llvm/tools/llvm-cov/CoverageSummaryInfo.cpp
Justin Bogner 9bdb194b86 llvm-cov: Simplify coverage reports, fixing PR22575 in the process
PR22575 occurred because we were unsafely storing references into a
std::vector. If the vector moved because it grew, we'd be left
iterating through garbage memory. This avoids the issue by simplifying
the logic to gather coverage information as we go, rather than storing
it and iterating over it.

I'm relying on the existing tests showing that this is semantically
NFC, since it's difficult to hit the issue this fixes without
relatively large covered programs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229215 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-14 02:01:24 +00:00

72 lines
2.5 KiB
C++

//===- CoverageSummaryInfo.cpp - Coverage summary for function/file -------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// These structures are used to represent code coverage metrics
// for functions/files.
//
//===----------------------------------------------------------------------===//
#include "CoverageSummaryInfo.h"
using namespace llvm;
using namespace coverage;
FunctionCoverageSummary
FunctionCoverageSummary::get(const coverage::FunctionRecord &Function) {
// Compute the region coverage
size_t NumCodeRegions = 0, CoveredRegions = 0;
for (auto &CR : Function.CountedRegions) {
if (CR.Kind != CounterMappingRegion::CodeRegion)
continue;
++NumCodeRegions;
if (CR.ExecutionCount != 0)
++CoveredRegions;
}
// Compute the line coverage
size_t NumLines = 0, CoveredLines = 0;
for (unsigned FileID = 0, E = Function.Filenames.size(); FileID < E;
++FileID) {
// Find the line start and end of the function's source code
// in that particular file
unsigned LineStart = std::numeric_limits<unsigned>::max();
unsigned LineEnd = 0;
for (auto &CR : Function.CountedRegions) {
if (CR.FileID != FileID)
continue;
LineStart = std::min(LineStart, CR.LineStart);
LineEnd = std::max(LineEnd, CR.LineEnd);
}
unsigned LineCount = LineEnd - LineStart + 1;
// Get counters
llvm::SmallVector<uint64_t, 16> ExecutionCounts;
ExecutionCounts.resize(LineCount, 0);
for (auto &CR : Function.CountedRegions) {
if (CR.FileID != FileID)
continue;
// Ignore the lines that were skipped by the preprocessor.
auto ExecutionCount = CR.ExecutionCount;
if (CR.Kind == CounterMappingRegion::SkippedRegion) {
LineCount -= CR.LineEnd - CR.LineStart + 1;
ExecutionCount = 1;
}
for (unsigned I = CR.LineStart; I <= CR.LineEnd; ++I)
ExecutionCounts[I - LineStart] = ExecutionCount;
}
CoveredLines += LineCount - std::count(ExecutionCounts.begin(),
ExecutionCounts.end(), 0);
NumLines += LineCount;
}
return FunctionCoverageSummary(
Function.Name, Function.ExecutionCount,
RegionCoverageInfo(CoveredRegions, NumCodeRegions),
LineCoverageInfo(CoveredLines, 0, NumLines));
}