4 Commits

Author	SHA1	Message	Date
Sanjay Patel	8253e15ef3	[DAG] add fold for masked negated sign-extended bool ... This enhances the fold added with: https://reviews.llvm.org/rL283900 llvm-svn: 283905	2016-10-11 17:05:52 +00:00
Sanjay Patel	58b4987284	[x86] add sext variants of tests added with r283894 ... llvm-svn: 283903	2016-10-11 16:49:52 +00:00
Sanjay Patel	8384703d9b	[DAG] add fold for masked negated extended bool ... The non-obvious motivation for adding this fold (which already happens in InstCombine) is that we want to canonicalize IR towards select instructions and canonicalize DAG nodes towards boolean math. So we need to recreate some folds in the DAG to handle that change in direction. An interesting implementation difference for cases like this is that InstCombine generally works top-down while the DAG goes bottom-up. That means we need to detect different patterns. In this case, the SimplifyDemandedBits fold prevents us from performing a zext to sext fold that would then be recognized as a negation of a sext. llvm-svn: 283900	2016-10-11 16:26:36 +00:00
Sanjay Patel	9b3c8a7321	[x86] add tests to show missed folds for masked bools ... llvm-svn: 283894	2016-10-11 16:04:37 +00:00