gallium: add TGSI property NEXT_SHADER

Radeonsi needs to know which shader stage will execute after a shader
in order to make the best decision about which shader variant to compile
first.

This is only set for VS and TES, because we don't need it elsewhere.

VS has 3 variants:
- next shader is FS
- next shader is GS
- next shader is TCS

TES has 2 variants:
- next shader is FS
- next shader is GS

Currently, radeonsi always assumes the next shader is FS, which is suboptimal,
since st/mesa always knows which shader is next if the GLSL program is not
a "separate shader".

By default, ureg always sets "next shader is FS".

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

diff --git a/src/gallium/auxiliary/tgsi/tgsi_strings.c b/src/gallium/auxiliary/tgsi/tgsi_strings.c
index 6bd1a2e14d2796d3bba133c0f2fd960abfdcee36..ae779a8320a5d7852cb93b6498ef5a99ddc8daa0 100644 (file)
--- a/src/gallium/auxiliary/tgsi/tgsi_strings.c
+++ b/src/gallium/auxiliary/tgsi/tgsi_strings.c
@@ -145,6 +145,7 @@ const char *tgsi_property_names[TGSI_PROPERTY_COUNT] =
    "NUM_CLIPDIST_ENABLED",
    "NUM_CULLDIST_ENABLED",
    "FS_EARLY_DEPTH_STENCIL",
+   "NEXT_SHADER",
 };
 
 const char *tgsi_return_type_names[TGSI_RETURN_TYPE_COUNT] =

diff --git a/src/gallium/auxiliary/tgsi/tgsi_ureg.c b/src/gallium/auxiliary/tgsi/tgsi_ureg.c
index ab1d03458effef5665f36234615e755127fab126..0dd5ea76f3398866c15b87f04e1331f5e93f70e2 100644 (file)
--- a/src/gallium/auxiliary/tgsi/tgsi_ureg.c
+++ b/src/gallium/auxiliary/tgsi/tgsi_ureg.c
@@ -101,6 +101,7 @@ struct ureg_program
 {
    unsigned processor;
    bool supports_any_inout_decl_range;
+   int next_shader_processor;
 
    struct {
       unsigned semantic_name;
@@ -1966,6 +1967,16 @@ const struct tgsi_token *ureg_finalize( struct ureg_program *ureg )
 {
    const struct tgsi_token *tokens;
 
+   switch (ureg->processor) {
+   case TGSI_PROCESSOR_VERTEX:
+   case TGSI_PROCESSOR_TESS_EVAL:
+      ureg_property(ureg, TGSI_PROPERTY_NEXT_SHADER,
+                    ureg->next_shader_processor == -1 ?
+                       TGSI_PROCESSOR_FRAGMENT :
+                       ureg->next_shader_processor);
+      break;
+   }
+
    emit_header( ureg );
    emit_decls( ureg );
    copy_instructions( ureg );
@@ -2079,6 +2090,7 @@ ureg_create_with_screen(unsigned processor, struct pipe_screen *screen)
       screen->get_shader_param(screen,
                                util_pipe_shader_from_tgsi_processor(processor),
                                PIPE_SHADER_CAP_TGSI_ANY_INOUT_DECL_RANGE) != 0;
+   ureg->next_shader_processor = -1;
 
    for (i = 0; i < Elements(ureg->properties); i++)
       ureg->properties[i] = ~0;
@@ -2108,6 +2120,13 @@ no_ureg:
 }
 
 
+void
+ureg_set_next_shader_processor(struct ureg_program *ureg, unsigned processor)
+{
+   ureg->next_shader_processor = processor;
+}
+
+
 unsigned
 ureg_get_nr_outputs( const struct ureg_program *ureg )
 {

diff --git a/src/gallium/auxiliary/tgsi/tgsi_ureg.h b/src/gallium/auxiliary/tgsi/tgsi_ureg.h
index 04a62a6e1600cfcf6c527965230bd3dd43f3643e..74324678a9924bd97c26ff462b9449bd34abfe3e 100644 (file)
--- a/src/gallium/auxiliary/tgsi/tgsi_ureg.h
+++ b/src/gallium/auxiliary/tgsi/tgsi_ureg.h
@@ -114,6 +114,8 @@ ureg_create_shader( struct ureg_program *,
                     struct pipe_context *pipe,
                    const struct pipe_stream_output_info *so );
 
+void
+ureg_set_next_shader_processor(struct ureg_program *ureg, unsigned processor);
 
 /* Alternately, return the built token stream and hand ownership of
  * that memory to the caller:

diff --git a/src/gallium/docs/source/tgsi.rst b/src/gallium/docs/source/tgsi.rst
index af2df2251da3762c877df1e937f246b91ce0fd87..6366f7e802d687900e46773697b01ba04983f9c5 100644 (file)
--- a/src/gallium/docs/source/tgsi.rst
+++ b/src/gallium/docs/source/tgsi.rst
@@ -3213,6 +3213,14 @@ Whether depth test, stencil test, and occlusion query should run before
 the fragment shader (regardless of fragment shader side effects). Corresponds
 to GLSL early_fragment_tests.
 
+NEXT_SHADER
+"""""""""""
+
+Which shader stage will MOST LIKELY follow after this shader when the shader
+is bound. This is only a hint to the driver and doesn't have to be precise.
+Only set for VS and TES.
+
+
 Texture Sampling and Texture Formats
 ------------------------------------
 

diff --git a/src/gallium/include/pipe/p_shader_tokens.h b/src/gallium/include/pipe/p_shader_tokens.h
index 7a34841088a5bcfc5e84a791503fba7c19f3767f..5c460276d73793b5797254822a81ddd328140a74 100644 (file)
--- a/src/gallium/include/pipe/p_shader_tokens.h
+++ b/src/gallium/include/pipe/p_shader_tokens.h
@@ -278,7 +278,8 @@ union tgsi_immediate_data
 #define TGSI_PROPERTY_NUM_CLIPDIST_ENABLED   15
 #define TGSI_PROPERTY_NUM_CULLDIST_ENABLED   16
 #define TGSI_PROPERTY_FS_EARLY_DEPTH_STENCIL 17
-#define TGSI_PROPERTY_COUNT                  18
+#define TGSI_PROPERTY_NEXT_SHADER            18
+#define TGSI_PROPERTY_COUNT                  19
 
 struct tgsi_property {
    unsigned Type         : 4;  /**< TGSI_TOKEN_TYPE_PROPERTY */