Mesa (master): mesa: Simplify _mesa_primitive_restart_index().

[Kenneth Graunke]

Module: Mesa
Branch: master
Commit: 8c5a938171d0566b087fdfb5c422464aa005e8ed
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=8c5a938171d0566b087fdfb5c422464aa005e8ed

Author: Kenneth Graunke <kenneth at whitecape.org>
Date:   Thu May  4 01:08:25 2017 -0700

mesa: Simplify _mesa_primitive_restart_index().

We can use a simple shift equation rather than a switch statement.

Reviewed-by: Rafael Antognolli <rafael.antognolli at intel.com>
Reviewed-by: Marek Olšák <marek.olsak at amd.com>

---

 src/mesa/main/varray.c | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/src/mesa/main/varray.c b/src/mesa/main/varray.c
index eda86ec6a8..9497090e88 100644
--- a/src/mesa/main/varray.c
+++ b/src/mesa/main/varray.c
@@ -1959,16 +1959,8 @@ _mesa_primitive_restart_index(const struct gl_context *ctx,
     *  is used."
     */
    if (ctx->Array.PrimitiveRestartFixedIndex) {
-      switch (index_size) {
-      case 1:
-         return 0xff;
-      case 2:
-         return 0xffff;
-      case 4:
-         return 0xffffffff;
-      default:
-         assert(!"_mesa_primitive_restart_index: Invalid index size.");
-      }
+      /* 1 -> 0xff, 2 -> 0xffff, 4 -> 0xffffffff */
+      return 0xffffffffu >> 8 * (4 - index_size);
    }
 
    return ctx->Array.RestartIndex;