[WIP][DAG] combineVSelectWithAllOnesOrZeros - fold "select Cond, 0, x -> and not(Cond), x" #146831
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… -> and not(Cond), x" Extend llvm#145298 to remove the x86 combineVSelectWithLastZeros special case WIP - still a couple of x86 regressions to address wrt unnecessary duplicated comparisons Fixes llvm#144513
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…d not(Cond), x (#147472) ### Summary This patch extends the work from [#145298](#145298) by removing the now-unnecessary X86-specific combineVSelectWithLastZeros logic. That combine is now correctly and more generally handled in the target-independent combineVSelectWithAllOnesOrZeros. This simplifies the X86 DAG combine logic and avoids duplication. Fixes: [#144513](#144513) Related for reference: [#146831](#146831)
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… 0, x -> and not(Cond), x (#147472) ### Summary This patch extends the work from [#145298](llvm/llvm-project#145298) by removing the now-unnecessary X86-specific combineVSelectWithLastZeros logic. That combine is now correctly and more generally handled in the target-independent combineVSelectWithAllOnesOrZeros. This simplifies the X86 DAG combine logic and avoids duplication. Fixes: [#144513](llvm/llvm-project#144513) Related for reference: [#146831](llvm/llvm-project#146831)
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Extend #145298 to remove the x86 combineVSelectWithLastZeros special case
WIP - still a couple of x86 regressions to address wrt unnecessary duplicated comparisons
Fixes #144513