[RFC] libgcov.c re-factoring and offline profile-tool
Xinliang David Li
davidxl@google.com
Mon Dec 16 22:48:00 GMT 2013
Ok -- gcov_write_counter and gcov_write_tag_length are qualified as
low level primitives for basic gcov format and probably should be kept
in gcov-io.c.
gcov_rewrite is petty much libgcov runtime implementation details so I
think it should be moved out. gcov_write_summary is not related to
gcov low level format either, neither is gcov_seek. Ok for them to be
moved?
thanks,
David
On Mon, Dec 16, 2013 at 2:34 PM, Jan Hubicka <hubicka@ucw.cz> wrote:
>> I think so -- they are private to libgcov. Honza, what do you think?
>
> Hmm, the purpose of gcov-io was to be low level IO library for the basic
> gcov file format. I am not sure if gcov_write_tag_length should really resist
> in other file than gcov_write_tag.
>
> I see a desire to isolate actual stdio calls so one can have replacement driver
> for i.e. Linux kernel. For that reason things like gcov_seek and friends probably
> should be separated, but what is reason for splitting the file handling itself?
>
> Honza
>>
>> 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
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