google/benchmark

Fail when calculating complexity

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#410 opened on Jun 30, 2017

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enhancementgood first issuehelp wanted

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Description

When calculating time complexity and the range includes 0 it fails upon evaluation.

void BM_Example(benchmark::State& state)
{
  while (state.KeepRunning())
  {
    int i = state.range(0);
  }
  state.SetComplexityN(state.range(0));
}

BENCHMARK(BM_JumpTable)->RangeMultiplier(2)->Range(0, 1)->Complexity(benchmark::o1);

Result

F:\cruft\benchmark\src\complexity.cc:270: benchmark::ComputeBigO: Check (run.complexity_n) > (0)' Failed. Did you forget to call SetComplexityN?

Contributor guide

Research direction
Inspect the assertion in complexity.cc line 270 and handle the case where complexity n is zero.
Tech stack
None
Domain
backend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
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Active
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Clear
Prerequisites
C++Git
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
75