%phi = phi i8* [ null, %entry ], [ %alloc, %coro.alloc ]
%frame = call i8* @llvm.coro.begin(token %id, i8* %phi)
+.. _coro.noop:
+
+'llvm.coro.noop' Intrinsic
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+::
+
+ declare i8* @llvm.coro.noop()
+
+Overview:
+"""""""""
+
+The '``llvm.coro.noop``' intrinsic returns an address of the coroutine frame of
+a coroutine that does nothing when resumed or destroyed.
+
+Arguments:
+""""""""""
+
+None
+
+Semantics:
+""""""""""
+
+This intrinsic is lowered to refer to a private constant coroutine frame. The
+resume and destroy handlers for this frame are empty functions that do nothing.
+Note that in different translation units llvm.coro.noop may return different pointers.
+
.. _coro.frame:
'llvm.coro.frame' Intrinsic
class Lowerer : public coro::LowererBase {
IRBuilder<> Builder;
PointerType *const AnyResumeFnPtrTy;
+ Constant *NoopCoro = nullptr;
void lowerResumeOrDestroy(CallSite CS, CoroSubFnInst::ResumeKind);
void lowerCoroPromise(CoroPromiseInst *Intrin);
void lowerCoroDone(IntrinsicInst *II);
+ void lowerCoroNoop(IntrinsicInst *II);
public:
Lowerer(Module &M)
II->eraseFromParent();
}
+void Lowerer::lowerCoroNoop(IntrinsicInst *II) {
+ if (!NoopCoro) {
+ LLVMContext &C = Builder.getContext();
+ Module &M = *II->getModule();
+
+ // Create a noop.frame struct type.
+ StructType *FrameTy = StructType::create(C, "NoopCoro.Frame");
+ auto *FramePtrTy = FrameTy->getPointerTo();
+ auto *FnTy = FunctionType::get(Type::getVoidTy(C), FramePtrTy,
+ /*IsVarArgs=*/false);
+ auto *FnPtrTy = FnTy->getPointerTo();
+ FrameTy->setBody({FnPtrTy, FnPtrTy});
+
+ // Create a Noop function that does nothing.
+ Function *NoopFn =
+ Function::Create(FnTy, GlobalValue::LinkageTypes::PrivateLinkage,
+ "NoopCoro.ResumeDestroy", &M);
+ NoopFn->setCallingConv(CallingConv::Fast);
+ auto *Entry = BasicBlock::Create(C, "entry", NoopFn);
+ ReturnInst::Create(C, Entry);
+
+ // Create a constant struct for the frame.
+ Constant* Values[] = {NoopFn, NoopFn};
+ Constant* NoopCoroConst = ConstantStruct::get(FrameTy, Values);
+ NoopCoro = new GlobalVariable(M, NoopCoroConst->getType(), /*isConstant=*/true,
+ GlobalVariable::PrivateLinkage, NoopCoroConst,
+ "NoopCoro.Frame.Const");
+ }
+
+ Builder.SetInsertPoint(II);
+ auto *NoopCoroVoidPtr = Builder.CreateBitCast(NoopCoro, Int8Ptr);
+ II->replaceAllUsesWith(NoopCoroVoidPtr);
+ II->eraseFromParent();
+}
+
// Prior to CoroSplit, calls to coro.begin needs to be marked as NoDuplicate,
// as CoroSplit assumes there is exactly one coro.begin. After CoroSplit,
// NoDuplicate attribute will be removed from coro.begin otherwise, it will
if (cast<CoroEndInst>(&I)->isFallthrough())
CS.setCannotDuplicate();
break;
+ case Intrinsic::coro_noop:
+ lowerCoroNoop(cast<IntrinsicInst>(&I));
+ break;
case Intrinsic::coro_id:
// Mark a function that comes out of the frontend that has a coro.id
// with a coroutine attribute.
// This pass has work to do only if we find intrinsics we are going to lower
// in the module.
bool doInitialization(Module &M) override {
- if (coro::declaresIntrinsics(M, {"llvm.coro.id", "llvm.coro.destroy",
- "llvm.coro.done", "llvm.coro.end",
- "llvm.coro.free", "llvm.coro.promise",
- "llvm.coro.resume", "llvm.coro.suspend"}))
+ if (coro::declaresIntrinsics(
+ M, {"llvm.coro.id", "llvm.coro.destroy", "llvm.coro.done",
+ "llvm.coro.end", "llvm.coro.noop", "llvm.coro.free",
+ "llvm.coro.promise", "llvm.coro.resume", "llvm.coro.suspend"}))
L = llvm::make_unique<Lowerer>(M);
return false;
}
static const char *const CoroIntrinsics[] = {
"llvm.coro.alloc", "llvm.coro.begin", "llvm.coro.destroy",
"llvm.coro.done", "llvm.coro.end", "llvm.coro.frame",
- "llvm.coro.free", "llvm.coro.id", "llvm.coro.param",
- "llvm.coro.promise", "llvm.coro.resume", "llvm.coro.save",
- "llvm.coro.size", "llvm.coro.subfn.addr", "llvm.coro.suspend",
+ "llvm.coro.free", "llvm.coro.id", "llvm.coro.noop",
+ "llvm.coro.param", "llvm.coro.promise", "llvm.coro.resume",
+ "llvm.coro.save", "llvm.coro.size", "llvm.coro.subfn.addr",
+ "llvm.coro.suspend",
};
return Intrinsic::lookupLLVMIntrinsicByName(CoroIntrinsics, Name) != -1;
}
-; Tests that CoroEarly pass correctly lowers coro.resume and coro.destroy
-; intrinsics.
+; Tests that CoroEarly pass correctly lowers coro.resume, coro.destroy
+; and other intrinsics managed by this pass.
; RUN: opt < %s -S -coro-early | FileCheck %s
+; CHECK: %NoopCoro.Frame = type { void (%NoopCoro.Frame*)*, void (%NoopCoro.Frame*)* }
+; CHECK: @NoopCoro.Frame.Const = private constant %NoopCoro.Frame { void (%NoopCoro.Frame*)* @NoopCoro.ResumeDestroy, void (%NoopCoro.Frame*)* @NoopCoro.ResumeDestroy }
+
; CHECK-LABEL: @callResume(
define void @callResume(i8* %hdl) {
; CHECK-NEXT: entry
cleanupret from %0 unwind to caller
}
+
+; CHECK-LABEL: @noop(
+define i8* @noop() {
+; CHECK-NEXT: entry
+entry:
+; CHECK-NEXT: ret i8* bitcast (%NoopCoro.Frame* @NoopCoro.Frame.Const to i8*)
+ %n = call i8* @llvm.coro.noop()
+ ret i8* %n
+}
+
+; CHECK-LABEL: define private fastcc void @NoopCoro.ResumeDestroy(%NoopCoro.Frame*) {
+; CHECK-NEXT: entry
+; CHECK-NEXT: ret void
+
+
declare void @llvm.coro.resume(i8*)
declare void @llvm.coro.destroy(i8*)
+declare i8* @llvm.coro.noop()