i965/fs: Define logical texture sampling opcodes.

Each logical variant is largely equivalent to the original opcode but
instead of taking a single payload source it expects the arguments
separately as individual sources, like:

 tex_logical dst, coordinates, shadow_c, lod, lod2,
                  sample_index, mcs, sampler, offset,
                  num_coordinate_components, num_grad_components

This patch defines the opcodes and usual instruction boilerplate,
including a placeholder lowering function provided mostly as
documentation for their source registers.

Reviewed-by: Jason Ekstrand <[email protected]>
Reviewed-by: Kenneth Graunke <[email protected]>

3 files changed, 148 insertions, 0 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_defines.h b/src/mesa/drivers/dri/i965/brw_defines.h
index 2af7413d993..373d6b8f8ab 100644
--- a/src/mesa/drivers/dri/i965/brw_defines.h
+++ b/src/mesa/drivers/dri/i965/brw_defines.h
@@ -903,18 +903,49 @@ enum opcode {
    SHADER_OPCODE_SIN,
    SHADER_OPCODE_COS,
 
+   /**
+    * Texture sampling opcodes.
+    *
+    * LOGICAL opcodes are eventually translated to the matching non-LOGICAL
+    * opcode but instead of taking a single payload blob they expect their
+    * arguments separately as individual sources:
+    *
+    * Source 0: [optional] Texture coordinates.
+    * Source 1: [optional] Shadow comparitor.
+    * Source 2: [optional] dPdx if the operation takes explicit derivatives,
+    *                      otherwise LOD value.
+    * Source 3: [optional] dPdy if the operation takes explicit derivatives.
+    * Source 4: [optional] Sample index.
+    * Source 5: [optional] MCS data.
+    * Source 6: [required] Texture sampler.
+    * Source 7: [optional] Texel offset.
+    * Source 8: [required] Number of coordinate components (as UD immediate).
+    * Source 9: [required] Number derivative components (as UD immediate).
+    */
    SHADER_OPCODE_TEX,
+   SHADER_OPCODE_TEX_LOGICAL,
    SHADER_OPCODE_TXD,
+   SHADER_OPCODE_TXD_LOGICAL,
    SHADER_OPCODE_TXF,
+   SHADER_OPCODE_TXF_LOGICAL,
    SHADER_OPCODE_TXL,
+   SHADER_OPCODE_TXL_LOGICAL,
    SHADER_OPCODE_TXS,
+   SHADER_OPCODE_TXS_LOGICAL,
    FS_OPCODE_TXB,
+   FS_OPCODE_TXB_LOGICAL,
    SHADER_OPCODE_TXF_CMS,
+   SHADER_OPCODE_TXF_CMS_LOGICAL,
    SHADER_OPCODE_TXF_UMS,
+   SHADER_OPCODE_TXF_UMS_LOGICAL,
    SHADER_OPCODE_TXF_MCS,
+   SHADER_OPCODE_TXF_MCS_LOGICAL,
    SHADER_OPCODE_LOD,
+   SHADER_OPCODE_LOD_LOGICAL,
    SHADER_OPCODE_TG4,
+   SHADER_OPCODE_TG4_LOGICAL,
    SHADER_OPCODE_TG4_OFFSET,
+   SHADER_OPCODE_TG4_OFFSET_LOGICAL,
 
    /**
     * Combines multiple sources of size 1 into a larger virtual GRF.
diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
index 936f0d19706..d9096f1b4cf 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
@@ -686,6 +686,31 @@ fs_inst::components_read(unsigned i) const
       else
          return 1;
 
+   case SHADER_OPCODE_TEX_LOGICAL:
+   case SHADER_OPCODE_TXD_LOGICAL:
+   case SHADER_OPCODE_TXF_LOGICAL:
+   case SHADER_OPCODE_TXL_LOGICAL:
+   case SHADER_OPCODE_TXS_LOGICAL:
+   case FS_OPCODE_TXB_LOGICAL:
+   case SHADER_OPCODE_TXF_CMS_LOGICAL:
+   case SHADER_OPCODE_TXF_UMS_LOGICAL:
+   case SHADER_OPCODE_TXF_MCS_LOGICAL:
+   case SHADER_OPCODE_LOD_LOGICAL:
+   case SHADER_OPCODE_TG4_LOGICAL:
+   case SHADER_OPCODE_TG4_OFFSET_LOGICAL:
+      assert(src[8].file == IMM && src[9].file == IMM);
+      /* Texture coordinates. */
+      if (i == 0)
+         return src[8].fixed_hw_reg.dw1.ud;
+      /* Texture derivatives. */
+      else if ((i == 2 || i == 3) && opcode == SHADER_OPCODE_TXD_LOGICAL)
+         return src[9].fixed_hw_reg.dw1.ud;
+      /* Texture offset. */
+      else if (i == 7)
+         return 2;
+      else
+         return 1;
+
    default:
       return 1;
    }
@@ -3361,6 +3386,25 @@ lower_fb_write_logical_send(const fs_builder &bld, fs_inst *inst,
    inst->header_size = header_size;
 }
 
+static void
+lower_sampler_logical_send(const fs_builder &bld, fs_inst *inst, opcode op)
+{
+   const brw_device_info *devinfo = bld.shader->devinfo;
+   const fs_reg &coordinate = inst->src[0];
+   const fs_reg &shadow_c = inst->src[1];
+   const fs_reg &lod = inst->src[2];
+   const fs_reg &lod2 = inst->src[3];
+   const fs_reg &sample_index = inst->src[4];
+   const fs_reg &mcs = inst->src[5];
+   const fs_reg &sampler = inst->src[6];
+   const fs_reg &offset_value = inst->src[7];
+   assert(inst->src[8].file == IMM && inst->src[9].file == IMM);
+   const unsigned coord_components = inst->src[8].fixed_hw_reg.dw1.ud;
+   const unsigned grad_components = inst->src[9].fixed_hw_reg.dw1.ud;
+
+   assert(!"Not implemented");
+}
+
 bool
 fs_visitor::lower_logical_sends()
 {
@@ -3380,6 +3424,54 @@ fs_visitor::lower_logical_sends()
                                      payload);
          break;
 
+      case SHADER_OPCODE_TEX_LOGICAL:
+         lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TEX);
+         break;
+
+      case SHADER_OPCODE_TXD_LOGICAL:
+         lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXD);
+         break;
+
+      case SHADER_OPCODE_TXF_LOGICAL:
+         lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXF);
+         break;
+
+      case SHADER_OPCODE_TXL_LOGICAL:
+         lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXL);
+         break;
+
+      case SHADER_OPCODE_TXS_LOGICAL:
+         lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXS);
+         break;
+
+      case FS_OPCODE_TXB_LOGICAL:
+         lower_sampler_logical_send(ibld, inst, FS_OPCODE_TXB);
+         break;
+
+      case SHADER_OPCODE_TXF_CMS_LOGICAL:
+         lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXF_CMS);
+         break;
+
+      case SHADER_OPCODE_TXF_UMS_LOGICAL:
+         lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXF_UMS);
+         break;
+
+      case SHADER_OPCODE_TXF_MCS_LOGICAL:
+         lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TXF_MCS);
+         break;
+
+      case SHADER_OPCODE_LOD_LOGICAL:
+         lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_LOD);
+         break;
+
+      case SHADER_OPCODE_TG4_LOGICAL:
+         lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TG4);
+         break;
+
+      case SHADER_OPCODE_TG4_OFFSET_LOGICAL:
+         lower_sampler_logical_send(ibld, inst, SHADER_OPCODE_TG4_OFFSET);
+         break;
+
       default:
          continue;
       }
diff --git a/src/mesa/drivers/dri/i965/brw_shader.cpp b/src/mesa/drivers/dri/i965/brw_shader.cpp
index 1e660d71cfc..9e3a9740d74 100644
--- a/src/mesa/drivers/dri/i965/brw_shader.cpp
+++ b/src/mesa/drivers/dri/i965/brw_shader.cpp
@@ -567,28 +567,53 @@ brw_instruction_name(enum opcode op)
 
    case SHADER_OPCODE_TEX:
       return "tex";
+   case SHADER_OPCODE_TEX_LOGICAL:
+      return "tex_logical";
    case SHADER_OPCODE_TXD:
       return "txd";
+   case SHADER_OPCODE_TXD_LOGICAL:
+      return "txd_logical";
    case SHADER_OPCODE_TXF:
       return "txf";
+   case SHADER_OPCODE_TXF_LOGICAL:
+      return "txf_logical";
    case SHADER_OPCODE_TXL:
       return "txl";
+   case SHADER_OPCODE_TXL_LOGICAL:
+      return "txl_logical";
    case SHADER_OPCODE_TXS:
       return "txs";
+   case SHADER_OPCODE_TXS_LOGICAL:
+      return "txs_logical";
    case FS_OPCODE_TXB:
       return "txb";
+   case FS_OPCODE_TXB_LOGICAL:
+      return "txb_logical";
    case SHADER_OPCODE_TXF_CMS:
       return "txf_cms";
+   case SHADER_OPCODE_TXF_CMS_LOGICAL:
+      return "txf_cms_logical";
    case SHADER_OPCODE_TXF_UMS:
       return "txf_ums";
+   case SHADER_OPCODE_TXF_UMS_LOGICAL:
+      return "txf_ums_logical";
    case SHADER_OPCODE_TXF_MCS:
       return "txf_mcs";
+   case SHADER_OPCODE_TXF_MCS_LOGICAL:
+      return "txf_mcs_logical";
    case SHADER_OPCODE_LOD:
       return "lod";
+   case SHADER_OPCODE_LOD_LOGICAL:
+      return "lod_logical";
    case SHADER_OPCODE_TG4:
       return "tg4";
+   case SHADER_OPCODE_TG4_LOGICAL:
+      return "tg4_logical";
    case SHADER_OPCODE_TG4_OFFSET:
       return "tg4_offset";
+   case SHADER_OPCODE_TG4_OFFSET_LOGICAL:
+      return "tg4_offset_logical";
+
    case SHADER_OPCODE_SHADER_TIME_ADD:
       return "shader_time_add";