[llvm] [AMDGPU] Make chain functions receive a stack pointer (PR #184616)

[Diana Picus via llvm-commits]

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@@ -90,27 +153,27 @@ define amdgpu_cs_chain void @test_alloca_var(i32 %count) {
 ; GFX12-NEXT:    s_wait_bvhcnt 0x0
 ; GFX12-NEXT:    s_wait_kmcnt 0x0
 ; GFX12-NEXT:    v_lshl_add_u32 v0, v8, 2, 15
-; GFX12-NEXT:    s_mov_b32 s1, exec_lo
-; GFX12-NEXT:    s_mov_b32 s0, 0
-; GFX12-NEXT:    s_mov_b32 s32, 16
-; GFX12-NEXT:    s_delay_alu instid0(VALU_DEP_1)
+; GFX12-NEXT:    s_mov_b64 s[0:1], exec
+; GFX12-NEXT:    s_mov_b32 s2, 0
+; GFX12-NEXT:    s_mov_b32 s33, s32
+; GFX12-NEXT:    s_add_co_i32 s32, s32, 16
 ; GFX12-NEXT:    v_and_b32_e32 v1, -16, v0
 ; GFX12-NEXT:    v_mov_b32_e32 v0, 0
-; GFX12-NEXT:  .LBB2_1: ; =>This Inner Loop Header: Depth=1
+; GFX12-NEXT:  .LBB3_1: ; =>This Inner Loop Header: Depth=1
 ; GFX12-NEXT:    s_wait_alu depctr_sa_sdst(0)
-; GFX12-NEXT:    s_ctz_i32_b32 s2, s1
+; GFX12-NEXT:    s_ctz_i32_b64 s3, s[0:1]
 ; GFX12-NEXT:    s_wait_alu depctr_sa_sdst(0)
-; GFX12-NEXT:    v_readlane_b32 s3, v1, s2
-; GFX12-NEXT:    s_bitset0_b32 s1, s2
-; GFX12-NEXT:    s_max_u32 s0, s0, s3
+; GFX12-NEXT:    v_readlane_b32 s4, v1, s3
+; GFX12-NEXT:    s_bitset0_b64 s[0:1], s3
+; GFX12-NEXT:    s_max_u32 s2, s2, s4
 ; GFX12-NEXT:    s_wait_alu depctr_sa_sdst(0)
-; GFX12-NEXT:    s_cmp_lg_u32 s1, 0
-; GFX12-NEXT:    s_cbranch_scc1 .LBB2_1
+; GFX12-NEXT:    s_cmp_lg_u64 s[0:1], 0
+; GFX12-NEXT:    s_cbranch_scc1 .LBB3_1
 ; GFX12-NEXT:  ; %bb.2:
-; GFX12-NEXT:    s_mov_b32 s1, s32
+; GFX12-NEXT:    s_mov_b32 s0, s32
 ; GFX12-NEXT:    s_wait_alu depctr_sa_sdst(0)
-; GFX12-NEXT:    v_lshl_add_u32 v1, s0, 5, s1
-; GFX12-NEXT:    scratch_store_b32 off, v0, s1
+; GFX12-NEXT:    v_lshl_add_u32 v1, s2, 6, s0
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rovka wrote:

It has, that's part of the patch :) The thing is that GFX12 and GFX942 have different default wave sizes, but the IR needs to use the correct iN type for the EXEC mask received by the chain intrinsic. So the RUN lines need to agree. I opted to change the GFX12 run line to use wave64. 

https://github.com/llvm/llvm-project/pull/184616