Re: ICE with MEM_REF when Pmode is different from word_mode

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

On Wed, May 30, 2012 at 4:31 PM, Mohamed Shafi <shafitvm@gmail.com> wrote:
> On 29 May 2012 17:31, Richard Guenther <richard.guenther@gmail.com> wrote:
>> 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.
>>
>
> This is present in the trunk also. Will you be submitting a patch for this?

I put it on my TODO list.  Something like

Index: gcc/tree-data-ref.c
===================================================================
--- gcc/tree-data-ref.c (revision 188008)
+++ gcc/tree-data-ref.c (working copy)
@@ -720,13 +720,12 @@ dr_analyze_innermost (struct data_refere
     {
       if (!integer_zerop (TREE_OPERAND (base, 1)))
        {
+         double_int moff = mem_ref_offset (base);
+         tree mofft = double_int_to_tree (sizetype, moff);
          if (!poffset)
-           {
-             double_int moff = mem_ref_offset (base);
-             poffset = double_int_to_tree (sizetype, moff);
-           }
+           poffset = mofft;
          else
-           poffset = size_binop (PLUS_EXPR, poffset, TREE_OPERAND (base, 1));
+           poffset = size_binop (PLUS_EXPR, poffset, mofft);
        }
       base = TREE_OPERAND (base, 0);
     }


> Shafi