diff --git a/src/gallium/drivers/llvmpipe/lp_rast.h b/src/gallium/drivers/llvmpipe/lp_rast.h
index 10c2096525d..c1e712dc2df 100644
--- a/src/gallium/drivers/llvmpipe/lp_rast.h
+++ b/src/gallium/drivers/llvmpipe/lp_rast.h
@@ -382,7 +382,7 @@ lp_rast_arg_null( void )
 #define LP_RAST_FLAGS_BLIT           (0x8)
 
 struct lp_bin_info {
-   unsigned type:8;
+   unsigned type:8;    // bitmask of LP_RAST_FLAGS_x
    unsigned count:24;
 };
 
diff --git a/src/gallium/drivers/llvmpipe/lp_setup_rect.c b/src/gallium/drivers/llvmpipe/lp_setup_rect.c
index 74c56893991..6e5d5ba65ea 100644
--- a/src/gallium/drivers/llvmpipe/lp_setup_rect.c
+++ b/src/gallium/drivers/llvmpipe/lp_setup_rect.c
@@ -206,7 +206,7 @@ partial(struct lp_setup_context *setup,
         const struct lp_rast_rectangle *rect,
         boolean opaque,
         unsigned ix, unsigned iy,
-        unsigned mask)
+        unsigned mask) // RECT_PLANE_x bits
 {
    if (mask == 0) {
       assert(rect->box.x0 <= ix * TILE_SIZE);