Mesa (9.0): i965: Use Haswell' s sample_d_c for textureGrad with shadow samplers.

[Kenneth Graunke]

Module: Mesa
Branch: 9.0
Commit: d02343e5016a5795451af3e0315b658b39463a30
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=d02343e5016a5795451af3e0315b658b39463a30

Author: Kenneth Graunke <kenneth at whitecape.org>
Date:   Fri Jan  4 07:53:09 2013 -0800

i965: Use Haswell's sample_d_c for textureGrad with shadow samplers.

The new hardware actually just supports this now.

Reviewed-by: Eric Anholt <eric at anholt.net>
(cherry picked from commit 899017fc54c40c969b5239b33f3a17b311878b0d)

---

 src/mesa/drivers/dri/i965/brw_defines.h     |    1 +
 src/mesa/drivers/dri/i965/brw_fs_emit.cpp   |    9 +++++++--
 src/mesa/drivers/dri/i965/brw_shader.cpp    |    3 ++-
 src/mesa/drivers/dri/i965/brw_vec4_emit.cpp |    9 +++++++--
 4 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_defines.h b/src/mesa/drivers/dri/i965/brw_defines.h
index 6dc4707..022629e 100644
--- a/src/mesa/drivers/dri/i965/brw_defines.h
+++ b/src/mesa/drivers/dri/i965/brw_defines.h
@@ -838,6 +838,7 @@ enum brw_message_target {
 #define GEN5_SAMPLER_MESSAGE_SAMPLE_LOD_COMPARE  6
 #define GEN5_SAMPLER_MESSAGE_SAMPLE_LD           7
 #define GEN5_SAMPLER_MESSAGE_SAMPLE_RESINFO      10
+#define HSW_SAMPLER_MESSAGE_SAMPLE_DERIV_COMPARE 20
 #define GEN7_SAMPLER_MESSAGE_SAMPLE_LD_MCS       29
 #define GEN7_SAMPLER_MESSAGE_SAMPLE_LD2DMS       30
 #define GEN7_SAMPLER_MESSAGE_SAMPLE_LD2DSS       31
diff --git a/src/mesa/drivers/dri/i965/brw_fs_emit.cpp b/src/mesa/drivers/dri/i965/brw_fs_emit.cpp
index 5900c0e..09e70dc 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_emit.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_emit.cpp
@@ -312,8 +312,13 @@ fs_visitor::generate_tex(fs_inst *inst, struct brw_reg dst, struct brw_reg src)
 	 msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_RESINFO;
 	 break;
       case SHADER_OPCODE_TXD:
-	 /* There is no sample_d_c message; comparisons are done manually */
-	 msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_DERIVS;
+         if (inst->shadow_compare) {
+            /* Gen7.5+.  Otherwise, lowered by brw_lower_texture_gradients(). */
+            assert(intel->is_haswell);
+            msg_type = HSW_SAMPLER_MESSAGE_SAMPLE_DERIV_COMPARE;
+         } else {
+            msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_DERIVS;
+         }
 	 break;
       case SHADER_OPCODE_TXF:
 	 msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_LD;
diff --git a/src/mesa/drivers/dri/i965/brw_shader.cpp b/src/mesa/drivers/dri/i965/brw_shader.cpp
index 1b509c0..edb4430 100644
--- a/src/mesa/drivers/dri/i965/brw_shader.cpp
+++ b/src/mesa/drivers/dri/i965/brw_shader.cpp
@@ -132,7 +132,8 @@ brw_link_shader(struct gl_context *ctx, struct gl_shader_program *shProg)
 	 lower_if_to_cond_assign(shader->ir, 16);
 
       do_lower_texture_projection(shader->ir);
-      brw_lower_texture_gradients(shader->ir);
+      if (intel->gen < 8 && !intel->is_haswell)
+         brw_lower_texture_gradients(shader->ir);
       do_vec_index_to_cond_assign(shader->ir);
       brw_do_cubemap_normalize(shader->ir);
       lower_noise(shader->ir);
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp b/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
index 765e1d6..55bff7b 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
@@ -381,8 +381,13 @@ vec4_visitor::generate_tex(vec4_instruction *inst,
 	 }
 	 break;
       case SHADER_OPCODE_TXD:
-	 /* There is no sample_d_c message; comparisons are done manually. */
-	 msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_DERIVS;
+         if (inst->shadow_compare) {
+            /* Gen7.5+.  Otherwise, lowered by brw_lower_texture_gradients(). */
+            assert(intel->is_haswell);
+            msg_type = HSW_SAMPLER_MESSAGE_SAMPLE_DERIV_COMPARE;
+         } else {
+            msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_DERIVS;
+         }
 	 break;
       case SHADER_OPCODE_TXF:
 	 msg_type = GEN5_SAMPLER_MESSAGE_SAMPLE_LD;