2 files changed, 108 insertions, 0 deletions
diff --git a/test/gtest/type-builder.cpp b/test/gtest/type-builder.cpp
index 443a7ee66..c0a27b229 100644
--- a/test/gtest/type-builder.cpp
+++ b/test/gtest/type-builder.cpp
@@ -273,6 +273,40 @@ TEST_F(TypeTest, InvalidFinalSupertype) {
   EXPECT_EQ(error->index, 1u);
 }
 
+TEST_F(TypeTest, InvalidSharedSupertype) {
+  TypeBuilder builder(2);
+  builder[0] = Struct{};
+  builder[1] = Struct{};
+  builder[0].setShared(true);
+  builder[1].setShared(false);
+  builder[1].subTypeOf(builder[0]);
+
+  auto result = builder.build();
+  EXPECT_FALSE(result);
+
+  const auto* error = result.getError();
+  ASSERT_TRUE(error);
+  EXPECT_EQ(error->reason, TypeBuilder::ErrorReason::InvalidSupertype);
+  EXPECT_EQ(error->index, 1u);
+}
+
+TEST_F(TypeTest, InvalidUnsharedSupertype) {
+  TypeBuilder builder(2);
+  builder[0] = Struct{};
+  builder[1] = Struct{};
+  builder[0].setShared(false);
+  builder[1].setShared(true);
+  builder[1].subTypeOf(builder[0]);
+
+  auto result = builder.build();
+  EXPECT_FALSE(result);
+
+  const auto* error = result.getError();
+  ASSERT_TRUE(error);
+  EXPECT_EQ(error->reason, TypeBuilder::ErrorReason::InvalidSupertype);
+  EXPECT_EQ(error->index, 1u);
+}
+
 TEST_F(TypeTest, ForwardReferencedChild) {
   TypeBuilder builder(3);
   builder.createRecGroup(0, 2);
diff --git a/test/lit/passes/type-merging-shared.wast b/test/lit/passes/type-merging-shared.wast
new file mode 100644
index 000000000..aefeccc3b
--- /dev/null
+++ b/test/lit/passes/type-merging-shared.wast
@@ -0,0 +1,74 @@
+;; NOTE: Assertions have been generated by update_lit_checks.py --all-items and should not be edited.
+;; RUN: foreach %s %t wasm-opt --closed-world --type-merging --remove-unused-types -all -S -o - | filecheck %s
+
+(module
+ ;; Shared and non-shared types are not merged.
+ ;; CHECK:      (rec
+ ;; CHECK-NEXT:  (type $C' (shared (func)))
+
+ ;; CHECK:       (type $B' (shared (array i8)))
+
+ ;; CHECK:       (type $B (array i8))
+
+ ;; CHECK:       (type $A' (shared (struct )))
+
+ ;; CHECK:       (type $A (struct ))
+ (type $A (struct))
+ (type $A' (shared (struct)))
+ (type $B (array i8))
+ (type $B' (shared (array i8)))
+ ;; CHECK:       (type $C (func))
+ (type $C (func))
+ (type $C' (shared (func)))
+
+ ;; CHECK:      (func $foo (type $C)
+ ;; CHECK-NEXT:  (local $a (ref null $A))
+ ;; CHECK-NEXT:  (local $a' (ref null $A'))
+ ;; CHECK-NEXT:  (local $b (ref null $B))
+ ;; CHECK-NEXT:  (local $b' (ref null $B'))
+ ;; CHECK-NEXT:  (local $c (ref null $C))
+ ;; CHECK-NEXT:  (local $c' (ref null $C'))
+ ;; CHECK-NEXT:  (nop)
+ ;; CHECK-NEXT: )
+ (func $foo
+  (local $a (ref null $A))
+  (local $a' (ref null $A'))
+  (local $b (ref null $B))
+  (local $b' (ref null $B'))
+  (local $c (ref null $C))
+  (local $c' (ref null $C'))
+ )
+)
+
+(module
+ ;; But two shared types can be merged.
+ ;; CHECK:      (rec
+ ;; CHECK-NEXT:  (type $B (shared (array i8)))
+
+ ;; CHECK:       (type $A (shared (struct )))
+ (type $A (shared (struct)))
+ (type $A' (shared (struct)))
+ (type $B (shared (array i8)))
+ (type $B' (shared (array i8)))
+ ;; CHECK:       (type $C (shared (func)))
+ (type $C (shared (func)))
+ (type $C' (shared (func)))
+
+ ;; CHECK:      (func $foo (type $C)
+ ;; CHECK-NEXT:  (local $a (ref null $A))
+ ;; CHECK-NEXT:  (local $a' (ref null $A))
+ ;; CHECK-NEXT:  (local $b (ref null $B))
+ ;; CHECK-NEXT:  (local $b' (ref null $B))
+ ;; CHECK-NEXT:  (local $c (ref null $C))
+ ;; CHECK-NEXT:  (local $c' (ref null $C))
+ ;; CHECK-NEXT:  (nop)
+ ;; CHECK-NEXT: )
+ (func $foo
+  (local $a (ref null $A))
+  (local $a' (ref null $A'))
+  (local $b (ref null $B))
+  (local $b' (ref null $B'))
+  (local $c (ref null $C))
+  (local $c' (ref null $C'))
+ )
+)