r205097 - ObjC: allow targets to decide when to use stret for blocks.

[Tim Northover]

Author: tnorthover
Date: Sat Mar 29 08:28:05 2014
New Revision: 205097

URL: http://llvm.org/viewvc/llvm-project?rev=205097&view=rev
Log:
ObjC: allow targets to decide when to use stret for blocks.

This was originally part of the ARM64 patch, but seems semantically
separate.

Modified:
    cfe/trunk/lib/CodeGen/CGBlocks.cpp
    cfe/trunk/lib/CodeGen/CGCall.cpp
    cfe/trunk/lib/CodeGen/CGObjCMac.cpp
    cfe/trunk/lib/CodeGen/CodeGenModule.h
    cfe/trunk/lib/CodeGen/TargetInfo.h

Modified: cfe/trunk/lib/CodeGen/CGBlocks.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGBlocks.cpp?rev=205097&r1=205096&r2=205097&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGBlocks.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGBlocks.cpp Sat Mar 29 08:28:05 2014
@@ -1121,7 +1121,7 @@ CodeGenFunction::GenerateBlockFunction(G
   const CGFunctionInfo &fnInfo = CGM.getTypes().arrangeFreeFunctionDeclaration(
       fnType->getReturnType(), args, fnType->getExtInfo(),
       fnType->isVariadic());
-  if (CGM.ReturnTypeUsesSRet(fnInfo))
+  if (CGM.ReturnSlotInterferesWithArgs(fnInfo))
     blockInfo.UsesStret = true;
 
   llvm::FunctionType *fnLLVMType = CGM.getTypes().GetFunctionType(fnInfo);

Modified: cfe/trunk/lib/CodeGen/CGCall.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGCall.cpp?rev=205097&r1=205096&r2=205097&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGCall.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGCall.cpp Sat Mar 29 08:28:05 2014
@@ -878,6 +878,11 @@ bool CodeGenModule::ReturnTypeUsesSRet(c
   return FI.getReturnInfo().isIndirect();
 }
 
+bool CodeGenModule::ReturnSlotInterferesWithArgs(const CGFunctionInfo &FI) {
+  return ReturnTypeUsesSRet(FI) &&
+         getTargetCodeGenInfo().doesReturnSlotInterfereWithArgs();
+}
+
 bool CodeGenModule::ReturnTypeUsesFPRet(QualType ResultType) {
   if (const BuiltinType *BT = ResultType->getAs<BuiltinType>()) {
     switch (BT->getKind()) {

Modified: cfe/trunk/lib/CodeGen/CGObjCMac.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGObjCMac.cpp?rev=205097&r1=205096&r2=205097&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGObjCMac.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGObjCMac.cpp Sat Mar 29 08:28:05 2014
@@ -1881,7 +1881,7 @@ CGObjCCommonMac::EmitMessageSend(CodeGen
   NullReturnState nullReturn;
 
   llvm::Constant *Fn = NULL;
-  if (CGM.ReturnTypeUsesSRet(MSI.CallInfo)) {
+  if (CGM.ReturnSlotInterferesWithArgs(MSI.CallInfo)) {
     if (!IsSuper) nullReturn.init(CGF, Arg0);
     Fn = (ObjCABI == 2) ?  ObjCTypes.getSendStretFn2(IsSuper)
       : ObjCTypes.getSendStretFn(IsSuper);
@@ -1892,6 +1892,10 @@ CGObjCCommonMac::EmitMessageSend(CodeGen
     Fn = (ObjCABI == 2) ? ObjCTypes.getSendFp2RetFn2(IsSuper)
       : ObjCTypes.getSendFp2retFn(IsSuper);
   } else {
+    // arm64 uses objc_msgSend for stret methods and yet null receiver check
+    // must be made for it.
+    if (!IsSuper && CGM.ReturnTypeUsesSRet(MSI.CallInfo))
+      nullReturn.init(CGF, Arg0);
     Fn = (ObjCABI == 2) ? ObjCTypes.getSendFn2(IsSuper)
       : ObjCTypes.getSendFn(IsSuper);
   }
@@ -6517,7 +6521,7 @@ CGObjCNonFragileABIMac::EmitVTableMessag
   // FIXME: don't use this for that.
   llvm::Constant *fn = 0;
   std::string messageRefName("\01l_");
-  if (CGM.ReturnTypeUsesSRet(MSI.CallInfo)) {
+  if (CGM.ReturnSlotInterferesWithArgs(MSI.CallInfo)) {
     if (isSuper) {
       fn = ObjCTypes.getMessageSendSuper2StretFixupFn();
       messageRefName += "objc_msgSendSuper2_stret_fixup";

Modified: cfe/trunk/lib/CodeGen/CodeGenModule.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenModule.h?rev=205097&r1=205096&r2=205097&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenModule.h (original)
+++ cfe/trunk/lib/CodeGen/CodeGenModule.h Sat Mar 29 08:28:05 2014
@@ -908,6 +908,10 @@ public:
   /// as a return type.
   bool ReturnTypeUsesSRet(const CGFunctionInfo &FI);
 
+  /// ReturnSlotInterferesWithArgs - Return true iff the given type uses an
+  /// argument slot when 'sret' is used as a return type.
+  bool ReturnSlotInterferesWithArgs(const CGFunctionInfo &FI);
+
   /// ReturnTypeUsesFPRet - Return true iff the given type uses 'fpret' when
   /// used as a return type.
   bool ReturnTypeUsesFPRet(QualType ResultType);

Modified: cfe/trunk/lib/CodeGen/TargetInfo.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/TargetInfo.h?rev=205097&r1=205096&r2=205097&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/TargetInfo.h (original)
+++ cfe/trunk/lib/CodeGen/TargetInfo.h Sat Mar 29 08:28:05 2014
@@ -123,6 +123,10 @@ namespace clang {
       return Ty;
     }
 
+    /// doesReturnSlotInterfereWithArgs - Return true if the target uses an
+    /// argument slot for an 'sret' type.
+    virtual bool doesReturnSlotInterfereWithArgs() const { return true; }
+
     /// Retrieve the address of a function to call immediately before
     /// calling objc_retainAutoreleasedReturnValue.  The
     /// implementation of objc_autoreleaseReturnValue sniffs the