This code is double-dead:
1. We simplify all selects with constant true/false condition in InstSimplify.
I've minimized/moved the tests to show that works as expected.
2. All remaining vector selects with a constant condition are canonicalized to
shufflevector, so we really can't see this pattern.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312123 91177308-0d34-0410-b5e6-96231b3b80d8
This recommits r310869, with the moved files and no extra changes.
Original commit message:
This addresses a fixme in InstSimplify about using decomposeBitTest. This also fixes InstSimplify to handle ugt and ult compares too.
I've modified the interface a little to return only the APInt version of the mask that InstSimplify needs. InstCombine now has a small wrapper routine to create a Constant out of it. I've also dropped the returning of 0 since InstSimplify doesn't need that. So InstCombine creates a zero constant itself.
I also had to make decomposeBitTest support vectors since InstSimplify needs that.
As InstSimplify can't use something from the Transforms library, I've moved the CmpInstAnalysis code to the Analysis library.
Differential Revision: https://reviews.llvm.org/D36593
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310889 91177308-0d34-0410-b5e6-96231b3b80d8
Failed to add the two files that moved. And then added an extra change I didn't mean to while trying to fix that. Reverting everything.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310873 91177308-0d34-0410-b5e6-96231b3b80d8
This addresses a fixme in InstSimplify about using decomposeBitTest. This also fixes InstSimplify to handle ugt and ult compares too.
I've modified the interface a little to return only the APInt version of the mask that InstSimplify needs. InstCombine now has a small wrapper routine to create a Constant out of it. I've also dropped the returning of 0 since InstSimplify doesn't need that. So InstCombine creates a zero constant itself.
I also had to make decomposeBitTest support vectors since InstSimplify needs that.
As InstSimplify can't use something from the Transforms library, I've moved the CmpInstAnalysis code to the Analysis library.
Differential Revision: https://reviews.llvm.org/D36593
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310869 91177308-0d34-0410-b5e6-96231b3b80d8
This change caused buildbot failures, apparently because we're not
passing around types that InstSimplify is used to seeing. I'm not overly
familiar with InstSimplify, so I'm reverting this until I can figure out
what exactly is wrong.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301885 91177308-0d34-0410-b5e6-96231b3b80d8
rL245171 exposed a hole in InstSimplify that manifested in a strange way in PR28466:
https://llvm.org/bugs/show_bug.cgi?id=28466
It's possible to use trunc + icmp sgt/slt in place of an and + icmp eq/ne, so we need to
recognize that pattern to eliminate selects that are choosing between some value and some
bitmasked version of that value.
Note that there is significant room for improvement (refactoring) and enhancement (more
patterns, possibly in InstCombine rather than here).
Differential Revision: https://reviews.llvm.org/D22537
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276341 91177308-0d34-0410-b5e6-96231b3b80d8
(X & INT_MIN) ? X & INT_MAX : X into X & INT_MAX
(X & INT_MIN) ? X : X & INT_MAX into X
(X & INT_MIN) ? X | INT_MIN : X into X
(X & INT_MIN) ? X : X | INT_MIN into X | INT_MIN
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224669 91177308-0d34-0410-b5e6-96231b3b80d8
This restores our ability to optimize:
(X & C) ? X & ~C : X into X & ~C
(X & C) ? X : X & ~C into X
(X & C) ? X | C : X into X
(X & C) ? X : X | C into X | C
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222868 91177308-0d34-0410-b5e6-96231b3b80d8
