[llvm] [AMDGPU] Architected SGPRs for GFX12 (PR #76140)

[Nicolai Hähnle via llvm-commits]

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@@ -0,0 +1,34 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 2
+; RUN: llc -mtriple=amdgcn-amd-amdpal -mcpu=gfx900 -mattr=+architected-sgprs --verify-machineinstrs < %s | FileCheck -check-prefixes=GFX9,GFX9-SDAG %s
+; RUN: llc -mtriple=amdgcn-amd-amdpal -mcpu=gfx900 -mattr=+architected-sgprs -global-isel --verify-machineinstrs < %s | FileCheck -check-prefixes=GFX9,GFX9-GISEL %s
+; RUN: llc -mtriple=amdgcn-amd-amdpal -mcpu=gfx1200 --verify-machineinstrs < %s | FileCheck -check-prefixes=GFX12,GFX12-SDAG %s
+; RUN: llc -mtriple=amdgcn-amd-amdpal -mcpu=gfx1200 -global-isel --verify-machineinstrs < %s | FileCheck -check-prefixes=GFX12,GFX12-GISEL %s
+
+define amdgpu_cs void @test_wave_id(ptr addrspace(1) %out) {
+; GFX9-LABEL: test_wave_id:
+; GFX9:       ; %bb.0:
+; GFX9-NEXT:    s_bfe_u32 s0, ttmp8, 0x50019
+; GFX9-NEXT:    v_mov_b32_e32 v2, s0
+; GFX9-NEXT:    global_store_dword v[0:1], v2, off
+; GFX9-NEXT:    s_endpgm
+;
+; GFX12-LABEL: test_wave_id:
+; GFX12:       ; %bb.0:
+; GFX12-NEXT:    s_bfe_u32 s0, ttmp8, 0x50019
+; GFX12-NEXT:    s_delay_alu instid0(SALU_CYCLE_1)
+; GFX12-NEXT:    v_mov_b32_e32 v2, s0
+; GFX12-NEXT:    global_store_b32 v[0:1], v2, off
+; GFX12-NEXT:    s_nop 0
+; GFX12-NEXT:    s_sendmsg sendmsg(MSG_DEALLOC_VGPRS)
+; GFX12-NEXT:    s_endpgm
+  %waveid = call i32 @llvm.amdgcn.wave.id()
+  store i32 %waveid, ptr addrspace(1) %out
+  ret void
+}
+
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nhaehnle wrote:

Yes, that ought to work in the exact same way since we never change ttmp registers from "user" (non-trap) code.

https://github.com/llvm/llvm-project/pull/76140