[PATCH] D44102: Teach CorrelatedValuePropagation to reduce the width of udiv/urem instructions.

Justin Lebar via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Wed Mar 7 09:03:53 PST 2018


jlebar added a comment.

Pushed the fix, https://reviews.llvm.org/rL326908.  It was indeed something simple: Given e.g. udiv i24 with no constraints on the operands, we noticed that the smallest power of 2 that could contain the operands was i32, and then tried to *expand* the udiv.  Which is wrong, and also blew up because we were trying to trunc from i24 -> i32 and zext from i32 -> i24.


Repository:
  rL LLVM

https://reviews.llvm.org/D44102





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