[Mesa-dev] [PATCH v3 02/10] i965: initialize SPIR-V capabilities

[Eduardo Lima Mitev]

From: Alejandro Piñeiro <apinheiro at igalia.com>

Needed for ARB_gl_spirv. Right now those are the same that the intel
vulkan driver, but those are not shared. From the ARB_spirv_extensions
spec:

   "3. If a new GL extension is added that includes SPIR-V support via
   a new SPIR-V extension does it's SPIR-V extension also get
   enumerated by the SPIR_V_EXTENSIONS_ARB query?.

   RESOLVED. Yes. It's good to include it for consistency. Any SPIR-V
   functionality supported beyond the SPIR-V version that is required
   for the GL API version should be enumerated."

Reading between lines, there is the possibility of specific GL
extensions enabling specific SPIR-V extensions (so capabilities). That
would mean that it is possible that OpenGL and Vulkan not having the
same capabilities supported, even for the same driver. So for now we
keep them separate. Perhaps in the future it is better to keep them
the same and synced.

Note: we initialize SPIR-V capabilities at brwCreateContext instead of
the usual brw_initialize_context_constants because we want to do that
only for version >= 3.3. At brw_initialize_context_constans GL version
is still not computed.

v2:
   * Rebase update (SpirVCapabilities not a pointer anymore)
   * Fill spirv capabilities for OpenGL >= 3.3 (Ian Romanick)
---
 src/mesa/drivers/dri/i965/brw_context.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/src/mesa/drivers/dri/i965/brw_context.c b/src/mesa/drivers/dri/i965/brw_context.c
index 126c187f629..a37bbb753d8 100644
--- a/src/mesa/drivers/dri/i965/brw_context.c
+++ b/src/mesa/drivers/dri/i965/brw_context.c
@@ -75,6 +75,7 @@
 #include "util/debug.h"
 #include "isl/isl.h"
 
+#include "compiler/spirv/nir_spirv.h"
 /***************************************
  * Mesa's Driver Functions
  ***************************************/
@@ -338,6 +339,21 @@ brw_init_driver_functions(struct brw_context *brw,
       brw_deserialize_program_binary;
 }
 
+static void
+brw_initialize_spirv_supported_capabilities(struct brw_context *brw)
+{
+   const struct gen_device_info *devinfo = &brw->screen->devinfo;
+   struct gl_context *ctx = &brw->ctx;
+
+   ctx->Const.SpirVCapabilities.float64 = devinfo->gen >= 8;
+   ctx->Const.SpirVCapabilities.int64 = devinfo->gen >= 8;
+   ctx->Const.SpirVCapabilities.tessellation = true;
+   ctx->Const.SpirVCapabilities.draw_parameters = true;
+   ctx->Const.SpirVCapabilities.image_write_without_format = true;
+   ctx->Const.SpirVCapabilities.multiview = true;
+   ctx->Const.SpirVCapabilities.variable_pointers = true;
+}
+
 static void
 brw_initialize_context_constants(struct brw_context *brw)
 {
@@ -1067,6 +1083,10 @@ brwCreateContext(gl_api api,
    _mesa_override_extensions(ctx);
    _mesa_compute_version(ctx);
 
+   /* GL_ARB_gl_spirv */
+   if (ctx->Version >= 33)
+      brw_initialize_spirv_supported_capabilities(brw);
+
    _mesa_initialize_dispatch_tables(ctx);
    _mesa_initialize_vbo_vtxfmt(ctx);
 
-- 
2.15.1