[PATCH] D87371: [MC] [Win64EH] Try to generate packed unwind info where possible

[Martin Storsjö via Phabricator via llvm-commits]

mstorsjo added inline comments.


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Comment at: llvm/lib/MC/MCWin64EH.cpp:717
+      // RegI=10/RegF=8/CR=1/H=1, we end up with SavSZ = 216, which should
+      // fit into SaveR19R20X.
+      // The unwinding opcodes can't describe the otherwise seemingly valid
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After updating the other patch, where a "stp x19, x20" can't be made into SaveR19R20X if the offset is too large, I tried update the code here to expect SaveRegPX for x19 - but it turns out it's impossible to make such a case with a large enough offset not to be canonicalized into SaveR19R20X, while maintaining the expected stack layout here, so I just updated the comment here.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D87371/new/

https://reviews.llvm.org/D87371