i965: Fix textureSize() depth value for 1 layer surfaces on Gen4-6.

According to the Sandybridge PRM's description of the resinfo message,
the .z value returned will be Depth == 0 ? 0 : Depth + 1.  The earlier
PRMs have the same table.

This means we return 0 for array textures with a single slice, when
we ought to return 1.  Just override it to max(depth, 1).

Fixes 10 dEQP-GLES3.functional tests on Sandybridge:
shaders.texture_functions.texturesize.sampler2darray_fixed_vertex
shaders.texture_functions.texturesize.sampler2darray_fixed_fragment
shaders.texture_functions.texturesize.sampler2darray_float_vertex
shaders.texture_functions.texturesize.sampler2darray_float_fragment
shaders.texture_functions.texturesize.isampler2darray_vertex
shaders.texture_functions.texturesize.isampler2darray_fragment
shaders.texture_functions.texturesize.usampler2darray_vertex
shaders.texture_functions.texturesize.usampler2darray_fragment
shaders.texture_functions.texturesize.sampler2darrayshadow_vertex
shaders.texture_functions.texturesize.sampler2darrayshadow_fragment

Cc: mesa-stable@lists.freedesktop.org
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>

1 files changed, 10 insertions, 4 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
index d30330a379f..2ab141fdf21 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
@@ -1056,10 +1056,16 @@ vec4_visitor::emit_texture(ir_texture_opcode op,
    /* fixup num layers (z) for cube arrays: hardware returns faces * layers;
     * spec requires layers.
     */
-   if (op == ir_txs && is_cube_array) {
-      emit_math(SHADER_OPCODE_INT_QUOTIENT,
-                writemask(inst->dst, WRITEMASK_Z),
-                src_reg(inst->dst), brw_imm_d(6));
+   if (op == ir_txs) {
+      if (is_cube_array) {
+         emit_math(SHADER_OPCODE_INT_QUOTIENT,
+                   writemask(inst->dst, WRITEMASK_Z),
+                   src_reg(inst->dst), brw_imm_d(6));
+      } else if (devinfo->gen < 7) {
+         /* Gen4-6 return 0 instead of 1 for single layer surfaces. */
+         emit_minmax(BRW_CONDITIONAL_GE, writemask(inst->dst, WRITEMASK_Z),
+                     src_reg(inst->dst), brw_imm_d(1));
+      }
    }
 
    if (devinfo->gen == 6 && op == ir_tg4) {