[PATCH] D61282: [InlineCost] Check if caller formulates indirect recursion.

[Taewook Oh via Phabricator via llvm-commits]

twoh created this revision.
twoh added reviewers: david2050, modocache, eraman, nadav, rnk.
Herald added subscribers: dexonsmith, haicheng, hiraditya, mehdi_amini.
Herald added a project: LLVM.

If a function uses stack heavily, the function shouldn't be inlined if the
caller can be recursively invoked, because it may lead stack size explosion.
Current inliner implemention only checks for self-recursion, but indirectely
recursive function has the same risk, and that actually happens with MySQL5.6+LTO.

To overcome this limitation, this diff adds a knob that can control the
"degree" of indirect recursion that the inliner attempts to detect. The default
value is 1 which means that it only checks for self-recursion, and wouldn't
change the current behavior.. MySQL issue can be addressed by setting the flag
to 2.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D61282

Files:
  llvm/lib/Analysis/InlineCost.cpp
  llvm/test/Transforms/Inline/recursive.ll

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