r600: always export a position from vertex shader

This fixes piglit glsl-1.40-tf-no-position from gpu hanging on my rv635
at least.

Signed-off-by: Dave Airlie <airlied@redhat.com>

diff --git a/src/gallium/drivers/r600/r600_shader.c b/src/gallium/drivers/r600/r600_shader.c
index db45dfd22663ebfb0f7b55b1b378b0606e9ce4da..ab0b5e28782da986b7016d983c3f6a270b59f91b 100644 (file)
--- a/src/gallium/drivers/r600/r600_shader.c
+++ b/src/gallium/drivers/r600/r600_shader.c
@@ -1751,6 +1751,23 @@ static int r600_shader_from_tgsi(struct r600_screen *rscreen,
                }
        }
 
+        /* add fake position export */
+       if (ctx.type == TGSI_PROCESSOR_VERTEX && next_pos_base == 60) {
+                       memset(&output[j], 0, sizeof(struct r600_bytecode_output));
+                       output[j].gpr = 0;
+                       output[j].elem_size = 3;
+                       output[j].swizzle_x = 7;
+                       output[j].swizzle_y = 7;
+                       output[j].swizzle_z = 7;
+                       output[j].swizzle_w = 7;
+                       output[j].burst_count = 1;
+                       output[j].barrier = 1;
+                       output[j].type = V_SQ_CF_ALLOC_EXPORT_WORD0_SQ_EXPORT_POS;
+                       output[j].array_base = next_pos_base;
+                       output[j].inst = BC_INST(ctx.bc, V_SQ_CF_ALLOC_EXPORT_WORD1_SQ_CF_INST_EXPORT);
+                       j++;
+       }
+
        /* add fake param output for vertex shader if no param is exported */
        if (ctx.type == TGSI_PROCESSOR_VERTEX && next_param_base == 0) {
                        memset(&output[j], 0, sizeof(struct r600_bytecode_output));