[Bug target/64935] [5 Regression] compare debug failure during building of Linux kernel

[Bug target/64935] [5 Regression] compare debug failure during building of Linux kernel

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

Tobias Burnus <burnus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |burnus at gcc dot gnu.org

--- Comment #2 from Tobias Burnus <burnus at gcc dot gnu.org> ---
Created attachment 34664
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34664&action=edit
Test case failing with g++ -fsanitize=address test.ii

The attached test case fails for me with
  GCC_COMPARE_DEBUG=yes g++ test.ii -fsanitize=address
with the same message:
  g++: error: test.ii: -fcompare-debug failure (length)

[Bug target/64935] [5 Regression] compare debug failure during building of Linux kernel

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

--- Comment #3 from Tobias Burnus <burnus at gcc dot gnu.org> ---
(In reply to Tobias Burnus from comment #2)
> The attached test case fails for me with
> with the same message:
>   g++: error: test.ii: -fcompare-debug failure (length)

That's with x86-64-gnu-linux in my case.

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

--- Comment #4 from Tobias Burnus <burnus at gcc dot gnu.org> ---
(In reply to Markus Trippelsdorf from comment #1)
> Started with r220316. 

Mine (comment 2) also fails with r220315 - but it is also a 5.0 regression.

Hence, I filled a new PR for it: PR64937.

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[mkuvyrkov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

Maxim Kuvyrkov <mkuvyrkov at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |mkuvyrkov at gcc dot gnu.org

--- Comment #5 from Maxim Kuvyrkov <mkuvyrkov at gcc dot gnu.org> ---
Will investigate tomorrow.

The patch in question fixed a debug miscompare problem on arm-linux-gnueabi.

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[trippels at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

--- Comment #6 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
trippels@gcc2-power8 % cat wp512.i
int a[] = {}, b[] = {}, c[] = {}, d[] = {}, e[] = {}, f[] = {}, h[] = {};
int g[] = { 0 };
int i, l, s, w, x, y, z, t2, t3, t5;
unsigned long j, m, o, t4;
long k, n, p, q, r, t, u, v, t1;
fn1 ()
{
  int t6;
  for (; i; i++)
    {
      t5 = a[q] ^ b[p >> 1] ^ c[o >> 1 & 1] ^ d[n >> 1 & 1] ^ e[m >> 1 & 1]
           ^ f[l >> 1 & 1] ^ g[0] ^ h[j & 1];
      t4 = a[j] ^ b[q >> 1] ^ c[p] ^ d[o] ^ e[n] ^ f[m] ^ g[l >> 8] ^ h[k];
      t3 = a[k >> 1] ^ b[j & 5] ^ d[p >> 32] ^ e[o >> 4] ^ f[n >> 6]
           ^ g[m >> 8] ^ h[l];
      t2 = a[l >> 6] ^ b[k & 1] ^ c[j >> 1] ^ d[q >> 32] ^ e[p >> 4]
           ^ f[o >> 6] ^ g[n >> 8] ^ h[m & 1];
      t1 = a[m >> 6] ^ b[l & 1] ^ c[k & 15] ^ d[j >> 2] ^ e[q >> 4] ^ f[p >> 6]
           ^ g[o >> 8] ^ h[n & 1];
      z = a[n >> 56] ^ b[m & 15] ^ c[l & 15] ^ d[k >> 2] ^ e[j >> 4]
          ^ f[q >> 6] ^ g[p >> 8] ^ h[o & 1];
      y = a[o >> 56] ^ b[n & 15] ^ c[m >> 40] ^ d[l >> 2] ^ e[k >> 4]
          ^ f[j >> 6] ^ g[q >> 8] ^ h[p & 1];
      x = a[p >> 56] ^ b[o & 15] ^ c[n >> 40] ^ d[m >> 2] ^ e[l >> 4]
          ^ f[k >> 6] ^ g[j >> 8] ^ h[q & 1];
      q = j = t4;
      k = t3;
      l = t2;
      m = t1;
      n = z;
      o = y;
      p = a[t6] ^ b[0] ^ c[w] ^ d[v] ^ e[u] ^ f[t] ^ g[s] ^ h[r];
      t4 = a[r >> 1] ^ b[t6 & 1] ^ d[w >> 1] ^ e[v >> 1] ^ f[u >> 1]
           ^ g[t >> 1] ^ h[s];
      t3 = a[s >> 6] ^ b[r & 1] ^ c[t6 & 5] ^ d[0] ^ e[w >> 4] ^ f[v >> 6]
           ^ g[u >> 8] ^ h[t & 1];
      t2 = a[t >> 6] ^ b[s] ^ c[r & 15] ^ d[t6 >> 1] ^ e[0] ^ f[w >> 6]
           ^ g[v >> 8] ^ h[u & 1];
      t1 = a[u >> 6] ^ b[t & 15] ^ c[s & 5] ^ d[r >> 32] ^ e[t6 >> 4]
           ^ g[w >> 8] ^ h[v & 1];
      z = a[v >> 56] ^ b[u >> 48 & 1] ^ c[t >> 40 & 1] ^ d[s] ^ e[r >> 1 & 1]
          ^ f[t6 >> 1 & 1] ^ g[0] ^ h[w & 1] ^ z;
      t6 = t5;
      r = t4;
      s = 0;
      t = u = t1;
      v = z;
      w = y;
    }
}

trippels@gcc2-power8 % GCC_COMPARE_DEBUG=1 gcc -std=gnu89 -O2 -c wp512.i
gcc: error: wp512.i: -fcompare-debug failure (length)

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[mkuvyrkov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

--- Comment #7 from Maxim Kuvyrkov <mkuvyrkov at gcc dot gnu.org> ---
Created attachment 34674
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34674&action=edit
Initial patch

Marcus,

Would you please bootstrap / test this patch?

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[mkuvyrkov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

--- Comment #8 from Maxim Kuvyrkov <mkuvyrkov at gcc dot gnu.org> ---
Markus,

I'll test it on x86/x86_64 and arm/aarch64, but I don't have a powerpc box to
bootstrap on.

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[trippels at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

--- Comment #9 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
Your patch bootstraps / tests fine on ppc64. GCC_COMPARE_DEBUG=1 kernel build
also succeeds. 

Thanks.

(If you want access to ppc machines get a compile farm account:
https://gcc.gnu.org/wiki/CompileFarm
There are several POWER boxes available.)

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[trippels at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

--- Comment #10 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
Do you plan to post your patch to gcc-patches, Maxim?

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[mkuvyrkov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

--- Comment #11 from Maxim Kuvyrkov <mkuvyrkov at gcc dot gnu.org> ---
I'm traveling at the moment, and will work on this in the week of Jan 16.

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[law at redhat dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

Jeffrey A. Law <law at redhat dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |zsojka at seznam dot cz

--- Comment #12 from Jeffrey A. Law <law at redhat dot com> ---
*** Bug 64966 has been marked as a duplicate of this bug. ***

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[law at redhat dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

Jeffrey A. Law <law at redhat dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |law at redhat dot com

--- Comment #13 from Jeffrey A. Law <law at redhat dot com> ---
Created attachment 34742
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34742&action=edit
Additional testcase

Additional testcase.  For x86_64


$ gcc -O -fschedule-insns --param=max-sched-ready-insns=0 -fcompare-debug
testcase.c
gcc: error: testcase.c: -fcompare-debug failure

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #14 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Any progress on this?

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[mkuvyrkov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

--- Comment #15 from Maxim Kuvyrkov <mkuvyrkov at gcc dot gnu.org> ---
Working right now.

I'm trying a second approach to fixing this problem more cleanly.

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[mkuvyrkov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

Maxim Kuvyrkov <mkuvyrkov at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #34674|0                           |1
        is obsolete|                            |

--- Comment #16 from Maxim Kuvyrkov <mkuvyrkov at gcc dot gnu.org> ---
Created attachment 34799
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34799&action=edit
Patch v2

I'm happy with this version of the patch and will post it for review after
testing.

Markus, I would appreciate you testing this patch on powerpc to your
satisfaction.

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[trippels at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

--- Comment #17 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
(In reply to Maxim Kuvyrkov from comment #16)
> Created attachment 34799 [details]
> Patch v2
> 
> I'm happy with this version of the patch and will post it for review after
> testing.
> 
> Markus, I would appreciate you testing this patch on powerpc to your
> satisfaction.

Looks good on ppc64. Thanks.

[Bug debug/64935] [5 Regression] compare debug failure during building of Linux kernel

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64935

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

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

--- Comment #18 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Author: mkuvyrkov
Date: Thu Feb 19 08:31:14 2015
New Revision: 220808

URL: https://gcc.gnu.org/viewcvs?rev=220808&root=gcc&view=rev
Log:
Fix PR64935

    * haifa-sched.c (enum rfs_decision, rfs_str): Remove RFS_DEBUG.
    (rank_for_schedule_debug): Update.
    (ready_sort): Make static.  Move sorting logic to ...
    (ready_sort_debug, ready_sort_real): New static functions.
    (schedule_block): Sort both debug insns and real insns in preparation
    for ready list trimming.  Improve debug output.
    * sched-int.h (ready_sort): Remove global declaration.

    * gcc.dg/pr64935-1.c, gcc.dg/pr64935-2.c: New tests.

Added:
    trunk/gcc/testsuite/gcc.dg/pr64935-1.c
    trunk/gcc/testsuite/gcc.dg/pr64935-2.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/haifa-sched.c
    trunk/gcc/sched-int.h
    trunk/gcc/testsuite/ChangeLog