[llvm] [AArch64] Add streaming-mode stack hazards. (PR #98956)

[Eli Friedman via llvm-commits]

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@@ -4537,9 +4703,15 @@ bool FrameObjectCompare(const FrameObject &A, const FrameObject &B) {
   //
   // If all else equal, sort by the object index to keep the objects in the
   // original order.
-  return std::make_tuple(!A.IsValid, A.ObjectFirst, A.GroupFirst, A.GroupIndex,
+  if (A.IsValid != B.IsValid)
+    return A.IsValid;
+  if (A.Accesses == 2 && B.Accesses != 2)
+    return true;
+  if (A.Accesses == 8 && B.Accesses != 2)
+    return true;
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efriedma-quic wrote:

Please rewrite this to something that's more obviously a strict weak ordering.

https://github.com/llvm/llvm-project/pull/98956