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Missing Bit Manipulation Instruction Sets: ABM, BMI1, BMI2, and TBM #21

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xelxebar opened this issue Feb 13, 2022 · 4 comments
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Missing Bit Manipulation Instruction Sets: ABM, BMI1, BMI2, and TBM #21

xelxebar opened this issue Feb 13, 2022 · 4 comments
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missing instruction vex

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@xelxebar
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Just recently having learned about the various Bit Manipulation Instruction Sets, I happened to notice their conspicuous lack on the x86reference. Is this intentional for some reason, or would it be worth a PR?
@BarebitOpenSource
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POPCNT is already there. LZCNT should be added.

BMI1, BMI2, and TBM are VEX-ecoded instructions and VEX encoding is yet to be implemented.

@BarebitOpenSource
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TZCNT — Count the Number of Trailing Zero Bits

F3 0F BC /r       TZCNT r16, r/m16
F3 0F BC /r       TZCNT r32, r/m32
F3 REX.W 0F BC /r TZCNT r64, r/m64

TZCNT Gv, Ev

CPU feature: BMI1

@BarebitOpenSource
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Added LZCNT that is not part of BMI1.

@BarebitOpenSource
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Added TZCNT. It's part of BMI1 but the only non-VEX instruction. The rest of the BMI instructions will be added along with all the other VEX instructons.

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@xelxebar @BarebitOpenSource