On Thu, Sep 11, 2014 at 10:17 AM, Xinliang David Li <davi...@google.com> wrote:
> Yes, that is what I meant.
>
> David
>
> On Thu, Sep 11, 2014 at 10:09 AM, Teresa Johnson <tejohn...@google.com> wrote:
>> On Wed, Sep 10, 2014 at 3:31 PM, Xinliang David Li <davi...@google.com>
>> wrote:
>>> Can you share the buildinfo reader code with the merger by defininig
>>> some hooks for different callbacks?
>>
>> Do you mean the two blobs of code guarded by 'if (tag ==
>> GCOV_TAG_BUILD_INFO)' that I added here and the existing one in
>> gcov_exit_merge_gcda further down in the same file? Sure, I could
>> outline that and pass in the gi_ptr for the merger case. Let me know
>> if you meant something else.
>>
>> Teresa
>>
>>>
>>> David
>>>
>>> On Wed, Sep 10, 2014 at 10:24 AM, Teresa Johnson <tejohn...@google.com>
>>> wrote:
>>>> While porting recent support for a build info section in the gcda from
>>>> google/4_8 to 4_9 and doing manual testing, I discovered that it does
>>>> not interact well with the COMDAT fixup handling. This patch fixes the
>>>> issue, and adds a test case that exposes the problem without the fix.
>>>>
>>>> Here is the google/4_8 patch - I plan to commit there first then port
>>>> it along with the original build info patch to 4_9.
>>>>
>>>> Passes regression tests - ok for google branches?
>>>>
>>>> Thanks,
>>>> Teresa
Updated patch below. Ok for google branches?
2014-09-11 Teresa Johnson <tejohn...@google.com>
libgcc:
* libgcc/libgcov-driver.c (scan_build_info): New function.
* libgcov-driver.c (gcov_scan_to_function_data): Rename from
gcov_scan_summary_end, scan past BUILD_INFO section.
(gcov_dump_module_info): Rename gcov_scan_summary_end to
gcov_scan_to_function_data, outline BUILD_INFO scan.
gcc/testsuite:
* g++.dg/tree-prof/lipo/buildinfo.txt: Input for
-fprofile-generate-buildinfo option.
* g++.dg/tree-prof/lipo/comdat_fixup_0.C: New test.
* g++.dg/tree-prof/lipo/comdat_fixup_1.C: Ditto.
* g++.dg/tree-prof/lipo/comdat_fixup_2.C: Ditto.
* g++.dg/tree-prof/lipo/comdat_fixup.h: Ditto.
* lib/profopt.exp: Declare srcdir for use in test options.
Index: libgcc/libgcov-driver.c
===================================================================
--- libgcc/libgcov-driver.c (revision 214976)
+++ libgcc/libgcov-driver.c (working copy)
@@ -427,12 +427,53 @@ struct gcov_filename_aux{
/* Including system dependent components. */
#include "libgcov-driver-system.c"
+/* Scan through the build info section at the current position in the
+ open gcda file, assuming its tag has already been written.
+ Return 0 on success, -1 on error. */
+static int
+scan_build_info (struct gcov_info *gi_ptr)
+{
+ gcov_unsigned_t i, length;
+ gcov_unsigned_t num_strings = 0;
+
+ length = gcov_read_unsigned ();
+ char **build_info_strings = gcov_read_build_info (length, &num_strings);
+ if (!build_info_strings)
+ {
+ gcov_error ("profiling:%s:Error reading build info\n", gi_filename);
+ return -1;
+ }
+ if (!gi_ptr->build_info)
+ {
+ gcov_error ("profiling:%s:Mismatched build info sections, expected "
+ "none, found %u strings)\n", gi_filename, num_strings);
+ return -1;
+ }
+
+ for (i = 0; i < num_strings; i++)
+ {
+ if (strcmp (build_info_strings[i], gi_ptr->build_info[i]))
+ {
+ gcov_error ("profiling:%s:Mismatched build info string "
+ "(expected %s, read %s)\n",
+ gi_filename, gi_ptr->build_info[i],
+ build_info_strings[i]);
+ return -1;
+ }
+ free (build_info_strings[i]);
+ }
+ free (build_info_strings);
+ return 0;
+}
+
/* Scan through the current open gcda file corresponding to GI_PTR
- to locate the end position of the last summary, returned in
- SUMMARY_END_POS_P. Return 0 on success, -1 on error. */
+ to locate the end position just before function data should be rewritten,
+ returned in SUMMARY_END_POS_P. E.g. scan past the last summary and other
+ sections that won't be rewritten, like the build info. Return 0 on success,
+ -1 on error. */
static int
-gcov_scan_summary_end (struct gcov_info *gi_ptr,
- gcov_position_t *summary_end_pos_p)
+gcov_scan_to_function_data (struct gcov_info *gi_ptr,
+ gcov_position_t *summary_end_pos_p)
{
gcov_unsigned_t tag, version, stamp;
tag = gcov_read_unsigned ();
@@ -467,6 +508,18 @@ static int
return -1;
}
+ /* If there is a build info section, scan past it as well. */
+ if (tag == GCOV_TAG_BUILD_INFO)
+ {
+ if (scan_build_info (gi_ptr) < 0)
+ return -1;
+
+ *summary_end_pos_p = gcov_position ();
+ tag = gcov_read_unsigned ();
+ }
+ /* The next section should be the function counters. */
+ gcc_assert (tag == GCOV_TAG_FUNCTION);
+
return 0;
}
@@ -484,7 +537,7 @@ gcov_exit_merge_gcda (struct gcov_info *gi_ptr,
struct gcov_parameter_value **merged_parameters)
{
gcov_unsigned_t tag, length, version, stamp;
- unsigned t_ix, f_ix, i;
+ unsigned t_ix, f_ix;
int error = 0;
struct gcov_summary_buffer **sum_tail = &sum_buffer;
@@ -539,35 +592,9 @@ gcov_exit_merge_gcda (struct gcov_info *gi_ptr,
if (tag == GCOV_TAG_BUILD_INFO)
{
- length = gcov_read_unsigned ();
- gcov_unsigned_t num_strings = 0;
- char **build_info_strings = gcov_read_build_info (length, &num_strings);
- if (!build_info_strings)
- {
- gcov_error ("profiling:%s:Error reading build info\n", gi_filename);
- return -1;
- }
- if (!gi_ptr->build_info)
- {
- gcov_error ("profiling:%s:Mismatched build info sections, expected "
- "none, found %u strings)\n", gi_filename, num_strings);
- return -1;
- }
+ if (scan_build_info (gi_ptr) < 0)
+ return -1;
- for (i = 0; i < num_strings; i++)
- {
- if (strcmp (build_info_strings[i], gi_ptr->build_info[i]))
- {
- gcov_error ("profiling:%s:Mismatched build info string "
- "(expected %s, read %s)\n",
- gi_filename, gi_ptr->build_info[i],
- build_info_strings[i]);
- return -1;
- }
- free (build_info_strings[i]);
- }
- free (build_info_strings);
-
/* Since the stamps matched if we got here, this should be from
the same compilation and the build info strings should match. */
tag = gcov_read_unsigned ();
@@ -1031,10 +1058,10 @@ gcov_dump_module_info (struct gcov_filename_aux *g
if (changed)
{
- /* Scan file to find the end of the summary section, which is
+ /* Scan file to find the start of the function section, which is
where we will start re-writing the counters. */
gcov_position_t summary_end_pos;
- if (gcov_scan_summary_end (gi_ptr, &summary_end_pos) == -1)
+ if (gcov_scan_to_function_data (gi_ptr, &summary_end_pos) == -1)
gcov_error ("profiling:%s:Error scanning summaries\n",
gi_filename);
else
Index: gcc/testsuite/g++.dg/tree-prof/lipo/buildinfo.txt
===================================================================
--- gcc/testsuite/g++.dg/tree-prof/lipo/buildinfo.txt (revision 0)
+++ gcc/testsuite/g++.dg/tree-prof/lipo/buildinfo.txt (revision 0)
@@ -0,0 +1 @@
+Test -fprofile-generate-buildinfo option
Index: gcc/testsuite/g++.dg/tree-prof/lipo/comdat_fixup_0.C
===================================================================
--- gcc/testsuite/g++.dg/tree-prof/lipo/comdat_fixup_0.C (revision 0)
+++ gcc/testsuite/g++.dg/tree-prof/lipo/comdat_fixup_0.C (revision 0)
@@ -0,0 +1,9 @@
+/* { dg-options "-O2 -fno-inline
-fprofile-generate-buildinfo=$srcdir/g++.dg/tree-prof/lipo/buildinfo.txt"
} */
+#include <stdio.h>
+
+extern int foo1(int x);
+extern int foo2(int x);
+int main()
+{
+ printf ("Result = %d\n", foo1(1) + foo2(1));
+}
Index: gcc/testsuite/g++.dg/tree-prof/lipo/comdat_fixup_1.C
===================================================================
--- gcc/testsuite/g++.dg/tree-prof/lipo/comdat_fixup_1.C (revision 0)
+++ gcc/testsuite/g++.dg/tree-prof/lipo/comdat_fixup_1.C (revision 0)
@@ -0,0 +1,7 @@
+/* { dg-options "-O2 -fno-inline" } */
+#include "comdat_fixup.h"
+int foo1(int x)
+{
+ Foo f;
+ return f.foo(x);
+}
Index: gcc/testsuite/g++.dg/tree-prof/lipo/comdat_fixup_2.C
===================================================================
--- gcc/testsuite/g++.dg/tree-prof/lipo/comdat_fixup_2.C (revision 0)
+++ gcc/testsuite/g++.dg/tree-prof/lipo/comdat_fixup_2.C (revision 0)
@@ -0,0 +1,7 @@
+/* { dg-options "-O2 -fno-inline" } */
+#include "comdat_fixup.h"
+int foo2(int x)
+{
+ Foo f;
+ return f.foo(x);
+}
Index: gcc/testsuite/g++.dg/tree-prof/lipo/comdat_fixup.h
===================================================================
--- gcc/testsuite/g++.dg/tree-prof/lipo/comdat_fixup.h (revision 0)
+++ gcc/testsuite/g++.dg/tree-prof/lipo/comdat_fixup.h (revision 0)
@@ -0,0 +1,5 @@
+class Foo
+{
+ public:
+ int foo(int x) { return x; }
+};
Index: gcc/testsuite/lib/profopt.exp
===================================================================
--- gcc/testsuite/lib/profopt.exp (revision 214976)
+++ gcc/testsuite/lib/profopt.exp (working copy)
@@ -169,6 +169,8 @@ proc profopt-final-code { which final_code name }
# SRC is the full pathname of the testcase.
#
proc profopt-get-options { src } {
+ global srcdir
+
# dg-options sets a variable called dg-extra-tool-flags.
set dg-extra-tool-flags ""
