Add nonlazybind to objc_retain/objc_release when converting from intrinsics.

For performance reasons, clang set nonlazybind on these functions.  Now that we
are using intrinsics instead of runtime calls, we should set this attribute when
creating the runtime functions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349558 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/PreISelIntrinsicLowering.cpp b/lib/CodeGen/PreISelIntrinsicLowering.cpp
index cd15f6b7fcb9d163c53ed1767346f7419ae3b08a..3689dab2331064cb6b869f937b85cc7aadb79a01 100644 (file)
--- a/lib/CodeGen/PreISelIntrinsicLowering.cpp
+++ b/lib/CodeGen/PreISelIntrinsicLowering.cpp
@@ -57,7 +57,8 @@ static bool lowerLoadRelative(Function &F) {
   return Changed;
 }
 
-static bool lowerObjCCall(Function &F, const char *NewFn) {
+static bool lowerObjCCall(Function &F, const char *NewFn,
+                          bool setNonLazyBind = false) {
   if (F.use_empty())
     return false;
 
@@ -65,6 +66,12 @@ static bool lowerObjCCall(Function &F, const char *NewFn) {
   // program already contains a function with this name.
   Module *M = F.getParent();
   Constant* FCache = M->getOrInsertFunction(NewFn, F.getFunctionType());
+  
+  // If we have Native ARC, set nonlazybind attribute for these APIs for
+  // performance.
+  if (setNonLazyBind)
+    if (Function* Fn = dyn_cast<Function>(FCache))
+      Fn->addFnAttr(Attribute::NonLazyBind);
 
   for (auto I = F.use_begin(), E = F.use_end(); I != E;) {
     auto *CI = dyn_cast<CallInst>(I->getUser());
@@ -125,10 +132,10 @@ static bool lowerIntrinsics(Module &M) {
       Changed |= lowerObjCCall(F, "objc_moveWeak");
       break;
     case Intrinsic::objc_release:
-      Changed |= lowerObjCCall(F, "objc_release");
+      Changed |= lowerObjCCall(F, "objc_release", true);
       break;
     case Intrinsic::objc_retain:
-      Changed |= lowerObjCCall(F, "objc_retain");
+      Changed |= lowerObjCCall(F, "objc_retain", true);
       break;
     case Intrinsic::objc_retainAutorelease:
       Changed |= lowerObjCCall(F, "objc_retainAutorelease");

diff --git a/test/Transforms/PreISelIntrinsicLowering/objc-arc.ll b/test/Transforms/PreISelIntrinsicLowering/objc-arc.ll
index be852dfe37fe4ac21bfad00654b908285abbfde0..235ef65beee266a5295e302dd81aa84a0006b79c 100644 (file)
--- a/test/Transforms/PreISelIntrinsicLowering/objc-arc.ll
+++ b/test/Transforms/PreISelIntrinsicLowering/objc-arc.ll
@@ -279,3 +279,8 @@ declare i8* @llvm.objc.unretainedPointer(i8*)
 declare i8* @llvm.objc.retain.autorelease(i8*)
 declare i32 @llvm.objc.sync.enter(i8*)
 declare i32 @llvm.objc.sync.exit(i8*)
+
+; CHECK: declare void @objc_release(i8*) [[NLB:#[0-9]+]]
+; CHECK: declare i8* @objc_retain(i8*) [[NLB]]
+
+; CHECK: attributes [[NLB]] = { nonlazybind }