svga: implement generic variable index remapping

The state tracker may generate shaders that use generic vs outputs /
fs inputs like:

DCL IN[0], GENERIC[0]
DCL IN[1], GENERIC[10]
DCL IN[2], GENERIC[11]

This patch remaps 0, 10, 11 to small integers like 1, 2, 3 so that we
stay inside the SVGA3D limit (8).

The remapping is done to both the vertex shader outputs and the
fragment shader inputs.  The same mapping must be used for a vs/fs
pair.

Note that 'union svga_compile_key' is now 'struct svga_compile_key'
because we needed to add the register remapping table.  The change in
size isn't really significant though (it's not a search key).

Also, add assertions when building up SVGA3D src/dst registers to we
don't try to store too large of value for the bitfield size.

Reviewed-by: José Fonseca <[email protected]>

1 files changed, 25 insertions, 2 deletions

diff --git a/src/gallium/drivers/svga/svga_tgsi.h b/src/gallium/drivers/svga/svga_tgsi.h
index 214e113aaaa..01367e971da 100644
--- a/src/gallium/drivers/svga/svga_tgsi.h
+++ b/src/gallium/drivers/svga/svga_tgsi.h
@@ -30,6 +30,13 @@
 
 #include "svga_hw_reg.h"
 
+
+/**
+ * We use a 32-bit mask to keep track of the generic indexes.
+ */
+#define MAX_GENERIC_VARYING 32
+
+
 struct svga_fragment_shader;
 struct svga_vertex_shader;
 struct svga_shader;
@@ -39,6 +46,7 @@ struct tgsi_token;
 
 struct svga_vs_compile_key
 {
+   unsigned fs_generic_inputs;
    unsigned zero_stride_vertex_elements;
    unsigned need_prescale:1;
    unsigned allow_psiz:1;
@@ -67,9 +75,10 @@ struct svga_fs_compile_key
    } tex[PIPE_MAX_SAMPLERS];
 };
 
-union svga_compile_key {
+struct svga_compile_key {
    struct svga_vs_compile_key vkey;
    struct svga_fs_compile_key fkey;
+   int8_t generic_remap_table[MAX_GENERIC_VARYING];
 };
 
 struct svga_shader_result
@@ -78,7 +87,7 @@ struct svga_shader_result
 
    /* Parameters used to generate this compilation result:
     */
-   union svga_compile_key key;
+   struct svga_compile_key key;
 
    /* Compiled shader tokens:
     */
@@ -140,4 +149,18 @@ svga_translate_vertex_program( const struct svga_vertex_shader *fs,
 
 void svga_destroy_shader_result( struct svga_shader_result *result );
 
+unsigned
+svga_get_generic_inputs_mask(const struct tgsi_shader_info *info);
+
+unsigned
+svga_get_generic_outputs_mask(const struct tgsi_shader_info *info);
+
+void
+svga_remap_generics(unsigned generics_mask,
+                    int8_t remap_table[MAX_GENERIC_VARYING]);
+
+int
+svga_remap_generic_index(const int8_t remap_table[MAX_GENERIC_VARYING],
+                         int generic_index);
+
 #endif