nir: add shader_info::xfb_strides

NIR now fully contains pipe_stream_output_info in shader_info and IO
intrinsics if lower_io_variables is true. radeonsi will not use
pipe_stream_output_info after this, and other drivers are free to follow
that.

Reviewed-by: Emma Anholt <emma@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14388>

src/compiler/shader_info.h

@@ -34,6 +34,7 @@
 extern "C" {
 #endif
 
+#define MAX_XFB_BUFFERS        4
 #define MAX_INLINABLE_UNIFORMS 4
 
 struct spirv_supported_capabilities {
@@ -231,6 +232,9 @@ typedef struct shader_info {
     */
    uint16_t workgroup_size[3];
 
+   /* Transform feedback buffer strides in dwords, max. 1K - 4. */
+   uint8_t xfb_stride[MAX_XFB_BUFFERS];
+
    uint16_t inlinable_uniform_dw_offsets[MAX_INLINABLE_UNIFORMS];
    uint8_t num_inlinable_uniforms:4;