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IRGen: emit emit_hop_to_executor instructions.
This basically means to create a suspension point and call the swift_task_switch runtime function. rdar://71099289
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6 files changed

+193
-3
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6 files changed

+193
-3
lines changed

‎include/swift/Runtime/RuntimeFunctions.def

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@@ -1518,6 +1518,16 @@ FUNCTION(TaskCreateFutureFunc,
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TaskContinuationFunctionPtrTy, SizeTy),
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ATTRS(NoUnwind, ArgMemOnly))
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// void swift_task_switch(AsyncTask *task,
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// ExecutorRef currentExecutor,
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// ExecutorRef newExecutor);
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FUNCTION(TaskSwitchFunc,
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swift_task_switch, SwiftCC,
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ConcurrencyAvailability,
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RETURNS(VoidTy),
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ARGS(SwiftTaskPtrTy, SwiftExecutorPtrTy, SwiftExecutorPtrTy),
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ATTRS(NoUnwind))
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// AutoDiffLinearMapContext *swift_autoDiffCreateLinearMapContext(size_t);
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FUNCTION(AutoDiffCreateLinearMapContext,
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swift_autoDiffCreateLinearMapContext, SwiftCC,

‎lib/IRGen/GenFunc.cpp

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@@ -2444,3 +2444,83 @@ IRGenFunction::createAsyncDispatchFn(const FunctionPointer &fnPtr,
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Builder.CreateRetVoid();
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return dispatch;
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}
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void IRGenFunction::emitSuspensionPoint(llvm::Value *toExecutor,
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llvm::Value *asyncResume) {
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// TODO: pointerauth
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// Setup the suspend point.
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SmallVector<llvm::Value *, 8> arguments;
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arguments.push_back(asyncResume);
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auto resumeProjFn = getOrCreateResumeFromSuspensionFn();
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arguments.push_back(
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Builder.CreateBitOrPointerCast(resumeProjFn, IGM.Int8PtrTy));
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llvm::Function *suspendFn = createAsyncSuspendFn();
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arguments.push_back(
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Builder.CreateBitOrPointerCast(suspendFn, IGM.Int8PtrTy));
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arguments.push_back(asyncResume);
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arguments.push_back(
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Builder.CreateBitOrPointerCast(toExecutor, getAsyncExecutor()->getType()));
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arguments.push_back(getAsyncTask());
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arguments.push_back(getAsyncExecutor());
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arguments.push_back(getAsyncContext());
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emitSuspendAsyncCall(arguments);
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}
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llvm::Function *IRGenFunction::getOrCreateResumeFromSuspensionFn() {
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auto name = "__swift_async_resume_get_context";
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return cast<llvm::Function>(IGM.getOrCreateHelperFunction(
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name, IGM.Int8PtrTy, {IGM.Int8PtrTy},
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[&](IRGenFunction &IGF) {
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auto &Builder = IGF.Builder;
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Builder.CreateRet(&*IGF.CurFn->arg_begin());
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},
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false /*isNoInline*/));
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}
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llvm::Function *IRGenFunction::createAsyncSuspendFn() {
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SmallVector<llvm::Type*, 8> argTys;
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argTys.push_back(IGM.Int8PtrTy); // Resume function.
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argTys.push_back(getAsyncExecutor()->getType()); // Executor to hop to.
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argTys.push_back(getAsyncTask()->getType());
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argTys.push_back(getAsyncExecutor()->getType());
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argTys.push_back(getAsyncContext()->getType());
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auto *suspendFnTy =
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llvm::FunctionType::get(IGM.VoidTy, argTys, false /*vaargs*/);
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StringRef name = "__swift_suspend_point";
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if (llvm::GlobalValue *F = IGM.Module.getNamedValue(name))
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return cast<llvm::Function>(F);
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llvm::Function *suspendFn =
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llvm::Function::Create(suspendFnTy, llvm::Function::InternalLinkage,
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name, &IGM.Module);
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suspendFn->setCallingConv(IGM.DefaultCC);
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suspendFn->setDoesNotThrow();
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IRGenFunction suspendIGF(IGM, suspendFn);
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if (IGM.DebugInfo)
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IGM.DebugInfo->emitArtificialFunction(suspendIGF, suspendFn);
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auto &Builder = suspendIGF.Builder;
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llvm::Value *resumeFunction = suspendFn->getArg(0);
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llvm::Value *targetExecutor = suspendFn->getArg(1);
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llvm::Value *task = suspendFn->getArg(2);
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llvm::Value *executor = suspendFn->getArg(3);
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llvm::Value *context = suspendFn->getArg(4);
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Alignment ptrAlign = IGM.getPointerAlignment();
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auto *resumeAddr = Builder.CreateStructGEP(task, 4);
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Builder.CreateStore(resumeFunction, Address(resumeAddr, ptrAlign));
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auto *contextAddr = Builder.CreateStructGEP(task, 5);
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Builder.CreateStore(context, Address(contextAddr, ptrAlign));
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auto *suspendCall = Builder.CreateCall(
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IGM.getTaskSwitchFuncFn(),
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{ task, executor, targetExecutor });
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suspendCall->setDoesNotThrow();
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suspendCall->setCallingConv(IGM.SwiftCC);
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suspendCall->setTailCall();
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Builder.CreateRetVoid();
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return suspendFn;
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}

‎lib/IRGen/IRGenFunction.h

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Original file line numberDiff line numberDiff line change
@@ -153,6 +153,10 @@ class IRGenFunction {
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FunctionPointer
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getFunctionPointerForResumeIntrinsic(llvm::Value *resumeIntrinsic);
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void emitSuspensionPoint(llvm::Value *toExecutor, llvm::Value *asyncResume);
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llvm::Function *getOrCreateResumeFromSuspensionFn();
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llvm::Function *createAsyncSuspendFn();
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private:
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void emitPrologue();
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void emitEpilogue();

‎lib/IRGen/IRGenSIL.cpp

Lines changed: 8 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -1091,9 +1091,7 @@ class IRGenSILFunction :
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void visitGetAsyncContinuationAddrInst(GetAsyncContinuationAddrInst *i);
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void visitAwaitAsyncContinuationInst(AwaitAsyncContinuationInst *i);
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void visitHopToExecutorInst(HopToExecutorInst *i) {
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//TODO(async)
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}
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void visitHopToExecutorInst(HopToExecutorInst *i);
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void visitKeyPathInst(KeyPathInst *I);
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@@ -5714,6 +5712,13 @@ void IRGenSILFunction::visitCheckedCastAddrBranchInst(
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getLoweredBB(i->getFailureBB()).bb);
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}
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void IRGenSILFunction::visitHopToExecutorInst(HopToExecutorInst *i) {
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llvm::Value *resumeFn = Builder.CreateIntrinsicCall(
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llvm::Intrinsic::coro_async_resume, {});
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emitSuspensionPoint(getLoweredSingletonExplosion(i->getOperand()), resumeFn);
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}
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void IRGenSILFunction::visitKeyPathInst(swift::KeyPathInst *I) {
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auto pattern = IGM.getAddrOfKeyPathPattern(I->getPattern(), I->getLoc());
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// Build up the argument vector to instantiate the pattern here.

‎test/IRGen/async/hop_to_executor.sil

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@@ -0,0 +1,37 @@
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// RUN: %target-swift-frontend -enable-experimental-concurrency -primary-file %s -module-name=test -disable-llvm-optzns -disable-swift-specific-llvm-optzns -emit-ir -sil-verify-all | %FileCheck %s
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// REQUIRES: concurrency
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sil_stage canonical
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import Builtin
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import Swift
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import _Concurrency
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final actor class MyActor {
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}
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// CHECK-LABEL: define{{.*}} void @test_simple(%swift.task* %0, %swift.executor* %1, %swift.context* %2)
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// CHECK: [[CTX:%[0-9]+]] = bitcast %swift.context* %2
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// CHECK: [[ACTOR_ADDR:%[0-9]+]] = getelementptr {{.*}} [[CTX]], i32 0, i32 6
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// CHECK: [[ACTOR:%[0-9]+]] = load %T4test7MyActorC*, %T4test7MyActorC** [[ACTOR_ADDR]]
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// CHECK: [[RESUME:%[0-9]+]] = call i8* @llvm.coro.async.resume()
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// CHECK: [[CAST_ACTOR:%[0-9]+]] = bitcast %T4test7MyActorC* [[ACTOR]] to %swift.executor*
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// CHECK: call {{.*}} @llvm.coro.suspend.async(i8* [[RESUME]], i8* bitcast (i8* (i8*)* @__swift_async_resume_get_context to i8*), i8* bitcast (void (i8*, %swift.executor*, %swift.task*, %swift.executor*, %swift.context*)* @__swift_suspend_point to i8*), i8* [[RESUME]], %swift.executor* [[CAST_ACTOR]], %swift.task* {{%[0-9]+}}, %swift.executor* {{%[0-9]+}}, %swift.context* {{%[0-9]+}})
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sil @test_simple : $@convention(method) @async (@guaranteed MyActor) -> () {
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bb0(%0 : $MyActor):
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hop_to_executor %0 : $MyActor
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%3 = tuple ()
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return %3 : $()
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}
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// CHECK-LABEL: define internal void @__swift_suspend_point(i8* %0, %swift.executor* %1, %swift.task* %2, %swift.executor* %3, %swift.context* %4)
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// CHECK: [[RESUME_ADDR:%[0-9]+]] = getelementptr inbounds %swift.task, %swift.task* %2, i32 0, i32 4
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// CHECK: store i8* %0, i8** [[RESUME_ADDR]]
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// CHECK: [[CTXT_ADDR:%[0-9]+]] = getelementptr inbounds %swift.task, %swift.task* %2, i32 0, i32 5
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// CHECK: store %swift.context* %4, %swift.context** [[CTXT_ADDR]]
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// CHECK: tail call swiftcc void @swift_task_switch(%swift.task* %2, %swift.executor* %3, %swift.executor* %1)
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// CHECK: ret void
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sil_vtable MyActor {
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}

‎test/IRGen/async/run-switch-executor.swift

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,54 @@
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// RUN: %empty-directory(%t)
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// RUN: %target-build-swift -Xfrontend -enable-experimental-concurrency %s -module-name main -o %t/main
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// RUN: %target-codesign %t/main
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// RUN: %target-run %t/main | %FileCheck %s
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// REQUIRES: executable_test
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// REQUIRES: concurrency
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// UNSUPPORTED: use_os_stdlib
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// UNSUPPORTED: CPU=arm64e
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// Currently this test just checks if nothing crashes.
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// TODO: also check if the current executor is the correct one.
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final actor class MyActor {
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var p: Int
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@inline(never)
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init(p: Int) {
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self.p = p
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}
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@inline(never)
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func callee() async -> Int {
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print("callee")
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return p
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}
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@inline(never)
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func testit() async -> Int {
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print("don't switch")
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let x = await callee()
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let otherActor = MyActor(p: 12)
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print("switch")
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let y = await otherActor.callee()
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print("switch back")
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return x + y + p
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}
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}
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// CHECK: run
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// CHECK: don't switch
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// CHECK: callee
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// CHECK: switch
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// CHECK: callee
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// CHECK: switch back
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// CHECK: 66
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runAsync {
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let a = MyActor(p: 27)
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print("run")
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await print(a.testit())
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}
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