[PATCH] D159186: [AArch64][SME] Enable TPIDR2 lazy-save for za_preserved

[Sander de Smalen via Phabricator via llvm-commits]

sdesmalen added inline comments.


================
Comment at: llvm/lib/Target/AArch64/AArch64ISelLowering.cpp:7309
+  else if (auto *ES = dyn_cast<ExternalSymbolSDNode>(CLI.Callee))
+    if (auto SMEABIAttrs = SMEAttrs(ES->getSymbol()))
+      CalleeAttrs = SMEABIAttrs;
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Do we really need the `if`-statement? For example, can we just write:

  else if (auto *ES = ...)
    CalleeAttrs = SMEAttrs(ES->getSymbol());

If the default for `SMEAttrs(<symbol>)` is that it doesn't have any streaming- or ZA properties then this is equivalent to what we had before this patch



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Comment at: llvm/lib/Target/AArch64/Utils/AArch64SMEAttributes.cpp:26
   assert(!(hasNewZABody() && preservesZA()) &&
          "ZA_New and ZA_Preserved are mutually exclusive");
 }
----------------
Does this need a new assert to say that NewZA and SharedZA cannot be combined with `NoLazySave`?


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Comment at: llvm/lib/Target/AArch64/Utils/AArch64SMEAttributes.h:90
+
+  operator bool() { return Bitmask; }
 };
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I'd rather we don't add an `operator bool()`, because it's not clear to me what it is supposed to represent that the existing interfaces don't represent already.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D159186/new/

https://reviews.llvm.org/D159186