[llvm-dev] CTPOP and zeroes

ORiordan, Martin via llvm-dev llvm-dev at lists.llvm.org
Thu Jan 18 00:57:40 PST 2018

Quick question.  The 'ISD::CTPOP' node allows a target to lower the counting of ones in a word to a single instruction.  Our target also has an instruction for counting the zeroes in a word.  Does CTPOP support counting of zeroes as well as ones instead of doing either "CTPOP(INVERT(operand))" or "N-bits - CTPOP(operand)"?



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