diff --git a/dlls/wined3d/shader.c b/dlls/wined3d/shader.c
index e337f0b8fd2..0e884861c3a 100644
--- a/dlls/wined3d/shader.c
+++ b/dlls/wined3d/shader.c
@@ -2021,6 +2021,10 @@ static void shader_dump_register(struct wined3d_string_buffer *buffer,
             shader_addline(buffer, "vForkInstanceId");
             break;
 
+        case WINED3DSPR_JOININSTID:
+            shader_addline(buffer, "vJoinInstanceId");
+            break;
+
         case WINED3DSPR_INCONTROLPOINT:
             shader_addline(buffer, "vicp");
             break;
diff --git a/dlls/wined3d/shader_sm4.c b/dlls/wined3d/shader_sm4.c
index f30566567a3..050f656a6f7 100644
--- a/dlls/wined3d/shader_sm4.c
+++ b/dlls/wined3d/shader_sm4.c
@@ -311,6 +311,7 @@ enum wined3d_sm4_register_type
     WINED3D_SM5_RT_FUNCTION_POINTER        = 0x13,
     WINED3D_SM5_RT_OUTPUT_CONTROL_POINT_ID = 0x16,
     WINED3D_SM5_RT_FORK_INSTANCE_ID        = 0x17,
+    WINED3D_SM5_RT_JOIN_INSTANCE_ID        = 0x18,
     WINED3D_SM5_RT_INPUT_CONTROL_POINT     = 0x19,
     WINED3D_SM5_RT_OUTPUT_CONTROL_POINT    = 0x1a,
     WINED3D_SM5_RT_PATCH_CONSTANT_DATA     = 0x1b,
@@ -1056,7 +1057,7 @@ static const enum wined3d_shader_register_type register_type_table[] =
     /* UNKNOWN */                                ~0u,
     /* WINED3D_SM5_RT_OUTPUT_CONTROL_POINT_ID */ WINED3DSPR_OUTPOINTID,
     /* WINED3D_SM5_RT_FORK_INSTANCE_ID */        WINED3DSPR_FORKINSTID,
-    /* UNKNOWN */                                ~0u,
+    /* WINED3D_SM5_RT_JOIN_INSTANCE_ID */        WINED3DSPR_JOININSTID,
     /* WINED3D_SM5_RT_INPUT_CONTROL_POINT */     WINED3DSPR_INCONTROLPOINT,
     /* WINED3D_SM5_RT_OUTPUT_CONTROL_POINT */    WINED3DSPR_OUTCONTROLPOINT,
     /* WINED3D_SM5_RT_PATCH_CONSTANT_DATA */     WINED3DSPR_PATCHCONST,
diff --git a/dlls/wined3d/wined3d_private.h b/dlls/wined3d/wined3d_private.h
index 5d106df7af2..a6e6f3e2f58 100644
--- a/dlls/wined3d/wined3d_private.h
+++ b/dlls/wined3d/wined3d_private.h
@@ -382,6 +382,7 @@ enum wined3d_shader_register_type
     WINED3DSPR_UAV,
     WINED3DSPR_OUTPOINTID,
     WINED3DSPR_FORKINSTID,
+    WINED3DSPR_JOININSTID,
     WINED3DSPR_INCONTROLPOINT,
     WINED3DSPR_OUTCONTROLPOINT,
     WINED3DSPR_PATCHCONST,