IRGen: ensure that ObjC sections match on all targets

lib/IRGen/GenClass.cpp

@@ -2108,10 +2108,14 @@ namespace {
                                      IGM.getPointerAlignment(),
                                      /*constant*/ true,
                                      llvm::GlobalVariable::PrivateLinkage);
+
       switch (IGM.TargetInfo.OutputObjectFormat) {
       case llvm::Triple::MachO:
         var->setSection("__DATA, __objc_const");
         break;
+      case llvm::Triple::COFF:
+        var->setSection(".data");
+        break;
       case llvm::Triple::ELF:
         var->setSection(".data");
         break;

lib/IRGen/GenDecl.cpp

@@ -770,31 +770,82 @@ void IRGenModule::addLazyConformances(NominalTypeDecl *Nominal) {
   }
 }
 
+std::string IRGenModule::GetObjCSectionName(StringRef Section,
+                                            StringRef MachOAttributes) {
+  assert(Section.substr(0, 2) == "__" && "expected the name to begin with __");
+
+  switch (TargetInfo.OutputObjectFormat) {
+  case llvm::Triple::UnknownObjectFormat:
+    llvm_unreachable("must know the object file format");
+  case llvm::Triple::MachO:
+    return MachOAttributes.empty()
+               ? ("__DATA," + Section).str()
+               : ("__DATA," + Section + "," + MachOAttributes).str();
+  case llvm::Triple::ELF:
+    return Section.substr(2).str();
+  case llvm::Triple::COFF:
+    return ("." + Section.substr(2) + "$B").str();
+  case llvm::Triple::Wasm:
+    error(SourceLoc(), "wasm is not a supported object file format");
+  }
+
+  llvm_unreachable("unexpected object file format");
+}
+
+void IRGenModule::SetCStringLiteralSection(llvm::GlobalVariable *GV,
+                                           ObjCLabelType Type) {
+  switch (TargetInfo.OutputObjectFormat) {
+  case llvm::Triple::UnknownObjectFormat:
+    llvm_unreachable("must know the object file format");
+  case llvm::Triple::MachO:
+    switch (Type) {
+    case ObjCLabelType::ClassName:
+      GV->setSection("__TEXT,__objc_classname,cstring_literals");
+      return;
+    case ObjCLabelType::MethodVarName:
+      GV->setSection("__TEXT,__objc_methname,cstring_literals");
+      return;
+    case ObjCLabelType::MethodVarType:
+      GV->setSection("__TEXT,__objc_methtype,cstring_literals");
+      return;
+    case ObjCLabelType::PropertyName:
+      GV->setSection("__TEXT,__cstring,cstring_literals");
+      return;
+    }
+  case llvm::Triple::ELF:
+    return;
+  case llvm::Triple::COFF:
+    return;
+  case llvm::Triple::Wasm:
+    error(SourceLoc(), "wasm is not a supported object file format");
+    return;
+  }
+
+  llvm_unreachable("unexpected object file format");
+}
+
 void IRGenModule::emitGlobalLists() {
   if (ObjCInterop) {
-    assert(TargetInfo.OutputObjectFormat == llvm::Triple::MachO);
     // Objective-C class references go in a variable with a meaningless
     // name but a magic section.
     emitGlobalList(*this, ObjCClasses, "objc_classes",
-                   "__DATA, __objc_classlist, regular, no_dead_strip",
-                   llvm::GlobalValue::InternalLinkage,
-                   Int8PtrTy,
-                   false);
+                   GetObjCSectionName("__objc_classlist",
+                                      "regular,no_dead_strip"),
+                   llvm::GlobalValue::InternalLinkage, Int8PtrTy, false);
+
     // So do categories.
     emitGlobalList(*this, ObjCCategories, "objc_categories",
-                   "__DATA, __objc_catlist, regular, no_dead_strip",
-                   llvm::GlobalValue::InternalLinkage,
-                   Int8PtrTy,
-                   false);
+                   GetObjCSectionName("__objc_catlist",
+                                      "regular,no_dead_strip"),
+                   llvm::GlobalValue::InternalLinkage, Int8PtrTy, false);
 
     // Emit nonlazily realized class references in a second magic section to make
     // sure they are realized by the Objective-C runtime before any instances
     // are allocated.
     emitGlobalList(*this, ObjCNonLazyClasses, "objc_non_lazy_classes",
-                   "__DATA, __objc_nlclslist, regular, no_dead_strip",
-                   llvm::GlobalValue::InternalLinkage,
-                   Int8PtrTy,
-                   false);
+                   GetObjCSectionName("__objc_nlclslist",
+                                      "regular,no_dead_strip"),
+                   llvm::GlobalValue::InternalLinkage, Int8PtrTy, false);
   }
 
   // @llvm.used
@@ -2422,7 +2473,8 @@ Address IRGenModule::getAddrOfObjCClassRef(ClassDecl *theClass) {
   // Define it lazily.
   if (auto global = dyn_cast<llvm::GlobalVariable>(addr)) {
     if (global->isDeclaration()) {
-      global->setSection("__DATA,__objc_classrefs,regular,no_dead_strip");
+      global->setSection(GetObjCSectionName("__objc_classrefs",
+                                            "regular,no_dead_strip"));
       global->setLinkage(llvm::GlobalVariable::PrivateLinkage);
       global->setExternallyInitialized(true);
       global->setInitializer(getAddrOfObjCClass(theClass, NotForDefinition));

lib/IRGen/GenMeta.cpp

@@ -3939,7 +3939,8 @@ void irgen::emitClassMetadata(IRGenModule &IGM, ClassDecl *classDecl,
   bool isIndirect = false;
 
   StringRef section{};
-  if (classDecl->isObjC())
+  if (classDecl->isObjC() &&
+      IGM.TargetInfo.OutputObjectFormat == llvm::Triple::MachO)
     section = "__DATA,__objc_data, regular";
 
   auto var = IGM.defineTypeMetadata(declaredType, isIndirect, isPattern,

lib/IRGen/GenObjC.cpp

@@ -329,7 +329,7 @@ llvm::Constant *IRGenModule::getAddrOfObjCMethodName(StringRef selector) {
                                          llvm::GlobalValue::PrivateLinkage,
                                          init,
                           llvm::Twine("\01L_selector_data(") + selector + ")");
-  global->setSection("__TEXT,__objc_methname,cstring_literals");
+  SetCStringLiteralSection(global, ObjCLabelType::MethodVarName);
   global->setAlignment(1);
   addCompilerUsedGlobal(global);
 
@@ -364,7 +364,8 @@ llvm::Constant *IRGenModule::getAddrOfObjCSelectorRef(StringRef selector) {
   global->setAlignment(getPointerAlignment().getValue());
 
   // This section name is magical for the Darwin static and dynamic linkers.
-  global->setSection("__DATA,__objc_selrefs,literal_pointers,no_dead_strip");
+  global->setSection(GetObjCSectionName("__objc_selrefs",
+                                        "literal_pointers,no_dead_strip"));
 
   // Make sure that this reference does not get optimized away.
   addCompilerUsedGlobal(global);
@@ -426,19 +427,19 @@ IRGenModule::getObjCProtocolGlobalVars(ProtocolDecl *proto) {
                                  + protocolName);
   protocolLabel->setAlignment(getPointerAlignment().getValue());
   protocolLabel->setVisibility(llvm::GlobalValue::HiddenVisibility);
-  protocolLabel->setSection("__DATA,__objc_protolist,coalesced,no_dead_strip");
-
+  protocolLabel->setSection(GetObjCSectionName("__objc_protolist",
+                                               "coalesced,no_dead_strip"));
+
   // Introduce a variable to reference the protocol.
-  auto *protocolRef
-    = new llvm::GlobalVariable(Module, Int8PtrTy,
-                               /*constant*/ false,
+  auto *protocolRef =
+      new llvm::GlobalVariable(Module, Int8PtrTy, /*constant*/ false,
                                llvm::GlobalValue::WeakAnyLinkage,
                                protocolRecord,
-                               llvm::Twine("\01l_OBJC_PROTOCOL_REFERENCE_$_")
-                                 + protocolName);
+                               llvm::Twine("\01l_OBJC_PROTOCOL_REFERENCE_$_") + protocolName);
   protocolRef->setAlignment(getPointerAlignment().getValue());
   protocolRef->setVisibility(llvm::GlobalValue::HiddenVisibility);
-  protocolRef->setSection("__DATA,__objc_protorefs,coalesced,no_dead_strip");
+  protocolRef->setSection(GetObjCSectionName("__objc_protorefs",
+                                             "coalesced,no_dead_strip"));
 
   ObjCProtocolPair pair{protocolRecord, protocolRef};
   ObjCProtocols.insert({proto, pair});

lib/IRGen/IRGenModule.h

@@ -587,6 +587,16 @@ class IRGenModule {
   Size getAtomicBoolSize() const { return AtomicBoolSize; }
   Alignment getAtomicBoolAlignment() const { return AtomicBoolAlign; }
 
+  enum class ObjCLabelType {
+    ClassName,
+    MethodVarName,
+    MethodVarType,
+    PropertyName,
+  };
+
+  std::string GetObjCSectionName(StringRef Section, StringRef MachOAttributes);
+  void SetCStringLiteralSection(llvm::GlobalVariable *GV, ObjCLabelType Type);
+
 private:
   Size PtrSize;
   Size AtomicBoolSize;

test/IRGen/Inputs/usr/include/ObjCInterop.h

@@ -0,0 +1,12 @@
+
+@protocol P
+@optional
+- (void)method;
+@end
+
+@interface I
+- (instancetype _Nonnull)init;
+@end
+
+I * _Nonnull f(I * _Nonnull);
+

test/IRGen/Inputs/usr/include/module.map

@@ -22,3 +22,7 @@ module Foundation {
 module CoreFoundation {
   header "BridgeTestCoreFoundation.h"
 }
+
+module ObjCInterop {
+  header "ObjCInterop.h"
+}

test/IRGen/objc-sections.swift

@@ -0,0 +1,47 @@
+// RUN: %swift -target x86_64-unknown-windows-msvc -parse-stdlib -enable-objc-interop -disable-objc-attr-requires-foundation-module -I %S/Inputs/usr/include -emit-ir %s -o - | %FileCheck %s -check-prefix CHECK-COFF
+// RUN: %swift -target x86_64-unknown-linux-gnu -parse-stdlib -enable-objc-interop -disable-objc-attr-requires-foundation-module -I %S/Inputs/usr/include -Xcc --sysroot=/var/empty -emit-ir %s -o - | %FileCheck %s -check-prefix CHECK-ELF
+// RUN: %swift -target x86_64-apple-ios -parse-stdlib -enable-objc-interop -disable-objc-attr-requires-foundation-module -I %S/Inputs/usr/include -emit-ir %s -o - | %FileCheck %s -check-prefix CHECK-MACHO
+
+import ObjCInterop
+
+@objc
+class C {
+}
+
+extension C : P {
+  public func method() {
+    f(I())
+  }
+}
+
+@objc_non_lazy_realization
+class D {
+}
+
+// CHECK-COFF-NOT: @_T04main1CCMf = {{.*}}, section "__DATA,__objc_data, regular"
+// CHECK-COFF: @"\01l_OBJC_LABEL_PROTOCOL_$_P" = {{.*}}, section ".objc_protolist$B"
+// CHECK-COFF: @"\01l_OBJC_PROTOCOL_REFERENCE_$_P" = {{.*}}, section ".objc_protorefs$B"
+// CHECK-COFF: @"OBJC_CLASS_REF_$_I" = {{.*}}, section ".objc_classrefs$B"
+// CHECK-COFF: @"\01L_selector(init)" = {{.*}}, section ".objc_selrefs$B"
+// CHECK-COFF: @objc_classes = {{.*}}, section ".objc_classlist$B"
+// CHECK-COFF: @objc_categories = {{.*}}, section ".objc_catlist$B"
+// CHECK-COFF: @objc_non_lazy_classes = {{.*}}, section ".objc_nlclslist$B"
+
+// CHECK-ELF-NOT: @_T04main1CCMf = {{.*}}, section "__DATA,__objc_data, regular"
+// CHECK-ELF: @"\01l_OBJC_LABEL_PROTOCOL_$_P" = {{.*}}, section "objc_protolist"
+// CHECK-ELF: @"\01l_OBJC_PROTOCOL_REFERENCE_$_P" = {{.*}}, section "objc_protorefs", align 8
+// CHECK-ELF: @"OBJC_CLASS_REF_$_I" = {{.*}}, section "objc_classrefs", align 8
+// CHECK-ELF: @"\01L_selector(init)" = {{.*}}, section "objc_selrefs"
+// CHECK-ELF: @objc_classes = {{.*}}, section "objc_classlist"
+// CHECK-ELF: @objc_categories = {{.*}}, section "objc_catlist"
+// CHECK-ELF: @objc_non_lazy_classes = {{.*}}, section "objc_nlclslist", align 8
+
+// CHECK-MACHO: @_T04main1CCMf = {{.*}}, section "__DATA,__objc_data, regular"
+// CHECK-MACHO: @"\01l_OBJC_LABEL_PROTOCOL_$_P" = {{.*}}, section "__DATA,__objc_protolist,coalesced,no_dead_strip"
+// CHECK-MACHO: @"\01l_OBJC_PROTOCOL_REFERENCE_$_P" = {{.*}}, section "__DATA,__objc_protorefs,coalesced,no_dead_strip"
+// CHECK-MACHO: @"OBJC_CLASS_REF_$_I" = {{.*}}, section "__DATA,__objc_classrefs,regular,no_dead_strip"
+// CHECK-MACHO: @"\01L_selector(init)" = {{.*}}, section "__DATA,__objc_selrefs,literal_pointers,no_dead_strip"
+// CHECK-MACHO: @objc_classes = {{.*}}, section "__DATA,__objc_classlist,regular,no_dead_strip"
+// CHECK-MACHO: @objc_categories = {{.*}}, section "__DATA,__objc_catlist,regular,no_dead_strip"
+// CHECK-MACHO: @objc_non_lazy_classes = {{.*}}, section "__DATA,__objc_nlclslist,regular,no_dead_strip"
+

test/IRGen/objc_subclass.swift

@@ -271,9 +271,9 @@
 // CHECK-64: ] }
 
 
-// CHECK: @objc_classes = internal global [2 x i8*] [i8* bitcast (%swift.type* @_T013objc_subclass10SwiftGizmoCN to i8*), i8* bitcast (%swift.type* @_T013objc_subclass11SwiftGizmo2CN to i8*)], section "__DATA, __objc_classlist, regular, no_dead_strip", align [[WORD_SIZE_IN_BYTES]]
+// CHECK: @objc_classes = internal global [2 x i8*] [i8* bitcast (%swift.type* @_T013objc_subclass10SwiftGizmoCN to i8*), i8* bitcast (%swift.type* @_T013objc_subclass11SwiftGizmo2CN to i8*)], section "__DATA,__objc_classlist,regular,no_dead_strip", align [[WORD_SIZE_IN_BYTES]]
 
-// CHECK: @objc_non_lazy_classes = internal global [1 x i8*] [i8* bitcast (%swift.type* @_T013objc_subclass11SwiftGizmo2CN to i8*)], section "__DATA, __objc_nlclslist, regular, no_dead_strip", align [[WORD_SIZE_IN_BYTES]]
+// CHECK: @objc_non_lazy_classes = internal global [1 x i8*] [i8* bitcast (%swift.type* @_T013objc_subclass11SwiftGizmo2CN to i8*)], section "__DATA,__objc_nlclslist,regular,no_dead_strip", align [[WORD_SIZE_IN_BYTES]]
 
 import Foundation
 import gizmo

test/IRGen/subclass.swift

@@ -35,7 +35,7 @@
 // CHECK:   i64 ([[B]]*)* @_T08subclass1BC1fSiyF,
 // CHECK:   [[A]]* ([[TYPE]]*)* @_T08subclass1AC1gACyFZ
 // CHECK: }>
-// CHECK: @objc_classes = internal global [2 x i8*] [i8* {{.*}} @_T08subclass1ACN {{.*}}, i8* {{.*}} @_T08subclass1BCN {{.*}}], section "__DATA, __objc_classlist, regular, no_dead_strip", align 8
+// CHECK: @objc_classes = internal global [2 x i8*] [i8* {{.*}} @_T08subclass1ACN {{.*}}, i8* {{.*}} @_T08subclass1BCN {{.*}}], section "__DATA,__objc_classlist,regular,no_dead_strip", align 8
 
 class A {
   var x = 0