[Bug middle-end/39315] New: Unaligned move used on aligned stack variable

[Bug middle-end/39315] New: Unaligned move used on aligned stack variable

[hjl dot tools at gmail dot com]

[hjl@gnu-6 pr]$ cat x.c
typedef float __m128 __attribute__ ((__vector_size__ (16), __may_alias__));
extern void bar (__m128 *);
void
foo (__m128 *x)
{
  __m128 b = *x;
  bar (&b);
}
[hjl@gnu-6 pr]$ make x.s
/export/build/gnu/gcc-work/build-x86_64-linux/gcc/xgcc
-B/export/build/gnu/gcc-work/build-x86_64-linux/gcc/ -S -o x.s -O2
-fno-asynchronous-unwind-tables x.c
[hjl@gnu-6 pr]$ cat x.s
        .file   "x.c"
        .text
        .p2align 4,,15
.globl foo
        .type   foo, @function
foo:
        subq    $24, %rsp
        movaps  (%rdi), %xmm0
        movq    %rsp, %rdi
        movlps  %xmm0, (%rsp)
        movhps  %xmm0, 8(%rsp)
        call    bar
        addq    $24, %rsp
        ret

expand_one_stack_var_at has

  /* Set alignment we actually gave this decl.  */
  offset -= frame_phase;
  align = offset & -offset;
  align *= BITS_PER_UNIT;
  if (align > STACK_BOUNDARY || align == 0)
    align = STACK_BOUNDARY;
  DECL_ALIGN (decl) = align;
  DECL_USER_ALIGN (decl) = 0;

  set_mem_attributes (x, decl, true);

That is we always set alignment attribute of a stack variable
to <= STACK_BOUNDARY even if we can align it properly.  One
consequence is unaligned move is used on aligned memory.


-- 
           Summary: Unaligned move used on aligned stack variable
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: hjl dot tools at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[hjl dot tools at gmail dot com]

-- 

hjl dot tools at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[hjl dot tools at gmail dot com]

------- Comment #1 from hjl dot tools at gmail dot com  2009-02-26 17:01 -------
Gcc 4.3 generates aligned move since it doesn't check the
alignment attribute.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[hjl dot tools at gmail dot com]

------- Comment #2 from hjl dot tools at gmail dot com  2009-02-26 17:13 -------
Created an attachment (id=17368)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=17368&action=view)
A patch

Does this patch make sense?


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[Joey dot ye at intel dot com]

------- Comment #3 from Joey dot ye at intel dot com  2009-02-27 02:53 -------
(In reply to comment #2)
> Created an attachment (id=17368)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=17368&action=view) [edit]
> A patch
> Does this patch make sense?
It works fine.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[hjl dot tools at gmail dot com]

------- Comment #4 from hjl dot tools at gmail dot com  2009-02-27 03:37 -------
(In reply to comment #3)
> (In reply to comment #2)
> > Created an attachment (id=17368)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=17368&action=view) [edit]
> > A patch
> > Does this patch make sense?
> It works fine.
> 

It failed for me in libgcc during bootstrap on Linux/ia32.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[hjl dot tools at gmail dot com]

------- Comment #5 from hjl dot tools at gmail dot com  2009-02-28 00:03 -------
Created an attachment (id=17373)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=17373&action=view)
A new patch

This patch may work better.


-- 

hjl dot tools at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #17368|0                           |1
        is obsolete|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[hjl dot tools at gmail dot com]

------- Comment #6 from hjl dot tools at gmail dot com  2009-02-28 02:03 -------
Created an attachment (id=17375)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=17375&action=view)
An updated patch

When align == 0, we should align variable to STACK_BOUNDARY.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[hjl dot tools at gmail dot com]

------- Comment #7 from hjl dot tools at gmail dot com  2009-02-28 18:41 -------
A patch is posted at

http://gcc.gnu.org/ml/gcc-patches/2009-02/msg01267.html


-- 

hjl dot tools at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                URL|                            |http://gcc.gnu.org/ml/gcc-
                   |                            |patches/2009-
                   |                            |02/msg01267.html


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[hjl at gcc dot gnu dot org]

------- Comment #8 from hjl at gcc dot gnu dot org  2009-02-28 18:55 -------
Subject: Bug 39315

Author: hjl
Date: Sat Feb 28 18:55:06 2009
New Revision: 144492

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=144492
Log:
gcc/

2009-02-28  H.J. Lu  <hongjiu.lu@intel.com>

        PR middle-end/39315
        * cfgexpand.c (expand_one_stack_var_at): Change alignment
        limit to MAX_SUPPORTED_STACK_ALIGNMENT.

gcc/testsuite/

2009-02-28  H.J. Lu  <hongjiu.lu@intel.com>

        PR middle-end/39315
        * gcc.target/i386/pr39315-1.c: New.
        * gcc.target/i386/pr39315-2.c: Likewise.
        * gcc.target/i386/pr39315-3.c: Likewise.
        * gcc.target/i386/pr39315-4.c: Likewise.
        * gcc.target/i386/pr39315-check.c: Likewise.

Added:
    branches/stack/gcc/testsuite/gcc.target/i386/pr39315-1.c
    branches/stack/gcc/testsuite/gcc.target/i386/pr39315-2.c
    branches/stack/gcc/testsuite/gcc.target/i386/pr39315-3.c
    branches/stack/gcc/testsuite/gcc.target/i386/pr39315-4.c
    branches/stack/gcc/testsuite/gcc.target/i386/pr39315-check.c
Modified:
    branches/stack/gcc/ChangeLog.stackalign
    branches/stack/gcc/cfgexpand.c
    branches/stack/gcc/testsuite/ChangeLog.stackalign


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[hjl at gcc dot gnu dot org]

------- Comment #9 from hjl at gcc dot gnu dot org  2009-03-27 22:37 -------
Subject: Bug 39315

Author: hjl
Date: Fri Mar 27 22:37:39 2009
New Revision: 145138

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=145138
Log:
gcc/

2009-03-27  H.J. Lu  <hongjiu.lu@intel.com>

        PR middle-end/39315
        * cfgexpand.c (expand_one_stack_var_at): Change alignment
        limit to MAX_SUPPORTED_STACK_ALIGNMENT.

gcc/testsuite/

2009-03-27  H.J. Lu  <hongjiu.lu@intel.com>

        PR middle-end/39315
        * gcc.target/i386/pr39315-1.c: New.
        * gcc.target/i386/pr39315-2.c: Likewise.
        * gcc.target/i386/pr39315-3.c: Likewise.
        * gcc.target/i386/pr39315-4.c: Likewise.
        * gcc.target/i386/pr39315-check.c: Likewise.

Added:
    trunk/gcc/testsuite/gcc.target/i386/pr39315-1.c
    trunk/gcc/testsuite/gcc.target/i386/pr39315-2.c
    trunk/gcc/testsuite/gcc.target/i386/pr39315-3.c
    trunk/gcc/testsuite/gcc.target/i386/pr39315-4.c
    trunk/gcc/testsuite/gcc.target/i386/pr39315-check.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/cfgexpand.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[pinskia at gcc dot gnu dot org]

------- Comment #10 from pinskia at gcc dot gnu dot org  2009-04-16 18:33 -------
Stop setting the target milestone unless it is a regression.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.5.0                       |---


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[hjl dot tools at gmail dot com]

------- Comment #11 from hjl dot tools at gmail dot com  2009-07-23 13:43 -------
*** Bug 40838 has been marked as a duplicate of this bug. ***


-- 

hjl dot tools at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |mikulas at artax dot karlin
                   |                            |dot mff dot cuni dot cz


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[hjl at gcc dot gnu dot org]

------- Comment #12 from hjl at gcc dot gnu dot org  2009-10-31 16:58 -------
Subject: Bug 39315

Author: hjl
Date: Sat Oct 31 16:58:17 2009
New Revision: 153780

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=153780
Log:
gcc/

2009-10-31  H.J. Lu  <hongjiu.lu@intel.com>

        Backport from mainline:
        2009-03-27  H.J. Lu  <hongjiu.lu@intel.com>

        PR middle-end/39315
        * cfgexpand.c (expand_one_stack_var_at): Change alignment
        limit to MAX_SUPPORTED_STACK_ALIGNMENT.

gcc/testsuite/

2009-10-31  H.J. Lu  <hongjiu.lu@intel.com>

        Backport from mainline:
        2009-03-27  H.J. Lu  <hongjiu.lu@intel.com>

        PR middle-end/39315
        * gcc.target/i386/pr39315-1.c: New.
        * gcc.target/i386/pr39315-2.c: Likewise.
        * gcc.target/i386/pr39315-3.c: Likewise.
        * gcc.target/i386/pr39315-4.c: Likewise.
        * gcc.target/i386/pr39315-check.c: Likewise.

Added:
    branches/ix86/gcc-4_4-branch/gcc/testsuite/gcc.target/i386/pr39315-1.c
    branches/ix86/gcc-4_4-branch/gcc/testsuite/gcc.target/i386/pr39315-2.c
    branches/ix86/gcc-4_4-branch/gcc/testsuite/gcc.target/i386/pr39315-3.c
    branches/ix86/gcc-4_4-branch/gcc/testsuite/gcc.target/i386/pr39315-4.c
    branches/ix86/gcc-4_4-branch/gcc/testsuite/gcc.target/i386/pr39315-check.c
Modified:
    branches/ix86/gcc-4_4-branch/gcc/ChangeLog.ix86
    branches/ix86/gcc-4_4-branch/gcc/cfgexpand.c
    branches/ix86/gcc-4_4-branch/gcc/testsuite/ChangeLog.ix86


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[hjl dot tools at gmail dot com]

------- Comment #13 from hjl dot tools at gmail dot com  2010-02-20 01:05 -------
*** Bug 43124 has been marked as a duplicate of this bug. ***


-- 

hjl dot tools at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |kai dot germaschewski at
                   |                            |gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315

[Bug middle-end/39315] Unaligned move used on aligned stack variable

[rguenth at gcc dot gnu dot org]

------- Comment #14 from rguenth at gcc dot gnu dot org  2010-02-20 14:08 -------
On trunk I get:

foo:
        subl    $44, %esp
        movl    48(%esp), %eax
        movaps  (%eax), %xmm0
        leal    16(%esp), %eax
        movl    %eax, (%esp)
        movaps  %xmm0, 16(%esp)
        call    bar
        addl    $44, %esp
        ret

thus, fixed.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
      Known to work|                            |4.5.0
         Resolution|                            |FIXED
   Target Milestone|---                         |4.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39315