mesa: Reset image unit state to the default values when a bound image is deleted.

The ES31-CTS.shader_image_load_store.basic-api-bind conformance test
expects the whole image unit state to be reset when the bound texture
object is deleted.  The ARB_shader_image_load_store extension is
rather vague regarding what should happen with image unit state other
than the texture object in that case, but the GL 4.2 and GLES 3.1
specifications (section "Automatic Unbinding of Deleted Objects")
explicitly require it to be reset to the default values.

Reviewed-by: Tapani Pälli <[email protected]>
Reviewed-by: Ian Romanick <[email protected]>

3 files changed, 23 insertions, 7 deletions

diff --git a/src/mesa/main/shaderimage.c b/src/mesa/main/shaderimage.c
index 2d8693150b1..48e3e09dd5d 100644
--- a/src/mesa/main/shaderimage.c
+++ b/src/mesa/main/shaderimage.c
@@ -394,17 +394,24 @@ is_image_format_supported(const struct gl_context *ctx, GLenum format)
    }
 }
 
+struct gl_image_unit
+_mesa_default_image_unit(struct gl_context *ctx)
+{
+   const struct gl_image_unit u = {
+      .Access = GL_READ_ONLY,
+      .Format = GL_R8,
+      ._ActualFormat = _mesa_get_shader_image_format(GL_R8)
+   };
+   return u;
+}
+
 void
 _mesa_init_image_units(struct gl_context *ctx)
 {
    unsigned i;
 
-   for (i = 0; i < ARRAY_SIZE(ctx->ImageUnits); ++i) {
-      struct gl_image_unit *u = &ctx->ImageUnits[i];
-      u->Access = GL_READ_ONLY;
-      u->Format = GL_R8;
-      u->_ActualFormat = _mesa_get_shader_image_format(u->Format);
-   }
+   for (i = 0; i < ARRAY_SIZE(ctx->ImageUnits); ++i)
+      ctx->ImageUnits[i] = _mesa_default_image_unit(ctx);
 }
 
 static GLboolean
diff --git a/src/mesa/main/shaderimage.h b/src/mesa/main/shaderimage.h
index d08ece81f11..bbe088a2459 100644
--- a/src/mesa/main/shaderimage.h
+++ b/src/mesa/main/shaderimage.h
@@ -43,6 +43,12 @@ mesa_format
 _mesa_get_shader_image_format(GLenum format);
 
 /**
+ * Get a single image unit struct with the default state.
+ */
+struct gl_image_unit
+_mesa_default_image_unit(struct gl_context *ctx);
+
+/**
  * Initialize a context's shader image units to the default state.
  */
 void
diff --git a/src/mesa/main/texobj.c b/src/mesa/main/texobj.c
index cd7cfd6a4fb..395e4d3359f 100644
--- a/src/mesa/main/texobj.c
+++ b/src/mesa/main/texobj.c
@@ -37,6 +37,7 @@
 #include "hash.h"
 #include "imports.h"
 #include "macros.h"
+#include "shaderimage.h"
 #include "teximage.h"
 #include "texobj.h"
 #include "texstate.h"
@@ -1411,8 +1412,10 @@ unbind_texobj_from_image_units(struct gl_context *ctx,
    for (i = 0; i < ctx->Const.MaxImageUnits; i++) {
       struct gl_image_unit *unit = &ctx->ImageUnits[i];
 
-      if (texObj == unit->TexObj)
+      if (texObj == unit->TexObj) {
          _mesa_reference_texobj(&unit->TexObj, NULL);
+         *unit = _mesa_default_image_unit(ctx);
+      }
    }
 }