This patch primarily changes the BENCHMARK_UNREACHABLE()
implementation under MSVC to use __assume(false) instead
of being a NORETURN function, which ironically caused
unreachable code warnings.
Second, since the NOTHROW function attempt generated the
warnings we meant to avoid, it has been replaced with a dummy
null statement.
* Improve CPU Cache info reporting -- Add Windows support.
This patch does a couple of thing regarding CPU Cache reporting.
First, it adds an implementation on Windows. Second it fixes
the JSONReporter to correctly (and actually) output the CPU
configuration information.
And finally, third, it detects and reports the number of
physical CPU's that share the same cache.
* Refactor System information collection.
This patch refactors the system information collection,
and in particular information about the target CPU. The
motivation is to make it easier to access CPU information,
and easier to add new information as need be.
This patch additionally adds information about the cache
sizes of the CPU.
* Address review comments: Clean up integer types.
This commit cleans up the integer types used in ValueUnion to
follow the Google style guide.
Additionally it adds a BENCHMARK_UNREACHABLE macro to assist
in documenting/catching unreachable code paths.
* Rename ValueUnion accessors.
Define BENCHMARK_OS_NETBSD for NetBSD.
Add detection of cpuinfo_cycles_per_second and cpuinfo_num_cpus.
This code shared detection of these properties with FreeBSD.
When stopping a timer, the current time is subtracted
from the start time. However, when the times are identical,
or sufficiently close together, the subtraction can result
in a negative number.
For some reason MinGW is the only platform where this problem
manifests. I suspect it's due to MinGW specific behavior in either
the CPU timing code, floating point model, or printf formatting.
Either way, the fix for MinGW should be correct across all platforms.
This patch improves the performance of the KeepRunning loop in two ways:
(A) it removes the dependency on the max_iterations variable, preventing
it from being loaded every iteration.
(B) it loops to zero, instead of to an upper bound. This allows a single
decrement instruction to be used instead of a arithmetic op followed by a
comparison.
* Drop Stat1, refactor statistics to be user-providable, add median.
My main goal was to add median statistic. Since Stat1
calculated the stats incrementally, and did not store
the values themselves, it is was not possible. Thus,
i have replaced Stat1 with simple std::vector<double>,
containing all the values.
Then, i have refactored current mean/stdev to be a
function that is provided with values vector, and
returns the statistic. While there, it seemed to make
sense to deduplicate the code by storing all the
statistics functions in a map, and then simply iterate
over it. And the interface to add new statistics is
intentionally exposed, so they may be added easily.
The notable change is that Iterations are no longer
displayed as 0 for stdev. Is could be changed, but
i'm not sure how to nicely fit that into the API.
Similarly, this dance about sometimes (for some fields,
for some statistics) dividing by run.iterations, and
then multiplying the calculated stastic back is also
dropped, and if you do the math, i fail to see why
it was needed there in the first place.
Since that was the only use of stat.h, it is removed.
* complexity.h: attempt to fix MSVC build
* Update README.md
* Store statistics to compute in a vector, ensures ordering.
* Add a bit more tests for repetitions.
* Partially address review notes.
* Fix gcc build: drop extra ';'
clang, why didn't you warn me?
* Address review comments.
* double() -> 0.0
* early return
When generating a human-readable number for user counters, we don't
generally expect 1k to be 1024. This is the default due to the more
general purpose string utility.
Fixes#437
* Json reporter: passthrough fp, don't cast it to int; adjust tooling
Json output format is generally meant for further processing
using some automated tools. Thus, it makes sense not to
intentionally limit the precision of the values contained
in the report.
As it can be seen, FormatKV() for doubles, used %.2f format,
which was meant to preserve at least some of the precision.
However, before that function is ever called, the doubles
were already cast to the integer via RoundDouble()...
This is also the case for console reporter, where it makes
sense because the screen space is limited, and this reporter,
however the CSV reporter does output some( decimal digits.
Thus i can only conclude that the loss of the precision
was not really considered, so i have decided to adjust the
code of the json reporter to output the full fp precision.
There can be several reasons why that is the right thing
to do, the bigger the time_unit used, the greater the
precision loss, so i'd say any sort of further processing
(like e.g. tools/compare_bench.py does) is best done
on the values with most precision.
Also, that cast skewed the data away from zero, which
i think may or may not result in false- positives/negatives
in the output of tools/compare_bench.py
* Json reporter: FormatKV(double): address review note
* tools/gbench/report.py: skip benchmarks with different time units
While it may be useful to teach it to operate on the
measurements with different time units, which is now
possible since floats are stored, and not the integers,
but for now at least doing such a sanity-checking
is better than providing misinformation.
Change ThreadCPUUsage to call ProcessCPUUsage if __rtems__ is defined.
RTEMS real time OS doesn't support CLOCK_THREAD_CPUTIME_ID. See
https://github.com/RTEMS/rtems/blob/master/cpukit/posix/src/clockgettime.c#L58-L59
Prior to this change, ThreadCPUUsage would fail when running on RTEMS with:
ERROR: clock_gettime(CLOCK_THREAD_CPUTIME_ID, ...) failed
* Make Benchmark a single header library (but not header-only)
This patch refactors benchmark into a single header, to allow
for slightly easier usage.
The initial reason for the header split was to keep C++ library
components from being included by benchmark_api.h, making that
part of the library STL agnostic. However this has since changed
and there seems to be little reason to separate the reporters from
the rest of the library.
* Fix internal_macros.h
* Remove more references to macros.h
* Add ClearRegisteredBenchmark() function.
Since benchmarks can be registered at runtime using the RegisterBenchmark(...)
functions, it makes sense to have a ClearRegisteredBenchmarks() function too,
that can be used at runtime to clear the currently registered benchmark and
re-register an entirely new set.
This allows users to run a set of registered benchmarks, get the output using
a custom reporter, and then clear and re-register new benchmarks based on the
previous results.
This fixes issue #400, at least partially.
* Remove unused change
Using target_include_directories CMake will implicitly add the the
necessary include paths to targets which link against the benchmark
library. This is useful when the benchmark repo is included as a
subdirectory in another CMake build.
This thing with the pragma ignore was getting out of hand: now
MinGW (and probably GCC) was erroring too. So I chose to move
the definition of IsZero() out of the anonymous namespace into
benchmark.cc.
The problem was that the call to Finish() the user counters was
lost in a big merge. If I had already written the tests for the
user counters, this would probably have been catched earlier.
* fix android compilation
* checking __GLIBCXX__ and __GLIBCPP__ macro in addition to __ANDROID__
* using vsnprintf instead of std::vsnprintf to compile on Android
* removed __GLIBCPP__ check on Android
* StringPrintF instead of std::to_string for Android
When using CPU time to determine the correct number of iterations the
library additionally checks if the benchmark has consumed 5x the minimum
required time according to the wall clock. This prevents benchmarks
with low CPU usage from running for much longer than actually intended.
However when a benchmark uses a manual timer this heuristic isn't helpful
and likely isn't correct since we don't know what the manual timer actually
measures.
This patch removes the above restriction when a benchmark specifies a manual
timer.
* Add Benchmark::Iterations for explicitly specifying the number of iterations to use.
* Document that benchmark::Iterations should not be used to limit benchmark runtimes
- Remove target_include_directories of ${PROJECT_SOURCE_DIR}/include to
fix error: Target "benchmark" INTERFACE_INCLUDE_DIRECTORIES property
contains path which is prefixed in the source directory.
* Fix reading CPU info from file
Macro CHECK do nothing for release mode, meaning it doesn't invoke the
arguments
* Add myself to AUTHORS and CONTRIBUTORS
