[Bug lto/63607] New: run fail with -flto -mfloat-abi=softfp for armeb-linux-gnueabi-gcc

[Bug lto/63607] New: run fail with -flto -mfloat-abi=softfp for armeb-linux-gnueabi-gcc

[fei.yang0953 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63607

            Bug ID: 63607
           Summary: run fail with -flto -mfloat-abi=softfp for
                    armeb-linux-gnueabi-gcc
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
          Assignee: unassigned at gcc dot gnu.org
          Reporter: fei.yang0953 at gmail dot com

testsuite/gcc.dg/torture/stackalign/builtin-apply-4.c:

/* PR tree-optimization/20076 */
/* { dg-do run } */

extern void abort (void);

double
foo (int arg)
{
  if (arg != 116)
    abort();
  return arg + 1;
}

inline double
bar (int arg)
{
  foo (arg);
  __builtin_return (__builtin_apply ((void (*) ()) foo,
                                     __builtin_apply_args (), 16));
}

int
main (int argc, char **argv)
{
  if (bar (116) != 117.0)
    abort ();

  return 0;
}

Compile option: armeb-linux-gnueabi-gcc builtin-apply-4.c -static
-mfloat-abi=softfp -flto 

Disassembly:
0000076c <main>:
76c:  e92d4800     push   {fp, lr}
770:  e28db004     add    fp, sp, #4
774:  e3a02113     mov    r2, #-1073741820    ; 0xc0000004
778:  e30a3aaa     movw   r3, #43690   ; 0xaaaa
77c:  e34a3aaa     movt   r3, #43690   ; 0xaaaa
780:  e5823000     str    r3, [r2]
784:  e3a00074     mov    r0, #116     ; 0x74
788:  ebffffaa     bl     638 <bar.4066>
78c: eeb06b40    vmov.f64    d6, d0
790:  ed9f7b0a     vldr   d7, [pc, #40] ; 7c0 <main+0x54>
794:  eeb46b47     vcmp.f64     d6, d7

Analysis: Return value is not passed correctly. As we can see from line 790,
main gets the return value from d0 register, which is wrong as we use
-mfloat-abi=softfp here.

[Bug lto/63607] run fail with -flto -mfloat-abi=softfp for armeb-linux-gnueabi-gcc

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63607

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

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

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Is -mfloat-abi=softfp properly used at LTO stage?

[Bug lto/63607] run fail with -flto -mfloat-abi=softfp for armeb-linux-gnueabi-gcc

[fei.yang0953 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63607

--- Comment #2 from Fei Yang <fei.yang0953 at gmail dot com> ---
(In reply to Richard Biener from comment #1)
> Is -mfloat-abi=softfp properly used at LTO stage?

It seems that -mfloat-abi=softfp is here for lto1:


/home/lxr/install/bin/../lib/gcc/../../libexec/gcc/armeb-linux-gnueabi/4.7.1/lto1
-quiet -dumpdir ./ -dumpbase 1.wpa -mfloat-abi=softfp -march=armv7-a
-mtls-dialect=gnu -mfloat-abi=softfp -march=armv7-a -mtls-dialect=gnu -auxbase
cc9cih7t -O2 -version -fltrans-output-list=/tmp/ccZqlDqA.ltrans.out -fwpa
-fresolution=/tmp/ccUnDlh3.res @/tmp/ccSi9hcz

[Bug lto/63607] run fail with -flto -mfloat-abi=softfp for armeb-linux-gnueabi-gcc

[ramana at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63607

Ramana Radhakrishnan <ramana at gcc dot gnu.org> changed:

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

--- Comment #3 from Ramana Radhakrishnan <ramana at gcc dot gnu.org> ---
(In reply to Fei Yang from comment #2)
> (In reply to Richard Biener from comment #1)
> > Is -mfloat-abi=softfp properly used at LTO stage?
> 
> It seems that -mfloat-abi=softfp is here for lto1:
> 
>  /home/lxr/install/bin/../lib/gcc/../../libexec/gcc/armeb-linux-gnueabi/4.7.
> 1/lto1 -quiet -dumpdir ./ -dumpbase 1.wpa -mfloat-abi=softfp -march=armv7-a
> -mtls-dialect=gnu -mfloat-abi=softfp -march=armv7-a -mtls-dialect=gnu
> -auxbase cc9cih7t -O2 -version -fltrans-output-list=/tmp/ccZqlDqA.ltrans.out
> -fwpa -fresolution=/tmp/ccUnDlh3.res @/tmp/ccSi9hcz

Can you check if it occurs with 4.8 , 4.9 or trunk today ? I don't really have
a big endian environment setup to reproduce this easily enough.

[Bug lto/63607] run fail with -flto -mfloat-abi=softfp for armeb-linux-gnueabi-gcc

[ramana at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63607

Ramana Radhakrishnan <ramana at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P4
             Status|UNCONFIRMED                 |WAITING
   Last reconfirmed|                            |2015-02-12
     Ever confirmed|0                           |1

--- Comment #4 from Ramana Radhakrishnan <ramana at gcc dot gnu.org> ---
Even if confirmed this is BE related and so pushing this down to P4.