intel: Don't keep intel->pClipRects, and instead just calculate it when needed.

This avoids issues with dereferencing stale cliprects around intel_draw_buffer
time.  Additionally, take advantage of cliprects staying constant for FBOs and
DRI2, and emit cliprects in the batchbuffer instead of having to flush batch
each time they change.

4 files changed, 39 insertions, 13 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_draw.c b/src/mesa/drivers/dri/i965/brw_draw.c
index 6c71b4abcf..05d6f42ab4 100644
--- a/src/mesa/drivers/dri/i965/brw_draw.c
+++ b/src/mesa/drivers/dri/i965/brw_draw.c
@@ -282,24 +282,21 @@ static GLboolean brw_try_draw_prims( GLcontext *ctx,
 
    LOCK_HARDWARE(intel);
 
-   if (brw->intel.numClipRects == 0) {
+   if (!intel->constant_cliprect && intel->driDrawable->numClipRects == 0) {
       UNLOCK_HARDWARE(intel);
       return GL_TRUE;
    }
 
+   /* Flush the batch if it's approaching full, so that we don't wrap while
+    * we've got validated state that needs to be in the same batch as the
+    * primitives.  This fraction is just a guess (minimal full state plus
+    * a primitive is around 512 bytes), and would be better if we had
+    * an upper bound of how much we might emit in a single
+    * brw_try_draw_prims().
+    */
+   intel_batchbuffer_require_space(intel->batch, intel->batch->size / 4,
+				   LOOP_CLIPRECTS);
    {
-      /* Flush the batch if it's approaching full, so that we don't wrap while
-       * we've got validated state that needs to be in the same batch as the
-       * primitives.  This fraction is just a guess (minimal full state plus
-       * a primitive is around 512 bytes), and would be better if we had
-       * an upper bound of how much we might emit in a single
-       * brw_try_draw_prims().
-       */
-      if (intel->batch->ptr - intel->batch->map > intel->batch->size * 3 / 4
-	/* brw_emit_prim may change the cliprect_mode to LOOP_CLIPRECTS */
-	  || intel->batch->cliprect_mode != LOOP_CLIPRECTS)
-	      intel_batchbuffer_flush(intel->batch);
-
       /* Set the first primitive early, ahead of validate_state:
        */
       brw_set_prim(brw, prim[0].mode);
diff --git a/src/mesa/drivers/dri/i965/brw_misc_state.c b/src/mesa/drivers/dri/i965/brw_misc_state.c
index afa8694ebb..e347dd2244 100644
--- a/src/mesa/drivers/dri/i965/brw_misc_state.c
+++ b/src/mesa/drivers/dri/i965/brw_misc_state.c
@@ -71,6 +71,33 @@ const struct brw_tracked_state brw_blend_constant_color = {
    .emit = upload_blend_constant_color
 };
 
+/* Constant single cliprect for framebuffer object or DRI2 drawing */
+static void upload_drawing_rect(struct brw_context *brw)
+{
+   struct intel_context *intel = &brw->intel;
+   GLcontext *ctx = &intel->ctx;
+
+   if (!intel->constant_cliprect)
+      return;
+
+   BEGIN_BATCH(4, NO_LOOP_CLIPRECTS);
+   OUT_BATCH(_3DSTATE_DRAWRECT_INFO_I965);
+   OUT_BATCH(0); /* xmin, ymin */
+   OUT_BATCH(((ctx->DrawBuffer->Width - 1) & 0xffff) |
+	    ((ctx->DrawBuffer->Height - 1) << 16));
+   OUT_BATCH(0);
+   ADVANCE_BATCH();
+}
+
+const struct brw_tracked_state brw_drawing_rect = {
+   .dirty = {
+      .mesa = _NEW_BUFFERS,
+      .brw = 0,
+      .cache = 0
+   },
+   .emit = upload_drawing_rect
+};
+
 /**
  * Upload the binding table pointers, which point each stage's array of surface
  * state pointers.
diff --git a/src/mesa/drivers/dri/i965/brw_state.h b/src/mesa/drivers/dri/i965/brw_state.h
index 4c04036ef0..a27ef1f8bc 100644
--- a/src/mesa/drivers/dri/i965/brw_state.h
+++ b/src/mesa/drivers/dri/i965/brw_state.h
@@ -79,6 +79,7 @@ const struct brw_tracked_state brw_pipe_control;
 const struct brw_tracked_state brw_clear_surface_cache;
 const struct brw_tracked_state brw_clear_batch_cache;
 
+const struct brw_tracked_state brw_drawing_rect;
 const struct brw_tracked_state brw_indices;
 const struct brw_tracked_state brw_vertices;
 
diff --git a/src/mesa/drivers/dri/i965/brw_state_upload.c b/src/mesa/drivers/dri/i965/brw_state_upload.c
index eef06e81a7..8d57daf3ab 100644
--- a/src/mesa/drivers/dri/i965/brw_state_upload.c
+++ b/src/mesa/drivers/dri/i965/brw_state_upload.c
@@ -99,6 +99,7 @@ const struct brw_tracked_state *atoms[] =
    &brw_psp_urb_cbs,
 #endif
 
+   &brw_drawing_rect,
    &brw_indices,
    &brw_vertices,