[llvm] [AArch64][SME] Implement the SME ABI (ZA state management) in Machine IR (PR #149062)

[Paul Walker via llvm-commits]

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@@ -812,6 +824,9 @@ bool AArch64PassConfig::addILPOpts() {
 }
 
 void AArch64PassConfig::addPreRegAlloc() {
+  if (EnableNewSMEABILowering && TM->getOptLevel() == CodeGenOptLevel::None)
+    addPass(createMachineSMEABIPass());
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paulwalker-arm wrote:

Petty I know but all the existing code is structured `TM->getOptLevel() == CodeGenOptLevel::None && ...` and I see no reason to deviate.

https://github.com/llvm/llvm-project/pull/149062