IRGen: Use linkonce_odr linkage for outlined copy_addr and destroy_addr

Now that they have unique mangling, we can get a small code size
savings for non-WMO builds.

Author: slavapestov

lib/IRGen/GenDecl.cpp

@@ -4319,9 +4319,6 @@ void IRGenModule::generateCallToOutlinedCopyAddr(
   llvm::Type *llvmType = dest->getType();
   auto *outlinedF =
       (this->*MethodToCall)(objectTI, llvmType, T, typeToMetadataVec);
-  llvm::Function *fn = dyn_cast<llvm::Function>(outlinedF);
-  assert(fn && "Expected llvm::Function");
-  fn->setLinkage(llvm::GlobalValue::InternalLinkage);
   llvm::CallInst *call = IGF.Builder.CreateCall(outlinedF, argsVec);
   call->setCallingConv(DefaultCC);
 }
@@ -4367,12 +4364,6 @@ void IRGenModule::generateCallToOutlinedDestroy(
       },
       true /*setIsNoInline*/);
 
-  if (T.hasArchetype()) {
-    llvm::Function *fn = dyn_cast<llvm::Function>(outlinedF);
-    assert(fn && "Expected llvm::Function");
-    fn->setLinkage(llvm::GlobalValue::InternalLinkage);
-  }
-
   llvm::CallInst *call = IGF.Builder.CreateCall(outlinedF, argsVec);
   call->setCallingConv(DefaultCC);
 }

test/IRGen/enum_resilience.swift

@@ -324,5 +324,5 @@ private enum ProtGenEnumWithSize<T: Prot> {
     case c2(s2: Size)
 }
 
-// CHECK-LABEL: define internal %T15enum_resilience19ProtGenEnumWithSize33_59077B69D65A4A3BEE0C93708067D5F0LLO* @"$S15enum_resilience19ProtGenEnumWithSize33_59077B69D65A4A3BEE0C93708067D5F0LLOyxGAA0C0RzlWOh"(%T15enum_resilience19ProtGenEnumWithSize
+// CHECK-LABEL: define linkonce_odr hidden %T15enum_resilience19ProtGenEnumWithSize33_59077B69D65A4A3BEE0C93708067D5F0LLO* @"$S15enum_resilience19ProtGenEnumWithSize33_59077B69D65A4A3BEE0C93708067D5F0LLOyxGAA0C0RzlWOh"(%T15enum_resilience19ProtGenEnumWithSize
 // CHECK:   ret %T15enum_resilience19ProtGenEnumWithSize33_59077B69D65A4A3BEE0C93708067D5F0LLO* %0

test/IRGen/existentials_objc.sil

@@ -42,7 +42,7 @@ bb0(%0 : $*Any, %1 : $*Any):
 // CHECK: call %Any* @"$SypWOb"(%Any* %1, %Any* %0)
 // CHECK-NEXT:    ret void
 
-// CHECK-DAG:   define internal %Any* @"$SypWOb"([[ANY:%Any]]*, %Any*)
+// CHECK-DAG:   define linkonce_odr hidden %Any* @"$SypWOb"([[ANY:%Any]]*, %Any*)
 // CHECK:         [[T0:%.*]] = getelementptr inbounds [[ANY]], [[ANY]]* [[SRC:%0]], i32 0, i32 1
 // CHECK-NEXT:    [[TYPE:%.*]] = load %swift.type*, %swift.type** [[T0]], align 8
 // CHECK-NEXT:    [[T0:%.*]] = getelementptr inbounds [[ANY]], [[ANY]]* [[DEST:%1]], i32 0, i32 1

test/IRGen/existentials_opaque_boxed.sil

@@ -443,7 +443,7 @@ bb0(%0 : $*Existential):
   return %t : $()
 }
 
-// CHECK: define{{( protected)?}} internal %T25existentials_opaque_boxed11ExistentialP* @"$S25existentials_opaque_boxed11Existential_pWOb"(%T25existentials_opaque_boxed11ExistentialP*, %T25existentials_opaque_boxed11ExistentialP*)
+// CHECK: define linkonce_odr hidden %T25existentials_opaque_boxed11ExistentialP* @"$S25existentials_opaque_boxed11Existential_pWOb"(%T25existentials_opaque_boxed11ExistentialP*, %T25existentials_opaque_boxed11ExistentialP*)
 // CHECK:   [[METADATA_ADDR:%.*]] = getelementptr inbounds %T25existentials_opaque_boxed11ExistentialP, %T25existentials_opaque_boxed11ExistentialP* %0, i32 0, i32 1
 // CHECK:   [[METADATA:%.*]] = load %swift.type*, %swift.type** [[METADATA_ADDR]]
 // CHECK:   [[LOCAL_METADATA_ADDR:%.*]] = getelementptr inbounds %T25existentials_opaque_boxed11ExistentialP, %T25existentials_opaque_boxed11ExistentialP* %1, i32 0, i32 1
@@ -480,7 +480,7 @@ bb0(%0 : $*Existential):
 // CHECK:   [[LOCAL:%.*]] = alloca %T25existentials_opaque_boxed11ExistentialP
 // CHECK:   call %T25existentials_opaque_boxed11ExistentialP* @"$S25existentials_opaque_boxed11Existential_pWOc"(%T25existentials_opaque_boxed11ExistentialP* %0, %T25existentials_opaque_boxed11ExistentialP* [[LOCAL]])
 // CHECK:   ret void
-// CHECK-LABEL: define{{( protected)?}} internal %T25existentials_opaque_boxed11ExistentialP* @"$S25existentials_opaque_boxed11Existential_pWOc"(%T25existentials_opaque_boxed11ExistentialP*, %T25existentials_opaque_boxed11ExistentialP*)
+// CHECK-LABEL: define linkonce_odr hidden %T25existentials_opaque_boxed11ExistentialP* @"$S25existentials_opaque_boxed11Existential_pWOc"(%T25existentials_opaque_boxed11ExistentialP*, %T25existentials_opaque_boxed11ExistentialP*)
 // CHECK:   [[TYPE_ADDR:%.*]] = getelementptr inbounds %T25existentials_opaque_boxed11ExistentialP, %T25existentials_opaque_boxed11ExistentialP* %0, i32 0, i32 1
 // CHECK:   [[ARG_TYPE:%.*]] = load %swift.type*, %swift.type** [[TYPE_ADDR]]
 // CHECK:   [[LOCAL_TYPE_ADDR:%.*]] = getelementptr inbounds %T25existentials_opaque_boxed11ExistentialP, %T25existentials_opaque_boxed11ExistentialP* %1, i32 0, i32 1