[clang] [llvm] [AArch64] Enable the new SME ABI lowering (`-aarch64-new-sme-abi`) by default (PR #172642)

[Sander de Smalen via llvm-commits]

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@@ -10,653 +10,337 @@ declare void @llvm.trap() #0
 
 define void @quux() #1 {
 ; CHECK-LABEL: quux:
-; CHECK:       // %bb.0: // %prelude
-; CHECK-NEXT:    stp x29, x30, [sp, #-96]! // 16-byte Folded Spill
-; CHECK-NEXT:    stp x28, x27, [sp, #16] // 16-byte Folded Spill
-; CHECK-NEXT:    stp x26, x25, [sp, #32] // 16-byte Folded Spill
-; CHECK-NEXT:    stp x24, x23, [sp, #48] // 16-byte Folded Spill
-; CHECK-NEXT:    stp x22, x21, [sp, #64] // 16-byte Folded Spill
-; CHECK-NEXT:    stp x20, x19, [sp, #80] // 16-byte Folded Spill
-; CHECK-NEXT:    mov x29, sp
-; CHECK-NEXT:    sub sp, sp, #384
-; CHECK-NEXT:    .cfi_def_cfa w29, 96
-; CHECK-NEXT:    .cfi_offset w19, -8
-; CHECK-NEXT:    .cfi_offset w20, -16
-; CHECK-NEXT:    .cfi_offset w21, -24
-; CHECK-NEXT:    .cfi_offset w22, -32
-; CHECK-NEXT:    .cfi_offset w23, -40
-; CHECK-NEXT:    .cfi_offset w24, -48
-; CHECK-NEXT:    .cfi_offset w25, -56
-; CHECK-NEXT:    .cfi_offset w26, -64
-; CHECK-NEXT:    .cfi_offset w27, -72
-; CHECK-NEXT:    .cfi_offset w28, -80
-; CHECK-NEXT:    .cfi_offset w30, -88
-; CHECK-NEXT:    .cfi_offset w29, -96
-; CHECK-NEXT:    rdsvl x8, #1
+; CHECK:       // %bb.0: // %bb
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sdesmalen-arm wrote:

I would argue this test has outlived its usefulness, because it was already no longer testing that x19 would be used since 15fbdc2b9635b75f431a26b89b48fe03e7ed9d5c. I suggest removing this test entirely.

https://github.com/llvm/llvm-project/pull/172642