[llvm] [AArch64][SME] Propagate desired ZA states in the MachineSMEABIPass (PR #149510)

[Benjamin Maxwell via llvm-commits]

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@@ -923,23 +892,27 @@ define void @loop_with_external_entry(i1 %c1, i1 %c2) "aarch64_inout_za" nounwin
 ; CHECK-NEWLOWERING-NEXT:  // %bb.1: // %init
 ; CHECK-NEWLOWERING-NEXT:    bl shared_za_call
 ; CHECK-NEWLOWERING-NEXT:  .LBB11_2: // %loop.preheader
-; CHECK-NEWLOWERING-NEXT:    sub x8, x29, #16
-; CHECK-NEWLOWERING-NEXT:    msr TPIDR2_EL0, x8
+; CHECK-NEWLOWERING-NEXT:    sub x20, x29, #16
+; CHECK-NEWLOWERING-NEXT:    b .LBB11_4
 ; CHECK-NEWLOWERING-NEXT:  .LBB11_3: // %loop
+; CHECK-NEWLOWERING-NEXT:    // in Loop: Header=BB11_4 Depth=1
+; CHECK-NEWLOWERING-NEXT:    msr TPIDR2_EL0, xzr
+; CHECK-NEWLOWERING-NEXT:    tbz w19, #0, .LBB11_6
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MacDue wrote:

Note: This regression is fixed by #149065

https://github.com/llvm/llvm-project/pull/149510