[cfe-commits] r124332 - in /cfe/trunk: lib/CodeGen/CGDecl.cpp lib/CodeGen/CGExpr.cpp lib/CodeGen/CodeGenFunction.h test/CodeGenObjC/block-6.m

[Fariborz Jahanian]

Author: fjahanian
Date: Wed Jan 26 17:08:27 2011
New Revision: 124332

URL: http://llvm.org/viewvc/llvm-project?rev=124332&view=rev
Log:
Fixes an IRgen bug where __block variable is
referenced in the block-literal initializer
of that variable. // rdar://8893785

Added:
    cfe/trunk/test/CodeGenObjC/block-6.m
Modified:
    cfe/trunk/lib/CodeGen/CGDecl.cpp
    cfe/trunk/lib/CodeGen/CGExpr.cpp
    cfe/trunk/lib/CodeGen/CodeGenFunction.h

Modified: cfe/trunk/lib/CodeGen/CGDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDecl.cpp?rev=124332&r1=124331&r2=124332&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGDecl.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGDecl.cpp Wed Jan 26 17:08:27 2011
@@ -305,6 +305,15 @@
   return ByRefValueInfo.find(VD)->second.second;
 }
 
+llvm::Value *CodeGenFunction::BuildBlockByrefAddress(llvm::Value *BaseAddr,
+                                                     const VarDecl *V) {
+  llvm::Value *Loc = Builder.CreateStructGEP(BaseAddr, 1, "forwarding");
+  Loc = Builder.CreateLoad(Loc);
+  Loc = Builder.CreateStructGEP(Loc, getByRefValueLLVMField(V),
+                                V->getNameAsString());
+  return Loc;
+}
+
 /// BuildByRefType - This routine changes a __block variable declared as T x
 ///   into:
 ///
@@ -795,9 +804,6 @@
     SpecialInit(*this, D, DeclPtr);
   } else if (Init) {
     llvm::Value *Loc = DeclPtr;
-    if (isByRef)
-      Loc = Builder.CreateStructGEP(DeclPtr, getByRefValueLLVMField(&D), 
-                                    D.getNameAsString());
     
     bool isVolatile = getContext().getCanonicalType(Ty).isVolatileQualified();
     
@@ -844,13 +850,31 @@
       }
     } else if (Ty->isReferenceType()) {
       RValue RV = EmitReferenceBindingToExpr(Init, &D);
+      if (isByRef)
+        Loc = Builder.CreateStructGEP(DeclPtr, getByRefValueLLVMField(&D), 
+                                      D.getNameAsString());
       EmitStoreOfScalar(RV.getScalarVal(), Loc, false, Alignment, Ty);
     } else if (!hasAggregateLLVMType(Init->getType())) {
       llvm::Value *V = EmitScalarExpr(Init);
+      if (isByRef) {
+        // When RHS has side-effect, must go through "forwarding' field
+        // to get to the address of the __block variable descriptor.
+        if (Init->HasSideEffects(getContext()))
+          Loc = BuildBlockByrefAddress(DeclPtr, &D);
+        else
+          Loc = Builder.CreateStructGEP(DeclPtr, getByRefValueLLVMField(&D), 
+                                        D.getNameAsString());
+      }
       EmitStoreOfScalar(V, Loc, isVolatile, Alignment, Ty);
     } else if (Init->getType()->isAnyComplexType()) {
+      if (isByRef)
+        Loc = Builder.CreateStructGEP(DeclPtr, getByRefValueLLVMField(&D), 
+                                      D.getNameAsString());
       EmitComplexExprIntoAddr(Init, Loc, isVolatile);
     } else {
+      if (isByRef)
+        Loc = Builder.CreateStructGEP(DeclPtr, getByRefValueLLVMField(&D), 
+                                      D.getNameAsString());
       EmitAggExpr(Init, AggValueSlot::forAddr(Loc, isVolatile, true, false));
     }
   }

Modified: cfe/trunk/lib/CodeGen/CGExpr.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGExpr.cpp?rev=124332&r1=124331&r2=124332&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGExpr.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGExpr.cpp Wed Jan 26 17:08:27 2011
@@ -1164,12 +1164,9 @@
       V = CGM.getStaticLocalDeclAddress(VD);
     assert(V && "DeclRefExpr not entered in LocalDeclMap?");
 
-    if (VD->hasAttr<BlocksAttr>()) {
-      V = Builder.CreateStructGEP(V, 1, "forwarding");
-      V = Builder.CreateLoad(V);
-      V = Builder.CreateStructGEP(V, getByRefValueLLVMField(VD),
-                                  VD->getNameAsString());
-    }
+    if (VD->hasAttr<BlocksAttr>())
+      V = BuildBlockByrefAddress(V, VD);
+    
     if (VD->getType()->isReferenceType())
       V = Builder.CreateLoad(V, "tmp");
 

Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.h?rev=124332&r1=124331&r2=124332&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenFunction.h (original)
+++ cfe/trunk/lib/CodeGen/CodeGenFunction.h Wed Jan 26 17:08:27 2011
@@ -811,7 +811,11 @@
   /// getByrefValueFieldNumber - Given a declaration, returns the LLVM field
   /// number that holds the value.
   unsigned getByRefValueLLVMField(const ValueDecl *VD) const;
-  
+
+  /// BuildBlockByrefAddress - Computes address location of the
+  /// variable which is declared as __block.
+  llvm::Value *BuildBlockByrefAddress(llvm::Value *BaseAddr,
+                                      const VarDecl *V);
 private:
   CGDebugInfo *DebugInfo;
 

Added: cfe/trunk/test/CodeGenObjC/block-6.m
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenObjC/block-6.m?rev=124332&view=auto
==============================================================================
--- cfe/trunk/test/CodeGenObjC/block-6.m (added)
+++ cfe/trunk/test/CodeGenObjC/block-6.m Wed Jan 26 17:08:27 2011
@@ -0,0 +1,12 @@
+// RUN: %clang_cc1 %s -emit-llvm -o - -fblocks -triple x86_64-apple-darwin10 | FileCheck %s
+// rdar://8893785
+
+void MYFUNC() {
+// CHECK: [[T1:%.*]] = bitcast i8* ()*
+// CHECK-NEXT: [[FORWARDING:%.*]] = getelementptr inbounds [[N_T:%.*]]* [[N:%.*]], i32 0, i32 1
+// CHECK-NEXT: [[T0:%.*]] = load [[N_T]]** [[FORWARDING]]
+// CHECK-NEXT: [[OBSERVER:%.*]] = getelementptr inbounds [[N_T]]* [[T0]], i32 0, i32 6
+// CHECK-NEXT: store i8* [[T1]], i8** [[OBSERVER]]
+  __block id observer = ^{ return observer; };
+}
+