[cfe-commits] r128274 - in /cfe/trunk/lib/CodeGen: CGObjCGNU.cpp CGObjCMac.cpp CGObjCRuntime.cpp CGObjCRuntime.h

David Chisnall csdavec at swan.ac.uk
Fri Mar 25 04:57:33 PDT 2011


Author: theraven
Date: Fri Mar 25 06:57:33 2011
New Revision: 128274

URL: http://llvm.org/viewvc/llvm-project?rev=128274&view=rev
Log:
Continuing work on ObjC tidyup:

- Moved the CGObjCRuntime functions out of CGObjCMac.cpp into CGObjCRuntime.cpp

- Added generic functions in CGObjCRuntime for emitting @try and @synchronize
  blocks, usable by any runtime that uses DWARF exceptions.

- Made the GNU runtimes use these functions.

It should now be possible to replace the equivalent functions in
CGObjCNonFragileABIMac with simple calls to these two functions, providing the
runtime functions as arguments.  I'll post a diff to the list for review before
making any changes to the Mac runtime stuff.


Added:
    cfe/trunk/lib/CodeGen/CGObjCRuntime.cpp
Modified:
    cfe/trunk/lib/CodeGen/CGObjCGNU.cpp
    cfe/trunk/lib/CodeGen/CGObjCMac.cpp
    cfe/trunk/lib/CodeGen/CGObjCRuntime.h

Modified: cfe/trunk/lib/CodeGen/CGObjCGNU.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGObjCGNU.cpp?rev=128274&r1=128273&r2=128274&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGObjCGNU.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGObjCGNU.cpp Fri Mar 25 06:57:33 2011
@@ -74,6 +74,7 @@
        CGM =Mod;
        FunctionName = name;
        Function = 0;
+       ArgTys.clear();
        va_list Args;
        va_start(Args, RetTy);
          while (const llvm::Type *ArgTy = va_arg(Args, const llvm::Type*))
@@ -88,12 +89,15 @@
     */
    operator llvm::Function*() {
      if (!Function) {
-       assert(0 != CGM && "Using an uninitialized LazyRuntimeFunction!");
+       if (0 == FunctionName) return 0;
+       // We put the return type on the end of the vector, so pop it back off
        const llvm::Type *RetTy = ArgTys.back();
        ArgTys.pop_back();
        llvm::FunctionType *FTy = llvm::FunctionType::get(RetTy, ArgTys, false);
        Function =
          cast<llvm::Function>(CGM->CreateRuntimeFunction(FTy, FunctionName));
+       // We won't need to use the types again, so we may as well clean up the
+       // vector now
        ArgTys.resize(0);
      }
      return Function;
@@ -128,26 +132,64 @@
   const llvm::Type *BoolTy;
   /// Metadata kind used to tie method lookups to message sends.
   unsigned msgSendMDKind;
-  llvm::Constant *MakeConstantString(const std::string &Str, const std::string
+  llvm::Constant *MakeConstantString(const std::string &Str,
+                                     const std::string &Name="") {
+    llvm::Constant *ConstStr = CGM.GetAddrOfConstantCString(Str, Name.c_str());
+    return llvm::ConstantExpr::getGetElementPtr(ConstStr, Zeros, 2);
+  }
+  llvm::Constant *ExportUniqueString(const std::string &Str,
+                                     const std::string prefix) {
+    std::string name = prefix + Str;
+    llvm::Constant *ConstStr = TheModule.getGlobalVariable(name);
+    if (!ConstStr) {
+      llvm::Constant *value = llvm::ConstantArray::get(VMContext, Str, true);
+      ConstStr = new llvm::GlobalVariable(TheModule, value->getType(), true,
+              llvm::GlobalValue::LinkOnceODRLinkage, value, prefix + Str);
+    }
+    return llvm::ConstantExpr::getGetElementPtr(ConstStr, Zeros, 2);
+  }
 
-      &Name="");
-  llvm::Constant *ExportUniqueString(const std::string &Str, const std::string
-          prefix);
   llvm::GlobalVariable *MakeGlobal(const llvm::StructType *Ty,
-    std::vector<llvm::Constant*> &V, llvm::StringRef Name="",
-    llvm::GlobalValue::LinkageTypes linkage=llvm::GlobalValue::InternalLinkage);
+                                   std::vector<llvm::Constant*> &V,
+                                   llvm::StringRef Name="",
+                                   llvm::GlobalValue::LinkageTypes linkage
+                                         =llvm::GlobalValue::InternalLinkage) {
+    llvm::Constant *C = llvm::ConstantStruct::get(Ty, V);
+    return new llvm::GlobalVariable(TheModule, Ty, false,
+        linkage, C, Name);
+  }
+
   llvm::GlobalVariable *MakeGlobal(const llvm::ArrayType *Ty,
-    std::vector<llvm::Constant*> &V, llvm::StringRef Name="",
-    llvm::GlobalValue::LinkageTypes linkage=llvm::GlobalValue::InternalLinkage);
+                                   std::vector<llvm::Constant*> &V,
+                                   llvm::StringRef Name="",
+                                   llvm::GlobalValue::LinkageTypes linkage
+                                         =llvm::GlobalValue::InternalLinkage) {
+    llvm::Constant *C = llvm::ConstantArray::get(Ty, V);
+    return new llvm::GlobalVariable(TheModule, Ty, false,
+                                    linkage, C, Name);
+  }
   llvm::GlobalVariable *MakeGlobalArray(const llvm::Type *Ty,
-    std::vector<llvm::Constant*> &V, llvm::StringRef Name="",
-    llvm::GlobalValue::LinkageTypes linkage=llvm::GlobalValue::InternalLinkage);
+                                        std::vector<llvm::Constant*> &V,
+                                        llvm::StringRef Name="",
+                                        llvm::GlobalValue::LinkageTypes linkage
+                                         =llvm::GlobalValue::InternalLinkage) {
+    llvm::ArrayType *ArrayTy = llvm::ArrayType::get(Ty, V.size());
+    return MakeGlobal(ArrayTy, V, Name, linkage);
+  }
+  /**
+   * Ensures that the value has the required type, by inserting a bitcast if
+   * required.  This function lets us avoid inserting bitcasts that are
+   * redundant.
+   */
   llvm::Value* EnforceType(CGBuilderTy B, llvm::Value *V, const llvm::Type *Ty){
     if (V->getType() == Ty) return V;
     return B.CreateBitCast(V, Ty);
   }
   // Some zeros used for GEPs in lots of places.
   llvm::Constant *Zeros[2];
+  /**
+   * Null pointer value.  Mainly used as a terminator in various arrays.
+   */
   llvm::Constant *NULLPtr;
   llvm::LLVMContext &VMContext;
 private:
@@ -180,10 +222,16 @@
   LazyRuntimeFunction IvarAssignFn, StrongCastAssignFn, MemMoveFn, WeakReadFn, 
     WeakAssignFn, GlobalAssignFn;
 
+protected:
   LazyRuntimeFunction ExceptionThrowFn;
+  LazyRuntimeFunction ExceptionReThrowFn;
+  LazyRuntimeFunction EnterCatchFn;
+  LazyRuntimeFunction ExitCatchFn;
   LazyRuntimeFunction SyncEnterFn;
   LazyRuntimeFunction SyncExitFn;
 
+private:
+
   LazyRuntimeFunction EnumerationMutationFn;
   LazyRuntimeFunction GetPropertyFn;
   LazyRuntimeFunction SetPropertyFn;
@@ -237,7 +285,6 @@
   llvm::GlobalVariable *ObjCIvarOffsetVariable(const ObjCInterfaceDecl *ID,
       const ObjCIvarDecl *Ivar);
   void EmitClassRef(const std::string &className);
-  void EmitObjCXXTryStmt(CodeGenFunction &CGF, const ObjCAtTryStmt &S);
 protected:
   virtual llvm::Value *LookupIMP(CodeGenFunction &CGF,
                                  llvm::Value *&Receiver,
@@ -463,6 +510,16 @@
       // Slot_t objc_msg_lookup_super(struct objc_super*, SEL);
       SlotLookupSuperFn.init(&CGM, "objc_slot_lookup_super", SlotTy,
               PtrToObjCSuperTy, SelectorTy, NULL);
+      // If we're in ObjC++ mode, then we want to make 
+      if (CGM.getLangOptions().CPlusPlus) {
+        const llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext);
+        // void *__cxa_begin_catch(void *e)
+        EnterCatchFn.init(&CGM, "__cxa_begin_catch", PtrTy, PtrTy, NULL);
+        // void __cxa_end_catch(void)
+        EnterCatchFn.init(&CGM, "__cxa_end_catch", VoidTy, NULL);
+        // void _Unwind_Resume_or_Rethrow(void*)
+        EnterCatchFn.init(&CGM, "_Unwind_Resume_or_Rethrow", VoidTy, PtrTy, NULL);
+      }
     }
 };
 
@@ -551,6 +608,7 @@
 
   // void objc_exception_throw(id);
   ExceptionThrowFn.init(&CGM, "objc_exception_throw", VoidTy, IdTy, NULL);
+  ExceptionReThrowFn.init(&CGM, "objc_exception_throw", VoidTy, IdTy, NULL);
   // int objc_sync_enter(id);
   SyncEnterFn.init(&CGM, "objc_sync_enter", IntTy, IdTy, NULL);
   // int objc_sync_exit(id);
@@ -580,6 +638,7 @@
   IMPTy = llvm::PointerType::getUnqual(llvm::FunctionType::get(IdTy, IMPArgs,
               true));
 
+  // Don't bother initialising the GC stuff unless we're compiling in GC mode
   if (CGM.getLangOptions().getGCMode() != LangOptions::NonGC) {
     // Get selectors needed in GC mode
     RetainSel = GetNullarySelector("retain", CGM.getContext());
@@ -671,6 +730,29 @@
 }
 
 llvm::Constant *CGObjCGNU::GetEHType(QualType T) {
+  if (!CGM.getLangOptions().CPlusPlus) {
+      if (T->isObjCIdType()
+          || T->isObjCQualifiedIdType()) {
+        // With the old ABI, there was only one kind of catchall, which broke
+        // foreign exceptions.  With the new ABI, we use __objc_id_typeinfo as
+        // a pointer indicating object catchalls, and NULL to indicate real
+        // catchalls
+        if (CGM.getLangOptions().ObjCNonFragileABI) {
+          return MakeConstantString("@id");
+        } else {
+          return 0;
+        }
+      }
+
+      // All other types should be Objective-C interface pointer types.
+      const ObjCObjectPointerType *OPT =
+        T->getAs<ObjCObjectPointerType>();
+      assert(OPT && "Invalid @catch type.");
+      const ObjCInterfaceDecl *IDecl =
+        OPT->getObjectType()->getInterface();
+      assert(IDecl && "Invalid @catch type.");
+      return MakeConstantString(IDecl->getIdentifier()->getName());
+  }
   // For Objective-C++, we want to provide the ability to catch both C++ and
   // Objective-C objects in the same function.
 
@@ -729,44 +811,6 @@
   return llvm::ConstantExpr::getBitCast(TI, PtrToInt8Ty);
 }
 
-llvm::Constant *CGObjCGNU::MakeConstantString(const std::string &Str,
-                                              const std::string &Name) {
-  llvm::Constant *ConstStr = CGM.GetAddrOfConstantCString(Str, Name.c_str());
-  return llvm::ConstantExpr::getGetElementPtr(ConstStr, Zeros, 2);
-}
-llvm::Constant *CGObjCGNU::ExportUniqueString(const std::string &Str,
-        const std::string prefix) {
-  std::string name = prefix + Str;
-  llvm::Constant *ConstStr = TheModule.getGlobalVariable(name);
-  if (!ConstStr) {
-    llvm::Constant *value = llvm::ConstantArray::get(VMContext, Str, true);
-    ConstStr = new llvm::GlobalVariable(TheModule, value->getType(), true,
-            llvm::GlobalValue::LinkOnceODRLinkage, value, prefix + Str);
-  }
-  return llvm::ConstantExpr::getGetElementPtr(ConstStr, Zeros, 2);
-}
-
-llvm::GlobalVariable *CGObjCGNU::MakeGlobal(const llvm::StructType *Ty,
-    std::vector<llvm::Constant*> &V, llvm::StringRef Name,
-    llvm::GlobalValue::LinkageTypes linkage) {
-  llvm::Constant *C = llvm::ConstantStruct::get(Ty, V);
-  return new llvm::GlobalVariable(TheModule, Ty, false,
-      linkage, C, Name);
-}
-
-llvm::GlobalVariable *CGObjCGNU::MakeGlobal(const llvm::ArrayType *Ty,
-    std::vector<llvm::Constant*> &V, llvm::StringRef Name,
-    llvm::GlobalValue::LinkageTypes linkage) {
-  llvm::Constant *C = llvm::ConstantArray::get(Ty, V);
-  return new llvm::GlobalVariable(TheModule, Ty, false,
-                                  linkage, C, Name);
-}
-llvm::GlobalVariable *CGObjCGNU::MakeGlobalArray(const llvm::Type *Ty,
-  std::vector<llvm::Constant*> &V, llvm::StringRef Name,
-  llvm::GlobalValue::LinkageTypes linkage) {
-  llvm::ArrayType *ArrayTy = llvm::ArrayType::get(Ty, V.size());
-  return MakeGlobal(ArrayTy, V, Name, linkage);
-}
 /// Generate an NSConstantString object.
 llvm::Constant *CGObjCGNU::GenerateConstantString(const StringLiteral *SL) {
 
@@ -2073,180 +2117,11 @@
   return EnumerationMutationFn;
 }
 
-namespace {
-  struct CallSyncExit : EHScopeStack::Cleanup {
-    llvm::Value *SyncExitFn;
-    llvm::Value *SyncArg;
-    CallSyncExit(llvm::Value *SyncExitFn, llvm::Value *SyncArg)
-      : SyncExitFn(SyncExitFn), SyncArg(SyncArg) {}
-
-    void Emit(CodeGenFunction &CGF, bool IsForEHCleanup) {
-      CGF.Builder.CreateCall(SyncExitFn, SyncArg)->setDoesNotThrow();
-    }
-  };
-}
-
 void CGObjCGNU::EmitSynchronizedStmt(CodeGenFunction &CGF,
                                      const ObjCAtSynchronizedStmt &S) {
-  // Evaluate the lock operand.  This should dominate the cleanup.
-  llvm::Value *SyncArg =
-    CGF.EmitScalarExpr(S.getSynchExpr());
-
-  // Acquire the lock.
-  SyncArg = CGF.Builder.CreateBitCast(SyncArg, IdTy);
-  CGF.Builder.CreateCall(SyncEnterFn, SyncArg);
-
-  // Register an all-paths cleanup to release the lock.
-  CGF.EHStack.pushCleanup<CallSyncExit>(NormalAndEHCleanup, SyncExitFn,
-      SyncArg);
-
-  // Emit the body of the statement.
-  CGF.EmitStmt(S.getSynchBody());
-
-  // Pop the lock-release cleanup.
-  CGF.PopCleanupBlock();
-}
-
-namespace {
-  struct CatchHandler {
-    const VarDecl *Variable;
-    const Stmt *Body;
-    llvm::BasicBlock *Block;
-    llvm::Value *TypeInfo;
-  };
-
-  struct CallObjCEndCatch : EHScopeStack::Cleanup {
-    CallObjCEndCatch(bool MightThrow, llvm::Value *Fn) :
-      MightThrow(MightThrow), Fn(Fn) {}
-    bool MightThrow;
-    llvm::Value *Fn;
-
-    void Emit(CodeGenFunction &CGF, bool IsForEH) {
-      if (!MightThrow) {
-        CGF.Builder.CreateCall(Fn)->setDoesNotThrow();
-        return;
-      }
-
-      CGF.EmitCallOrInvoke(Fn, 0, 0);
-    }
-  };
+  EmitAtSynchronizedStmt(CGF, S, SyncEnterFn, SyncExitFn);
 }
 
-void CGObjCGNU::EmitObjCXXTryStmt(CodeGenFunction &CGF,
-                                  const ObjCAtTryStmt &S) {
-  std::vector<const llvm::Type*> Args(1, PtrToInt8Ty);
-  llvm::FunctionType *FTy = llvm::FunctionType::get(PtrToInt8Ty, Args, false);
-  const llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext);
-
-  llvm::Constant *beginCatchFn =
-    CGM.CreateRuntimeFunction(FTy, "__cxa_begin_catch");
-
-  FTy = llvm::FunctionType::get(VoidTy, false);
-  llvm::Constant *endCatchFn =
-    CGM.CreateRuntimeFunction(FTy, "__cxa_end_catch");
-  FTy = llvm::FunctionType::get(VoidTy, Args, false);
-  llvm::Constant *exceptionRethrowFn =
-    CGM.CreateRuntimeFunction(FTy, "_Unwind_Resume_or_Rethrow");
-
-  // Jump destination for falling out of catch bodies.
-  CodeGenFunction::JumpDest Cont;
-  if (S.getNumCatchStmts())
-    Cont = CGF.getJumpDestInCurrentScope("eh.cont");
-
-  CodeGenFunction::FinallyInfo FinallyInfo;
-  if (const ObjCAtFinallyStmt *Finally = S.getFinallyStmt())
-    FinallyInfo = CGF.EnterFinallyBlock(Finally->getFinallyBody(),
-                                        beginCatchFn,
-                                        endCatchFn,
-                                        exceptionRethrowFn);
-
-  llvm::SmallVector<CatchHandler, 8> Handlers;
-
-  // Enter the catch, if there is one.
-  if (S.getNumCatchStmts()) {
-    for (unsigned I = 0, N = S.getNumCatchStmts(); I != N; ++I) {
-      const ObjCAtCatchStmt *CatchStmt = S.getCatchStmt(I);
-      const VarDecl *CatchDecl = CatchStmt->getCatchParamDecl();
-
-      Handlers.push_back(CatchHandler());
-      CatchHandler &Handler = Handlers.back();
-      Handler.Variable = CatchDecl;
-      Handler.Body = CatchStmt->getCatchBody();
-      Handler.Block = CGF.createBasicBlock("catch");
-
-      // @catch(...) always matches.
-      if (!CatchDecl) {
-        Handler.TypeInfo = 0; // catch-all
-        // Don't consider any other catches.
-        break;
-      }
-
-      Handler.TypeInfo = GetEHType(CatchDecl->getType());
-    }
-
-    EHCatchScope *Catch = CGF.EHStack.pushCatch(Handlers.size());
-    for (unsigned I = 0, E = Handlers.size(); I != E; ++I)
-      Catch->setHandler(I, Handlers[I].TypeInfo, Handlers[I].Block);
-  }
-  
-  // Emit the try body.
-  CGF.EmitStmt(S.getTryBody());
-
-  // Leave the try.
-  if (S.getNumCatchStmts())
-    CGF.EHStack.popCatch();
-
-  // Remember where we were.
-  CGBuilderTy::InsertPoint SavedIP = CGF.Builder.saveAndClearIP();
-
-  // Emit the handlers.
-  for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
-    CatchHandler &Handler = Handlers[I];
-
-    CGF.EmitBlock(Handler.Block);
-    llvm::Value *RawExn = CGF.Builder.CreateLoad(CGF.getExceptionSlot());
-
-    // Enter the catch.
-    llvm::CallInst *Exn =
-      CGF.Builder.CreateCall(beginCatchFn, RawExn,
-                             "exn.adjusted");
-    Exn->setDoesNotThrow();
-
-    // Add a cleanup to leave the catch.
-    bool EndCatchMightThrow = (Handler.Variable == 0);
-    CGF.EHStack.pushCleanup<CallObjCEndCatch>(NormalAndEHCleanup,
-                                              EndCatchMightThrow,
-                                              endCatchFn);
-
-    // Bind the catch parameter if it exists.
-    if (const VarDecl *CatchParam = Handler.Variable) {
-      const llvm::Type *CatchType = CGF.ConvertType(CatchParam->getType());
-      llvm::Value *CastExn = CGF.Builder.CreateBitCast(Exn, CatchType);
-
-      CGF.EmitAutoVarDecl(*CatchParam);
-      CGF.Builder.CreateStore(CastExn, CGF.GetAddrOfLocalVar(CatchParam));
-    }
-
-    CGF.ObjCEHValueStack.push_back(Exn);
-    CGF.EmitStmt(Handler.Body);
-    CGF.ObjCEHValueStack.pop_back();
-
-    // Leave the earlier cleanup.
-    CGF.PopCleanupBlock();
-
-    CGF.EmitBranchThroughCleanup(Cont);
-  }  
-
-  // Go back to the try-statement fallthrough.
-  CGF.Builder.restoreIP(SavedIP);
-
-  // Pop out of the normal cleanup on the finally.
-  if (S.getFinallyStmt())
-    CGF.ExitFinallyBlock(FinallyInfo);
-
-  if (Cont.isValid())
-    CGF.EmitBlock(Cont.getBlock());
-}
 
 void CGObjCGNU::EmitTryStmt(CodeGenFunction &CGF,
                             const ObjCAtTryStmt &S) {
@@ -2258,127 +2133,11 @@
   // catch handlers with calls to __blah_begin_catch/__blah_end_catch
   // (or even _Unwind_DeleteException), but probably doesn't
   // interoperate very well with foreign exceptions.
-
+  //
   // In Objective-C++ mode, we actually emit something equivalent to the C++
-  // exception handler.
-  if (CGM.getLangOptions().CPlusPlus) {
-    EmitObjCXXTryStmt(CGF, S);
-    return;
-  }
-
-  // Jump destination for falling out of catch bodies.
-  CodeGenFunction::JumpDest Cont;
-  if (S.getNumCatchStmts())
-    Cont = CGF.getJumpDestInCurrentScope("eh.cont");
-
-  // We handle @finally statements by pushing them as a cleanup
-  // before entering the catch.
-  CodeGenFunction::FinallyInfo FinallyInfo;
-  if (const ObjCAtFinallyStmt *Finally = S.getFinallyStmt()) {
-    FinallyInfo = CGF.EnterFinallyBlock(Finally->getFinallyBody(), 0, 0,
-                                        ExceptionThrowFn);
-  }
-
-  llvm::SmallVector<CatchHandler, 8> Handlers;
-
-  // Enter the catch, if there is one.
-  if (S.getNumCatchStmts()) {
-    for (unsigned I = 0, N = S.getNumCatchStmts(); I != N; ++I) {
-      const ObjCAtCatchStmt *CatchStmt = S.getCatchStmt(I);
-      const VarDecl *CatchDecl = CatchStmt->getCatchParamDecl();
-
-      Handlers.push_back(CatchHandler());
-      CatchHandler &Handler = Handlers.back();
-      Handler.Variable = CatchDecl;
-      Handler.Body = CatchStmt->getCatchBody();
-      Handler.Block = CGF.createBasicBlock("catch");
-
-      // @catch() and @catch(id) both catch any ObjC exception.
-      // Treat them as catch-alls.
-      // really be catching foreign exceptions?
-      
-      if (!CatchDecl) {
-        Handler.TypeInfo = 0; // catch-all
-        // Don't consider any other catches.
-        break;
-      }
-      if (CatchDecl->getType()->isObjCIdType()
-          || CatchDecl->getType()->isObjCQualifiedIdType()) {
-        // With the old ABI, there was only one kind of catchall, which broke
-        // foreign exceptions.  With the new ABI, we use __objc_id_typeinfo as
-        // a pointer indicating object catchalls, and NULL to indicate real
-        // catchalls
-        if (CGM.getLangOptions().ObjCNonFragileABI) {
-          Handler.TypeInfo = MakeConstantString("@id");
-          continue;
-        } else {
-          Handler.TypeInfo = 0; // catch-all
-          // Don't consider any other catches.
-          break;
-        }
-      }
-
-      // All other types should be Objective-C interface pointer types.
-      const ObjCObjectPointerType *OPT =
-        CatchDecl->getType()->getAs<ObjCObjectPointerType>();
-      assert(OPT && "Invalid @catch type.");
-      const ObjCInterfaceDecl *IDecl =
-        OPT->getObjectType()->getInterface();
-      assert(IDecl && "Invalid @catch type.");
-      Handler.TypeInfo = MakeConstantString(IDecl->getNameAsString());
-    }
-
-    EHCatchScope *Catch = CGF.EHStack.pushCatch(Handlers.size());
-    for (unsigned I = 0, E = Handlers.size(); I != E; ++I)
-      Catch->setHandler(I, Handlers[I].TypeInfo, Handlers[I].Block);
-  }
-  
-  // Emit the try body.
-  CGF.EmitStmt(S.getTryBody());
-
-  // Leave the try.
-  if (S.getNumCatchStmts())
-    CGF.EHStack.popCatch();
-
-  // Remember where we were.
-  CGBuilderTy::InsertPoint SavedIP = CGF.Builder.saveAndClearIP();
-
-  // Emit the handlers.
-  for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
-    CatchHandler &Handler = Handlers[I];
-    CGF.EmitBlock(Handler.Block);
-
-    llvm::Value *Exn = CGF.Builder.CreateLoad(CGF.getExceptionSlot());
-
-    // Bind the catch parameter if it exists.
-    if (const VarDecl *CatchParam = Handler.Variable) {
-      const llvm::Type *CatchType = CGF.ConvertType(CatchParam->getType());
-      Exn = CGF.Builder.CreateBitCast(Exn, CatchType);
-
-      CGF.EmitAutoVarDecl(*CatchParam);
-      CGF.Builder.CreateStore(Exn, CGF.GetAddrOfLocalVar(CatchParam));
-    }
-
-    CGF.ObjCEHValueStack.push_back(Exn);
-    CGF.EmitStmt(Handler.Body);
-    CGF.ObjCEHValueStack.pop_back();
-
-    CGF.EmitBranchThroughCleanup(Cont);
-  }  
-
-  // Go back to the try-statement fallthrough.
-  CGF.Builder.restoreIP(SavedIP);
-
-  // Pop out of the finally.
-  if (S.getFinallyStmt())
-    CGF.ExitFinallyBlock(FinallyInfo);
-
-  if (Cont.isValid()) {
-    if (Cont.getBlock()->use_empty())
-      delete Cont.getBlock();
-    else
-      CGF.EmitBlock(Cont.getBlock());
-  }
+  // exception handler. 
+  EmitTryCatchStmt(CGF, S, EnterCatchFn, ExitCatchFn, ExceptionReThrowFn);
+  return ;
 }
 
 void CGObjCGNU::EmitThrowStmt(CodeGenFunction &CGF,

Modified: cfe/trunk/lib/CodeGen/CGObjCMac.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGObjCMac.cpp?rev=128274&r1=128273&r2=128274&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGObjCMac.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGObjCMac.cpp Fri Mar 25 06:57:33 2011
@@ -42,9 +42,6 @@
 using namespace clang;
 using namespace CodeGen;
 
-// Common CGObjCRuntime functions, these don't belong here, but they
-// don't belong in CGObjCRuntime either so we will live with it for
-// now.
 
 static void EmitNullReturnInitialization(CodeGenFunction &CGF,
                                          ReturnValueSlot &returnSlot,
@@ -55,112 +52,6 @@
   CGF.EmitNullInitialization(returnSlot.getValue(), resultType);
 }
 
-static uint64_t LookupFieldBitOffset(CodeGen::CodeGenModule &CGM,
-                                     const ObjCInterfaceDecl *OID,
-                                     const ObjCImplementationDecl *ID,
-                                     const ObjCIvarDecl *Ivar) {
-  const ObjCInterfaceDecl *Container = Ivar->getContainingInterface();
-
-  // FIXME: We should eliminate the need to have ObjCImplementationDecl passed
-  // in here; it should never be necessary because that should be the lexical
-  // decl context for the ivar.
-
-  // If we know have an implementation (and the ivar is in it) then
-  // look up in the implementation layout.
-  const ASTRecordLayout *RL;
-  if (ID && ID->getClassInterface() == Container)
-    RL = &CGM.getContext().getASTObjCImplementationLayout(ID);
-  else
-    RL = &CGM.getContext().getASTObjCInterfaceLayout(Container);
-
-  // Compute field index.
-  //
-  // FIXME: The index here is closely tied to how ASTContext::getObjCLayout is
-  // implemented. This should be fixed to get the information from the layout
-  // directly.
-  unsigned Index = 0;
-  llvm::SmallVector<ObjCIvarDecl*, 16> Ivars;
-  CGM.getContext().ShallowCollectObjCIvars(Container, Ivars);
-  for (unsigned k = 0, e = Ivars.size(); k != e; ++k) {
-    if (Ivar == Ivars[k])
-      break;
-    ++Index;
-  }
-  assert(Index != Ivars.size() && "Ivar is not inside container!");
-  assert(Index < RL->getFieldCount() && "Ivar is not inside record layout!");
-
-  return RL->getFieldOffset(Index);
-}
-
-uint64_t CGObjCRuntime::ComputeIvarBaseOffset(CodeGen::CodeGenModule &CGM,
-                                              const ObjCInterfaceDecl *OID,
-                                              const ObjCIvarDecl *Ivar) {
-  return LookupFieldBitOffset(CGM, OID, 0, Ivar) / 8;
-}
-
-uint64_t CGObjCRuntime::ComputeIvarBaseOffset(CodeGen::CodeGenModule &CGM,
-                                              const ObjCImplementationDecl *OID,
-                                              const ObjCIvarDecl *Ivar) {
-  return LookupFieldBitOffset(CGM, OID->getClassInterface(), OID, Ivar) / 8;
-}
-
-LValue CGObjCRuntime::EmitValueForIvarAtOffset(CodeGen::CodeGenFunction &CGF,
-                                               const ObjCInterfaceDecl *OID,
-                                               llvm::Value *BaseValue,
-                                               const ObjCIvarDecl *Ivar,
-                                               unsigned CVRQualifiers,
-                                               llvm::Value *Offset) {
-  // Compute (type*) ( (char *) BaseValue + Offset)
-  const llvm::Type *I8Ptr = llvm::Type::getInt8PtrTy(CGF.getLLVMContext());
-  QualType IvarTy = Ivar->getType();
-  const llvm::Type *LTy = CGF.CGM.getTypes().ConvertTypeForMem(IvarTy);
-  llvm::Value *V = CGF.Builder.CreateBitCast(BaseValue, I8Ptr);
-  V = CGF.Builder.CreateInBoundsGEP(V, Offset, "add.ptr");
-  V = CGF.Builder.CreateBitCast(V, llvm::PointerType::getUnqual(LTy));
-
-  if (!Ivar->isBitField()) {
-    LValue LV = CGF.MakeAddrLValue(V, IvarTy);
-    LV.getQuals().addCVRQualifiers(CVRQualifiers);
-    return LV;
-  }
-
-  // We need to compute an access strategy for this bit-field. We are given the
-  // offset to the first byte in the bit-field, the sub-byte offset is taken
-  // from the original layout. We reuse the normal bit-field access strategy by
-  // treating this as an access to a struct where the bit-field is in byte 0,
-  // and adjust the containing type size as appropriate.
-  //
-  // FIXME: Note that currently we make a very conservative estimate of the
-  // alignment of the bit-field, because (a) it is not clear what guarantees the
-  // runtime makes us, and (b) we don't have a way to specify that the struct is
-  // at an alignment plus offset.
-  //
-  // Note, there is a subtle invariant here: we can only call this routine on
-  // non-synthesized ivars but we may be called for synthesized ivars.  However,
-  // a synthesized ivar can never be a bit-field, so this is safe.
-  const ASTRecordLayout &RL =
-    CGF.CGM.getContext().getASTObjCInterfaceLayout(OID);
-  uint64_t TypeSizeInBits = CGF.CGM.getContext().toBits(RL.getSize());
-  uint64_t FieldBitOffset = LookupFieldBitOffset(CGF.CGM, OID, 0, Ivar);
-  uint64_t BitOffset = FieldBitOffset % 8;
-  uint64_t ContainingTypeAlign = 8;
-  uint64_t ContainingTypeSize = TypeSizeInBits - (FieldBitOffset - BitOffset);
-  uint64_t BitFieldSize =
-    Ivar->getBitWidth()->EvaluateAsInt(CGF.getContext()).getZExtValue();
-
-  // Allocate a new CGBitFieldInfo object to describe this access.
-  //
-  // FIXME: This is incredibly wasteful, these should be uniqued or part of some
-  // layout object. However, this is blocked on other cleanups to the
-  // Objective-C code, so for now we just live with allocating a bunch of these
-  // objects.
-  CGBitFieldInfo *Info = new (CGF.CGM.getContext()) CGBitFieldInfo(
-    CGBitFieldInfo::MakeInfo(CGF.CGM.getTypes(), Ivar, BitOffset, BitFieldSize,
-                             ContainingTypeSize, ContainingTypeAlign));
-
-  return LValue::MakeBitfield(V, *Info,
-                              IvarTy.getCVRQualifiers() | CVRQualifiers);
-}
 
 ///
 

Added: cfe/trunk/lib/CodeGen/CGObjCRuntime.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGObjCRuntime.cpp?rev=128274&view=auto
==============================================================================
--- cfe/trunk/lib/CodeGen/CGObjCRuntime.cpp (added)
+++ cfe/trunk/lib/CodeGen/CGObjCRuntime.cpp Fri Mar 25 06:57:33 2011
@@ -0,0 +1,308 @@
+//==- CGObjCRuntime.cpp - Interface to Shared Objective-C Runtime Features ==//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This abstract class defines the interface for Objective-C runtime-specific
+// code generation.  It provides some concrete helper methods for functionality
+// shared between all (or most) of the Objective-C runtimes supported by clang.
+//
+//===----------------------------------------------------------------------===//
+
+#include "CGObjCRuntime.h"
+
+#include "CGRecordLayout.h"
+#include "CodeGenModule.h"
+#include "CodeGenFunction.h"
+#include "CGCleanup.h"
+
+#include "clang/AST/RecordLayout.h"
+#include "clang/AST/StmtObjC.h"
+
+#include "llvm/Support/CallSite.h"
+
+using namespace clang;
+using namespace CodeGen;
+
+static uint64_t LookupFieldBitOffset(CodeGen::CodeGenModule &CGM,
+                                     const ObjCInterfaceDecl *OID,
+                                     const ObjCImplementationDecl *ID,
+                                     const ObjCIvarDecl *Ivar) {
+  const ObjCInterfaceDecl *Container = Ivar->getContainingInterface();
+
+  // FIXME: We should eliminate the need to have ObjCImplementationDecl passed
+  // in here; it should never be necessary because that should be the lexical
+  // decl context for the ivar.
+
+  // If we know have an implementation (and the ivar is in it) then
+  // look up in the implementation layout.
+  const ASTRecordLayout *RL;
+  if (ID && ID->getClassInterface() == Container)
+    RL = &CGM.getContext().getASTObjCImplementationLayout(ID);
+  else
+    RL = &CGM.getContext().getASTObjCInterfaceLayout(Container);
+
+  // Compute field index.
+  //
+  // FIXME: The index here is closely tied to how ASTContext::getObjCLayout is
+  // implemented. This should be fixed to get the information from the layout
+  // directly.
+  unsigned Index = 0;
+  llvm::SmallVector<ObjCIvarDecl*, 16> Ivars;
+  CGM.getContext().ShallowCollectObjCIvars(Container, Ivars);
+  for (unsigned k = 0, e = Ivars.size(); k != e; ++k) {
+    if (Ivar == Ivars[k])
+      break;
+    ++Index;
+  }
+  assert(Index != Ivars.size() && "Ivar is not inside container!");
+  assert(Index < RL->getFieldCount() && "Ivar is not inside record layout!");
+
+  return RL->getFieldOffset(Index);
+}
+
+uint64_t CGObjCRuntime::ComputeIvarBaseOffset(CodeGen::CodeGenModule &CGM,
+                                              const ObjCInterfaceDecl *OID,
+                                              const ObjCIvarDecl *Ivar) {
+  return LookupFieldBitOffset(CGM, OID, 0, Ivar) / 8;
+}
+
+uint64_t CGObjCRuntime::ComputeIvarBaseOffset(CodeGen::CodeGenModule &CGM,
+                                              const ObjCImplementationDecl *OID,
+                                              const ObjCIvarDecl *Ivar) {
+  return LookupFieldBitOffset(CGM, OID->getClassInterface(), OID, Ivar) / 8;
+}
+
+LValue CGObjCRuntime::EmitValueForIvarAtOffset(CodeGen::CodeGenFunction &CGF,
+                                               const ObjCInterfaceDecl *OID,
+                                               llvm::Value *BaseValue,
+                                               const ObjCIvarDecl *Ivar,
+                                               unsigned CVRQualifiers,
+                                               llvm::Value *Offset) {
+  // Compute (type*) ( (char *) BaseValue + Offset)
+  const llvm::Type *I8Ptr = llvm::Type::getInt8PtrTy(CGF.getLLVMContext());
+  QualType IvarTy = Ivar->getType();
+  const llvm::Type *LTy = CGF.CGM.getTypes().ConvertTypeForMem(IvarTy);
+  llvm::Value *V = CGF.Builder.CreateBitCast(BaseValue, I8Ptr);
+  V = CGF.Builder.CreateInBoundsGEP(V, Offset, "add.ptr");
+  V = CGF.Builder.CreateBitCast(V, llvm::PointerType::getUnqual(LTy));
+
+  if (!Ivar->isBitField()) {
+    LValue LV = CGF.MakeAddrLValue(V, IvarTy);
+    LV.getQuals().addCVRQualifiers(CVRQualifiers);
+    return LV;
+  }
+
+  // We need to compute an access strategy for this bit-field. We are given the
+  // offset to the first byte in the bit-field, the sub-byte offset is taken
+  // from the original layout. We reuse the normal bit-field access strategy by
+  // treating this as an access to a struct where the bit-field is in byte 0,
+  // and adjust the containing type size as appropriate.
+  //
+  // FIXME: Note that currently we make a very conservative estimate of the
+  // alignment of the bit-field, because (a) it is not clear what guarantees the
+  // runtime makes us, and (b) we don't have a way to specify that the struct is
+  // at an alignment plus offset.
+  //
+  // Note, there is a subtle invariant here: we can only call this routine on
+  // non-synthesized ivars but we may be called for synthesized ivars.  However,
+  // a synthesized ivar can never be a bit-field, so this is safe.
+  const ASTRecordLayout &RL =
+    CGF.CGM.getContext().getASTObjCInterfaceLayout(OID);
+  uint64_t TypeSizeInBits = CGF.CGM.getContext().toBits(RL.getSize());
+  uint64_t FieldBitOffset = LookupFieldBitOffset(CGF.CGM, OID, 0, Ivar);
+  uint64_t BitOffset = FieldBitOffset % 8;
+  uint64_t ContainingTypeAlign = 8;
+  uint64_t ContainingTypeSize = TypeSizeInBits - (FieldBitOffset - BitOffset);
+  uint64_t BitFieldSize =
+    Ivar->getBitWidth()->EvaluateAsInt(CGF.getContext()).getZExtValue();
+
+  // Allocate a new CGBitFieldInfo object to describe this access.
+  //
+  // FIXME: This is incredibly wasteful, these should be uniqued or part of some
+  // layout object. However, this is blocked on other cleanups to the
+  // Objective-C code, so for now we just live with allocating a bunch of these
+  // objects.
+  CGBitFieldInfo *Info = new (CGF.CGM.getContext()) CGBitFieldInfo(
+    CGBitFieldInfo::MakeInfo(CGF.CGM.getTypes(), Ivar, BitOffset, BitFieldSize,
+                             ContainingTypeSize, ContainingTypeAlign));
+
+  return LValue::MakeBitfield(V, *Info,
+                              IvarTy.getCVRQualifiers() | CVRQualifiers);
+}
+
+namespace {
+  struct CatchHandler {
+    const VarDecl *Variable;
+    const Stmt *Body;
+    llvm::BasicBlock *Block;
+    llvm::Value *TypeInfo;
+  };
+
+  struct CallObjCEndCatch : EHScopeStack::Cleanup {
+    CallObjCEndCatch(bool MightThrow, llvm::Value *Fn) :
+      MightThrow(MightThrow), Fn(Fn) {}
+    bool MightThrow;
+    llvm::Value *Fn;
+
+    void Emit(CodeGenFunction &CGF, bool IsForEH) {
+      if (!MightThrow) {
+        CGF.Builder.CreateCall(Fn)->setDoesNotThrow();
+        return;
+      }
+
+      CGF.EmitCallOrInvoke(Fn, 0, 0);
+    }
+  };
+}
+
+
+void CGObjCRuntime::EmitTryCatchStmt(CodeGenFunction &CGF,
+                                     const ObjCAtTryStmt &S,
+                                     llvm::Function *beginCatchFn,
+                                     llvm::Function *endCatchFn,
+                                     llvm::Function *exceptionRethrowFn) {
+  // Jump destination for falling out of catch bodies.
+  CodeGenFunction::JumpDest Cont;
+  if (S.getNumCatchStmts())
+    Cont = CGF.getJumpDestInCurrentScope("eh.cont");
+
+  CodeGenFunction::FinallyInfo FinallyInfo;
+  if (const ObjCAtFinallyStmt *Finally = S.getFinallyStmt())
+    FinallyInfo = CGF.EnterFinallyBlock(Finally->getFinallyBody(),
+                                        beginCatchFn,
+                                        endCatchFn,
+                                        exceptionRethrowFn);
+
+  llvm::SmallVector<CatchHandler, 8> Handlers;
+
+  // Enter the catch, if there is one.
+  if (S.getNumCatchStmts()) {
+    for (unsigned I = 0, N = S.getNumCatchStmts(); I != N; ++I) {
+      const ObjCAtCatchStmt *CatchStmt = S.getCatchStmt(I);
+      const VarDecl *CatchDecl = CatchStmt->getCatchParamDecl();
+
+      Handlers.push_back(CatchHandler());
+      CatchHandler &Handler = Handlers.back();
+      Handler.Variable = CatchDecl;
+      Handler.Body = CatchStmt->getCatchBody();
+      Handler.Block = CGF.createBasicBlock("catch");
+
+      // @catch(...) always matches.
+      if (!CatchDecl) {
+        Handler.TypeInfo = 0; // catch-all
+        // Don't consider any other catches.
+        break;
+      }
+
+      Handler.TypeInfo = GetEHType(CatchDecl->getType());
+    }
+
+    EHCatchScope *Catch = CGF.EHStack.pushCatch(Handlers.size());
+    for (unsigned I = 0, E = Handlers.size(); I != E; ++I)
+      Catch->setHandler(I, Handlers[I].TypeInfo, Handlers[I].Block);
+  }
+  
+  // Emit the try body.
+  CGF.EmitStmt(S.getTryBody());
+
+  // Leave the try.
+  if (S.getNumCatchStmts())
+    CGF.EHStack.popCatch();
+
+  // Remember where we were.
+  CGBuilderTy::InsertPoint SavedIP = CGF.Builder.saveAndClearIP();
+
+  // Emit the handlers.
+  for (unsigned I = 0, E = Handlers.size(); I != E; ++I) {
+    CatchHandler &Handler = Handlers[I];
+
+    CGF.EmitBlock(Handler.Block);
+    llvm::Value *RawExn = CGF.Builder.CreateLoad(CGF.getExceptionSlot());
+
+    // Enter the catch.
+    llvm::Value *Exn = RawExn;
+    if (beginCatchFn) {
+      Exn = CGF.Builder.CreateCall(beginCatchFn, RawExn, "exn.adjusted");
+      cast<llvm::CallInst>(Exn)->setDoesNotThrow();
+    }
+
+    if (endCatchFn) {
+      // Add a cleanup to leave the catch.
+      bool EndCatchMightThrow = (Handler.Variable == 0);
+
+      CGF.EHStack.pushCleanup<CallObjCEndCatch>(NormalAndEHCleanup,
+                                                EndCatchMightThrow,
+                                                endCatchFn);
+    }
+
+    // Bind the catch parameter if it exists.
+    if (const VarDecl *CatchParam = Handler.Variable) {
+      const llvm::Type *CatchType = CGF.ConvertType(CatchParam->getType());
+      llvm::Value *CastExn = CGF.Builder.CreateBitCast(Exn, CatchType);
+
+      CGF.EmitAutoVarDecl(*CatchParam);
+      CGF.Builder.CreateStore(CastExn, CGF.GetAddrOfLocalVar(CatchParam));
+    }
+
+    CGF.ObjCEHValueStack.push_back(Exn);
+    CGF.EmitStmt(Handler.Body);
+    CGF.ObjCEHValueStack.pop_back();
+
+    // Leave the earlier cleanup.
+    if (endCatchFn) 
+      CGF.PopCleanupBlock();
+
+    CGF.EmitBranchThroughCleanup(Cont);
+  }  
+
+  // Go back to the try-statement fallthrough.
+  CGF.Builder.restoreIP(SavedIP);
+
+  // Pop out of the normal cleanup on the finally.
+  if (S.getFinallyStmt())
+    CGF.ExitFinallyBlock(FinallyInfo);
+
+  if (Cont.isValid())
+    CGF.EmitBlock(Cont.getBlock());
+}
+
+namespace {
+  struct CallSyncExit : EHScopeStack::Cleanup {
+    llvm::Value *SyncExitFn;
+    llvm::Value *SyncArg;
+    CallSyncExit(llvm::Value *SyncExitFn, llvm::Value *SyncArg)
+      : SyncExitFn(SyncExitFn), SyncArg(SyncArg) {}
+
+    void Emit(CodeGenFunction &CGF, bool IsForEHCleanup) {
+      CGF.Builder.CreateCall(SyncExitFn, SyncArg)->setDoesNotThrow();
+    }
+  };
+}
+
+void CGObjCRuntime::EmitAtSynchronizedStmt(CodeGenFunction &CGF,
+                                           const ObjCAtSynchronizedStmt &S,
+                                           llvm::Function *syncEnterFn,
+                                           llvm::Function *syncExitFn) {
+  // Evaluate the lock operand.  This should dominate the cleanup.
+  llvm::Value *SyncArg =
+    CGF.EmitScalarExpr(S.getSynchExpr());
+
+  // Acquire the lock.
+  SyncArg = CGF.Builder.CreateBitCast(SyncArg, syncEnterFn->getFunctionType()->getParamType(0));
+  CGF.Builder.CreateCall(syncEnterFn, SyncArg);
+
+  // Register an all-paths cleanup to release the lock.
+  CGF.EHStack.pushCleanup<CallSyncExit>(NormalAndEHCleanup, syncExitFn,
+      SyncArg);
+
+  // Emit the body of the statement.
+  CGF.EmitStmt(S.getSynchBody());
+
+  // Pop the lock-release cleanup.
+  CGF.PopCleanupBlock();
+}

Modified: cfe/trunk/lib/CodeGen/CGObjCRuntime.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGObjCRuntime.h?rev=128274&r1=128273&r2=128274&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGObjCRuntime.h (original)
+++ cfe/trunk/lib/CodeGen/CGObjCRuntime.h Fri Mar 25 06:57:33 2011
@@ -87,6 +87,26 @@
                                   const ObjCIvarDecl *Ivar,
                                   unsigned CVRQualifiers,
                                   llvm::Value *Offset);
+  /// Emits a try / catch statement.  This function is intended to be called by
+  /// subclasses, and provides a generic mechanism for generating these, which
+  /// should be usable by all runtimes.  The caller must provide the functions to
+  /// call when entering and exiting a @catch() block, and the function used to
+  /// rethrow exceptions.  If the begin and end catch functions are NULL, then
+  /// the function assumes that the EH personality function provides the
+  /// thrown object directly.
+  void EmitTryCatchStmt(CodeGenFunction &CGF,
+                        const ObjCAtTryStmt &S,
+                        llvm::Function *beginCatchFn,
+                        llvm::Function *endCatchFn,
+                        llvm::Function *exceptionRethrowFn);
+  /// Emits an @synchronize() statement, using the syncEnterFn and syncExitFn
+  /// arguments as the functions called to lock and unlock the object.  This
+  /// function can be called by subclasses that use zero-cost exception
+  /// handling.
+  void EmitAtSynchronizedStmt(CodeGenFunction &CGF,
+                            const ObjCAtSynchronizedStmt &S,
+                            llvm::Function *syncEnterFn,
+                            llvm::Function *syncExitFn);
 
 public:
   virtual ~CGObjCRuntime();





More information about the cfe-commits mailing list