[llvm] [AMDGPU] Filter candidates of LiveRegOptimizer for profitable cases (PR #124624)

[Jeffrey Byrnes via llvm-commits]

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@@ -406,32 +2052,60 @@ define amdgpu_kernel void @v8i8_phi_chain(ptr addrspace(1) %src1, ptr addrspace(
 ; GFX906-LABEL: v8i8_phi_chain:
 ; GFX906:       ; %bb.0: ; %entry
 ; GFX906-NEXT:    s_load_dwordx8 s[8:15], s[4:5], 0x24
-; GFX906-NEXT:    v_lshlrev_b32_e32 v3, 3, v0
+; GFX906-NEXT:    v_lshlrev_b32_e32 v9, 3, v0
 ; GFX906-NEXT:    v_cmp_lt_u32_e64 s[0:1], 14, v0
 ; GFX906-NEXT:    v_cmp_gt_u32_e32 vcc, 15, v0
 ; GFX906-NEXT:    s_waitcnt lgkmcnt(0)
-; GFX906-NEXT:    global_load_dwordx2 v[1:2], v3, s[8:9]
+; GFX906-NEXT:    global_load_dwordx2 v[1:2], v9, s[8:9]
+; GFX906-NEXT:    s_waitcnt vmcnt(0)
+; GFX906-NEXT:    v_lshrrev_b32_e32 v5, 24, v2
+; GFX906-NEXT:    v_lshrrev_b32_e32 v3, 16, v2
+; GFX906-NEXT:    v_lshrrev_b32_e32 v6, 8, v2
+; GFX906-NEXT:    v_lshrrev_b32_e32 v7, 24, v1
+; GFX906-NEXT:    v_lshrrev_b32_e32 v4, 16, v1
+; GFX906-NEXT:    v_lshrrev_b32_e32 v8, 8, v1
 ; GFX906-NEXT:    s_and_saveexec_b64 s[2:3], vcc
 ; GFX906-NEXT:    s_cbranch_execz .LBB8_2
 ; GFX906-NEXT:  ; %bb.1: ; %bb.1
-; GFX906-NEXT:    global_load_dwordx2 v[1:2], v3, s[10:11]
+; GFX906-NEXT:    global_load_dwordx2 v[1:2], v9, s[10:11]
 ; GFX906-NEXT:    v_cmp_gt_u32_e32 vcc, 7, v0
 ; GFX906-NEXT:    s_andn2_b64 s[0:1], s[0:1], exec
 ; GFX906-NEXT:    s_and_b64 s[4:5], vcc, exec
 ; GFX906-NEXT:    s_or_b64 s[0:1], s[0:1], s[4:5]
+; GFX906-NEXT:    s_waitcnt vmcnt(0)
+; GFX906-NEXT:    v_lshrrev_b32_e32 v5, 24, v2
+; GFX906-NEXT:    v_lshrrev_b32_e32 v3, 16, v2
+; GFX906-NEXT:    v_lshrrev_b32_e32 v6, 8, v2
+; GFX906-NEXT:    v_lshrrev_b32_e32 v7, 24, v1
+; GFX906-NEXT:    v_lshrrev_b32_e32 v4, 16, v1
+; GFX906-NEXT:    v_lshrrev_b32_e32 v8, 8, v1
 ; GFX906-NEXT:  .LBB8_2: ; %Flow
 ; GFX906-NEXT:    s_or_b64 exec, exec, s[2:3]
+; GFX906-NEXT:    v_lshlrev_b16_e32 v8, 8, v8
+; GFX906-NEXT:    v_lshlrev_b16_e32 v7, 8, v7
+; GFX906-NEXT:    v_lshlrev_b16_e32 v0, 8, v6
+; GFX906-NEXT:    v_lshlrev_b16_e32 v5, 8, v5
 ; GFX906-NEXT:    s_and_saveexec_b64 s[2:3], s[0:1]
 ; GFX906-NEXT:    s_cbranch_execz .LBB8_4
 ; GFX906-NEXT:  ; %bb.3: ; %bb.2
-; GFX906-NEXT:    v_mov_b32_e32 v0, 0
-; GFX906-NEXT:    s_waitcnt vmcnt(0)
-; GFX906-NEXT:    global_store_dwordx2 v0, v[1:2], s[12:13]
+; GFX906-NEXT:    v_or_b32_sdwa v9, v1, v8 dst_sel:DWORD dst_unused:UNUSED_PAD src0_sel:BYTE_0 src1_sel:DWORD
+; GFX906-NEXT:    v_or_b32_sdwa v10, v4, v7 dst_sel:WORD_1 dst_unused:UNUSED_PAD src0_sel:BYTE_0 src1_sel:DWORD
+; GFX906-NEXT:    v_or_b32_sdwa v9, v9, v10 dst_sel:DWORD dst_unused:UNUSED_PAD src0_sel:WORD_0 src1_sel:DWORD
+; GFX906-NEXT:    v_or_b32_sdwa v10, v2, v0 dst_sel:DWORD dst_unused:UNUSED_PAD src0_sel:BYTE_0 src1_sel:DWORD
+; GFX906-NEXT:    v_or_b32_sdwa v11, v3, v5 dst_sel:WORD_1 dst_unused:UNUSED_PAD src0_sel:BYTE_0 src1_sel:DWORD
+; GFX906-NEXT:    v_mov_b32_e32 v6, 0
+; GFX906-NEXT:    v_or_b32_sdwa v10, v10, v11 dst_sel:DWORD dst_unused:UNUSED_PAD src0_sel:WORD_0 src1_sel:DWORD
+; GFX906-NEXT:    global_store_dwordx2 v6, v[9:10], s[12:13]
 ; GFX906-NEXT:  .LBB8_4: ; %bb.3
 ; GFX906-NEXT:    s_or_b64 exec, exec, s[2:3]
-; GFX906-NEXT:    v_mov_b32_e32 v0, 0
-; GFX906-NEXT:    s_waitcnt vmcnt(0)
-; GFX906-NEXT:    global_store_dwordx2 v0, v[1:2], s[14:15]
+; GFX906-NEXT:    v_or_b32_sdwa v1, v1, v8 dst_sel:DWORD dst_unused:UNUSED_PAD src0_sel:BYTE_0 src1_sel:DWORD
+; GFX906-NEXT:    v_or_b32_sdwa v4, v4, v7 dst_sel:WORD_1 dst_unused:UNUSED_PAD src0_sel:BYTE_0 src1_sel:DWORD
+; GFX906-NEXT:    v_or_b32_sdwa v0, v2, v0 dst_sel:DWORD dst_unused:UNUSED_PAD src0_sel:BYTE_0 src1_sel:DWORD
+; GFX906-NEXT:    v_or_b32_sdwa v2, v3, v5 dst_sel:WORD_1 dst_unused:UNUSED_PAD src0_sel:BYTE_0 src1_sel:DWORD
+; GFX906-NEXT:    v_mov_b32_e32 v6, 0
+; GFX906-NEXT:    v_or_b32_sdwa v1, v1, v4 dst_sel:DWORD dst_unused:UNUSED_PAD src0_sel:WORD_0 src1_sel:DWORD
+; GFX906-NEXT:    v_or_b32_sdwa v2, v0, v2 dst_sel:DWORD dst_unused:UNUSED_PAD src0_sel:WORD_0 src1_sel:DWORD
+; GFX906-NEXT:    global_store_dwordx2 v6, v[1:2], s[14:15]
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jrbyrnes wrote:

Ditto

https://github.com/llvm/llvm-project/pull/124624