[Nouveau] [PATCH 10/19] nv50: VP_RESULT_MAP_SIZE has to be positive

[Ilia Mirkin]

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 at alum.mit.edu>
---
 src/gallium/drivers/nouveau/nv50/nv50_shader_state.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/gallium/drivers/nouveau/nv50/nv50_shader_state.c b/src/gallium/drivers/nouveau/nv50/nv50_shader_state.c
index ba4f592..265ef20 100644
--- a/src/gallium/drivers/nouveau/nv50/nv50_shader_state.c
+++ b/src/gallium/drivers/nouveau/nv50/nv50_shader_state.c
@@ -457,6 +457,7 @@ 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);
@@ -516,6 +517,8 @@ nv50_vp_gp_mapping(uint8_t *map, int m,
          oid += mv & 1;
       }
    }
+   if (!m)
+      map[m++] = 0;
    return m;
 }
 
@@ -540,6 +543,7 @@ 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);
-- 
1.8.3.2