[llvm] GlobalISel: adapt MachineSSAUpdater for use in GlobalISel path (PR #78431)

[Matt Arsenault via llvm-commits]

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@@ -66,15 +65,16 @@ exit:
 define amdgpu_ps void @divergent_i1_phi_uniform_branch_simple(ptr addrspace(1) %out, i32 %tid, i32 inreg %cond) {
 ; GFX10-LABEL: divergent_i1_phi_uniform_branch_simple:
 ; GFX10:       ; %bb.0: ; %A
+; GFX10-NEXT:    v_cmp_le_u32_e64 s1, 6, v2
 ; GFX10-NEXT:    s_cmp_lg_u32 s0, 0
-; GFX10-NEXT:    s_cbranch_scc0 .LBB1_2
-; GFX10-NEXT:  ; %bb.1:
-; GFX10-NEXT:    v_cmp_le_u32_e64 s0, 6, v2
-; GFX10-NEXT:    s_branch .LBB1_3
-; GFX10-NEXT:  .LBB1_2: ; %B
-; GFX10-NEXT:    v_cmp_gt_u32_e64 s0, 1, v2
-; GFX10-NEXT:  .LBB1_3: ; %exit
-; GFX10-NEXT:    v_cndmask_b32_e64 v2, 0, -1, s0
+; GFX10-NEXT:    s_cbranch_scc1 .LBB1_2
+; GFX10-NEXT:  ; %bb.1: ; %B
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arsenm wrote:

code changes seem incidental from not running the test before?

https://github.com/llvm/llvm-project/pull/78431