r177819 - Make clang to mark static stack allocations with lifetime markers to enable a more aggressive stack coloring.

Alexey Samsonov samsonov at google.com
Mon Mar 25 12:23:51 PDT 2013


Hi Nadav!

Cool you guys are working on it! I have a raw local patch that does the
same (emits llvm.lifetime start/end intrinsics), and
I hope to provide some feedback tomorrow, when I look at this commit in
more details. Some of my concerns:
1) Rafael mentioned a thread where I asked about llvm.lifetime intrinsics
semantics and behavior - you may be
interested in it. I think we may resurrect it and clarify their semantics.
2) I'm afraid that immediate enabling of stack coloring may break things -
I've seen that similar gcc option
had to be disabled on some codebases because of the bugs in the code where
a local variable was used after
it went out of scope.
3) I actually want to emit lifetime.start/end intrinsics in one of
AddressSanitizer modes (to implement -fsanitize=use-after-scope
option) to reliably detect bugs in (2).



On Sat, Mar 23, 2013 at 10:43 AM, Nadav Rotem <nrotem at apple.com> wrote:

> Author: nadav
> Date: Sat Mar 23 01:43:35 2013
> New Revision: 177819
>
> URL: http://llvm.org/viewvc/llvm-project?rev=177819&view=rev
> Log:
> Make clang to mark static stack allocations with lifetime markers to
> enable a more aggressive stack coloring.
> Patch by John McCall with help by Shuxin Yang.
> rdar://13115369
>
>
> Added:
>     cfe/trunk/test/CodeGen/lifetime2.c
> Modified:
>     cfe/trunk/lib/CodeGen/CGDecl.cpp
>     cfe/trunk/lib/CodeGen/CGStmt.cpp
>     cfe/trunk/lib/CodeGen/CodeGenFunction.cpp
>     cfe/trunk/lib/CodeGen/CodeGenFunction.h
>     cfe/trunk/lib/CodeGen/CodeGenModule.cpp
>     cfe/trunk/lib/CodeGen/CodeGenModule.h
>     cfe/trunk/test/CodeGenObjC/arc-blocks.m
>     cfe/trunk/test/CodeGenObjC/arc.m
>
> Modified: cfe/trunk/lib/CodeGen/CGDecl.cpp
> URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDecl.cpp?rev=177819&r1=177818&r2=177819&view=diff
>
> ==============================================================================
> --- cfe/trunk/lib/CodeGen/CGDecl.cpp (original)
> +++ cfe/trunk/lib/CodeGen/CGDecl.cpp Sat Mar 23 01:43:35 2013
> @@ -452,6 +452,22 @@ namespace {
>        CGF.EmitCall(FnInfo, CleanupFn, ReturnValueSlot(), Args);
>      }
>    };
> +
> +  /// A cleanup to call @llvm.lifetime.end.
> +  class CallLifetimeEnd : public EHScopeStack::Cleanup {
> +    llvm::Value *Addr;
> +    llvm::Value *Size;
> +  public:
> +    CallLifetimeEnd(llvm::Value *addr, llvm::Value *size)
> +      : Addr(addr), Size(size) {}
> +
> +    void Emit(CodeGenFunction &CGF, Flags flags) {
> +      llvm::Value *castAddr = CGF.Builder.CreateBitCast(Addr,
> CGF.Int8PtrTy);
> +      CGF.Builder.CreateCall2(CGF.CGM.getLLVMLifetimeEndFn(),
> +                              Size, castAddr)
> +        ->setDoesNotThrow();
> +    }
> +  };
>  }
>
>  /// EmitAutoVarWithLifetime - Does the setup required for an automatic
> @@ -756,7 +772,6 @@ static bool shouldUseMemSetPlusStoresToI
>    // If a global is all zeros, always use a memset.
>    if (isa<llvm::ConstantAggregateZero>(Init)) return true;
>
> -
>    // If a non-zero global is <= 32 bytes, always use a memcpy.  If it is
> large,
>    // do it if it will require 6 or fewer scalar stores.
>    // TODO: Should budget depends on the size?  Avoiding a large global
> warrants
> @@ -768,6 +783,20 @@ static bool shouldUseMemSetPlusStoresToI
>           canEmitInitWithFewStoresAfterMemset(Init, StoreBudget);
>  }
>
> +/// Should we use the LLVM lifetime intrinsics for the given local
> variable?
> +static bool shouldUseLifetimeMarkers(CodeGenFunction &CGF, const VarDecl
> &D,
> +                                     unsigned Size) {
> +  // For now, only in optimized builds.
> +  if (CGF.CGM.getCodeGenOpts().OptimizationLevel == 0)
> +    return false;
> +
> +  // Limit the size of marked objects to 32 bytes. We don't want to
> increase
> +  // compile time by marking tiny objects.
> +  unsigned SizeThreshold = 32;
> +
> +  return Size > SizeThreshold;
> +}
> +
>
>  /// EmitAutoVarDecl - Emit code and set up an entry in LocalDeclMap for a
>  /// variable declaration with auto, register, or no storage class
> specifier.
> @@ -870,6 +899,20 @@ CodeGenFunction::EmitAutoVarAlloca(const
>
>  getContext().toCharUnitsFromBits(Target.getPointerAlign(0)));
>          Alloc->setAlignment(allocaAlignment.getQuantity());
>          DeclPtr = Alloc;
> +
> +        // Emit a lifetime intrinsic if meaningful.  There's no point
> +        // in doing this if we don't have a valid insertion point (?).
> +        uint64_t size = CGM.getDataLayout().getTypeAllocSize(LTy);
> +        if (HaveInsertPoint() && shouldUseLifetimeMarkers(*this, D,
> size)) {
> +          llvm::Value *sizeV = llvm::ConstantInt::get(Int64Ty, size);
> +
> +          emission.SizeForLifetimeMarkers = sizeV;
> +          llvm::Value *castAddr = Builder.CreateBitCast(Alloc, Int8PtrTy);
> +          Builder.CreateCall2(CGM.getLLVMLifetimeStartFn(), sizeV,
> castAddr)
> +            ->setDoesNotThrow();
> +        } else {
> +          assert(!emission.useLifetimeMarkers());
> +        }
>        }
>      } else {
>        // Targets that don't support recursion emit locals as globals.
> @@ -1215,6 +1258,14 @@ void CodeGenFunction::EmitAutoVarCleanup
>
>    const VarDecl &D = *emission.Variable;
>
> +  // Make sure we call @llvm.lifetime.end.  This needs to happen
> +  // *last*, so the cleanup needs to be pushed *first*.
> +  if (emission.useLifetimeMarkers()) {
> +    EHStack.pushCleanup<CallLifetimeEnd>(NormalCleanup,
> +                                         emission.getAllocatedAddress(),
> +
> emission.getSizeForLifetimeMarkers());
> +  }
> +
>    // Check the type for a cleanup.
>    if (QualType::DestructionKind dtorKind = D.getType().isDestructedType())
>      emitAutoVarTypeCleanup(emission, dtorKind);
> @@ -1485,6 +1536,22 @@ void CodeGenFunction::pushRegularPartial
>                                                    elementType, destroyer);
>  }
>
> +/// Lazily declare the @llvm.lifetime.start intrinsic.
> +llvm::Constant *CodeGenModule::getLLVMLifetimeStartFn() {
> +  if (LifetimeStartFn) return LifetimeStartFn;
> +  LifetimeStartFn = llvm::Intrinsic::getDeclaration(&getModule(),
> +
>  llvm::Intrinsic::lifetime_start);
> +  return LifetimeStartFn;
> +}
> +
> +/// Lazily declare the @llvm.lifetime.end intrinsic.
> +llvm::Constant *CodeGenModule::getLLVMLifetimeEndFn() {
> +  if (LifetimeEndFn) return LifetimeEndFn;
> +  LifetimeEndFn = llvm::Intrinsic::getDeclaration(&getModule(),
> +
>  llvm::Intrinsic::lifetime_end);
> +  return LifetimeEndFn;
> +}
> +
>  namespace {
>    /// A cleanup to perform a release of an object at the end of a
>    /// function.  This is used to balance out the incoming +1 of a
>
> Modified: cfe/trunk/lib/CodeGen/CGStmt.cpp
> URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGStmt.cpp?rev=177819&r1=177818&r2=177819&view=diff
>
> ==============================================================================
> --- cfe/trunk/lib/CodeGen/CGStmt.cpp (original)
> +++ cfe/trunk/lib/CodeGen/CGStmt.cpp Sat Mar 23 01:43:35 2013
> @@ -319,6 +319,12 @@ CodeGenFunction::getJumpDestForLabel(con
>  }
>
>  void CodeGenFunction::EmitLabel(const LabelDecl *D) {
> +  // Add this label to the current lexical scope if we're within any
> +  // normal cleanups.  Jumps "in" to this label --- when permitted by
> +  // the language --- may need to be routed around such cleanups.
> +  if (EHStack.hasNormalCleanups() && CurLexicalScope)
> +    CurLexicalScope->addLabel(D);
> +
>    JumpDest &Dest = LabelMap[D];
>
>    // If we didn't need a forward reference to this label, just go
> @@ -330,16 +336,36 @@ void CodeGenFunction::EmitLabel(const La
>    // it from the branch-fixups list.
>    } else {
>      assert(!Dest.getScopeDepth().isValid() && "already emitted label!");
> -    Dest = JumpDest(Dest.getBlock(),
> -                    EHStack.stable_begin(),
> -                    Dest.getDestIndex());
> -
> +    Dest.setScopeDepth(EHStack.stable_begin());
>      ResolveBranchFixups(Dest.getBlock());
>    }
>
>    EmitBlock(Dest.getBlock());
>  }
>
> +/// Change the cleanup scope of the labels in this lexical scope to
> +/// match the scope of the enclosing context.
> +void CodeGenFunction::LexicalScope::rescopeLabels() {
> +  assert(!Labels.empty());
> +  EHScopeStack::stable_iterator innermostScope
> +    = CGF.EHStack.getInnermostNormalCleanup();
> +
> +  // Change the scope depth of all the labels.
> +  for (SmallVectorImpl<const LabelDecl*>::const_iterator
> +         i = Labels.begin(), e = Labels.end(); i != e; ++i) {
> +    assert(CGF.LabelMap.count(*i));
> +    JumpDest &dest = CGF.LabelMap.find(*i)->second;
> +    assert(dest.getScopeDepth().isValid());
> +    assert(innermostScope.encloses(dest.getScopeDepth()));
> +    dest.setScopeDepth(innermostScope);
> +  }
> +
> +  // Reparent the labels if the new scope also has cleanups.
> +  if (innermostScope != EHScopeStack::stable_end() && ParentScope) {
> +    ParentScope->Labels.append(Labels.begin(), Labels.end());
> +  }
> +}
> +
>
>  void CodeGenFunction::EmitLabelStmt(const LabelStmt &S) {
>    EmitLabel(S.getDecl());
>
> Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.cpp
> URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.cpp?rev=177819&r1=177818&r2=177819&view=diff
>
> ==============================================================================
> --- cfe/trunk/lib/CodeGen/CodeGenFunction.cpp (original)
> +++ cfe/trunk/lib/CodeGen/CodeGenFunction.cpp Sat Mar 23 01:43:35 2013
> @@ -45,7 +45,7 @@ CodeGenFunction::CodeGenFunction(CodeGen
>      IndirectBranch(0), SwitchInsn(0), CaseRangeBlock(0),
> UnreachableBlock(0),
>      CXXABIThisDecl(0), CXXABIThisValue(0), CXXThisValue(0),
>      CXXStructorImplicitParamDecl(0), CXXStructorImplicitParamValue(0),
> -    OutermostConditional(0), TerminateLandingPad(0),
> +    OutermostConditional(0), CurLexicalScope(0), TerminateLandingPad(0),
>      TerminateHandler(0), TrapBB(0) {
>    if (!suppressNewContext)
>      CGM.getCXXABI().getMangleContext().startNewFunction();
>
> Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.h
> URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.h?rev=177819&r1=177818&r2=177819&view=diff
>
> ==============================================================================
> --- cfe/trunk/lib/CodeGen/CodeGenFunction.h (original)
> +++ cfe/trunk/lib/CodeGen/CodeGenFunction.h Sat Mar 23 01:43:35 2013
> @@ -562,6 +562,11 @@ public:
>      EHScopeStack::stable_iterator getScopeDepth() const { return
> ScopeDepth; }
>      unsigned getDestIndex() const { return Index; }
>
> +    // This should be used cautiously.
> +    void setScopeDepth(EHScopeStack::stable_iterator depth) {
> +      ScopeDepth = depth;
> +    }
> +
>    private:
>      llvm::BasicBlock *Block;
>      EHScopeStack::stable_iterator ScopeDepth;
> @@ -853,6 +858,8 @@ public:
>
>    class LexicalScope: protected RunCleanupsScope {
>      SourceRange Range;
> +    SmallVector<const LabelDecl*, 4> Labels;
> +    LexicalScope *ParentScope;
>
>      LexicalScope(const LexicalScope &) LLVM_DELETED_FUNCTION;
>      void operator=(const LexicalScope &) LLVM_DELETED_FUNCTION;
> @@ -860,15 +867,23 @@ public:
>    public:
>      /// \brief Enter a new cleanup scope.
>      explicit LexicalScope(CodeGenFunction &CGF, SourceRange Range)
> -      : RunCleanupsScope(CGF), Range(Range) {
> +      : RunCleanupsScope(CGF), Range(Range),
> ParentScope(CGF.CurLexicalScope) {
> +      CGF.CurLexicalScope = this;
>        if (CGDebugInfo *DI = CGF.getDebugInfo())
>          DI->EmitLexicalBlockStart(CGF.Builder, Range.getBegin());
>      }
>
> +    void addLabel(const LabelDecl *label) {
> +      assert(PerformCleanup && "adding label to dead scope?");
> +      Labels.push_back(label);
> +    }
> +
>      /// \brief Exit this cleanup scope, emitting any accumulated
>      /// cleanups.
>      ~LexicalScope() {
> -      if (PerformCleanup) endLexicalScope();
> +      // If we should perform a cleanup, force them now.  Note that
> +      // this ends the cleanup scope before rescoping any labels.
> +      if (PerformCleanup) ForceCleanup();
>      }
>
>      /// \brief Force the emission of cleanups now, instead of waiting
> @@ -880,9 +895,14 @@ public:
>
>    private:
>      void endLexicalScope() {
> +      CGF.CurLexicalScope = ParentScope;
>        if (CGDebugInfo *DI = CGF.getDebugInfo())
>          DI->EmitLexicalBlockEnd(CGF.Builder, Range.getEnd());
> +      if (!Labels.empty())
> +        rescopeLabels();
>      }
> +
> +    void rescopeLabels();
>    };
>
>
> @@ -1205,6 +1225,8 @@ private:
>    /// temporary should be destroyed conditionally.
>    ConditionalEvaluation *OutermostConditional;
>
> +  /// The current lexical scope.
> +  LexicalScope *CurLexicalScope;
>
>    /// ByrefValueInfoMap - For each __block variable, contains a pair of
> the LLVM
>    /// type as well as the field number that contains the actual data.
> @@ -2001,18 +2023,34 @@ public:
>      /// initializer.
>      bool IsConstantAggregate;
>
> +    /// Non-null if we should use lifetime annotations.
> +    llvm::Value *SizeForLifetimeMarkers;
> +
>      struct Invalid {};
>      AutoVarEmission(Invalid) : Variable(0) {}
>
>      AutoVarEmission(const VarDecl &variable)
>        : Variable(&variable), Address(0), NRVOFlag(0),
> -        IsByRef(false), IsConstantAggregate(false) {}
> +        IsByRef(false), IsConstantAggregate(false),
> +        SizeForLifetimeMarkers(0) {}
>
>      bool wasEmittedAsGlobal() const { return Address == 0; }
>
>    public:
>      static AutoVarEmission invalid() { return AutoVarEmission(Invalid());
> }
>
> +    bool useLifetimeMarkers() const { return SizeForLifetimeMarkers != 0;
> }
> +    llvm::Value *getSizeForLifetimeMarkers() const {
> +      assert(useLifetimeMarkers());
> +      return SizeForLifetimeMarkers;
> +    }
> +
> +    /// Returns the raw, allocated address, which is not necessarily
> +    /// the address of the object itself.
> +    llvm::Value *getAllocatedAddress() const {
> +      return Address;
> +    }
> +
>      /// Returns the address of the object within this declaration.
>      /// Note that this does not chase the forwarding pointer for
>      /// __block decls.
>
> Modified: cfe/trunk/lib/CodeGen/CodeGenModule.cpp
> URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenModule.cpp?rev=177819&r1=177818&r2=177819&view=diff
>
> ==============================================================================
> --- cfe/trunk/lib/CodeGen/CodeGenModule.cpp (original)
> +++ cfe/trunk/lib/CodeGen/CodeGenModule.cpp Sat Mar 23 01:43:35 2013
> @@ -86,6 +86,7 @@ CodeGenModule::CodeGenModule(ASTContext
>      NSConcreteGlobalBlock(0), NSConcreteStackBlock(0),
>      BlockObjectAssign(0), BlockObjectDispose(0),
>      BlockDescriptorType(0), GenericBlockLiteralType(0),
> +    LifetimeStartFn(0), LifetimeEndFn(0),
>      SanitizerBlacklist(CGO.SanitizerBlacklistFile),
>      SanOpts(SanitizerBlacklist.isIn(M) ?
>              SanitizerOptions::Disabled : LangOpts.Sanitize) {
>
> Modified: cfe/trunk/lib/CodeGen/CodeGenModule.h
> URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenModule.h?rev=177819&r1=177818&r2=177819&view=diff
>
> ==============================================================================
> --- cfe/trunk/lib/CodeGen/CodeGenModule.h (original)
> +++ cfe/trunk/lib/CodeGen/CodeGenModule.h Sat Mar 23 01:43:35 2013
> @@ -381,6 +381,12 @@ class CodeGenModule : public CodeGenType
>      int GlobalUniqueCount;
>    } Block;
>
> +  /// void @llvm.lifetime.start(i64 %size, i8* nocapture <ptr>)
> +  llvm::Constant *LifetimeStartFn;
> +
> +  /// void @llvm.lifetime.end(i64 %size, i8* nocapture <ptr>)
> +  llvm::Constant *LifetimeEndFn;
> +
>    GlobalDecl initializedGlobalDecl;
>
>    llvm::BlackList SanitizerBlacklist;
> @@ -757,6 +763,9 @@ public:
>
>    ///@}
>
> +  llvm::Constant *getLLVMLifetimeStartFn();
> +  llvm::Constant *getLLVMLifetimeEndFn();
> +
>    // UpdateCompleteType - Make sure that this type is translated.
>    void UpdateCompletedType(const TagDecl *TD);
>
>
> Added: cfe/trunk/test/CodeGen/lifetime2.c
> URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/lifetime2.c?rev=177819&view=auto
>
> ==============================================================================
> --- cfe/trunk/test/CodeGen/lifetime2.c (added)
> +++ cfe/trunk/test/CodeGen/lifetime2.c Sat Mar 23 01:43:35 2013
> @@ -0,0 +1,17 @@
> +// RUN: %clang -S -emit-llvm -o - -O2 %s | FileCheck %s -check-prefix=O2
> +// RUN: %clang -S -emit-llvm -o - -O0 %s | FileCheck %s -check-prefix=O0
> +
> +extern int bar(char *A, int n);
> +
> +// O0-NOT: @llvm.lifetime.start
> +int foo (int n) {
> +  if (n) {
> +// O2: @llvm.lifetime.start
> +    char A[100];
> +    return bar(A, 1);
> +  } else {
> +// O2: @llvm.lifetime.start
> +    char A[100];
> +    return bar(A, 2);
> +  }
> +}
>
> Modified: cfe/trunk/test/CodeGenObjC/arc-blocks.m
> URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenObjC/arc-blocks.m?rev=177819&r1=177818&r2=177819&view=diff
>
> ==============================================================================
> --- cfe/trunk/test/CodeGenObjC/arc-blocks.m (original)
> +++ cfe/trunk/test/CodeGenObjC/arc-blocks.m Sat Mar 23 01:43:35 2013
> @@ -128,7 +128,7 @@ void test4(void) {
>    // CHECK-NEXT: call void @_Block_object_dispose(i8* [[T0]], i32 8)
>    // CHECK-NEXT: [[T0:%.*]] = load i8** [[SLOT]]
>    // CHECK-NEXT: call void @objc_release(i8* [[T0]])
> -  // CHECK-NEXT: ret void
> +  // CHECK: ret void
>
>    // CHECK:    define internal void @__Block_byref_object_copy_
>    // CHECK:      [[T0:%.*]] = getelementptr inbounds [[BYREF_T]]*
> {{%.*}}, i32 0, i32 6
> @@ -207,7 +207,7 @@ void test6(void) {
>    // CHECK:      [[T0:%.*]] = bitcast [[BYREF_T]]* [[VAR]] to i8*
>    // CHECK-NEXT: call void @_Block_object_dispose(i8* [[T0]], i32 8)
>    // CHECK-NEXT: call void @objc_destroyWeak(i8** [[SLOT]])
> -  // CHECK-NEXT: ret void
> +  // CHECK: ret void
>
>    // CHECK:    define internal void @__Block_byref_object_copy_
>    // CHECK:      [[T0:%.*]] = getelementptr inbounds [[BYREF_T]]*
> {{%.*}}, i32 0, i32 6
> @@ -256,14 +256,14 @@ void test7(void) {
>    // CHECK:      call void @test7_helper(
>    // CHECK-NEXT: call void @objc_destroyWeak(i8** {{%.*}})
>    // CHECK-NEXT: call void @objc_destroyWeak(i8** [[VAR]])
> -  // CHECK-NEXT: ret void
> +  // CHECK: ret void
>
>    // CHECK:    define internal void @__test7_block_invoke
>    // CHECK:      [[SLOT:%.*]] = getelementptr inbounds [[BLOCK_T]]*
> {{%.*}}, i32 0, i32 5
>    // CHECK-NEXT: [[T0:%.*]] = call i8* @objc_loadWeakRetained(i8**
> [[SLOT]])
>    // CHECK-NEXT: call void @test7_consume(i8* [[T0]])
>    // CHECK-NEXT: call void @objc_release(i8* [[T0]])
> -  // CHECK-NEXT: ret void
> +  // CHECK: ret void
>
>    // CHECK:    define internal void @__copy_helper_block_
>    // CHECK:      getelementptr
> @@ -296,7 +296,7 @@ void test7(void) {
>  // CHECK-NEXT: [[T1:%.*]] = load [[TEST8]]** [[D0]]
>  // CHECK-NEXT: [[T2:%.*]] = bitcast [[TEST8]]* [[T1]] to i8*
>  // CHECK-NEXT: call void @objc_release(i8* [[T2]])
> -// CHECK-NEXT: ret void
> +// CHECK: ret void
>
>    extern void test8_helper(void (^)(void));
>    test8_helper(^{ (void) self; });
> @@ -354,7 +354,7 @@ void test10a(void) {
>    // CHECK-NEXT: [[T1:%.*]] = load void ()** [[SLOT]]
>    // CHECK-NEXT: [[T2:%.*]] = bitcast void ()* [[T1]] to i8*
>    // CHECK-NEXT: call void @objc_release(i8* [[T2]])
> -  // CHECK-NEXT: ret void
> +  // CHECK: ret void
>  }
>
>  // <rdar://problem/10402698>: do this copy and dispose with
> @@ -374,7 +374,7 @@ void test10a(void) {
>  // CHECK-NEXT: [[T2:%.*]] = call i8* @objc_retainBlock(i8* [[T1]])
>  // CHECK-NEXT: [[T3:%.*]] = bitcast i8* [[T2]] to void ()*
>  // CHECK-NEXT: store void ()* [[T3]], void ()** [[D2]], align 8
> -// CHECK-NEXT: ret void
> +// CHECK: ret void
>
>  // CHECK: define internal void @__Block_byref_object_dispose
>  // CHECK:      [[T0:%.*]] = load i8** {{%.*}}
> @@ -418,7 +418,7 @@ void test10b(void) {
>    // CHECK-NEXT: [[T1:%.*]] = load void ()** [[SLOT]]
>    // CHECK-NEXT: [[T2:%.*]] = bitcast void ()* [[T1]] to i8*
>    // CHECK-NEXT: call void @objc_release(i8* [[T2]])
> -  // CHECK-NEXT: ret void
> +  // CHECK: ret void
>  }
>
>  // rdar://problem/10088932
> @@ -438,7 +438,7 @@ void test11a(void) {
>    // CHECK-NEXT: call void @test11_helper(i8* [[T4]])
>    // CHECK-NEXT: [[T5:%.*]] = bitcast void ()* [[T3]] to i8*
>    // CHECK-NEXT: call void @objc_release(i8* [[T5]])
> -  // CHECK-NEXT: ret void
> +  // CHECK: ret void
>  }
>  void test11b(void) {
>    int x;
> @@ -456,7 +456,7 @@ void test11b(void) {
>    // CHECK-NEXT: store i8* [[T4]], i8** [[B]], align 8
>    // CHECK-NEXT: [[T5:%.*]] = load i8** [[B]]
>    // CHECK-NEXT: call void @objc_release(i8* [[T5]])
> -  // CHECK-NEXT: ret void
> +  // CHECK: ret void
>  }
>
>  // rdar://problem/9979150
>
> Modified: cfe/trunk/test/CodeGenObjC/arc.m
> URL:
> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenObjC/arc.m?rev=177819&r1=177818&r2=177819&view=diff
>
> ==============================================================================
> --- cfe/trunk/test/CodeGenObjC/arc.m (original)
> +++ cfe/trunk/test/CodeGenObjC/arc.m Sat Mar 23 01:43:35 2013
> @@ -353,7 +353,7 @@ void test12(void) {
>    // CHECK-NEXT: [[T4:%.*]] = load i8** [[Y]]
>    // CHECK-NEXT: call void @objc_release(i8* [[T4]]) [[NUW]],
> !clang.imprecise_release
>    // CHECK-NEXT: call void @objc_destroyWeak(i8** [[X]])
> -  // CHECK-NEXT: ret void
> +  // CHECK: ret void
>  }
>
>  // Indirect consuming calls.
> @@ -460,8 +460,9 @@ void test13(void) {
>  void test19() {
>    // CHECK: define void @test19()
>    // CHECK:      [[X:%.*]] = alloca [5 x i8*], align 16
> +  // CHECK: call void @llvm.lifetime.start
>    // CHECK-NEXT: [[T0:%.*]] = bitcast [5 x i8*]* [[X]] to i8*
> -  // CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* [[T0]], i8 0, i64
> 40, i32 16, i1 false)
> +  // CHECK: call void @llvm.memset.p0i8.i64(i8* [[T0]], i8 0, i64 40, i32
> 16, i1 false)
>    id x[5];
>
>    extern id test19_helper(void);
>
>
> _______________________________________________
> cfe-commits mailing list
> cfe-commits at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
>



-- 
Alexey Samsonov, MSK
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