i965: Virtualize vec4_visitor::emit_urb_slot().

This avoids a downcast of key, which won't exist in the base class soon.

I'm not a huge fan of this patch, but given that we're currently using
inheritance, this seems like the "right" way to do it.  The alternative
is to make key a void pointer in the parent class and continue
downcasting.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Chris Forbes <chrisf@ijw.co.nz>

4 files changed, 28 insertions, 16 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_vec4.h b/src/mesa/drivers/dri/i965/brw_vec4.h
index 10439f2..7df87b5 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4.h
+++ b/src/mesa/drivers/dri/i965/brw_vec4.h
@@ -360,7 +360,7 @@ public:
    void emit_ndc_computation();
    void emit_psiz_and_flags(dst_reg reg);
    vec4_instruction *emit_generic_urb_slot(dst_reg reg, int varying);
-   void emit_urb_slot(dst_reg reg, int varying);
+   virtual void emit_urb_slot(dst_reg reg, int varying);
 
    void emit_shader_time_begin();
    void emit_shader_time_end();
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
index f85f2f9..034286f 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
@@ -3233,21 +3233,6 @@ vec4_visitor::emit_urb_slot(dst_reg reg, int varying)
    case BRW_VARYING_SLOT_PAD:
       /* No need to write to this slot */
       break;
-   case VARYING_SLOT_COL0:
-   case VARYING_SLOT_COL1:
-   case VARYING_SLOT_BFC0:
-   case VARYING_SLOT_BFC1: {
-      /* These built-in varyings are only supported in compatibility mode,
-       * and we only support GS in core profile.  So, this must be a vertex
-       * shader.
-       */
-      assert(stage == MESA_SHADER_VERTEX);
-      vec4_instruction *inst = emit_generic_urb_slot(reg, varying);
-      if (((struct brw_vs_prog_key *) key)->clamp_vertex_color)
-         inst->saturate = true;
-      break;
-   }
-
    default:
       emit_generic_urb_slot(reg, varying);
       break;
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_vs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_vs_visitor.cpp
index f81ee4e..442cefd 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_vs_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_vs_visitor.cpp
@@ -202,6 +202,32 @@ vec4_vs_visitor::emit_urb_write_opcode(bool complete)
 
 
 void
+vec4_vs_visitor::emit_urb_slot(dst_reg reg, int varying)
+{
+   reg.type = BRW_REGISTER_TYPE_F;
+   output_reg[varying].type = reg.type;
+
+   switch (varying) {
+   case VARYING_SLOT_COL0:
+   case VARYING_SLOT_COL1:
+   case VARYING_SLOT_BFC0:
+   case VARYING_SLOT_BFC1: {
+      /* These built-in varyings are only supported in compatibility mode,
+       * and we only support GS in core profile.  So, this must be a vertex
+       * shader.
+       */
+      vec4_instruction *inst = emit_generic_urb_slot(reg, varying);
+      if (key->clamp_vertex_color)
+         inst->saturate = true;
+      break;
+   }
+   default:
+      return vec4_visitor::emit_urb_slot(reg, varying);
+   }
+}
+
+
+void
 vec4_vs_visitor::emit_clip_distances(dst_reg reg, int offset)
 {
    /* From the GLSL 1.30 spec, section 7.1 (Vertex Shader Special Variables):
diff --git a/src/mesa/drivers/dri/i965/brw_vs.h b/src/mesa/drivers/dri/i965/brw_vs.h
index e98679a..3a847fcd 100644
--- a/src/mesa/drivers/dri/i965/brw_vs.h
+++ b/src/mesa/drivers/dri/i965/brw_vs.h
@@ -103,6 +103,7 @@ protected:
    virtual void emit_program_code();
    virtual void emit_thread_end();
    virtual void emit_urb_write_header(int mrf);
+   virtual void emit_urb_slot(dst_reg reg, int varying);
    virtual vec4_instruction *emit_urb_write_opcode(bool complete);
 
 private: