[Mesa-dev] [PATCH 1/2] glsl: add subpass image type

[Dave Airlie]

From: Dave Airlie <airlied at redhat.com>

SPIR-V/Vulkan have a special image type for input attachments
called the subpass type. It has different characteristics than
other images types.

The main one being it can only be an input image to fragment
shaders and loads from it are relative to the frag coord.

This adds support for it to the GLSL types. Unfortunately
we've run out of space in the sampler dim in types, so we
need to use another bit.
---
 src/compiler/builtin_type_macros.h |  2 ++
 src/compiler/glsl_types.cpp        | 12 ++++++++++++
 src/compiler/glsl_types.h          |  5 +++--
 src/compiler/nir/nir.h             |  1 +
 4 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/src/compiler/builtin_type_macros.h b/src/compiler/builtin_type_macros.h
index da3f19e..8af0e2a 100644
--- a/src/compiler/builtin_type_macros.h
+++ b/src/compiler/builtin_type_macros.h
@@ -159,6 +159,8 @@ DECL_TYPE(uimageCubeArray, GL_UNSIGNED_INT_IMAGE_CUBE_MAP_ARRAY,       GLSL_TYPE
 DECL_TYPE(uimage2DMS,      GL_UNSIGNED_INT_IMAGE_2D_MULTISAMPLE,       GLSL_TYPE_IMAGE, GLSL_SAMPLER_DIM_MS,     0, 0, GLSL_TYPE_UINT)
 DECL_TYPE(uimage2DMSArray, GL_UNSIGNED_INT_IMAGE_2D_MULTISAMPLE_ARRAY, GLSL_TYPE_IMAGE, GLSL_SAMPLER_DIM_MS,     0, 1, GLSL_TYPE_UINT)
 
+DECL_TYPE(imageSubpass,    0,                                          GLSL_TYPE_IMAGE, GLSL_SAMPLER_DIM_SUBPASS,0, 0, GLSL_TYPE_FLOAT)
+
 DECL_TYPE(atomic_uint, GL_UNSIGNED_INT_ATOMIC_COUNTER, GLSL_TYPE_ATOMIC_UINT, 1, 1)
 
 STRUCT_TYPE(gl_DepthRangeParameters)
diff --git a/src/compiler/glsl_types.cpp b/src/compiler/glsl_types.cpp
index 641644d..bf72419 100644
--- a/src/compiler/glsl_types.cpp
+++ b/src/compiler/glsl_types.cpp
@@ -674,6 +674,8 @@ glsl_type::get_sampler_instance(enum glsl_sampler_dim dim,
             return error_type;
          else
             return samplerExternalOES_type;
+      case GLSL_SAMPLER_DIM_SUBPASS:
+         return error_type;
       }
    case GLSL_TYPE_INT:
       if (shadow)
@@ -701,6 +703,8 @@ glsl_type::get_sampler_instance(enum glsl_sampler_dim dim,
          return (array ? isampler2DMSArray_type : isampler2DMS_type);
       case GLSL_SAMPLER_DIM_EXTERNAL:
          return error_type;
+      case GLSL_SAMPLER_DIM_SUBPASS:
+         return error_type;
       }
    case GLSL_TYPE_UINT:
       if (shadow)
@@ -728,6 +732,8 @@ glsl_type::get_sampler_instance(enum glsl_sampler_dim dim,
          return (array ? usampler2DMSArray_type : usampler2DMS_type);
       case GLSL_SAMPLER_DIM_EXTERNAL:
          return error_type;
+      case GLSL_SAMPLER_DIM_SUBPASS:
+         return error_type;
       }
    default:
       return error_type;
@@ -740,6 +746,8 @@ const glsl_type *
 glsl_type::get_image_instance(enum glsl_sampler_dim dim,
                               bool array, glsl_base_type type)
 {
+   if (dim == GLSL_SAMPLER_DIM_SUBPASS)
+      return imageSubpass_type;
    switch (type) {
    case GLSL_TYPE_FLOAT:
       switch (dim) {
@@ -764,6 +772,7 @@ glsl_type::get_image_instance(enum glsl_sampler_dim dim,
       case GLSL_SAMPLER_DIM_MS:
          return (array ? image2DMSArray_type : image2DMS_type);
       case GLSL_SAMPLER_DIM_EXTERNAL:
+      case GLSL_SAMPLER_DIM_SUBPASS:
          return error_type;
       }
    case GLSL_TYPE_INT:
@@ -789,6 +798,7 @@ glsl_type::get_image_instance(enum glsl_sampler_dim dim,
       case GLSL_SAMPLER_DIM_MS:
          return (array ? iimage2DMSArray_type : iimage2DMS_type);
       case GLSL_SAMPLER_DIM_EXTERNAL:
+      case GLSL_SAMPLER_DIM_SUBPASS:
          return error_type;
       }
    case GLSL_TYPE_UINT:
@@ -814,6 +824,7 @@ glsl_type::get_image_instance(enum glsl_sampler_dim dim,
       case GLSL_SAMPLER_DIM_MS:
          return (array ? uimage2DMSArray_type : uimage2DMS_type);
       case GLSL_SAMPLER_DIM_EXTERNAL:
+      case GLSL_SAMPLER_DIM_SUBPASS:
          return error_type;
       }
    default:
@@ -1975,6 +1986,7 @@ glsl_type::coordinate_components() const
    case GLSL_SAMPLER_DIM_RECT:
    case GLSL_SAMPLER_DIM_MS:
    case GLSL_SAMPLER_DIM_EXTERNAL:
+   case GLSL_SAMPLER_DIM_SUBPASS:
       size = 2;
       break;
    case GLSL_SAMPLER_DIM_3D:
diff --git a/src/compiler/glsl_types.h b/src/compiler/glsl_types.h
index 7c4827d..b1e2f7a 100644
--- a/src/compiler/glsl_types.h
+++ b/src/compiler/glsl_types.h
@@ -80,7 +80,8 @@ enum glsl_sampler_dim {
    GLSL_SAMPLER_DIM_RECT,
    GLSL_SAMPLER_DIM_BUF,
    GLSL_SAMPLER_DIM_EXTERNAL,
-   GLSL_SAMPLER_DIM_MS
+   GLSL_SAMPLER_DIM_MS,
+   GLSL_SAMPLER_DIM_SUBPASS, /* for vulkan input attachments */
 };
 
 enum glsl_interface_packing {
@@ -127,7 +128,7 @@ struct glsl_type {
    GLenum gl_type;
    glsl_base_type base_type;
 
-   unsigned sampler_dimensionality:3; /**< \see glsl_sampler_dim */
+   unsigned sampler_dimensionality:4; /**< \see glsl_sampler_dim */
    unsigned sampler_shadow:1;
    unsigned sampler_array:1;
    unsigned sampled_type:2;    /**< Type of data returned using this
diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h
index ff7c422..95659d5 100644
--- a/src/compiler/nir/nir.h
+++ b/src/compiler/nir/nir.h
@@ -1198,6 +1198,7 @@ nir_tex_instr_dest_size(nir_tex_instr *instr)
          case GLSL_SAMPLER_DIM_MS:
          case GLSL_SAMPLER_DIM_RECT:
          case GLSL_SAMPLER_DIM_EXTERNAL:
+         case GLSL_SAMPLER_DIM_SUBPASS:
             ret = 2;
             break;
          case GLSL_SAMPLER_DIM_3D:
-- 
2.5.5