nvbench::cpu_timer changed to use steady_clock

[oleksandr-pavlyk]

Closes #370

Using std::chrono::steady_clock is more appropriate for timing measurements. It guarantees that duration computed from two time-points will not contain correction deltas (positive or negative).

[oleksandr-pavlyk]

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📥 Commits

Reviewing files that changed from the base of the PR and between 4a33a61 and 9b0c8ee.

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• nvbench/cpu_timer.cuh

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📝 Walkthrough

Summary by CodeRabbit

Bug Fixes

• Fixed potential negative or incorrect elapsed times in CPU timer measurements.

Walkthrough

The PR modifies nvbench::cpu_timer to ensure CPU timing uses a monotonic clock. A compile-time type alias selects high_resolution_clock when steady, otherwise falls back to steady_clock. A static assertion enforces that the selected clock is steady. The start() and stop() methods now capture time from the selected clock instead of always using high_resolution_clock.

Changes

Steady clock for CPU timing

Layer / File(s)	Summary
Clock type selection and validation nvbench/cpu_timer.cuh	cpu_timer_clock is conditionally aliased to high_resolution_clock (if steady) or steady_clock (if not), with a compile-time assertion ensuring the selected clock is steady. A <type_traits> include is added to support the conditional type selection.
start() and stop() methods updated nvbench/cpu_timer.cuh	cpu_timer::start() and cpu_timer::stop() now call cpu_timer_clock::now() instead of std::chrono::high_resolution_clock::now(), and member types are updated to use time_point_t derived from the selected clock.

Assessment against linked issues

Objective	Addressed	Explanation
Use steady_clock instead of high_resolution_clock for CPU timing [#370]	✅

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