[Bug c/12329] New: x86: local function declared with attribute((regparm(3))) gets corrupted parent frame pointer

[Bug c/12329] New: x86: local function declared with attribute((regparm(3))) gets corrupted parent frame pointer

[jbeulich at novell dot com]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12329

           Summary: x86: local function declared with
                    attribute((regparm(3))) gets corrupted parent frame
                    pointer
           Product: gcc
           Version: 3.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jbeulich at novell dot com
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu

Since the parent function's frame pointer is passed in ECX, that register should
not be available for argument passing. However, the third parameter is assigned
to ECX, and thus the callee's assumption of (also) finding the frame pointer
there breaks.

int test(int i) {
	static int __attribute__((__regparm__(3))) stest(int j, int k, int l) {
		return i + j + k + l;
	}
	return stest(i, i, i) * i;
}

[Bug c/12329] x86: local function declared with attribute((regparm(3))) gets corrupted parent frame pointer

[pinskia at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12329


pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code

[Bug target/12329] x86: local function declared with attribute((regparm(3))) gets corrupted parent frame pointer

[pinskia at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12329


pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|c                           |target

[Bug target/12329] x86: local function declared with attribute((regparm(3))) gets corrupted parent frame pointer

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-04-27 18:09 -------
Confirmed.
It is easier to see on the tree-ssa:
(insn 5 4 6 (set (reg/v:SI 61 [ l ])
        (reg:SI 2 cx [ l ])) -1 (nil)
    (nil))

(insn 6 5 7 (set (reg/f:SI 62 [ CHAIN.6 ])
        (reg:SI 2 cx)) -1 (nil)
    (nil))

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
      Known to fail|                            |2.95.3 3.0.4
   Last reconfirmed|0000-00-00 00:00:00         |2004-04-27 18:09:53
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12329

[Bug target/12329] x86: local function declared with attribute((regparm(3))) gets corrupted parent frame pointer

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-07-27 02:51 -------
Basically we should reject attribute((regparm(3))) on nested functions.
Note we already do not put attribute((regparm(3))) on nested functions automatically:
      /* Use register calling convention for local functions when possible.  */
      if (!TARGET_64BIT && !user_convention && decl
          && flag_unit_at_a_time && !profile_flag)
        {
          struct cgraph_local_info *i = cgraph_local_info (decl);
          if (i && i->local)
            {
              /* We can't use regparm(3) for nested functions as these use
                 static chain pointer in third argument.  */
              if (DECL_CONTEXT (decl) && !DECL_NO_STATIC_CHAIN (decl))
                regparm = 2;
              else
                regparm = 3;
            }
        }

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12329

[Bug target/12329] x86: local function declared with attribute((regparm(3))) gets corrupted parent frame pointer

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |accepts-invalid
   Last reconfirmed|2005-04-27 00:31:11         |2005-07-23 05:53:30
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12329

[Bug target/12329] x86: local function declared with attribute((regparm(3))) gets corrupted parent frame pointer

[ubizjak at gmail dot com]

------- Comment #6 from ubizjak at gmail dot com  2008-04-06 06:43 -------
Fixed for 4.4.0.


-- 

ubizjak at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12329

[Bug target/12329] x86: local function declared with attribute((regparm(3))) gets corrupted parent frame pointer

[uros at gcc dot gnu dot org]

------- Comment #5 from uros at gcc dot gnu dot org  2008-04-06 06:41 -------
Subject: Bug 12329

Author: uros
Date: Sun Apr  6 06:40:47 2008
New Revision: 133954

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=133954
Log:
        PR target/12329
        * config/i386/i386.c (ix86_function_regparm): Error if regparm(3)
        attribute is used for nested functions.

testsuite/ChangeLog:

        PR target/12329
        * gcc.target/i386/pr12329.c: New test.


Added:
    trunk/gcc/testsuite/gcc.target/i386/pr12329.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/i386/i386.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12329

[Bug target/12329] x86: local function declared with attribute((regparm(3))) gets corrupted parent frame pointer

[ubizjak at gmail dot com]

------- Comment #4 from ubizjak at gmail dot com  2008-03-22 19:51 -------
(In reply to comment #3)
> Subject: Bug 12329
> 
> Author: hjl
> Date: Sat Mar 22 16:03:57 2008
> New Revision: 133448

According to [1], it is not good to silently change number of passing arguments
for a declared regparm(X) function.

[1] http://gcc.gnu.org/ml/gcc-patches/2008-03/msg01310.html


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12329

[Bug target/12329] x86: local function declared with attribute((regparm(3))) gets corrupted parent frame pointer

[hjl at gcc dot gnu dot org]

------- Comment #3 from hjl at gcc dot gnu dot org  2008-03-22 16:04 -------
Subject: Bug 12329

Author: hjl
Date: Sat Mar 22 16:03:57 2008
New Revision: 133448

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=133448
Log:
gcc/

2008-03-22  Uros Bizjak  <ubizjak@gmail.com>
            H.J. Lu  <hongjiu.lu@intel.com>

        PR target/12329
        * config/i386/i386.c (ix86_function_regparm): Limit the number of
        register passing arguments to 2 for nested functions.

gcc/testsuite/

2008-03-22  Uros Bizjak  <ubizjak@gmail.com>

        PR target/12329
        * gcc.target/i386/pr12329.c: New test.

Added:
    branches/stack/gcc/testsuite/gcc.target/i386/pr12329.c
Modified:
    branches/stack/gcc/ChangeLog.stackalign
    branches/stack/gcc/config/i386/i386.c
    branches/stack/gcc/testsuite/ChangeLog.stackalign


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12329