David Majnemer dfe81adbce InstCombine: Don't miscompile (x lshr C1) udiv C2 ...

We have a transform that changes:
  (x lshr C1) udiv C2
into:
  x udiv (C2 << C1)

However, it is unsafe to do so if C2 << C1 discards any of C2's bits.

This fixes PR21255.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219634 91177308-0d34-0410-b5e6-96231b3b80d8

2014-10-13 21:48:30 +00:00

66 KiB

Raw Blame History

View Raw