[Bug jit/100242] New: libgccjit.so: error: in expmed_mode_index, at expmed.h:249

[Bug jit/100242] New: libgccjit.so: error: in expmed_mode_index, at expmed.h:249

[bouanto at zoho dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100242

            Bug ID: 100242
           Summary: libgccjit.so: error: in expmed_mode_index, at
                    expmed.h:249
           Product: gcc
           Version: 10.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: jit
          Assignee: dmalcolm at gcc dot gnu.org
          Reporter: bouanto at zoho dot com
  Target Milestone: ---

Created attachment 50664
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=50664&action=edit
First part of the compressed reproducer

Hi.
I get the following error for the attached reproducer:

during RTL pass: expand
libgccjit.so: error: in expmed_mode_index, at expmed.h:249
0x7f0da2e61a35 expmed_mode_index
        ../../../gcc/gcc/expmed.h:249
0x7f0da2e61aa4 expmed_op_cost_ptr
        ../../../gcc/gcc/expmed.h:271
0x7f0da2e620dc sdiv_cost_ptr
        ../../../gcc/gcc/expmed.h:540
0x7f0da2e62129 sdiv_cost
        ../../../gcc/gcc/expmed.h:558
0x7f0da2e73c12 expand_divmod(int, tree_code, machine_mode, rtx_def*, rtx_def*,
rtx_def*, int)
        ../../../gcc/gcc/expmed.c:4335
0x7f0da2ea1423 expand_expr_real_2(separate_ops*, rtx_def*, machine_mode,
expand_modifier)
        ../../../gcc/gcc/expr.c:9240
0x7f0da2cd1a1e expand_gimple_stmt_1
        ../../../gcc/gcc/cfgexpand.c:3796
0x7f0da2cd1c30 expand_gimple_stmt
        ../../../gcc/gcc/cfgexpand.c:3857
0x7f0da2cd90a9 expand_gimple_basic_block
        ../../../gcc/gcc/cfgexpand.c:5898
0x7f0da2cdade8 execute
        ../../../gcc/gcc/cfgexpand.c:6582

The reproducer was so big that I needed to compress it and split it in 3 files,
so you'll have to cat the 3 files together and uncompress it.

(If you could also explain to me how to find out where exactly is the issue in
the reproducer in order to make it smaller and easier to debug, I'd
appreciate.)

Thanks to fix this issue.

[Bug jit/100242] libgccjit.so: error: in expmed_mode_index, at expmed.h:249

[bouanto at zoho dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100242

--- Comment #1 from Antoni <bouanto at zoho dot com> ---
Created attachment 50665
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=50665&action=edit
Second part of the reproducer

[Bug jit/100242] libgccjit.so: error: in expmed_mode_index, at expmed.h:249

[bouanto at zoho dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100242

--- Comment #2 from Antoni <bouanto at zoho dot com> ---
Created attachment 50666
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=50666&action=edit
Third part of the reproducer

[Bug jit/100242] libgccjit.so: error: in expmed_mode_index, at expmed.h:249

[bouanto at zoho dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100242

--- Comment #3 from Antoni <bouanto at zoho dot com> ---
Created attachment 50668
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=50668&action=edit
Smaller reproducer

Ok, I figured out how to find the location of the error.

In this case, it's caused by using the modulo operation on floats.

I guess it should either be forbidden or use the `fmodf` intrinsics.

[Bug jit/100242] libgccjit.so: error: in expmed_mode_index, at expmed.h:249

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100242

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2021-05-11
                 CC|                            |marxin at gcc dot gnu.org
           Assignee|dmalcolm at gcc dot gnu.org        |marxin at gcc dot gnu.org
     Ever confirmed|0                           |1

--- Comment #4 from Martin Liška <marxin at gcc dot gnu.org> ---
I'll take a look.

[Bug jit/100242] libgccjit.so: error: in expmed_mode_index, at expmed.h:249

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100242

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|marxin at gcc dot gnu.org          |dmalcolm at gcc dot gnu.org
             Status|ASSIGNED                    |NEW
           Keywords|                            |ice-on-invalid-code

--- Comment #5 from Martin Liška <marxin at gcc dot gnu.org> ---
Also leaving to David, this one is less serious as it's invalid input.
For C FE, we report:

gcc x.c
x.c: In function ‘foo’:
x.c:3:5: error: invalid operands to binary % (have ‘float’ and ‘float’)
    3 |   a %= b;
      |     ^~