Update conv get-plan sample heuristic config count

[yeliu-oss]

Summary by CodeRabbit

• Refactor
  • Restructured the internal configuration generation logic for improved code maintainability.
  • Updated the configuration retrieval mechanism to request a more limited set of plans, potentially improving performance and reducing memory overhead.

[coderabbitai]

📝 Walkthrough

Walkthrough

This PR refactors the cuDNN heuristics engine configuration generator in conv_sample.cpp by extracting a shared helper function, creating two method variants for controlling the number of configs selected, and updating the generator to use the single-config variant.

Changes

Heuristics engine config selection refactoring

Layer / File(s)	Summary
Heuristics config helper extraction and variant methods samples/legacy_samples/conv_sample.cpp	Extracts shared get_engine_configs_from_heuristics helper with configurable max config count. Refactors heurgen_method to call the helper with unlimited count; adds heurgen_method_first_config for single-config selection. Updates run_from_cudnn_get to use heurgen_method_first_config, changing the plan retrieval behavior.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Poem

🐰 A refactor swift, a helper born,
Two methods split from config worn,
First one shines through the generator's call,
While shared code handles them all!

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main change: refactoring the heuristic engine config count behavior in the conv sample by adding a new method to request only the first configuration.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

Warning

There were issues while running some tools. Please review the errors and either fix the tool's configuration or disable the tool if it's a critical failure.

🔧 Infer (1.2.0)

samples/legacy_samples/conv_sample.cpp

In file included from samples/legacy_samples/conv_sample.cpp:23:
samples/legacy_samples/conv_sample.h:30:10: fatal error: 'cuda_runtime.h' file not found
30 | #include <cuda_runtime.h>
| ^~~~~~~~~~~~~~~~
1 error generated.
samples/legacy_samples/conv_sample.cpp:230:120-248:1: ERROR translating statement 'CompoundStmt'
Aborting translation of method 'create_operation_graph' in file 'samples/legacy_samples/conv_sample.cpp': "Assert_failure src/clang/cAst_utils.ml:249:53"
Uncaught Internal Error: "Assert_failure src/clang/cAst_utils.ml:249:53"
Error backtrace:
Raised at ClangFrontend__CAst_utils.get_decl_from_typ_ptr in file "src/clang/cAst_utils.ml", line 249, characters 53-65
Called from ClangFrontend__CTrans.CTrans_funct.get_destructor_decl_ref in file "src/clang/cTrans.ml", line 658, characters 12-59
Called from ClangFrontend__CTrans.CTrans_funct.destructor_calls.(fun) in file "src/clang/cTrans.ml", line 2048, characters 12-69
Called from Base__List.rev_filter_map.lo

... [truncated 2200 characters] ...

ntend__CFrontend_decl.CFrontend_decl_funct.add_method in file "src/clang/cFrontend_decl.ml" (inlined), line 54, characters 4-52
Called from ClangFrontend__CFrontend_decl.CFrontend_decl_funct.function_decl in file "src/clang/cFrontend_decl.ml", line 90, characters 12-151
Called from ClangFrontend__CFrontend_decl.CFrontend_decl_funct.translate_one_declaration in file "src/clang/cFrontend_decl.ml", line 453, characters 10-56
Called from Stdlib__List.iter in file "list.ml", line 110, characters 12-15
Called from Stdlib__List.iter in file "list.ml" (inlined), line 110, characters 17-25
Called from Base__List0.iter in file "src/list0.ml" (inlined), line 25, characters 16-35
Called from ClangFrontend__CFrontend.compute_icfg in file "src/clang/cFrontend.ml", line 28, characters 6-130
Called from C

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[coderabbitai]

🧹 Nitpick comments (1)

samples/legacy_samples/conv_sample.cpp (1)

983-983: ⚡ Quick win

Document the rationale for requesting only the first config.

Changing from heurgen_method (all configs) to heurgen_method_first_config (1 config) significantly alters behavior:

• Only one plan will be available for execution
• Workspace size calculation (lines 989-995) will only consider the first plan
• No fallback plans if the first config fails to build or execute

While this aligns with using cudnnGetPlan for heuristics-only workflows (per comment lines 1011-1013), adding a comment here would clarify that a single top-heuristic config is sufficient for this use case.

📝 Suggested comment

+        // Use first config only since cudnnGetPlan is for heuristics-based plan selection without benchmarking
         std::array<cudnn_frontend::GeneratorSource const, 1> sources = {heurgen_method_first_config};

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@samples/legacy_samples/conv_sample.cpp` at line 983, Assigning only the top
heuristic config via heurgen_method_first_config (instead of heurgen_method)
intentionally restricts execution to a single plan: add a comment at the sources
assignment explaining this choice, referencing heurgen_method_first_config and
cudnnGetPlan so readers know we only need the top heuristic for a
heuristics-only workflow; note the implications that workspace size computation
and plan-building will consider only that first config and there will be no
fallback plans if it fails, and justify that this is acceptable because the code
is using cudnnGetPlan-style heuristics rather than enumerating all configs.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@samples/legacy_samples/conv_sample.cpp`:
- Line 983: Assigning only the top heuristic config via
heurgen_method_first_config (instead of heurgen_method) intentionally restricts
execution to a single plan: add a comment at the sources assignment explaining
this choice, referencing heurgen_method_first_config and cudnnGetPlan so readers
know we only need the top heuristic for a heuristics-only workflow; note the
implications that workspace size computation and plan-building will consider
only that first config and there will be no fallback plans if it fails, and
justify that this is acceptable because the code is using cudnnGetPlan-style
heuristics rather than enumerating all configs.

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ℹ️ Review info

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📥 Commits

Reviewing files that changed from the base of the PR and between 1a2799b and ff4276d.

📒 Files selected for processing (1)

• samples/legacy_samples/conv_sample.cpp