Change Status flags in EFLAGS(ZF)

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#1,287 3 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
25/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
rust
Domain
backend

Research direction

Start by examining the asm! entry point and the _mm512_kortestc intrinsic described in the issue. Check current nightly support for changing status flags and determine whether the requested ZF behavior is supported; done means answering that feasibility question with the relevant limitation or support status.

Written by the indexing model from the issue text.

Description

Is it possible to change ZF flag using asm!?

For intrinsics _mm512_kortestc:

Description
Performs bitwise OR between k1 and k2, storing the result in dst. CF flag is set if dst consists of all 1's.

Operation
dst[15:0] := k1[15:0] | k2[15:0]
IF PopCount(dst[15:0]) == 16
SetCF()
FI

Is this doable in the nightly version?

Dominant language
Rust
Stars
694
Forks
336
Avg merge
5d 14h
Merged PRs (30d)
9

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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