diff --git a/libs/vkd3d-shader/ir.c b/libs/vkd3d-shader/ir.c
index c3bcf9058..8e58ce581 100644
--- a/libs/vkd3d-shader/ir.c
+++ b/libs/vkd3d-shader/ir.c
@@ -9592,7 +9592,7 @@ static void vsir_validate_register(struct validation_context *ctx,
         [VKD3DSPR_LOCALTHREADINDEX] = {true, 0, VSIR_DIMENSION_VEC4},
         [VKD3DSPR_COVERAGE]         = {true, 0, VSIR_DIMENSION_VEC4},
         [VKD3DSPR_SAMPLEMASK]       = {true, 0, VSIR_DIMENSION_SCALAR},
-        [VKD3DSPR_GSINSTID]         = {true, 0, VSIR_DIMENSION_SCALAR},
+        [VKD3DSPR_GSINSTID]         = {true, 0, VSIR_DIMENSION_VEC4},
         [VKD3DSPR_DEPTHOUTGE]       = {true, 0, VSIR_DIMENSION_SCALAR},
         [VKD3DSPR_DEPTHOUTLE]       = {true, 0, VSIR_DIMENSION_SCALAR},
         [VKD3DSPR_OUTSTENCILREF]    = {true, 0, VSIR_DIMENSION_SCALAR},
diff --git a/libs/vkd3d-shader/tpf.c b/libs/vkd3d-shader/tpf.c
index bdb2083e0..ed19faf94 100644
--- a/libs/vkd3d-shader/tpf.c
+++ b/libs/vkd3d-shader/tpf.c
@@ -2237,7 +2237,6 @@ bool shader_sm4_is_scalar_register(const struct vkd3d_shader_register *reg)
         case VKD3DSPR_DEPTHOUT:
         case VKD3DSPR_DEPTHOUTGE:
         case VKD3DSPR_DEPTHOUTLE:
-        case VKD3DSPR_GSINSTID:
         case VKD3DSPR_OUTPOINTID:
         case VKD3DSPR_PRIMID:
         case VKD3DSPR_SAMPLEMASK: