[llvm] AMDGPU/GFX12: Fix s_barrier_signal_isfirst for single-wave workgroups (PR #143634)

[Matt Arsenault via llvm-commits]

Nicolai =?utf-8?q?Hähnle?= <nicolai.haehnle at amd.com>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/143634 at github.com>


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@@ -0,0 +1,41 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -global-isel=0 -mtriple=amdgcn -mcpu=gfx1200 -verify-machineinstrs < %s | FileCheck -check-prefixes=GFX12-SDAG %s
+; RUN: llc -global-isel=1 -mtriple=amdgcn -mcpu=gfx1200 -verify-machineinstrs < %s | FileCheck -check-prefixes=GFX12-GISEL %s
+
+define i1 @func1() {
+; GFX12-SDAG-LABEL: func1:
+; GFX12-SDAG:       ; %bb.0:
+; GFX12-SDAG-NEXT:    s_wait_loadcnt_dscnt 0x0
+; GFX12-SDAG-NEXT:    s_wait_expcnt 0x0
+; GFX12-SDAG-NEXT:    s_wait_samplecnt 0x0
+; GFX12-SDAG-NEXT:    s_wait_bvhcnt 0x0
+; GFX12-SDAG-NEXT:    s_wait_kmcnt 0x0
+; GFX12-SDAG-NEXT:    s_cmp_eq_u32 0, 0
+; GFX12-SDAG-NEXT:    s_wait_storecnt 0x0
+; GFX12-SDAG-NEXT:    s_barrier_signal_isfirst -1
+; GFX12-SDAG-NEXT:    s_cselect_b32 s0, -1, 0
+; GFX12-SDAG-NEXT:    s_wait_alu 0xfffe
+; GFX12-SDAG-NEXT:    v_cndmask_b32_e64 v0, 0, 1, s0
+; GFX12-SDAG-NEXT:    s_wait_kmcnt 0x0
+; GFX12-SDAG-NEXT:    s_setpc_b64 s[30:31]
+;
+; GFX12-GISEL-LABEL: func1:
+; GFX12-GISEL:       ; %bb.0:
+; GFX12-GISEL-NEXT:    s_wait_loadcnt_dscnt 0x0
+; GFX12-GISEL-NEXT:    s_wait_expcnt 0x0
+; GFX12-GISEL-NEXT:    s_wait_samplecnt 0x0
+; GFX12-GISEL-NEXT:    s_wait_bvhcnt 0x0
+; GFX12-GISEL-NEXT:    s_wait_kmcnt 0x0
+; GFX12-GISEL-NEXT:    s_cmp_eq_u32 0, 0
+; GFX12-GISEL-NEXT:    s_wait_storecnt 0x0
+; GFX12-GISEL-NEXT:    s_barrier_signal_isfirst -1
+; GFX12-GISEL-NEXT:    s_cselect_b32 s0, 1, 0
+; GFX12-GISEL-NEXT:    s_wait_alu 0xfffe
+; GFX12-GISEL-NEXT:    v_mov_b32_e32 v0, s0
+; GFX12-GISEL-NEXT:    s_wait_kmcnt 0x0
+; GFX12-GISEL-NEXT:    s_setpc_b64 s[30:31]
+    %r = call i1 @llvm.amdgcn.s.barrier.signal.isfirst(i32 -1)
+    ret i1 %r
----------------
arsenm wrote:

```suggestion
  %r = call i1 @llvm.amdgcn.s.barrier.signal.isfirst(i32 -1)
  ret i1 %r
```

https://github.com/llvm/llvm-project/pull/143634