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Re: [RFC] libgcov.c re-factoring and offline profile-tool
- From: Xinliang David Li <davidxl at google dot com>
- To: Teresa Johnson <tejohnson at google dot com>
- Cc: Jan Hubicka <hubicka at ucw dot cz>, Rong Xu <xur at google dot com>, GCC Patches <gcc-patches at gcc dot gnu dot org>
- Date: Mon, 16 Dec 2013 13:51:40 -0800
- Subject: Re: [RFC] libgcov.c re-factoring and offline profile-tool
- Authentication-results: sourceware.org; auth=none
- References: <CAF1bQ=Qy6--WX-bLYZ8aWXjVVu4pW-H3U+PkATgXwg5c7MZsBg at mail dot gmail dot com> <CAAkRFZ+-tLZqUNQRtu7jN3d3BYG8oi-+q0J6pkduHp5GS3oTkQ at mail dot gmail dot com> <20131104095529 dot GB28992 at kam dot mff dot cuni dot cz> <CAF1bQ=THYY8NqoJ0XDYxnFS9=j9P6-5nLwA6nX1bA+0v1zmUoQ at mail dot gmail dot com> <20131111150245 dot GB6009 at atrey dot karlin dot mff dot cuni dot cz> <CAF1bQ=RSUQdE0tkeqeHnbiNkC=PFPDU6O+zLFNA6jUxqV_aAbg at mail dot gmail dot com> <CAF1bQ=SCtewMrgjcYg4v21jA8uWy_9U=9sB9ULznS=9tdJD8mQ at mail dot gmail dot com> <CAF1bQ=TyNC_rAo1V8Zk9ovOvYAtpqVtep_h7WNLk6v6ZerdcaQ at mail dot gmail dot com> <20131206142319 dot GC32664 at kam dot mff dot cuni dot cz> <CAAe5K+UouGttAzYMwqHtyMSu2sD=KSVhGZ=5oySq=a-7oy2rwg at mail dot gmail dot com> <CAAe5K+XCo9S4Sx3wbeQcPHvyssPGV9Njoz3s7EK6j+kFkZZ9dg at mail dot gmail dot com> <CAAkRFZJ12Z_DOLgbGNqk0iFkx=aai4JxWgp2vaZdM2-4VWPWKg at mail dot gmail dot com> <CAAe5K+WZTGm-7=L-p2FO9qY4xOCteNQDsE=Eb_bPo+FPdvMR1g at mail dot gmail dot com>
I think so -- they are private to libgcov. Honza, what do you think?
thanks,
David
On Mon, Dec 16, 2013 at 1:17 PM, Teresa Johnson <tejohnson@google.com> wrote:
> On Mon, Dec 16, 2013 at 12:55 PM, Xinliang David Li <davidxl@google.com> wrote:
>> gcov_rewrite function is only needed (and defined) with IN_LIBGCOV.
>> Should it be moved from common file gcov-io.c to libgcov.c?
>
> Possibly. I just looked through gcov-io.c and there are several
> additional functions that are only defined under "#ifdef IN_LIBGCOV"
> and only used in libgcov*c (or each other):
>
> gcov_write_counter
> gcov_write_tag_length
> gcov_write_summary
> gcov_seek
>
> Should they all, plus gcov_rewrite, be moved to libgcov-driver.c?
>
> Teresa
>
>>
>>
>> David
>>
>> On Thu, Dec 12, 2013 at 12:11 PM, Teresa Johnson <tejohnson@google.com> wrote:
>>> On Wed, Dec 11, 2013 at 10:05 PM, Teresa Johnson <tejohnson@google.com> wrote:
>>>> On Fri, Dec 6, 2013 at 6:23 AM, Jan Hubicka <hubicka@ucw.cz> wrote:
>>>>>> Hi, all
>>>>>>
>>>>>> This is the new patch for gcov-tool (previously profile-tool).
>>>>>>
>>>>>> Honza: can you comment on the new merge interface? David posted some
>>>>>> comments in an earlier email and we want to know what's your opinion.
>>>>>>
>>>>>> Test patch has been tested with boostrap, regresssion,
>>>>>> profiledbootstrap and SPEC2006.
>>>>>>
>>>>>> Noticeable changes from the earlier version:
>>>>>>
>>>>>> 1. create a new file libgcov.h and move libgcov-*.h headers to libgcov.h
>>>>>> So we can included multiple libgcov-*.c without adding new macros.
>>>>>>
>>>>>> 2. split libgcov.h specific code in gcvo-io.h to libcc/libgcov.h
>>>>>> Avoid multiple-page of code under IN_LIBGCOV macro -- this
>>>>>> improves the readability.
>>>>>>
>>>>>> 3. make gcov_var static, and move the definition from gcov-io.h to
>>>>>> gcov-io.c. Also
>>>>>> move some static functions accessing gcov_var to gcvo-io.c
>>>>>> Current code rely on GCOV_LINKAGE tricks to avoid multi-definition. I don't see
>>>>>> a reason that gcov_var needs to exposed as a global.
>>>>>>
>>>>>> 4. expose gcov_write_strings() and gcov_sync() to gcov_tool usage
>>>>>>
>>>>>> 5. rename profile-tool to gcov-tool per Honza's suggestion.
>>>>>>
>>>>>> Thanks,
>>>>>
>>>>> Hi,
>>>>> I did not read in deatil the gcov-tool source itself, but lets first make the interface changes
>>>>> needed.
>>>>>
>>>>>> 2013-11-18 Rong Xu <xur@google.com>
>>>>>>
>>>>>> * gcc/gcov-io.c (gcov_var): Moved from gcov-io.h and make it static.
>>>>>> (gcov_position): Move from gcov-io.h
>>>>>> (gcov_is_error): Ditto.
>>>>>> (gcov_rewrite): Ditto.
>>>>>> * gcc/gcov-io.h: Re-factoring. Move gcov_var to gcov-io.h and
>>>>>> move the libgcov only part of libgcc/libgcov.h.
>>>>>> * libgcc/libgcov.h: New common header files for libgcov-*.h
>>>>>> * libgcc/Makefile.in: Add dependence to libgcov.h
>>>>>> * libgcc/libgcov-profiler.c: Use libgcov.h
>>>>>> * libgcc/libgcov-driver.c: Ditto.
>>>>>> * libgcc/libgcov-interface.c: Ditto.
>>>>>> * libgcc/libgcov-driver-system.c (allocate_filename_struct): use
>>>>>> xmalloc instread of malloc.
>>>>>> * libgcc/libgcov-merge.c (void __gcov_merge_delta): Add more
>>>>>> parameters to merge function.
>>>>>> (__gcov_merge_add): Ditto.
>>>>>> (__gcov_merge_ior): Ditto.
>>>>>> (__gcov_merge_time_profile): Ditto.
>>>>>> (__gcov_merge_single): Ditto.
>>>>>> (__gcov_merge_delta): Ditto.
>>>>>> * libgcc/libgcov-tool.c (void gcov_tool_set_verbose): New for
>>>>>> gcov-tool support.
>>>>>> (set_fn_ctrs): Ditto.
>>>>>> (tag_function): Ditto.
>>>>>> (tag_blocks): Ditto.
>>>>>> (tag_arcs): Ditto.
>>>>>> (tag_lines): Ditto.
>>>>>> (tag_counters): Ditto.
>>>>>> (tag_summary): Ditto.
>>>>>> (read_gcda_finalize): Ditto.
>>>>>> (read_gcda_file): Ditto.
>>>>>> (ftw_read_file): Ditto.
>>>>>> (read_profile_dir_init) Ditto.:
>>>>>> (gcov_read_profile_dir): Ditto.
>>>>>> (gcov_merge): Ditto.
>>>>>> (find_match_gcov_inf Ditto.o):
>>>>>> (gcov_profile_merge): Ditto.
>>>>>> (__gcov_scale_add): Ditto.
>>>>>> (__gcov_scale_ior): Ditto.
>>>>>> (__gcov_scale_delta): Ditto.
>>>>>> (__gcov_scale_single): Ditto.
>>>>>> (gcov_profile_scale): Ditto.
>>>>>> (gcov_profile_normalize): Ditto.
>>>>>> (__gcov_scale2_add): Ditto.
>>>>>> (__gcov_scale2_ior): Ditto.
>>>>>> (__gcov_scale2_delta): Ditto.
>>>>>> (__gcov_scale2_single): Ditto.
>>>>>> (gcov_profile_scale2): Ditto.
>>>>>> * gcc/gcov-tool.c (unlink_file): Gcov-tool driver support.
>>>>>> (unlink_dir): Ditto.
>>>>>> (profile_merge): Ditto.
>>>>>> (print_merge_usage_message): Ditto.
>>>>>> (merge_usage): Ditto.
>>>>>> (do_merge): Ditto.
>>>>>> (profile_rewrite2): Ditto.
>>>>>> (profile_rewrite): Ditto.
>>>>>> (print_rewrite_usage_message): Ditto.
>>>>>> (rewrite_usage): Ditto.
>>>>>> (do_rewrite): Ditto.
>>>>>> (print_usage): Ditto.
>>>>>> (print_version): Ditto.
>>>>>> (process_args): Ditto.
>>>>>> (main): Ditto.
>>>>>> * gcc/Makefile.in: Build and install gcov-tool.
>>>>>
>>>>>> Index: gcc/gcov-io.c
>>>>>> ===================================================================
>>>>>> --- gcc/gcov-io.c (revision 204895)
>>>>>> +++ gcc/gcov-io.c (working copy)
>>>>>> @@ -36,6 +36,37 @@ static const gcov_unsigned_t *gcov_read_words (uns
>>>>>> static void gcov_allocate (unsigned);
>>>>>> #endif
>>>>>>
>>>>>> +/* Moved for gcov-io.h and make it static. */
>>>>>> +static struct gcov_var gcov_var;
>>>>>
>>>>> This is more an changelog message than a comment in source file.
>>>>> Just describe what gcov_var is.
>>>>
>>>> I changed this so gcov_var is no longer static, but global as before.
>>>>
>>>>>
>>>>> Do you know how the size of libgcov changed with your patch?
>>>>> Quick check of current mainline on compiling empty main gives:
>>>>>
>>>>> jh@gcc10:~/trunk/build/gcc$ cat t.c
>>>>> main()
>>>>> {
>>>>> }
>>>>> jh@gcc10:~/trunk/build/gcc$ ./xgcc -B ./ -O2 -fprofile-generate -o a.out-new --static t.c
>>>>> jh@gcc10:~/trunk/build/gcc$ gcc -O2 -fprofile-generate -o a.out-old --static t.c
>>>>> jh@gcc10:~/trunk/build/gcc$ size a.out-old
>>>>> text data bss dec hex filename
>>>>> 608141 3560 16728 628429 996cd a.out-old
>>>>> jh@gcc10:~/trunk/build/gcc$ size a.out-new
>>>>> text data bss dec hex filename
>>>>> 612621 3688 22880 639189 9c0d5 a.out-new
>>>>>
>>>>> Without profiling I get:
>>>>> jh@gcc10:~/trunk/build/gcc$ size a.out-new-no
>>>>> jh@gcc10:~/trunk/build/gcc$ size a.out-old-no
>>>>> text data bss dec hex filename
>>>>> 599719 3448 12568 615735 96537 a.out-old-no
>>>>> text data bss dec hex filename
>>>>> 600247 3448 12568 616263 96747 a.out-new-no
>>>>>
>>>>> Quite big for empty program, but mostly glibc fault, I suppose
>>>>> (that won't be an issue for embedded platforms). But anyway
>>>>> we increased text size overhead from 8k to 12k, BSS size
>>>>> overhead from 4k to 10k and data by another 1k.
>>>>>
>>>>> text data bss dec hex filename
>>>>> 126 0 0 126 7e _gcov_merge_add.o (ex libgcov.a)
>>>>> 251 0 0 251 fb _gcov_merge_single.o (ex libgcov.a)
>>>>> 242 0 0 242 f2 _gcov_merge_delta.o (ex libgcov.a)
>>>>> 126 0 0 126 7e _gcov_merge_ior.o (ex libgcov.a)
>>>>> 156 0 0 156 9c _gcov_merge_time_profile.o (ex libgcov.a)
>>>>> 89 0 0 89 59 _gcov_interval_profiler.o (ex libgcov.a)
>>>>> 69 0 0 69 45 _gcov_pow2_profiler.o (ex libgcov.a)
>>>>> 115 0 0 115 73 _gcov_one_value_profiler.o (ex libgcov.a)
>>>>> 122 0 0 122 7a _gcov_indirect_call_profiler.o (ex libgcov.a)
>>>>> 57 0 0 57 39 _gcov_average_profiler.o (ex libgcov.a)
>>>>> 52 0 0 52 34 _gcov_ior_profiler.o (ex libgcov.a)
>>>>> 178 0 16 194 c2 _gcov_indirect_call_profiler_v2.o (ex libgcov.a)
>>>>> 77 0 8 85 55 _gcov_time_profiler.o (ex libgcov.a)
>>>>> 126 0 40 166 a6 _gcov_flush.o (ex libgcov.a)
>>>>> 101 0 0 101 65 _gcov_fork.o (ex libgcov.a)
>>>>> 471 0 0 471 1d7 _gcov_execl.o (ex libgcov.a)
>>>>> 471 0 0 471 1d7 _gcov_execlp.o (ex libgcov.a)
>>>>> 524 0 0 524 20c _gcov_execle.o (ex libgcov.a)
>>>>> 98 0 0 98 62 _gcov_execv.o (ex libgcov.a)
>>>>> 98 0 0 98 62 _gcov_execvp.o (ex libgcov.a)
>>>>> 108 0 0 108 6c _gcov_execve.o (ex libgcov.a)
>>>>> 66 0 0 66 42 _gcov_reset.o (ex libgcov.a)
>>>>> 66 0 0 66 42 _gcov_dump.o (ex libgcov.a)
>>>>> 9505 0 6144 15649 3d21 _gcov.o (ex libgcov.a)
>>>>>
>>>>> I think we definitely need to move those 6k of bss space out. I think those are new
>>>>> static vars you introduced that I think are unsafe anyway because multiple streaming
>>>>> may run at once in threaded program where locking mechanizm fails.
>>>>> (it will probably do other bad things, but definitely we do not want to
>>>>> conflict on things like filename to write into).
>>>>>
>>>>> Compared to my system gcov:
>>>>> text data bss dec hex filename
>>>>> 9765 0 64 9829 2665 _gcov.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 125 0 0 125 7d _gcov_merge_add.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 251 0 0 251 fb _gcov_merge_single.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 242 0 0 242 f2 _gcov_merge_delta.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 101 0 0 101 65 _gcov_fork.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 471 0 0 471 1d7 _gcov_execl.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 471 0 0 471 1d7 _gcov_execlp.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 524 0 0 524 20c _gcov_execle.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 98 0 0 98 62 _gcov_execv.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 98 0 0 98 62 _gcov_execvp.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 108 0 0 108 6c _gcov_execve.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 72 0 0 72 48 _gcov_reset.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 72 0 0 72 48 _gcov_dump.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 89 0 0 89 59 _gcov_interval_profiler.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 69 0 0 69 45 _gcov_pow2_profiler.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 115 0 0 115 73 _gcov_one_value_profiler.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 122 0 0 122 7a _gcov_indirect_call_profiler.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 57 0 0 57 39 _gcov_average_profiler.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 52 0 0 52 34 _gcov_ior_profiler.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>> 125 0 0 125 7d _gcov_merge_ior.o (ex ./lib64/gcc/x86_64-suse-linux/4.8/libgcov.a)
>>>>>
>>>>>> Index: gcc/gcov-io.h
>>>>>> ===================================================================
>>>>>> --- gcc/gcov-io.h (revision 204895)
>>>>>> +++ gcc/gcov-io.h (working copy)
>>>>>> @@ -164,51 +164,7 @@ see the files COPYING3 and COPYING.RUNTIME respect
>>>>>> #ifndef GCC_GCOV_IO_H
>>>>>> #define GCC_GCOV_IO_H
>>>>>>
>>>>>> -#if IN_LIBGCOV
>>>>>> -/* About the target */
>>>>>> -
>>>>>> -#if BITS_PER_UNIT == 8
>>>>>> -typedef unsigned gcov_unsigned_t __attribute__ ((mode (SI)));
>>>>>> -typedef unsigned gcov_position_t __attribute__ ((mode (SI)));
>>>>>> -#if LONG_LONG_TYPE_SIZE > 32
>>>>>> -typedef signed gcov_type __attribute__ ((mode (DI)));
>>>>>> -typedef unsigned gcov_type_unsigned __attribute__ ((mode (DI)));
>>>>>> -#else
>>>>>> -typedef signed gcov_type __attribute__ ((mode (SI)));
>>>>>> -typedef unsigned gcov_type_unsigned __attribute__ ((mode (SI)));
>>>>>> -#endif
>>>>>> -#else
>>>>>> -#if BITS_PER_UNIT == 16
>>>>>> -typedef unsigned gcov_unsigned_t __attribute__ ((mode (HI)));
>>>>>> -typedef unsigned gcov_position_t __attribute__ ((mode (HI)));
>>>>>> -#if LONG_LONG_TYPE_SIZE > 32
>>>>>> -typedef signed gcov_type __attribute__ ((mode (SI)));
>>>>>> -typedef unsigned gcov_type_unsigned __attribute__ ((mode (SI)));
>>>>>> -#else
>>>>>> -typedef signed gcov_type __attribute__ ((mode (HI)));
>>>>>> -typedef unsigned gcov_type_unsigned __attribute__ ((mode (HI)));
>>>>>> -#endif
>>>>>> -#else
>>>>>> -typedef unsigned gcov_unsigned_t __attribute__ ((mode (QI)));
>>>>>> -typedef unsigned gcov_position_t __attribute__ ((mode (QI)));
>>>>>> -#if LONG_LONG_TYPE_SIZE > 32
>>>>>> -typedef signed gcov_type __attribute__ ((mode (HI)));
>>>>>> -typedef unsigned gcov_type_unsigned __attribute__ ((mode (HI)));
>>>>>> -#else
>>>>>> -typedef signed gcov_type __attribute__ ((mode (QI)));
>>>>>> -typedef unsigned gcov_type_unsigned __attribute__ ((mode (QI)));
>>>>>> -#endif
>>>>>> -#endif
>>>>>> -#endif
>>>>>
>>>>> So this part basically moves libgcov specific bits into libgcov.h? That OK fine by
>>>>> itself.
>>>>>> Index: libgcc/libgcov-profiler.c
>>>>>> ===================================================================
>>>>>> --- libgcc/libgcov-profiler.c (revision 204895)
>>>>>> +++ libgcc/libgcov-profiler.c (working copy)
>>>>>> @@ -23,15 +23,8 @@ a copy of the GCC Runtime Library Exception along
>>>>>> see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
>>>>>> <http://www.gnu.org/licenses/>. */
>>>>>>
>>>>>> -#include "tconfig.h"
>>>>>> -#include "tsystem.h"
>>>>>> -#include "coretypes.h"
>>>>>> -#include "tm.h"
>>>>>> -#include "libgcc_tm.h"
>>>>>> -
>>>>>> +#include "libgcov.h"
>>>>>> #if !defined(inhibit_libc)
>>>>>> -#define IN_LIBGCOV 1
>>>>>> -#include "gcov-io.h"
>>>>>
>>>>> I did not pay that much attention into the current include file changes, but wasn't
>>>>> idea to avoid #include file to include random other #includes?
>>>>> So perhaps the first block of includes should stay, followed by libgcov.h and gcov-io.h
>>>>> last?
>>>>
>>>> I'm not sure I understand the issue here? The patch basically moves
>>>> the same includes into libgcov.h, and includes that instead. I see
>>>> many other header files in gcc that include other headers.
>>>>
>>>>>> @@ -325,6 +311,9 @@ static struct gcov_summary all_prg;
>>>>>> #endif
>>>>>> /* crc32 for this program. */
>>>>>> static gcov_unsigned_t crc32;
>>>>>> +/* Use this summary checksum rather the computed one if the value is
>>>>>> + * non-zero. */
>>>>>> +static gcov_unsigned_t saved_summary_checksum;
>>>>>
>>>>> Why do you need to save the checksum? Won't it reset summary back with multiple streaming?
>>>>
>>>> This has been removed.
>>>>
>>>>>
>>>>> I would really like to avoid introducing those static vars that are used exclusively
>>>>> by gcov_exit. What about putting them into an gcov_context structure that
>>>>> is passed around the functions that was broken out?
>>>>>> Index: libgcc/libgcov-merge.c
>>>>>> ===================================================================
>>>>>> --- libgcc/libgcov-merge.c (revision 204895)
>>>>>> +++ libgcc/libgcov-merge.c (working copy)
>>>>>> @@ -23,107 +23,150 @@ a copy of the GCC Runtime Library Exception along
>>>>>> see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
>>>>>> <http://www.gnu.org/licenses/>. */
>>>>>>
>>>>>> -#include "tconfig.h"
>>>>>> -#include "tsystem.h"
>>>>>> -#include "coretypes.h"
>>>>>> -#include "tm.h"
>>>>>> -#include "libgcc_tm.h"
>>>>>> +#include "libgcov.h"
>>>>>>
>>>>>> -#if defined(inhibit_libc)
>>>>>> -#define IN_LIBGCOV (-1)
>>>>>> -#else
>>>>>> -#define IN_LIBGCOV 1
>>>>>> +#include "gcov-io-libgcov.h"
>>>>>> #endif
>>>>>>
>>>>>> -#include "gcov-io.h"
>>>>>> -
>>>>>> #if defined(inhibit_libc)
>>>>>> /* If libc and its header files are not available, provide dummy functions. */
>>>>>>
>>>>>> #ifdef L_gcov_merge_add
>>>>>> void __gcov_merge_add (gcov_type *counters __attribute__ ((unused)),
>>>>>> - unsigned n_counters __attribute__ ((unused))) {}
>>>>>> + unsigned n_counters __attribute__ ((unused)),
>>>>>> + unsigned gcov_type *src __attribute__ ((unused)),
>>>>>> + unsigned w __attribute__ ((unused))) {}
>>>>>> #endif
>>>>>>
>>>>>> #ifdef L_gcov_merge_single
>>>>>> void __gcov_merge_single (gcov_type *counters __attribute__ ((unused)),
>>>>>> - unsigned n_counters __attribute__ ((unused))) {}
>>>>>> + unsigned n_counters __attribute__ ((unused)),
>>>>>> + unsigned gcov_type *src __attribute__ ((unused)),
>>>>>> + unsigned w __attribute__ ((unused))) {}
>>>>>> #endif
>>>>>>
>>>>>> #ifdef L_gcov_merge_delta
>>>>>> void __gcov_merge_delta (gcov_type *counters __attribute__ ((unused)),
>>>>>> - unsigned n_counters __attribute__ ((unused))) {}
>>>>>> + unsigned n_counters __attribute__ ((unused)),
>>>>>> + unsigned gcov_type *src __attribute__ ((unused)),
>>>>>> + unsigned w __attribute__ ((unused))) {}
>>>>>> #endif
>>>>>>
>>>>>> #else
>>>>>>
>>>>>> #ifdef L_gcov_merge_add
>>>>>> /* The profile merging function that just adds the counters. It is given
>>>>>> - an array COUNTERS of N_COUNTERS old counters and it reads the same number
>>>>>> - of counters from the gcov file. */
>>>>>> + an array COUNTERS of N_COUNTERS old counters.
>>>>>> + When SRC==NULL, it reads the same number of counters from the gcov file.
>>>>>> + Otherwise, it reads from SRC array. These read values will be multiplied
>>>>>> + by weight W before adding to the old counters. */
>>>>>> void
>>>>>> -__gcov_merge_add (gcov_type *counters, unsigned n_counters)
>>>>>> +__gcov_merge_add (gcov_type *counters, unsigned n_counters,
>>>>>> + gcov_type *src, unsigned w)
>>>>>> {
>>>>>> + int in_mem = (src != 0);
>>>>>> +
>>>>>> for (; n_counters; counters++, n_counters--)
>>>>>> - *counters += gcov_read_counter ();
>>>>>> + {
>>>>>> + gcov_type value;
>>>>>> +
>>>>>> + if (in_mem)
>>>>>> + value = *(src++);
>>>>>> + else
>>>>>> + value = gcov_read_counter ();
>>>>>> +
>>>>>> + *counters += w * value;
>>>>>> + }
>>>>>> }
>>>>>> #endif /* L_gcov_merge_add */
>>>>>>
>>>>>> #ifdef L_gcov_merge_ior
>>>>>> /* The profile merging function that just adds the counters. It is given
>>>>>> - an array COUNTERS of N_COUNTERS old counters and it reads the same number
>>>>>> - of counters from the gcov file. */
>>>>>> + an array COUNTERS of N_COUNTERS old counters.
>>>>>> + When SRC==NULL, it reads the same number of counters from the gcov file.
>>>>>> + Otherwise, it reads from SRC array. */
>>>>>> void
>>>>>> -__gcov_merge_ior (gcov_type *counters, unsigned n_counters)
>>>>>> +__gcov_merge_ior (gcov_type *counters, unsigned n_counters,
>>>>>> + gcov_type *src, unsigned w __attribute__ ((unused)))
>>>>>
>>>>> So the new in-memory variants are introduced for merging tool, while libgcc use gcov_read_counter
>>>>> interface?
>>>>> Perhaps we can actually just duplicate the functions to avoid runtime to do all the scalling
>>>>> and in_mem tests it won't need?
>>>>>
>>>>> I would suggest going with libgcov.h changes and clenaups first, with interface changes next
>>>>> and the gcov-tool is probably quite obvious at the end?
>>>>> Do you think you can split the patch this way?
>>>>>
>>>>> Thanks and sorry for taking long to review. I should have more time again now.
>>>>> Honza
>>>>
>>>> The libgcov.h related changes are in the attached patch. I think it
>>>> addresses your concerns. Bootstrapped and tested on
>>>> x86-64-unknown-linux-gnu. A profiledbootstrap is in progress.
>>>>
>>>> Ok for trunk if profiledbootstrap passes?
>>>
>>> Both a profiledbootstrap and LTO profiledbootstrap pass.
>>>
>>> Teresa
>>>
>>>>
>>>> Thanks,
>>>> Teresa
>>>>
>>>>
>>>> --
>>>> Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413
>>>
>>>
>>>
>>> --
>>> Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413
>
>
>
> --
> Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413