Fix direct comparisons with unshared basic heap types (#6845)

Audit the remaining ocurrences of `== HeapType::` and fix those that did
not handle shared types correctly. Add tests for some of the fixes;
others are NFC but clarify the code.

src/passes/Precompute.cpp

@@ -293,7 +293,7 @@ struct Precompute
             return;
           }
         } else if (singleValue.type.isRef() &&
-                   singleValue.type.getHeapType() == HeapType::func) {
+                   singleValue.type.getHeapType().isSignature()) {
           if (auto* r = curr->value->template dynCast<RefFunc>()) {
             r->func = singleValue.getFunc();
             r->finalize();

src/passes/StringLowering.cpp

@@ -291,8 +291,9 @@ struct StringLowering : public StringGathering {
       // singleton rec group.
       std::vector<Type> params, results;
       auto fix = [](Type t) {
-        if (t.isRef() && t.getHeapType() == HeapType::string) {
-          t = Type(HeapType::ext, t.getNullability());
+        if (t.isRef() && t.getHeapType().isMaybeShared(HeapType::string)) {
+          auto share = t.getHeapType().getShared();
+          t = Type(HeapTypes::ext.getBasic(share), t.getNullability());
         }
         return t;
       };
@@ -495,9 +496,13 @@ struct StringLowering : public StringGathering {
       void noteSubtype(Expression* a, Type b) {
         // This is the case we care about: if |a| is a null that must be a
         // subtype of ext then we fix that up.
-        if (b.isRef() && b.getHeapType().getTop() == HeapType::ext) {
+        if (!b.isRef()) {
+          return;
+        }
+        HeapType top = b.getHeapType().getTop();
+        if (top.isMaybeShared(HeapType::ext)) {
           if (auto* null = a->dynCast<RefNull>()) {
-            null->finalize(HeapType::noext);
+            null->finalize(HeapTypes::noext.getBasic(top.getShared()));
           }
         }
       }

src/tools/wasm-ctor-eval.cpp

@@ -834,11 +834,13 @@ struct CtorEvalExternalInterface : EvallingModuleRunner::ExternalInterface {
     // logic here, we save the original (possible externalized) value, and then
     // look at the internals from here on out.
     Literal original = value;
-    if (value.type.isRef() && value.type.getHeapType() == HeapType::ext) {
+    if (value.type.isRef() &&
+        value.type.getHeapType().isMaybeShared(HeapType::ext)) {
       value = value.internalize();
 
       // We cannot serialize truly external things, only data and i31s.
-      assert(value.isData() || value.type.getHeapType() == HeapType::i31);
+      assert(value.isData() ||
+             value.type.getHeapType().isMaybeShared(HeapType::i31));
     }
 
     // GC data (structs and arrays) must be handled with the special global-
@@ -920,7 +922,7 @@ struct CtorEvalExternalInterface : EvallingModuleRunner::ExternalInterface {
     Expression* ret = builder.makeGlobalGet(definingGlobalName, value.type);
     if (original != value) {
       // The original is externalized.
-      assert(original.type.getHeapType() == HeapType::ext);
+      assert(original.type.getHeapType().isMaybeShared(HeapType::ext));
       ret = builder.makeRefAs(ExternConvertAny, ret);
     }
     return ret;

src/wasm-builder.h

@@ -1387,8 +1387,10 @@ class Builder {
     if (curr->type.isNullable() && curr->type.isNull()) {
       return ExpressionManipulator::refNull(curr, curr->type);
     }
-    if (curr->type.isRef() && curr->type.getHeapType() == HeapType::i31) {
-      Expression* ret = makeRefI31(makeConst(0));
+    if (curr->type.isRef() &&
+        curr->type.getHeapType().isMaybeShared(HeapType::i31)) {
+      Expression* ret =
+        makeRefI31(makeConst(0), curr->type.getHeapType().getShared());
       if (curr->type.isNullable()) {
         // To keep the type identical, wrap it in a block that adds nullability.
         ret = makeBlock({ret}, curr->type);

src/wasm/literal.cpp

@@ -444,7 +444,7 @@ bool Literal::operator==(const Literal& other) const {
       return gcData == other.gcData;
     }
     assert(type.getHeapType().isBasic());
-    if (type.getHeapType().getBasic(Unshared) == HeapType::i31) {
+    if (type.getHeapType().isMaybeShared(HeapType::i31)) {
       return i32 == other.i32;
     }
     WASM_UNREACHABLE("unexpected type");

src/wasm/wasm-validator.cpp

@@ -2769,7 +2769,7 @@ void FunctionValidator::visitCallRef(CallRef* curr) {
     getModule()->features.hasGC(), curr, "call_ref requires gc [--enable-gc]");
   if (curr->target->type == Type::unreachable ||
       (curr->target->type.isRef() &&
-       curr->target->type.getHeapType() == HeapType::nofunc)) {
+       curr->target->type.getHeapType().isMaybeShared(HeapType::nofunc))) {
     return;
   }
   if (shouldBeTrue(curr->target->type.isFunction(),

test/lit/ctor-eval/extern.wast

@@ -1,18 +1,19 @@
 ;; NOTE: Assertions have been generated by update_lit_checks.py --all-items and should not be edited.
-;; RUN: wasm-ctor-eval %s --ctors=test1,test2,test3 --kept-exports=test1,test2,test3 --quiet -all -S -o - | filecheck %s
+;; RUN: wasm-ctor-eval %s --ctors=test1,test1-shared,test2,test2-shared,test3,test3-shared \
+;; RUN:     --kept-exports=test1,test1-shared,test2,test2-shared,test3,test3-shared --quiet -all -S -o - | filecheck %s
 
 (module
  ;; CHECK:      (type $array (array (mut i8)))
  (type $array (array (mut i8)))
+ ;; CHECK:      (type $shared-array (shared (array (mut i8))))
+ (type $shared-array (shared (array (mut i8))))
 
  ;; CHECK:      (type $struct (struct (field externref)))
  (type $struct (struct (field externref)))
+ ;; CHECK:      (type $shared-struct (shared (struct (field (ref null (shared extern))))))
+ (type $shared-struct (shared (struct (field (ref null (shared extern))))))
 
- (export "test1" (func $test1))
- (export "test2" (func $test2))
- (export "test3" (func $test3))
-
- (func $test1 (result externref)
+ (func $test1 (export "test1") (result externref)
   ;; This will remain almost the same, even though we eval it, since the
   ;; serialization of an externalized i31 is what is written here. But the add
   ;; will be evalled out.
@@ -26,7 +27,19 @@
   )
  )
 
- (func $test2 (result externref)
+ (func $test1-shared (export "test1-shared") (result (ref null (shared extern)))
+  ;; Same as above, but now the i31 is shared.
+  (extern.convert_any
+   (ref.i31_shared
+    (i32.add
+     (i32.const 41)
+     (i32.const 1)
+    )
+   )
+  )
+ )
+
+ (func $test2 (export "test2") (result externref)
   ;; This will be evalled into an externalization of a global.get.
   (extern.convert_any
    (array.new_fixed $array 3
@@ -37,7 +50,18 @@
   )
  )
 
- (func $test3 (result anyref)
+ (func $test2-shared (export "test2-shared") (result (ref null (shared extern)))
+  ;; Same as above, but now the array is shared.
+  (extern.convert_any
+   (array.new_fixed $shared-array 3
+    (i32.const 1)
+    (i32.const 2)
+    (i32.const 3)
+   )
+  )
+ )
+
+ (func $test3 (export "test3") (result anyref)
   ;; This will add a global that contains an externalization operation.
   (struct.new $struct
    (extern.convert_any
@@ -47,46 +71,99 @@
    )
   )
  )
+
+ (func $test3-shared (export "test3-shared") (result (ref null (shared any)))
+  ;; Same as above, but now the struct and i31 are shared.
+  (struct.new $shared-struct
+   (extern.convert_any
+    (ref.i31_shared
+     (i32.const 1)
+    )
+   )
+  )
+ )
 )
 
-;; CHECK:      (type $2 (func (result externref)))
+;; CHECK:      (type $4 (func (result externref)))
+
+;; CHECK:      (type $5 (func (result (ref null (shared extern)))))
+
+;; CHECK:      (type $6 (func (result anyref)))
 
-;; CHECK:      (type $3 (func (result anyref)))
+;; CHECK:      (type $7 (func (result (ref null (shared any)))))
 
 ;; CHECK:      (global $ctor-eval$global (ref $array) (array.new_fixed $array 3
 ;; CHECK-NEXT:  (i32.const 1)
 ;; CHECK-NEXT:  (i32.const 2)
 ;; CHECK-NEXT:  (i32.const 3)
 ;; CHECK-NEXT: ))
 
-;; CHECK:      (global $ctor-eval$global_1 (ref $struct) (struct.new $struct
+;; CHECK:      (global $ctor-eval$global_1 (ref $shared-array) (array.new_fixed $shared-array 3
+;; CHECK-NEXT:  (i32.const 1)
+;; CHECK-NEXT:  (i32.const 2)
+;; CHECK-NEXT:  (i32.const 3)
+;; CHECK-NEXT: ))
+
+;; CHECK:      (global $ctor-eval$global_2 (ref $struct) (struct.new $struct
 ;; CHECK-NEXT:  (extern.convert_any
 ;; CHECK-NEXT:   (ref.i31
 ;; CHECK-NEXT:    (i32.const 1)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: ))
 
-;; CHECK:      (export "test1" (func $test1_3))
+;; CHECK:      (global $ctor-eval$global_3 (ref $shared-struct) (struct.new $shared-struct
+;; CHECK-NEXT:  (extern.convert_any
+;; CHECK-NEXT:   (ref.i31_shared
+;; CHECK-NEXT:    (i32.const 1)
+;; CHECK-NEXT:   )
+;; CHECK-NEXT:  )
+;; CHECK-NEXT: ))
+
+;; CHECK:      (export "test1" (func $test1_6))
+
+;; CHECK:      (export "test1-shared" (func $test1-shared_7))
+
+;; CHECK:      (export "test2" (func $test2_8))
 
-;; CHECK:      (export "test2" (func $test2_4))
+;; CHECK:      (export "test2-shared" (func $test2-shared_9))
 
-;; CHECK:      (export "test3" (func $test3_5))
+;; CHECK:      (export "test3" (func $test3_10))
 
-;; CHECK:      (func $test1_3 (type $2) (result externref)
+;; CHECK:      (export "test3-shared" (func $test3-shared_11))
+
+;; CHECK:      (func $test1_6 (type $4) (result externref)
 ;; CHECK-NEXT:  (extern.convert_any
 ;; CHECK-NEXT:   (ref.i31
 ;; CHECK-NEXT:    (i32.const 42)
 ;; CHECK-NEXT:   )
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 
-;; CHECK:      (func $test2_4 (type $2) (result externref)
+;; CHECK:      (func $test1-shared_7 (type $5) (result (ref null (shared extern)))
+;; CHECK-NEXT:  (extern.convert_any
+;; CHECK-NEXT:   (ref.i31_shared
+;; CHECK-NEXT:    (i32.const 42)
+;; CHECK-NEXT:   )
+;; CHECK-NEXT:  )
+;; CHECK-NEXT: )
+
+;; CHECK:      (func $test2_8 (type $4) (result externref)
 ;; CHECK-NEXT:  (extern.convert_any
 ;; CHECK-NEXT:   (global.get $ctor-eval$global)
 ;; CHECK-NEXT:  )
 ;; CHECK-NEXT: )
 
-;; CHECK:      (func $test3_5 (type $3) (result anyref)
-;; CHECK-NEXT:  (global.get $ctor-eval$global_1)
+;; CHECK:      (func $test2-shared_9 (type $5) (result (ref null (shared extern)))
+;; CHECK-NEXT:  (extern.convert_any
+;; CHECK-NEXT:   (global.get $ctor-eval$global_1)
+;; CHECK-NEXT:  )
+;; CHECK-NEXT: )
+
+;; CHECK:      (func $test3_10 (type $6) (result anyref)
+;; CHECK-NEXT:  (global.get $ctor-eval$global_2)
+;; CHECK-NEXT: )
+
+;; CHECK:      (func $test3-shared_11 (type $7) (result (ref null (shared any)))
+;; CHECK-NEXT:  (global.get $ctor-eval$global_3)
 ;; CHECK-NEXT: )

test/lit/passes/precompute-ref-func.wast

@@ -0,0 +1,36 @@
+;; NOTE: Assertions have been generated by update_lit_checks.py --all-items and should not be edited.
+;; RUN: wasm-opt %s -all --precompute -S -o - | filecheck %s
+
+(module
+  ;; CHECK:      (type $0 (func (result funcref)))
+
+  ;; CHECK:      (type $shared-func (shared (func (result (ref null (shared func))))))
+  (type $shared-func (shared (func (result (ref null (shared func))))))
+  ;; CHECK:      (elem declare func $test $test-shared)
+
+  ;; CHECK:      (func $test (type $0) (result funcref)
+  ;; CHECK-NEXT:  (return
+  ;; CHECK-NEXT:   (ref.func $test)
+  ;; CHECK-NEXT:  )
+  ;; CHECK-NEXT: )
+  (func $test (result funcref)
+    (block
+      (return
+        (ref.func $test)
+      )
+    )
+  )
+
+  ;; CHECK:      (func $test-shared (type $shared-func) (result (ref null (shared func)))
+  ;; CHECK-NEXT:  (return
+  ;; CHECK-NEXT:   (ref.func $test-shared)
+  ;; CHECK-NEXT:  )
+  ;; CHECK-NEXT: )
+  (func $test-shared (type $shared-func)
+    (block
+      (return
+        (ref.func $test-shared)
+      )
+    )
+  )
+)