5 Commits

Author	SHA1	Message	Date
Roman Lebedev	84c11aed10	[InstCombine] Recommit: Fold (x << y) >> y -> x & (-1 >> y) ... Summary: We already do it for splat constants, but not just values. Also, undef cases are mostly non-functional. The original commit was reverted because it broke tests for amdgpu backend, which i didn't check. Now, the backed was updated to recognize these new patterns, so we are good. https://bugs.llvm.org/show_bug.cgi?id=37603 https://rise4fun.com/Alive/cplX Reviewers: spatel, craig.topper, mareko, bogner, rampitec, nhaehnle, arsenm Reviewed By: spatel, rampitec, nhaehnle Subscribers: wdng, nhaehnle, llvm-commits Differential Revision: https://reviews.llvm.org/D47980 llvm-svn: 334818	2018-06-15 09:56:52 +00:00
Roman Lebedev	ebb3252f00	Revert rL334371 / D47980: "[InstCombine] Fold (x << y) >> y -> x & (-1 >> y)" ... test/Transforms/InstCombine/AMDGPU/amdgcn-intrinsics.ll broke, and i did not notice because i did not build that backend. llvm-svn: 334373	2018-06-10 20:32:03 +00:00
Roman Lebedev	4cdc59ecf2	[InstCombine] Fold (x << y) >> y -> x & (-1 >> y) ... Summary: We already do it for splat constants, but not just values. Also, undef cases are mostly non-functional. https://bugs.llvm.org/show_bug.cgi?id=37603 https://rise4fun.com/Alive/cplX Reviewers: spatel, craig.topper Reviewed By: spatel Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D47980 llvm-svn: 334371	2018-06-10 20:10:06 +00:00
Roman Lebedev	1e9457ee76	[NFC][InstCombine] Revisit tests for D47980 / D47981 once more. ... llvm-svn: 334370	2018-06-10 20:10:00 +00:00
Roman Lebedev	794e29f964	[NFC][InstCombine] Tests for (x << y) >> y -> x & (-1 >> y) fold. ... We already do it for splat constants, but not just values. Also, undef cases are mostly non-functional. https://bugs.llvm.org/show_bug.cgi?id=37603 https://rise4fun.com/Alive/cplX llvm-svn: 334346	2018-06-09 09:27:39 +00:00