Revert "[ObjCARC][Contract] Optimize bundled RetainRV to ClaimRV (#139762)"

This reverts commit 810148c.

Author: citymarina

llvm/lib/Transforms/ObjCARC/ARCRuntimeEntryPoints.h

@@ -42,7 +42,6 @@ enum class ARCRuntimeEntryPointKind {
   Autorelease,
   StoreStrong,
   RetainRV,
-  ClaimRV,
   UnsafeClaimRV,
   RetainAutorelease,
   RetainAutoreleaseRV,
@@ -63,7 +62,6 @@ class ARCRuntimeEntryPoints {
     Autorelease = nullptr;
     StoreStrong = nullptr;
     RetainRV = nullptr;
-    ClaimRV = nullptr;
     UnsafeClaimRV = nullptr;
     RetainAutorelease = nullptr;
     RetainAutoreleaseRV = nullptr;
@@ -89,9 +87,6 @@ class ARCRuntimeEntryPoints {
     case ARCRuntimeEntryPointKind::RetainRV:
       return getIntrinsicEntryPoint(RetainRV,
                                 Intrinsic::objc_retainAutoreleasedReturnValue);
-    case ARCRuntimeEntryPointKind::ClaimRV:
-      return getIntrinsicEntryPoint(
-          ClaimRV, Intrinsic::objc_claimAutoreleasedReturnValue);
     case ARCRuntimeEntryPointKind::UnsafeClaimRV:
       return getIntrinsicEntryPoint(
           UnsafeClaimRV, Intrinsic::objc_unsafeClaimAutoreleasedReturnValue);
@@ -131,9 +126,6 @@ class ARCRuntimeEntryPoints {
   /// Declaration for objc_retainAutoreleasedReturnValue().
   Function *RetainRV = nullptr;
 
-  /// Declaration for objc_claimAutoreleasedReturnValue().
-  Function *ClaimRV = nullptr;
-
   /// Declaration for objc_unsafeClaimAutoreleasedReturnValue().
   Function *UnsafeClaimRV = nullptr;
 

llvm/lib/Transforms/ObjCARC/ObjCARC.cpp

@@ -101,37 +101,8 @@ BundledRetainClaimRVs::~BundledRetainClaimRVs() {
       // can't be tail calls.
       if (auto *CI = dyn_cast<CallInst>(CB))
         CI->setTailCallKind(CallInst::TCK_NoTail);
-
-      // We can also do one final optimization: modify the bundle in the
-      // annotated call, to change the bundle operand from
-      //   objc_retainAutoreleasedReturnValue
-      // to:
-      //   objc_claimAutoreleasedReturnValue
-      // allowing the marker to be omitted from the bundle expansion later.
-      //
-      // Note that, confusingly, ClaimRV is semantically equivalent to RetainRV,
-      // and only differs in that it doesn't require the marker.
-      // The bundle provides the guarantee that we're emitting the ClaimRV call
-      // adjacent to the original call, and providing that guarantee is the
-      // only difference between ClaimRV and RetainRV.
-      //
-      // UnsafeClaimRV has a different RC contract entirely.
-
-      // Find the clang.arc.attachedcall bundle, and rewrite its operand.
-      if (UseClaimRV) {
-        for (auto OBI : CB->bundle_op_infos()) {
-          auto OBU = CB->operandBundleFromBundleOpInfo(OBI);
-          if (OBU.getTagID() == LLVMContext::OB_clang_arc_attachedcall &&
-              OBU.Inputs[0] == EP.get(ARCRuntimeEntryPointKind::RetainRV)) {
-            CB->setOperand(OBI.Begin,
-                           EP.get(ARCRuntimeEntryPointKind::ClaimRV));
-            break;
-          }
-        }
-      }
     }
 
-    // Erase the RV call we emitted earlier: it's already in the bundle.
     EraseInstruction(P.first);
   }
 

llvm/lib/Transforms/ObjCARC/ObjCARC.h

@@ -22,7 +22,6 @@
 #ifndef LLVM_LIB_TRANSFORMS_OBJCARC_OBJCARC_H
 #define LLVM_LIB_TRANSFORMS_OBJCARC_OBJCARC_H
 
-#include "ARCRuntimeEntryPoints.h"
 #include "llvm/Analysis/ObjCARCAnalysisUtils.h"
 #include "llvm/Analysis/ObjCARCUtil.h"
 #include "llvm/IR/EHPersonalities.h"
@@ -105,9 +104,7 @@ CallInst *createCallInstWithColors(
 
 class BundledRetainClaimRVs {
 public:
-  BundledRetainClaimRVs(ARCRuntimeEntryPoints &EP, bool ContractPass,
-                        bool UseClaimRV)
-      : EP(EP), ContractPass(ContractPass), UseClaimRV(UseClaimRV) {}
+  BundledRetainClaimRVs(bool ContractPass) : ContractPass(ContractPass) {}
   ~BundledRetainClaimRVs();
 
   /// Insert a retainRV/claimRV call to the normal destination blocks of invokes
@@ -158,9 +155,7 @@ class BundledRetainClaimRVs {
   /// A map of inserted retainRV/claimRV calls to annotated calls/invokes.
   DenseMap<CallInst *, CallBase *> RVCalls;
 
-  ARCRuntimeEntryPoints &EP;
   bool ContractPass;
-  bool UseClaimRV;
 };
 
 } // end namespace objcarc

llvm/lib/Transforms/ObjCARC/ObjCARCContract.cpp

@@ -42,7 +42,6 @@
 #include "llvm/InitializePasses.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/TargetParser/Triple.h"
 #include "llvm/Transforms/ObjCARC.h"
 
 using namespace llvm;
@@ -53,11 +52,6 @@ using namespace llvm::objcarc;
 STATISTIC(NumPeeps,       "Number of calls peephole-optimized");
 STATISTIC(NumStoreStrongs, "Number objc_storeStrong calls formed");
 
-static cl::opt<cl::boolOrDefault> UseObjCClaimRV(
-    "arc-contract-use-objc-claim-rv",
-    cl::desc(
-        "Enable generation of calls to objc_claimAutoreleasedReturnValue"));
-
 //===----------------------------------------------------------------------===//
 //                                Declarations
 //===----------------------------------------------------------------------===//
@@ -80,9 +74,6 @@ class ObjCARCContract {
   /// A flag indicating whether this optimization pass should run.
   bool Run;
 
-  /// Whether objc_claimAutoreleasedReturnValue is available.
-  bool HasClaimRV = false;
-
   /// The inline asm string to insert between calls and RetainRV calls to make
   /// the optimization work on targets which need it.
   const MDString *RVInstMarker;
@@ -526,39 +517,6 @@ bool ObjCARCContract::tryToPeepholeInstruction(
   }
 }
 
-/// Should we use objc_claimAutoreleasedReturnValue?
-static bool useClaimRuntimeCall(Module &M) {
-  // Let the flag override our OS-based default.
-  if (UseObjCClaimRV != cl::BOU_UNSET)
-    return UseObjCClaimRV == cl::BOU_TRUE;
-
-  Triple TT(M.getTargetTriple());
-
-  // On x86_64, claimARV doesn't make sense, as the marker isn't actually a nop
-  // there (it's needed by the calling convention).
-  if (!TT.isAArch64())
-    return false;
-
-  unsigned Major = TT.getOSMajorVersion();
-  switch (TT.getOS()) {
-  default:
-    return false;
-  case Triple::IOS:
-  case Triple::TvOS:
-    return Major >= 16;
-  case Triple::WatchOS:
-    return Major >= 9;
-  case Triple::BridgeOS:
-    return Major >= 7;
-  case Triple::MacOSX:
-    return Major >= 13;
-  case Triple::Darwin:
-    return Major >= 21;
-  }
-
-  return false;
-}
-
 //===----------------------------------------------------------------------===//
 //                              Top Level Driver
 //===----------------------------------------------------------------------===//
@@ -570,8 +528,6 @@ bool ObjCARCContract::init(Module &M) {
 
   EP.init(&M);
 
-  HasClaimRV = useClaimRuntimeCall(M);
-
   // Initialize RVInstMarker.
   RVInstMarker = getRVInstMarker(M);
 
@@ -589,7 +545,7 @@ bool ObjCARCContract::run(Function &F, AAResults *A, DominatorTree *D) {
   AA = A;
   DT = D;
   PA.setAA(A);
-  BundledRetainClaimRVs BRV(EP, /*ContractPass=*/true, HasClaimRV);
+  BundledRetainClaimRVs BRV(/*ContractPass=*/true);
   BundledInsts = &BRV;
 
   std::pair<bool, bool> R = BundledInsts->insertAfterInvokes(F, DT);

llvm/lib/Transforms/ObjCARC/ObjCARCOpts.cpp

@@ -2423,7 +2423,7 @@ bool ObjCARCOpt::run(Function &F, AAResults &AA) {
     return false;
 
   Changed = CFGChanged = false;
-  BundledRetainClaimRVs BRV(EP, /*ContractPass=*/false, /*UseClaimRV=*/false);
+  BundledRetainClaimRVs BRV(/*ContractPass=*/false);
   BundledInsts = &BRV;
 
   LLVM_DEBUG(dbgs() << "<<< ObjCARCOpt: Visiting Function: " << F.getName()