Delete cuTensor

[wilfonba]

User description

Description

Delete cuTensor and the code for riemann_flat and weno_flat that hasn't existed for years.

Type of change

• Something else

Scope

• This PR comprises a set of related changes with a common goal

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PR Type

Other

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Description

• Remove cuTensor library support from MFC

• Delete compiler checks for cuTensor availability

• Remove cuTensor-based tensor reshaping operations

• Simplify WENO scheme to use standard GPU loops

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Diagram Walkthrough

flowchart LR
  A["cuTensor Support"] -- "remove" --> B["Standard GPU Loops"]
  C["CMake Configuration"] -- "delete" --> D["Simplified Build"]
  E["Compiler Checks"] -- "remove" --> F["Cleaner Validation"]

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File Walkthrough

	Relevant files
Configuration changes	m_checker.fpp Remove cuTensor compiler validation                                            src/simulation/m_checker.fpp Remove compiler check for cuTensor library availability Delete MFC_cuTENSOR preprocessor condition +0/-5
Enhancement	m_weno.fpp Replace cuTensor with standard GPU loops                                  src/simulation/m_weno.fpp Remove cuTensor-based tensor reshaping operations Replace with standard GPU parallel loops Simplify WENO characteristic field projections Delete cuTensorEx module usage +15/-52
Dependencies	CMakeLists.txt Remove cuTensor build configuration                                            CMakeLists.txt Remove cuTensor package finding logic Delete cuTensor library linking Remove MFC_cuTENSOR compile definition +0/-11

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[Copilot]

Pull Request Overview

This PR removes cuTensor support from MFC by eliminating all cuTensor-related code, build configurations, and conditional compilation blocks. The changes simplify the WENO implementation by removing GPU-accelerated tensor reshape operations and their associated fallback logic.

Key changes:

• Removal of cuTensor conditional compilation blocks and reshape operations in WENO routines
• Elimination of cuTensor build system integration and compiler checks
• Simplification of control flow by removing cuTensor-specific code paths

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/simulation/m_weno.fpp	Removes cuTensor conditional blocks and GPU tensor reshape operations for y and z directions
src/simulation/m_checker.fpp	Eliminates cuTensor compiler availability check
CMakeLists.txt	Removes cuTensor library detection, linking, and build configuration

Comments suppressed due to low confidence (1)

src/simulation/m_weno.fpp:1165

• [nitpick] This appears to be an unintentional blank line addition. Consider removing it to maintain consistent spacing in the code.

                        do k = is1_weno%beg - weno_polyn, is1_weno%end + weno_polyn

[qodo-code-review]

PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

⏱️ Estimated effort to review: 2 🔵🔵⚪⚪⚪

🧪 No relevant tests

🔒 No security concerns identified

⚡ Recommended focus areas for review Logic Change The removal of cuTensor conditional logic may change computational behavior. The standard GPU loops replace tensor reshaping operations which could have different performance characteristics or numerical precision. Verify that the replacement logic produces equivalent results. $:GPU_PARALLEL_LOOP(collapse=4) do j = 1, v_size do q = is3_weno%beg, is3_weno%end do l = is2_weno%beg, is2_weno%end do k = is1_weno%beg - weno_polyn, is1_weno%end + weno_polyn v_rs_ws_y(k, l, q, j) = v_vf(j)%sf(l, k, q) end do end do end do end do end if ! Reshaping/Projecting onto Characteristic Fields in z-direction if (p == 0) return if (weno_dir == 3) then $:GPU_PARALLEL_LOOP(collapse=4) do j = 1, v_size do q = is3_weno%beg, is3_weno%end do l = is2_weno%beg, is2_weno%end do k = is1_weno%beg - weno_polyn, is1_weno%end + weno_polyn v_rs_ws_z(k, l, q, j) = v_vf(j)%sf(q, l, k) end do end do end do end do end if Missing Validation The removal of the cu_tensor parameter validation check means users can still set cu_tensor=T but it will no longer be validated or functional. This could lead to silent failures or unexpected behavior. impure subroutine s_check_inputs_compilers #if !defined(MFC_OpenACC) && !(defined(__PGI) || defined(_CRAYFTN)) @:PROHIBIT(rdma_mpi, "Unsupported value of rdma_mpi for the current compiler") #endif end subroutine s_check_inputs_compilers

[qodo-code-review]

PR Code Suggestions ✨

No code suggestions found for the PR.

[sbryngelson]

a couple of stragglers?

https://github.com/search?q=repo%3Awilfonba%2FMFC-Wilfong+cutensor+OR+repo%3Awilfonba%2FMFC-Wilfong++cu_tensor&type=code

[wilfonba]

a couple of stragglers?

github.com/search?q=repo%3Awilfonba%2FMFC-Wilfong+cutensor+OR+repo%3Awilfonba%2FMFC-Wilfong++cu_tensor&type=code

I think this is a search of the master branch on my fork? These are all of the lines that I removed.

[sbryngelson]

nvm. will merge when tests pass (which i'm sure they will)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 44.06%. Comparing base (f2ef560) to head (58dcc9b).
Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #965      +/-   ##
==========================================
- Coverage   44.08%   44.06%   -0.02%     
==========================================
  Files          69       69              
  Lines       19573    19568       -5     
  Branches     2428     2430       +2     
==========================================
- Hits         8628     8623       -5     
  Misses       9444     9444              
  Partials     1501     1501              

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