gallium: add TGSI_PROPERTY_LAYER_VIEWPORT_RELATIVE

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4529>

src/gallium/auxiliary/tgsi/tgsi_strings.c

@@ -163,6 +163,7 @@ const char *tgsi_property_names[TGSI_PROPERTY_COUNT] =
    "MUL_ZERO_WINS",
    "VS_BLIT_SGPRS_AMD",
    "CS_USER_DATA_COMPONENTS_AMD",
+   "LAYER_VIEWPORT_RELATIVE",
 };
 
 const char *tgsi_return_type_names[TGSI_RETURN_TYPE_COUNT] =

src/gallium/docs/source/tgsi.rst

@@ -3804,6 +3804,13 @@ When enabled, the input for TGSI_SEMANTIC_SAMPLEMASK will exclude samples
 that have failed the depth/stencil tests. This is only valid when
 FS_EARLY_DEPTH_STENCIL is also specified.
 
+LAYER_VIEWPORT_RELATIVE
+"""""""""""""""""""""""
+
+When enabled, the TGSI_SEMATNIC_LAYER output value is relative to the
+current viewport. This is especially useful in conjunction with
+TGSI_SEMANTIC_VIEWPORT_MASK.
+
 
 Texture Sampling and Texture Formats
 ------------------------------------

src/gallium/include/pipe/p_shader_tokens.h

@@ -307,6 +307,7 @@ enum tgsi_property_name {
    TGSI_PROPERTY_MUL_ZERO_WINS,
    TGSI_PROPERTY_VS_BLIT_SGPRS_AMD,
    TGSI_PROPERTY_CS_USER_DATA_COMPONENTS_AMD,
+   TGSI_PROPERTY_LAYER_VIEWPORT_RELATIVE,
    TGSI_PROPERTY_COUNT,
 };