mesa: Clean up nomenclature for pipeline stages.

Previously, we had an enum called gl_shader_type which represented
pipeline stages in the order they occur in the pipeline
(i.e. MESA_SHADER_VERTEX=0, MESA_SHADER_GEOMETRY=1, etc), and several
inconsistently named functions for converting between it and other
representations:

- _mesa_shader_type_to_string: gl_shader_type -> string
- _mesa_shader_type_to_index: GLenum (GL_*_SHADER) -> gl_shader_type
- _mesa_program_target_to_index: GLenum (GL_*_PROGRAM) -> gl_shader_type
- _mesa_shader_enum_to_string: GLenum (GL_*_{SHADER,PROGRAM}) -> string

This patch tries to clean things up so that we use more consistent
terminology: the enum is now called gl_shader_stage (to emphasize that
it is in the order of pipeline stages), and the conversion functions are:

- _mesa_shader_stage_to_string: gl_shader_stage -> string
- _mesa_shader_enum_to_shader_stage: GLenum (GL_*_SHADER) -> gl_shader_stage
- _mesa_program_enum_to_shader_stage: GLenum (GL_*_PROGRAM) -> gl_shader_stage
- _mesa_progshader_enum_to_string: GLenum (GL_*_{SHADER,PROGRAM}) -> string

In addition, MESA_SHADER_TYPES has been renamed to MESA_SHADER_STAGES,
for consistency with the new name for the enum.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

v2: Also rename the "target" field of _mesa_glsl_parse_state and the
"target" parameter of _mesa_shader_stage_to_string to "stage".

Reviewed-by: Brian Paul <brianp@vmware.com>
diff --git a/src/glsl/linker.cpp b/src/glsl/linker.cpp
index a81e107..428a044 100644
--- a/src/glsl/linker.cpp
+++ b/src/glsl/linker.cpp
@@ -438,7 +438,7 @@
       if (clip_vertex.variable_found() && clip_distance.variable_found()) {
          linker_error(prog, "%s shader writes to both `gl_ClipVertex' "
                       "and `gl_ClipDistance'\n",
-                      _mesa_shader_enum_to_string(shader->Type));
+                      _mesa_progshader_enum_to_string(shader->Type));
          return;
       }
       *UsesClipDistance = clip_distance.variable_found();
@@ -786,7 +786,7 @@
 cross_validate_uniforms(struct gl_shader_program *prog)
 {
    cross_validate_globals(prog, prog->_LinkedShaders,
-                          MESA_SHADER_TYPES, true);
+                          MESA_SHADER_STAGES, true);
 }
 
 /**
@@ -797,12 +797,12 @@
 interstage_cross_validate_uniform_blocks(struct gl_shader_program *prog)
 {
    unsigned max_num_uniform_blocks = 0;
-   for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {
+   for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) {
       if (prog->_LinkedShaders[i])
 	 max_num_uniform_blocks += prog->_LinkedShaders[i]->NumUniformBlocks;
    }
 
-   for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {
+   for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) {
       struct gl_shader *sh = prog->_LinkedShaders[i];
 
       prog->UniformBlockStageIndex[i] = ralloc_array(prog, int,
@@ -1376,7 +1376,7 @@
 
    if (main == NULL) {
       linker_error(prog, "%s shader lacks `main'\n",
-		   _mesa_shader_enum_to_string(shader_list[0]->Type));
+		   _mesa_progshader_enum_to_string(shader_list[0]->Type));
       return NULL;
    }
 
@@ -1488,7 +1488,7 @@
 static void
 update_array_sizes(struct gl_shader_program *prog)
 {
-   for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {
+   for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) {
 	 if (prog->_LinkedShaders[i] == NULL)
 	    continue;
 
@@ -1511,7 +1511,7 @@
 	    continue;
 
 	 unsigned int size = var->data.max_array_access;
-	 for (unsigned j = 0; j < MESA_SHADER_TYPES; j++) {
+	 for (unsigned j = 0; j < MESA_SHADER_STAGES; j++) {
 	       if (prog->_LinkedShaders[j] == NULL)
 		  continue;
 
@@ -1899,7 +1899,7 @@
       ctx->Const.GeometryProgram.MaxTextureImageUnits,
       ctx->Const.FragmentProgram.MaxTextureImageUnits
    };
-   STATIC_ASSERT(Elements(max_samplers) == MESA_SHADER_TYPES);
+   STATIC_ASSERT(Elements(max_samplers) == MESA_SHADER_STAGES);
 
    const unsigned max_default_uniform_components[] = {
       ctx->Const.VertexProgram.MaxUniformComponents,
@@ -1907,7 +1907,7 @@
       ctx->Const.FragmentProgram.MaxUniformComponents
    };
    STATIC_ASSERT(Elements(max_default_uniform_components) ==
-                 MESA_SHADER_TYPES);
+                 MESA_SHADER_STAGES);
 
    const unsigned max_combined_uniform_components[] = {
       ctx->Const.VertexProgram.MaxCombinedUniformComponents,
@@ -1915,16 +1915,16 @@
       ctx->Const.FragmentProgram.MaxCombinedUniformComponents
    };
    STATIC_ASSERT(Elements(max_combined_uniform_components) ==
-                 MESA_SHADER_TYPES);
+                 MESA_SHADER_STAGES);
 
    const unsigned max_uniform_blocks[] = {
       ctx->Const.VertexProgram.MaxUniformBlocks,
       ctx->Const.GeometryProgram.MaxUniformBlocks,
       ctx->Const.FragmentProgram.MaxUniformBlocks
    };
-   STATIC_ASSERT(Elements(max_uniform_blocks) == MESA_SHADER_TYPES);
+   STATIC_ASSERT(Elements(max_uniform_blocks) == MESA_SHADER_STAGES);
 
-   for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {
+   for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) {
       struct gl_shader *sh = prog->_LinkedShaders[i];
 
       if (sh == NULL)
@@ -1932,7 +1932,7 @@
 
       if (sh->num_samplers > max_samplers[i]) {
 	 linker_error(prog, "Too many %s shader texture samplers",
-		      _mesa_shader_type_to_string(i));
+		      _mesa_shader_stage_to_string(i));
       }
 
       if (sh->num_uniform_components > max_default_uniform_components[i]) {
@@ -1941,11 +1941,11 @@
                            "components, but the driver will try to optimize "
                            "them out; this is non-portable out-of-spec "
 			   "behavior\n",
-                           _mesa_shader_type_to_string(i));
+                           _mesa_shader_stage_to_string(i));
          } else {
             linker_error(prog, "Too many %s shader default uniform block "
 			 "components",
-                         _mesa_shader_type_to_string(i));
+                         _mesa_shader_stage_to_string(i));
          }
       }
 
@@ -1955,19 +1955,19 @@
             linker_warning(prog, "Too many %s shader uniform components, "
                            "but the driver will try to optimize them out; "
                            "this is non-portable out-of-spec behavior\n",
-                           _mesa_shader_type_to_string(i));
+                           _mesa_shader_stage_to_string(i));
          } else {
             linker_error(prog, "Too many %s shader uniform components",
-                         _mesa_shader_type_to_string(i));
+                         _mesa_shader_stage_to_string(i));
          }
       }
    }
 
-   unsigned blocks[MESA_SHADER_TYPES] = {0};
+   unsigned blocks[MESA_SHADER_STAGES] = {0};
    unsigned total_uniform_blocks = 0;
 
    for (unsigned i = 0; i < prog->NumUniformBlocks; i++) {
-      for (unsigned j = 0; j < MESA_SHADER_TYPES; j++) {
+      for (unsigned j = 0; j < MESA_SHADER_STAGES; j++) {
 	 if (prog->UniformBlockStageIndex[j][i] != -1) {
 	    blocks[j]++;
 	    total_uniform_blocks++;
@@ -1979,10 +1979,10 @@
 		      prog->NumUniformBlocks,
 		      ctx->Const.MaxCombinedUniformBlocks);
       } else {
-	 for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {
+	 for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) {
 	    if (blocks[i] > max_uniform_blocks[i]) {
 	       linker_error(prog, "Too many %s uniform blocks (%d/%d)",
-			    _mesa_shader_type_to_string(i),
+			    _mesa_shader_stage_to_string(i),
 			    blocks[i],
 			    max_uniform_blocks[i]);
 	       break;
@@ -2010,7 +2010,7 @@
    ralloc_free(prog->UniformBlocks);
    prog->UniformBlocks = NULL;
    prog->NumUniformBlocks = 0;
-   for (int i = 0; i < MESA_SHADER_TYPES; i++) {
+   for (int i = 0; i < MESA_SHADER_STAGES; i++) {
       ralloc_free(prog->UniformBlockStageIndex[i]);
       prog->UniformBlockStageIndex[i] = NULL;
    }
@@ -2085,7 +2085,7 @@
       goto done;
    }
 
-   for (unsigned int i = 0; i < MESA_SHADER_TYPES; i++) {
+   for (unsigned int i = 0; i < MESA_SHADER_STAGES; i++) {
       if (prog->_LinkedShaders[i] != NULL)
 	 ctx->Driver.DeleteShader(ctx, prog->_LinkedShaders[i]);
 
@@ -2154,7 +2154,7 @@
 
    unsigned prev;
 
-   for (prev = 0; prev < MESA_SHADER_TYPES; prev++) {
+   for (prev = 0; prev < MESA_SHADER_STAGES; prev++) {
       if (prog->_LinkedShaders[prev] != NULL)
          break;
    }
@@ -2162,7 +2162,7 @@
    /* Validate the inputs of each stage with the output of the preceding
     * stage.
     */
-   for (unsigned i = prev + 1; i < MESA_SHADER_TYPES; i++) {
+   for (unsigned i = prev + 1; i < MESA_SHADER_STAGES; i++) {
       if (prog->_LinkedShaders[i] == NULL)
          continue;
 
@@ -2182,11 +2182,11 @@
 
    /* Cross-validate uniform blocks between shader stages */
    validate_interstage_uniform_blocks(prog, prog->_LinkedShaders,
-                                      MESA_SHADER_TYPES);
+                                      MESA_SHADER_STAGES);
    if (!prog->LinkStatus)
       goto done;
 
-   for (unsigned int i = 0; i < MESA_SHADER_TYPES; i++) {
+   for (unsigned int i = 0; i < MESA_SHADER_STAGES; i++) {
       if (prog->_LinkedShaders[i] != NULL)
          lower_named_interface_blocks(mem_ctx, prog->_LinkedShaders[i]);
    }
@@ -2211,7 +2211,7 @@
     * uniforms, and varyings.  Later optimization could possibly make
     * some of that unused.
     */
-   for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {
+   for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) {
       if (prog->_LinkedShaders[i] == NULL)
 	 continue;
 
@@ -2257,7 +2257,7 @@
    }
 
    unsigned first;
-   for (first = 0; first < MESA_SHADER_TYPES; first++) {
+   for (first = 0; first < MESA_SHADER_STAGES; first++) {
       if (prog->_LinkedShaders[first] != NULL)
 	 break;
    }
@@ -2289,7 +2289,7 @@
     * eliminated if they are (transitively) not used in a later stage.
     */
    int last, next;
-   for (last = MESA_SHADER_TYPES-1; last >= 0; last--) {
+   for (last = MESA_SHADER_STAGES-1; last >= 0; last--) {
       if (prog->_LinkedShaders[last] != NULL)
          break;
    }
@@ -2404,7 +2404,7 @@
    free(frag_shader_list);
    free(geom_shader_list);
 
-   for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {
+   for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) {
       if (prog->_LinkedShaders[i] == NULL)
 	 continue;