Make argsort const-correct

[AnkitAhlawat7742]

Fix: #223

Summary
argsort does not modify the input array, but its public and internal APIs previously accepted a non-const pointer. This PR makes argsort const-correct by updating the function signatures to take a const T*, improving API clarity and preventing accidental modification of input data.

Changes
Updated argsort signatures to accept const T* instead of T*

[Copilot]

Pull request overview

This PR makes the argsort function const-correct by updating its signature to accept const T* instead of T* for the input array parameter, addressing issue #223. Since argsort only reads from the input array to compute sorted indices (it doesn't modify the array), this change improves API clarity and prevents accidental modification of input data.

Changes:

• Updated argsort signature from T* to const T* across all public and internal APIs
• Updated documentation in README.md to reflect the new const-correct signature

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
lib/x86simdsort.h	Updated public API declaration of argsort to accept const T*
lib/x86simdsort.cpp	Updated DECLARE_INTERNAL_argsort macro to use const TYPE* for both function pointer and template implementation
lib/x86simdsort-skx.cpp	Updated SKX-specific argsort implementation to accept const type*
lib/x86simdsort-scalar.h	Updated scalar fallback implementation of argsort to accept const T*
lib/x86simdsort-internal.h	Updated internal API declaration of argsort to accept const T*
lib/x86simdsort-avx2.cpp	Updated AVX2-specific argsort implementation to accept const type*
README.md	Updated documentation example to show const T* in argsort signature

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[AnkitAhlawat7742]

Hi @r-devulap ,
Please re-trigger the pipeline, I have resolved the conflicts and applied the SIMD type changes.

[r-devulap]

@AnkitAhlawat7742 lint failures.

[AnkitAhlawat7742]

@AnkitAhlawat7742 lint failures.

I’ll fix it right away.

[AnkitAhlawat7742]

@r-devulap
Done...! the changes has been done to fix lint issue

[AnkitAhlawat7742]

Hi @r-devulap ,
file src/xss-common-argsort.h, caused by line-ending inconsistencies (CRLF) and template alignment.

This commit normalizes line endings and applies clang-format to that file only, so that the repository now passes the CI formatting check cleanly.

No functional or logic changes are introduced.
Please trigger the CI CD pipeline

[AnkitAhlawat7742]

@r-devulap — is it possible the CI is still running an older job?

I verified the formatting locally on the current branch head using:

find . -type f \( -name "*.c" -o -name "*.cpp" -o -name "*.h" -o -name "*.hpp" \) \
  -print0 | xargs -0 clang-format -style=file --dry-run -Werror
(py313_env) ankitahlawat@AnkitAhlawats-MacBook-Pro x86-simd-sort % git status
On branch fix/argsort-const-correctness
Your branch is up to date with 'origin/fix/argsort-const-correctness'.

nothing to commit, working tree clean

The working tree is clean and the branch fix/argsort-const-correctness is fully in sync with origin.

[r-devulap]

I am using: Ubuntu clang-format version 18.1.3 (1ubuntu1) anmd the command I use:

clang-format -i -style=file lib/*.h

[AnkitAhlawat7742]

I am using: Ubuntu clang-format version 18.1.3 (1ubuntu1) anmd the command I use:

clang-format -i -style=file lib/*.h

Got it, thanks for pointing this out.

The earlier failures were due to formatting differences between macOS clang-format (v21) and the CI environment.
I’ve now verified and applied formatting using the same toolchain as CI (Ubuntu clang-format 18.1.3).
The current commit reflects the clang-format-18 output and matches the CI check exactly.

This should now pass the CI formatting step.

[AnkitAhlawat7742]

I am using: Ubuntu clang-format version 18.1.3 (1ubuntu1) anmd the command I use:

clang-format -i -style=file lib/*.h

Hey @r-devulap ,

Got it, thanks for pointing this out.

The earlier failures were due to formatting differences between macOS clang-format (v21) and the CI environment. I’ve now verified and applied formatting using the same toolchain as CI (Ubuntu clang-format 18.1.3). The current commit reflects the clang-format-18 output and matches the CI check exactly.

This should now pass the CI formatting step.

[Copilot]

Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated no new comments.

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[r-devulap]

LGTM. Do you want to update the argselect method as well? Might be good to complete that change in one patch.

[AnkitAhlawat7742]

LGTM. Do you want to update the argselect method as well? Might be good to complete that change in one patch.

Thanks @r-devulap
To keep this PR scoped, I’ll address argselect in a follow-up PR and will raise it shortly.