st/mesa: only expose ARB_shader_bit_encoding with GLSL 1.3
[mesa.git] / src / mesa / state_tracker / st_program.c
index b83c561651d4709786fd0e837f77421d9d6be4da..9f98298b4a099bd68cd111d05786427ec86dd7e2 100644 (file)
@@ -110,7 +110,8 @@ delete_fp_variant(struct st_context *st, struct st_fp_variant *fpv)
       cso_delete_fragment_shader(st->cso_context, fpv->driver_shader);
    if (fpv->parameters)
       _mesa_free_parameter_list(fpv->parameters);
-      
+   if (fpv->tgsi.tokens)
+      st_free_tokens(fpv->tgsi.tokens);
    FREE(fpv);
 }
 
@@ -244,9 +245,21 @@ st_prepare_vertex_program(struct gl_context *ctx,
             stvp->output_semantic_name[slot] = TGSI_SEMANTIC_PSIZE;
             stvp->output_semantic_index[slot] = 0;
             break;
+         case VERT_RESULT_CLIP_DIST0:
+            stvp->output_semantic_name[slot] = TGSI_SEMANTIC_CLIPDIST;
+            stvp->output_semantic_index[slot] = 0;
+            break;
+         case VERT_RESULT_CLIP_DIST1:
+            stvp->output_semantic_name[slot] = TGSI_SEMANTIC_CLIPDIST;
+            stvp->output_semantic_index[slot] = 1;
+            break;
          case VERT_RESULT_EDGE:
             assert(0);
             break;
+         case VERT_RESULT_CLIP_VERTEX:
+            stvp->output_semantic_name[slot] = TGSI_SEMANTIC_CLIPVERTEX;
+            stvp->output_semantic_index[slot] = 0;
+            break;
 
          case VERT_RESULT_TEX0:
          case VERT_RESULT_TEX1:
@@ -339,7 +352,8 @@ st_translate_vertex_program(struct st_context *st,
                                    stvp->result_to_output,
                                    stvp->output_semantic_name,
                                    stvp->output_semantic_index,
-                                   key->passthrough_edgeflags );
+                                   key->passthrough_edgeflags,
+                                   key->clamp_color);
    else
       error = st_translate_mesa_program(st->ctx,
                                         TGSI_PROCESSOR_VERTEX,
@@ -356,7 +370,8 @@ st_translate_vertex_program(struct st_context *st,
                                         stvp->result_to_output,
                                         stvp->output_semantic_name,
                                         stvp->output_semantic_index,
-                                        key->passthrough_edgeflags );
+                                        key->passthrough_edgeflags,
+                                        key->clamp_color);
 
    if (error)
       goto fail;
@@ -424,10 +439,13 @@ st_get_vp_variant(struct st_context *st,
 
 
 static unsigned
-st_translate_interp(enum glsl_interp_qualifier glsl_qual)
+st_translate_interp(enum glsl_interp_qualifier glsl_qual, bool is_color)
 {
    switch (glsl_qual) {
    case INTERP_QUALIFIER_NONE:
+      if (is_color)
+         return TGSI_INTERPOLATE_COLOR;
+      return TGSI_INTERPOLATE_PERSPECTIVE;
    case INTERP_QUALIFIER_SMOOTH:
       return TGSI_INTERPOLATE_PERSPECTIVE;
    case INTERP_QUALIFIER_FLAT:
@@ -455,6 +473,23 @@ st_translate_fragment_program(struct st_context *st,
    struct st_fp_variant *variant = CALLOC_STRUCT(st_fp_variant);
    GLboolean deleteFP = GL_FALSE;
 
+   GLuint outputMapping[FRAG_RESULT_MAX];
+   GLuint inputMapping[FRAG_ATTRIB_MAX];
+   GLuint interpMode[PIPE_MAX_SHADER_INPUTS];  /* XXX size? */
+   GLuint attr;
+   GLbitfield64 inputsRead;
+   struct ureg_program *ureg;
+
+   GLboolean write_all = GL_FALSE;
+
+   ubyte input_semantic_name[PIPE_MAX_SHADER_INPUTS];
+   ubyte input_semantic_index[PIPE_MAX_SHADER_INPUTS];
+   uint fs_num_inputs = 0;
+
+   ubyte fs_output_semantic_name[PIPE_MAX_SHADER_OUTPUTS];
+   ubyte fs_output_semantic_index[PIPE_MAX_SHADER_OUTPUTS];
+   uint fs_num_outputs = 0;
+
    if (!variant)
       return NULL;
 
@@ -490,234 +525,230 @@ st_translate_fragment_program(struct st_context *st,
    }
 #endif
 
-   if (!stfp->tgsi.tokens) {
-      /* need to translate Mesa instructions to TGSI now */
-      GLuint outputMapping[FRAG_RESULT_MAX];
-      GLuint inputMapping[FRAG_ATTRIB_MAX];
-      GLuint interpMode[PIPE_MAX_SHADER_INPUTS];  /* XXX size? */
-      GLuint attr;
-      const GLbitfield64 inputsRead = stfp->Base.Base.InputsRead;
-      struct ureg_program *ureg;
+   if (!stfp->glsl_to_tgsi)
+      _mesa_remove_output_reads(&stfp->Base.Base, PROGRAM_OUTPUT);
 
-      GLboolean write_all = GL_FALSE;
+   /*
+    * Convert Mesa program inputs to TGSI input register semantics.
+    */
+   inputsRead = stfp->Base.Base.InputsRead;
+   for (attr = 0; attr < FRAG_ATTRIB_MAX; attr++) {
+      if ((inputsRead & BITFIELD64_BIT(attr)) != 0) {
+         const GLuint slot = fs_num_inputs++;
 
-      ubyte input_semantic_name[PIPE_MAX_SHADER_INPUTS];
-      ubyte input_semantic_index[PIPE_MAX_SHADER_INPUTS];
-      uint fs_num_inputs = 0;
+         inputMapping[attr] = slot;
 
-      ubyte fs_output_semantic_name[PIPE_MAX_SHADER_OUTPUTS];
-      ubyte fs_output_semantic_index[PIPE_MAX_SHADER_OUTPUTS];
-      uint fs_num_outputs = 0;
-      
-      if (!stfp->glsl_to_tgsi)
-         _mesa_remove_output_reads(&stfp->Base.Base, PROGRAM_OUTPUT);
+         switch (attr) {
+         case FRAG_ATTRIB_WPOS:
+            input_semantic_name[slot] = TGSI_SEMANTIC_POSITION;
+            input_semantic_index[slot] = 0;
+            interpMode[slot] = TGSI_INTERPOLATE_LINEAR;
+            break;
+         case FRAG_ATTRIB_COL0:
+            input_semantic_name[slot] = TGSI_SEMANTIC_COLOR;
+            input_semantic_index[slot] = 0;
+            interpMode[slot] = st_translate_interp(stfp->Base.InterpQualifier[attr],
+                                                   TRUE);
+            break;
+         case FRAG_ATTRIB_COL1:
+            input_semantic_name[slot] = TGSI_SEMANTIC_COLOR;
+            input_semantic_index[slot] = 1;
+            interpMode[slot] = st_translate_interp(stfp->Base.InterpQualifier[attr],
+                                                   TRUE);
+            break;
+         case FRAG_ATTRIB_FOGC:
+            input_semantic_name[slot] = TGSI_SEMANTIC_FOG;
+            input_semantic_index[slot] = 0;
+            interpMode[slot] = TGSI_INTERPOLATE_PERSPECTIVE;
+            break;
+         case FRAG_ATTRIB_FACE:
+            input_semantic_name[slot] = TGSI_SEMANTIC_FACE;
+            input_semantic_index[slot] = 0;
+            interpMode[slot] = TGSI_INTERPOLATE_CONSTANT;
+            break;
+         case FRAG_ATTRIB_CLIP_DIST0:
+            input_semantic_name[slot] = TGSI_SEMANTIC_CLIPDIST;
+            input_semantic_index[slot] = 0;
+            interpMode[slot] = TGSI_INTERPOLATE_PERSPECTIVE;
+            break;
+         case FRAG_ATTRIB_CLIP_DIST1:
+            input_semantic_name[slot] = TGSI_SEMANTIC_CLIPDIST;
+            input_semantic_index[slot] = 1;
+            interpMode[slot] = TGSI_INTERPOLATE_PERSPECTIVE;
+            break;
+            /* In most cases, there is nothing special about these
+             * inputs, so adopt a convention to use the generic
+             * semantic name and the mesa FRAG_ATTRIB_ number as the
+             * index.
+             *
+             * All that is required is that the vertex shader labels
+             * its own outputs similarly, and that the vertex shader
+             * generates at least every output required by the
+             * fragment shader plus fixed-function hardware (such as
+             * BFC).
+             *
+             * There is no requirement that semantic indexes start at
+             * zero or be restricted to a particular range -- nobody
+             * should be building tables based on semantic index.
+             */
+         case FRAG_ATTRIB_PNTC:
+         case FRAG_ATTRIB_TEX0:
+         case FRAG_ATTRIB_TEX1:
+         case FRAG_ATTRIB_TEX2:
+         case FRAG_ATTRIB_TEX3:
+         case FRAG_ATTRIB_TEX4:
+         case FRAG_ATTRIB_TEX5:
+         case FRAG_ATTRIB_TEX6:
+         case FRAG_ATTRIB_TEX7:
+         case FRAG_ATTRIB_VAR0:
+         default:
+            /* Actually, let's try and zero-base this just for
+             * readability of the generated TGSI.
+             */
+            assert(attr >= FRAG_ATTRIB_TEX0);
+            input_semantic_index[slot] = (attr - FRAG_ATTRIB_TEX0);
+            input_semantic_name[slot] = TGSI_SEMANTIC_GENERIC;
+            if (attr == FRAG_ATTRIB_PNTC)
+               interpMode[slot] = TGSI_INTERPOLATE_LINEAR;
+            else
+               interpMode[slot] = st_translate_interp(stfp->Base.InterpQualifier[attr],
+                                                      FALSE);
+            break;
+         }
+      }
+      else {
+         inputMapping[attr] = -1;
+      }
+   }
 
-      /*
-       * Convert Mesa program inputs to TGSI input register semantics.
-       */
-      for (attr = 0; attr < FRAG_ATTRIB_MAX; attr++) {
-         if ((inputsRead & BITFIELD64_BIT(attr)) != 0) {
-            const GLuint slot = fs_num_inputs++;
+   /*
+    * Semantics and mapping for outputs
+    */
+   {
+      uint numColors = 0;
+      GLbitfield64 outputsWritten = stfp->Base.Base.OutputsWritten;
+
+      /* if z is written, emit that first */
+      if (outputsWritten & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) {
+         fs_output_semantic_name[fs_num_outputs] = TGSI_SEMANTIC_POSITION;
+         fs_output_semantic_index[fs_num_outputs] = 0;
+         outputMapping[FRAG_RESULT_DEPTH] = fs_num_outputs;
+         fs_num_outputs++;
+         outputsWritten &= ~(1 << FRAG_RESULT_DEPTH);
+      }
 
-            inputMapping[attr] = slot;
+      if (outputsWritten & BITFIELD64_BIT(FRAG_RESULT_STENCIL)) {
+         fs_output_semantic_name[fs_num_outputs] = TGSI_SEMANTIC_STENCIL;
+         fs_output_semantic_index[fs_num_outputs] = 0;
+         outputMapping[FRAG_RESULT_STENCIL] = fs_num_outputs;
+         fs_num_outputs++;
+         outputsWritten &= ~(1 << FRAG_RESULT_STENCIL);
+      }
 
+      /* handle remaining outputs (color) */
+      for (attr = 0; attr < FRAG_RESULT_MAX; attr++) {
+         if (outputsWritten & BITFIELD64_BIT(attr)) {
             switch (attr) {
-            case FRAG_ATTRIB_WPOS:
-               input_semantic_name[slot] = TGSI_SEMANTIC_POSITION;
-               input_semantic_index[slot] = 0;
-               interpMode[slot] = TGSI_INTERPOLATE_LINEAR;
-               break;
-            case FRAG_ATTRIB_COL0:
-               input_semantic_name[slot] = TGSI_SEMANTIC_COLOR;
-               input_semantic_index[slot] = 0;
-               interpMode[slot] = TGSI_INTERPOLATE_LINEAR;
-               break;
-            case FRAG_ATTRIB_COL1:
-               input_semantic_name[slot] = TGSI_SEMANTIC_COLOR;
-               input_semantic_index[slot] = 1;
-               interpMode[slot] = TGSI_INTERPOLATE_LINEAR;
+            case FRAG_RESULT_DEPTH:
+            case FRAG_RESULT_STENCIL:
+               /* handled above */
+               assert(0);
                break;
-            case FRAG_ATTRIB_FOGC:
-               input_semantic_name[slot] = TGSI_SEMANTIC_FOG;
-               input_semantic_index[slot] = 0;
-               interpMode[slot] = TGSI_INTERPOLATE_PERSPECTIVE;
-               break;
-            case FRAG_ATTRIB_FACE:
-               input_semantic_name[slot] = TGSI_SEMANTIC_FACE;
-               input_semantic_index[slot] = 0;
-               interpMode[slot] = TGSI_INTERPOLATE_CONSTANT;
-               break;
-               /* In most cases, there is nothing special about these
-                * inputs, so adopt a convention to use the generic
-                * semantic name and the mesa FRAG_ATTRIB_ number as the
-                * index. 
-                * 
-                * All that is required is that the vertex shader labels
-                * its own outputs similarly, and that the vertex shader
-                * generates at least every output required by the
-                * fragment shader plus fixed-function hardware (such as
-                * BFC).
-                * 
-                * There is no requirement that semantic indexes start at
-                * zero or be restricted to a particular range -- nobody
-                * should be building tables based on semantic index.
-                */
-            case FRAG_ATTRIB_PNTC:
-            case FRAG_ATTRIB_TEX0:
-            case FRAG_ATTRIB_TEX1:
-            case FRAG_ATTRIB_TEX2:
-            case FRAG_ATTRIB_TEX3:
-            case FRAG_ATTRIB_TEX4:
-            case FRAG_ATTRIB_TEX5:
-            case FRAG_ATTRIB_TEX6:
-            case FRAG_ATTRIB_TEX7:
-            case FRAG_ATTRIB_VAR0:
+            case FRAG_RESULT_COLOR:
+               write_all = GL_TRUE; /* fallthrough */
             default:
-               /* Actually, let's try and zero-base this just for
-                * readability of the generated TGSI.
-                */
-               assert(attr >= FRAG_ATTRIB_TEX0);
-               input_semantic_index[slot] = (attr - FRAG_ATTRIB_TEX0);
-               input_semantic_name[slot] = TGSI_SEMANTIC_GENERIC;
-               if (attr == FRAG_ATTRIB_PNTC)
-                  interpMode[slot] = TGSI_INTERPOLATE_LINEAR;
-               else
-                  interpMode[slot] = st_translate_interp(stfp->Base.InterpQualifier[attr]);
+               assert(attr == FRAG_RESULT_COLOR ||
+                      (FRAG_RESULT_DATA0 <= attr && attr < FRAG_RESULT_MAX));
+               fs_output_semantic_name[fs_num_outputs] = TGSI_SEMANTIC_COLOR;
+               fs_output_semantic_index[fs_num_outputs] = numColors;
+               outputMapping[attr] = fs_num_outputs;
+               numColors++;
                break;
             }
-         }
-         else {
-            inputMapping[attr] = -1;
-         }
-      }
 
-      /*
-       * Semantics and mapping for outputs
-       */
-      {
-         uint numColors = 0;
-         GLbitfield64 outputsWritten = stfp->Base.Base.OutputsWritten;
-
-         /* if z is written, emit that first */
-         if (outputsWritten & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) {
-            fs_output_semantic_name[fs_num_outputs] = TGSI_SEMANTIC_POSITION;
-            fs_output_semantic_index[fs_num_outputs] = 0;
-            outputMapping[FRAG_RESULT_DEPTH] = fs_num_outputs;
             fs_num_outputs++;
-            outputsWritten &= ~(1 << FRAG_RESULT_DEPTH);
-         }
-
-         if (outputsWritten & BITFIELD64_BIT(FRAG_RESULT_STENCIL)) {
-            fs_output_semantic_name[fs_num_outputs] = TGSI_SEMANTIC_STENCIL;
-            fs_output_semantic_index[fs_num_outputs] = 0;
-            outputMapping[FRAG_RESULT_STENCIL] = fs_num_outputs;
-            fs_num_outputs++;
-            outputsWritten &= ~(1 << FRAG_RESULT_STENCIL);
-         }
-
-         /* handle remaning outputs (color) */
-         for (attr = 0; attr < FRAG_RESULT_MAX; attr++) {
-            if (outputsWritten & BITFIELD64_BIT(attr)) {
-               switch (attr) {
-               case FRAG_RESULT_DEPTH:
-               case FRAG_RESULT_STENCIL:
-                  /* handled above */
-                  assert(0);
-                  break;
-               case FRAG_RESULT_COLOR:
-                  write_all = GL_TRUE; /* fallthrough */
-               default:
-                  assert(attr == FRAG_RESULT_COLOR ||
-                         (FRAG_RESULT_DATA0 <= attr && attr < FRAG_RESULT_MAX));
-                  fs_output_semantic_name[fs_num_outputs] = TGSI_SEMANTIC_COLOR;
-                  fs_output_semantic_index[fs_num_outputs] = numColors;
-                  outputMapping[attr] = fs_num_outputs;
-                  numColors++;
-                  break;
-               }
-
-               fs_num_outputs++;
-            }
          }
       }
+   }
 
-      ureg = ureg_create( TGSI_PROCESSOR_FRAGMENT );
-      if (ureg == NULL) {
-         FREE(variant);
-         return NULL;
-      }
+   ureg = ureg_create( TGSI_PROCESSOR_FRAGMENT );
+   if (ureg == NULL) {
+      FREE(variant);
+      return NULL;
+   }
 
-      if (ST_DEBUG & DEBUG_MESA) {
-         _mesa_print_program(&stfp->Base.Base);
-         _mesa_print_program_parameters(st->ctx, &stfp->Base.Base);
-         debug_printf("\n");
-      }
-      if (write_all == GL_TRUE)
-         ureg_property_fs_color0_writes_all_cbufs(ureg, 1);
+   if (ST_DEBUG & DEBUG_MESA) {
+      _mesa_print_program(&stfp->Base.Base);
+      _mesa_print_program_parameters(st->ctx, &stfp->Base.Base);
+      debug_printf("\n");
+   }
+   if (write_all == GL_TRUE)
+      ureg_property_fs_color0_writes_all_cbufs(ureg, 1);
 
-      if (stfp->Base.FragDepthLayout != FRAG_DEPTH_LAYOUT_NONE) {
-         switch (stfp->Base.FragDepthLayout) {
-         case FRAG_DEPTH_LAYOUT_ANY:
-            ureg_property_fs_depth_layout(ureg, TGSI_FS_DEPTH_LAYOUT_ANY);
-            break;
-         case FRAG_DEPTH_LAYOUT_GREATER:
-            ureg_property_fs_depth_layout(ureg, TGSI_FS_DEPTH_LAYOUT_GREATER);
-            break;
-         case FRAG_DEPTH_LAYOUT_LESS:
-            ureg_property_fs_depth_layout(ureg, TGSI_FS_DEPTH_LAYOUT_LESS);
-            break;
-         case FRAG_DEPTH_LAYOUT_UNCHANGED:
-            ureg_property_fs_depth_layout(ureg, TGSI_FS_DEPTH_LAYOUT_UNCHANGED);
-            break;
-         default:
-            assert(0);
-         }
+   if (stfp->Base.FragDepthLayout != FRAG_DEPTH_LAYOUT_NONE) {
+      switch (stfp->Base.FragDepthLayout) {
+      case FRAG_DEPTH_LAYOUT_ANY:
+         ureg_property_fs_depth_layout(ureg, TGSI_FS_DEPTH_LAYOUT_ANY);
+         break;
+      case FRAG_DEPTH_LAYOUT_GREATER:
+         ureg_property_fs_depth_layout(ureg, TGSI_FS_DEPTH_LAYOUT_GREATER);
+         break;
+      case FRAG_DEPTH_LAYOUT_LESS:
+         ureg_property_fs_depth_layout(ureg, TGSI_FS_DEPTH_LAYOUT_LESS);
+         break;
+      case FRAG_DEPTH_LAYOUT_UNCHANGED:
+         ureg_property_fs_depth_layout(ureg, TGSI_FS_DEPTH_LAYOUT_UNCHANGED);
+         break;
+      default:
+         assert(0);
       }
-
-      if (stfp->glsl_to_tgsi)
-         st_translate_program(st->ctx,
-                              TGSI_PROCESSOR_FRAGMENT,
-                              ureg,
-                              stfp->glsl_to_tgsi,
-                              &stfp->Base.Base,
-                              /* inputs */
-                              fs_num_inputs,
-                              inputMapping,
-                              input_semantic_name,
-                              input_semantic_index,
-                              interpMode,
-                              /* outputs */
-                              fs_num_outputs,
-                              outputMapping,
-                              fs_output_semantic_name,
-                              fs_output_semantic_index, FALSE );
-      else
-         st_translate_mesa_program(st->ctx,
-                                   TGSI_PROCESSOR_FRAGMENT,
-                                   ureg,
-                                   &stfp->Base.Base,
-                                   /* inputs */
-                                   fs_num_inputs,
-                                   inputMapping,
-                                   input_semantic_name,
-                                   input_semantic_index,
-                                   interpMode,
-                                   /* outputs */
-                                   fs_num_outputs,
-                                   outputMapping,
-                                   fs_output_semantic_name,
-                                   fs_output_semantic_index, FALSE );
-
-      stfp->tgsi.tokens = ureg_get_tokens( ureg, NULL );
-      ureg_destroy( ureg );
    }
 
+   if (stfp->glsl_to_tgsi)
+      st_translate_program(st->ctx,
+                           TGSI_PROCESSOR_FRAGMENT,
+                           ureg,
+                           stfp->glsl_to_tgsi,
+                           &stfp->Base.Base,
+                           /* inputs */
+                           fs_num_inputs,
+                           inputMapping,
+                           input_semantic_name,
+                           input_semantic_index,
+                           interpMode,
+                           /* outputs */
+                           fs_num_outputs,
+                           outputMapping,
+                           fs_output_semantic_name,
+                           fs_output_semantic_index, FALSE,
+                           key->clamp_color );
+   else
+      st_translate_mesa_program(st->ctx,
+                                TGSI_PROCESSOR_FRAGMENT,
+                                ureg,
+                                &stfp->Base.Base,
+                                /* inputs */
+                                fs_num_inputs,
+                                inputMapping,
+                                input_semantic_name,
+                                input_semantic_index,
+                                interpMode,
+                                /* outputs */
+                                fs_num_outputs,
+                                outputMapping,
+                                fs_output_semantic_name,
+                                fs_output_semantic_index, FALSE,
+                                key->clamp_color);
+
+   variant->tgsi.tokens = ureg_get_tokens( ureg, NULL );
+   ureg_destroy( ureg );
+
    /* fill in variant */
-   variant->driver_shader = pipe->create_fs_state(pipe, &stfp->tgsi);
+   variant->driver_shader = pipe->create_fs_state(pipe, &variant->tgsi);
    variant->key = *key;
 
    if (ST_DEBUG & DEBUG_TGSI) {
-      tgsi_dump( stfp->tgsi.tokens, 0/*TGSI_DUMP_VERBOSE*/ );
+      tgsi_dump( variant->tgsi.tokens, 0/*TGSI_DUMP_VERBOSE*/ );
       debug_printf("\n");
    }
 
@@ -774,7 +805,7 @@ st_translate_geometry_program(struct st_context *st,
    GLuint outputMapping[GEOM_RESULT_MAX];
    struct pipe_context *pipe = st->pipe;
    GLuint attr;
-   const GLbitfield64 inputsRead = stgp->Base.Base.InputsRead;
+   GLbitfield64 inputsRead;
    GLuint vslot = 0;
    GLuint num_generic = 0;
 
@@ -814,6 +845,7 @@ st_translate_geometry_program(struct st_context *st,
    /*
     * Convert Mesa program inputs to TGSI input register semantics.
     */
+   inputsRead = stgp->Base.Base.InputsRead;
    for (attr = 0; attr < GEOM_ATTRIB_MAX; attr++) {
       if ((inputsRead & BITFIELD64_BIT(attr)) != 0) {
          const GLuint slot = gs_num_inputs;
@@ -994,6 +1026,7 @@ st_translate_geometry_program(struct st_context *st,
                              outputMapping,
                              gs_output_semantic_name,
                              gs_output_semantic_index,
+                             FALSE,
                              FALSE);
 
    stgp->num_inputs = gs_num_inputs;
@@ -1252,3 +1285,26 @@ st_destroy_program_variants(struct st_context *st)
    _mesa_HashWalk(st->ctx->Shared->ShaderObjects,
                   destroy_shader_program_variants_cb, st);
 }
+
+
+/**
+ * For debugging, print/dump the current vertex program.
+ */
+void
+st_print_current_vertex_program(void)
+{
+   GET_CURRENT_CONTEXT(ctx);
+
+   if (ctx->VertexProgram._Current) {
+      struct st_vertex_program *stvp =
+         (struct st_vertex_program *) ctx->VertexProgram._Current;
+      struct st_vp_variant *stv;
+
+      debug_printf("Vertex program %u\n", stvp->Base.Base.Id);
+
+      for (stv = stvp->variants; stv; stv = stv->next) {
+         debug_printf("variant %p\n", stv);
+         tgsi_dump(stv->tgsi.tokens, 0);
+      }
+   }
+}