AMDGPU: wave_barrier is not isBarrier

This is not a control flow instruction, so should not be marked as
isBarrier. This fixes a verifier error if followed by unreachable.

llvm-svn: 357081

2 files changed, 12 insertions, 1 deletions

diff --git a/llvm/lib/Target/AMDGPU/SIInstructions.td b/llvm/lib/Target/AMDGPU/SIInstructions.td
index b0ab7032d97..c3fa1bb41ef 100644
--- a/llvm/lib/Target/AMDGPU/SIInstructions.td
+++ b/llvm/lib/Target/AMDGPU/SIInstructions.td
@@ -197,7 +197,6 @@ def WAVE_BARRIER : SPseudoInstSI<(outs), (ins),
   let hasSideEffects = 1;
   let mayLoad = 1;
   let mayStore = 1;
-  let isBarrier = 1;
   let isConvergent = 1;
   let FixedSize = 1;
   let Size = 0;
diff --git a/llvm/test/CodeGen/AMDGPU/llvm.amdgcn.wave.barrier.ll b/llvm/test/CodeGen/AMDGPU/llvm.amdgcn.wave.barrier.ll
index e305f8eff58..be144b441a1 100644
--- a/llvm/test/CodeGen/AMDGPU/llvm.amdgcn.wave.barrier.ll
+++ b/llvm/test/CodeGen/AMDGPU/llvm.amdgcn.wave.barrier.ll
@@ -10,6 +10,18 @@ entry:
   ret void
 }
 
+; Check for verifier error from interpreting wave_barrier as a control
+; flow barrier.
+
+; GCN-LABEL: {{^}}test_wave_barrier_is_not_isBarrier:
+; GCN-DAG: ; wave barrier
+; GCN-NOT: s_barrier
+define amdgpu_kernel void @test_wave_barrier_is_not_isBarrier() #0 {
+entry:
+  call void @llvm.amdgcn.wave.barrier() #1
+  unreachable
+}
+
 declare void @llvm.amdgcn.wave.barrier() #1
 
 attributes #0 = { nounwind }