[llvm] [AMDGCN] Allow unscheduling of bundled insns (PR #129769)

[Austin Kerbow via llvm-commits]

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@@ -0,0 +1,18 @@
+; REQUIRES: asserts
+; RUN: llc -mtriple=amdgcn -O1 -mcpu=gfx90a -debug-only=machine-scheduler -filetype=null < %s 2>&1 | FileCheck --check-prefix=DEBUG %s
+
+; DEBUG: Attempting to revert scheduling.
+
+ at G = global <32 x i8> splat (i8 1)
+ at G.1 = global <32 x i8> splat (i8 127)
+
+define amdgpu_kernel void @gws_sema_v_offset0(i32 %val, <32 x i1>* %inp) #0 {
+  %LGV1 = load <32 x i8>, ptr @G.1, align 32
+  %LGV = load <32 x i8>, ptr @G, align 32
+  call void @llvm.amdgcn.ds.gws.sema.v(i32 0)
+  %C = icmp ne <32 x i8> %LGV, %LGV1
+  store <32 x i1> %C, ptr %inp, align 4
+  ret void
+}
+
+declare void @llvm.amdgcn.ds.gws.sema.v(i32) #1
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kerbowa wrote:

```suggestion
declare void @llvm.amdgcn.ds.gws.sema.v(i32)
```

https://github.com/llvm/llvm-project/pull/129769