Skip to content

Latest commit

 

History

History
75 lines (61 loc) · 3.44 KB

GUIDELINES.md

File metadata and controls

75 lines (61 loc) · 3.44 KB
Raw

File to cover guidelines for NEO project.

C++ usage

  • use c++ style casts instead of c style casts.
  • do not use default parameters
  • prefer using over typedef
  • avoid defines for constants, use constexpr
  • prefer forward declarations in headers
  • avoid includes in headers unless absolutely necessary
  • use of exceptions in driver code needs strong justification
  • prefer static create methods returning std::unique_ptr instead of throwing from constructor
  • inside methods, use an explicit this-> pointer for refering to non-static class members
  • avoid defining global constants with internal-linkage in header files; use inline variables from C++17 instead

Naming conventions

  • use snake_case for new files
  • use PascalCase for class, struct, enum, and namespace names
  • use camelCase for variable and function names
  • prefer verbose names for variables and functions
bad examples : sld, elws, aws
good examples : sourceLevelDebugger, enqueuedLocalWorkGroupSize, actualWorkGroupSize
  • follow givenWhenThen test naming pattern, indicate what is interesting in the test

bad examples :

TEST(CsrTests, initialize)
TEST(CQTests, simple)
TEST(CQTests, basic)
TEST(CQTests, works)

good examples:

TEST(CommandStreamReceiverTests, givenCommandStreamReceiverWhenItIsInitializedThenProperFieldsAreSet)
TEST(CommandQueueTests, givenCommandQueueWhenEnqueueIsDoneThenTaskLevelIsModifed)
TEST(CommandQueueTests, givenCommandQueueWithDefaultParamtersWhenEnqueueIsDoneThenTaskCountIncreases)
TEST(CommandQueueTests, givenCommandQueueWhenEnqueueWithBlockingFlagIsSetThenDriverWaitsUntilAllCommandsAreCompleted)

Testing mindset

  • Test behaviors instead of implementations, do not focus on adding a test per every function in the class (avoid tests for setters and getters), focus on the functionality you are adding and how it changes the driver behavior, do not bind tests to implementation.
  • Make sure that test is fast, our test suite needs to complete in seconds for efficient development pace, as a general rule test shouldn't be longer then 1ms in Debug driver.

Coding guidelines

  • Favor the design of a self-explanatory code over the use of comments; if comments are needed, use double slash instead of block comments
  • HW commands and structures used in NEO must be initialized with constants defines for each Gfx Family: i.e. PIPE_CONTROL cmd = GfxFamily::cmdInitPipeControl
  • Any new HW command or structure must have its own static constant initializer added to any Gfx Family that is going to use it.
  • One-line branches use braces
  • Headers are guarded using #pragma once
  • Do not use TODOs in the code
  • Use UNRECOVERABLE_IF and DEBUG_BREAK_IF instead of asserts:
    • Use UNRECOVERABLE_IF when a failure is found and driver cannot proceed with normal execution. UNRECOVERABLE_IF is implemented in Release and Debug builds.
    • Use DEBUG_BREAK_IF when a failure can be handled gracefully by the driver and it can continue with normal execution. DEBUG_BREAK_IF is only implemented in Debug builds.

UNRECOVERABLE_IF macro

The NEO code uses the UNRECOVERABLE macro to abort execution in the following cases:

  • Driver is in an undefined state from which it cannot recover nor easily return error code
  • Execution entered an unexpected path that is not supported

The abort mechanism guarantees that the error is caught as early as possible, which makes debug and fixing easier.