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diff --git a/src/build/debug/Hostboot/Gcov.pm b/src/build/debug/Hostboot/Gcov.pm
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+++ b/src/build/debug/Hostboot/Gcov.pm
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+#!/usr/bin/perl
+#  IBM_PROLOG_BEGIN_TAG
+#  This is an automatically generated prolog.
+#
+#  $Source: src/build/debug/Hostboot/Gcov.pm $
+#
+#  IBM CONFIDENTIAL
+#
+#  COPYRIGHT International Business Machines Corp. 2012
+#
+#  p1
+#
+#  Object Code Only (OCO) source materials
+#  Licensed Internal Code Source Materials
+#  IBM HostBoot Licensed Internal Code
+#
+#  The source code for this program is not published or other-
+#  wise divested of its trade secrets, irrespective of what has
+#  been deposited with the U.S. Copyright Office.
+#
+#  Origin: 30
+#
+#  IBM_PROLOG_END
+
+use strict;
+use File::Path;
+use File::Basename;
+
+package Hostboot::Gcov;
+use Exporter;
+our @EXPORT_OK = ('main');
+
+# NOTE:
+#
+# Neither the in-memory structures or the resulting file format is well
+# documented for GCOV.  I was able to piece together enough of this to
+# make it work for our purposes by looking at gcov-io.h and libgcov.c
+# from the gcc source and gcov/gcc_3_4.c from the linux source.
+#
+# Since this is a Perl script only used internally for debug, I do not see
+# any risk for contamination.  If we decided to give Hostboot to external
+# vendors than this Perl script would be distributed as source which should
+# not lead us into any issues.
+#
+# If you are personally concerned about contamination by reading this
+# code you are hereby warned of the potential.  Proceed at your own choice.
+
+use constant GCOV_EXTENDED_IMAGE_ADDRESS => (1024 * 1024 * 1024);
+use constant GCOV_INFO_HEAD_SYMBOLNAME => "_gcov_info_head";
+
+use constant GCOV_INFO_VERSION_OFFSET => 0;
+use constant GCOV_INFO_NEXT_OFFSET => GCOV_INFO_VERSION_OFFSET + 8;
+use constant GCOV_INFO_TIMESTAMP_OFFSET => GCOV_INFO_NEXT_OFFSET + 8;
+use constant GCOV_INFO_FILENAME_OFFSET => GCOV_INFO_TIMESTAMP_OFFSET + 8;
+use constant GCOV_INFO_NFUNCTIONS_OFFSET => GCOV_INFO_FILENAME_OFFSET + 8;
+use constant GCOV_INFO_FUNCTIONS_OFFSET => GCOV_INFO_NFUNCTIONS_OFFSET + 8;
+use constant GCOV_INFO_CTRMASK_OFFSET => GCOV_INFO_FUNCTIONS_OFFSET + 8;
+use constant GCOV_INFO_COUNTS_OFFSET => GCOV_INFO_CTRMASK_OFFSET + 8;
+
+use constant GCOV_FNINFO_IDENT_OFFSET => 0;
+use constant GCOV_FNINFO_CHECKSUM_OFFSET => GCOV_FNINFO_IDENT_OFFSET + 4;
+use constant GCOV_FNINFO_NCTRS_OFFSET => GCOV_FNINFO_CHECKSUM_OFFSET + 4;
+
+use constant GCOV_CTRINFO_COUNT_OFFSET => 0;
+use constant GCOV_CTRINFO_VALUEPTR_OFFSET => GCOV_CTRINFO_COUNT_OFFSET + 8;
+
+use constant GCOV_GCDA_MAGIC_VALUE => 0x67636461;
+use constant GCOV_FUNCTION_TAG => 0x01000000;
+use constant GCOV_COUNTERS_TAG => 0x01a10000;
+
+# In memory format:
+#       GCC creates a 'gcov_info' structure for each .o file.  The info
+#       structure has a next pointer to form a chain.  In Hostboot we have
+#       organized the chains so that the pointer to the first entry is
+#       stored at [modulename]_gcov_info_head (where modulename = "core" for
+#       kernel and basic system libraries).
+#
+#       The gcov_info has a version id (for the gcc compiled with), a
+#       compile timestamp, c-string with the name of the .gcda file to be
+#       generated, a count of the number of functions in the object, a
+#       pointer to a set of function descriptors, a "counter mask" and a
+#       set of counter descriptors.
+#
+#       GCOV supports multiple types of counters.  The only one we are
+#       interested in is the "ARCS" counter, which describes the number of
+#       times a particular branch is executed.  The other counters are for,
+#       for instance, profiling the value of a particular variable.  The
+#       "counter mask" specifies which counters are instrumented, which
+#       determines the size of some of the array structures, but we only
+#       parse the ARCS-counter type (we do properly calculate sizes if
+#       needed).
+#
+#       Each function descriptor contains an identity number and checksum
+#       pair so the processing tools can match data to code information.
+#       Also the function descriptor has an "n_counters" array which
+#       determines for each counter type how many counters are instrumented.
+#       Again, we are only concerned with the ARCS counter type.
+#
+#       The counter descriptor is a size and pointer to array of counter
+#       values.  If there were 3 functions in the object each with n_counter
+#       values of [3, 5, 2], then the size of the counter descriptor would be
+#       3+5+2 = 10.  The values are arranged such that the first function has
+#       the first 3 values, second one has the next 5, etc.  The relationship
+#       between function descriptor / "n_counters" and counter descriptor
+#       values was not obvious from reading the gcov-io.h.
+#
+#       For more details on these structures search the internet for gcov-io.h
+#       or ask the building block team for the source code to the compiler we
+#       are currently using.  The offsets of all of these structures are all
+#       documented in Perl constants above so you should only need this if
+#       something breaks.
+#
+# .gcda file format:
+#       The gcov tools expect a .gcda (gcov data) file as input, containing the
+#       instrumented counter values, to go along with the .gcno (gcov note)
+#       file created by the compiler.  The format is documented in gcov-io.h
+#       as well but was again not obvious to decipher.
+#
+#       Here is a distilled file format description.  Each entity is an u32.
+#
+#       file : magic version stamp {function counts}*
+#       function: f_header ident checksum
+#       counts: c_header count*
+#       count: lo hi
+#       f_header: F_TAG(=0x01000000) F_LENGTH(=2)
+#       c_header: C_TAG(=0x01a10000) C_LENGTH(=count_length*2)
+#
+#       The file has three u32 of header followed by any number of function
+#       descriptor and count set pairs.  The function descriptor is the
+#       identity and checksum of the function.  The count set is an array of
+#       uint64_ts, containing instrumented counts, for the preceeding function.
+
+# Global of where we want the output to go.
+our $output_dir;
+our $debug_mode;
+BEGIN
+{
+    $debug_mode = 0;
+    $output_dir = "";
+}
+return 1;
+
+sub main
+{
+    # Pick a new output directory based on the time.
+    $output_dir = sprintf "gcov.output.%d/", time;
+    File::Path::mkpath($output_dir);
+
+    # Find all the hostboot modules.
+    my @modules = getModules();
+
+    # Search for the gcov_info object for each module and parse.
+    foreach my $module (@modules)
+    {
+        parseModuleGcov($module);
+    }
+
+    my $pwd = `pwd`;
+    chomp $pwd;
+    ::userDisplay "GCOV output written to: $pwd/$output_dir\n";
+}
+
+sub parseModuleGcov
+{
+    my $module = shift;
+    ::userDisplay "Extracting GCOV info for ".$module."\n";
+
+    # Search for gcov_info chain symbol.
+    my ($gcov_info, $unused) =
+        ::findSymbolAddress($module.GCOV_INFO_HEAD_SYMBOLNAME);
+
+    userDebug("\tFound info at 0x" . (sprintf "%x", $gcov_info) . "\n");
+
+    # TODO: We don't support extended image modules yet because the VMM
+    # debug tools don't exist yet.
+    if ($gcov_info > GCOV_EXTENDED_IMAGE_ADDRESS)
+    {
+        ::userDisplay "\tUnable to parse extended image modules.  Skipped.\n";
+        return;
+    }
+
+    # Check that we found the gcov_info chain.
+    if ($gcov_info == 0)
+    {
+        ::userDisplay "\tUnable to find gcov_info chain.  Skipped.\n";
+        return;
+    }
+
+    # Parse info chain.
+    parseGcovInfo(::read64($gcov_info));
+}
+
+sub parseGcovInfo
+{
+    my $info_ptr = shift;
+    return if (0 eq $info_ptr);
+
+    my $filename = ::readStr(::read64($info_ptr + GCOV_INFO_FILENAME_OFFSET));
+    userDebug("\tFile = ".$filename."\n");
+
+    my $version = ::read32($info_ptr + GCOV_INFO_VERSION_OFFSET);
+    my $stamp = ::read32($info_ptr + GCOV_INFO_TIMESTAMP_OFFSET);
+
+    my $func_count = ::read32($info_ptr + GCOV_INFO_NFUNCTIONS_OFFSET);
+    userDebug("\tFunction Count = ".$func_count."\n");
+
+    my $funcs = ::read64($info_ptr + GCOV_INFO_FUNCTIONS_OFFSET);
+    userDebug("\tFunc Address = ".(sprintf "%x", $funcs)."\n");
+
+    my $ctrmask = ::read32($info_ptr + GCOV_INFO_CTRMASK_OFFSET);
+    if ($ctrmask % 2) # Check that COUNTER_ARCS is turned on.
+    {
+        # COUNTER_ARCS is on.  Create file, find arc-values array,
+        # parse functions.
+
+        my $fd = createGcovFile($filename, $version, $stamp);
+
+        my $arcs_ptr = ::read64($info_ptr + GCOV_INFO_COUNTS_OFFSET +
+                                GCOV_CTRINFO_VALUEPTR_OFFSET);
+        parseGcovFuncs($fd, $funcs, $func_count, $ctrmask, $arcs_ptr);
+
+        close $fd;
+    }
+    else
+    {
+        userDebug("COUNTER_ARCS is missing!\n");
+    }
+
+    # Look for next .o in gcov_info chain, parse.
+    my $next = ::read64($info_ptr + GCOV_INFO_NEXT_OFFSET);
+    parseGcovInfo($next);
+}
+
+sub parseGcovFuncs
+{
+    my $fd = shift;
+    my $func_ptr = shift;
+    my $func_count = shift;
+    my $mask = shift;
+    my $val_ptr = shift;
+
+    my $fn_offset = 0;
+
+    # Need to calculate the number of counters based on the bits on in
+    # the 'mask'.  This is used to determine the size of the function
+    # descriptor object.
+    my $counters = 0;
+    {
+        my $_mask = $mask;
+
+        while (0 != $_mask)
+        {
+            $counters++;
+            $_mask = ($_mask >> 1);
+        }
+    }
+
+    userDebug("\tCounters = ".$counters."\n");
+
+    # Round up the counter count to the nearest two for alignment of the
+    # function descriptor object.
+    if ($counters % 2)
+    {
+        $counters++;
+    }
+    my $func_size = GCOV_FNINFO_CHECKSUM_OFFSET + 4 * $counters;
+
+    userDebug("\tFunction size = ".$func_size."\n");
+
+    # Iterate through the functions and parse.
+    for(my $function = 0; $function < $func_count; $function++)
+    {
+        my $func_off = ($func_ptr + $func_size * $function);
+        my $ident = ::read32($func_off + GCOV_FNINFO_IDENT_OFFSET);
+        my $chksum = ::read32($func_off + GCOV_FNINFO_CHECKSUM_OFFSET);
+
+        userDebug("Ident = ".(sprintf "%x", $ident)."\n");
+        userDebug("Chksum = ".(sprintf "%x", $chksum)."\n");
+
+        print $fd pack('l', GCOV_FUNCTION_TAG);  # Write function tag.
+        print $fd pack('l', 2); # Write size = 2.
+        print $fd pack('l', $ident); # Write ident.
+        print $fd pack('l', $chksum); # Write checksum.
+
+        my $nctr_val = ::read32($func_off + GCOV_FNINFO_NCTRS_OFFSET);
+        userDebug("N-Counters = ".$nctr_val."\n");
+
+        print $fd pack('l', GCOV_COUNTERS_TAG); # Write counter tag.
+        print $fd pack('l', $nctr_val * 2); # Write counter length.
+
+        # Read each counter value, output.
+        for(my $v_idx = 0; $v_idx < $nctr_val; $v_idx++)
+        {
+            my $val = ::read64($val_ptr + 8*($fn_offset + $v_idx));
+            userDebug("\tValue[$v_idx] = ".$val."\n");
+
+            print $fd pack('l', $val & 0xFFFFFFFF);  # Write lower word.
+            print $fd pack('l', $val >> 32) ; # Write upper word.
+        }
+
+        # We used up a number of counters, so move the offset forward for
+        # the next function.
+        $fn_offset += $nctr_val;
+    }
+
+}
+
+# The *.gcda filename found in the gcov_info struct is an absolute path to
+# the corresponding .o file (not the .C file).  This is of the form:
+# ${HOSTBOOTROOT}/src/usr/module/${ROOTPATH}/obj/${MODULE}/foo.gcda .
+# Since we might not even be running this on the same machine, we need to put
+# the output into the "output_dir" but we need to strip off a lot of stuff.
+# The path is going to have an obj in it somewhere so we key off that
+# as the location for where the output file will go.
+sub createGcovFile
+{
+    my $name = shift;
+    my $version = shift;
+    my $stamp = shift;
+
+    # Change *./../obj/ into obj/, prepend output_dir.
+    $name =~ s/.*\/obj\//obj\//;
+    $name = $output_dir.$name;
+
+    # Make sure everything after 'obj/' exists (create subdirs).
+    my $dir = File::Basename::dirname($name);
+    File::Path::mkpath($dir);
+
+    # Create file.
+    open(my $GCOVFILE, "> $name");
+    binmode($GCOVFILE);
+
+    # Write out header.
+    print $GCOVFILE pack('l', GCOV_GCDA_MAGIC_VALUE);
+    print $GCOVFILE pack('l', $version);
+    print $GCOVFILE pack('l', $stamp);
+
+    return $GCOVFILE;
+}
+
+# Search the module list for each code module (lib*.so).  Also add "core"
+# for the kernel instrumentation.
+sub getModules
+{
+    my @modules = ::listModules();
+    my @result = ( "core" );
+
+    foreach my $mod (@modules)
+    {
+        if ($mod =~ m/lib.*\.so$/)
+        {
+            $mod =~ s/lib(.*)\.so/$1/;
+            push @result, $mod;
+        }
+    }
+
+    return @result;
+}
+
+sub userDebug
+{
+    return if (!$debug_mode);
+
+    my $string = shift;
+    ::userDisplay $string;
+}
+
+# Debug tool help info.
+sub helpInfo
+{
+    my %info = (
+        name => "Gcov",
+        intro => [ "Extracts the GCOV information."],
+    );
+}