i965: Add support for gl_VertexID and gl_InstanceID.

The compiler setup for these VF-uploaded attributes looks a little
cheesy with mixing system values and real VBO-sourced attributes.  It
would be nice if we could just compute the ATTR[] map to GRF index up
front and use it at visit time instead of using ir->location in the
ATTR file.  However, we don't know the reg_offset at
visit(ir_variable *) time, so we can't do the mapping that early.

Fixes piglit vertexid test.

Reviewed-by: Ian Romanick <[email protected]>

1 files changed, 10 insertions, 1 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp b/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
index dc39f17614a..54bbe1347b9 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
@@ -35,7 +35,7 @@ int
 vec4_visitor::setup_attributes(int payload_reg)
 {
    int nr_attributes;
-   int attribute_map[VERT_ATTRIB_MAX];
+   int attribute_map[VERT_ATTRIB_MAX + 1];
 
    nr_attributes = 0;
    for (int i = 0; i < VERT_ATTRIB_MAX; i++) {
@@ -45,6 +45,15 @@ vec4_visitor::setup_attributes(int payload_reg)
       }
    }
 
+   /* VertexID is stored by the VF as the last vertex element, but we
+    * don't represent it with a flag in inputs_read, so we call it
+    * VERT_ATTRIB_MAX.
+    */
+   if (prog_data->uses_vertexid) {
+      attribute_map[VERT_ATTRIB_MAX] = payload_reg + nr_attributes;
+      nr_attributes++;
+   }
+
    foreach_list(node, &this->instructions) {
       vec4_instruction *inst = (vec4_instruction *)node;