glsl2: Move the compiler to the subdirectory it will live in in Mesa.

1 files changed, 1178 insertions, 0 deletions

diff --git a/src/glsl/ir.h b/src/glsl/ir.h
new file mode 100644
index 0000000000..3d2c7ff5cf
--- /dev/null
+++ b/src/glsl/ir.h
@@ -0,0 +1,1178 @@
+/* -*- c++ -*- */
+/*
+ * Copyright © 2010 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#pragma once
+#ifndef IR_H
+#define IR_H
+
+#include <cstdio>
+#include <cstdlib>
+
+extern "C" {
+#include <talloc.h>
+}
+
+#include "list.h"
+#include "ir_visitor.h"
+#include "ir_hierarchical_visitor.h"
+
+#ifndef ARRAY_SIZE
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof(x[0]))
+#endif
+
+struct ir_program {
+   void *bong_hits;
+};
+
+/**
+ * Base class of all IR instructions
+ */
+class ir_instruction : public exec_node {
+public:
+   const struct glsl_type *type;
+
+   class ir_constant *constant_expression_value();
+
+   /** ir_print_visitor helper for debugging. */
+   void print(void) const;
+
+   virtual void accept(ir_visitor *) = 0;
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *) = 0;
+   virtual ir_instruction *clone(struct hash_table *ht) const = 0;
+
+   /**
+    * \name IR instruction downcast functions
+    *
+    * These functions either cast the object to a derived class or return
+    * \c NULL if the object's type does not match the specified derived class.
+    * Additional downcast functions will be added as needed.
+    */
+   /*@{*/
+   virtual class ir_variable *          as_variable()         { return NULL; }
+   virtual class ir_function *          as_function()         { return NULL; }
+   virtual class ir_dereference *       as_dereference()      { return NULL; }
+   virtual class ir_dereference_array *	as_dereference_array() { return NULL; }
+   virtual class ir_rvalue *            as_rvalue()           { return NULL; }
+   virtual class ir_loop *              as_loop()             { return NULL; }
+   virtual class ir_assignment *        as_assignment()       { return NULL; }
+   virtual class ir_call *              as_call()             { return NULL; }
+   virtual class ir_return *            as_return()           { return NULL; }
+   virtual class ir_if *                as_if()               { return NULL; }
+   virtual class ir_swizzle *           as_swizzle()          { return NULL; }
+   virtual class ir_constant *          as_constant()         { return NULL; }
+   /*@}*/
+
+protected:
+   ir_instruction()
+   {
+      /* empty */
+   }
+};
+
+
+class ir_rvalue : public ir_instruction {
+public:
+   virtual ir_rvalue * as_rvalue()
+   {
+      return this;
+   }
+
+   virtual bool is_lvalue()
+   {
+      return false;
+   }
+
+   /**
+    * Get the variable that is ultimately referenced by an r-value
+    */
+   virtual ir_variable *variable_referenced()
+   {
+      return NULL;
+   }
+
+
+   /**
+    * If an r-value is a reference to a whole variable, get that variable
+    *
+    * \return
+    * Pointer to a variable that is completely dereferenced by the r-value.  If
+    * the r-value is not a dereference or the dereference does not access the
+    * entire variable (i.e., it's just one array element, struct field), \c NULL
+    * is returned.
+    */
+   virtual ir_variable *whole_variable_referenced()
+   {
+      return NULL;
+   }
+
+protected:
+   ir_rvalue()
+   {
+      /* empty */
+   }
+};
+
+
+enum ir_variable_mode {
+   ir_var_auto = 0,
+   ir_var_uniform,
+   ir_var_in,
+   ir_var_out,
+   ir_var_inout
+};
+
+enum ir_variable_interpolation {
+   ir_var_smooth = 0,
+   ir_var_flat,
+   ir_var_noperspective
+};
+
+
+class ir_variable : public ir_instruction {
+public:
+   ir_variable(const struct glsl_type *, const char *);
+
+   virtual ir_instruction *clone(struct hash_table *ht) const;
+
+   virtual ir_variable *as_variable()
+   {
+      return this;
+   }
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+
+   /**
+    * Get the string value for the interpolation qualifier
+    *
+    * \return
+    * If none of \c shader_in or \c shader_out is set, an empty string will
+    * be returned.  Otherwise the string that would be used in a shader to
+    * specify \c mode will be returned.
+    */
+   const char *interpolation_string() const;
+
+   /**
+    * Calculate the number of slots required to hold this variable
+    *
+    * This is used to determine how many uniform or varying locations a variable
+    * occupies.  The count is in units of floating point components.
+    */
+   unsigned component_slots() const;
+
+   const char *name;
+
+   /**
+    * Highest element accessed with a constant expression array index
+    *
+    * Not used for non-array variables.
+    */
+   unsigned max_array_access;
+
+   unsigned read_only:1;
+   unsigned centroid:1;
+   unsigned invariant:1;
+   /** If the variable is initialized outside of the scope of the shader */
+   unsigned shader_in:1;
+   /**
+    * If the variable value is later used outside of the scope of the shader.
+    */
+   unsigned shader_out:1;
+
+   unsigned mode:3;
+   unsigned interpolation:2;
+
+   /**
+    * Flag that the whole array is assignable
+    *
+    * In GLSL 1.20 and later whole arrays are assignable (and comparable for
+    * equality).  This flag enables this behavior.
+    */
+   unsigned array_lvalue:1;
+
+   /**
+    * Storage location of the base of this variable
+    *
+    * The precise meaning of this field depends on the nature of the variable.
+    *
+    *   - Vertex shader input: one of the values from \c gl_vert_attrib.
+    *   - Vertex shader output: one of the values from \c gl_vert_result.
+    *   - Fragment shader input: one of the values from \c gl_frag_attrib.
+    *   - Fragment shader output: one of the values from \c gl_frag_result.
+    *   - Uniforms: Per-stage uniform slot number.
+    *   - Other: This field is not currently used.
+    *
+    * If the variable is a uniform, shader input, or shader output, and the
+    * slot has not been assigned, the value will be -1.
+    */
+   int location;
+
+   /**
+    * Emit a warning if this variable is accessed.
+    */
+   const char *warn_extension;
+
+   /**
+    * Value assigned in the initializer of a variable declared "const"
+    */
+   ir_constant *constant_value;
+};
+
+
+/*@{*/
+/**
+ * The representation of a function instance; may be the full definition or
+ * simply a prototype.
+ */
+class ir_function_signature : public ir_instruction {
+   /* An ir_function_signature will be part of the list of signatures in
+    * an ir_function.
+    */
+public:
+   ir_function_signature(const glsl_type *return_type);
+
+   virtual ir_instruction *clone(struct hash_table *ht) const;
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   /**
+    * Get the name of the function for which this is a signature
+    */
+   const char *function_name() const;
+
+   /**
+    * Check whether the qualifiers match between this signature's parameters
+    * and the supplied parameter list.  If not, returns the name of the first
+    * parameter with mismatched qualifiers (for use in error messages).
+    */
+   const char *qualifiers_match(exec_list *params);
+
+   /**
+    * Replace the current parameter list with the given one.  This is useful
+    * if the current information came from a prototype, and either has invalid
+    * or missing parameter names.
+    */
+   void replace_parameters(exec_list *new_params);
+
+   /**
+    * Function return type.
+    *
+    * \note This discards the optional precision qualifier.
+    */
+   const struct glsl_type *return_type;
+
+   /**
+    * List of ir_variable of function parameters.
+    *
+    * This represents the storage.  The paramaters passed in a particular
+    * call will be in ir_call::actual_paramaters.
+    */
+   struct exec_list parameters;
+
+   /** Whether or not this function has a body (which may be empty). */
+   unsigned is_defined:1;
+
+   /** Body of instructions in the function. */
+   struct exec_list body;
+
+private:
+   /** Function of which this signature is one overload. */
+   class ir_function *function;
+
+   friend class ir_function;
+};
+
+
+/**
+ * Header for tracking multiple overloaded functions with the same name.
+ * Contains a list of ir_function_signatures representing each of the
+ * actual functions.
+ */
+class ir_function : public ir_instruction {
+public:
+   ir_function(const char *name);
+
+   virtual ir_instruction *clone(struct hash_table *ht) const;
+
+   virtual ir_function *as_function()
+   {
+      return this;
+   }
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   void add_signature(ir_function_signature *sig)
+   {
+      sig->function = this;
+      signatures.push_tail(sig);
+   }
+
+   /**
+    * Get an iterator for the set of function signatures
+    */
+   exec_list_iterator iterator()
+   {
+      return signatures.iterator();
+   }
+
+   /**
+    * Find a signature that matches a set of actual parameters, taking implicit
+    * conversions into account.
+    */
+   const ir_function_signature *matching_signature(exec_list *actual_param);
+
+   /**
+    * Find a signature that exactly matches a set of actual parameters without
+    * any implicit type conversions.
+    */
+   ir_function_signature *exact_matching_signature(exec_list *actual_ps);
+
+   /**
+    * Name of the function.
+    */
+   const char *name;
+
+private:
+   /**
+    * List of ir_function_signature for each overloaded function with this name.
+    */
+   struct exec_list signatures;
+};
+
+inline const char *ir_function_signature::function_name() const
+{
+   return function->name;
+}
+/*@}*/
+
+
+/**
+ * IR instruction representing high-level if-statements
+ */
+class ir_if : public ir_instruction {
+public:
+   ir_if(ir_rvalue *condition)
+      : condition(condition)
+   {
+      /* empty */
+   }
+
+   virtual ir_instruction *clone(struct hash_table *ht) const;
+
+   virtual ir_if *as_if()
+   {
+      return this;
+   }
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   ir_rvalue *condition;
+   /** List of ir_instruction for the body of the then branch */
+   exec_list  then_instructions;
+   /** List of ir_instruction for the body of the else branch */
+   exec_list  else_instructions;
+};
+
+
+/**
+ * IR instruction representing a high-level loop structure.
+ */
+class ir_loop : public ir_instruction {
+public:
+   ir_loop() : from(NULL), to(NULL), increment(NULL), counter(NULL)
+   {
+      /* empty */
+   }
+
+   virtual ir_instruction *clone(struct hash_table *ht) const;
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   virtual ir_loop *as_loop()
+   {
+      return this;
+   }
+
+   /**
+    * Get an iterator for the instructions of the loop body
+    */
+   exec_list_iterator iterator()
+   {
+      return body_instructions.iterator();
+   }
+
+   /** List of ir_instruction that make up the body of the loop. */
+   exec_list body_instructions;
+
+   /**
+    * \name Loop counter and controls
+    */
+   /*@{*/
+   ir_rvalue *from;
+   ir_rvalue *to;
+   ir_rvalue *increment;
+   ir_variable *counter;
+   /*@}*/
+};
+
+
+class ir_assignment : public ir_rvalue {
+public:
+   ir_assignment(ir_rvalue *lhs, ir_rvalue *rhs, ir_rvalue *condition);
+
+   virtual ir_instruction *clone(struct hash_table *ht) const;
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   virtual ir_assignment * as_assignment()
+   {
+      return this;
+   }
+
+   /**
+    * Left-hand side of the assignment.
+    */
+   ir_rvalue *lhs;
+
+   /**
+    * Value being assigned
+    */
+   ir_rvalue *rhs;
+
+   /**
+    * Optional condition for the assignment.
+    */
+   ir_rvalue *condition;
+};
+
+/* Update ir_expression::num_operands() and operator_strs when
+ * updating this list.
+ */
+enum ir_expression_operation {
+   ir_unop_bit_not,
+   ir_unop_logic_not,
+   ir_unop_neg,
+   ir_unop_abs,
+   ir_unop_sign,
+   ir_unop_rcp,
+   ir_unop_rsq,
+   ir_unop_sqrt,
+   ir_unop_exp,
+   ir_unop_log,
+   ir_unop_exp2,
+   ir_unop_log2,
+   ir_unop_f2i,      /**< Float-to-integer conversion. */
+   ir_unop_i2f,      /**< Integer-to-float conversion. */
+   ir_unop_f2b,      /**< Float-to-boolean conversion */
+   ir_unop_b2f,      /**< Boolean-to-float conversion */
+   ir_unop_i2b,      /**< int-to-boolean conversion */
+   ir_unop_b2i,      /**< Boolean-to-int conversion */
+   ir_unop_u2f,      /**< Unsigned-to-float conversion. */
+
+   /**
+    * \name Unary floating-point rounding operations.
+    */
+   /*@{*/
+   ir_unop_trunc,
+   ir_unop_ceil,
+   ir_unop_floor,
+   /*@}*/
+
+   /**
+    * \name Trigonometric operations.
+    */
+   /*@{*/
+   ir_unop_sin,
+   ir_unop_cos,
+   /*@}*/
+
+   /**
+    * \name Partial derivatives.
+    */
+   /*@{*/
+   ir_unop_dFdx,
+   ir_unop_dFdy,
+   /*@}*/
+
+   ir_binop_add,
+   ir_binop_sub,
+   ir_binop_mul,
+   ir_binop_div,
+   ir_binop_mod,
+
+   /**
+    * \name Binary comparison operators
+    */
+   /*@{*/
+   ir_binop_less,
+   ir_binop_greater,
+   ir_binop_lequal,
+   ir_binop_gequal,
+   ir_binop_equal,
+   ir_binop_nequal,
+   /*@}*/
+
+   /**
+    * \name Bit-wise binary operations.
+    */
+   /*@{*/
+   ir_binop_lshift,
+   ir_binop_rshift,
+   ir_binop_bit_and,
+   ir_binop_bit_xor,
+   ir_binop_bit_or,
+   /*@}*/
+
+   ir_binop_logic_and,
+   ir_binop_logic_xor,
+   ir_binop_logic_or,
+
+   ir_binop_dot,
+   ir_binop_min,
+   ir_binop_max,
+
+   ir_binop_pow
+};
+
+class ir_expression : public ir_rvalue {
+public:
+   ir_expression(int op, const struct glsl_type *type,
+		 ir_rvalue *, ir_rvalue *);
+
+   virtual ir_instruction *clone(struct hash_table *ht) const;
+
+   static unsigned int get_num_operands(ir_expression_operation);
+   unsigned int get_num_operands() const
+   {
+      return get_num_operands(operation);
+   }
+
+   /**
+    * Return a string representing this expression's operator.
+    */
+   const char *operator_string();
+
+   /**
+    * Do a reverse-lookup to translate the given string into an operator.
+    */
+   static ir_expression_operation get_operator(const char *);
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   ir_expression_operation operation;
+   ir_rvalue *operands[2];
+};
+
+
+/**
+ * IR instruction representing a function call
+ */
+class ir_call : public ir_rvalue {
+public:
+   ir_call(const ir_function_signature *callee, exec_list *actual_parameters)
+      : callee(callee)
+   {
+      assert(callee->return_type != NULL);
+      type = callee->return_type;
+      actual_parameters->move_nodes_to(& this->actual_parameters);
+   }
+
+   virtual ir_instruction *clone(struct hash_table *ht) const;
+
+   virtual ir_call *as_call()
+   {
+      return this;
+   }
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   /**
+    * Get a generic ir_call object when an error occurs
+    *
+    * Any allocation will be performed with 'ctx' as talloc owner.
+    */
+   static ir_call *get_error_instruction(void *ctx);
+
+   /**
+    * Get an iterator for the set of acutal parameters
+    */
+   exec_list_iterator iterator()
+   {
+      return actual_parameters.iterator();
+   }
+
+   /**
+    * Get the name of the function being called.
+    */
+   const char *callee_name() const
+   {
+      return callee->function_name();
+   }
+
+   const ir_function_signature *get_callee()
+   {
+      return callee;
+   }
+
+   /**
+    * Generates an inline version of the function before @ir,
+    * returning the return value of the function.
+    */
+   ir_rvalue *generate_inline(ir_instruction *ir);
+
+private:
+   ir_call()
+      : callee(NULL)
+   {
+      /* empty */
+   }
+
+   const ir_function_signature *callee;
+
+   /* List of ir_rvalue of paramaters passed in this call. */
+   exec_list actual_parameters;
+};
+
+
+/**
+ * \name Jump-like IR instructions.
+ *
+ * These include \c break, \c continue, \c return, and \c discard.
+ */
+/*@{*/
+class ir_jump : public ir_instruction {
+protected:
+   ir_jump()
+   {
+      /* empty */
+   }
+};
+
+class ir_return : public ir_jump {
+public:
+   ir_return()
+      : value(NULL)
+   {
+      /* empty */
+   }
+
+   ir_return(ir_rvalue *value)
+      : value(value)
+   {
+      /* empty */
+   }
+
+   virtual ir_instruction *clone(struct hash_table *) const;
+
+   virtual ir_return *as_return()
+   {
+      return this;
+   }
+
+   ir_rvalue *get_value() const
+   {
+      return value;
+   }
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   ir_rvalue *value;
+};
+
+
+/**
+ * Jump instructions used inside loops
+ *
+ * These include \c break and \c continue.  The \c break within a loop is
+ * different from the \c break within a switch-statement.
+ *
+ * \sa ir_switch_jump
+ */
+class ir_loop_jump : public ir_jump {
+public:
+   enum jump_mode {
+      jump_break,
+      jump_continue
+   };
+
+   ir_loop_jump(jump_mode mode)
+   {
+      this->mode = mode;
+      this->loop = loop;
+   }
+
+   virtual ir_instruction *clone(struct hash_table *) const;
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   bool is_break() const
+   {
+      return mode == jump_break;
+   }
+
+   bool is_continue() const
+   {
+      return mode == jump_continue;
+   }
+
+   /** Mode selector for the jump instruction. */
+   enum jump_mode mode;
+private:
+   /** Loop containing this break instruction. */
+   ir_loop *loop;
+};
+/*@}*/
+
+
+/**
+ * Texture sampling opcodes used in ir_texture
+ */
+enum ir_texture_opcode {
+   ir_tex,		/* Regular texture look-up */
+   ir_txb,		/* Texture look-up with LOD bias */
+   ir_txl,		/* Texture look-up with explicit LOD */
+   ir_txd,		/* Texture look-up with partial derivatvies */
+   ir_txf		/* Texel fetch with explicit LOD */
+};
+
+
+/**
+ * IR instruction to sample a texture
+ *
+ * The specific form of the IR instruction depends on the \c mode value
+ * selected from \c ir_texture_opcodes.  In the printed IR, these will
+ * appear as:
+ *
+ *                              Texel offset
+ *                              |       Projection divisor
+ *                              |       |   Shadow comparitor
+ *                              |       |   |
+ *                              v       v   v
+ * (tex (sampler) (coordinate) (0 0 0) (1) ( ))
+ * (txb (sampler) (coordinate) (0 0 0) (1) ( ) (bias))
+ * (txl (sampler) (coordinate) (0 0 0) (1) ( ) (lod))
+ * (txd (sampler) (coordinate) (0 0 0) (1) ( ) (dPdx dPdy))
+ * (txf (sampler) (coordinate) (0 0 0)         (lod))
+ */
+class ir_texture : public ir_rvalue {
+public:
+   ir_texture(enum ir_texture_opcode op)
+      : op(op), projector(NULL), shadow_comparitor(NULL)
+   {
+      /* empty */
+   }
+
+   virtual ir_instruction *clone(struct hash_table *) const;
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   /**
+    * Return a string representing the ir_texture_opcode.
+    */
+   const char *opcode_string();
+
+   /** Set the sampler and infer the type. */
+   void set_sampler(ir_dereference *sampler);
+
+   /**
+    * Do a reverse-lookup to translate a string into an ir_texture_opcode.
+    */
+   static ir_texture_opcode get_opcode(const char *);
+
+   enum ir_texture_opcode op;
+
+   /** Sampler to use for the texture access. */
+   ir_dereference *sampler;
+
+   /** Texture coordinate to sample */
+   ir_rvalue *coordinate;
+
+   /**
+    * Value used for projective divide.
+    *
+    * If there is no projective divide (the common case), this will be
+    * \c NULL.  Optimization passes should check for this to point to a constant
+    * of 1.0 and replace that with \c NULL.
+    */
+   ir_rvalue *projector;
+
+   /**
+    * Coordinate used for comparison on shadow look-ups.
+    *
+    * If there is no shadow comparison, this will be \c NULL.  For the
+    * \c ir_txf opcode, this *must* be \c NULL.
+    */
+   ir_rvalue *shadow_comparitor;
+
+   /** Explicit texel offsets. */
+   signed char offsets[3];
+
+   union {
+      ir_rvalue *lod;		/**< Floating point LOD */
+      ir_rvalue *bias;		/**< Floating point LOD bias */
+      struct {
+	 ir_rvalue *dPdx;	/**< Partial derivative of coordinate wrt X */
+	 ir_rvalue *dPdy;	/**< Partial derivative of coordinate wrt Y */
+      } grad;
+   } lod_info;
+};
+
+
+struct ir_swizzle_mask {
+   unsigned x:2;
+   unsigned y:2;
+   unsigned z:2;
+   unsigned w:2;
+
+   /**
+    * Number of components in the swizzle.
+    */
+   unsigned num_components:3;
+
+   /**
+    * Does the swizzle contain duplicate components?
+    *
+    * L-value swizzles cannot contain duplicate components.
+    */
+   unsigned has_duplicates:1;
+};
+
+
+class ir_swizzle : public ir_rvalue {
+public:
+   ir_swizzle(ir_rvalue *, unsigned x, unsigned y, unsigned z, unsigned w,
+              unsigned count);
+   ir_swizzle(ir_rvalue *val, ir_swizzle_mask mask);
+
+   virtual ir_instruction *clone(struct hash_table *) const;
+
+   virtual ir_swizzle *as_swizzle()
+   {
+      return this;
+   }
+
+   /**
+    * Construct an ir_swizzle from the textual representation.  Can fail.
+    */
+   static ir_swizzle *create(ir_rvalue *, const char *, unsigned vector_length);
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   bool is_lvalue()
+   {
+      return val->is_lvalue() && !mask.has_duplicates;
+   }
+
+   /**
+    * Get the variable that is ultimately referenced by an r-value
+    */
+   virtual ir_variable *variable_referenced();
+
+   ir_rvalue *val;
+   ir_swizzle_mask mask;
+};
+
+
+class ir_dereference : public ir_rvalue {
+public:
+   virtual ir_dereference *as_dereference()
+   {
+      return this;
+   }
+
+   bool is_lvalue();
+
+   /**
+    * Get the variable that is ultimately referenced by an r-value
+    */
+   virtual ir_variable *variable_referenced() = 0;
+};
+
+
+class ir_dereference_variable : public ir_dereference {
+public:
+   ir_dereference_variable(ir_variable *var);
+
+   virtual ir_instruction *clone(struct hash_table *) const;
+
+   /**
+    * Get the variable that is ultimately referenced by an r-value
+    */
+   virtual ir_variable *variable_referenced()
+   {
+      return this->var;
+   }
+
+   virtual ir_variable *whole_variable_referenced()
+   {
+      /* ir_dereference_variable objects always dereference the entire
+       * variable.  However, if this dereference is dereferenced by anything
+       * else, the complete deferefernce chain is not a whole-variable
+       * dereference.  This method should only be called on the top most
+       * ir_rvalue in a dereference chain.
+       */
+      return this->var;
+   }
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   /**
+    * Object being dereferenced.
+    */
+   ir_variable *var;
+};
+
+
+class ir_dereference_array : public ir_dereference {
+public:
+   ir_dereference_array(ir_rvalue *value, ir_rvalue *array_index);
+
+   ir_dereference_array(ir_variable *var, ir_rvalue *array_index);
+
+   virtual ir_instruction *clone(struct hash_table *) const;
+
+   virtual ir_dereference_array *as_dereference_array()
+   {
+      return this;
+   }
+
+   /**
+    * Get the variable that is ultimately referenced by an r-value
+    */
+   virtual ir_variable *variable_referenced()
+   {
+      return this->array->variable_referenced();
+   }
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   ir_rvalue *array;
+   ir_rvalue *array_index;
+
+private:
+   void set_array(ir_rvalue *value);
+};
+
+
+class ir_dereference_record : public ir_dereference {
+public:
+   ir_dereference_record(ir_rvalue *value, const char *field);
+
+   ir_dereference_record(ir_variable *var, const char *field);
+
+   virtual ir_instruction *clone(struct hash_table *) const;
+
+   /**
+    * Get the variable that is ultimately referenced by an r-value
+    */
+   virtual ir_variable *variable_referenced()
+   {
+      return this->record->variable_referenced();
+   }
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   ir_rvalue *record;
+   const char *field;
+};
+
+
+/**
+ * Data stored in an ir_constant
+ */
+union ir_constant_data {
+      unsigned u[16];
+      int i[16];
+      float f[16];
+      bool b[16];
+};
+
+
+class ir_constant : public ir_rvalue {
+public:
+   ir_constant(const struct glsl_type *type, const ir_constant_data *data);
+   ir_constant(bool b);
+   ir_constant(unsigned int u);
+   ir_constant(int i);
+   ir_constant(float f);
+
+   /**
+    * Construct an ir_constant from a list of ir_constant values
+    */
+   ir_constant(const struct glsl_type *type, exec_list *values);
+
+   /**
+    * Construct an ir_constant from a scalar component of another ir_constant
+    *
+    * The new \c ir_constant inherits the type of the component from the
+    * source constant.
+    *
+    * \note
+    * In the case of a matrix constant, the new constant is a scalar, \b not
+    * a vector.
+    */
+   ir_constant(const ir_constant *c, unsigned i);
+
+   virtual ir_instruction *clone(struct hash_table *) const;
+
+   virtual ir_constant *as_constant()
+   {
+      return this;
+   }
+
+   virtual void accept(ir_visitor *v)
+   {
+      v->visit(this);
+   }
+
+   virtual ir_visitor_status accept(ir_hierarchical_visitor *);
+
+   /**
+    * Get a particular component of a constant as a specific type
+    *
+    * This is useful, for example, to get a value from an integer constant
+    * as a float or bool.  This appears frequently when constructors are
+    * called with all constant parameters.
+    */
+   /*@{*/
+   bool get_bool_component(unsigned i) const;
+   float get_float_component(unsigned i) const;
+   int get_int_component(unsigned i) const;
+   unsigned get_uint_component(unsigned i) const;
+   /*@}*/
+
+   ir_constant *get_record_field(const char *name);
+
+   /**
+    * Determine whether a constant has the same value as another constant
+    */
+   bool has_value(const ir_constant *) const;
+
+   /**
+    * Value of the constant.
+    *
+    * The field used to back the values supplied by the constant is determined
+    * by the type associated with the \c ir_instruction.  Constants may be
+    * scalars, vectors, or matrices.
+    */
+   union ir_constant_data value;
+
+   exec_list components;
+
+private:
+   /**
+    * Parameterless constructor only used by the clone method
+    */
+   ir_constant(void);
+};
+
+void
+visit_exec_list(exec_list *list, ir_visitor *visitor);
+
+void validate_ir_tree(exec_list *instructions);
+
+extern void
+_mesa_glsl_initialize_variables(exec_list *instructions,
+				struct _mesa_glsl_parse_state *state);
+
+extern void
+_mesa_glsl_initialize_functions(exec_list *instructions,
+				struct _mesa_glsl_parse_state *state);
+
+#endif /* IR_H */