intel/fs: Add support for compiling bindless shaders with resume shaders

Instead of depending on the driver to compile each resume shader
separately, we compile them all in one go in the back-end and build an
SBT as part of the shader program.  Shader relocs are used to make the
entries in the SBT point point to the correct resume shader.

Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8637>

src/intel/compiler/brw_fs_generator.cpp

@@ -2805,6 +2805,24 @@ fs_generator::add_const_data(void *data, unsigned size)
    }
 }
 
+void
+fs_generator::add_resume_sbt(unsigned num_resume_shaders, uint64_t *sbt)
+{
+   assert(brw_shader_stage_is_bindless(stage));
+   struct brw_bs_prog_data *bs_prog_data = brw_bs_prog_data(prog_data);
+   if (num_resume_shaders > 0) {
+      bs_prog_data->resume_sbt_offset =
+         brw_append_data(p, sbt, num_resume_shaders * sizeof(uint64_t), 32);
+      for (unsigned i = 0; i < num_resume_shaders; i++) {
+         size_t offset = bs_prog_data->resume_sbt_offset + i * sizeof(*sbt);
+         assert(offset <= UINT32_MAX);
+         brw_add_reloc(p, BRW_SHADER_RELOC_SHADER_START_OFFSET,
+                       BRW_SHADER_RELOC_TYPE_U32,
+                       (uint32_t)offset, (uint32_t)sbt[i]);
+      }
+   }
+}
+
 const unsigned *
 fs_generator::get_assembly()
 {