[OpenCL] Add Sema checks for OpenCL 2.0 block

[pxli168]

Summary

Add Sema checks for opencl 2.0 new features: Block.
This patch is partitioned from http://reviews.llvm.org/D16047

[Anastasia]

include/clang/Basic/DiagnosticSemaKinds.td

7701

opencl -> OpenCL

7705

opencl -> OpenCL

lib/Sema/SemaDecl.cpp

6712

Could you write it a bit shorter, may be: Blocks with variadic arguments are not allowed.

6714

getLangOpts() -> LangOpts

Could you remove 'LangOpts.OpenCLVersion >= 200' because we can also enable Blocks with -fblocks flag.

6717

This seems redundant with T->isBlockPointerType() from above

lib/Sema/SemaExpr.cpp

6504

Can you shorten this comment too. I would just remove: "To support these behaviors, additional restrictions in addition to the above feature restrictions are:".

6507

Also could you remove 'getLangOpts().OpenCLVersion >= 200', see similar comment above.

6509

I suggest to unify with another check for OpenCL on line 6497 to have OpenCL bits all in one place.

10261

Block -> block

10262

Could you remove 'getLangOpts().OpenCLVersion >= 200' here too!

10311

Block -> block

lib/Sema/SemaType.cpp

2178

Could you change to "Arrays of blocks are not supported.".

test/SemaOpenCL/invalid-block.cl

12

array of block type ...

13

block type cannot ...

14

block type cannot ...

17

Actually I think pointers to blocks have to be disallowed too, but spec doesn't mention that although it forbids the dereferencing.

I will submit a bug to Khronos to clarify this.

[pxli168]

Block is an OpenCL v2.0 feature, I think all test should be handled only for CL2.0 or newer version.

lib/Sema/SemaDecl.cpp

6714

But this is a OpenCL v2.0 restriction, if we do not check about OpenCL version it seems meaningless.

lib/Sema/SemaExpr.cpp

6509

It seems move it to there may change the order of checking condition first.

test/SemaOpenCL/invalid-block.cl

17

I think it is reasonable, please add me in cc list. I will try to make a change here. But this may make deference test case hard to write.

BTW, the qualifier to workgroup pipe builtin functions is resolved by https://cvs.khronos.org/bugzilla/show_bug.cgi?id=15541.

[Anastasia]

lib/Sema/SemaDecl.cpp

6714

Yes, but you have to diagnose blocks correctly in all CL versions in which we accept blocks. When you come to this point here you should only care about checking whether blocks have variadic prototype or not. You should assume the parser did the right job to either accept or reject the block declaration earlier and also gave the right diagnostic.

It will be responsibility of a parser to correctly accept or reject blocks depending on a version. I will prepare a patch for it later on. Please see my related comment on the review: http://reviews.llvm.org/D16928

lib/Sema/SemaExpr.cpp

6509

What is the implication of that? Will we get errors in different order then?

[pxli168]

lib/Sema/SemaDecl.cpp

6714

I will change these, if we can restrict -fblock with -cl-std=CL2.x then there will be no problem by only checking LangOpts.OpenCL

lib/Sema/SemaExpr.cpp

6509

I think we should put operands check after condition check to keep the original logic.

[Anastasia]

LGTM!

[Anastasia]

test/SemaOpenCL/invalid-block.cl

17

Khronos bug: https://cvs.khronos.org/bugzilla/show_bug.cgi?id=15599

include/clang/Basic/DiagnosticSemaKinds.td

def err_opencl_return_value_with_address_space : Error<
   "return value cannot be qualified with address space">;
 def err_opencl_constant_no_init : Error<
   "variable in constant address space must be initialized">;
 def err_atomic_init_constant : Error<
   "atomic variable can only be assigned to a compile time constant"
   " in the declaration statement in the program scope">;
 def err_opencl_implicit_vector_conversion : Error<
   "implicit conversions between vector types (%0 and %1) are not permitted">;
+def err_opencl_dereferencing : Error<
+  "dereferencing pointer of type %0 is not allowed in OpenCL">;
+def err_opencl_block_proto_variadic : Error<
+  "invalid block prototype, variadic arguments are not allowed in OpenCL">;
+def err_opencl_invalid_type_array : Error<
+  "array of %0 type is invalid in OpenCL">;
+def err_opencl_ternary_with_block : Error<
+  "block type cannot be used as expression in ternary expression in OpenCL">;
 
 // OpenCL v2.0 s6.13.6 -- Builtin Pipe Functions
 def err_opencl_builtin_pipe_first_arg : Error<
   "first argument to %0 must be a pipe type">;
 def err_opencl_builtin_pipe_arg_num : Error<
     "invalid number of arguments to function: %0">;
 def err_opencl_builtin_pipe_invalid_arg : Error<
   "invalid argument type to function %0 (expecting %1)">;

lib/Sema/SemaDecl.cpp

void Sema::CheckVariableDeclarationType(VarDecl *NewVD) {
   }
 
   if (NewVD->isConstexpr() && !T->isDependentType() &&
       RequireLiteralType(NewVD->getLocation(), T,
                          diag::err_constexpr_var_non_literal)) {
     NewVD->setInvalidDecl();
     return;
   }
+
+  // OpenCL v2.0 s6.12.5 - Blocks with variadic arguments are not supported.
+  if (LangOpts.OpenCL && T->isBlockPointerType()) {
+    const BlockPointerType *BlkTy = T->getAs<BlockPointerType>();
+    const FunctionProtoType *FTy =
+        BlkTy->getPointeeType()->getAs<FunctionProtoType>();
+    if (FTy->isVariadic()) {
+      Diag(NewVD->getLocation(), diag::err_opencl_block_proto_variadic)
+          << T << NewVD->getSourceRange();
+      NewVD->setInvalidDecl();
+      return;
+    }
+  }
 }
 
 /// \brief Perform semantic checking on a newly-created variable
 /// declaration.
 ///
 /// This routine performs all of the type-checking required for a
 /// variable declaration once it has been built. It is used both to
 /// check variables after they have been parsed and their declarators

lib/Sema/SemaExpr.cpp

if (checkVectorResult(S, CondTy, VecResTy, QuestionLoc))
       return QualType();
     return VecResTy;
   }
 
   // Both operands are scalar.
   return OpenCLConvertScalarsToVectors(S, LHS, RHS, CondTy, QuestionLoc);
 }
 
+/// \brief Return true if the Expr is block type
+static bool checkBlockType(Sema &S, const Expr *E) {
+  if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
+    QualType Ty = CE->getCallee()->getType();
+    if (Ty->isBlockPointerType()) {
+      S.Diag(E->getExprLoc(), diag::err_opencl_ternary_with_block);
+      return true;
+    }
+  }
+  return false;
+}
+
 /// Note that LHS is not null here, even if this is the gnu "x ?: y" extension.
 /// In that case, LHS = cond.
 /// C99 6.5.15
 QualType Sema::CheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
                                         ExprResult &RHS, ExprValueKind &VK,
                                         ExprObjectKind &OK,
                                         SourceLocation QuestionLoc) {
 
QualType Sema::CheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
 
   QualType ResTy = UsualArithmeticConversions(LHS, RHS);
   if (LHS.isInvalid() || RHS.isInvalid())
     return QualType();
 
   QualType LHSTy = LHS.get()->getType();
   QualType RHSTy = RHS.get()->getType();
 
+  // OpenCL v2.0 s6.12.5 - Blocks cannot be used as expressions of the ternary
+  // selection operator (?:).
+  if (getLangOpts().OpenCL &&
+      (checkBlockType(*this, LHS.get()) | checkBlockType(*this, RHS.get()))) {
+    return QualType();
+  }
+
   // If both operands have arithmetic type, do the usual arithmetic conversions
   // to find a common type: C99 6.5.15p3,5.
   if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) {
     LHS = ImpCastExprToType(LHS.get(), ResTy, PrepareScalarCast(LHS, ResTy));
     RHS = ImpCastExprToType(RHS.get(), ResTy, PrepareScalarCast(RHS, ResTy));
 
     return ResTy;
   }
if (lval == Expr::LV_IncompleteVoidType) {
     // allow it in cases which are otherwise valid.
     // Example: "extern void x; void* y = &x;".
     Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange();
   }
 
   // If the operand has type "type", the result has type "pointer to type".
   if (op->getType()->isObjCObjectType())
     return Context.getObjCObjectPointerType(op->getType());
+
+  // OpenCL v2.0 s6.12.5 - The unary operators & cannot be used with a block.
+  if (getLangOpts().OpenCL && OrigOp.get()->getType()->isBlockPointerType()) {
+    Diag(OpLoc, diag::err_typecheck_unary_expr) << OrigOp.get()->getType()
+                                                << op->getSourceRange();
+    return QualType();
+  }
+
   return Context.getPointerType(op->getType());
 }
 
 static void RecordModifiableNonNullParam(Sema &S, const Expr *Exp) {
   const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Exp);
   if (!DRE)
     return;
   const Decl *D = DRE->getDecl();
static QualType CheckIndirectionOperand(Sema &S, Expr *Op, ExprValueKind &VK,
 
   if (isa<CXXReinterpretCastExpr>(Op)) {
     QualType OpOrigType = Op->IgnoreParenCasts()->getType();
     S.CheckCompatibleReinterpretCast(OpOrigType, OpTy, /*IsDereference*/true,
                                      Op->getSourceRange());
   }
 
   if (const PointerType *PT = OpTy->getAs<PointerType>())
+  {
     Result = PT->getPointeeType();
+    // OpenCL v2.0 s6.12.5 - The unary operators * cannot be used with a block.
+    if (S.getLangOpts().OpenCLVersion >= 200 && Result->isBlockPointerType()) {
+      S.Diag(OpLoc, diag::err_opencl_dereferencing) << OpTy
+                                                    << Op->getSourceRange();
+      return QualType();
+    }
+  }
   else if (const ObjCObjectPointerType *OPT =
              OpTy->getAs<ObjCObjectPointerType>())
     Result = OPT->getPointeeType();
   else {
     ExprResult PR = S.CheckPlaceholderExpr(Op);
     if (PR.isInvalid()) return QualType();
     if (PR.get() != Op)
       return CheckIndirectionOperand(S, PR.get(), VK, OpLoc);

lib/Sema/SemaType.cpp

if (T->isVariableArrayType()) {
                                   : diag::ext_c99_array_usage) << ASM;
   }
 
   if (T->isVariableArrayType()) {
     // Warn about VLAs for -Wvla.
     Diag(Loc, diag::warn_vla_used);
   }
 
+  // OpenCL v2.0 s6.12.5 - Arrays of blocks are not supported.
+  if (getLangOpts().OpenCL) {
+    const QualType ArrType = Context.getBaseElementType(T);
+    if (ArrType->isBlockPointerType()) {
+      Diag(Loc, diag::err_opencl_invalid_type_array) << ArrType;
+      return QualType();
+    }
+  }
+
   return T;
 }
 
 /// \brief Build an ext-vector type.
 ///
 /// Run the required checks for the extended vector type.
 QualType Sema::BuildExtVectorType(QualType T, Expr *ArraySize,
                                   SourceLocation AttrLoc) {

test/SemaOpenCL/invalid-block.cl

+// RUN: %clang_cc1 -verify -fblocks -cl-std=CL2.0 %s
+
+int (^BlkVariadic)(int, ...) = ^int(int I, ...) { // expected-error {{invalid block prototype, variadic arguments are not allowed in OpenCL}}
+  return 0;
+};
+
+typedef int (^BlkInt)(int);
+void f1(int i) {
+  BlkInt B1 = ^int(int I) {return 1;};
+  BlkInt B2 = ^int(int I) {return 2;};
+  BlkInt Arr[] = {B1, B2}; // expected-error {{array of 'BlkInt' (aka 'int (^)(int)') type is invalid in OpenCL}}
+  int tmp = i ? B1(i)      // expected-error {{block type cannot be used as expression in ternary expression in OpenCL}}
+              : B2(i);     // expected-error {{block type cannot be used as expression in ternary expression in OpenCL}}
+}
+
+void f2(BlkInt *BlockPtr) {
+  BlkInt B = ^int(int I) {return 1;};
+  BlkInt *P = &B; // expected-error {{invalid argument type 'BlkInt' (aka 'int (^)(int)') to unary expression}}
+  B = *BlockPtr;  // expected-error {{dereferencing pointer of type '__generic BlkInt *' (aka 'int (^__generic *)(int)') is not allowed in OpenCL}}
+}