[PATCH] D109104: [CSSPGO] Allow inlining recursive call for preinliner

Thu Sep 2 09:15:42 PDT 2021

hoy added inline comments.

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Comment at: llvm/lib/Transforms/IPO/SampleProfile.cpp:1290
+  // TODO: Evaluate if this is helpful for AutoFDO too in general.
+  Params.AllowRecursiveCall = ProfileIsCS && UsePreInlinerDecision;
   // Checks if there is anything in the reachable portion of the callee at
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wenlei wrote:
> hoy wrote:
> > Should this also be enabled for csspgo without preliner?
> Hmm.. actually this is what it currently does. UsePreInlinerDecision is on by default for CSSPGO. So basically, we have `sample-profile-use-preinliner` indirectly controls whether we allow recursive inline. Do you think we should have separate switch just for recursive inlining? That probably makes experimenting with AutoFDO a bit easier too.
Oh yeah, `UsePreInlinerDecision` is on by default for CSSPGO. A separate switch would be more solid like the decision won't be changed when `UsePreInlinerDecision` is off. It is also handy for experimenting with AutoFDO.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D109104/new/

https://reviews.llvm.org/D109104