Implementation:ClickHouse ClickHouse Coverage

Knowledge Sources	ClickHouse
Domains	Testing, Instrumentation
Last Updated	2026-02-08 00:00 GMT

Overview

Code coverage instrumentation that collects execution data for test analysis.

Description

Implements custom coverage collection using LLVM sanitizer callbacks. Maintains arrays of executed addresses and provides APIs to retrieve current and cumulative coverage.

Usage

Use for measuring test coverage, implementing coverage-guided fuzzing, or analyzing code execution patterns.

Code Reference

Source Location

• Repository: ClickHouse
• File: base/base/coverage.cpp
• Lines: 1-175

Signature

void dumpCoverageReportIfPossible();

#if defined(SANITIZE_COVERAGE)
std::span<const uintptr_t> getCurrentCoverage();
std::span<const uintptr_t> getCumulativeCoverage();
std::span<const uintptr_t> getAllInstrumentedAddresses();
void resetCoverage();
#endif

Import

#include <base/coverage.h>

Usage Examples

#include <base/coverage.h>

// Reset coverage counters before test
resetCoverage();

// Run test code
run_test();

// Get coverage data
auto coverage = getCurrentCoverage();
for (uintptr_t addr : coverage) {
    // Process covered address
}

// Dump coverage report
dumpCoverageReportIfPossible();

Related Pages

• Principle:ClickHouse_ClickHouse_Code_Coverage_Collection