.const 80)
- ;; CHECK-NEXT:        )
- ;; CHECK-NEXT:       )
- ;; CHECK-NEXT:       (local.set $2
- ;; CHECK-NEXT:        (call $_printf_core
- ;; CHECK-NEXT:         (local.get $0)
- ;; CHECK-NEXT:         (i32.const 672)
- ;; CHECK-NEXT:         (local.get $2)
- ;; CHECK-NEXT:         (local.get $1)
- ;; CHECK-NEXT:         (local.get $7)
- ;; CHECK-NEXT:        )
+ ;; CHECK-NEXT:      )
+ ;; CHECK-NEXT:      (local.set $2
+ ;; CHECK-NEXT:       (call $_printf_core
+ ;; CHECK-NEXT:        (local.get $0)
+ ;; CHECK-NEXT:        (i32.const 672)
+ ;; CHECK-NEXT:        (local.get $2)
+ ;; CHECK-NEXT:        (local.get $1)
+ ;; CHECK-NEXT:        (local.get $7)
  ;; CHECK-NEXT:       )
- ;; CHECK-NEXT:       (if
- ;; CHECK-NEXT:        (local.get $10)
- ;; CHECK-NEXT:        (then
- ;; CHECK-NEXT:         (drop
- ;; CHECK-NEXT:          (call_indirect (type $FUNCSIG$iiii)
- ;; CHECK-NEXT:           (local.get $0)
- ;; CHECK-NEXT:           (i32.const 0)
- ;; CHECK-NEXT:           (i32.const 0)
- ;; CHECK-NEXT:           (i32.add
- ;; CHECK-NEXT:            (i32.and
- ;; CHECK-NEXT:             (i32.load offset=36
- ;; CHECK-NEXT:              (local.get $0)
- ;; CHECK-NEXT:             )
- ;; CHECK-NEXT:             (i32.const 7)
+ ;; CHECK-NEXT:      )
+ ;; CHECK-NEXT:      (if
+ ;; CHECK-NEXT:       (local.get $10)
+ ;; CHECK-NEXT:       (then
+ ;; CHECK-NEXT:        (drop
+ ;; CHECK-NEXT:         (call_indirect (type $FUNCSIG$iiii)
+ ;; CHECK-NEXT:          (local.get $0)
+ ;; CHECK-NEXT:          (i32.const 0)
+ ;; CHECK-NEXT:          (i32.const 0)
+ ;; CHECK-NEXT:          (i32.add
+ ;; CHECK-NEXT:           (i32.and
+ ;; CHECK-NEXT:            (i32.load offset=36
+ ;; CHECK-NEXT:             (local.get $0)
  ;; CHECK-NEXT:            )
- ;; CHECK-NEXT:            (i32.const 2)
+ ;; CHECK-NEXT:            (i32.const 7)
  ;; CHECK-NEXT:           )
+ ;; CHECK-NEXT:           (i32.const 2)
  ;; CHECK-NEXT:          )
  ;; CHECK-NEXT:         )
- ;; CHECK-NEXT:         (drop
- ;; CHECK-NEXT:          (i32.load
- ;; CHECK-NEXT:           (local.get $11)
- ;; CHECK-NEXT:          )
- ;; CHECK-NEXT:         )
- ;; CHECK-NEXT:         (i32.store
- ;; CHECK-NEXT:          (local.get $9)
- ;; CHECK-NEXT:          (local.get $10)
- ;; CHECK-NEXT:         )
- ;; CHECK-NEXT:         (i32.store
- ;; CHECK-NEXT:          (local.get $5)
- ;; CHECK-NEXT:          (i32.const 0)
- ;; CHECK-NEXT:         )
- ;; CHECK-NEXT:         (i32.store
- ;; CHECK-NEXT:          (local.get $13)
- ;; CHECK-NEXT:          (i32.const 0)
- ;; CHECK-NEXT:         )
- ;; CHECK-NEXT:         (i32.store
- ;; CHECK-NEXT:          (local.get $12)
- ;; CHECK-NEXT:          (i32.const 0)
- ;; CHECK-NEXT:         )
- ;; CHECK-NEXT:         (i32.store
+ ;; CHECK-NEXT:        )
+ ;; CHECK-NEXT:        (drop
+ ;; CHECK-NEXT:         (i32.load
  ;; CHECK-NEXT:          (local.get $11)
- ;; CHECK-NEXT:          (i32.const 0)
  ;; CHECK-NEXT:         )
  ;; CHECK-NEXT:        )
+ ;; CHECK-NEXT:        (i32.store
+ ;; CHECK-NEXT:         (local.get $9)
+ ;; CHECK-NEXT:         (local.get $10)
+ ;; CHECK-NEXT:        )
+ ;; CHECK-NEXT:        (i32.store
+ ;; CHECK-NEXT:         (local.get $5)
+ ;; CHECK-NEXT:         (i32.const 0)
+ ;; CHECK-NEXT:        )
+ ;; CHECK-NEXT:        (i32.store
+ ;; CHECK-NEXT:         (local.get $13)
+ ;; CHECK-NEXT:         (i32.const 0)
+ ;; CHECK-NEXT:        )
+ ;; CHECK-NEXT:        (i32.store
+ ;; CHECK-NEXT:         (local.get $12)
+ ;; CHECK-NEXT:         (i32.const 0)
+ ;; CHECK-NEXT:        )
+ ;; CHECK-NEXT:        (i32.store
+ ;; CHECK-NEXT:         (local.get $11)
+ ;; CHECK-NEXT:         (i32.const 0)
+ ;; CHECK-NEXT:        )
  ;; CHECK-NEXT:       )
  ;; CHECK-NEXT:      )
  ;; CHECK-NEXT:     )
- ;; CHECK-NEXT:     (i32.store
- ;; CHECK-NEXT:      (local.get $0)
- ;; CHECK-NEXT:      (i32.or
- ;; CHECK-NEXT:       (i32.load
- ;; CHECK-NEXT:        (local.get $0)
- ;; CHECK-NEXT:       )
- ;; CHECK-NEXT:       (i32.and
- ;; CHECK-NEXT:        (local.get $3)
- ;; CHECK-NEXT:        (i32.const 32)
- ;; CHECK-NEXT:       )
+ ;; CHECK-NEXT:    )
+ ;; CHECK-NEXT:    (i32.store
+ ;; CHECK-NEXT:     (local.get $0)
+ ;; CHECK-NEXT:     (i32.or
+ ;; CHECK-NEXT:      (i32.load
+ ;; CHECK-NEXT:       (local.get $0)
+ ;; CHECK-NEXT:      )
+ ;; CHECK-NEXT:      (i32.and
+ ;; CHECK-NEXT:       (local.get $3)
+ ;; CHECK-NEXT:       (i32.const 32)
  ;; CHECK-NEXT:      )
  ;; CHECK-NEXT:     )
- ;; CHECK-NEXT:     (i32.const 0)
  ;; CHECK-NEXT:    )
  ;; CHECK-NEXT:   )
  ;; CHECK-NEXT:  )
diff --git a/test/lit/passes/vacuum-intrinsics.wast b/test/lit/passes/vacuum-intrinsics.wast
index 8f62ea36d46..6e12be47f98 100644
--- a/test/lit/passes/vacuum-intrinsics.wast
+++ b/test/lit/passes/vacuum-intrinsics.wast
@@ -145,21 +145,23 @@
   )
 
   ;; CHECK:      (func $unused-fallthrough (type $0)
-  ;; CHECK-NEXT:  (drop
-  ;; CHECK-NEXT:   (if (result i32)
-  ;; CHECK-NEXT:    (block $condition (result i32)
-  ;; CHECK-NEXT:     (call $nop)
-  ;; CHECK-NEXT:     (call $call.without.effects
-  ;; CHECK-NEXT:      (ref.func $i)
-  ;; CHECK-NEXT:     )
+  ;; CHECK-NEXT:  (if
+  ;; CHECK-NEXT:   (block $condition (result i32)
+  ;; CHECK-NEXT:    (call $nop)
+  ;; CHECK-NEXT:    (call $call.without.effects
+  ;; CHECK-NEXT:     (ref.func $i)
   ;; CHECK-NEXT:    )
-  ;; CHECK-NEXT:    (then
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:   (then
+  ;; CHECK-NEXT:    (drop
   ;; CHECK-NEXT:     (block $ifTrue (result i32)
   ;; CHECK-NEXT:      (call $nop)
   ;; CHECK-NEXT:      (i32.const 0)
   ;; CHECK-NEXT:     )
   ;; CHECK-NEXT:    )
-  ;; CHECK-NEXT:    (else
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:   (else
+  ;; CHECK-NEXT:    (drop
   ;; CHECK-NEXT:     (block $ifFalse (result i32)
   ;; CHECK-NEXT:      (call $nop)
   ;; CHECK-NEXT:      (i32.const 0)
@@ -194,15 +196,17 @@
   )
 
   ;; CHECK:      (func $unused-fallthrough-bad-type (type $0)
-  ;; CHECK-NEXT:  (drop
-  ;; CHECK-NEXT:   (if (result (ref any))
-  ;; CHECK-NEXT:    (call $i)
-  ;; CHECK-NEXT:    (then
+  ;; CHECK-NEXT:  (if
+  ;; CHECK-NEXT:   (call $i)
+  ;; CHECK-NEXT:   (then
+  ;; CHECK-NEXT:    (drop
   ;; CHECK-NEXT:     (call $call.without.effects-ref
   ;; CHECK-NEXT:      (ref.func $ref)
   ;; CHECK-NEXT:     )
   ;; CHECK-NEXT:    )
-  ;; CHECK-NEXT:    (else
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:   (else
+  ;; CHECK-NEXT:    (drop
   ;; CHECK-NEXT:     (call $call.without.effects-ref
   ;; CHECK-NEXT:      (ref.func $ref)
   ;; CHECK-NEXT:     )
diff --git a/test/lit/passes/vacuum_all-features.wast b/test/lit/passes/vacuum_all-features.wast
index bdc313e7b1b..788ac197eb6 100644
--- a/test/lit/passes/vacuum_all-features.wast
+++ b/test/lit/passes/vacuum_all-features.wast
@@ -604,13 +604,15 @@
     )
   )
   ;; CHECK:      (func $if2drops (type $3) (result i32)
-  ;; CHECK-NEXT:  (drop
-  ;; CHECK-NEXT:   (if (result i32)
-  ;; CHECK-NEXT:    (call $if2drops)
-  ;; CHECK-NEXT:    (then
+  ;; CHECK-NEXT:  (if
+  ;; CHECK-NEXT:   (call $if2drops)
+  ;; CHECK-NEXT:   (then
+  ;; CHECK-NEXT:    (drop
   ;; CHECK-NEXT:     (call $if2drops)
   ;; CHECK-NEXT:    )
-  ;; CHECK-NEXT:    (else
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:   (else
+  ;; CHECK-NEXT:    (drop
   ;; CHECK-NEXT:     (call $if2drops)
   ;; CHECK-NEXT:    )
   ;; CHECK-NEXT:   )
@@ -1218,43 +1220,49 @@
  ;; CHECK-NEXT:    (return)
  ;; CHECK-NEXT:   )
  ;; CHECK-NEXT:  )
- ;; CHECK-NEXT:  (drop
- ;; CHECK-NEXT:   (if (result i32)
- ;; CHECK-NEXT:    (i32.eq
- ;; CHECK-NEXT:     (local.tee $0
- ;; CHECK-NEXT:      (call $_deflate
- ;; CHECK-NEXT:       (local.get $3)
- ;; CHECK-NEXT:      )
+ ;; CHECK-NEXT:  (if
+ ;; CHECK-NEXT:   (i32.eq
+ ;; CHECK-NEXT:    (local.tee $0
+ ;; CHECK-NEXT:     (call $_deflate
+ ;; CHECK-NEXT:      (local.get $3)
  ;; CHECK-NEXT:     )
- ;; CHECK-NEXT:     (i32.const 1)
  ;; CHECK-NEXT:    )
- ;; CHECK-NEXT:    (then
- ;; CHECK-NEXT:     (i32.store
- ;; CHECK-NEXT:      (local.get $1)
- ;; CHECK-NEXT:      (i32.load offset=20
- ;; CHECK-NEXT:       (local.get $3)
+ ;; CHECK-NEXT:    (i32.const 1)
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:   (then
+ ;; CHECK-NEXT:    (drop
+ ;; CHECK-NEXT:     (block (result i32)
+ ;; CHECK-NEXT:      (i32.store
+ ;; CHECK-NEXT:       (local.get $1)
+ ;; CHECK-NEXT:       (i32.load offset=20
+ ;; CHECK-NEXT:        (local.get $3)
+ ;; CHECK-NEXT:       )
  ;; CHECK-NEXT:      )
- ;; CHECK-NEXT:     )
- ;; CHECK-NEXT:     (local.set $0
- ;; CHECK-NEXT:      (call $_deflateEnd
+ ;; CHECK-NEXT:      (local.set $0
+ ;; CHECK-NEXT:       (call $_deflateEnd
+ ;; CHECK-NEXT:        (local.get $3)
+ ;; CHECK-NEXT:       )
+ ;; CHECK-NEXT:      )
+ ;; CHECK-NEXT:      (global.set $global$1
  ;; CHECK-NEXT:       (local.get $3)
  ;; CHECK-NEXT:      )
+ ;; CHECK-NEXT:      (i32.const 0)
  ;; CHECK-NEXT:     )
- ;; CHECK-NEXT:     (global.set $global$1
- ;; CHECK-NEXT:      (local.get $3)
- ;; CHECK-NEXT:     )
- ;; CHECK-NEXT:     (i32.const 0)
  ;; CHECK-NEXT:    )
- ;; CHECK-NEXT:    (else
- ;; CHECK-NEXT:     (drop
- ;; CHECK-NEXT:      (call $_deflateEnd
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:   (else
+ ;; CHECK-NEXT:    (drop
+ ;; CHECK-NEXT:     (block (result i32)
+ ;; CHECK-NEXT:      (drop
+ ;; CHECK-NEXT:       (call $_deflateEnd
+ ;; CHECK-NEXT:        (local.get $3)
+ ;; CHECK-NEXT:       )
+ ;; CHECK-NEXT:      )
+ ;; CHECK-NEXT:      (global.set $global$1
  ;; CHECK-NEXT:       (local.get $3)
  ;; CHECK-NEXT:      )
+ ;; CHECK-NEXT:      (i32.const 0)
  ;; CHECK-NEXT:     )
- ;; CHECK-NEXT:     (global.set $global$1
- ;; CHECK-NEXT:      (local.get $3)
- ;; CHECK-NEXT:     )
- ;; CHECK-NEXT:     (i32.const 0)
  ;; CHECK-NEXT:    )
  ;; CHECK-NEXT:   )
  ;; CHECK-NEXT:  )
@@ -1417,3 +1425,107 @@
   )
  )
 )
+
+(module
+  ;; Sinking drop into arms of concrete if
+  ;; CHECK:      (type $struct (struct (field (mut i32))))
+  (type $struct (struct (field (mut i32))))
+
+  ;; CHECK:      (type $1 (func (result i32)))
+
+  ;; CHECK:      (type $2 (func (param i32 i32 i32)))
+
+  ;; CHECK:      (type $3 (func (param i32)))
+
+  ;; CHECK:      (type $4 (func (param (ref null $struct) i32) (result (ref null $struct))))
+
+  ;; CHECK:      (type $5 (func (param i32 (ref null $struct))))
+
+  ;; CHECK:      (func $bar (type $1) (result i32)
+  ;; CHECK-NEXT:  (i32.const 1)
+  ;; CHECK-NEXT: )
+  (func $bar (result i32)
+    (i32.const 1)
+  )
+
+  ;; CHECK:      (func $pure-arms (type $2) (param $c i32) (param $x i32) (param $y i32)
+  ;; CHECK-NEXT:  (nop)
+  ;; CHECK-NEXT: )
+  (func $pure-arms (param $c i32) (param $x i32) (param $y i32)
+    (drop
+      (if (result i32)
+        (local.get $c)
+        (then (local.get $x))
+        (else (local.get $y))
+      )
+    )
+  )
+
+  ;; CHECK:      (func $effectful-arms (type $3) (param $c i32)
+  ;; CHECK-NEXT:  (if
+  ;; CHECK-NEXT:   (local.get $c)
+  ;; CHECK-NEXT:   (then
+  ;; CHECK-NEXT:    (drop
+  ;; CHECK-NEXT:     (call $bar)
+  ;; CHECK-NEXT:    )
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:   (else
+  ;; CHECK-NEXT:    (drop
+  ;; CHECK-NEXT:     (call $bar)
+  ;; CHECK-NEXT:    )
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:  )
+  ;; CHECK-NEXT: )
+  (func $effectful-arms (param $c i32)
+    (drop
+      (if (result i32)
+        (local.get $c)
+        (then (call $bar))
+        (else (call $bar))
+      )
+    )
+  )
+
+  ;; CHECK:      (func $put (type $4) (param $this (ref null $struct)) (param $v i32) (result (ref null $struct))
+  ;; CHECK-NEXT:  (struct.set $struct 0
+  ;; CHECK-NEXT:   (local.get $this)
+  ;; CHECK-NEXT:   (local.get $v)
+  ;; CHECK-NEXT:  )
+  ;; CHECK-NEXT:  (local.get $this)
+  ;; CHECK-NEXT: )
+  (func $put (param $this (ref null $struct)) (param $v i32) (result (ref null $struct))
+    (struct.set $struct 0 (local.get $this) (local.get $v))
+    (local.get $this)
+  )
+
+  ;; CHECK:      (func $gc-effectful-arms (type $5) (param $c i32) (param $b (ref null $struct))
+  ;; CHECK-NEXT:  (if
+  ;; CHECK-NEXT:   (local.get $c)
+  ;; CHECK-NEXT:   (then
+  ;; CHECK-NEXT:    (drop
+  ;; CHECK-NEXT:     (call $put
+  ;; CHECK-NEXT:      (local.get $b)
+  ;; CHECK-NEXT:      (i32.const 1)
+  ;; CHECK-NEXT:     )
+  ;; CHECK-NEXT:    )
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:   (else
+  ;; CHECK-NEXT:    (drop
+  ;; CHECK-NEXT:     (call $put
+  ;; CHECK-NEXT:      (local.get $b)
+  ;; CHECK-NEXT:      (i32.const 2)
+  ;; CHECK-NEXT:     )
+  ;; CHECK-NEXT:    )
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:  )
+  ;; CHECK-NEXT: )
+  (func $gc-effectful-arms (param $c i32) (param $b (ref null $struct))
+    (drop
+      (if (result (ref null $struct))
+        (local.get $c)
+        (then (call $put (local.get $b) (i32.const 1)))
+        (else (call $put (local.get $b) (i32.const 2)))
+      )
+    )
+  )
+)