R600: Add support for GROUP_BARRIER instruction

Reviewed-by: Vincent Lejeune<vljn at ovi.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185161 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/R600/R600MachineScheduler.cpp b/lib/Target/R600/R600MachineScheduler.cpp
index a330d88..acc1b4d 100644
--- a/lib/Target/R600/R600MachineScheduler.cpp
+++ b/lib/Target/R600/R600MachineScheduler.cpp
@@ -269,10 +269,14 @@
     }
 
     // Does the instruction take a whole IG ?
+    // XXX: Is it possible to add a helper function in R600InstrInfo that can
+    // be used here and in R600PacketizerList::isSoloInstruction() ?
     if(TII->isVector(*MI) ||
         TII->isCubeOp(MI->getOpcode()) ||
-        TII->isReductionOp(MI->getOpcode()))
+        TII->isReductionOp(MI->getOpcode()) ||
+        MI->getOpcode() == AMDGPU::GROUP_BARRIER) {
       return AluT_XYZW;
+    }
 
     // Is the result already assigned to a channel ?
     unsigned DestSubReg = MI->getOperand(0).getSubReg();