isl: tag unreachable path as such

GCC should be able to figure out that all the possible enum values are
exhausted in the switch() and all the branches return from the function,
but apparently it doesn't, so let's tell the compiler explicitly.

This gets rid of the following warnings in GCC 9:

    [1/24] Compiling C object 'src/intel/isl/60d23f8@@isl@sta/isl.c.o'.
    ../src/intel/isl/isl.c: In function ‘isl_surf_init_s’:
    ../src/intel/isl/isl.c:1569:10: warning: ‘array_pitch_el_rows’ may be used uninitialized in this function [-Wmaybe-uninitialized]
     1569 |    *surf = (struct isl_surf) {
          |    ~~~~~~^~~~~~~~~~~~~~~~~~~~~
     1570 |       .dim = info->dim,
          |       ~~~~~~~~~~~~~~~~~
     1571 |       .dim_layout = dim_layout,
          |       ~~~~~~~~~~~~~~~~~~~~~~~~~
     1572 |       .msaa_layout = msaa_layout,
          |       ~~~~~~~~~~~~~~~~~~~~~~~~~~~
     1573 |       .tiling = tiling,
          |       ~~~~~~~~~~~~~~~~~
     1574 |       .format = info->format,
          |       ~~~~~~~~~~~~~~~~~~~~~~~
     1575 |
          |
     1576 |       .levels = info->levels,
          |       ~~~~~~~~~~~~~~~~~~~~~~~
     1577 |       .samples = info->samples,
          |       ~~~~~~~~~~~~~~~~~~~~~~~~~
     1578 |
          |
     1579 |       .image_alignment_el = image_align_el,
          |       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     1580 |       .logical_level0_px = logical_level0_px,
          |       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     1581 |       .phys_level0_sa = phys_level0_sa,
          |       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     1582 |
          |
     1583 |       .size_B = size_B,
          |       ~~~~~~~~~~~~~~~~~
     1584 |       .alignment_B = base_alignment_B,
          |       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     1585 |       .row_pitch_B = row_pitch_B,
          |       ~~~~~~~~~~~~~~~~~~~~~~~~~~~
     1586 |       .array_pitch_el_rows = array_pitch_el_rows,
          |       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     1587 |       .array_pitch_span = array_pitch_span,
          |       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     1588 |
          |
     1589 |       .usage = info->usage,
          |       ~~~~~~~~~~~~~~~~~~~~~
     1590 |    };
          |    ~
    ../src/intel/isl/isl.c:1488:24: warning: ‘*((void *)&phys_total_el+4)’ may be used uninitialized in this function [-Wmaybe-uninitialized]
     1488 |    struct isl_extent2d phys_total_el;
          |                        ^~~~~~~~~~~~~
    ../src/intel/isl/isl.c:1335:38: warning: ‘phys_total_el’ may be used uninitialized in this function [-Wmaybe-uninitialized]
     1335 |       isl_align_div(phys_total_el->w * tile_el_scale,
          |                     ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~
    ../src/intel/isl/isl.c:1488:24: note: ‘phys_total_el’ was declared here
     1488 |    struct isl_extent2d phys_total_el;
          |                        ^~~~~~~~~~~~~

Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

diff --git a/src/intel/isl/isl.c b/src/intel/isl/isl.c
index 2e33031cbbf7f00e2d7226e211bec412ad267375..43ad8561c7e796a7812d0a8190a04c3d7be456fe 100644 (file)
--- a/src/intel/isl/isl.c
+++ b/src/intel/isl/isl.c
@@ -1270,6 +1270,8 @@ isl_calc_phys_total_extent_el(const struct isl_device *dev,
                                             total_extent_el);
       return;
    }
+
+   unreachable("invalid value for dim_layout");
 }
 
 static uint32_t