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iasm, lzcnt and tznct are not recognized
Feb 25, 2020
Basile B.
Feb 26, 2020
kinke
Feb 26, 2020
Basile B.
February 25, 2020
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Basile B.
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lzcnt and tznct are not recognized.
DMD accept them.
February 26, 2020
Gravatar of kinkePosted by kinke
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On Tuesday, 25 February 2020 at 21:18:48 UTC, Basile B. wrote:
> lzcnt and tznct are not recognized.
> DMD accept them.

I guess you mean in DMD-style inline asm; that part doesn't see much love. LDC-style __asm provides all of them, at least as long as using appropriate -mcpu/-mattr switches.

Looks like you're trying to manually optimize bsf/bsr; I'd advise against that, standard core.bitop generates exactly these 2 instructions: https://d.godbolt.org/z/PG8GiU
February 26, 2020
Gravatar of Basile B.Posted by Basile B.
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Basile B.
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On Wednesday, 26 February 2020 at 03:07:22 UTC, kinke wrote:
> On Tuesday, 25 February 2020 at 21:18:48 UTC, Basile B. wrote:
>> lzcnt and tznct are not recognized.
>> DMD accept them.
>
> I guess you mean in DMD-style inline asm; that part doesn't see much love. LDC-style __asm provides all of them, at least as long as using appropriate -mcpu/-mattr switches.
>
> Looks like you're trying to manually optimize bsf/bsr; I'd advise against that, standard core.bitop generates exactly these 2 instructions: https://d.godbolt.org/z/PG8GiU

indeed -mcpu solves the problem.