[compiler-rt] [AArch64][SME] Rewrite __arm_get_current_vg to preserve required registers (PR #100143)

[Sander de Smalen via llvm-commits]

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@@ -28,22 +28,3 @@ __attribute__((constructor(90))) static void get_aarch64_cpu_features(void) {
 
   __init_cpu_features();
 }
-
-__attribute__((target("sve"))) long
-__arm_get_current_vg(void) __arm_streaming_compatible {
-  struct SME_STATE State = __arm_sme_state();
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sdesmalen-arm wrote:

Can the definition of this struct and the prototype of `__arm_sme_state` be removed as well?

https://github.com/llvm/llvm-project/pull/100143