Minor cleanup to Communicator

[wujingyue]

No description provided.

[wujingyue]

!test

[github-actions]

Description

• Standardized null pointer checks to use explicit == nullptr comparison

• Simplified device index initialization logic for consistency

• Removed unused "exceptions.h" include from communicator header

• Improved code readability through consistent coding style

Changes walkthrough

Relevant files

Enhancement

evaluator.cpp Standardized null pointer checks and simplified logic        csrc/host_ir/evaluator.cpp Changed null pointer check from communicator_ ? to communicator_ == nullptr ? Simplified device_index initialization to use consistent null check pattern Maintained same functionality while improving code consistency +3/-4      communicator.h Removed unused exceptions.h include                                            csrc/multidevice/communicator.h Removed unused include of "exceptions.h" header file Cleaned up header dependencies to reduce compilation overhead +0/-1

PR Reviewer Guide

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🧪 No relevant tests

🔒 No security concerns identified

⚡ Recommended focus areas for review

Functional Logic Change The device index calculation logic has been changed from checking both 'communicator_ != nullptr && communicator_->is_available()' to only checking 'communicator_ == nullptr'. This removes the 'is_available()' check which could be a functional change if the communicator can exist but not be available. Need to verify this doesn't break existing functionality. const DeviceIdxType device_index = communicator_ == nullptr ? 0 : communicator_->deviceId(); if (isDebugDumpEnabled(DebugDumpOption::HostIr) && device_index == 0) {

[greptile-apps]

Greptile Summary

This PR performs minor cleanup to the Communicator and evaluator code:

1. Removed unused include: Deleted #include "exceptions.h" from communicator.h as the header doesn't use any symbols from this module.

2. Simplified null checks: Converted implicit boolean conversion patterns (communicator_?) to explicit == nullptr checks for clarity and consistency in evaluator.cpp.

3. Removed redundant availability check: Simplified the device index initialization by removing the is_available() check, which is safe because the validate() function already ensures the communicator is available if non-null in multi-GPU scenarios.

Confidence Score: 5/5

• This PR is safe to merge with minimal risk; it contains only cleanup changes that improve code clarity without altering behavior.
• Score of 5 reflects the straightforward nature of these changes. The removal of the unused include is safe and verified. The null-check style changes are functionally equivalent. The removal of the redundant is_available() check is safe because the validate() function at construction time (line 63 of evaluator.cpp) already guarantees that any non-null communicator is available for multi-GPU scenarios. All changes are low-risk refactoring with no functional impact.
• No files require special attention

Important Files Changed

Filename	Overview
csrc/multidevice/communicator.h	Removed unused include of exceptions.h. The header file only uses NVF_API macro (defined in visibility.h, which is already included) and does not reference any symbols from exceptions.h.
csrc/host_ir/evaluator.cpp	Simplified null-check style from implicit boolean conversion to explicit == nullptr comparisons, and removed redundant is_available() check. Safe because validate() function already ensures communicator is available if non-null and multi-GPU is used.

Sequence Diagram

sequenceDiagram
    participant User
    participant HostIrEvaluator as HostIrEvaluator<br/>Constructor
    participant Validate as validate()
    participant Communicator as Communicator

    User->>HostIrEvaluator: Initialize with<br/>communicator_

    HostIrEvaluator->>HostIrEvaluator: Set my_local_device_index_<br/>(now: explicit nullptr check)

    HostIrEvaluator->>HostIrEvaluator: Set device_index<br/>(now: no is_available check<br/>still safe)

    HostIrEvaluator->>Validate: Call validate()

    Validate->>Validate: Check GPU count

    alt Multi-GPU Scenario
        Validate->>Communicator: Check is_available()
        Communicator-->>Validate: Return availability status
        Validate->>Validate: Validate world size and<br/>local size
    else Single GPU
        Validate->>Validate: Return early
    end

    Validate-->>HostIrEvaluator: Validation complete

    HostIrEvaluator-->>User: Constructor complete

Loading

[wujingyue]

deviceId() returns 0 when the communicator isn't available:

Fuser/csrc/multidevice/communicator.cpp

Line 179 in d395676

rank_(0),