[llvm] [AArch64] Implement assembler support for new SVE SEH unwind opcodes. (PR #137895)

[Martin Storsjö via llvm-commits]

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@@ -1004,6 +1040,9 @@ static bool tryARM64PackedUnwind(WinEH::FrameInfo *info, uint32_t FuncLength,
     case Win64EH::UOP_SaveAnyRegDPX:
     case Win64EH::UOP_SaveAnyRegQX:
     case Win64EH::UOP_SaveAnyRegQPX:
+    case Win64EH::UOP_AllocZ:
+    case Win64EH::UOP_SaveZReg:
+    case Win64EH::UOP_SavePReg:
       // These are never canonical; they don't show up with the usual Arm64
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mstorsjo wrote:

This comment feels a little bit misplaced with respect to these new opcodes; they don't match a packed prologue of course, but they can show up with the usual arm64 calling conventions.

https://github.com/llvm/llvm-project/pull/137895