microsoft/compiler: Add a max shader model option

Reviewed-by: Enrico Galli <enrico.galli@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17603>

src/microsoft/compiler/nir_to_dxil.c

@@ -5703,6 +5703,11 @@ nir_to_dxil(struct nir_shader *s, const struct nir_to_dxil_options *opts,
    debug_dxil = (int)debug_get_option_debug_dxil();
    blob_init(blob);
 
+   if (opts->shader_model_max < SHADER_MODEL_6_1) {
+      debug_printf("D3D12: cannot support emitting shader model 6.0 or lower\n");
+      return false;
+   }
+
    struct ntd_context *ctx = calloc(1, sizeof(*ctx));
    if (!ctx)
       return false;
@@ -5775,6 +5780,13 @@ nir_to_dxil(struct nir_shader *s, const struct nir_to_dxil_options *opts,
       goto out;
    }
 
+   assert(ctx->mod.major_version == 6 && ctx->mod.minor_version >= 1);
+   if ((ctx->mod.major_version << 16 | ctx->mod.minor_version) > opts->shader_model_max) {
+      debug_printf("D3D12: max shader model exceeded\n");
+      retval = false;
+      goto out;
+   }
+
    if (debug_dxil & DXIL_DEBUG_DUMP_MODULE) {
       struct dxil_dumper *dumper = dxil_dump_create();
       dxil_dump_module(dumper, &ctx->mod);

src/microsoft/compiler/nir_to_dxil.h

@@ -80,6 +80,12 @@ enum dxil_environment {
    DXIL_ENVIRONMENT_VULKAN,
 };
 
+enum dxil_shader_model {
+   SHADER_MODEL_6_0 = 0x60000,
+   SHADER_MODEL_6_1,
+   SHADER_MODEL_6_2,
+};
+
 struct nir_to_dxil_options {
    bool interpolate_at_vertex;
    bool lower_int16;
@@ -90,6 +96,7 @@ struct nir_to_dxil_options {
    unsigned num_kernel_globals;
    unsigned input_clip_size;
    enum dxil_environment environment;
+   uint32_t shader_model_max;
 };
 
 bool