[PATCH] D74787: [IRBuilder] Always respect inserter/folder

Tue Feb 18 13:31:04 PST 2020

nikic marked an inline comment as done.
nikic added inline comments.

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Comment at: llvm/test/Transforms/InstCombine/saturating-add-sub.ll:2
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -instcombine -S | FileCheck %s
+; RUN: opt < %s -instcombine -instcombine-infinite-loop-threshold=2 -S | FileCheck %s

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Meinersbur wrote:
> IMHO how the folding works internally (folded by IRBuilder instead of InstCombine rule) does not need to be part of a/this regression test. If another test is added to this file requiring 3 rounds, it would raise some confusions.
To clarify, "iterations" here is how often InstCombine runs (with a full instruction scan), not how many instructions each run visits. There should be at most two iterations, one to perform folds and one to verify the fixpoint. If there are more iterations, that's a bug in worklist management. I'm currently tracking down all these bugs and annotating tests with `-instcombine-infinite-loop-threshold=2` to verify that the issue is indeed fixed.

Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D74787/new/

https://reviews.llvm.org/D74787