[PATCH 14/17] scripts/code_cov_parse_info: better handle branch filtering

[Kamil Konieczny]

Hi Mauro,
On 2024-02-15 at 11:27:23 +0100, Mauro Carvalho Chehab wrote:
> From: Mauro Carvalho Chehab <mchehab at kernel.org>
> 
> Add an option to filter out branches that aren't associated with
> any functions inside the file (e. g. they came from #inline
> directives).
> 
> While here, also address some issues at the branch report.
> 
> Signed-off-by: Mauro Carvalho Chehab <mchehab at kernel.org>

Acked-by: Kamil Konieczny <kamil.konieczny at linux.intel.com>

> ---
>  scripts/code_cov_parse_info | 71 ++++++++++++++++++++++++++-----------
>  1 file changed, 51 insertions(+), 20 deletions(-)
> 
> diff --git a/scripts/code_cov_parse_info b/scripts/code_cov_parse_info
> index ea4f64b34d2f..57bc4c2f0b4b 100755
> --- a/scripts/code_cov_parse_info
> +++ b/scripts/code_cov_parse_info
> @@ -25,6 +25,8 @@ my @func_exclude_regexes;
>  my %test_names;
>  my @src_include_regexes;
>  my @src_exclude_regexes;
> +my $can_filter_lines = 1;
> +my $ignore_lines_without_functions = 1;
>  
>  my $verbose = 0;
>  my $ignore_unused = 0;
> @@ -161,12 +163,6 @@ sub parse_json_gcov_v1($$)
>  
>  			my $func = $line_ref->{'function_name'};
>  			if (!$func) {
> -				# Ignore DA/BRDA that aren't associated with
> -				# functions. Those are present on header files
> -				# (maybe defines?)
> -				next if (@func_include_regexes);
> -
> -				# Otherwise place them in separate
>  				$func = $before_sf;
>  			} else {
>  				next if is_function_excluded($func);
> @@ -188,9 +184,17 @@ sub parse_json_gcov_v1($$)
>  
>  			my $i = 0;
>  			for my $branch_ref (@{$line_ref->{'branches'}}) {
> -				my $taken = $branch_ref->{'count'};
>  				my $where = sprintf "%d,%d,%d", $ln, 0, $i;
>  
> +				if ($func eq $before_sf) {
> +					# Ignore DA/BRDA that aren't associated with
> +					# functions. Those are present on header files
> +					# (maybe defines?)
> +					next if ($ignore_lines_without_functions);
> +				} else {
> +					$all_branch{$source}{$where}{func} = $func;
> +				}
> +
>  				# Negative gcov results are possible, as
>  				# reported at:
>  				# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67937
> @@ -206,7 +210,8 @@ sub parse_json_gcov_v1($$)
>  					}
>  				}
>  
> -				$all_branch{$source}{$where}{count} += $taken;
> +				$all_branch{$source}{$where}{count} += $branch_ref->{'count'};
> +
>  				$i++;
>  			}
>  			if (!defined($record{files}{$source}{line}{$ln}{branches})) {
> @@ -383,6 +388,10 @@ sub read_info($)
>  	my $func = $before_sf;
>  	my $cur_test = "";
>  
> +	# Info files don't contain functions for lines. So, they can't
> +	# be used to filter lines and branches used inside functions.
> +	$can_filter_lines = 0;
> +
>  	# First step: parse data
>  
>  	# For details on .info file format, see "man geninfo"
> @@ -1231,18 +1240,15 @@ sub check_source_branches()
>  				return;
>  			}
>  
> +			my $func_ln;
>  			my $func = $all_branch{$source}{$where}{func};
> -			my $func_ln = $all_branch{$source}{$where}{func_ln};
> -
> -			print "Branch $source:$ln, ";
>  			if ($func) {
> -				if ($func_ln) {
> -					print "func: $func, ";
> -				} else {
> -					print "func: $func:$func_ln, ";
> -				}
> +				$func_ln = $all_func{$func}{$source}->{ln};
>  			}
> -			print "block $block, branch $branch not taken:\n";
> +
> +			print "Branch $branch on $source:$ln";
> +			print ", function: $func" if ($func);
> +			print " not taken:\n";
>  
>  			if ($func_ln) {
>  				$ctx_lines = $ln - $func_ln;
> @@ -1250,14 +1256,14 @@ sub check_source_branches()
>  				$ctx_lines = 10;
>  			}
>  
> -
>  			# Search for up to $ctx_lines before the occurrence
>  			my $context = "";
>  			my $has_if;
>  			$ln-- if ($ln > 0);
>  			my $delim = "->";
>  			for (my $if_ln = $ln; $if_ln >= 0 && (($ln - $if_ln) < $ctx_lines); $if_ln--) {
> -				$context = "$if_ln$delim\t$lines[$if_ln]" . $context;
> +				my $cur_ln = $if_ln + 1;
> +				$context = "$cur_ln$delim\t$lines[$if_ln]" . $context;
>  				$delim = "";
>  				if ($lines[$if_ln] =~ m/(\bif\b|#if)/) {
>  					$has_if = 1;
> @@ -1267,7 +1273,8 @@ sub check_source_branches()
>  			if ($has_if) {
>  				print $context;
>  			} else {
> -				print "$ln->\t$lines[$ln]";
> +				my $cur_ln = $ln + 1;
> +				print "$cur_ln->\t$lines[$ln]";
>  			}
>  		}
>  	}
> @@ -1308,6 +1315,7 @@ GetOptions(
>  	"source-filters|S=s" => \$src_filters,
>  	"include-source=s" => \@src_include_regexes,
>  	"exclude-source=s" => \@src_exclude_regexes,
> +	"ignore-lines-without-functions!" => \$ignore_lines_without_functions,
>  	"show-files|show_files" => \$show_files,
>  	"show-lines|show_lines" => \$show_lines,
>  	"report|r=s" => \$gen_report,
> @@ -1438,6 +1446,10 @@ print_summary() if ($stat);
>  if ($has_filter) {
>  	my $percent = 100. * $stats{"used_files"} / $stats{"all_files"};
>  
> +	if (!$can_filter_lines) {
> +		printf "Warning......: Function filters won't work with lines/branches\n";
> +	}
> +
>  	printf "Filters......:%s.\n", $filter_str;
>  	printf "Source files.: %.2f%% (%d of %d total)",
>  		$percent, $stats{"used_files"}, $stats{"all_files"};
> @@ -1696,6 +1708,25 @@ report and decrease the code coverage statistics.
>  
>  This option is automaticaly enabled when B<--func-filters> is used.
>  
> +=item B<--ignore-lines-without-functions>
> +
> +This option works only when the input file is in JSON format.
> +
> +Basically, include files may contain several lines of codes that aren't
> +assigned to any functions inside a source file. This is a common behavior
> +for macros and inlined functions inside headers.
> +
> +When this option is selected, the branches stat won't contain any such code.
> +
> +Please notice that this is enabled by default.
> +
> +Use B<--no-ignore-lines-without-functions> to disable it.
> +
> +=item B<--no-ignore-lines-without-functions>
> +
> +Disables filtering out branches that are not associated with any functions
> +inside the source file, but were imported via includes.
> +
>  =back
>  
>  =item B<--show-files> or B<--show_files>
> -- 
> 2.43.0
>