[llvm] [AMDGPU] Fix selection of s_load_b96 on GFX11 (PR #108029)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,58 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=amdgcn -mcpu=gfx1100 < %s | FileCheck %s -check-prefix=GFX11
+; RUN: llc -mtriple=amdgcn -mcpu=gfx1200 < %s | FileCheck %s -check-prefix=GFX12
+
+define amdgpu_cs void @test_uniform_load_b96(i32 %arg) "amdgpu-flat-work-group-size"="1,1" {
+; GFX11-LABEL: test_uniform_load_b96:
+; GFX11:       ; %bb.0: ; %bb
+; GFX11-NEXT:    v_mov_b32_e32 v1, 0
+; GFX11-NEXT:    s_delay_alu instid0(VALU_DEP_1) | instskip(NEXT) | instid1(VALU_DEP_1)
+; GFX11-NEXT:    v_lshlrev_b64 v[0:1], 2, v[0:1]
+; GFX11-NEXT:    v_readfirstlane_b32 s0, v0
+; GFX11-NEXT:    s_delay_alu instid0(VALU_DEP_2)
+; GFX11-NEXT:    v_readfirstlane_b32 s1, v1
+; GFX11-NEXT:    v_mov_b32_e32 v0, 0
+; GFX11-NEXT:    v_mov_b32_e32 v1, 0
+; GFX11-NEXT:    s_clause 0x1
+; GFX11-NEXT:    s_load_b64 s[2:3], s[0:1], 0x0
+; GFX11-NEXT:    s_load_b32 s0, s[0:1], 0x8
+; GFX11-NEXT:    s_waitcnt lgkmcnt(0)
+; GFX11-NEXT:    v_mov_b32_e32 v2, s3
+; GFX11-NEXT:    s_delay_alu instid0(VALU_DEP_1)
+; GFX11-NEXT:    v_or3_b32 v2, s2, v2, s0
+; GFX11-NEXT:    global_store_b32 v[0:1], v2, off
+; GFX11-NEXT:    s_nop 0
+; GFX11-NEXT:    s_sendmsg sendmsg(MSG_DEALLOC_VGPRS)
+; GFX11-NEXT:    s_endpgm
+;
+; GFX12-LABEL: test_uniform_load_b96:
+; GFX12:       ; %bb.0: ; %bb
+; GFX12-NEXT:    v_mov_b32_e32 v1, 0
+; GFX12-NEXT:    s_delay_alu instid0(VALU_DEP_1) | instskip(NEXT) | instid1(VALU_DEP_1)
+; GFX12-NEXT:    v_lshlrev_b64_e32 v[0:1], 2, v[0:1]
+; GFX12-NEXT:    v_readfirstlane_b32 s0, v0
+; GFX12-NEXT:    s_delay_alu instid0(VALU_DEP_2)
+; GFX12-NEXT:    v_readfirstlane_b32 s1, v1
+; GFX12-NEXT:    v_mov_b32_e32 v0, 0
+; GFX12-NEXT:    v_mov_b32_e32 v1, 0
+; GFX12-NEXT:    s_load_b96 s[0:2], s[0:1], 0x0
+; GFX12-NEXT:    s_wait_kmcnt 0x0
+; GFX12-NEXT:    v_mov_b32_e32 v2, s0
+; GFX12-NEXT:    s_delay_alu instid0(VALU_DEP_1)
+; GFX12-NEXT:    v_or3_b32 v2, v2, s1, s2
+; 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
+bb:
+  %i = zext i32 %arg to i64
+  %i1 = getelementptr i32, ptr addrspace(1) null, i64 %i
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arsenm wrote:

non-null base pointer would be better 

https://github.com/llvm/llvm-project/pull/108029