Mesa (master): i965: Make the precompile ignore DEPTH_TEXTURE_MODE on Gen7.5+.

[Kenneth Graunke]

Module: Mesa
Branch: master
Commit: 0b98b2bf535d6e6b6b02c0d47ea03f98adf42f15
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=0b98b2bf535d6e6b6b02c0d47ea03f98adf42f15

Author: Kenneth Graunke <kenneth at whitecape.org>
Date:   Wed Dec 31 18:06:41 2014 -0800

i965: Make the precompile ignore DEPTH_TEXTURE_MODE on Gen7.5+.

Gen7.5+ platforms that support the "Shader Channel Select" feature leave
key->tex.swizzles[i] as SWIZZLE_NOOP except when GL_DEPTH_TEXTURE_MODE
is GL_ALPHA (which is really uncommon).  So, the precompile should leave
them as SWIZZLE_NOOP (aka SWIZZLE_XYZW) as well.

We didn't notice this because prog->ShadowSamplers is not set correctly.
The next patch will fix that problem.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=87886
Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
Reviewed-by: Matt Turner <mattst88 at gmail.com>
Reviewed-by: Chris Forbes <chrisf at ijw.co.nz>

---

 src/mesa/drivers/dri/i965/brw_fs.cpp   |    3 ++-
 src/mesa/drivers/dri/i965/brw_vec4.cpp |    4 +++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
index d46eca1..8c7d780 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
@@ -3912,9 +3912,10 @@ brw_fs_precompile(struct gl_context *ctx,
                                          BRW_FS_VARYING_INPUT_MASK) > 16)
       key.input_slots_valid = fp->Base.InputsRead | VARYING_BIT_POS;
 
+   const bool has_shader_channel_select = brw->is_haswell || brw->gen >= 8;
    unsigned sampler_count = _mesa_fls(fp->Base.SamplersUsed);
    for (unsigned i = 0; i < sampler_count; i++) {
-      if (fp->Base.ShadowSamplers & (1 << i)) {
+      if (!has_shader_channel_select && (fp->Base.ShadowSamplers & (1 << i))) {
          /* Assume DEPTH_TEXTURE_MODE is the default: X, X, X, 1 */
          key.tex.swizzles[i] =
             MAKE_SWIZZLE4(SWIZZLE_X, SWIZZLE_X, SWIZZLE_X, SWIZZLE_ONE);
diff --git a/src/mesa/drivers/dri/i965/brw_vec4.cpp b/src/mesa/drivers/dri/i965/brw_vec4.cpp
index 4f10bdb..c96bd84 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4.cpp
@@ -1949,11 +1949,13 @@ brw_vue_setup_prog_key_for_precompile(struct gl_context *ctx,
                                       struct brw_vue_prog_key *key,
                                       GLuint id, struct gl_program *prog)
 {
+   struct brw_context *brw = brw_context(ctx);
    key->program_string_id = id;
 
+   const bool has_shader_channel_select = brw->is_haswell || brw->gen >= 8;
    unsigned sampler_count = _mesa_fls(prog->SamplersUsed);
    for (unsigned i = 0; i < sampler_count; i++) {
-      if (prog->ShadowSamplers & (1 << i)) {
+      if (!has_shader_channel_select && (prog->ShadowSamplers & (1 << i))) {
          /* Assume DEPTH_TEXTURE_MODE is the default: X, X, X, 1 */
          key->tex.swizzles[i] =
             MAKE_SWIZZLE4(SWIZZLE_X, SWIZZLE_X, SWIZZLE_X, SWIZZLE_ONE);