[llvm] [AArch64][SME] Support `aarch64-split-sve-objects` with VLAs/realignment (PR #163816)

[Benjamin Maxwell via llvm-commits]

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@@ -3512,14 +3512,13 @@ define i32 @svecc_call_dynamic_alloca(<4 x i16> %P0, i32 %P1, i32 %P2, <vscale x
 ;
 ; CHECK64-LABEL: svecc_call_dynamic_alloca:
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MacDue wrote:

Quite a lot of churn here, not really sure how helpful these tests are... I've created smaller test cases in `split-sve-stack-frame-layout.ll` that should be easier to follow. 

https://github.com/llvm/llvm-project/pull/163816