draw: implement support for the VERTEXID_NOBASE and BASEVERTEX semantics.

This fixes 4 vertexid related piglit tests with llvmpipe due to switching
behavior of vertexid to the one gl expects.
(Won't fix non-llvm draw path since we don't get the basevertex currently.)

2 files changed, 12 insertions, 0 deletions

diff --git a/src/gallium/auxiliary/gallivm/lp_bld_tgsi.h b/src/gallium/auxiliary/gallivm/lp_bld_tgsi.h
index 029ca3c8410..b411f05674d 100644
--- a/src/gallium/auxiliary/gallivm/lp_bld_tgsi.h
+++ b/src/gallium/auxiliary/gallivm/lp_bld_tgsi.h
@@ -162,7 +162,9 @@ struct lp_tgsi_info
 struct lp_bld_tgsi_system_values {
    LLVMValueRef instance_id;
    LLVMValueRef vertex_id;
+   LLVMValueRef vertex_id_nobase;
    LLVMValueRef prim_id;
+   LLVMValueRef basevertex;
 };
 
 
diff --git a/src/gallium/auxiliary/gallivm/lp_bld_tgsi_soa.c b/src/gallium/auxiliary/gallivm/lp_bld_tgsi_soa.c
index 76b9d69264f..3dfff05c22b 100644
--- a/src/gallium/auxiliary/gallivm/lp_bld_tgsi_soa.c
+++ b/src/gallium/auxiliary/gallivm/lp_bld_tgsi_soa.c
@@ -1538,6 +1538,16 @@ emit_fetch_system_value(
       atype = TGSI_TYPE_UNSIGNED;
       break;
 
+   case TGSI_SEMANTIC_VERTEXID_NOBASE:
+      res = bld->system_values.vertex_id_nobase;
+      atype = TGSI_TYPE_UNSIGNED;
+      break;
+
+   case TGSI_SEMANTIC_BASEVERTEX:
+      res = bld->system_values.basevertex;
+      atype = TGSI_TYPE_UNSIGNED;
+      break;
+
    case TGSI_SEMANTIC_PRIMID:
       res = bld->system_values.prim_id;
       atype = TGSI_TYPE_UNSIGNED;