radeonsi: add the vertex shader position output if it's missing

This fixes a lockup in piglit/spec/glsl-1.40/execution/tf-no-position.

Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>

diff --git a/src/gallium/drivers/radeonsi/radeonsi_shader.c b/src/gallium/drivers/radeonsi/radeonsi_shader.c
index 42db8ca..9f81a7b 100644 (file)
--- a/src/gallium/drivers/radeonsi/radeonsi_shader.c
+++ b/src/gallium/drivers/radeonsi/radeonsi_shader.c
@@ -1076,6 +1076,19 @@ handle_semantic:
        if (si_shader_ctx->type == TGSI_PROCESSOR_VERTEX) {
                unsigned pos_idx = 0;
 
+               /* We need to add the position output manually if it's missing. */
+               if (!pos_args[0][0]) {
+                       pos_args[0][0] = lp_build_const_int32(base->gallivm, 0xf); /* writemask */
+                       pos_args[0][1] = uint->zero; /* EXEC mask */
+                       pos_args[0][2] = uint->zero; /* last export? */
+                       pos_args[0][3] = lp_build_const_int32(base->gallivm, V_008DFC_SQ_EXP_POS);
+                       pos_args[0][4] = uint->zero; /* COMPR flag */
+                       pos_args[0][5] = base->zero; /* X */
+                       pos_args[0][6] = base->zero; /* Y */
+                       pos_args[0][7] = base->zero; /* Z */
+                       pos_args[0][8] = base->one;  /* W */
+               }
+
                for (i = 0; i < 4; i++)
                        if (pos_args[i][0])
                                shader->nr_pos_exports++;