[Bug target/52530] New: [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[Bug target/52530] New: [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[ro at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52530

             Bug #: 52530
           Summary: [4.8 regression] Many 64-bit execution failures on
                    Solaris 10/11 with Sun as
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: ro@gcc.gnu.org
                CC: hjl@gcc.gnu.org, ubizjak@gmail.com
              Host: i386-pc-solaris2.1[01]
            Target: i386-pc-solaris2.1[01]
             Build: i386-pc-solaris2.1[01]


Between 20120302 and 20120307, many 64-bit execution tests all over the
testsuite
started to fail on Solaris 10 and 11/x86 when using Sun as.  With gas, all is
fine.

E.g.

FAIL: gcc.c-torture/execute/20021120-1.c execution,  -O3 -fomit-frame-pointer
-funroll-loops

The test aborts, and can be reproduced with -m64 -O1 -funroll-loops.  If I add
printf's to investigate the failure (gdb cannot print optimized-out values
here),
the failure vanishes.

Between .s files for as and gas, there are no codegen differences when using
-fno-dwarf2-cfi-asm.

When I compare the 4.7 and mainline .s files with as, I find lots of changes
like

--- 20021120-1.s        2012-03-08 13:00:25.054484596 +0100
+++ /var/gcc/regression/trunk/10-gcc/build/gcc/testsuite/gcc/20021120-1.s
2012-03-08 12:48:21.890112842 +0100
@@ -534,37 +534,37 @@
        movsd   %xmm2, gd(,%rcx,8)
        cvtsi2ss        %eax, %xmm3
        movss   %xmm3, gf(,%rcx,4)
-       leal    1(%rax), %edi
+       leal    1(%eax), %edi
        cvtsi2sd        %edi, %xmm4
        movslq  %edi, %r8
        movsd   %xmm4, gd(,%r8,8)

A reghunt revealed that this was caused by this patch:

2012-03-04  H.J. Lu  <hongjiu.lu@intel.com>

       * config/i386/i386.c (ix86_print_operand_address): Only handle
       zero-extended DImode addresses.

I'm now trying another bootstrap with this change reverted to see if this fixes
all the failures.

  Rainer

[Bug target/52530] [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52530

--- Comment #1 from Uros Bizjak <ubizjak at gmail dot com> 2012-03-08 13:49:52 UTC ---
Ouch.

Before the change, we always used "q" modifier for addresses, only in two
special cases we emitted "l". This "q" modifier forced DImode address even for
SImode operands, avoiding addr32 prefixes.

The change - while correct - cancelled this optimization.

So, please revert this patch ASAP.

Also, Sun is buggy in the way addr32 prefix is handled.

[Bug target/52530] [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52530

--- Comment #2 from H.J. Lu <hjl.tools at gmail dot com> 2012-03-08 15:06:32 UTC ---
(In reply to comment #1)
> Ouch.
> 
> Before the change, we always used "q" modifier for addresses, only in two
> special cases we emitted "l". This "q" modifier forced DImode address even for
> SImode operands, avoiding addr32 prefixes.
> 
> The change - while correct - cancelled this optimization.
> 
> So, please revert this patch ASAP.
> 

Uros, can you revert it for me? Thanks.

[Bug target/52530] [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[uros at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52530

--- Comment #3 from uros at gcc dot gnu.org 2012-03-08 15:19:36 UTC ---
Author: uros
Date: Thu Mar  8 15:19:32 2012
New Revision: 185103

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=185103
Log:
    PR target/52530
    Revert:
    2012-03-04  H.J. Lu  <hongjiu.lu@intel.com>

    * config/i386/i386.c (ix86_print_operand_address): Only handle
    zero-extended DImode addresses.


Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/i386/i386.c

[Bug target/52530] [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52530

Uros Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.8.0

--- Comment #4 from Uros Bizjak <ubizjak at gmail dot com> 2012-03-08 18:16:21 UTC ---
Fixed by revert.

[Bug target/52530] [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52530

Uros Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |REOPENED
   Last reconfirmed|                            |2012-03-09
         Resolution|FIXED                       |
     Ever Confirmed|0                           |1

--- Comment #5 from Uros Bizjak <ubizjak at gmail dot com> 2012-03-09 14:55:18 UTC ---
However, there is a problem with Pmode != DImode. Consider following test:

struct foo
{
  int *f;
  int i;
};

void
__attribute__ ((noinline))
bar (struct foo x)
{
  *(x.f) = 1;
}

This will compile with -mx32 to:

bar:
       movl    $1, (%rdi)
       ret

which is wrong.

The move is:

#(insn:TI 6 3 13 2 (set (mem:SI (reg:SI 5 di [orig:60 x ] [60]) [4 *D.1704_1+0
S4 A32])
#        (const_int 1 [0x1])) ptr.c:11 64 {*movsi_internal}
#     (expr_list:REG_DEAD (reg:SI 5 di [orig:60 x ] [60])
#        (nil)))
        movl    $1, (%rdi)      # 6     *movsi_internal/2       [length = 6]

So we want to output address in SImode, while avoiding addr32 prefixes for
LEAs.

The patch from H.J. should be applied and LEAs should be fixed.

[Bug target/52530] [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52530

--- Comment #6 from H.J. Lu <hjl.tools at gmail dot com> 2012-03-09 15:17:07 UTC ---
This patch works for me:

---
diff --git a/gcc/ChangeLog.addr32 b/gcc/ChangeLog.addr32
index 066f1ec..a191e47 100644
--- a/gcc/ChangeLog.addr32
+++ b/gcc/ChangeLog.addr32
@@ -1,3 +1,8 @@
+2012-03-08  H.J. Lu  <hongjiu.lu@intel.com>
+
+    * config/i386/i386.c (ix86_print_operand_address): Only handle
+    zero-extended DImode addresses if Pmode == DImode.
+
 2012-03-06  Uros Bizjak  <ubizjak@gmail.com>

     * config/i386/i386.md (*zero_extendsidi2_rex64): Allow loading
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 69cb6ae..c2cad5a 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -14548,7 +14548,7 @@ ix86_print_operand_address (FILE *file, rtx addr)

       /* Print SImode registers for zero-extended addresses to force
      addr32 prefix.  Otherwise print DImode registers to avoid it.  */
-      if (TARGET_64BIT)
+      if (Pmode == DImode)
     code = ((GET_CODE (addr) == ZERO_EXTEND
          || GET_CODE (addr) == AND)
         ? 'l'
--

[Bug target/52530] [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52530

Uros Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|REOPENED                    |ASSIGNED

--- Comment #7 from Uros Bizjak <ubizjak at gmail dot com> 2012-03-09 16:50:12 UTC ---
(In reply to comment #6)
> This patch works for me:
> 
> ---
> diff --git a/gcc/ChangeLog.addr32 b/gcc/ChangeLog.addr32
> index 066f1ec..a191e47 100644
> --- a/gcc/ChangeLog.addr32
> +++ b/gcc/ChangeLog.addr32
> @@ -1,3 +1,8 @@
> +2012-03-08  H.J. Lu  <hongjiu.lu@intel.com>
> +
> +    * config/i386/i386.c (ix86_print_operand_address): Only handle
> +    zero-extended DImode addresses if Pmode == DImode.
> +
>  2012-03-06  Uros Bizjak  <ubizjak@gmail.com>
> 
>      * config/i386/i386.md (*zero_extendsidi2_rex64): Allow loading
> diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
> index 69cb6ae..c2cad5a 100644
> --- a/gcc/config/i386/i386.c
> +++ b/gcc/config/i386/i386.c
> @@ -14548,7 +14548,7 @@ ix86_print_operand_address (FILE *file, rtx addr)
> 
>        /* Print SImode registers for zero-extended addresses to force
>       addr32 prefix.  Otherwise print DImode registers to avoid it.  */
> -      if (TARGET_64BIT)
> +      if (Pmode == DImode)
>      code = ((GET_CODE (addr) == ZERO_EXTEND
>           || GET_CODE (addr) == AND)
>          ? 'l'
> --

You will have addr32 added to all lea(%SImode),%SImode instructions.

I have a patch in testing that emits addresses in their natural mode (SImode or
DImode), forces 'l' override for the above RTXes and 'q' for all LEA insns.

For LEAs, we introduce %E modifier that enables special handling:

+    case 'E':
+      /* Wrap address in an UNSPEC to declare special handling.  */
+      if (TARGET_64BIT)
+        x = gen_rtx_UNSPEC (DImode, gen_rtvec (1, x), UNSPEC_LEA_ADDR);
+
+      output_address (x);
+      return;

And in ix86_print_operand_address:

+  else if (GET_CODE (addr) == UNSPEC && XINT (addr, 1) == UNSPEC_LEA_ADDR)
+    {
+      gcc_assert (TARGET_64BIT);
+      ok = ix86_decompose_address (XVECEXP (addr, 0, 0), &parts);
+      code = 'q';
+    }

[Bug target/52530] [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52530

--- Comment #8 from Uros Bizjak <ubizjak at gmail dot com> 2012-03-09 17:08:13 UTC ---
Created attachment 26865
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=26865
Patch that introduces %E modifier

Patch in testing.

[Bug target/52530] [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[uros at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52530

--- Comment #9 from uros at gcc dot gnu.org 2012-03-09 18:01:56 UTC ---
Author: uros
Date: Fri Mar  9 18:01:47 2012
New Revision: 185148

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=185148
Log:
    PR target/52530
    * config/i386/i386.c (ix86_print_operand): Handle 'E' operand modifier.
    (ix86_print_operand_address): Handle UNSPEC_LEA_ADDR. Do not fallback
    to set code to 'q'.
    * config/i386/i386.md (UNSPEC_LEA_ADDR): New unspec.
    (*movdi_internal_rex64): Use %E operand modifier for lea.
    (*movsi_internal): Ditto.
    (*lea_1): Ditto.
    (*lea<mode>_2): Ditto.
    (*lea_{3,4,5,6}_zext): Ditto.
    (*tls_global_dynamic_32_gnu): Ditto.
    (*tls_global_dynamic_64): Ditto.
    (*tls_dynamic_gnu2_lea_32): Ditto.
    (*tls_dynamic_gnu2_lea_64): Ditto.
    (pro_epilogue_adjust_stack_<mode>_add): Ditto.


Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/i386/i386.c
    trunk/gcc/config/i386/i386.md

[Bug target/52530] [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[uros at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52530

--- Comment #10 from uros at gcc dot gnu.org 2012-03-11 19:48:02 UTC ---
Author: uros
Date: Sun Mar 11 19:47:58 2012
New Revision: 185201

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=185201
Log:
    PR target/52530
    * gcc.dg/torture/pr52530.c: New test.


Added:
    trunk/gcc/testsuite/gcc.dg/torture/pr52530.c
Modified:
    trunk/gcc/testsuite/ChangeLog

[Bug target/52530] [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52530

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

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

--- Comment #11 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-03-12 14:11:18 UTC ---
Fixed.

[Bug target/52530] [4.8 regression] Many 64-bit execution failures on Solaris 10/11 with Sun as

[uros at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52530

--- Comment #12 from uros at gcc dot gnu.org 2012-08-01 19:15:04 UTC ---
Author: uros
Date: Wed Aug  1 19:14:59 2012
New Revision: 190048

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=190048
Log:
    Backport from mainline
    2012-03-09  Uros Bizjak  <ubizjak@gmail.com>

    PR target/52530
    * config/i386/i386.c (ix86_print_operand): Handle 'E' operand modifier.
    (ix86_print_operand_address): Handle UNSPEC_LEA_ADDR. Do not fallback
    to set code to 'q'.
    * config/i386/i386.md (UNSPEC_LEA_ADDR): New unspec.
    (*movdi_internal_rex64): Use %E operand modifier for lea.
    (*movsi_internal): Ditto.
    (*lea_1): Ditto.
    (*lea<mode>_2): Ditto.
    (*lea_{3,4,5,6}_zext): Ditto.
    (*tls_global_dynamic_32_gnu): Ditto.
    (*tls_global_dynamic_64): Ditto.
    (*tls_dynamic_gnu2_lea_32): Ditto.
    (*tls_dynamic_gnu2_lea_64): Ditto.
    (pro_epilogue_adjust_stack_<mode>_add): Ditto.

testsuite/ChangeLog:

    Backport from mainline
    2012-03-11  Uros Bizjak  <ubizjak@gmail.com>

    PR target/52530
    * gcc.dg/torture/pr52530.c: New test.


Added:
    branches/gcc-4_7-branch/gcc/testsuite/gcc.dg/pr52530.c
Modified:
    branches/gcc-4_7-branch/gcc/ChangeLog
    branches/gcc-4_7-branch/gcc/config/i386/i386.c
    branches/gcc-4_7-branch/gcc/config/i386/i386.md
    branches/gcc-4_7-branch/gcc/testsuite/ChangeLog