[llvm] [hwasan] Optimize outlined memaccess for fixed shadow on Aarch64 (PR #88544)

[Florian Mayer via llvm-commits]

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@@ -117,6 +117,7 @@ class AArch64AsmPrinter : public AsmPrinter {
   void LowerPATCHABLE_EVENT_CALL(const MachineInstr &MI, bool Typed);
 
   typedef std::tuple<unsigned, bool, uint32_t> HwasanMemaccessTuple;
+  unsigned long long HwasanFixedShadowBase = (unsigned long long)-1;
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fmayer wrote:

I would just use an optional

do i understand correctly that this is just to make sure  the offsets of all the `HWASAN_CHECK_MEMACCESS_FIXEDSHADOW_SHORTGRANULES` are the same?

https://github.com/llvm/llvm-project/pull/88544