Revert "Implement bridgeobject_retain/release merging in LLVMARCContract. rdar://22108790"

This reverts commit r32132.  It broke tests:

Swift :: 1_stdlib/FloatingPoint.swift.gyb
Swift :: 1_stdlib/NSStringAPI.swift
Swift :: 1_stdlib/Runtime.swift
Swift :: Interpreter/SDK/CoreGraphics_CGFloat.swift

Swift SVN r32142

lib/LLVMPasses/ARCEntryPointBuilder.h

@@ -47,12 +47,9 @@ class ARCEntryPointBuilder {
   NullablePtr<Constant> ReleaseN;
   NullablePtr<Constant> UnknownRetainN;
   NullablePtr<Constant> UnknownReleaseN;
-  NullablePtr<Constant> BridgeRetainN;
-  NullablePtr<Constant> BridgeReleaseN;
 
   // The type cache.
   NullablePtr<Type> ObjectPtrTy;
-  NullablePtr<Type> BridgeObjectPtrTy;
 
 public:
   ARCEntryPointBuilder(Function &F) : B(F.begin()), Retain(), ObjectPtrTy() {}
@@ -141,21 +138,6 @@ public:
     return CI;
   }
 
-  CallInst *createBridgeRetainN(Value *V, uint32_t n) {
-    // Cast just to make sure we have the right object type.
-    V = B.CreatePointerCast(V, getBridgeObjectPtrTy());
-    CallInst *CI = B.CreateCall(getBridgeRetainN(), {V, getIntConstant(n)});
-    CI->setTailCall(true);
-    return CI;
-  }
-
-  CallInst *createBridgeReleaseN(Value *V, uint32_t n) {
-    // Cast just to make sure we have the right object type.
-    V = B.CreatePointerCast(V, getBridgeObjectPtrTy());
-    CallInst *CI = B.CreateCall(getBridgeReleaseN(), {V, getIntConstant(n)});
-    CI->setTailCall(true);
-    return CI;
-  }
 
 private:
   Module &getModule() {
@@ -271,40 +253,6 @@ private:
     return UnknownReleaseN.get();
   }
 
-  /// Return a callable function for swift_bridgeRetain_n.
-  Constant *getBridgeRetainN() {
-    if (BridgeRetainN)
-      return BridgeRetainN.get();
-    auto *BridgeObjectPtrTy = getBridgeObjectPtrTy();
-    auto &M = getModule();
-
-    auto *Int32Ty = Type::getInt32Ty(M.getContext());
-    auto AttrList = AttributeSet::get(
-        M.getContext(), AttributeSet::FunctionIndex, Attribute::NoUnwind);
-    BridgeRetainN = M.getOrInsertFunction("swift_bridgeObjectRetain_n",
-                                          AttrList, BridgeObjectPtrTy,
-                                          BridgeObjectPtrTy,
-                                          Int32Ty, nullptr);
-    return BridgeRetainN.get();
-  }
-
-  /// Return a callable function for swift_bridgeRelease_n.
-  Constant *getBridgeReleaseN() {
-    if (BridgeReleaseN)
-      return BridgeReleaseN.get();
-    auto *ObjectPtrTy = getObjectPtrTy();
-    auto &M = getModule();
-
-    auto *Int32Ty = Type::getInt32Ty(M.getContext());
-    auto AttrList = AttributeSet::get(
-        M.getContext(), AttributeSet::FunctionIndex, Attribute::NoUnwind);
-    BridgeReleaseN = M.getOrInsertFunction("swift_bridgeObjectRelease_n",
-                                            AttrList,
-                                            Type::getVoidTy(M.getContext()),
-                                            BridgeObjectPtrTy, Int32Ty,
-                                            nullptr);
-    return BridgeReleaseN.get();
-  }
 
   Type *getObjectPtrTy() {
     if (ObjectPtrTy)
@@ -315,15 +263,6 @@ private:
     return ObjectPtrTy.get();
   }
 
-  Type *getBridgeObjectPtrTy() {
-    if (BridgeObjectPtrTy)
-      return BridgeObjectPtrTy.get();
-    auto &M = getModule();
-    BridgeObjectPtrTy = M.getTypeByName("swift.bridge")->getPointerTo();
-    assert(BridgeObjectPtrTy && "Could not find the swift bridge object type by name");
-    return BridgeObjectPtrTy.get();
-  }
-
   Constant *getIntConstant(uint32_t constant) {
     auto &M = getModule();
     auto *Int32Ty = Type::getInt32Ty(M.getContext());

lib/LLVMPasses/LLVMARCContract.cpp

@@ -32,9 +32,6 @@ STATISTIC(NumRetainReleasesEliminatedByMergingIntoRetainReleaseN,
 STATISTIC(NumUnknownRetainReleasesEliminatedByMergingIntoRetainReleaseN,
           "Number of retain/release eliminated by merging into "
           "unknownRetain_n/unknownRelease_n");
-STATISTIC(NumBridgeRetainReleasesEliminatedByMergingIntoRetainReleaseN,
-          "Number of bridge retain/release eliminated by merging into "
-          "bridgeRetain_n/bridgeRelease_n");
 
 /// Pimpl implementation of SwiftARCContractPass.
 namespace {
@@ -44,8 +41,6 @@ struct LocalState {
   TinyPtrVector<CallInst *> ReleaseList;
   TinyPtrVector<CallInst *> UnknownRetainList;
   TinyPtrVector<CallInst *> UnknownReleaseList;
-  TinyPtrVector<CallInst *> BridgeRetainList;
-  TinyPtrVector<CallInst *> BridgeReleaseList;
 };
 
 /// This implements the very late (just before code generation) lowering
@@ -170,45 +165,6 @@ performRRNOptimization(DenseMap<Value *, LocalState> &PtrToLocalStateMap) {
     }
     UnknownReleaseList.clear();
 
-    auto &BridgeRetainList = P.second.BridgeRetainList;
-    if (BridgeRetainList.size() > 1) {
-      // Create the releaseN call right by the last release.
-      auto *OldCI = BridgeRetainList[BridgeRetainList.size() - 1];
-      B.setInsertPoint(OldCI);
-      O = OldCI->getArgOperand(0);
-      // Bridge retain may modify the input reference before forwarding it.
-      auto *I = B.createBridgeRetainN(RC->getSwiftRCIdentityRoot(O),
-                                      BridgeRetainList.size());
-
-      // Remove all old retain instructions.
-      for (auto *Inst : BridgeRetainList) {
-        Inst->replaceAllUsesWith(I);
-        Inst->eraseFromParent();
-        NumBridgeRetainReleasesEliminatedByMergingIntoRetainReleaseN++;
-      }
-
-      NumBridgeRetainReleasesEliminatedByMergingIntoRetainReleaseN--;
-    }
-    BridgeRetainList.clear();
-
-    auto &BridgeReleaseList = P.second.BridgeReleaseList;
-    if (BridgeReleaseList.size() > 1) {
-      // Create the releaseN call right by the last release.
-      auto *OldCI = BridgeReleaseList[BridgeReleaseList.size() - 1];
-      B.setInsertPoint(OldCI);
-      O = OldCI->getArgOperand(0);
-      B.createBridgeReleaseN(RC->getSwiftRCIdentityRoot(O),
-                              BridgeReleaseList.size());
-
-      // Remove all old release instructions.
-      for (auto *Inst : BridgeReleaseList) {
-        Inst->eraseFromParent();
-        NumBridgeRetainReleasesEliminatedByMergingIntoRetainReleaseN++;
-      }
-
-      NumBridgeRetainReleasesEliminatedByMergingIntoRetainReleaseN--;
-    }
-    BridgeReleaseList.clear();
   }
 }
 
@@ -272,25 +228,11 @@ bool SwiftARCContractImpl::run() {
         LocalEntry.UnknownReleaseList.push_back(CI);
         continue;
       }
-      case RT_BridgeRetain: {
-        auto *CI = cast<CallInst>(&Inst);
-        auto *ArgVal = RC->getSwiftRCIdentityRoot(CI->getArgOperand(0));
-
-        LocalState &LocalEntry = PtrToLocalStateMap[ArgVal];
-        LocalEntry.BridgeRetainList.push_back(CI);
-        continue;
-      }
-      case RT_BridgeRelease: {
-        auto *CI = cast<CallInst>(&Inst);
-        auto *ArgVal = RC->getSwiftRCIdentityRoot(CI->getArgOperand(0));
-
-        LocalState &LocalEntry = PtrToLocalStateMap[ArgVal];
-        LocalEntry.BridgeReleaseList.push_back(CI);
-        continue;
-      }
       case RT_Unknown:
       case RT_AllocObject:
       case RT_NoMemoryAccessed:
+      case RT_BridgeRelease:
+      case RT_BridgeRetain:
       case RT_RetainUnowned:
       case RT_CheckUnowned:
       case RT_ObjCRelease:

test/LLVMPasses/contract.ll

@@ -5,11 +5,8 @@ target triple = "x86_64-apple-macosx10.9"
 
 %swift.refcounted = type { %swift.heapmetadata*, i64 }
 %swift.heapmetadata = type { i64 (%swift.refcounted*)*, i64 (%swift.refcounted*)* }
-%swift.bridge = type opaque
 
 declare %swift.refcounted* @swift_allocObject(%swift.heapmetadata* , i64, i64) nounwind
-declare %swift.bridge* @swift_bridgeObjectRetain(%swift.bridge*)
-declare void @swift_bridgeObjectRelease(%swift.bridge* )
 declare void @swift_release(%swift.refcounted* nocapture)
 declare void @swift_retain(%swift.refcounted* ) nounwind
 declare void @swift_unknownRelease(%swift.refcounted* nocapture)
@@ -17,8 +14,6 @@ declare void @swift_unknownRetain(%swift.refcounted* ) nounwind
 declare void @swift_fixLifetime(%swift.refcounted*)
 declare void @noread_user(%swift.refcounted*) readnone
 declare void @user(%swift.refcounted*)
-declare void @noread_user_bridged(%swift.bridge*) readnone
-declare void @user_bridged(%swift.bridge*)
 
 ; CHECK-LABEL: define void @fixlifetime_removal(i8*) {
 ; CHECK-NOT: call void swift_fixLifetime
@@ -501,77 +496,6 @@ bb3:
   ret %swift.refcounted* %A
 }
 
-
-; CHECK-LABEL: define %swift.bridge* @swift_contractBridgeRetainWithBridge(%swift.bridge* %A) {
-; CHECK: bb1:
-; CHECK-NEXT: [[RET0:%.+]] = tail call %swift.bridge* @swift_bridgeObjectRetain_n(%swift.bridge* %A, i32 2)
-; CHECK-NEXT: tail call void @swift_bridgeObjectRelease(%swift.bridge* [[RET0:%.+]])
-; CHECK-NEXT: tail call void @swift_bridgeObjectRelease(%swift.bridge* %A)
-; CHECK-NEXT: ret %swift.bridge* %A
-define %swift.bridge* @swift_contractBridgeRetainWithBridge(%swift.bridge* %A) {
-bb1:
-  %0 = tail call %swift.bridge* @swift_bridgeObjectRetain(%swift.bridge* %A)
-  %1 = tail call %swift.bridge* @swift_bridgeObjectRetain(%swift.bridge* %A)
-  tail call void @swift_bridgeObjectRelease(%swift.bridge* %1)
-  tail call void @swift_bridgeObjectRelease(%swift.bridge* %A)
-  ret %swift.bridge* %A
-}
-
-; CHECK-LABEL: define %swift.bridge* @swift_contractBridgeRetainReleaseNInterleavedWithBridge(%swift.bridge* %A) {
-; CHECK: bb1:
-; CHECK-NEXT: [[RET0:%.+]] = tail call %swift.bridge* @swift_bridgeObjectRetain(%swift.bridge* %A)
-; CHECK-NEXT: call void @user_bridged(%swift.bridge* %A)
-; CHECK-NEXT: call void @noread_user_bridged(%swift.bridge* %A)
-; CHECK-NEXT: tail call void @swift_bridgeObjectRelease_n(%swift.bridge* %A, i32 2)
-; CHECK-NEXT: call void @user_bridged(%swift.bridge* %A)
-; CHECK-NEXT: [[RET1:%.+]] = tail call %swift.bridge* @swift_bridgeObjectRetain_n(%swift.bridge* %A, i32 2)
-; CHECK-NEXT: tail call void @swift_bridgeObjectRelease(%swift.bridge* %A)
-; CHECK-NEXT: call void @user_bridged(%swift.bridge* %A)
-; CHECK-NEXT: call void @noread_user_bridged(%swift.bridge* %A)
-; CHECK-NEXT: tail call void @swift_bridgeObjectRelease_n(%swift.bridge* %A, i32 2)
-; CHECK-NEXT: call void @user_bridged(%swift.bridge* %A)
-; CHECK-NEXT: br label %bb3
-; CHECK: bb2:
-; CHECK-NEXT: call void @user_bridged(%swift.bridge* %A)
-; CHECK-NEXT: call void @swift_bridgeObjectRelease(%swift.bridge* %A)
-; CHECK-NEXT: call void @user_bridged(%swift.bridge* %A)
-; CHECK-NEXT: br label %bb3
-
-; CHECK: bb3:
-; CHECK-NEXT: tail call void @swift_bridgeObjectRelease(%swift.bridge* %A)
-; CHECK-NEXT: ret %swift.bridge* %A
-define %swift.bridge* @swift_contractBridgeRetainReleaseNInterleavedWithBridge(%swift.bridge* %A) {
-entry:
-  br i1 undef, label %bb1, label %bb2
-
-bb1:
-  tail call %swift.bridge* @swift_bridgeObjectRetain(%swift.bridge* %A)
-  call void @user_bridged(%swift.bridge* %A)
-  tail call void @swift_bridgeObjectRelease(%swift.bridge* %A)
-  call void @noread_user_bridged(%swift.bridge* %A)
-  tail call void @swift_bridgeObjectRelease(%swift.bridge* %A)
-  call void @user_bridged(%swift.bridge* %A)
-  tail call %swift.bridge* @swift_bridgeObjectRetain(%swift.bridge* %A)
-  tail call %swift.bridge* @swift_bridgeObjectRetain(%swift.bridge* %A)
-  tail call void @swift_bridgeObjectRelease(%swift.bridge* %A)
-  call void @user_bridged(%swift.bridge* %A)
-  tail call void @swift_bridgeObjectRelease(%swift.bridge* %A)
-  call void @noread_user_bridged(%swift.bridge* %A)
-  tail call void @swift_bridgeObjectRelease(%swift.bridge* %A)
-  call void @user_bridged(%swift.bridge* %A)
-  br label %bb3
-
-bb2:
-  call void @user_bridged(%swift.bridge* %A)
-  tail call void @swift_bridgeObjectRelease(%swift.bridge* %A)
-  call void @user_bridged(%swift.bridge* %A)
-  br label %bb3
-
-bb3:
-  tail call void @swift_bridgeObjectRelease(%swift.bridge* %A)
-  ret %swift.bridge* %A
-}
-
 !llvm.dbg.cu = !{!1}
 !llvm.module.flags = !{!4}