Re: ICE with MEM_REF when Pmode is different from word_mode

[Richard Guenther <richard dot guenther at gmail dot com>]

On Tue, May 29, 2012 at 1:57 PM, Mohamed Shafi <shafitvm@gmail.com> wrote:
> Hi,
>
> I am porting a private target in GCC 4.6.3 version. For my target
> pointer size is 24bits and word size is 32bits. Moreover a byte is
> 32bit
>
> For the testcase gcc.c-torture/compile/921111-1.c i get the following ICE
>
> 921111-1.c: In function 'f':
> 921111-1.c:18:5: internal compiler error: in size_binop_loc, at
> fold-const.c:1436
> Please submit a full bug report,
> with preprocessed source if appropriate.
> See <http://gcc.gnu.org/bugs.html> for instructions
>
> This is the reduced testcase of the same
>
> ?struct vp {
> ?int wa;
> };
>
> typedef struct vp *vpt;
>
> typedef struct vc {
> ?int o;
> ?vpt py[8];
> } *vct;
>
> typedef struct np *npt;
> struct np {
> ?vct d;
> ?int di;
> };
>
> int f(npt dp)
> {
> ?vpt *py;
>
> ?py = &dp->d->py[dp->di];
> ?return (int)(py[1])->wa;
> }
>
> The ICE happens in tree_slp_vectorizer pass. The following is the tree
> dump just before that
>
> ;; Function f (f)
>
> f (struct np * dp)
> {
> ?struct vp * D.1232;
> ?int D.1230;
> ?unsigned int D.1228;
> ?int D.1227;
> ?struct vc * D.1225;
>
> <bb 2>:
> ?D.1225_2 = dp_1(D)->d;
> ?D.1227_4 = dp_1(D)->di;
> ?D.1228_5 = (unsigned int) D.1227_4;
> ?D.1232_9 = MEM[(struct vp * *)D.1225_2 + 4B].py[D.1228_5]{lb: 0 sz: 4};
> ?D.1230_10 = D.1232_9->wa;
> ?return D.1230_10;
> }
>
> The ICE happens for
>
> ?D.1232_9 = MEM[(struct vp * *)D.1225_2 + 4B].py[D.1228_5]{lb: 0 sz: 4};
>
> This is due to the addition of the new code in tree-data-ref.c (this
> is was not there in 4.5 series)
>
> ?if (TREE_CODE (base) == MEM_REF)
> ? ?{
> ? ? ?if (!integer_zerop (TREE_OPERAND (base, 1)))
> ? ? ? ?{
> ? ? ? ? ?if (!poffset)
> ? ? ? ? ? ?{
> ? ? ? ? ? ? ?double_int moff = mem_ref_offset (base);
> ? ? ? ? ? ? ?poffset = double_int_to_tree (sizetype, moff);
> ? ? ? ? ? ?}
> ? ? ? ? ?else
> ? ? ? ? ? ?poffset = size_binop (PLUS_EXPR, poffset, TREE_OPERAND (base, 1));

This should use mem_ref_offset, too.

> ? ? ? ?}
> ? ? ?base = TREE_OPERAND (base, 0);
> ? ?}
> ?else
> ? ?base = build_fold_addr_expr (base);
>
> the assert check in size_binop fails
>
>
> ?gcc_assert (int_binop_types_match_p (code, TREE_TYPE (arg0),
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? TREE_TYPE (arg1)));
>
> This is because the mode of arg0 and arg1 are different, one is Pmode
> and other is word_mode.
> This is present in m32c target which also has different Pmode and word_mode.
> Is this a know failure? I cannot find a bug entry for this issue.
> Should i report this?
>
> Regards,
> Shafi