r600g: fix up vs export handling

[mesa.git] / src / gallium / drivers / r600 / r600_state.c

diff --git a/src/gallium/drivers/r600/r600_state.c b/src/gallium/drivers/r600/r600_state.c
index 294c400caa17f754a7da74aea15ef560e919bdc0..1350a1cf565855910c011ab3f6718d24984c39ba 100644 (file)
--- a/src/gallium/drivers/r600/r600_state.c
+++ b/src/gallium/drivers/r600/r600_state.c
@@ -2062,7 +2062,7 @@ void r600_pipe_shader_vs(struct pipe_context *ctx, struct r600_pipe_shader *shad
        struct r600_pipe_state *rstate = &shader->rstate;
        struct r600_shader *rshader = &shader->shader;
        unsigned spi_vs_out_id[10];
-       unsigned i, tmp;
+       unsigned i, tmp, nparams;
 
        /* clear previous register */
        rstate->nregs = 0;
@@ -2084,9 +2084,17 @@ void r600_pipe_shader_vs(struct pipe_context *ctx, struct r600_pipe_shader *shad
                                        spi_vs_out_id[i], 0xFFFFFFFF, NULL);
        }
 
+       /* Certain attributes (position, psize, etc.) don't count as params.
+        * VS is required to export at least one param and r600_shader_from_tgsi()
+        * takes care of adding a dummy export.
+        */
+       nparams = rshader->noutput - rshader->npos;
+       if (nparams < 1)
+               nparams = 1;
+
        r600_pipe_state_add_reg(rstate,
                        R_0286C4_SPI_VS_OUT_CONFIG,
-                       S_0286C4_VS_EXPORT_COUNT(rshader->noutput - 1),
+                       S_0286C4_VS_EXPORT_COUNT(nparams - 1),
                        0xFFFFFFFF, NULL);
        r600_pipe_state_add_reg(rstate,
                        R_028868_SQ_PGM_RESOURCES_VS,