[PATCH] D97853: [AVR] Do not chain stores in call frame setup

[Ayke via Phabricator via llvm-commits]

aykevl created this revision.
aykevl added reviewers: dylanmckay, benshi001.
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Previously, `AVRTargetLowering::LowerCall` attempted to keep stack stores in order with chains. Perhaps this worked in the past, but it does not work now: it appears that the SelectionDAG legalization phase removes these chains. Therefore, I've removed these chains entirely to match X86 (which, similar to AVR, also prefers to use push instructions over stack-relative stores to set up a call frame). With this change, all the stack stores are in a somewhat reasonable order.

See also: https://reviews.llvm.org/D78581.

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I ran my batch of compiler-rt tests locally and they still pass with this patch.
This patch is really a preparation for a different patch that attempts to optimize/fix the bug I originally tried to fix in D78581 <https://reviews.llvm.org/D78581> but didn't do correctly.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D97853

Files:
  llvm/lib/Target/AVR/AVRISelLowering.cpp
  llvm/test/CodeGen/AVR/call.ll
  llvm/test/CodeGen/AVR/dynalloca.ll
  llvm/test/CodeGen/AVR/varargs.ll

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