nv50: VP_RESULT_MAP_SIZE has to be positive

Make sure that we never try to use a 0-sized map. This can happen when
using a gp, so add a dummy mapping when computing vp_gp_mapping in that
case.

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>

diff --git a/src/gallium/drivers/nouveau/nv50/nv50_shader_state.c b/src/gallium/drivers/nouveau/nv50/nv50_shader_state.c
index 6bd1974b4ae7edc314f2b7ad9076f541dafbee3c..9a435028704a32985cb9bb9b917b62fd7769101c 100644 (file)
--- a/src/gallium/drivers/nouveau/nv50/nv50_shader_state.c
+++ b/src/gallium/drivers/nouveau/nv50/nv50_shader_state.c
@@ -461,6 +461,7 @@ nv50_fp_linkage_validate(struct nv50_context *nv50)
       BEGIN_NV04(push, NV50_3D(SEMANTIC_PRIM_ID), 1);
       PUSH_DATA (push, primid);
 
+      assert(m > 0);
       BEGIN_NV04(push, NV50_3D(VP_RESULT_MAP_SIZE), 1);
       PUSH_DATA (push, m);
       BEGIN_NV04(push, NV50_3D(VP_RESULT_MAP(0)), n);
@@ -523,6 +524,8 @@ nv50_vp_gp_mapping(uint8_t *map, int m,
          oid += mv & 1;
       }
    }
+   if (!m)
+      map[m++] = 0;
    return m;
 }
 
@@ -547,6 +550,7 @@ nv50_gp_linkage_validate(struct nv50_context *nv50)
    BEGIN_NV04(push, NV50_3D(VP_GP_BUILTIN_ATTR_EN), 1);
    PUSH_DATA (push, vp->vp.attrs[2] | gp->vp.attrs[2]);
 
+   assert(m > 0);
    BEGIN_NV04(push, NV50_3D(VP_RESULT_MAP_SIZE), 1);
    PUSH_DATA (push, m);
    BEGIN_NV04(push, NV50_3D(VP_RESULT_MAP(0)), n);