[llvm] [AMDGPU] Optimize out s_barrier_signal/_wait (PR #116993)

[Diana Picus via llvm-commits]

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@@ -0,0 +1,55 @@
+; RUN: llc -global-isel=0 -mtriple=amdgcn -mcpu=gfx1200 < %s | FileCheck %s
+; RUN: llc -global-isel=1 -mtriple=amdgcn -mcpu=gfx1200 < %s | FileCheck %s
+
+; CHECK-LABEL: {{^}}signal_unknown_wgs:
+; CHECK: s_barrier_signal
+define amdgpu_kernel void @signal_unknown_wgs() {
+  tail call void @llvm.amdgcn.s.barrier.signal(i32 -1)
+  ret void
+}
+
+; CHECK-LABEL: {{^}}signal_flat_wgs_attr_32_128:
+; CHECK: s_barrier_signal
+define amdgpu_kernel void @signal_flat_wgs_attr_32_128() #1 {
+  tail call void @llvm.amdgcn.s.barrier.signal(i32 -1)
+  ret void
+}
+
+; CHECK-LABEL: {{^}}signal_flat_wgs_attr_16_32:
+; CHECK: :
+; CHECK-NEXT: s_endpgm
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rovka wrote:

Nit: Would it be more robust to `CHECK-NOT: barrier` instead?

https://github.com/llvm/llvm-project/pull/116993