[OpenCL] Enabling the usage of CLK_NULL_QUEUE as compare operand.

[echuraev]

Summary

Enabling the compression of CLK_NULL_QUEUE to variable of type queue_t.

[Anastasia]

lib/Sema/SemaExpr.cpp

9624

getLangOpts().OpenCL is redundant because getLangOpts().OpenCLVersion is only set for OpenCL.

I would like us to minimize number of this checks in the future.

test/CodeGenOpenCL/null_queue.cl

7

I think this doesn't handle initialization yet:

queue_t q = 0;

which should also be possible!

8

could we just compare directly to 0 to make it simpler?

9

Could we check for exactly two occurrences of icmp?

[Anastasia]

lib/Sema/SemaOverload.cpp

1784 ↗

(On Diff #81372)

Is this covered with testing? I have a feeling we might need a test with overloading functions here?

test/CodeGenOpenCL/null_queue.cl

13

I think it would make sense to have a negative test checking that all other integer literals are rejected.

14

Could we also add a function with a queue_t parameter and check that 0 is accepted to be passed in?

[Anastasia]

test/SemaOpenCL/queue_t_overload.cl

10 ↗

(On Diff #81742)

could we also add something non-convertible for queue i.e.

foo(1, src3);

[Anastasia]

LGTM! Thanks!

lib/Sema/SemaExpr.cpp

if (!IsRelational && RHSIsNull
     return ResultTy;
   }
   if (!IsRelational && LHSIsNull
       && LHSType->isIntegerType() && RHSType->isBlockPointerType()) {
     LHS = ImpCastExprToType(LHS.get(), RHSType, CK_NullToPointer);
     return ResultTy;
   }
 
+  if (getLangOpts().OpenCL && getLangOpts().OpenCLVersion >= 200) {
+    if (LHSIsNull && RHSType->isQueueT()) {
+      LHS = ImpCastExprToType(LHS.get(), RHSType, CK_NullToPointer);
+      return ResultTy;
+    }
+
+    if (LHSType->isQueueT() && RHSIsNull) {
+      RHS = ImpCastExprToType(RHS.get(), LHSType, CK_NullToPointer);
+      return ResultTy;
+    }
+  }
+
   return InvalidOperands(Loc, LHS, RHS);
 }
 
 
 // Return a signed type that is of identical size and number of elements.
 // For floating point vectors, return an integer type of identical size 
 // and number of elements.
 QualType Sema::GetSignedVectorType(QualType V) {

test/CodeGenOpenCL/null_queue.cl

+// RUN: %clang_cc1 -O0 -cl-std=CL2.0  -emit-llvm %s -o - | FileCheck %s
+extern queue_t get_default_queue();
+
+#define CLK_NULL_QUEUE 0
+
+bool f() {
+  return CLK_NULL_QUEUE == get_default_queue() &&
+         get_default_queue() == CLK_NULL_QUEUE;
+  // CHECK: icmp eq %opencl.queue_t* null, %{{.*}}
+}
+