vrend: Cache VS and FS id's in program to speed up comparison

This gives a 6% speed improvement with Unigine Heaven

v2: remove the unlikely for dual_src, the whole statement will
    be changed later (Chia-I Wu)

Signed-off-by: Gert Wollny <gert.wollny@collabora.com>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>

src/vrend_renderer.c

@@ -355,6 +355,7 @@ struct vrend_linked_shader_program {
 
    bool dual_src_linked;
    struct vrend_shader *ss[PIPE_SHADER_TYPES];
+   uint64_t vs_fs_key;
 
    uint32_t ubo_used_mask[PIPE_SHADER_TYPES];
    uint32_t samplers_used_mask[PIPE_SHADER_TYPES];
@@ -1589,6 +1590,7 @@ static struct vrend_linked_shader_program *add_shader_program(struct vrend_conte
 
    sprog->ss[PIPE_SHADER_VERTEX] = vs;
    sprog->ss[PIPE_SHADER_FRAGMENT] = fs;
+   sprog->vs_fs_key = (uint64_t)vs->id << 32 | fs->id;
    sprog->ss[PIPE_SHADER_GEOMETRY] = gs;
    sprog->ss[PIPE_SHADER_TESS_CTRL] = tcs;
    sprog->ss[PIPE_SHADER_TESS_EVAL] = tes;
@@ -1674,15 +1676,15 @@ static struct vrend_linked_shader_program *lookup_shader_program(struct vrend_co
                                                                  GLuint tes_id,
                                                                  bool dual_src)
 {
+   uint64_t vs_fs_key = (((uint64_t)vs_id) << 32) | fs_id;
+
    struct vrend_linked_shader_program *ent;
    LIST_FOR_EACH_ENTRY(ent, &ctx->sub->programs, head) {
       if (ent->dual_src_linked != dual_src)
          continue;
       if (ent->ss[PIPE_SHADER_COMPUTE])
          continue;
-      if (ent->ss[PIPE_SHADER_VERTEX]->id != vs_id)
+      if (unlikely(ent->vs_fs_key != vs_fs_key))
-        continue;
-      if (ent->ss[PIPE_SHADER_FRAGMENT]->id != fs_id)
          continue;
       if (ent->ss[PIPE_SHADER_GEOMETRY] &&
           ent->ss[PIPE_SHADER_GEOMETRY]->id != gs_id)