[IRGen] Only use a stub for swift_coroFrameAlloc when we need it

include/swift/AST/FeatureAvailability.def

@@ -82,6 +82,7 @@ FEATURE(ValueGenericType,                               (6, 2))
 FEATURE(InitRawStructMetadata2,                         (6, 2))
 FEATURE(CustomGlobalExecutors,                          (6, 2))
 FEATURE(TaskExecutor,                                   (6, 2))
+FEATURE(TypedCoroAlloc,                                 (6, 2))
 
 FEATURE(Differentiation,                                FUTURE)
 FEATURE(ClearSensitive,                                 FUTURE)

include/swift/Runtime/RuntimeFunctions.def

@@ -2059,7 +2059,8 @@ FUNCTION(Free, c, free, C_CC, AlwaysAvailable,
          NO_ATTRS,
          EFFECT(RuntimeEffect::Deallocating),
          UNKNOWN_MEMEFFECTS)
-FUNCTION(CoroFrameAlloc, Swift, swift_coroFrameAlloc, C_CC, AlwaysAvailable,
+FUNCTION(CoroFrameAlloc, Swift, swift_coroFrameAlloc, C_CC,
+         TypedCoroAllocAvailability,
          RETURNS(Int8PtrTy),
          ARGS(SizeTy, Int64Ty),
          NO_ATTRS,

lib/Driver/DarwinToolChains.cpp

@@ -366,6 +366,8 @@ toolchains::Darwin::addArgsToLinkStdlib(ArgStringList &Arguments,
       runtimeCompatibilityVersion = llvm::VersionTuple(5, 8);
     } else if (value == "6.0") {
       runtimeCompatibilityVersion = llvm::VersionTuple(6, 0);
+    } else if (value == "6.2") {
+      runtimeCompatibilityVersion = llvm::VersionTuple(6, 2);
     } else if (value == "none") {
       runtimeCompatibilityVersion = std::nullopt;
     } else {

lib/Frontend/CompilerInvocation.cpp

@@ -3699,6 +3699,8 @@ static bool ParseIRGenArgs(IRGenOptions &Opts, ArgList &Args,
         runtimeCompatibilityVersion = llvm::VersionTuple(5, 8);
       } else if (version == "6.0") {
         runtimeCompatibilityVersion = llvm::VersionTuple(6, 0);
+      } else if (version == "6.2") {
+        runtimeCompatibilityVersion = llvm::VersionTuple(6, 2);
       } else {
         Diags.diagnose(SourceLoc(), diag::error_invalid_arg_value,
                        versionArg->getAsString(Args), version);

lib/IRGen/GenFunc.cpp

@@ -863,15 +863,20 @@ CanType irgen::getArgumentLoweringType(CanType type, SILParameterInfo paramInfo,
 }
 
 llvm::Constant *irgen::getCoroFrameAllocStubFn(IRGenModule &IGM) {
+  // If the coroutine allocation function is always available, call it directly.
+  auto coroAllocPtr = IGM.getCoroFrameAllocFn();
+  auto coroAllocFn = dyn_cast<llvm::Function>(coroAllocPtr);
+  if (coroAllocFn->getLinkage() != llvm::GlobalValue::ExternalWeakLinkage)
+    return coroAllocFn;
+
+  // Otherwise, create a stub function to call it when available, or malloc
+  // when it isn't.
   return IGM.getOrCreateHelperFunction(
     "__swift_coroFrameAllocStub", IGM.Int8PtrTy,
     {IGM.SizeTy, IGM.Int64Ty},
     [&](IRGenFunction &IGF) {
       auto parameters = IGF.collectParameters();
       auto *size = parameters.claimNext();
-      auto coroAllocPtr = IGF.IGM.getCoroFrameAllocFn();
-      auto coroAllocFn = dyn_cast<llvm::Function>(coroAllocPtr);
-      coroAllocFn->setLinkage(llvm::GlobalValue::ExternalWeakLinkage);
       auto *coroFrameAllocFn = IGF.IGM.getOpaquePtr(coroAllocPtr);
       auto *nullSwiftCoroFrameAlloc = IGF.Builder.CreateCmp(
         llvm::CmpInst::Predicate::ICMP_NE, coroFrameAllocFn,

lib/IRGen/IRGenModule.cpp

@@ -902,6 +902,14 @@ namespace RuntimeConstants {
     return RuntimeAvailability::AlwaysAvailable;
   }
 
+  RuntimeAvailability TypedCoroAllocAvailability(ASTContext &context) {
+    auto featureAvailability = context.getTypedCoroAllocAvailability();
+    if (!isDeploymentAvailabilityContainedIn(context, featureAvailability)) {
+      return RuntimeAvailability::ConditionallyAvailable;
+    }
+    return RuntimeAvailability::AlwaysAvailable;
+  }
+
   RuntimeAvailability ConcurrencyDiscardingTaskGroupAvailability(ASTContext &context) {
     auto featureAvailability =
         context.getConcurrencyDiscardingTaskGroupAvailability();

test/IRGen/yield_once_enable_emit_type_malloc_coro_frame.sil

@@ -1,5 +1,5 @@
-// REQUIRES: OS=macosx || OS=iOS
-// RUN: %target-swift-frontend -emit-irgen %s | %FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-%target-ptrsize --check-prefix=CHECK-%target-ptrsize-%target-ptrauth
+// REQUIRES: OS=macosx
+// RUN: %target-swift-frontend -target %target-cpu-apple-macosx15.0 -emit-irgen %s | %FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-%target-ptrsize --check-prefix=CHECK-%target-ptrsize-%target-ptrauth
 
 import Builtin
 
@@ -44,6 +44,9 @@ unwind:
   // CHECK-NEXT:    unreachable
 }
 
+// CHECK-32:       declare extern_weak ptr @swift_coroFrameAlloc(i32, i64)
+// CHECK-64:       declare extern_weak ptr @swift_coroFrameAlloc(i64, i64)
+
 // CHECK-32:       define linkonce_odr hidden ptr @__swift_coroFrameAllocStub(i32 %0, i64 %1) #1{{( comdat)?}} {
 // CHECK-64:       define linkonce_odr hidden ptr @__swift_coroFrameAllocStub(i64 %0, i64 %1) #1{{( comdat)?}} {
 // CHECK:       [[T0:%.*]] = icmp ne ptr @swift_coroFrameAlloc, null
@@ -59,9 +62,6 @@ unwind:
 // CHECK-64:         [[T2:%.*]] = call ptr @malloc(i64 %0)
 // CHECK:         ret ptr [[T2]]
 
-// CHECK-32:       declare extern_weak ptr @swift_coroFrameAlloc(i32, i64)
-// CHECK-64:       declare extern_weak ptr @swift_coroFrameAlloc(i64, i64)
-
 // CHECK-LABEL:     declare{{( dllimport)?}}{{( protected)?}} swiftcc void @"$sIetA_TC"
 // CHECK-SAME:      (ptr noalias dereferenceable([[BUFFER_SIZE]]), i1)
 

test/IRGen/yield_once_enable_emit_type_malloc_coro_frame_ios.sil

@@ -0,0 +1,2 @@
+// REQUIRES: OS=iOS
+// RUN: %target-swift-frontend -target %target-cpu-apple-iphoneos16.0 -emit-irgen %S/yield_once_enable_emit_type_malloc_coro_frame.sil | %FileCheck %S/yield_once_enable_emit_type_malloc_coro_frame.sil --check-prefix=CHECK --check-prefix=CHECK-%target-ptrsize --check-prefix=CHECK-%target-ptrsize-%target-ptrauth

test/IRGen/yield_once_enable_emit_type_malloc_coro_frame_macos_new.sil

@@ -0,0 +1,4 @@
+// REQUIRES: OS=macosx
+// RUN: %target-swift-frontend -target %target-cpu-apple-macosx26.0 -emit-irgen %S/yield_once_enable_emit_type_malloc_coro_frame.sil | %FileCheck %s
+
+// CHECK-NOT: __swift_coroFrameAllocStub