mesa: no longer combine vertex/fragment shader parameters/uniforms

GLSL Vertex and fragment shaders now have independent parameter buffers.
A new gl_uniform_list is used to keep track of program uniforms and where
each uniform is located in each shader's parameter buffer.
This makes better use of the space in each buffer and simplifies shader linking.

4 files changed, 239 insertions, 270 deletions

diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 8e49431a8fb..50b22d25bf3 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -1868,6 +1868,7 @@ enum register_file
 /** Vertex and fragment instructions */
 struct prog_instruction;
 struct gl_program_parameter_list;
+struct gl_uniform_list;
 
 
 /**
@@ -2104,7 +2105,7 @@ struct gl_query_state
 
 
 /**
- * A GLSL shader object.
+ * A GLSL vertex or fragment shader object.
  */
 struct gl_shader
 {
@@ -2122,7 +2123,8 @@ struct gl_shader
 
 
 /**
- * A GLSL program object.  Basically a linked collection of "shaders".
+ * A GLSL program object.
+ * Basically a linked collection of vertex and fragment shaders.
  */
 struct gl_shader_program
 {
@@ -2137,7 +2139,7 @@ struct gl_shader_program
    /* post-link info: */
    struct gl_vertex_program *VertexProgram;     /**< Linked vertex program */
    struct gl_fragment_program *FragmentProgram; /**< Linked fragment prog */
-   struct gl_program_parameter_list *Uniforms; /**< Plus constants, etc */
+   struct gl_uniform_list *Uniforms;
    struct gl_program_parameter_list *Varying;
    struct gl_program_parameter_list *Attributes; /**< Vertex attributes */
    GLboolean LinkStatus;   /**< GL_LINK_STATUS */
diff --git a/src/mesa/shader/shader_api.c b/src/mesa/shader/shader_api.c
index 4cb8bb8ed1f..9c419c9903f 100644
--- a/src/mesa/shader/shader_api.c
+++ b/src/mesa/shader/shader_api.c
@@ -43,6 +43,7 @@
 #include "prog_parameter.h"
 #include "prog_print.h"
 #include "prog_statevars.h"
+#include "prog_uniform.h"
 #include "shader/shader_api.h"
 #include "shader/slang/slang_compile.h"
 #include "shader/slang/slang_link.h"
@@ -75,25 +76,25 @@ _mesa_clear_shader_program_data(GLcontext *ctx,
                                 struct gl_shader_program *shProg)
 {
    if (shProg->VertexProgram) {
-      if (shProg->VertexProgram->Base.Parameters == shProg->Uniforms) {
-         /* to prevent a double-free in the next call */
-         shProg->VertexProgram->Base.Parameters = NULL;
-      }
+      /* Set ptr to NULL since the param list is shared with the
+       * original/unlinked program.
+       */
+      shProg->VertexProgram->Base.Parameters = NULL;
       ctx->Driver.DeleteProgram(ctx, &shProg->VertexProgram->Base);
       shProg->VertexProgram = NULL;
    }
 
    if (shProg->FragmentProgram) {
-      if (shProg->FragmentProgram->Base.Parameters == shProg->Uniforms) {
-         /* to prevent a double-free in the next call */
-         shProg->FragmentProgram->Base.Parameters = NULL;
-      }
+      /* Set ptr to NULL since the param list is shared with the
+       * original/unlinked program.
+       */
+      shProg->FragmentProgram->Base.Parameters = NULL;
       ctx->Driver.DeleteProgram(ctx, &shProg->FragmentProgram->Base);
       shProg->FragmentProgram = NULL;
    }
 
    if (shProg->Uniforms) {
-      _mesa_free_parameter_list(shProg->Uniforms);
+      _mesa_free_uniform_list(shProg->Uniforms);
       shProg->Uniforms = NULL;
    }
 
@@ -673,39 +674,43 @@ _mesa_get_active_uniform(GLcontext *ctx, GLuint program, GLuint index,
                          GLsizei maxLength, GLsizei *length, GLint *size,
                          GLenum *type, GLchar *nameOut)
 {
-   struct gl_shader_program *shProg
+   const struct gl_shader_program *shProg
       = _mesa_lookup_shader_program(ctx, program);
-   GLuint ind, j;
+   const struct gl_program *prog;
+   GLint progPos;
 
    if (!shProg) {
       _mesa_error(ctx, GL_INVALID_VALUE, "glGetActiveUniform");
       return;
    }
 
-   if (!shProg->Uniforms || index >= shProg->Uniforms->NumParameters) {
+   if (!shProg->Uniforms || index >= shProg->Uniforms->NumUniforms) {
       _mesa_error(ctx, GL_INVALID_VALUE, "glGetActiveUniform(index)");
       return;
    }
 
-   ind = 0;
-   for (j = 0; j < shProg->Uniforms->NumParameters; j++) {
-      if (shProg->Uniforms->Parameters[j].Type == PROGRAM_UNIFORM ||
-          shProg->Uniforms->Parameters[j].Type == PROGRAM_SAMPLER) {
-         if (ind == index) {
-            /* found it */
-            copy_string(nameOut, maxLength, length,
-                        shProg->Uniforms->Parameters[j].Name);
-            if (size)
-               *size = shProg->Uniforms->Parameters[j].Size;
-            if (type)
-               *type = shProg->Uniforms->Parameters[j].DataType;
-            return;
-         }
-         ind++;
+   progPos = shProg->Uniforms->Uniforms[index].VertPos;
+   if (progPos >= 0) {
+      prog = &shProg->VertexProgram->Base;
+   }
+   else {
+      progPos = shProg->Uniforms->Uniforms[index].FragPos;
+      if (progPos >= 0) {
+         prog = &shProg->FragmentProgram->Base;
       }
    }
 
-   _mesa_error(ctx, GL_INVALID_VALUE, "glGetActiveUniform(index)");
+   if (!prog || progPos < 0)
+      return; /* should never happen */
+
+   if (nameOut)
+      copy_string(nameOut, maxLength, length,
+                  prog->Parameters->Parameters[progPos].Name);
+   if (size)
+      *size = prog->Parameters->Parameters[progPos].Size;
+
+   if (type)
+      *type = prog->Parameters->Parameters[progPos].DataType;
 }
 
 
@@ -792,14 +797,10 @@ _mesa_get_programiv(GLcontext *ctx, GLuint program,
                                              PROGRAM_INPUT) + 1;
       break;
    case GL_ACTIVE_UNIFORMS:
-      *params
-         = _mesa_num_parameters_of_type(shProg->Uniforms, PROGRAM_UNIFORM)
-         + _mesa_num_parameters_of_type(shProg->Uniforms, PROGRAM_SAMPLER);
+      *params = shProg->Uniforms ? shProg->Uniforms->NumUniforms : 0;
       break;
    case GL_ACTIVE_UNIFORM_MAX_LENGTH:
-      *params = MAX2(
-             _mesa_longest_parameter_name(shProg->Uniforms, PROGRAM_UNIFORM),
-             _mesa_longest_parameter_name(shProg->Uniforms, PROGRAM_SAMPLER));
+      *params = _mesa_longest_uniform_name(shProg->Uniforms);
       if (*params > 0)
          (*params)++;  /* add one for terminating zero */
       break;
@@ -896,10 +897,23 @@ _mesa_get_uniformfv(GLcontext *ctx, GLuint program, GLint location,
    struct gl_shader_program *shProg
       = _mesa_lookup_shader_program(ctx, program);
    if (shProg) {
-      GLint i;
-      if (location >= 0 && location < shProg->Uniforms->NumParameters) {
-         for (i = 0; i < shProg->Uniforms->Parameters[location].Size; i++) {
-            params[i] = shProg->Uniforms->ParameterValues[location][i];
+      if (location < shProg->Uniforms->NumUniforms) {
+         GLint progPos, i;
+         const struct gl_program *prog;
+
+         progPos = shProg->Uniforms->Uniforms[location].VertPos;
+         if (progPos >= 0) {
+            prog = &shProg->VertexProgram->Base;
+         }
+         else {
+            progPos = shProg->Uniforms->Uniforms[location].FragPos;
+            if (progPos >= 0) {
+               prog = &shProg->FragmentProgram->Base;
+            }
+         }
+
+         for (i = 0; i < prog->Parameters->Parameters[progPos].Size; i++) {
+            params[i] = prog->Parameters->ParameterValues[progPos][i];
          }
       }
       else {
@@ -920,23 +934,10 @@ _mesa_get_uniform_location(GLcontext *ctx, GLuint program, const GLchar *name)
 {
    struct gl_shader_program *shProg
       = _mesa_lookup_shader_program(ctx, program);
-   if (shProg) {
-      GLuint loc;
-      for (loc = 0; loc < shProg->Uniforms->NumParameters; loc++) {
-         const struct gl_program_parameter *u
-            = shProg->Uniforms->Parameters + loc;
-         /* XXX this is a temporary simplification / short-cut.
-          * We need to handle things like "e.c[0].b" as seen in the
-          * GLSL orange book, page 189.
-          */
-         if ((u->Type == PROGRAM_UNIFORM ||
-              u->Type == PROGRAM_SAMPLER) && !strcmp(u->Name, name)) {
-            return loc;
-         }
-      }
-   }
-   return -1;
+   if (!shProg)
+      return -1;
 
+   return _mesa_lookup_uniform(shProg->Uniforms, name);
 }
 
 
@@ -1068,6 +1069,78 @@ update_textures_used(struct gl_program *prog)
 
 
 /**
+ * Set the value of a program's uniform variable.
+ * \param program  the program whose uniform to update
+ * \param location  the location/index of the uniform
+ * \param type  the datatype of the uniform
+ * \param count  the number of uniforms to set
+ * \param elems  number of elements per uniform
+ * \param values  the new values
+ */
+static void
+set_program_uniform(GLcontext *ctx, struct gl_program *program, GLint location,
+                    GLenum type, GLint count, GLint elems, const void *values)
+{
+   if (program->Parameters->Parameters[location].Type == PROGRAM_SAMPLER) {
+      /* This controls which texture unit which is used by a sampler */
+      GLuint texUnit, sampler;
+
+      /* data type for setting samplers must be int */
+      if (type != GL_INT || count != 1) {
+         _mesa_error(ctx, GL_INVALID_OPERATION,
+                     "glUniform(only glUniform1i can be used "
+                     "to set sampler uniforms)");
+         return;
+      }
+
+      sampler = (GLuint) program->Parameters->ParameterValues[location][0];
+      texUnit = ((GLuint *) values)[0];
+
+      /* check that the sampler (tex unit index) is legal */
+      if (texUnit >= ctx->Const.MaxTextureImageUnits) {
+         _mesa_error(ctx, GL_INVALID_VALUE,
+                     "glUniform1(invalid sampler/tex unit index)");
+         return;
+      }
+
+      /* This maps a sampler to a texture unit: */
+      program->SamplerUnits[sampler] = texUnit;
+      update_textures_used(program);
+
+      FLUSH_VERTICES(ctx, _NEW_TEXTURE);
+   }
+   else {
+      /* ordinary uniform variable */
+      GLint k, i;
+
+      if (count * elems > program->Parameters->Parameters[location].Size) {
+         _mesa_error(ctx, GL_INVALID_OPERATION, "glUniform(count too large)");
+         return;
+      }
+
+      for (k = 0; k < count; k++) {
+         GLfloat *uniformVal = program->Parameters->ParameterValues[location + k];
+         if (type == GL_INT ||
+             type == GL_INT_VEC2 ||
+             type == GL_INT_VEC3 ||
+             type == GL_INT_VEC4) {
+            const GLint *iValues = ((const GLint *) values) + k * elems;
+            for (i = 0; i < elems; i++) {
+               uniformVal[i] = (GLfloat) iValues[i];
+            }
+         }
+         else {
+            const GLfloat *fValues = ((const GLfloat *) values) + k * elems;
+            for (i = 0; i < elems; i++) {
+               uniformVal[i] = fValues[i];
+            }
+         }
+      }
+   }
+}
+
+
+/**
  * Called via ctx->Driver.Uniform().
  */
 static void
@@ -1075,20 +1148,18 @@ _mesa_uniform(GLcontext *ctx, GLint location, GLsizei count,
               const GLvoid *values, GLenum type)
 {
    struct gl_shader_program *shProg = ctx->Shader.CurrentProgram;
-   GLint elems, i, k;
+   GLint elems;
 
    if (!shProg || !shProg->LinkStatus) {
       _mesa_error(ctx, GL_INVALID_OPERATION, "glUniform(program not linked)");
       return;
    }
 
-   if (location < 0 || location >= (GLint) shProg->Uniforms->NumParameters) {
+   if (location < 0 || location >= (GLint) shProg->Uniforms->NumUniforms) {
       _mesa_error(ctx, GL_INVALID_VALUE, "glUniform(location)");
       return;
    }
 
-   FLUSH_VERTICES(ctx, _NEW_PROGRAM);
-
    if (count < 0) {
       _mesa_error(ctx, GL_INVALID_VALUE, "glUniform(count < 0)");
       return;
@@ -1116,63 +1187,54 @@ _mesa_uniform(GLcontext *ctx, GLint location, GLsizei count,
       return;
    }
 
-   if (count * elems > shProg->Uniforms->Parameters[location].Size) {
-      _mesa_error(ctx, GL_INVALID_OPERATION, "glUniform(count too large)");
-      return;
-   }
-
-   if (shProg->Uniforms->Parameters[location].Type == PROGRAM_SAMPLER) {
-      /* This controls which texture unit which is used by a sampler */
-      GLuint texUnit, sampler;
-
-      /* data type for setting samplers must be int */
-      if (type != GL_INT || count != 1) {
-         _mesa_error(ctx, GL_INVALID_OPERATION,
-                     "glUniform(only glUniform1i can be used "
-                     "to set sampler uniforms)");
-         return;
-      }
-
-      sampler = (GLuint) shProg->Uniforms->ParameterValues[location][0];
-      texUnit = ((GLuint *) values)[0];
+   FLUSH_VERTICES(ctx, _NEW_PROGRAM);
 
-      /* check that the sampler (tex unit index) is legal */
-      if (texUnit >= ctx->Const.MaxTextureImageUnits) {
-         _mesa_error(ctx, GL_INVALID_VALUE,
-                     "glUniform1(invalid sampler/tex unit index)");
-         return;
+   /* A uniform var may be used by both a vertex shader and a fragment
+    * shader.  We may need to update one or both shader's uniform here:
+    */
+   if (shProg->VertexProgram) {
+      GLint loc = shProg->Uniforms->Uniforms[location].VertPos;
+      if (loc >= 0) {
+         set_program_uniform(ctx, &shProg->VertexProgram->Base,
+                             loc, type, count, elems, values);
       }
+   }
 
-      if (shProg->VertexProgram) {
-         shProg->VertexProgram->Base.SamplerUnits[sampler] = texUnit;
-         update_textures_used(&shProg->VertexProgram->Base);
-      }
-      if (shProg->FragmentProgram) {
-         shProg->FragmentProgram->Base.SamplerUnits[sampler] = texUnit;
-         update_textures_used(&shProg->FragmentProgram->Base);
+   if (shProg->FragmentProgram) {
+      GLint loc = shProg->Uniforms->Uniforms[location].FragPos;
+      if (loc >= 0) {
+         set_program_uniform(ctx, &shProg->FragmentProgram->Base,
+                             loc, type, count, elems, values);
       }
+   }
+}
 
 
-      FLUSH_VERTICES(ctx, _NEW_TEXTURE);
+static void
+set_program_uniform_matrix(GLcontext *ctx, struct gl_program *program,
+                           GLuint location, GLuint rows, GLuint cols,
+                           GLboolean transpose, const GLfloat *values)
+{
+   /*
+    * Note: the _columns_ of a matrix are stored in program registers, not
+    * the rows.
+    */
+   /* XXXX need to test 3x3 and 2x2 matrices... */
+   if (transpose) {
+      GLuint row, col;
+      for (col = 0; col < cols; col++) {
+         GLfloat *v = program->Parameters->ParameterValues[location + col];
+         for (row = 0; row < rows; row++) {
+            v[row] = values[row * cols + col];
+         }
+      }
    }
    else {
-      /* ordinary uniform variable */
-      for (k = 0; k < count; k++) {
-         GLfloat *uniformVal = shProg->Uniforms->ParameterValues[location + k];
-         if (type == GL_INT ||
-             type == GL_INT_VEC2 ||
-             type == GL_INT_VEC3 ||
-             type == GL_INT_VEC4) {
-            const GLint *iValues = ((const GLint *) values) + k * elems;
-            for (i = 0; i < elems; i++) {
-               uniformVal[i] = (GLfloat) iValues[i];
-            }
-         }
-         else {
-            const GLfloat *fValues = ((const GLfloat *) values) + k * elems;
-            for (i = 0; i < elems; i++) {
-               uniformVal[i] = fValues[i];
-            }
+      GLuint row, col;
+      for (col = 0; col < cols; col++) {
+         GLfloat *v = program->Parameters->ParameterValues[location + col];
+         for (row = 0; row < rows; row++) {
+            v[row] = values[col * rows + row];
          }
       }
    }
@@ -1193,7 +1255,7 @@ _mesa_uniform_matrix(GLcontext *ctx, GLint cols, GLint rows,
          "glUniformMatrix(program not linked)");
       return;
    }
-   if (location < 0 || location >= shProg->Uniforms->NumParameters) {
+   if (location < 0 || location >= shProg->Uniforms->NumUniforms) {
       _mesa_error(ctx, GL_INVALID_VALUE, "glUniformMatrix(location)");
       return;
    }
@@ -1204,27 +1266,19 @@ _mesa_uniform_matrix(GLcontext *ctx, GLint cols, GLint rows,
 
    FLUSH_VERTICES(ctx, _NEW_PROGRAM);
 
-   /*
-    * Note: the _columns_ of a matrix are stored in program registers, not
-    * the rows.
-    */
-   /* XXXX need to test 3x3 and 2x2 matrices... */
-   if (transpose) {
-      GLuint row, col;
-      for (col = 0; col < cols; col++) {
-         GLfloat *v = shProg->Uniforms->ParameterValues[location + col];
-         for (row = 0; row < rows; row++) {
-            v[row] = values[row * cols + col];
-         }
+   if (shProg->VertexProgram) {
+      GLint loc = shProg->Uniforms->Uniforms[location].VertPos;
+      if (loc >= 0) {
+         set_program_uniform_matrix(ctx, &shProg->VertexProgram->Base,
+                                    loc, rows, cols, transpose, values);
       }
    }
-   else {
-      GLuint row, col;
-      for (col = 0; col < cols; col++) {
-         GLfloat *v = shProg->Uniforms->ParameterValues[location + col];
-         for (row = 0; row < rows; row++) {
-            v[row] = values[col * rows + row];
-         }
+
+   if (shProg->FragmentProgram) {
+      GLint loc = shProg->Uniforms->Uniforms[location].FragPos;
+      if (loc >= 0) {
+         set_program_uniform_matrix(ctx, &shProg->FragmentProgram->Base,
+                                    loc, rows, cols, transpose, values);
       }
    }
 }
diff --git a/src/mesa/shader/slang/slang_link.c b/src/mesa/shader/slang/slang_link.c
index 390ae56aa5f..addff204218 100644
--- a/src/mesa/shader/slang/slang_link.c
+++ b/src/mesa/shader/slang/slang_link.c
@@ -37,12 +37,17 @@
 #include "shader/prog_parameter.h"
 #include "shader/prog_print.h"
 #include "shader/prog_statevars.h"
+#include "shader/prog_uniform.h"
 #include "shader/shader_api.h"
 #include "slang_link.h"
 
 
 
-
+/**
+ * Linking varying vars involves rearranging varying vars so that the
+ * vertex program's output varyings matches the order of the fragment
+ * program's input varyings.
+ */
 static GLboolean
 link_varying_vars(struct gl_shader_program *shProg, struct gl_program *prog)
 {
@@ -132,148 +137,53 @@ link_varying_vars(struct gl_shader_program *shProg, struct gl_program *prog)
 }
 
 
-static GLboolean
-is_uniform(GLuint file)
-{
-   return (file == PROGRAM_ENV_PARAM ||
-           file == PROGRAM_STATE_VAR ||
-           file == PROGRAM_NAMED_PARAM ||
-           file == PROGRAM_CONSTANT ||
-           file == PROGRAM_SAMPLER ||
-           file == PROGRAM_UNIFORM);
-}
-
-
-static GLuint shProg_NumSamplers = 0; /** XXX temporary */
-
-
-static GLboolean
-link_uniform_vars(struct gl_shader_program *shProg, struct gl_program *prog)
+/**
+ * Build the shProg->Uniforms list.
+ * This is basically a list/index of all uniforms found in either/both of
+ * the vertex and fragment shaders.
+ */
+static void
+link_uniform_vars(struct gl_shader_program *shProg,
+                  struct gl_program *prog,
+                  GLuint *numSamplers)
 {
-   GLuint *map, i;
    GLuint samplerMap[MAX_SAMPLERS];
+   GLuint i;
 
-#if 0
-   printf("================ pre link uniforms ===============\n");
-   _mesa_print_parameter_list(shProg->Uniforms);
-#endif
-
-   map = (GLuint *) malloc(prog->Parameters->NumParameters * sizeof(GLuint));
-   if (!map)
-      return GL_FALSE;
-
-   for (i = 0; i < prog->Parameters->NumParameters; /* incr below*/) {
-      /* see if this uniform is in the linked uniform list */
+   for (i = 0; i < prog->Parameters->NumParameters; i++) {
       const struct gl_program_parameter *p = prog->Parameters->Parameters + i;
-      const GLfloat *pVals = prog->Parameters->ParameterValues[i];
-      GLint j;
-      GLint size;
 
-      /* sanity check */
-      assert(is_uniform(p->Type));
-
-      /* See if this uniform is already in the linked program's list */
-      if (p->Name) {
-         /* this is a named uniform */
-         j = _mesa_lookup_parameter_index(shProg->Uniforms, -1, p->Name);
-      }
-      else {
-         /* this is an unnamed constant */
-         /*GLuint swizzle;*/
-         ASSERT(p->Type == PROGRAM_CONSTANT);
-         if (_mesa_lookup_parameter_constant(shProg->Uniforms, pVals,
-                                             p->Size, &j, NULL)) {
-            assert(j >= 0);
-         }
-         else {
-            j = -1;
-         }
-      }
-
-      if (j >= 0) {
-         /* already in linked program's list */
-         /* check size XXX check this */
-#if 0
-         assert(p->Size == shProg->Uniforms->Parameters[j].Size);
-#endif
-      }
-      else {
-         /* not already in linked list */
-         switch (p->Type) {
-         case PROGRAM_ENV_PARAM:
-            j = _mesa_add_named_parameter(shProg->Uniforms, p->Name, pVals);
-            break;
-         case PROGRAM_CONSTANT:
-            j = _mesa_add_named_constant(shProg->Uniforms, p->Name, pVals, p->Size);
-            break;
-         case PROGRAM_STATE_VAR:
-            j = _mesa_add_state_reference(shProg->Uniforms, p->StateIndexes);
-            break;
-         case PROGRAM_UNIFORM:
-            j = _mesa_add_uniform(shProg->Uniforms, p->Name, p->Size, p->DataType);
-            break;
-         case PROGRAM_SAMPLER:
-            {
-               GLuint sampNum = shProg_NumSamplers++;
-               GLuint oldSampNum;
-               j = _mesa_add_sampler(shProg->Uniforms, p->Name,
-                                     p->DataType, sampNum);
-               oldSampNum = (GLuint) prog->Parameters->ParameterValues[i][0];
-               assert(oldSampNum < MAX_SAMPLERS);
-               samplerMap[oldSampNum] = sampNum;
-            }
-            break;
-         default:
-            _mesa_problem(NULL, "bad parameter type in link_uniform_vars()");
-            return GL_FALSE;
-         }
+      /*
+       * XXX FIX NEEDED HERE
+       * We should also be adding a uniform if p->Type == PROGRAM_STATE_VAR.
+       * For example, modelview matrix, light pos, etc.
+       * Also, we need to update the state-var name-generator code to
+       * generate GLSL-style names, like "gl_LightSource[0].position".
+       * Furthermore, we'll need to fix the state-var's size/datatype info.
+       */
+
+      if (p->Type == PROGRAM_UNIFORM ||
+          p->Type == PROGRAM_SAMPLER) {
+         _mesa_append_uniform(shProg->Uniforms, p->Name, prog->Target, i);
       }
 
-      ASSERT(j >= 0);
-
-      size = p->Size;
-      while (size > 0) {
-         map[i] = j;
-         i++;
-         j++;
-         size -= 4;
+      if (p->Type == PROGRAM_SAMPLER) {
+         /* Allocate a new sampler index */
+         GLuint sampNum = *numSamplers;
+         GLuint oldSampNum = (GLuint) prog->Parameters->ParameterValues[i][0];
+         assert(oldSampNum < MAX_SAMPLERS);
+         samplerMap[oldSampNum] = sampNum;
+         (*numSamplers)++;
       }
-
    }
 
-#if 0
-   printf("================ post link uniforms ===============\n");
-   _mesa_print_parameter_list(shProg->Uniforms);
-#endif
-
-#if 0
-   {
-      GLuint i;
-      for (i = 0; i < prog->Parameters->NumParameters; i++) {
-         printf("map[%d] = %d\n", i, map[i]);
-      }
-      _mesa_print_parameter_list(shProg->Uniforms);
-   }
-#endif
 
-   /* OK, now scan the program/shader instructions looking for uniform vars,
+   /* OK, now scan the program/shader instructions looking for sampler vars,
     * replacing the old index with the new index.
     */
    prog->SamplersUsed = 0x0;
    for (i = 0; i < prog->NumInstructions; i++) {
       struct prog_instruction *inst = prog->Instructions + i;
-      GLuint j;
-
-      if (is_uniform(inst->DstReg.File)) {
-         inst->DstReg.Index = map[ inst->DstReg.Index ];
-      }
-
-      for (j = 0; j < 3; j++) {
-         if (is_uniform(inst->SrcReg[j].File)) {
-            inst->SrcReg[j].Index = map[ inst->SrcReg[j].Index ];
-         }
-      }
-
       if (_mesa_is_tex_instruction(inst->Opcode)) {
          /*
          printf("====== remap sampler from %d to %d\n",
@@ -286,9 +196,6 @@ link_uniform_vars(struct gl_shader_program *shProg, struct gl_program *prog)
       }
    }
 
-   free(map);
-
-   return GL_TRUE;
 }
 
 
@@ -476,13 +383,12 @@ _slang_link(GLcontext *ctx,
 {
    const struct gl_vertex_program *vertProg;
    const struct gl_fragment_program *fragProg;
+   GLuint numSamplers = 0;
    GLuint i;
 
-   shProg_NumSamplers = 0; /** XXX temporary */
-
    _mesa_clear_shader_program_data(ctx, shProg);
 
-   shProg->Uniforms = _mesa_new_parameter_list();
+   shProg->Uniforms = _mesa_new_uniform_list();
    shProg->Varying = _mesa_new_parameter_list();
 
    /**
@@ -519,24 +425,30 @@ _slang_link(GLcontext *ctx,
       shProg->FragmentProgram = NULL;
    }
 
+   /* link varying vars */
    if (shProg->VertexProgram)
       link_varying_vars(shProg, &shProg->VertexProgram->Base);
    if (shProg->FragmentProgram)
       link_varying_vars(shProg, &shProg->FragmentProgram->Base);
 
+   /* link uniform vars */
    if (shProg->VertexProgram)
-      link_uniform_vars(shProg, &shProg->VertexProgram->Base);
+      link_uniform_vars(shProg, &shProg->VertexProgram->Base, &numSamplers);
    if (shProg->FragmentProgram)
-      link_uniform_vars(shProg, &shProg->FragmentProgram->Base);
+      link_uniform_vars(shProg, &shProg->FragmentProgram->Base, &numSamplers);
+
+   /*_mesa_print_uniforms(shProg->Uniforms);*/
 
-   /* The vertex and fragment programs share a common set of uniforms now */
    if (shProg->VertexProgram) {
-      _mesa_free_parameter_list(shProg->VertexProgram->Base.Parameters);
-      shProg->VertexProgram->Base.Parameters = shProg->Uniforms;
+      /* Rather than cloning the parameter list here, just share it.
+       * We need to be careful _mesa_clear_shader_program_data() in
+       * to avoid double-freeing.
+       */
+      shProg->VertexProgram->Base.Parameters = vertProg->Base.Parameters;
    }
    if (shProg->FragmentProgram) {
-      _mesa_free_parameter_list(shProg->FragmentProgram->Base.Parameters);
-      shProg->FragmentProgram->Base.Parameters = shProg->Uniforms;
+      /* see comment just above */
+      shProg->FragmentProgram->Base.Parameters = fragProg->Base.Parameters;
    }
 
    if (shProg->VertexProgram) {
diff --git a/src/mesa/sources b/src/mesa/sources
index d109dce5bcc..a4e2026e4b4 100644
--- a/src/mesa/sources
+++ b/src/mesa/sources
@@ -213,6 +213,7 @@ SHADER_SOURCES = \
 	shader/prog_parameter.c \
 	shader/prog_print.c \
 	shader/prog_statevars.c \
+	shader/prog_uniform.c \
 	shader/programopt.c \
 	shader/shader_api.c \