[PATCH] offline gcda profile processing tool

[Xinliang David Li]

What is the macro to test POSIX IO on host? The guard uses
TARGET_POSIX_IO which is not right.

David

On Fri, Jul 11, 2014 at 1:12 AM, Christophe Lyon
<christophe.lyon@linaro.org> wrote:
> On 11 July 2014 10:07, Richard Biener <richard.guenther@gmail.com> wrote:
>> On Mon, May 5, 2014 at 7:17 PM, Rong Xu <xur@google.com> wrote:
>>> Here is the updated patch. The difference with patch set 3 is
>>> (1) use the gcov-counter.def for scaling operation.
>>> (2) fix wrong scaling function for time-profiler.
>>>
>>> passed with bootstrap, profiledboostrap and SPEC2006.
>>
>> One of the patches breaks bootstrap for me:
>>
>> /space/rguenther/src/svn/trunk/gcc/../libgcc/libgcov.h:184: error: ISO
>> C++ forbids zero-size array ‘ctrs’
>> make[3]: *** [libgcov-util.o] Error 1
>>
>> host compiler is gcc 4.3.4
>>
>> Richard.
>>
>
> On my side, commit 212448 breaks the cross-build of GCC for targets
> using newlib:
> * arm-none-eabi
> * aarch64-none-elf
> /usr/include/sys/stat.h: In function <80><98>void
> gcov_output_files(const char*, gcov_info*)<80><99>:
> /usr/include/sys/stat.h:317: error: too few arguments to function
> <80><98>int mkdir(const char*, __mode_t)<80><99>
> /tmp/1392958_1.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/gcc/gcov-tool.c:96:
> error: at this point in file
> make[2]: *** [gcov-tool.o] Error 1
>
> Christophe.
>
>>> Thanks,
>>>
>>> -Rong
>>>
>>> On Thu, May 1, 2014 at 3:37 PM, Rong Xu <xur@google.com> wrote:
>>>> Hi, Honza,
>>>>
>>>> Please find the new patch in the attachment. This patch integrated
>>>> your earlier suggestions. The noticeable changes are:
>>>> (1) build specialized object for libgcov-driver.c and libgcov-merge.c
>>>> and link into gcov-tool, rather including the source file.
>>>> (2) split some gcov counter definition code to gcov-counter.def to
>>>> avoid code duplication.
>>>> (3) use a macro for gcov_read_counter(), so gcov-tool can use existing
>>>> code in libgcov-merge.c with minimal change.
>>>>
>>>> This patch does not address the suggestion of creating a new directory
>>>> for libgcov. I agree with you that's a much better
>>>> and cleaner structure we should go for. We can do that in follow-up patches.
>>>>
>>>> I tested this patch with boostrap and profiledbootstrap. Other tests
>>>> are on-going.
>>>>
>>>> Thanks,
>>>>
>>>> -Rong
>>>>
>>>> On Wed, Apr 16, 2014 at 8:34 PM, Jan Hubicka <hubicka@ucw.cz> wrote:
>>>>>> GCOT_TOOL needs to use this function to read the string in gcda file
>>>>>> to memory to construct gcov_info objects.
>>>>>> As you noticed, gcov runtime does not need this interface. But
>>>>>> gcov-tool links with gcov runtime and it also uses the function.
>>>>>> We could make it available in gcov_runtime, but that will slightly
>>>>>> increase the memory footprint.
>>>>>
>>>>> Yep, it is not really pretty. I wrote bellow some plan how things may be
>>>>> structured in more convenient way.  Any work in that direction would be welcome.
>>>>>>
>>>>>> The planned new functions for trunk version is: (1) overlap score b/w
>>>>>> two profiles (2) better dumping (top hot objects/function/counters)
>>>>>> and statistics.
>>>>>> Once this basic version is in, we can start to add the new functionality.
>>>>>
>>>>> Sounds good. I assume the autoFDO does not go via gcov tool but rather uses
>>>>> custom reader of profile data at GCC side?
>>>>> I wonder, are there any recent overview papers/slides/text of design of AutoFDO
>>>>> and other features to be merged?
>>>>> I remember the talk from GCC Summit and I did read some of pre-LTO LIPO
>>>>> sources & papers, but it would be nice to have somethin up to date.
>>>>>>
>>>>>> libgcov-util.o is built in gcc/ directory, rather in libgcc.
>>>>>> It's directly linked to gcov-tool.
>>>>>> So libgcov-util.o is built for HOST, not TARGET.
>>>>>> With makefile changes, we can built HOST version of libgcov-driver.o
>>>>>> and libgcov-merge.o.
>>>>>> I also need to make some static functions/variables public.
>>>>>
>>>>> I suppose that can go with IN_GCOV_TOOL ifdef.
>>>>>
>>>>> So we currently have basic gcov io handling in gcc/gcov-io.c that is borrowed
>>>>> by libgcc/libgcov* code.  We also will get libgcov-util.c in libgcc directory
>>>>> that is actually borrowed by by gcc/gcov-tool.c code.
>>>>>
>>>>> We now have one runtime using STDIO for streaming and kernel has custom version
>>>>> that goes via /proc interface (last time I looked).  We added some abstraction
>>>>> into libgcov-interface that is the part that relies on STDIO, partly via gcov-io.c
>>>>> code and now we have in-memory handling code in libgcov-util.
>>>>>
>>>>> I guess it would make most sentse to put all the gcov code into a new directory
>>>>> (libgcov) and make it stand-alone library that can be configured
>>>>> 1) for stdio based runtime as we do not
>>>>> 2) for runtime missing the interface and relyin on user providing it
>>>>> 3) for use within gcov file manipulation tools with reorg of
>>>>> GCC/gcov/gcov-dump/gcov-tool to all use the same low-level interfaces.
>>>>> In a longer term, I would like to make FDO profiling intstrumentation to happen
>>>>> at linktime. For that I need to make the instrumentation code (minimal spaning
>>>>> tree & friends) to work w/o cgraph that would ideally be done in a shared
>>>>> implementation
>>>>>> > Won't this get wrong answer when counters[0] is not the same?
>>>>>> > I would expected the merging code to compare the counters first. Similarly for delta counter.
>>>>>>
>>>>>> These *_op functions are for scaling only. So there is only one
>>>>>> profile involved (thus there is no comparison).
>>>>>> The merge handles are in libgcov-merge.c which have the code to handle
>>>>>> mismatched profile targets.
>>>>>
>>>>> I see, OK then.
>>>>>> >
>>>>>> > Adding correct rounding may actually make difference for Martin's startup time work.
>>>>>>
>>>>>> Do you mean to use something like in RDIV macro?
>>>>>
>>>>> Yes.
>>>>>
>>>>> Honza