Merge commit 'origin/gallium-0.2' into gallium-xlib-rework

Conflicts:

	progs/glsl/Makefile

10 files changed, 470 insertions, 136 deletions

diff --git a/src/mesa/shader/prog_parameter.c b/src/mesa/shader/prog_parameter.c
index e6653157d46..8ae961241f6 100644
--- a/src/mesa/shader/prog_parameter.c
+++ b/src/mesa/shader/prog_parameter.c
@@ -290,7 +290,8 @@ _mesa_use_uniform(struct gl_program_parameter_list *paramList,
    GLuint i;
    for (i = 0; i < paramList->NumParameters; i++) {
       struct gl_program_parameter *p = paramList->Parameters + i;
-      if (p->Type == PROGRAM_UNIFORM && _mesa_strcmp(p->Name, name) == 0) {
+      if ((p->Type == PROGRAM_UNIFORM || p->Type == PROGRAM_SAMPLER) &&
+          _mesa_strcmp(p->Name, name) == 0) {
          p->Used = GL_TRUE;
          /* Note that large uniforms may occupy several slots so we're
           * not done searching yet.
diff --git a/src/mesa/shader/prog_statevars.h b/src/mesa/shader/prog_statevars.h
index 72e51f40314..d5358a1d042 100644
--- a/src/mesa/shader/prog_statevars.h
+++ b/src/mesa/shader/prog_statevars.h
@@ -79,10 +79,10 @@ typedef enum gl_state_index_ {
    STATE_SHININESS,
    STATE_HALF_VECTOR,
 
-   STATE_POSITION,
-   STATE_ATTENUATION,
-   STATE_SPOT_DIRECTION,
-   STATE_SPOT_CUTOFF,
+   STATE_POSITION,       /**< xyzw = position */
+   STATE_ATTENUATION,    /**< xyz = attenuation, w = spot exponent */
+   STATE_SPOT_DIRECTION, /**< xyz = direction, w = cos(cutoff) */
+   STATE_SPOT_CUTOFF,    /**< x = cutoff, yzw = undefined */
 
    STATE_TEXGEN_EYE_S,
    STATE_TEXGEN_EYE_T,
diff --git a/src/mesa/shader/slang/library/slang_common_builtin.gc b/src/mesa/shader/slang/library/slang_common_builtin.gc
index a051c53eea3..230c57cea8d 100644
--- a/src/mesa/shader/slang/library/slang_common_builtin.gc
+++ b/src/mesa/shader/slang/library/slang_common_builtin.gc
@@ -1,8 +1,9 @@
 /*
  * Mesa 3-D graphics library
- * Version:  6.5
+ * Version:  7.3
  *
  * Copyright (C) 2006  Brian Paul   All Rights Reserved.
+ * Copyright (C) 2008  VMware, Inc.  All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
@@ -26,8 +27,9 @@
 // From Shader Spec, ver. 1.10, rev. 59
 //
 
-//bp: XXX these will probably go away since the value needs to be
-//determined at runtime and may vary from one GLcontext to another...
+// Note: the values assigned to these constants here aren't actually used.
+// They're set by the compiler according to the GL context limits.
+// See slang_simplify.c
 const int gl_MaxLights = 8;
 const int gl_MaxClipPlanes = 6;
 const int gl_MaxTextureUnits = 8;
@@ -98,6 +100,9 @@ struct gl_MaterialParameters {
 uniform gl_MaterialParameters gl_FrontMaterial;
 uniform gl_MaterialParameters gl_BackMaterial;
 
+/* NOTE: the order of these fields is significant!
+ * See the definition of the lighting state vars such as STATE_SPOT_DIRECTION.
+ */
 struct gl_LightSourceParameters {
     vec4 ambient;
     vec4 diffuse;
@@ -105,12 +110,14 @@ struct gl_LightSourceParameters {
     vec4 position;
     vec4 halfVector;
     vec3 spotDirection;
-    float spotExponent;
-    float spotCutoff;
     float spotCosCutoff;
+
     float constantAttenuation;
     float linearAttenuation;
     float quadraticAttenuation;
+    float spotExponent;
+
+    float spotCutoff;
 };
 
 uniform gl_LightSourceParameters gl_LightSource[gl_MaxLights];
diff --git a/src/mesa/shader/slang/library/slang_common_builtin_gc.h b/src/mesa/shader/slang/library/slang_common_builtin_gc.h
index 46632010815..759bf247d80 100644
--- a/src/mesa/shader/slang/library/slang_common_builtin_gc.h
+++ b/src/mesa/shader/slang/library/slang_common_builtin_gc.h
@@ -66,58 +66,58 @@
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+100,105,97,110,115,0,1,1,0,0,11,0,100,101,103,0,0,0,1,3,2,90,95,1,0,9,0,1,99,0,2,17,51,0,49,52,49,
+53,57,50,54,0,0,17,49,56,48,0,48,0,0,49,0,0,4,118,101,99,52,95,109,117,108,116,105,112,108,121,0,
+18,95,95,114,101,116,86,97,108,0,59,120,121,122,0,0,18,100,101,103,0,59,120,121,122,0,0,18,99,0,59,
+120,120,120,0,0,0,0,1,90,95,0,0,12,0,0,114,97,100,105,97,110,115,0,1,1,0,0,12,0,100,101,103,0,0,0,
+1,3,2,90,95,1,0,9,0,1,99,0,2,17,51,0,49,52,49,53,57,50,54,0,0,17,49,56,48,0,48,0,0,49,0,0,4,118,
 101,99,52,95,109,117,108,116,105,112,108,121,0,18,95,95,114,101,116,86,97,108,0,0,18,100,101,103,0,
 0,18,99,0,59,120,120,120,120,0,0,0,0,1,90,95,0,0,9,0,0,100,101,103,114,101,101,115,0,1,1,0,0,9,0,
 114,97,100,0,0,0,1,3,2,90,95,1,0,9,0,1,99,0,2,17,49,56,48,0,48,0,0,17,51,0,49,52,49,53,57,50,54,0,
diff --git a/src/mesa/shader/slang/slang_builtin.c b/src/mesa/shader/slang/slang_builtin.c
index db00c54b8a2..c0f4c79e136 100644
--- a/src/mesa/shader/slang/slang_builtin.c
+++ b/src/mesa/shader/slang/slang_builtin.c
@@ -1,8 +1,9 @@
 /*
  * Mesa 3-D graphics library
- * Version:  6.5.3
+ * Version:  7.3
  *
  * Copyright (C) 2005-2007  Brian Paul   All Rights Reserved.
+ * Copyright (C) 2008  VMware, Inc.   All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
@@ -39,6 +40,10 @@
 #include "shader/slang/slang_builtin.h"
 
 
+/** special state token (see below) */
+#define STATE_ARRAY ((gl_state_index) 0xfffff)
+
+
 /**
  * Lookup GL state given a variable name, 0, 1 or 2 indexes and a field.
  * Allocate room for the state in the given param list and return position
@@ -132,6 +137,8 @@ lookup_statevar(const char *var, GLint index1, GLint index2, const char *field,
       }
    }
    else if (strcmp(var, "gl_ClipPlane") == 0) {
+      if (index1 < 0)
+         return -1;
       tokens[0] = STATE_CLIPPLANE;
       tokens[1] = index1;
    }
@@ -196,8 +203,12 @@ lookup_statevar(const char *var, GLint index1, GLint index2, const char *field,
       }
    }
    else if (strcmp(var, "gl_LightSource") == 0) {
+      if (!field || index1 < 0)
+         return -1;
+
       tokens[0] = STATE_LIGHT;
       tokens[1] = index1;
+
       if (strcmp(field, "ambient") == 0) {
          tokens[2] = STATE_AMBIENT;
       }
@@ -272,6 +283,9 @@ lookup_statevar(const char *var, GLint index1, GLint index2, const char *field,
    }
    else if (strcmp(var, "gl_FrontLightProduct") == 0 ||
             strcmp(var, "gl_BackLightProduct") == 0) {
+      if (index1 < 0 || !field)
+         return -1;
+
       tokens[0] = STATE_LIGHTPROD;
       tokens[1] = index1; /* light number */
       if (strcmp(var, "gl_FrontLightProduct") == 0) {
@@ -294,45 +308,63 @@ lookup_statevar(const char *var, GLint index1, GLint index2, const char *field,
       }
    }
    else if (strcmp(var, "gl_TextureEnvColor") == 0) {
+      if (index1 < 0)
+         return -1;
       tokens[0] = STATE_TEXENV_COLOR;
       tokens[1] = index1;
    }
    else if (strcmp(var, "gl_EyePlaneS") == 0) {
+      if (index1 < 0)
+         return -1;
       tokens[0] = STATE_TEXGEN;
       tokens[1] = index1; /* tex unit */
       tokens[2] = STATE_TEXGEN_EYE_S;
    }
    else if (strcmp(var, "gl_EyePlaneT") == 0) {
+      if (index1 < 0)
+         return -1;
       tokens[0] = STATE_TEXGEN;
       tokens[1] = index1; /* tex unit */
       tokens[2] = STATE_TEXGEN_EYE_T;
    }
    else if (strcmp(var, "gl_EyePlaneR") == 0) {
+      if (index1 < 0)
+         return -1;
       tokens[0] = STATE_TEXGEN;
       tokens[1] = index1; /* tex unit */
       tokens[2] = STATE_TEXGEN_EYE_R;
    }
    else if (strcmp(var, "gl_EyePlaneQ") == 0) {
+      if (index1 < 0)
+         return -1;
       tokens[0] = STATE_TEXGEN;
       tokens[1] = index1; /* tex unit */
       tokens[2] = STATE_TEXGEN_EYE_Q;
    }
    else if (strcmp(var, "gl_ObjectPlaneS") == 0) {
+      if (index1 < 0)
+         return -1;
       tokens[0] = STATE_TEXGEN;
       tokens[1] = index1; /* tex unit */
       tokens[2] = STATE_TEXGEN_OBJECT_S;
    }
    else if (strcmp(var, "gl_ObjectPlaneT") == 0) {
+      if (index1 < 0)
+         return -1;
       tokens[0] = STATE_TEXGEN;
       tokens[1] = index1; /* tex unit */
       tokens[2] = STATE_TEXGEN_OBJECT_T;
    }
    else if (strcmp(var, "gl_ObjectPlaneR") == 0) {
+      if (index1 < 0)
+         return -1;
       tokens[0] = STATE_TEXGEN;
       tokens[1] = index1; /* tex unit */
       tokens[2] = STATE_TEXGEN_OBJECT_R;
    }
    else if (strcmp(var, "gl_ObjectPlaneQ") == 0) {
+      if (index1 < 0)
+         return -1;
       tokens[0] = STATE_TEXGEN;
       tokens[1] = index1; /* tex unit */
       tokens[2] = STATE_TEXGEN_OBJECT_Q;
@@ -386,13 +418,222 @@ lookup_statevar(const char *var, GLint index1, GLint index2, const char *field,
 }
 
 
+
+/**
+ * Given a variable name and datatype, emit uniform/constant buffer
+ * entries which will store that state variable.
+ * For example, if name="gl_LightSource" we'll emit 64 state variable
+ * vectors/references and return position where that data starts.  This will
+ * allow run-time array indexing into the light source array.
+ *
+ * Note that this is a recursive function.
+ *
+ * \return -1 if error, else index of start of data in the program parameter list
+ */
+static GLint
+emit_statevars(const char *name, int array_len,
+               const slang_type_specifier *type,
+               gl_state_index tokens[STATE_LENGTH],
+               struct gl_program_parameter_list *paramList)
+{
+   if (type->type == SLANG_SPEC_ARRAY) {
+      GLint i, pos;
+      assert(array_len > 0);
+      if (strcmp(name, "gl_ClipPlane") == 0) {
+         tokens[0] = STATE_CLIPPLANE;
+      }
+      else if (strcmp(name, "gl_LightSource") == 0) {
+         tokens[0] = STATE_LIGHT;
+      }
+      else if (strcmp(name, "gl_FrontLightProduct") == 0) {
+         tokens[0] = STATE_LIGHTPROD;
+         tokens[2] = 0; /* front */
+      }
+      else if (strcmp(name, "gl_BackLightProduct") == 0) {
+         tokens[0] = STATE_LIGHTPROD;
+         tokens[2] = 1; /* back */
+      }
+      else if (strcmp(name, "gl_TextureEnvColor") == 0) {
+         tokens[0] = STATE_TEXENV_COLOR;
+      }
+      else if (strcmp(name, "gl_EyePlaneS") == 0) {
+         tokens[0] = STATE_TEXGEN_EYE_S;
+      }
+      else if (strcmp(name, "gl_EyePlaneT") == 0) {
+         tokens[0] = STATE_TEXGEN_EYE_T;
+      }
+      else if (strcmp(name, "gl_EyePlaneR") == 0) {
+         tokens[0] = STATE_TEXGEN_EYE_R;
+      }
+      else if (strcmp(name, "gl_EyePlaneQ") == 0) {
+         tokens[0] = STATE_TEXGEN_EYE_Q;
+      }
+      else if (strcmp(name, "gl_ObjectPlaneS") == 0) {
+         tokens[0] = STATE_TEXGEN_OBJECT_S;
+      }
+      else if (strcmp(name, "gl_ObjectPlaneT") == 0) {
+         tokens[0] = STATE_TEXGEN_OBJECT_T;
+      }
+      else if (strcmp(name, "gl_ObjectPlaneR") == 0) {
+         tokens[0] = STATE_TEXGEN_OBJECT_R;
+      }
+      else if (strcmp(name, "gl_ObjectPlaneQ") == 0) {
+         tokens[0] = STATE_TEXGEN_OBJECT_Q;
+      }
+      else {
+         return -1; /* invalid array name */
+      }
+      for (i = 0; i < array_len; i++) {
+         GLint p;
+         tokens[1] = i;
+         p = emit_statevars(NULL, 0, type->_array, tokens, paramList);
+         if (i == 0)
+            pos = p;
+      }
+      return pos;
+   }
+   else if (type->type == SLANG_SPEC_STRUCT) {
+      const slang_variable_scope *fields = type->_struct->fields;
+      GLuint i, pos;
+      for (i = 0; i < fields->num_variables; i++) {
+         const slang_variable *var = fields->variables[i];
+         GLint p = emit_statevars(var->a_name, 0, &var->type.specifier,
+                                  tokens, paramList);
+         if (i == 0)
+            pos = p;
+      }
+      return pos;
+   }
+   else {
+      GLint pos;
+      assert(type->type == SLANG_SPEC_VEC4 ||
+             type->type == SLANG_SPEC_VEC3 ||
+             type->type == SLANG_SPEC_VEC2 ||
+             type->type == SLANG_SPEC_FLOAT ||
+             type->type == SLANG_SPEC_IVEC4 ||
+             type->type == SLANG_SPEC_IVEC3 ||
+             type->type == SLANG_SPEC_IVEC2 ||
+             type->type == SLANG_SPEC_INT);
+      if (name) {
+         GLint t;
+
+         if (tokens[0] == STATE_LIGHT)
+            t = 2;
+         else if (tokens[0] == STATE_LIGHTPROD)
+            t = 3;
+         else
+            return -1; /* invalid array name */
+
+         if (strcmp(name, "ambient") == 0) {
+            tokens[t] = STATE_AMBIENT;
+         }
+         else if (strcmp(name, "diffuse") == 0) {
+            tokens[t] = STATE_DIFFUSE;
+         }
+         else if (strcmp(name, "specular") == 0) {
+            tokens[t] = STATE_SPECULAR;
+         }
+         else if (strcmp(name, "position") == 0) {
+            tokens[t] = STATE_POSITION;
+         }
+         else if (strcmp(name, "halfVector") == 0) {
+            tokens[t] = STATE_HALF_VECTOR;
+         }
+         else if (strcmp(name, "spotDirection") == 0) {
+            tokens[t] = STATE_SPOT_DIRECTION; /* xyz components */
+         }
+         else if (strcmp(name, "spotCosCutoff") == 0) {
+            tokens[t] = STATE_SPOT_DIRECTION; /* w component */
+         }
+
+         else if (strcmp(name, "constantAttenuation") == 0) {
+            tokens[t] = STATE_ATTENUATION; /* x component */
+         }
+         else if (strcmp(name, "linearAttenuation") == 0) {
+            tokens[t] = STATE_ATTENUATION; /* y component */
+         }
+         else if (strcmp(name, "quadraticAttenuation") == 0) {
+            tokens[t] = STATE_ATTENUATION; /* z component */
+         }
+         else if (strcmp(name, "spotExponent") == 0) {
+            tokens[t] = STATE_ATTENUATION; /* w = spot exponent */
+         }
+
+         else if (strcmp(name, "spotCutoff") == 0) {
+            tokens[t] = STATE_SPOT_CUTOFF; /* x component */
+         }
+
+         else {
+            return -1; /* invalid field name */
+         }
+      }
+
+      pos = _mesa_add_state_reference(paramList, tokens);
+      return pos;
+   }
+
+   return 1;
+}
+
+
+/**
+ * Unroll the named built-in uniform variable into a sequence of state
+ * vars in the given parameter list.
+ */
+static GLint
+alloc_state_var_array(const slang_variable *var,
+                      struct gl_program_parameter_list *paramList)
+{
+   gl_state_index tokens[STATE_LENGTH];
+   GLuint i;
+   GLint pos;
+
+   /* Initialize the state tokens array.  This is very important.
+    * When we call _mesa_add_state_reference() it'll searches the parameter
+    * list to see if the given statevar token sequence is already present.
+    * This is normally a good thing since it prevents redundant values in the
+    * constant buffer.
+    *
+    * But when we're building arrays of state this can be bad.  For example,
+    * consider this fragment of GLSL code:
+    *   foo = gl_LightSource[3].diffuse;
+    *   ...
+    *   bar = gl_LightSource[i].diffuse;
+    *
+    * When we unroll the gl_LightSource array (for "bar") we want to re-emit
+    * gl_LightSource[3].diffuse and not re-use the first instance (from "foo")
+    * since that would upset the array layout.  We handle this situation by
+    * setting the last token in the state var token array to the special
+    * value STATE_ARRAY.
+    * This token will only be set for array state.  We can hijack the last
+    * element in the array for this since it's never used for light, clipplane
+    * or texture env array state.
+    */
+   for (i = 0; i < STATE_LENGTH; i++)
+      tokens[i] = 0;
+   tokens[STATE_LENGTH - 1] = STATE_ARRAY;
+
+   pos = emit_statevars(var->a_name, var->array_len, &var->type.specifier,
+                        tokens, paramList);
+
+   return pos;
+}
+
+
+
 /**
  * Allocate storage for a pre-defined uniform (a GL state variable).
  * As a memory-saving optimization, we try to only allocate storage for
  * state vars that are actually used.
- * For example, the "gl_LightSource" uniform is huge.  If we only use
- * a handful of gl_LightSource fields, we don't want to allocate storage
- * for all of gl_LightSource.
+ *
+ * Arrays such as gl_LightSource are handled specially.  For an expression
+ * like "gl_LightSource[2].diffuse", we can allocate a single uniform/constant
+ * slot and return the index.  In this case, we return direct=TRUE.
+ *
+ * Buf for something like "gl_LightSource[i].diffuse" we don't know the value
+ * of 'i' at compile time so we need to "unroll" the gl_LightSource array
+ * into a consecutive sequence of uniform/constant slots so it can be indexed
+ * at runtime.  In this case, we return direct=FALSE.
  *
  * Currently, all pre-defined uniforms are in one of these forms:
  *   var
@@ -401,52 +642,62 @@ lookup_statevar(const char *var, GLint index1, GLint index2, const char *field,
  *   var[i].field
  *   var[i][j]
  *
- * \return -1 upon error, else position in paramList of the state var/data
+ * \return -1 upon error, else position in paramList of the state variable/data
  */
 GLint
 _slang_alloc_statevar(slang_ir_node *n,
-                      struct gl_program_parameter_list *paramList)
+                      struct gl_program_parameter_list *paramList,
+                      GLboolean *direct)
 {
    slang_ir_node *n0 = n;
-   const char *field = NULL, *var;
-   GLint index1 = -1, index2 = -1, pos;
+   const char *field = NULL;
+   GLint index1 = -1, index2 = -1;
    GLuint swizzle;
 
+   *direct = GL_TRUE;
+
    if (n->Opcode == IR_FIELD) {
       field = n->Field;
       n = n->Children[0];
    }
 
    if (n->Opcode == IR_ELEMENT) {
-      /* XXX can only handle constant indexes for now */
       if (n->Children[1]->Opcode == IR_FLOAT) {
          index1 = (GLint) n->Children[1]->Value[0];
-         n = n->Children[0];
       }
       else {
-         return -1;
+         *direct = GL_FALSE;
       }
+      n = n->Children[0];
    }
 
    if (n->Opcode == IR_ELEMENT) {
       /* XXX can only handle constant indexes for now */
-      assert(n->Children[1]->Opcode == IR_FLOAT);
-      index2 = (GLint) n->Children[1]->Value[0];
+      if (n->Children[1]->Opcode == IR_FLOAT) {
+         index2 = (GLint) n->Children[1]->Value[0];
+      }
+      else {
+         *direct = GL_FALSE;
+      }
       n = n->Children[0];
    }
 
    assert(n->Opcode == IR_VAR);
-   var = (char *) n->Var->a_name;
 
-   pos = lookup_statevar(var, index1, index2, field, &swizzle, paramList);
-   assert(pos >= 0);
-   if (pos >= 0) {
-      /* newly resolved storage for the statevar/constant/uniform */
-      n0->Store->File = PROGRAM_STATE_VAR;
-      n0->Store->Index = pos;
-      n0->Store->Swizzle = swizzle;
-      n0->Store->Parent = NULL;
+   if (*direct) {
+      const char *var = (const char *) n->Var->a_name;
+      GLint pos =
+         lookup_statevar(var, index1, index2, field, &swizzle, paramList);
+      if (pos >= 0) {
+         /* newly resolved storage for the statevar/constant/uniform */
+         n0->Store->File = PROGRAM_STATE_VAR;
+         n0->Store->Index = pos;
+         n0->Store->Swizzle = swizzle;
+         n0->Store->Parent = NULL;
+         return pos;
+      }
    }
-   return pos;
-}
 
+   *direct = GL_FALSE;
+   return alloc_state_var_array(n->Var, paramList);
+}
diff --git a/src/mesa/shader/slang/slang_builtin.h b/src/mesa/shader/slang/slang_builtin.h
index 58629f4f7fe..7f6fe80fcca 100644
--- a/src/mesa/shader/slang/slang_builtin.h
+++ b/src/mesa/shader/slang/slang_builtin.h
@@ -33,7 +33,8 @@
 
 extern GLint
 _slang_alloc_statevar(slang_ir_node *n,
-                      struct gl_program_parameter_list *paramList);
+                      struct gl_program_parameter_list *paramList,
+                      GLboolean *direct);
 
 
 #endif /* SLANG_BUILTIN_H */
diff --git a/src/mesa/shader/slang/slang_codegen.c b/src/mesa/shader/slang/slang_codegen.c
index 7d764cb5c1d..66615d3afd6 100644
--- a/src/mesa/shader/slang/slang_codegen.c
+++ b/src/mesa/shader/slang/slang_codegen.c
@@ -391,7 +391,7 @@ _slang_input_index(const char *name, GLenum target, GLuint *swizzleOut)
    const struct input_info *inputs
       = (target == GL_VERTEX_PROGRAM_ARB) ? vertInputs : fragInputs;
 
-   ASSERT(MAX_TEXTURE_UNITS == 8); /* if this fails, fix vertInputs above */
+   ASSERT(MAX_TEXTURE_COORD_UNITS == 8); /* if this fails, fix vertInputs above */
 
    for (i = 0; inputs[i].Name; i++) {
       if (strcmp(inputs[i].Name, name) == 0) {
@@ -1976,7 +1976,7 @@ _slang_make_array_constructor(slang_assemble_ctx *A, slang_operation *oper)
          */
          slang_variable *p = slang_variable_scope_grow(fun->parameters);
          char name[10];
-         snprintf(name, sizeof(name), "p%d", i);
+         _mesa_snprintf(name, sizeof(name), "p%d", i);
          p->a_name = slang_atom_pool_atom(A->atoms, name);
          p->type.qualifier = SLANG_QUAL_CONST;
          p->type.specifier.type = baseType;
@@ -3323,6 +3323,22 @@ is_store_writable(const slang_assemble_ctx *A, const slang_ir_storage *store)
 
 
 /**
+ * Walk up an IR storage path to compute the final swizzle.
+ * This is used when we find an expression such as "foo.xz.yx".
+ */
+static GLuint
+root_swizzle(const slang_ir_storage *st)
+{
+   GLuint swizzle = st->Swizzle;
+   while (st->Parent) {
+      st = st->Parent;
+      swizzle = _slang_swizzle_swizzle(st->Swizzle, swizzle);
+   }
+   return swizzle;
+}
+
+
+/**
  * Generate IR tree for an assignment (=).
  */
 static slang_ir_node *
@@ -3397,9 +3413,9 @@ _slang_gen_assignment(slang_assemble_ctx * A, slang_operation *oper)
       rhs = _slang_gen_operation(A, &oper->children[1]);
       if (lhs && rhs) {
          /* convert lhs swizzle into writemask */
+         const GLuint swizzle = root_swizzle(lhs->Store);
          GLuint writemask, newSwizzle;
-         if (!swizzle_to_writemask(A, lhs->Store->Swizzle,
-                                   &writemask, &newSwizzle)) {
+         if (!swizzle_to_writemask(A, swizzle, &writemask, &newSwizzle)) {
             /* Non-simple writemask, need to swizzle right hand side in
              * order to put components into the right place.
              */
diff --git a/src/mesa/shader/slang/slang_compile.c b/src/mesa/shader/slang/slang_compile.c
index d8aefd64950..b8044b10600 100644
--- a/src/mesa/shader/slang/slang_compile.c
+++ b/src/mesa/shader/slang/slang_compile.c
@@ -1470,9 +1470,9 @@ parse_expression(slang_parse_ctx * C, slang_output_ctx * O,
                   RETURN0;
                }
                else {
+                  slang_operation array_size;
                   array_constructor = GL_TRUE;
                   /* parse the array constructor size */
-                  slang_operation array_size;
                   slang_operation_construct(&array_size);
                   if (!parse_expression(C, O, &array_size)) {
                      slang_operation_destruct(&array_size);
diff --git a/src/mesa/shader/slang/slang_emit.c b/src/mesa/shader/slang/slang_emit.c
index 6587f9cf276..d3b4e64b78d 100644
--- a/src/mesa/shader/slang/slang_emit.c
+++ b/src/mesa/shader/slang/slang_emit.c
@@ -310,24 +310,22 @@ storage_to_dst_reg(struct prog_dst_register *dst, const slang_ir_storage *st)
       dst->WriteMask = swizzle_to_writemask(swizzle);
    }
    else {
-      GLuint writemask;
       switch (size) {
       case 1:
-         writemask = WRITEMASK_X << GET_SWZ(st->Swizzle, 0);
+         dst->WriteMask = WRITEMASK_X << GET_SWZ(st->Swizzle, 0);
          break;
       case 2:
-         writemask = WRITEMASK_XY;
+         dst->WriteMask = WRITEMASK_XY;
          break;
       case 3:
-         writemask = WRITEMASK_XYZ;
+         dst->WriteMask = WRITEMASK_XYZ;
          break;
       case 4:
-         writemask = WRITEMASK_XYZW;
+         dst->WriteMask = WRITEMASK_XYZW;
          break;
       default:
          ; /* error would have been caught above */
       }
-      dst->WriteMask = writemask;
    }
 
    dst->RelAddr = relAddr;
@@ -348,6 +346,10 @@ storage_to_src_reg(struct prog_src_register *src, const slang_ir_storage *st)
    assert(index >= 0);
    while (st->Parent) {
       st = st->Parent;
+      if (st->Index < 0) {
+         /* an error should have been reported already */
+         return;
+      }
       assert(st->Index >= 0);
       index += st->Index;
       swizzle = _slang_swizzle_swizzle(fix_swizzle(st->Swizzle), swizzle);
@@ -1286,6 +1288,7 @@ emit_tex(slang_emit_info *emitInfo, slang_ir_node *n)
 
    /* Child[0] is the sampler (a uniform which'll indicate the texture unit) */
    assert(n->Children[0]->Store);
+   assert(n->Children[0]->Store->File == PROGRAM_SAMPLER);
    /* Store->Index is the sampler index */
    assert(n->Children[0]->Store->Index >= 0);
    /* Store->Size is the texture target */
@@ -1295,6 +1298,10 @@ emit_tex(slang_emit_info *emitInfo, slang_ir_node *n)
    inst->TexSrcTarget = n->Children[0]->Store->Size;
    inst->TexSrcUnit = n->Children[0]->Store->Index; /* i.e. uniform's index */
 
+   /* mark the sampler as being used */
+   _mesa_use_uniform(emitInfo->prog->Parameters,
+                     (char *) n->Children[0]->Var->a_name);
+
    return inst;
 }
 
@@ -1841,9 +1848,17 @@ emit_array_element(slang_emit_info *emitInfo, slang_ir_node *n)
          root = root->Parent;
 
       if (root->File == PROGRAM_STATE_VAR) {
-         GLint index = _slang_alloc_statevar(n, emitInfo->prog->Parameters);
-         assert(n->Store->Index == index);
-         return NULL;
+         GLboolean direct;
+         GLint index =
+            _slang_alloc_statevar(n, emitInfo->prog->Parameters, &direct);
+         if (index < 0) {
+            /* error */
+            return NULL;
+         }
+         if (direct) {
+            n->Store->Index = index;
+            return NULL; /* all done */
+         }
       }
    }
 
@@ -1967,28 +1982,30 @@ emit_struct_field(slang_emit_info *emitInfo, slang_ir_node *n)
     * space for the ones that we actually use!
     */
    if (root->File == PROGRAM_STATE_VAR) {
-      root->Index = _slang_alloc_statevar(n, emitInfo->prog->Parameters);
-      if (root->Index < 0) {
+      GLboolean direct;
+      GLint index = _slang_alloc_statevar(n, emitInfo->prog->Parameters, &direct);
+      if (index < 0) {
          slang_info_log_error(emitInfo->log, "Error parsing state variable");
          return NULL;
       }
-      return NULL;
-   }
-   else {
-      /* do codegen for struct */
-      emit(emitInfo, n->Children[0]);
-      assert(n->Children[0]->Store->Index >= 0);
+      if (direct) {
+         root->Index = index;
+         return NULL; /* all done */
+      }
    }
 
+   /* do codegen for struct */
+   emit(emitInfo, n->Children[0]);
+   assert(n->Children[0]->Store->Index >= 0);
+
+
    fieldOffset = n->Store->Index;
    fieldSize = n->Store->Size;
 
    _slang_copy_ir_storage(n->Store, n->Children[0]->Store);
 
    n->Store->Index = n->Children[0]->Store->Index + fieldOffset / 4;
-   /* XXX test this:
-   n->Store->Index += fieldOffset / 4;
-   */
+   n->Store->Size = fieldSize;
 
    switch (fieldSize) {
    case 1:
@@ -2077,9 +2094,21 @@ emit_var_ref(slang_emit_info *emitInfo, slang_ir_node *n)
    assert(n->Store->File != PROGRAM_UNDEFINED);
 
    if (n->Store->File == PROGRAM_STATE_VAR && n->Store->Index < 0) {
-      n->Store->Index = _slang_alloc_statevar(n, emitInfo->prog->Parameters);
+      GLboolean direct;
+      GLint index = _slang_alloc_statevar(n, emitInfo->prog->Parameters, &direct);
+      if (index < 0) {
+         /* error */
+         char s[100];
+         _mesa_snprintf(s, sizeof(s), "Undefined variable '%s'",
+                        (char *) n->Var->a_name);
+         slang_info_log_error(emitInfo->log, s);
+         return NULL;
+      }
+
+      n->Store->Index = index;
    }
-   else if (n->Store->File == PROGRAM_UNIFORM) {
+   else if (n->Store->File == PROGRAM_UNIFORM ||
+            n->Store->File == PROGRAM_SAMPLER) {
       /* mark var as used */
       _mesa_use_uniform(emitInfo->prog->Parameters, (char *) n->Var->a_name);
    }
diff --git a/src/mesa/shader/slang/slang_link.c b/src/mesa/shader/slang/slang_link.c
index 3e97c8672b6..3f953d86e74 100644
--- a/src/mesa/shader/slang/slang_link.c
+++ b/src/mesa/shader/slang/slang_link.c
@@ -1,8 +1,9 @@
 /*
  * Mesa 3-D graphics library
- * Version:  7.2
+ * Version:  7.3
  *
  * Copyright (C) 2008  Brian Paul   All Rights Reserved.
+ * Copyright (C) 2009  VMware, Inc.  All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
@@ -136,15 +137,15 @@ link_varying_vars(struct gl_shader_program *shProg, struct gl_program *prog)
          }
          if (!bits_agree(var->Flags, v->Flags, PROG_PARAM_BIT_CENTROID)) {
             char msg[100];
-            snprintf(msg, sizeof(msg),
-                     "centroid modifier mismatch for '%s'", var->Name);
+            _mesa_snprintf(msg, sizeof(msg),
+                           "centroid modifier mismatch for '%s'", var->Name);
             link_error(shProg, msg);
             return GL_FALSE;
          }
          if (!bits_agree(var->Flags, v->Flags, PROG_PARAM_BIT_INVARIANT)) {
             char msg[100];
-            snprintf(msg, sizeof(msg),
-                     "invariant modifier mismatch for '%s'", var->Name);
+            _mesa_snprintf(msg, sizeof(msg),
+                           "invariant modifier mismatch for '%s'", var->Name);
             link_error(shProg, msg);
             return GL_FALSE;
          }
@@ -206,13 +207,27 @@ link_varying_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.
+ *
+ * About uniforms:
+ * Each uniform has two indexes, one that points into the vertex
+ * program's parameter array and another that points into the fragment
+ * program's parameter array.  When the user changes a uniform's value
+ * we have to change the value in the vertex and/or fragment program's
+ * parameter array.
+ *
+ * This function will be called twice to set up the two uniform->parameter
+ * mappings.
+ *
+ * If a uniform is only present in the vertex program OR fragment program
+ * then the fragment/vertex parameter index, respectively, will be -1.
  */
 static GLboolean
-link_uniform_vars(struct gl_shader_program *shProg,
+link_uniform_vars(GLcontext *ctx,
+                  struct gl_shader_program *shProg,
                   struct gl_program *prog,
                   GLuint *numSamplers)
 {
-   GLuint samplerMap[MAX_SAMPLERS];
+   GLuint samplerMap[200]; /* max number of samplers declared, not used */
    GLuint i;
 
    for (i = 0; i < prog->Parameters->NumParameters; i++) {
@@ -227,30 +242,41 @@ link_uniform_vars(struct gl_shader_program *shProg,
        * Furthermore, we'll need to fix the state-var's size/datatype info.
        */
 
-      if ((p->Type == PROGRAM_UNIFORM && p->Used) ||
-          p->Type == PROGRAM_SAMPLER) {
+      if ((p->Type == PROGRAM_UNIFORM || p->Type == PROGRAM_SAMPLER)
+          && p->Used) {
+         /* add this uniform, indexing into the target's Parameters list */
          struct gl_uniform *uniform =
             _mesa_append_uniform(shProg->Uniforms, p->Name, prog->Target, i);
          if (uniform)
             uniform->Initialized = p->Initialized;
       }
 
-      if (p->Type == PROGRAM_SAMPLER) {
+      /* The samplerMap[] table we build here is used to remap/re-index
+       * sampler references by TEX instructions.
+       */
+      if (p->Type == PROGRAM_SAMPLER && p->Used) {
          /* Allocate a new sampler index */
-         GLuint sampNum = *numSamplers;
          GLuint oldSampNum = (GLuint) prog->Parameters->ParameterValues[i][0];
-         if (oldSampNum >= MAX_SAMPLERS) {
-            link_error(shProg, "Too many texture samplers");
+         GLuint newSampNum = *numSamplers;
+         if (newSampNum >= ctx->Const.MaxTextureImageUnits) {
+            char s[100];
+            sprintf(s, "Too many texture samplers (%u, max is %u)",
+                    newSampNum, ctx->Const.MaxTextureImageUnits);
+            link_error(shProg, s);
             return GL_FALSE;
          }
-         samplerMap[oldSampNum] = sampNum;
+         /* save old->new mapping in the table */
+         if (oldSampNum < Elements(samplerMap))
+            samplerMap[oldSampNum] = newSampNum;
+         /* update parameter's sampler index */
+         prog->Parameters->ParameterValues[i][0] = (GLfloat) newSampNum;
          (*numSamplers)++;
       }
    }
 
-
-   /* OK, now scan the program/shader instructions looking for sampler vars,
-    * replacing the old index with the new index.
+   /* OK, now scan the program/shader instructions looking for texture
+    * instructions using sampler vars.  Replace old sampler indexes with
+    * new ones.
     */
    prog->SamplersUsed = 0x0;
    for (i = 0; i < prog->NumInstructions; i++) {
@@ -261,10 +287,13 @@ link_uniform_vars(struct gl_shader_program *shProg,
                 inst->Sampler, map[ inst->Sampler ]);
          */
          /* here, texUnit is really samplerUnit */
-         assert(inst->TexSrcUnit < MAX_SAMPLERS);
-         inst->TexSrcUnit = samplerMap[inst->TexSrcUnit];
-         prog->SamplerTargets[inst->TexSrcUnit] = inst->TexSrcTarget;
-         prog->SamplersUsed |= (1 << inst->TexSrcUnit);
+         const GLint oldSampNum = inst->TexSrcUnit;
+         if (oldSampNum < Elements(samplerMap)) {
+            const GLuint newSampNum = samplerMap[oldSampNum];
+            inst->TexSrcUnit = newSampNum;
+            prog->SamplerTargets[newSampNum] = inst->TexSrcTarget;
+            prog->SamplersUsed |= (1 << newSampNum);
+         }
       }
    }
 
@@ -564,13 +593,13 @@ _slang_link(GLcontext *ctx,
 
    /* link uniform vars */
    if (shProg->VertexProgram) {
-      if (!link_uniform_vars(shProg, &shProg->VertexProgram->Base,
+      if (!link_uniform_vars(ctx, shProg, &shProg->VertexProgram->Base,
                              &numSamplers)) {
          return;
       }
    }
    if (shProg->FragmentProgram) {
-      if (!link_uniform_vars(shProg, &shProg->FragmentProgram->Base,
+      if (!link_uniform_vars(ctx, shProg, &shProg->FragmentProgram->Base,
                              &numSamplers)) {
          return;
       }