IRGen: Default to weak hidden instead of internal linkage for objc metadata

This extends #39944 to apply to more objc metadata.

rdar://85037490

Author: aschwaighofer

lib/IRGen/GenClass.cpp

@@ -1343,7 +1343,8 @@ namespace {
       // };
 
       assert(fields.getNextOffsetFromGlobal() == size);
-      return buildGlobalVariable(fields, "_CATEGORY_", /*const*/ true);
+      return buildGlobalVariable(fields, "_CATEGORY_", /*const*/ true,
+                                 llvm::GlobalVariable::InternalLinkage);
     }
 
     llvm::Constant *emitProtocol() {
@@ -1503,7 +1504,8 @@ namespace {
       // statically. Otherwise, the ObjC runtime may slide the InstanceSize
       // based on changing base class layout.
       return buildGlobalVariable(fields, dataSuffix,
-                               /*const*/ forMeta || FieldLayout->isFixedSize());
+                               /*const*/ forMeta || FieldLayout->isFixedSize(),
+                               llvm::GlobalVariable::InternalLinkage);
     }
 
   private:
@@ -1768,12 +1770,8 @@ namespace {
         return null();
       }
 
-      auto *gv_as_const =  buildGlobalVariable(array, "_PROTOCOL_METHOD_TYPES_",
-                               /*const*/ true,
-                               /*likage*/ llvm::GlobalVariable::WeakAnyLinkage);
-      llvm::GlobalValue *gv = (llvm::GlobalValue *)gv_as_const;
-      gv->setVisibility(llvm::GlobalValue::HiddenVisibility);
-      return gv;
+      return buildGlobalVariable(array, "_PROTOCOL_METHOD_TYPES_",
+                                 /*const*/ true);
     }
 
     void buildExtMethodTypes(ConstantArrayBuilder &array,
@@ -2175,7 +2173,7 @@ namespace {
     template <class B>
     llvm::Constant *buildGlobalVariable(B &fields, StringRef nameBase, bool isConst,
                       llvm::GlobalValue::LinkageTypes linkage =
-                          llvm::GlobalVariable::InternalLinkage) {
+                          llvm::GlobalVariable::WeakAnyLinkage) {
       llvm::SmallString<64> nameBuffer;
       auto var =
         fields.finishAndCreateGlobal(Twine(nameBase) 
@@ -2186,6 +2184,9 @@ namespace {
                                      IGM.getPointerAlignment(),
                                      /*constant*/ true,
                                      linkage);
+      if (linkage == llvm::GlobalVariable::WeakAnyLinkage) {
+        var->setVisibility(llvm::GlobalValue::HiddenVisibility);
+      }
 
       switch (IGM.TargetInfo.OutputObjectFormat) {
       case llvm::Triple::MachO:

test/Concurrency/objc_async_protocol_irgen.swift

@@ -9,7 +9,7 @@ let anyObject: AnyObject = (MyAsyncProtocol.self as AnyObject) // or something l
 // Make sure we don't emit 2 copies of methods, due to a completion-handler
 // version and another due to an async based version.
 
-// CHECK-LABEL: @_PROTOCOL_INSTANCE_METHODS_MyAsyncProtocol = internal constant
+// CHECK-LABEL: @_PROTOCOL_INSTANCE_METHODS_MyAsyncProtocol = weak hidden constant
 // CHECK-SAME: selector_data(myAsyncMethod:)
 // CHECK-NOT: selector_data(myAsyncMethod:)
 // CHECK-SAME: align [[ALIGNMENT]]

test/IRGen/generic_casts.swift

@@ -8,22 +8,22 @@ import Foundation
 import gizmo
 
 // -- Protocol records for cast-to ObjC protocols
-// CHECK: @_PROTOCOL__TtP13generic_casts10ObjCProto1_ = internal constant
+// CHECK: @_PROTOCOL__TtP13generic_casts10ObjCProto1_ = weak hidden constant
 // CHECK: @"\01l_OBJC_LABEL_PROTOCOL_$__TtP13generic_casts10ObjCProto1_" = weak hidden global i8* bitcast ({{.*}} @_PROTOCOL__TtP13generic_casts10ObjCProto1_ to i8*), section {{"__DATA,__objc_protolist,coalesced,no_dead_strip"|"objc_protolist"|".objc_protolist\$B"}}
 // CHECK: @"\01l_OBJC_PROTOCOL_REFERENCE_$__TtP13generic_casts10ObjCProto1_" = weak hidden global i8* bitcast ({{.*}} @_PROTOCOL__TtP13generic_casts10ObjCProto1_ to i8*), section {{"__DATA,__objc_protorefs,coalesced,no_dead_strip"|"objc_protorefs"|".objc_protorefs\$B"}}
 
-// CHECK: @_PROTOCOL_NSRuncing = internal constant
+// CHECK: @_PROTOCOL_NSRuncing = weak hidden constant
 // CHECK: @"\01l_OBJC_LABEL_PROTOCOL_$_NSRuncing" = weak hidden global i8* bitcast ({{.*}} @_PROTOCOL_NSRuncing to i8*), section {{"__DATA,__objc_protolist,coalesced,no_dead_strip"|"objc_protolist"|".objc_protolist\$B"}}
 // CHECK: @"\01l_OBJC_PROTOCOL_REFERENCE_$_NSRuncing" = weak hidden global i8* bitcast ({{.*}} @_PROTOCOL_NSRuncing to i8*), section {{"__DATA,__objc_protorefs,coalesced,no_dead_strip"|"objc_protorefs"|".objc_protorefs\$B"}}
 
-// CHECK: @_PROTOCOLS__TtC13generic_casts10ObjCClass2 = internal constant { i64, [1 x i8*] } {
+// CHECK: @_PROTOCOLS__TtC13generic_casts10ObjCClass2 = weak hidden constant { i64, [1 x i8*] } {
 // CHECK:   i64 1, 
 // CHECK:   @_PROTOCOL__TtP13generic_casts10ObjCProto2_
 // CHECK: }
 
 // CHECK: @_DATA__TtC13generic_casts10ObjCClass2 = internal constant {{.*}} @_PROTOCOLS__TtC13generic_casts10ObjCClass2
 
-// CHECK: @_PROTOCOL_PROTOCOLS__TtP13generic_casts10ObjCProto2_ = internal constant { i64, [1 x i8*] } {
+// CHECK: @_PROTOCOL_PROTOCOLS__TtP13generic_casts10ObjCProto2_ = weak hidden constant { i64, [1 x i8*] } {
 // CHECK:   i64 1, 
 // CHECK:   @_PROTOCOL__TtP13generic_casts10ObjCProto1_
 // CHECK: }

test/IRGen/objc_async_metadata.swift

@@ -12,7 +12,7 @@ import Foundation
 // CHECK: [[ENCODE_ASYNC_STRING:@.*]] = private unnamed_addr constant [28 x i8] c"v24@0:8@?<v@?@\22NSString\22>16\00"
 // CHECK: [[ENCODE_ASYNC_THROWS_STRING:@.*]] = private unnamed_addr constant [38 x i8] c"v24@0:8@?<v@?@\22NSString\22@\22NSError\22>16\00"
 
-// CHECK: @_INSTANCE_METHODS__TtC19objc_async_metadata7MyClass = internal constant
+// CHECK: @_INSTANCE_METHODS__TtC19objc_async_metadata7MyClass = weak hidden constant
 // CHECK-SAME: methodWithCompletionHandler:
 // CHECK-SAME: [[ENCODE_ASYNC_STRING]]
 // CHECK-SAME: throwingMethodWithCompletionHandler:
@@ -23,7 +23,7 @@ class MyClass: NSObject {
 }
 
 // CHECK: [[ENCODE_ASYNC_STRING_PROTO:@.*]] = private unnamed_addr constant [15 x i8] c"v32@0:8@16@?24\00"
-// CHECK-LABEL: @_PROTOCOL_INSTANCE_METHODS__TtP19objc_async_metadata7MyProto_ = internal constant
+// CHECK-LABEL: @_PROTOCOL_INSTANCE_METHODS__TtP19objc_async_metadata7MyProto_ = weak hidden constant
 // CHECK-SAME: _selector_data(myProtoRequirement:completionHandler:)
 // CHECK-SAME: [15 x i8]* [[ENCODE_ASYNC_STRING_PROTO]]
 

test/IRGen/objc_attr_NSManaged.sil

@@ -17,12 +17,12 @@ import Foundation
 sil_vtable X {}
 
 // The getter/setter should not show up in the Objective-C metadata.
-// CHECK: @_INSTANCE_METHODS__TtC19objc_attr_NSManaged10SwiftGizmo = internal constant { i32, i32, [2 x { i8*, i8*, i8* }] } { i32 24, i32 2, {{.*}} @"\01L_selector_data(initWithBellsOn:)", {{.*}} @"\01L_selector_data(init)",
+// CHECK: @_INSTANCE_METHODS__TtC19objc_attr_NSManaged10SwiftGizmo = weak hidden constant { i32, i32, [2 x { i8*, i8*, i8* }] } { i32 24, i32 2, {{.*}} @"\01L_selector_data(initWithBellsOn:)", {{.*}} @"\01L_selector_data(init)",
 
 // CHECK: [[X:@[0-9]+]] = private unnamed_addr constant [2 x i8] c"x\00"
 
 // The property 'x' should show up in the Objective-C metadata.
-// CHECK: @_PROPERTIES__TtC19objc_attr_NSManaged10SwiftGizmo = internal constant { {{.*}}i32, i32, [1 x { i8*, i8* }] } { i32 16, i32 1, [1 x { i8*, i8* }] [{ i8*, i8* } { i8* getelementptr inbounds ([2 x i8], [2 x i8]* [[X]], i64 0, i64 0),
+// CHECK: @_PROPERTIES__TtC19objc_attr_NSManaged10SwiftGizmo = weak hidden constant { {{.*}}i32, i32, [1 x { i8*, i8* }] } { i32 16, i32 1, [1 x { i8*, i8* }] [{ i8*, i8* } { i8* getelementptr inbounds ([2 x i8], [2 x i8]* [[X]], i64 0, i64 0),
 
 // The getter/setter should not show up in the Swift metadata.
 // CHECK: @"$s19objc_attr_NSManaged10SwiftGizmoCMf" = internal global <{ {{.*}} }> <{ void (%T19objc_attr_NSManaged10SwiftGizmoC*)* {{.*}}@"$s19objc_attr_NSManaged10SwiftGizmoCfD{{(\.ptrauth)?}}"{{.*}}, i8**{{.*}} @"$sBOWV{{(.ptrauth)?(.)?[0-9]?}}"{{.*}}, {{.*}} @"OBJC_METACLASS_$__TtC19objc_attr_NSManaged10SwiftGizmo{{(.ptrauth)?}}"{{.*}}, %objc_class*{{.*}} @"OBJC_CLASS_$_Gizmo{{(.ptrauth)?}}"{{.*}}, %swift.opaque* @_objc_empty_cache, %swift.opaque* null,{{.*}}@_DATA__TtC19objc_attr_NSManaged10SwiftGizmo{{.*}}i64 {{1|2}}){{.*}}, i32 {{1|0}}, i32 0, i32 8, i16 7, i16 0, i32 96, i32 16, {{.*}}* @"$s19objc_attr_NSManaged10SwiftGizmoCMn{{(\.ptrauth)?}}"{{.*}}, i8* null }>

test/IRGen/objc_bridge.swift

@@ -11,7 +11,7 @@ import Foundation
 // CHECK: [[SETTER_SIGNATURE:@.*]] = private unnamed_addr constant [11 x i8] c"v24@0:8@16\00"
 // CHECK: [[DEALLOC_SIGNATURE:@.*]] = private unnamed_addr constant [8 x i8] c"v16@0:8\00"
 
-// CHECK: @_INSTANCE_METHODS__TtC11objc_bridge3Bas = internal constant { i32, i32, [17 x { i8*, i8*, i8* }] } {
+// CHECK: @_INSTANCE_METHODS__TtC11objc_bridge3Bas = weak hidden constant { i32, i32, [17 x { i8*, i8*, i8* }] } {
 // CHECK:   i32 24,
 // CHECK:   i32 17,
 // CHECK:   [17 x { i8*, i8*, i8* }] [
@@ -114,10 +114,10 @@ import Foundation
 // CHECK:   ]
 // CHECK: }, section "__DATA, {{.*}}", align 8
 
-// CHECK: @_PROPERTIES__TtC11objc_bridge3Bas = internal constant { i32, i32, [5 x { i8*, i8* }] } {
+// CHECK: @_PROPERTIES__TtC11objc_bridge3Bas = weak hidden constant { i32, i32, [5 x { i8*, i8* }] } {
 
 // CHECK: [[OBJC_BLOCK_PROPERTY:@.*]] = private unnamed_addr constant [8 x i8] c"T@?,N,C\00"
-// CHECK: @_PROPERTIES__TtC11objc_bridge21OptionalBlockProperty = internal constant {{.*}} [[OBJC_BLOCK_PROPERTY]]
+// CHECK: @_PROPERTIES__TtC11objc_bridge21OptionalBlockProperty = weak hidden constant {{.*}} [[OBJC_BLOCK_PROPERTY]]
 
 func getDescription(_ o: NSObject) -> String {
   return o.description

test/IRGen/objc_class_property.swift

@@ -6,10 +6,10 @@
 // class properties, so no ObjC property is reflected.
 
 // CHECK-NOT: @_PROPERTIES__TtC19objc_class_property7Smashed
-// CHECK: @_CLASS_METHODS__TtC19objc_class_property7Smashed = internal constant { i32, i32, [1 x { i8*, i8*, i8* }] } {
+// CHECK: @_CLASS_METHODS__TtC19objc_class_property7Smashed = weak hidden constant { i32, i32, [1 x { i8*, i8*, i8* }] } {
 // CHECK:   i8* getelementptr inbounds ([14 x i8], [14 x i8]* @"\01L_selector_data(sharedSmashed)"
 // CHECK-NOT: @_PROPERTIES__TtC19objc_class_property7Smashed
-// CHECK: @_INSTANCE_METHODS__TtC19objc_class_property7Smashed = internal constant { i32, i32, [1 x { i8*, i8*, i8* }] } {
+// CHECK: @_INSTANCE_METHODS__TtC19objc_class_property7Smashed = weak hidden constant { i32, i32, [1 x { i8*, i8*, i8* }] } {
 // CHECK:   i8* getelementptr inbounds ([5 x i8], [5 x i8]* @"\01L_selector_data(init)"
 // CHECK-NOT: @_PROPERTIES__TtC19objc_class_property7Smashed
 

test/IRGen/objc_extensions.swift

@@ -16,7 +16,7 @@ import objc_extension_base
 // CHECK: [[CATEGORY_NAME:@.*]] = private constant [16 x i8] c"objc_extensions\00"
 // CHECK: [[METHOD_TYPE:@.*]] = private unnamed_addr constant [8 x i8] c"v16@0:8\00"
 
-// CHECK-LABEL: @"_CATEGORY_PROTOCOLS_Gizmo_$_objc_extensions" = internal constant
+// CHECK-LABEL: @"_CATEGORY_PROTOCOLS_Gizmo_$_objc_extensions" = weak hidden constant
 // CHECK-SAME:   i64 1,
 // CHECK-SAME:   @_PROTOCOL__TtP15objc_extensions11NewProtocol_
 
@@ -84,7 +84,7 @@ extension Gizmo {
 class Hoozit : NSObject {
 }
 
-// CHECK-LABEL: @"_CATEGORY_INSTANCE_METHODS__TtC15objc_extensions6Hoozit_$_objc_extensions" = internal constant
+// CHECK-LABEL: @"_CATEGORY_INSTANCE_METHODS__TtC15objc_extensions6Hoozit_$_objc_extensions" = weak hidden constant
 // CHECK:   i32 24,
 // CHECK:   i32 1,
 // CHECK:   [1 x { i8*, i8*, i8* }] [{ i8*, i8*, i8* } {
@@ -94,7 +94,7 @@ class Hoozit : NSObject {
 // CHECK:   }]
 // CHECK: }, section "__DATA, {{.*}}", align 8
 
-// CHECK-LABEL: @"_CATEGORY_CLASS_METHODS__TtC15objc_extensions6Hoozit_$_objc_extensions" = internal constant
+// CHECK-LABEL: @"_CATEGORY_CLASS_METHODS__TtC15objc_extensions6Hoozit_$_objc_extensions" = weak hidden constant
 // CHECK:   i32 24,
 // CHECK:   i32 1,
 // CHECK:   [1 x { i8*, i8*, i8* }] [{ i8*, i8*, i8* } {
@@ -120,7 +120,7 @@ extension Hoozit {
 
 class SwiftOnly { }
 
-// CHECK-LABEL: @"_CATEGORY_INSTANCE_METHODS__TtC15objc_extensions9SwiftOnly_$_objc_extensions" = internal constant
+// CHECK-LABEL: @"_CATEGORY_INSTANCE_METHODS__TtC15objc_extensions9SwiftOnly_$_objc_extensions" = weak hidden constant
 // CHECK:   i32 24,
 // CHECK:   i32 1,
 // CHECK:   [1 x { i8*, i8*, i8* }] [{ i8*, i8*, i8* } {
@@ -175,7 +175,7 @@ class NSDogcow : NSObject {}
 
 // CHECK: [[NAME:@.*]] = private unnamed_addr constant [5 x i8] c"woof\00"
 // CHECK: [[ATTR:@.*]] = private unnamed_addr constant [7 x i8] c"Tq,N,D\00"
-// CHECK: @"_CATEGORY_PROPERTIES__TtC15objc_extensions8NSDogcow_$_objc_extensions" = internal constant {{.*}} [[NAME]], {{.*}} [[ATTR]], {{.*}}, section "__DATA, {{.*}}", align 8
+// CHECK: @"_CATEGORY_PROPERTIES__TtC15objc_extensions8NSDogcow_$_objc_extensions" = weak hidden constant {{.*}} [[NAME]], {{.*}} [[ATTR]], {{.*}}, section "__DATA, {{.*}}", align 8
 extension NSDogcow {
   @NSManaged var woof: Int
 }

test/IRGen/objc_int_encoding.sil

@@ -5,7 +5,7 @@
 // CHECK-64: [[INT_UINT_METHOD_ENCODING:@.*]] = private unnamed_addr constant {{.*}} c"Q24@0:8q16\00"
 // CHECK-32: [[INT_UINT_METHOD_ENCODING:@.*]] = private unnamed_addr constant {{.*}} c"I12@0:4i8\00"
 
-// CHECK: @_INSTANCE_METHODS__TtC17objc_int_encoding3Foo = internal constant {{.*}} [[SELECTOR]], {{.*}} [[INT_UINT_METHOD_ENCODING]], {{.*}} @"$s17objc_int_encoding3FooC3foo1xSuSi_tFTo{{(\.ptrauth)?}}"
+// CHECK: @_INSTANCE_METHODS__TtC17objc_int_encoding3Foo = weak hidden constant {{.*}} [[SELECTOR]], {{.*}} [[INT_UINT_METHOD_ENCODING]], {{.*}} @"$s17objc_int_encoding3FooC3foo1xSuSi_tFTo{{(\.ptrauth)?}}"
 
 sil_stage canonical
 

test/IRGen/objc_methods.swift

@@ -54,7 +54,7 @@ class ObjcDestructible: NSObject {
 // CHECK-ios: [[FAIL_SIGNATURE:@.*]] = private unnamed_addr constant [12 x i8] c"B24@0:8^@16\00"
 // CHECK-tvos: [[FAIL_SIGNATURE:@.*]] = private unnamed_addr constant [12 x i8] c"B24@0:8^@16\00"
 // CHECK-watchos: [[FAIL_SIGNATURE:@.*]] = private unnamed_addr constant [12 x i8] c"B24@0:8^@16\00"
-// CHECK: @_INSTANCE_METHODS__TtC12objc_methods3Foo = internal constant { {{.*}}] } {
+// CHECK: @_INSTANCE_METHODS__TtC12objc_methods3Foo = weak hidden constant { {{.*}}] } {
 // CHECK:   i32 24,
 // CHECK:   i32 10,
 // CHECK:   [10 x { i8*, i8*, i8* }] [{
@@ -84,7 +84,7 @@ class ObjcDestructible: NSObject {
 // CHECK-ios:     i8* bitcast (i1 (i8*, i8*, %4**)* @"$s12objc_methods3FooC4failyyKFTo" to i8*)
 // CHECK:   }]
 // CHECK: }, section "__DATA, {{.*}}", align 8
-// CHECK: @_INSTANCE_METHODS__TtC12objc_methods16ObjcDestructible = internal constant { {{.*}}] } {
+// CHECK: @_INSTANCE_METHODS__TtC12objc_methods16ObjcDestructible = weak hidden constant { {{.*}}] } {
 // CHECK:   i32 24,
 // CHECK:   i32 2,
 // CHECK:   [2 x { i8*, i8*, i8* }] [{