[Mesa-dev] [PATCH 8/8 v2] i965: Enable EXT_shader_samples_identical

[Ian Romanick]

From: Ian Romanick <ian.d.romanick at intel.com>

v2: Handle immediate value for MCS smarter.  Rebase on changes to
nir_texop_sampels_identical (missing second parameter).  Suggested by
Jason.  This still doesn't handle the 16x MSAA case.

Signed-off-by: Ian Romanick <ian.d.romanick at intel.com>
---
 src/mesa/drivers/dri/i965/brw_fs_nir.cpp       |  4 +++-
 src/mesa/drivers/dri/i965/brw_fs_visitor.cpp   | 16 ++++++++++++++++
 src/mesa/drivers/dri/i965/brw_vec4_nir.cpp     |  4 +++-
 src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp | 11 +++++++++++
 src/mesa/drivers/dri/i965/intel_extensions.c   |  1 +
 5 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
index 80315fe..c85c9fc 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
@@ -2624,6 +2624,7 @@ fs_visitor::nir_emit_texture(const fs_builder &bld, nir_tex_instr *instr)
          switch (instr->op) {
          case nir_texop_txf:
          case nir_texop_txf_ms:
+         case nir_texop_samples_identical:
             coordinate = retype(src, BRW_REGISTER_TYPE_D);
             break;
          default:
@@ -2686,7 +2687,8 @@ fs_visitor::nir_emit_texture(const fs_builder &bld, nir_tex_instr *instr)
       }
    }
 
-   if (instr->op == nir_texop_txf_ms) {
+   if (instr->op == nir_texop_txf_ms ||
+       instr->op == nir_texop_samples_identical) {
       if (devinfo->gen >= 7 &&
           key_tex->compressed_multisample_layout_mask & (1 << sampler)) {
          mcs = emit_mcs_fetch(coordinate, instr->coord_components, sampler_reg);
diff --git a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
index a7bd9ce..66cbbd2 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
@@ -259,6 +259,22 @@ fs_visitor::emit_texture(ir_texture_opcode op,
       lod = fs_reg(0u);
    }
 
+   if (op == ir_samples_identical) {
+      fs_reg dst = vgrf(glsl_type::get_instance(dest_type->base_type, 1, 1));
+
+      /* If mcs is an immediate value, it means there is no MCS.  In that case
+       * just return false.
+       */
+      if (mcs.file == BRW_IMMEDIATE_VALUE) {
+         bld.MOV(dst, fs_reg(0));
+      } else {
+         bld.CMP(dst, mcs, src_reg(0u), BRW_CONDITIONAL_EQ);
+      }
+
+      this->result = dst;
+      return;
+   }
+
    if (coordinate.file != BAD_FILE) {
       /* FINISHME: Texture coordinate rescaling doesn't work with non-constant
        * samplers.  This should only be a problem with GL_CLAMP on Gen7.
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_nir.cpp b/src/mesa/drivers/dri/i965/brw_vec4_nir.cpp
index c93227c..98a4d3b 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_nir.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_nir.cpp
@@ -1615,6 +1615,7 @@ vec4_visitor::nir_emit_texture(nir_tex_instr *instr)
          switch (instr->op) {
          case nir_texop_txf:
          case nir_texop_txf_ms:
+         case nir_texop_samples_identical:
             coordinate = get_nir_src(instr->src[i].src, BRW_REGISTER_TYPE_D,
                                      src_size);
             coord_type = glsl_type::ivec(src_size);
@@ -1695,7 +1696,8 @@ vec4_visitor::nir_emit_texture(nir_tex_instr *instr)
       }
    }
 
-   if (instr->op == nir_texop_txf_ms) {
+   if (instr->op == nir_texop_txf_ms ||
+       instr->op == nir_texop_samples_identical) {
       assert(coord_type != NULL);
       if (devinfo->gen >= 7 &&
           key_tex->compressed_multisample_layout_mask & (1 << sampler)) {
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
index fda3d7c..d8a0f22 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
@@ -909,6 +909,17 @@ vec4_visitor::emit_texture(ir_texture_opcode op,
       unreachable("TXB is not valid for vertex shaders.");
    case ir_lod:
       unreachable("LOD is not valid for vertex shaders.");
+   case ir_samples_identical: {
+      /* If mcs is an immediate value, it means there is no MCS.  In that case
+       * just return false.
+       */
+      if (mcs.file == BRW_IMMEDIATE_VALUE) {
+         emit(MOV(dest, src_reg(0u)));
+      } else {
+         emit(CMP(dest, mcs, src_reg(0u), BRW_CONDITIONAL_EQ));
+      }
+      return;
+   }
    default:
       unreachable("Unrecognized tex op");
    }
diff --git a/src/mesa/drivers/dri/i965/intel_extensions.c b/src/mesa/drivers/dri/i965/intel_extensions.c
index 386b63c..2e2459c 100644
--- a/src/mesa/drivers/dri/i965/intel_extensions.c
+++ b/src/mesa/drivers/dri/i965/intel_extensions.c
@@ -333,6 +333,7 @@ intelInitExtensions(struct gl_context *ctx)
       ctx->Extensions.ARB_texture_compression_bptc = true;
       ctx->Extensions.ARB_texture_view = true;
       ctx->Extensions.ARB_shader_storage_buffer_object = true;
+      ctx->Extensions.EXT_shader_samples_identical = true;
 
       if (can_do_pipelined_register_writes(brw)) {
          ctx->Extensions.ARB_draw_indirect = true;
-- 
2.1.0