shader: fixes viewport-no-gs.shader_test

Add fragment gl_ViewportIndex support.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

src/vrend_shader.c

@@ -138,6 +138,7 @@ struct dump_ctx {
    bool has_clipvertex;
    bool has_clipvertex_so;
    bool has_viewport_idx;
+   bool has_frag_viewport_idx;
 };
 
 static inline const char *tgsi_proc_to_prefix(int shader_type)
@@ -316,6 +317,17 @@ iter_declaration(struct tgsi_iterate_context *iter,
             ctx->glsl_ver_required = 150;
             break;
          }
+      case TGSI_SEMANTIC_VIEWPORT_INDEX:
+         if (iter->processor.Processor == TGSI_PROCESSOR_FRAGMENT) {
+            ctx->inputs[i].glsl_predefined_no_emit = true;
+            ctx->inputs[i].glsl_no_index = true;
+            ctx->inputs[i].is_int = true;
+            ctx->inputs[i].override_no_wm = true;
+            name_prefix = "gl_ViewportIndex";
+            if (ctx->glsl_ver_required >= 140)
+               ctx->has_frag_viewport_idx = true;
+            break;
+         }
       case TGSI_SEMANTIC_LAYER:
          if (iter->processor.Processor == TGSI_PROCESSOR_FRAGMENT) {
             name_prefix = "gl_Layer";
@@ -2030,6 +2042,8 @@ static char *emit_header(struct dump_ctx *ctx, char *glsl_hdr)
       STRCAT_WITH_RET(glsl_hdr, "#extension GL_ARB_texture_gather : require\n");
    if (ctx->has_viewport_idx)
       STRCAT_WITH_RET(glsl_hdr, "#extension GL_ARB_viewport_array : require\n");
+   if (ctx->has_frag_viewport_idx)
+      STRCAT_WITH_RET(glsl_hdr, "#extension GL_ARB_fragment_layer_viewport : require\n");
    if (ctx->uses_stencil_export)
       STRCAT_WITH_RET(glsl_hdr, "#extension GL_ARB_shader_stencil_export : require\n");
    if (ctx->uses_layer)