Craig Topper 00f3579aea Revert "[InstSimplify] Remove select ?, undef, X -> X and select ?, X, undef -> X transforms" and subsequent patches ... This reverts most of the following patches due to reports of miscompiles. I've left the added test cases with comments updated to be FIXMEs. 1cf6f210a2 [IR] Disable select ? C : undef -> C fold in ConstantFoldSelectInstruction unless we know C isn't poison. 469da663f2 [InstSimplify] Re-enable select ?, undef, X -> X transform when X is provably not poison 122b0640fc [InstSimplify] Don't fold vectors of partial undef in SimplifySelectInst if the non-undef element value might produce poison ac0af12ed2 [InstSimplify] Add test cases for opportunities to fold select ?, X, undef -> X when we can prove X isn't poison 9b1e95329a [InstSimplify] Remove select ?, undef, X -> X and select ?, X, undef -> X transforms		2020-07-15 22:02:33 -07:00
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AMDGPU	Revert "[InstSimplify] Remove select ?, undef, X -> X and select ?, X, undef -> X transforms" and subsequent patches	2020-07-15 22:02:33 -07:00
NVPTX	[InferAddressSpaces] Enhance the handling of cosntexpr.	2019-05-10 14:57:42 +00:00