tree db864ab301ea6d025d9cec40706b2b28831c3f10
parent b98d8ca15ff81418e0ab5c2ee5310f392f07c3ec
author Craig Topper <craig.topper@intel.com> 1552547246 +0000
committer Craig Topper <craig.topper@intel.com> 1552547246 +0000

[X86] Add patterns for rotr by immediate to fix PR41057.

Prior to the introduction of funnel shift intrinsics we could count on rotate
by immediates prefering to use rotl since that's what MatchRotate would check
first. The or+shift pattern doesn't have a direction so one must be chosen
arbitrarily.

With funnel shift, there is a direction and fshr will try to use rotr first.
While fshl will try to use rotl first.

This patch adds the isel patterns for rotr to complement the rotl patterns. I've
put the rotr by 1 patterns in the instruction patterns. And moved the rotl by
bitwidth-1 patterns to separate Pat patterns.

Fixes PR41057.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356121 91177308-0d34-0410-b5e6-96231b3b80d8