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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef vm_CodeCoverage_h
#define vm_CodeCoverage_h
#include "mozilla/Vector.h"
#include "ds/LifoAlloc.h"
#include "js/AllocPolicy.h"
#include "js/HashTable.h"
#include "js/TypeDecls.h"
#include "js/Utility.h"
#include "vm/Printer.h"
namespace js {
namespace coverage {
class LCovSource {
public:
LCovSource(LifoAlloc* alloc, JS::UniqueChars name);
// Whether the given script name matches this LCovSource.
bool match(const char* name) const { return strcmp(name_.get(), name) == 0; }
// Whether an OOM was seen recording coverage information. This indicates
// that the resulting coverage information is incomplete.
bool hadOutOfMemory() const { return hadOOM_; }
// Whether the current source is complete and if it can be flushed.
bool isComplete() const { return hasTopLevelScript_; }
// Iterate over the bytecode and collect the lcov output based on the
// ScriptCounts counters.
void writeScript(JSScript* script, const char* scriptName);
// Write the Lcov output in a buffer, such as the one associated with
// the runtime code coverage trace file.
void exportInto(GenericPrinter& out);
private:
// Name of the source file.
JS::UniqueChars name_;
// LifoAlloc strings which hold the filename of each function as
// well as the number of hits for each function.
LSprinter outFN_;
LSprinter outFNDA_;
size_t numFunctionsFound_;
size_t numFunctionsHit_;
// LifoAlloc string which hold branches statistics.
LSprinter outBRDA_;
size_t numBranchesFound_;
size_t numBranchesHit_;
// Holds lines statistics. When processing a line hit count, the hit count
// is added to any hit count already in the hash map so that we handle
// lines that belong to more than one JSScript or function in the same
// source file.
HashMap<size_t, uint64_t, DefaultHasher<size_t>, SystemAllocPolicy> linesHit_;
size_t numLinesInstrumented_;
size_t numLinesHit_;
size_t maxLineHit_;
// Status flags.
bool hasTopLevelScript_ : 1;
bool hadOOM_ : 1;
};
class LCovRealm {
public:
explicit LCovRealm(JS::Realm* realm);
~LCovRealm();
// Write the Lcov output in a buffer, such as the one associated with
// the runtime code coverage trace file.
void exportInto(GenericPrinter& out, bool* isEmpty) const;
friend bool InitScriptCoverage(JSContext* cx, JSScript* script);
private:
// Write the realm name in outTN_.
void writeRealmName(JS::Realm* realm);
// Return the LCovSource entry which matches the given ScriptSourceObject.
LCovSource* lookupOrAdd(const char* name);
// Generate escaped form of script atom and allocate inside our LifoAlloc if
// necessary.
const char* getScriptName(JSScript* script);
private:
typedef mozilla::Vector<LCovSource*, 16, LifoAllocPolicy<Fallible>>
LCovSourceVector;
// LifoAlloc backend for all temporary allocations needed to stash the
// strings to be written in the file.
LifoAlloc alloc_;
// LifoAlloc string which hold the name of the realm.
LSprinter outTN_;
// Vector of all sources which are used in this realm. The entries are
// allocated within the LifoAlloc.
LCovSourceVector sources_;
};
class LCovRuntime {
public:
LCovRuntime();
~LCovRuntime();
// If the environment variable JS_CODE_COVERAGE_OUTPUT_DIR is set to a
// directory, create a file inside this directory which uses the process
// ID, the thread ID and a timestamp to ensure the uniqueness of the
// file.
//
// At the end of the execution, this file should contains the LCOV output of
// all the scripts executed in the current JSRuntime.
void init();
// Write the aggregated result of the code coverage of a realm
// into a file.
void writeLCovResult(LCovRealm& realm);
private:
// When a process forks, the file will remain open, but 2 processes will
// have the same file. To avoid conflicting writes, we open a new file for
// the child process.
void maybeReopenAfterFork();
// Fill an array with the name of the file. Return false if we are unable to
// serialize the filename in this array.
bool fillWithFilename(char* name, size_t length);
// Finish the current opened file, and remove if it does not have any
// content.
void finishFile();
private:
// Output file which is created if code coverage is enabled.
Fprinter out_;
// The process' PID is used to watch for fork. When the process fork,
// we want to close the current file and open a new one.
uint32_t pid_;
// Flag used to report if the generated file is empty or not. If it is empty
// when the runtime is destroyed, then the file would be removed as an empty
// file is not a valid LCov file.
bool isEmpty_;
};
void InitLCov();
void EnableLCov();
inline bool IsLCovEnabled() {
extern bool gLCovIsEnabled;
return gLCovIsEnabled;
}
// Initialize coverage info to track code coverage for a JSScript.
bool InitScriptCoverage(JSContext* cx, JSScript* script);
// Collect the code-coverage data from a script into relevant LCovSource.
bool CollectScriptCoverage(JSScript* script, bool finalizing);
} // namespace coverage
} // namespace js
#endif // vm_Printer_h