[Bug debug/51570] New: [4.7 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[Bug debug/51570] New: [4.7 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51570

             Bug #: 51570
           Summary: [4.7 Regression] FAIL: gcc.dg/guality/pr45003-[23].c
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: debug
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: rguenth@gcc.gnu.org
            Target: x86_64-*-*


I see the following FAILs with the most recent gdb installed (7.3):

FAIL: gcc.dg/guality/pr45003-2.c  -O1  line 10 a == 0x8078
FAIL: gcc.dg/guality/pr45003-2.c  -O1  line 19 a == 0xffff8078
FAIL: gcc.dg/guality/pr45003-2.c  -O2  line 10 a == 0x8078
FAIL: gcc.dg/guality/pr45003-2.c  -O2  line 19 a == 0xffff8078
FAIL: gcc.dg/guality/pr45003-2.c  -O3 -fomit-frame-pointer  line 10 a == 0x8078
FAIL: gcc.dg/guality/pr45003-2.c  -O3 -fomit-frame-pointer  line 19 a ==
0xffff8078
FAIL: gcc.dg/guality/pr45003-2.c  -O3 -g  line 10 a == 0x8078
FAIL: gcc.dg/guality/pr45003-2.c  -O3 -g  line 19 a == 0xffff8078
FAIL: gcc.dg/guality/pr45003-2.c  -Os  line 10 a == 0x8078
FAIL: gcc.dg/guality/pr45003-2.c  -Os  line 19 a == 0xffff8078
FAIL: gcc.dg/guality/pr45003-2.c  -O2 -flto -fno-use-linker-plugin
-flto-partition=none  line 10 a == 0x8078
FAIL: gcc.dg/guality/pr45003-2.c  -O2 -flto -fno-use-linker-plugin
-flto-partition=none  line 19 a == 0xffff8078
FAIL: gcc.dg/guality/pr45003-2.c  -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  line 10 a == 0x8078
FAIL: gcc.dg/guality/pr45003-2.c  -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  line 19 a == 0xffff8078
FAIL: gcc.dg/guality/pr45003-3.c  -O1  line 10 a == -32648
FAIL: gcc.dg/guality/pr45003-3.c  -O1  line 19 a == 0x8078
FAIL: gcc.dg/guality/pr45003-3.c  -O2  line 10 a == -32648
FAIL: gcc.dg/guality/pr45003-3.c  -O2  line 19 a == 0x8078
FAIL: gcc.dg/guality/pr45003-3.c  -O3 -fomit-frame-pointer  line 10 a == -32648
FAIL: gcc.dg/guality/pr45003-3.c  -O3 -fomit-frame-pointer  line 19 a == 0x8078
FAIL: gcc.dg/guality/pr45003-3.c  -O3 -g  line 10 a == -32648
FAIL: gcc.dg/guality/pr45003-3.c  -O3 -g  line 19 a == 0x8078
FAIL: gcc.dg/guality/pr45003-3.c  -Os  line 10 a == -32648
FAIL: gcc.dg/guality/pr45003-3.c  -Os  line 19 a == 0x8078
FAIL: gcc.dg/guality/pr45003-3.c  -O2 -flto -fno-use-linker-plugin
-flto-partition=none  line 10 a == -32648
FAIL: gcc.dg/guality/pr45003-3.c  -O2 -flto -fno-use-linker-plugin
-flto-partition=none  line 19 a == 0x8078
FAIL: gcc.dg/guality/pr45003-3.c  -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  line 10 a == -32648
FAIL: gcc.dg/guality/pr45003-3.c  -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  line 19 a == 0x8078

they pass for the -m32 multilib though.  No other gdb version tested.

[Bug debug/51570] [4.7 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51570

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.7.0

[Bug debug/51570] [4.7 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51570

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011-12-16
                 CC|                            |aoliva at gcc dot gnu.org,
                   |                            |jakub at gcc dot gnu.org
     Ever Confirmed|0                           |1

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-12-16 09:08:09 UTC ---
This got "broken" by my ENTRY_VALUE patches, and apparently even Alex'
"Keep static VTA locs in cselib tables only" patch doesn't cure it.

We have:
(debug_insn 6 3 7 2 (var_location:HI D#2 (mem:HI (reg/v/f:DI 5 di [orig:62 p ]
[62]) [0 *p_1(D)+0 S2 A16])) pr45003-3.c:8 -1
     (nil))

(debug_insn 7 6 8 2 (var_location:HI D#1 (debug_expr:HI D#2)) pr45003-3.c:8 -1
     (nil))

(debug_insn 8 7 9 2 (var_location:SI a (sign_extend:SI (debug_expr:HI D#1)))
pr45003-3.c:8 -1
     (nil))

(insn:TI 9 8 10 2 (set (reg:SI 5 di [orig:60 D.1725 ] [60])
        (zero_extend:SI (mem:HI (reg/v/f:DI 5 di [orig:62 p ] [62]) [2
*p_1(D)+0 S2 A16]))) pr45003-3.c:9 117 {*zero_extendhisi2_movzwl}
     (nil))

The PR45003 improvement noted during var-tracking the reverse operation of
(zero_extend:SI (mem:HI (di))))
i.e. that the value of D#2 (and D#1) can be computed as (subreg:HI (reg:SI di))
after insn 9.  Thus before ENTRY_VALUE changes, we'd see that the p pointer
value isn't live after that insn anywhere and the only way to compute it would
be to go back, see that (mem:HI (value of p on entry)) is live in (subreg:HI
(reg:SI di)) and just emit the sign extension of it.
Now, with ENTRY_VALUE, even when we keep it as lowest priority alternative,
we have a place where the value of p on entry is live - (entry_value:DI rdi)
and thus we just use it and don't look further.
This testcase will work just fine with GDB 7.4 which finally supports
DW_OP_GNU_entry_value (just verified that), but that wasn't the actual goal of
the testcase, it is trivial to modify the testcase so that it will fail even
with GDB 7.4:

--- gcc/testsuite/gcc.dg/guality/pr45003-3.c.jj    2010-11-19
20:56:33.000000000 +0100
+++ gcc/testsuite/gcc.dg/guality/pr45003-3.c    2011-12-16 10:01:36.170231171
+0100
@@ -24,8 +24,12 @@ int
 main ()
 {
   unsigned short us = 0x8078;
-  foo (&us);
+  unsigned short *pus = &us;
+  asm volatile ("" : "+r" (pus));
+  foo (pus);
   short s = -32648;
-  bar (&s);
+  short *ps = &s;
+  asm volatile ("" : "+r" (ps));
+  bar (ps);
   return 0;
 }

Then on the call site we don't know what is the value passed to the functions,
and as those values aren't needed afterwards, they aren't saved anywhere.
So, yes, entry_value should have the lowest priority of everything.

To fix this we'd need to cache during vt_emit_notes not just a single
expression, but at most two, one that doesn't use any entry_value expressions
and one that does.  To build the complete expressions for the notes we'd first
try if we can build up an expression entirely without any entry_values, and
only if it fails, supply one with entry_values.  If we did no caching, we could
of course just try to expand twice and ignore entry_value in the first round,
but we really can't avoid the caching, the memory consumption and compile time
complexity was huge on some testcases.

[Bug debug/51570] [4.7 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51570

--- Comment #2 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-01-19 12:49:40 UTC ---
Any updates here?  Should we simply XFAIL the tests?

[Bug debug/51570] [4.7 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51570

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-01-19 12:56:53 UTC ---
Then it would XPASS with latest gdb.
With the gdb 7.4.50.20120103-8.fc17 I'm only seeing lots of guality XPASSes on
x86_64 and no FAILs and on i686 again lots of XPASSes and just a single
FAIL: gcc.dg/guality/vla-1.c  -Os  line 17 sizeof (a) == 6
fail.  We definitely need to do something about this, but perhaps it can wait
for 4.8.  Alex, do you think you could look at this?  Thanks.

[Bug debug/51570] [4.7 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51570

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2

--- Comment #4 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-02-27 10:34:31 UTC ---
Thus, P2.  We still should consider XFAILing the tests to make the testsuite
clean.

[Bug debug/51570] [4.7 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[aoliva at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51570

Alexandre Oliva <aoliva at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot       |aoliva at gcc dot gnu.org
                   |gnu.org                     |

--- Comment #5 from Alexandre Oliva <aoliva at gcc dot gnu.org> 2012-02-28 05:48:42 UTC ---
On it (at last!)

[Bug debug/51570] [4.7/4.8 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51570

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.7.0                       |4.7.1

--- Comment #6 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-03-22 08:27:17 UTC ---
GCC 4.7.0 is being released, adjusting target milestone.

[Bug debug/51570] [4.7/4.8 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[aoliva at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51570

--- Comment #7 from Alexandre Oliva <aoliva at gcc dot gnu.org> 2012-04-13 15:56:00 UTC ---
Author: aoliva
Date: Fri Apr 13 15:55:52 2012
New Revision: 186420

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=186420
Log:
PR debug/51570
* var-tracking.c (expand_depth): New type.
(onepart_aux, expand_loc_callback_data): Change depth type to it.
(loc_exp_dep_alloc): Adjust initializer.
(update_depth): Use new type.  Add entryvals.
(vt_expand_var_loc_chain): Take note of expansions with
ENTRY_VALUEs, but don't accept them right away.  Run an optional
second pass accepting the minimum ENTRY_VALUE count found in the
first pass.
(vt_expand_loc_callback, INIT_ELCD): Adjust.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/var-tracking.c

[Bug debug/51570] [4.7 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[aoliva at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51570

Alexandre Oliva <aoliva at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[4.7/4.8 Regression] FAIL:  |[4.7 Regression] FAIL:
                   |gcc.dg/guality/pr45003-[23] |gcc.dg/guality/pr45003-[23]
                   |.c                          |.c

--- Comment #8 from Alexandre Oliva <aoliva at gcc dot gnu.org> 2012-04-18 00:22:23 UTC ---
Fixed in the trunk.  Letting the dust settle before backporting.

[Bug debug/51570] [4.7 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51570

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.7.1                       |4.7.2

--- Comment #9 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-06-14 08:41:26 UTC ---
GCC 4.7.1 is being released, adjusting target milestone.

[Bug debug/51570] [4.7 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51570

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.7.2                       |4.7.3

--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-09-20 10:20:25 UTC ---
GCC 4.7.2 has been released.

[Bug debug/51570] [4.7 Regression] FAIL: gcc.dg/guality/pr45003-[23].c

[aoliva at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51570

Alexandre Oliva <aoliva at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED

--- Comment #11 from Alexandre Oliva <aoliva at gcc dot gnu.org> 2012-11-08 03:06:09 UTC ---
Not backporting.  Fixed.