gcov-tool: Add merge-stream subcommand

gcc/

	* doc/gcov-tool.texi: Document merge-stream subcommand.
	* doc/invoke.texi (fprofile-info-section): Mention merge-stream
	subcommand of gcov-tool.
	* gcov-tool.cc (gcov_profile_merge_stream): Declare.
	(print_merge_stream_usage_message): New.
	(merge_stream_usage): Likewise.
	(do_merge_stream): Likewise.
	(print_usage): Call print_merge_stream_usage_message().
	(main): Call do_merge_stream() to execute merge-stream subcommand.

libgcc/

	* libgcov-util.c (consume_stream): New.
	(get_target_profiles_for_merge): Likewise.
	(gcov_profile_merge_stream): Likewise.

2 files changed, 41 insertions, 0 deletions

diff --git a/gcc/doc/gcov-tool.texi b/gcc/doc/gcov-tool.texi
index d79dbc9..7715083 100644
--- a/gcc/doc/gcov-tool.texi
+++ b/gcc/doc/gcov-tool.texi
@@ -53,6 +53,10 @@ Current gcov-tool supports the following functionalities:
 merge two sets of profiles with weights.
 
 @item
+read a stream of profiles with associated filenames and merge it with a set of
+profiles with weights.
+
+@item
 read one set of profile and rewrite profile contents. One can scale or
 normalize the count values.
 @end itemize
@@ -65,6 +69,12 @@ them. One can specify the weight to factor in the relative importance of
 each input.
 
 @item
+Collect profiles from target systems without a filesystem (freestanding
+environments).  Merge the collected profiles with associated profiles
+present on the host system.  One can specify the weight to factor in the
+relative importance of each input.
+
+@item
 Rewrite the profile after removing a subset of the gcda files, while maintaining
 the consistency of the summary and the histogram.
 
@@ -117,6 +127,10 @@ gcov-tool merge [merge-options] @var{directory1} @var{directory2}
      [@option{-v}|@option{--verbose}]
      [@option{-w}|@option{--weight} @var{w1,w2}]
 
+gcov-tool merge-stream [merge-stream-options] [@var{file}]
+     [@option{-v}|@option{--verbose}]
+     [@option{-w}|@option{--weight} @var{w1,w2}]
+
 gcov-tool rewrite [rewrite-options] @var{directory}
      [@option{-n}|@option{--normalize} @var{long_long_value}]
      [@option{-o}|@option{--output} @var{directory}]
@@ -169,6 +183,28 @@ Set the merge weights of the @var{directory1} and @var{directory2},
 respectively. The default weights are 1 for both.
 @end table
 
+@item merge-stream
+Collect profiles with associated filenames from a @emph{gcfn} and @emph{gcda}
+data stream.  Read the stream from the file specified by @var{file} or from
+@file{stdin}.  Merge the profiles with associated profiles in the host
+filesystem.  Apply the optional weights while merging profiles.
+
+For the generation of a @emph{gcfn} and @emph{gcda} data stream on the target
+system, please have a look at the @code{__gcov_filename_to_gcfn()} and
+@code{__gcov_info_to_gcda()} functions declared in @code{#include <gcov.h>}.
+@table @gcctabopt
+
+@item -v
+@itemx --verbose
+Set the verbose mode.
+
+@item -w @var{w1},@var{w2}
+@itemx --weight @var{w1},@var{w2}
+Set the merge weights of the profiles from the @emph{gcfn} and @emph{gcda} data
+stream and the associated profiles in the host filesystem, respectively.  The
+default weights are 1 for both.
+@end table
+
 @item rewrite
 Read the specified profile directory and rewrite to a new directory.
 @table @gcctabopt
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 7cff38b..3f4d6f2 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -15537,6 +15537,11 @@ main (void)
 @}
 @end smallexample
 
+The @command{merge-stream} subcommand of @command{gcov-tool} may be used to
+deserialize the data stream generated by the @code{__gcov_filename_to_gcfn} and
+@code{__gcov_info_to_gcda} functions and merge the profile information into
+@file{.gcda} files on the host filesystem.
+
 @item -fprofile-note=@var{path}
 @opindex fprofile-note