glsl: move to compiler/

Signed-off-by: Emil Velikov <[email protected]>
Acked-by: Matt Turner <[email protected]>
Acked-by: Jose Fonseca <[email protected]>

1 files changed, 2039 insertions, 0 deletions

diff --git a/src/compiler/glsl/ir.cpp b/src/compiler/glsl/ir.cpp
new file mode 100644
index 00000000000..de9d314bae4
--- /dev/null
+++ b/src/compiler/glsl/ir.cpp
@@ -0,0 +1,2039 @@
+/*
+ * 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.
+ */
+#include <string.h>
+#include "main/core.h" /* for MAX2 */
+#include "ir.h"
+#include "compiler/glsl_types.h"
+
+ir_rvalue::ir_rvalue(enum ir_node_type t)
+   : ir_instruction(t)
+{
+   this->type = glsl_type::error_type;
+}
+
+bool ir_rvalue::is_zero() const
+{
+   return false;
+}
+
+bool ir_rvalue::is_one() const
+{
+   return false;
+}
+
+bool ir_rvalue::is_negative_one() const
+{
+   return false;
+}
+
+/**
+ * Modify the swizzle make to move one component to another
+ *
+ * \param m    IR swizzle to be modified
+ * \param from Component in the RHS that is to be swizzled
+ * \param to   Desired swizzle location of \c from
+ */
+static void
+update_rhs_swizzle(ir_swizzle_mask &m, unsigned from, unsigned to)
+{
+   switch (to) {
+   case 0: m.x = from; break;
+   case 1: m.y = from; break;
+   case 2: m.z = from; break;
+   case 3: m.w = from; break;
+   default: assert(!"Should not get here.");
+   }
+}
+
+void
+ir_assignment::set_lhs(ir_rvalue *lhs)
+{
+   void *mem_ctx = this;
+   bool swizzled = false;
+
+   while (lhs != NULL) {
+      ir_swizzle *swiz = lhs->as_swizzle();
+
+      if (swiz == NULL)
+	 break;
+
+      unsigned write_mask = 0;
+      ir_swizzle_mask rhs_swiz = { 0, 0, 0, 0, 0, 0 };
+
+      for (unsigned i = 0; i < swiz->mask.num_components; i++) {
+	 unsigned c = 0;
+
+	 switch (i) {
+	 case 0: c = swiz->mask.x; break;
+	 case 1: c = swiz->mask.y; break;
+	 case 2: c = swiz->mask.z; break;
+	 case 3: c = swiz->mask.w; break;
+	 default: assert(!"Should not get here.");
+	 }
+
+	 write_mask |= (((this->write_mask >> i) & 1) << c);
+	 update_rhs_swizzle(rhs_swiz, i, c);
+         rhs_swiz.num_components = swiz->val->type->vector_elements;
+      }
+
+      this->write_mask = write_mask;
+      lhs = swiz->val;
+
+      this->rhs = new(mem_ctx) ir_swizzle(this->rhs, rhs_swiz);
+      swizzled = true;
+   }
+
+   if (swizzled) {
+      /* Now, RHS channels line up with the LHS writemask.  Collapse it
+       * to just the channels that will be written.
+       */
+      ir_swizzle_mask rhs_swiz = { 0, 0, 0, 0, 0, 0 };
+      int rhs_chan = 0;
+      for (int i = 0; i < 4; i++) {
+	 if (write_mask & (1 << i))
+	    update_rhs_swizzle(rhs_swiz, i, rhs_chan++);
+      }
+      rhs_swiz.num_components = rhs_chan;
+      this->rhs = new(mem_ctx) ir_swizzle(this->rhs, rhs_swiz);
+   }
+
+   assert((lhs == NULL) || lhs->as_dereference());
+
+   this->lhs = (ir_dereference *) lhs;
+}
+
+ir_variable *
+ir_assignment::whole_variable_written()
+{
+   ir_variable *v = this->lhs->whole_variable_referenced();
+
+   if (v == NULL)
+      return NULL;
+
+   if (v->type->is_scalar())
+      return v;
+
+   if (v->type->is_vector()) {
+      const unsigned mask = (1U << v->type->vector_elements) - 1;
+
+      if (mask != this->write_mask)
+	 return NULL;
+   }
+
+   /* Either all the vector components are assigned or the variable is some
+    * composite type (and the whole thing is assigned.
+    */
+   return v;
+}
+
+ir_assignment::ir_assignment(ir_dereference *lhs, ir_rvalue *rhs,
+			     ir_rvalue *condition, unsigned write_mask)
+   : ir_instruction(ir_type_assignment)
+{
+   this->condition = condition;
+   this->rhs = rhs;
+   this->lhs = lhs;
+   this->write_mask = write_mask;
+
+   if (lhs->type->is_scalar() || lhs->type->is_vector()) {
+      int lhs_components = 0;
+      for (int i = 0; i < 4; i++) {
+	 if (write_mask & (1 << i))
+	    lhs_components++;
+      }
+
+      assert(lhs_components == this->rhs->type->vector_elements);
+   }
+}
+
+ir_assignment::ir_assignment(ir_rvalue *lhs, ir_rvalue *rhs,
+			     ir_rvalue *condition)
+   : ir_instruction(ir_type_assignment)
+{
+   this->condition = condition;
+   this->rhs = rhs;
+
+   /* If the RHS is a vector type, assume that all components of the vector
+    * type are being written to the LHS.  The write mask comes from the RHS
+    * because we can have a case where the LHS is a vec4 and the RHS is a
+    * vec3.  In that case, the assignment is:
+    *
+    *     (assign (...) (xyz) (var_ref lhs) (var_ref rhs))
+    */
+   if (rhs->type->is_vector())
+      this->write_mask = (1U << rhs->type->vector_elements) - 1;
+   else if (rhs->type->is_scalar())
+      this->write_mask = 1;
+   else
+      this->write_mask = 0;
+
+   this->set_lhs(lhs);
+}
+
+ir_expression::ir_expression(int op, const struct glsl_type *type,
+			     ir_rvalue *op0, ir_rvalue *op1,
+			     ir_rvalue *op2, ir_rvalue *op3)
+   : ir_rvalue(ir_type_expression)
+{
+   this->type = type;
+   this->operation = ir_expression_operation(op);
+   this->operands[0] = op0;
+   this->operands[1] = op1;
+   this->operands[2] = op2;
+   this->operands[3] = op3;
+#ifndef NDEBUG
+   int num_operands = get_num_operands(this->operation);
+   for (int i = num_operands; i < 4; i++) {
+      assert(this->operands[i] == NULL);
+   }
+#endif
+}
+
+ir_expression::ir_expression(int op, ir_rvalue *op0)
+   : ir_rvalue(ir_type_expression)
+{
+   this->operation = ir_expression_operation(op);
+   this->operands[0] = op0;
+   this->operands[1] = NULL;
+   this->operands[2] = NULL;
+   this->operands[3] = NULL;
+
+   assert(op <= ir_last_unop);
+
+   switch (this->operation) {
+   case ir_unop_bit_not:
+   case ir_unop_logic_not:
+   case ir_unop_neg:
+   case ir_unop_abs:
+   case ir_unop_sign:
+   case ir_unop_rcp:
+   case ir_unop_rsq:
+   case ir_unop_sqrt:
+   case ir_unop_exp:
+   case ir_unop_log:
+   case ir_unop_exp2:
+   case ir_unop_log2:
+   case ir_unop_trunc:
+   case ir_unop_ceil:
+   case ir_unop_floor:
+   case ir_unop_fract:
+   case ir_unop_round_even:
+   case ir_unop_sin:
+   case ir_unop_cos:
+   case ir_unop_dFdx:
+   case ir_unop_dFdx_coarse:
+   case ir_unop_dFdx_fine:
+   case ir_unop_dFdy:
+   case ir_unop_dFdy_coarse:
+   case ir_unop_dFdy_fine:
+   case ir_unop_bitfield_reverse:
+   case ir_unop_interpolate_at_centroid:
+   case ir_unop_saturate:
+      this->type = op0->type;
+      break;
+
+   case ir_unop_f2i:
+   case ir_unop_b2i:
+   case ir_unop_u2i:
+   case ir_unop_d2i:
+   case ir_unop_bitcast_f2i:
+   case ir_unop_bit_count:
+   case ir_unop_find_msb:
+   case ir_unop_find_lsb:
+   case ir_unop_subroutine_to_int:
+      this->type = glsl_type::get_instance(GLSL_TYPE_INT,
+					   op0->type->vector_elements, 1);
+      break;
+
+   case ir_unop_b2f:
+   case ir_unop_i2f:
+   case ir_unop_u2f:
+   case ir_unop_d2f:
+   case ir_unop_bitcast_i2f:
+   case ir_unop_bitcast_u2f:
+      this->type = glsl_type::get_instance(GLSL_TYPE_FLOAT,
+					   op0->type->vector_elements, 1);
+      break;
+
+   case ir_unop_f2b:
+   case ir_unop_i2b:
+   case ir_unop_d2b:
+      this->type = glsl_type::get_instance(GLSL_TYPE_BOOL,
+					   op0->type->vector_elements, 1);
+      break;
+
+   case ir_unop_f2d:
+   case ir_unop_i2d:
+   case ir_unop_u2d:
+      this->type = glsl_type::get_instance(GLSL_TYPE_DOUBLE,
+					   op0->type->vector_elements, 1);
+      break;
+
+   case ir_unop_i2u:
+   case ir_unop_f2u:
+   case ir_unop_d2u:
+   case ir_unop_bitcast_f2u:
+      this->type = glsl_type::get_instance(GLSL_TYPE_UINT,
+					   op0->type->vector_elements, 1);
+      break;
+
+   case ir_unop_noise:
+   case ir_unop_unpack_half_2x16_split_x:
+   case ir_unop_unpack_half_2x16_split_y:
+      this->type = glsl_type::float_type;
+      break;
+
+   case ir_unop_unpack_double_2x32:
+      this->type = glsl_type::uvec2_type;
+      break;
+
+   case ir_unop_pack_snorm_2x16:
+   case ir_unop_pack_snorm_4x8:
+   case ir_unop_pack_unorm_2x16:
+   case ir_unop_pack_unorm_4x8:
+   case ir_unop_pack_half_2x16:
+      this->type = glsl_type::uint_type;
+      break;
+
+   case ir_unop_pack_double_2x32:
+      this->type = glsl_type::double_type;
+      break;
+
+   case ir_unop_unpack_snorm_2x16:
+   case ir_unop_unpack_unorm_2x16:
+   case ir_unop_unpack_half_2x16:
+      this->type = glsl_type::vec2_type;
+      break;
+
+   case ir_unop_unpack_snorm_4x8:
+   case ir_unop_unpack_unorm_4x8:
+      this->type = glsl_type::vec4_type;
+      break;
+
+   case ir_unop_frexp_sig:
+      this->type = op0->type;
+      break;
+   case ir_unop_frexp_exp:
+      this->type = glsl_type::get_instance(GLSL_TYPE_INT,
+					   op0->type->vector_elements, 1);
+      break;
+
+   case ir_unop_get_buffer_size:
+   case ir_unop_ssbo_unsized_array_length:
+      this->type = glsl_type::int_type;
+      break;
+
+   default:
+      assert(!"not reached: missing automatic type setup for ir_expression");
+      this->type = op0->type;
+      break;
+   }
+}
+
+ir_expression::ir_expression(int op, ir_rvalue *op0, ir_rvalue *op1)
+   : ir_rvalue(ir_type_expression)
+{
+   this->operation = ir_expression_operation(op);
+   this->operands[0] = op0;
+   this->operands[1] = op1;
+   this->operands[2] = NULL;
+   this->operands[3] = NULL;
+
+   assert(op > ir_last_unop);
+
+   switch (this->operation) {
+   case ir_binop_all_equal:
+   case ir_binop_any_nequal:
+      this->type = glsl_type::bool_type;
+      break;
+
+   case ir_binop_add:
+   case ir_binop_sub:
+   case ir_binop_min:
+   case ir_binop_max:
+   case ir_binop_pow:
+   case ir_binop_mul:
+   case ir_binop_div:
+   case ir_binop_mod:
+      if (op0->type->is_scalar()) {
+	 this->type = op1->type;
+      } else if (op1->type->is_scalar()) {
+	 this->type = op0->type;
+      } else {
+         if (this->operation == ir_binop_mul) {
+            this->type = glsl_type::get_mul_type(op0->type, op1->type);
+         } else {
+            assert(op0->type == op1->type);
+            this->type = op0->type;
+         }
+      }
+      break;
+
+   case ir_binop_logic_and:
+   case ir_binop_logic_xor:
+   case ir_binop_logic_or:
+   case ir_binop_bit_and:
+   case ir_binop_bit_xor:
+   case ir_binop_bit_or:
+       assert(!op0->type->is_matrix());
+       assert(!op1->type->is_matrix());
+      if (op0->type->is_scalar()) {
+         this->type = op1->type;
+      } else if (op1->type->is_scalar()) {
+         this->type = op0->type;
+      } else {
+          assert(op0->type->vector_elements == op1->type->vector_elements);
+          this->type = op0->type;
+      }
+      break;
+
+   case ir_binop_equal:
+   case ir_binop_nequal:
+   case ir_binop_lequal:
+   case ir_binop_gequal:
+   case ir_binop_less:
+   case ir_binop_greater:
+      assert(op0->type == op1->type);
+      this->type = glsl_type::get_instance(GLSL_TYPE_BOOL,
+					   op0->type->vector_elements, 1);
+      break;
+
+   case ir_binop_dot:
+      this->type = op0->type->get_base_type();
+      break;
+
+   case ir_binop_pack_half_2x16_split:
+      this->type = glsl_type::uint_type;
+      break;
+
+   case ir_binop_imul_high:
+   case ir_binop_carry:
+   case ir_binop_borrow:
+   case ir_binop_lshift:
+   case ir_binop_rshift:
+   case ir_binop_ldexp:
+   case ir_binop_interpolate_at_offset:
+   case ir_binop_interpolate_at_sample:
+      this->type = op0->type;
+      break;
+
+   case ir_binop_vector_extract:
+      this->type = op0->type->get_scalar_type();
+      break;
+
+   default:
+      assert(!"not reached: missing automatic type setup for ir_expression");
+      this->type = glsl_type::float_type;
+   }
+}
+
+ir_expression::ir_expression(int op, ir_rvalue *op0, ir_rvalue *op1,
+                             ir_rvalue *op2)
+   : ir_rvalue(ir_type_expression)
+{
+   this->operation = ir_expression_operation(op);
+   this->operands[0] = op0;
+   this->operands[1] = op1;
+   this->operands[2] = op2;
+   this->operands[3] = NULL;
+
+   assert(op > ir_last_binop && op <= ir_last_triop);
+
+   switch (this->operation) {
+   case ir_triop_fma:
+   case ir_triop_lrp:
+   case ir_triop_bitfield_extract:
+   case ir_triop_vector_insert:
+      this->type = op0->type;
+      break;
+
+   case ir_triop_csel:
+      this->type = op1->type;
+      break;
+
+   default:
+      assert(!"not reached: missing automatic type setup for ir_expression");
+      this->type = glsl_type::float_type;
+   }
+}
+
+unsigned int
+ir_expression::get_num_operands(ir_expression_operation op)
+{
+   assert(op <= ir_last_opcode);
+
+   if (op <= ir_last_unop)
+      return 1;
+
+   if (op <= ir_last_binop)
+      return 2;
+
+   if (op <= ir_last_triop)
+      return 3;
+
+   if (op <= ir_last_quadop)
+      return 4;
+
+   assert(false);
+   return 0;
+}
+
+static const char *const operator_strs[] = {
+   "~",
+   "!",
+   "neg",
+   "abs",
+   "sign",
+   "rcp",
+   "rsq",
+   "sqrt",
+   "exp",
+   "log",
+   "exp2",
+   "log2",
+   "f2i",
+   "f2u",
+   "i2f",
+   "f2b",
+   "b2f",
+   "i2b",
+   "b2i",
+   "u2f",
+   "i2u",
+   "u2i",
+   "d2f",
+   "f2d",
+   "d2i",
+   "i2d",
+   "d2u",
+   "u2d",
+   "d2b",
+   "bitcast_i2f",
+   "bitcast_f2i",
+   "bitcast_u2f",
+   "bitcast_f2u",
+   "trunc",
+   "ceil",
+   "floor",
+   "fract",
+   "round_even",
+   "sin",
+   "cos",
+   "dFdx",
+   "dFdxCoarse",
+   "dFdxFine",
+   "dFdy",
+   "dFdyCoarse",
+   "dFdyFine",
+   "packSnorm2x16",
+   "packSnorm4x8",
+   "packUnorm2x16",
+   "packUnorm4x8",
+   "packHalf2x16",
+   "unpackSnorm2x16",
+   "unpackSnorm4x8",
+   "unpackUnorm2x16",
+   "unpackUnorm4x8",
+   "unpackHalf2x16",
+   "unpackHalf2x16_split_x",
+   "unpackHalf2x16_split_y",
+   "bitfield_reverse",
+   "bit_count",
+   "find_msb",
+   "find_lsb",
+   "sat",
+   "packDouble2x32",
+   "unpackDouble2x32",
+   "frexp_sig",
+   "frexp_exp",
+   "noise",
+   "subroutine_to_int",
+   "interpolate_at_centroid",
+   "get_buffer_size",
+   "ssbo_unsized_array_length",
+   "+",
+   "-",
+   "*",
+   "imul_high",
+   "/",
+   "carry",
+   "borrow",
+   "%",
+   "<",
+   ">",
+   "<=",
+   ">=",
+   "==",
+   "!=",
+   "all_equal",
+   "any_nequal",
+   "<<",
+   ">>",
+   "&",
+   "^",
+   "|",
+   "&&",
+   "^^",
+   "||",
+   "dot",
+   "min",
+   "max",
+   "pow",
+   "packHalf2x16_split",
+   "ubo_load",
+   "ldexp",
+   "vector_extract",
+   "interpolate_at_offset",
+   "interpolate_at_sample",
+   "fma",
+   "lrp",
+   "csel",
+   "bitfield_extract",
+   "vector_insert",
+   "bitfield_insert",
+   "vector",
+};
+
+const char *ir_expression::operator_string(ir_expression_operation op)
+{
+   assert((unsigned int) op < ARRAY_SIZE(operator_strs));
+   assert(ARRAY_SIZE(operator_strs) == (ir_quadop_vector + 1));
+   return operator_strs[op];
+}
+
+const char *ir_expression::operator_string()
+{
+   return operator_string(this->operation);
+}
+
+const char*
+depth_layout_string(ir_depth_layout layout)
+{
+   switch(layout) {
+   case ir_depth_layout_none:      return "";
+   case ir_depth_layout_any:       return "depth_any";
+   case ir_depth_layout_greater:   return "depth_greater";
+   case ir_depth_layout_less:      return "depth_less";
+   case ir_depth_layout_unchanged: return "depth_unchanged";
+
+   default:
+      assert(0);
+      return "";
+   }
+}
+
+ir_expression_operation
+ir_expression::get_operator(const char *str)
+{
+   const int operator_count = sizeof(operator_strs) / sizeof(operator_strs[0]);
+   for (int op = 0; op < operator_count; op++) {
+      if (strcmp(str, operator_strs[op]) == 0)
+	 return (ir_expression_operation) op;
+   }
+   return (ir_expression_operation) -1;
+}
+
+ir_variable *
+ir_expression::variable_referenced() const
+{
+   switch (operation) {
+      case ir_binop_vector_extract:
+      case ir_triop_vector_insert:
+         /* We get these for things like a[0] where a is a vector type. In these
+          * cases we want variable_referenced() to return the actual vector
+          * variable this is wrapping.
+          */
+         return operands[0]->variable_referenced();
+      default:
+         return ir_rvalue::variable_referenced();
+   }
+}
+
+ir_constant::ir_constant()
+   : ir_rvalue(ir_type_constant)
+{
+}
+
+ir_constant::ir_constant(const struct glsl_type *type,
+			 const ir_constant_data *data)
+   : ir_rvalue(ir_type_constant)
+{
+   assert((type->base_type >= GLSL_TYPE_UINT)
+	  && (type->base_type <= GLSL_TYPE_BOOL));
+
+   this->type = type;
+   memcpy(& this->value, data, sizeof(this->value));
+}
+
+ir_constant::ir_constant(float f, unsigned vector_elements)
+   : ir_rvalue(ir_type_constant)
+{
+   assert(vector_elements <= 4);
+   this->type = glsl_type::get_instance(GLSL_TYPE_FLOAT, vector_elements, 1);
+   for (unsigned i = 0; i < vector_elements; i++) {
+      this->value.f[i] = f;
+   }
+   for (unsigned i = vector_elements; i < 16; i++)  {
+      this->value.f[i] = 0;
+   }
+}
+
+ir_constant::ir_constant(double d, unsigned vector_elements)
+   : ir_rvalue(ir_type_constant)
+{
+   assert(vector_elements <= 4);
+   this->type = glsl_type::get_instance(GLSL_TYPE_DOUBLE, vector_elements, 1);
+   for (unsigned i = 0; i < vector_elements; i++) {
+      this->value.d[i] = d;
+   }
+   for (unsigned i = vector_elements; i < 16; i++)  {
+      this->value.d[i] = 0.0;
+   }
+}
+
+ir_constant::ir_constant(unsigned int u, unsigned vector_elements)
+   : ir_rvalue(ir_type_constant)
+{
+   assert(vector_elements <= 4);
+   this->type = glsl_type::get_instance(GLSL_TYPE_UINT, vector_elements, 1);
+   for (unsigned i = 0; i < vector_elements; i++) {
+      this->value.u[i] = u;
+   }
+   for (unsigned i = vector_elements; i < 16; i++) {
+      this->value.u[i] = 0;
+   }
+}
+
+ir_constant::ir_constant(int integer, unsigned vector_elements)
+   : ir_rvalue(ir_type_constant)
+{
+   assert(vector_elements <= 4);
+   this->type = glsl_type::get_instance(GLSL_TYPE_INT, vector_elements, 1);
+   for (unsigned i = 0; i < vector_elements; i++) {
+      this->value.i[i] = integer;
+   }
+   for (unsigned i = vector_elements; i < 16; i++) {
+      this->value.i[i] = 0;
+   }
+}
+
+ir_constant::ir_constant(bool b, unsigned vector_elements)
+   : ir_rvalue(ir_type_constant)
+{
+   assert(vector_elements <= 4);
+   this->type = glsl_type::get_instance(GLSL_TYPE_BOOL, vector_elements, 1);
+   for (unsigned i = 0; i < vector_elements; i++) {
+      this->value.b[i] = b;
+   }
+   for (unsigned i = vector_elements; i < 16; i++) {
+      this->value.b[i] = false;
+   }
+}
+
+ir_constant::ir_constant(const ir_constant *c, unsigned i)
+   : ir_rvalue(ir_type_constant)
+{
+   this->type = c->type->get_base_type();
+
+   switch (this->type->base_type) {
+   case GLSL_TYPE_UINT:  this->value.u[0] = c->value.u[i]; break;
+   case GLSL_TYPE_INT:   this->value.i[0] = c->value.i[i]; break;
+   case GLSL_TYPE_FLOAT: this->value.f[0] = c->value.f[i]; break;
+   case GLSL_TYPE_BOOL:  this->value.b[0] = c->value.b[i]; break;
+   case GLSL_TYPE_DOUBLE: this->value.d[0] = c->value.d[i]; break;
+   default:              assert(!"Should not get here."); break;
+   }
+}
+
+ir_constant::ir_constant(const struct glsl_type *type, exec_list *value_list)
+   : ir_rvalue(ir_type_constant)
+{
+   this->type = type;
+
+   assert(type->is_scalar() || type->is_vector() || type->is_matrix()
+	  || type->is_record() || type->is_array());
+
+   if (type->is_array()) {
+      this->array_elements = ralloc_array(this, ir_constant *, type->length);
+      unsigned i = 0;
+      foreach_in_list(ir_constant, value, value_list) {
+	 assert(value->as_constant() != NULL);
+
+	 this->array_elements[i++] = value;
+      }
+      return;
+   }
+
+   /* If the constant is a record, the types of each of the entries in
+    * value_list must be a 1-for-1 match with the structure components.  Each
+    * entry must also be a constant.  Just move the nodes from the value_list
+    * to the list in the ir_constant.
+    */
+   /* FINISHME: Should there be some type checking and / or assertions here? */
+   /* FINISHME: Should the new constant take ownership of the nodes from
+    * FINISHME: value_list, or should it make copies?
+    */
+   if (type->is_record()) {
+      value_list->move_nodes_to(& this->components);
+      return;
+   }
+
+   for (unsigned i = 0; i < 16; i++) {
+      this->value.u[i] = 0;
+   }
+
+   ir_constant *value = (ir_constant *) (value_list->head);
+
+   /* Constructors with exactly one scalar argument are special for vectors
+    * and matrices.  For vectors, the scalar value is replicated to fill all
+    * the components.  For matrices, the scalar fills the components of the
+    * diagonal while the rest is filled with 0.
+    */
+   if (value->type->is_scalar() && value->next->is_tail_sentinel()) {
+      if (type->is_matrix()) {
+	 /* Matrix - fill diagonal (rest is already set to 0) */
+         assert(type->base_type == GLSL_TYPE_FLOAT ||
+                type->base_type == GLSL_TYPE_DOUBLE);
+         for (unsigned i = 0; i < type->matrix_columns; i++) {
+            if (type->base_type == GLSL_TYPE_FLOAT)
+               this->value.f[i * type->vector_elements + i] =
+                  value->value.f[0];
+            else
+               this->value.d[i * type->vector_elements + i] =
+                  value->value.d[0];
+         }
+      } else {
+	 /* Vector or scalar - fill all components */
+	 switch (type->base_type) {
+	 case GLSL_TYPE_UINT:
+	 case GLSL_TYPE_INT:
+	    for (unsigned i = 0; i < type->components(); i++)
+	       this->value.u[i] = value->value.u[0];
+	    break;
+	 case GLSL_TYPE_FLOAT:
+	    for (unsigned i = 0; i < type->components(); i++)
+	       this->value.f[i] = value->value.f[0];
+	    break;
+	 case GLSL_TYPE_DOUBLE:
+	    for (unsigned i = 0; i < type->components(); i++)
+	       this->value.d[i] = value->value.d[0];
+	    break;
+	 case GLSL_TYPE_BOOL:
+	    for (unsigned i = 0; i < type->components(); i++)
+	       this->value.b[i] = value->value.b[0];
+	    break;
+	 default:
+	    assert(!"Should not get here.");
+	    break;
+	 }
+      }
+      return;
+   }
+
+   if (type->is_matrix() && value->type->is_matrix()) {
+      assert(value->next->is_tail_sentinel());
+
+      /* From section 5.4.2 of the GLSL 1.20 spec:
+       * "If a matrix is constructed from a matrix, then each component
+       *  (column i, row j) in the result that has a corresponding component
+       *  (column i, row j) in the argument will be initialized from there."
+       */
+      unsigned cols = MIN2(type->matrix_columns, value->type->matrix_columns);
+      unsigned rows = MIN2(type->vector_elements, value->type->vector_elements);
+      for (unsigned i = 0; i < cols; i++) {
+	 for (unsigned j = 0; j < rows; j++) {
+	    const unsigned src = i * value->type->vector_elements + j;
+	    const unsigned dst = i * type->vector_elements + j;
+	    this->value.f[dst] = value->value.f[src];
+	 }
+      }
+
+      /* "All other components will be initialized to the identity matrix." */
+      for (unsigned i = cols; i < type->matrix_columns; i++)
+	 this->value.f[i * type->vector_elements + i] = 1.0;
+
+      return;
+   }
+
+   /* Use each component from each entry in the value_list to initialize one
+    * component of the constant being constructed.
+    */
+   for (unsigned i = 0; i < type->components(); /* empty */) {
+      assert(value->as_constant() != NULL);
+      assert(!value->is_tail_sentinel());
+
+      for (unsigned j = 0; j < value->type->components(); j++) {
+	 switch (type->base_type) {
+	 case GLSL_TYPE_UINT:
+	    this->value.u[i] = value->get_uint_component(j);
+	    break;
+	 case GLSL_TYPE_INT:
+	    this->value.i[i] = value->get_int_component(j);
+	    break;
+	 case GLSL_TYPE_FLOAT:
+	    this->value.f[i] = value->get_float_component(j);
+	    break;
+	 case GLSL_TYPE_BOOL:
+	    this->value.b[i] = value->get_bool_component(j);
+	    break;
+	 case GLSL_TYPE_DOUBLE:
+	    this->value.d[i] = value->get_double_component(j);
+	    break;
+	 default:
+	    /* FINISHME: What to do?  Exceptions are not the answer.
+	     */
+	    break;
+	 }
+
+	 i++;
+	 if (i >= type->components())
+	    break;
+      }
+
+      value = (ir_constant *) value->next;
+   }
+}
+
+ir_constant *
+ir_constant::zero(void *mem_ctx, const glsl_type *type)
+{
+   assert(type->is_scalar() || type->is_vector() || type->is_matrix()
+	  || type->is_record() || type->is_array());
+
+   ir_constant *c = new(mem_ctx) ir_constant;
+   c->type = type;
+   memset(&c->value, 0, sizeof(c->value));
+
+   if (type->is_array()) {
+      c->array_elements = ralloc_array(c, ir_constant *, type->length);
+
+      for (unsigned i = 0; i < type->length; i++)
+	 c->array_elements[i] = ir_constant::zero(c, type->fields.array);
+   }
+
+   if (type->is_record()) {
+      for (unsigned i = 0; i < type->length; i++) {
+	 ir_constant *comp = ir_constant::zero(mem_ctx, type->fields.structure[i].type);
+	 c->components.push_tail(comp);
+      }
+   }
+
+   return c;
+}
+
+bool
+ir_constant::get_bool_component(unsigned i) const
+{
+   switch (this->type->base_type) {
+   case GLSL_TYPE_UINT:  return this->value.u[i] != 0;
+   case GLSL_TYPE_INT:   return this->value.i[i] != 0;
+   case GLSL_TYPE_FLOAT: return ((int)this->value.f[i]) != 0;
+   case GLSL_TYPE_BOOL:  return this->value.b[i];
+   case GLSL_TYPE_DOUBLE: return this->value.d[i] != 0.0;
+   default:              assert(!"Should not get here."); break;
+   }
+
+   /* Must return something to make the compiler happy.  This is clearly an
+    * error case.
+    */
+   return false;
+}
+
+float
+ir_constant::get_float_component(unsigned i) const
+{
+   switch (this->type->base_type) {
+   case GLSL_TYPE_UINT:  return (float) this->value.u[i];
+   case GLSL_TYPE_INT:   return (float) this->value.i[i];
+   case GLSL_TYPE_FLOAT: return this->value.f[i];
+   case GLSL_TYPE_BOOL:  return this->value.b[i] ? 1.0f : 0.0f;
+   case GLSL_TYPE_DOUBLE: return (float) this->value.d[i];
+   default:              assert(!"Should not get here."); break;
+   }
+
+   /* Must return something to make the compiler happy.  This is clearly an
+    * error case.
+    */
+   return 0.0;
+}
+
+double
+ir_constant::get_double_component(unsigned i) const
+{
+   switch (this->type->base_type) {
+   case GLSL_TYPE_UINT:  return (double) this->value.u[i];
+   case GLSL_TYPE_INT:   return (double) this->value.i[i];
+   case GLSL_TYPE_FLOAT: return (double) this->value.f[i];
+   case GLSL_TYPE_BOOL:  return this->value.b[i] ? 1.0 : 0.0;
+   case GLSL_TYPE_DOUBLE: return this->value.d[i];
+   default:              assert(!"Should not get here."); break;
+   }
+
+   /* Must return something to make the compiler happy.  This is clearly an
+    * error case.
+    */
+   return 0.0;
+}
+
+int
+ir_constant::get_int_component(unsigned i) const
+{
+   switch (this->type->base_type) {
+   case GLSL_TYPE_UINT:  return this->value.u[i];
+   case GLSL_TYPE_INT:   return this->value.i[i];
+   case GLSL_TYPE_FLOAT: return (int) this->value.f[i];
+   case GLSL_TYPE_BOOL:  return this->value.b[i] ? 1 : 0;
+   case GLSL_TYPE_DOUBLE: return (int) this->value.d[i];
+   default:              assert(!"Should not get here."); break;
+   }
+
+   /* Must return something to make the compiler happy.  This is clearly an
+    * error case.
+    */
+   return 0;
+}
+
+unsigned
+ir_constant::get_uint_component(unsigned i) const
+{
+   switch (this->type->base_type) {
+   case GLSL_TYPE_UINT:  return this->value.u[i];
+   case GLSL_TYPE_INT:   return this->value.i[i];
+   case GLSL_TYPE_FLOAT: return (unsigned) this->value.f[i];
+   case GLSL_TYPE_BOOL:  return this->value.b[i] ? 1 : 0;
+   case GLSL_TYPE_DOUBLE: return (unsigned) this->value.d[i];
+   default:              assert(!"Should not get here."); break;
+   }
+
+   /* Must return something to make the compiler happy.  This is clearly an
+    * error case.
+    */
+   return 0;
+}
+
+ir_constant *
+ir_constant::get_array_element(unsigned i) const
+{
+   assert(this->type->is_array());
+
+   /* From page 35 (page 41 of the PDF) of the GLSL 1.20 spec:
+    *
+    *     "Behavior is undefined if a shader subscripts an array with an index
+    *     less than 0 or greater than or equal to the size the array was
+    *     declared with."
+    *
+    * Most out-of-bounds accesses are removed before things could get this far.
+    * There are cases where non-constant array index values can get constant
+    * folded.
+    */
+   if (int(i) < 0)
+      i = 0;
+   else if (i >= this->type->length)
+      i = this->type->length - 1;
+
+   return array_elements[i];
+}
+
+ir_constant *
+ir_constant::get_record_field(const char *name)
+{
+   int idx = this->type->field_index(name);
+
+   if (idx < 0)
+      return NULL;
+
+   if (this->components.is_empty())
+      return NULL;
+
+   exec_node *node = this->components.head;
+   for (int i = 0; i < idx; i++) {
+      node = node->next;
+
+      /* If the end of the list is encountered before the element matching the
+       * requested field is found, return NULL.
+       */
+      if (node->is_tail_sentinel())
+	 return NULL;
+   }
+
+   return (ir_constant *) node;
+}
+
+void
+ir_constant::copy_offset(ir_constant *src, int offset)
+{
+   switch (this->type->base_type) {
+   case GLSL_TYPE_UINT:
+   case GLSL_TYPE_INT:
+   case GLSL_TYPE_FLOAT:
+   case GLSL_TYPE_DOUBLE:
+   case GLSL_TYPE_BOOL: {
+      unsigned int size = src->type->components();
+      assert (size <= this->type->components() - offset);
+      for (unsigned int i=0; i<size; i++) {
+	 switch (this->type->base_type) {
+	 case GLSL_TYPE_UINT:
+	    value.u[i+offset] = src->get_uint_component(i);
+	    break;
+	 case GLSL_TYPE_INT:
+	    value.i[i+offset] = src->get_int_component(i);
+	    break;
+	 case GLSL_TYPE_FLOAT:
+	    value.f[i+offset] = src->get_float_component(i);
+	    break;
+	 case GLSL_TYPE_BOOL:
+	    value.b[i+offset] = src->get_bool_component(i);
+	    break;
+	 case GLSL_TYPE_DOUBLE:
+	    value.d[i+offset] = src->get_double_component(i);
+	    break;
+	 default: // Shut up the compiler
+	    break;
+	 }
+      }
+      break;
+   }
+
+   case GLSL_TYPE_STRUCT: {
+      assert (src->type == this->type);
+      this->components.make_empty();
+      foreach_in_list(ir_constant, orig, &src->components) {
+	 this->components.push_tail(orig->clone(this, NULL));
+      }
+      break;
+   }
+
+   case GLSL_TYPE_ARRAY: {
+      assert (src->type == this->type);
+      for (unsigned i = 0; i < this->type->length; i++) {
+	 this->array_elements[i] = src->array_elements[i]->clone(this, NULL);
+      }
+      break;
+   }
+
+   default:
+      assert(!"Should not get here.");
+      break;
+   }
+}
+
+void
+ir_constant::copy_masked_offset(ir_constant *src, int offset, unsigned int mask)
+{
+   assert (!type->is_array() && !type->is_record());
+
+   if (!type->is_vector() && !type->is_matrix()) {
+      offset = 0;
+      mask = 1;
+   }
+
+   int id = 0;
+   for (int i=0; i<4; i++) {
+      if (mask & (1 << i)) {
+	 switch (this->type->base_type) {
+	 case GLSL_TYPE_UINT:
+	    value.u[i+offset] = src->get_uint_component(id++);
+	    break;
+	 case GLSL_TYPE_INT:
+	    value.i[i+offset] = src->get_int_component(id++);
+	    break;
+	 case GLSL_TYPE_FLOAT:
+	    value.f[i+offset] = src->get_float_component(id++);
+	    break;
+	 case GLSL_TYPE_BOOL:
+	    value.b[i+offset] = src->get_bool_component(id++);
+	    break;
+	 case GLSL_TYPE_DOUBLE:
+	    value.d[i+offset] = src->get_double_component(id++);
+	    break;
+	 default:
+	    assert(!"Should not get here.");
+	    return;
+	 }
+      }
+   }
+}
+
+bool
+ir_constant::has_value(const ir_constant *c) const
+{
+   if (this->type != c->type)
+      return false;
+
+   if (this->type->is_array()) {
+      for (unsigned i = 0; i < this->type->length; i++) {
+	 if (!this->array_elements[i]->has_value(c->array_elements[i]))
+	    return false;
+      }
+      return true;
+   }
+
+   if (this->type->base_type == GLSL_TYPE_STRUCT) {
+      const exec_node *a_node = this->components.head;
+      const exec_node *b_node = c->components.head;
+
+      while (!a_node->is_tail_sentinel()) {
+	 assert(!b_node->is_tail_sentinel());
+
+	 const ir_constant *const a_field = (ir_constant *) a_node;
+	 const ir_constant *const b_field = (ir_constant *) b_node;
+
+	 if (!a_field->has_value(b_field))
+	    return false;
+
+	 a_node = a_node->next;
+	 b_node = b_node->next;
+      }
+
+      return true;
+   }
+
+   for (unsigned i = 0; i < this->type->components(); i++) {
+      switch (this->type->base_type) {
+      case GLSL_TYPE_UINT:
+	 if (this->value.u[i] != c->value.u[i])
+	    return false;
+	 break;
+      case GLSL_TYPE_INT:
+	 if (this->value.i[i] != c->value.i[i])
+	    return false;
+	 break;
+      case GLSL_TYPE_FLOAT:
+	 if (this->value.f[i] != c->value.f[i])
+	    return false;
+	 break;
+      case GLSL_TYPE_BOOL:
+	 if (this->value.b[i] != c->value.b[i])
+	    return false;
+	 break;
+      case GLSL_TYPE_DOUBLE:
+	 if (this->value.d[i] != c->value.d[i])
+	    return false;
+	 break;
+      default:
+	 assert(!"Should not get here.");
+	 return false;
+      }
+   }
+
+   return true;
+}
+
+bool
+ir_constant::is_value(float f, int i) const
+{
+   if (!this->type->is_scalar() && !this->type->is_vector())
+      return false;
+
+   /* Only accept boolean values for 0/1. */
+   if (int(bool(i)) != i && this->type->is_boolean())
+      return false;
+
+   for (unsigned c = 0; c < this->type->vector_elements; c++) {
+      switch (this->type->base_type) {
+      case GLSL_TYPE_FLOAT:
+	 if (this->value.f[c] != f)
+	    return false;
+	 break;
+      case GLSL_TYPE_INT:
+	 if (this->value.i[c] != i)
+	    return false;
+	 break;
+      case GLSL_TYPE_UINT:
+	 if (this->value.u[c] != unsigned(i))
+	    return false;
+	 break;
+      case GLSL_TYPE_BOOL:
+	 if (this->value.b[c] != bool(i))
+	    return false;
+	 break;
+      case GLSL_TYPE_DOUBLE:
+	 if (this->value.d[c] != double(f))
+	    return false;
+	 break;
+      default:
+	 /* The only other base types are structures, arrays, and samplers.
+	  * Samplers cannot be constants, and the others should have been
+	  * filtered out above.
+	  */
+	 assert(!"Should not get here.");
+	 return false;
+      }
+   }
+
+   return true;
+}
+
+bool
+ir_constant::is_zero() const
+{
+   return is_value(0.0, 0);
+}
+
+bool
+ir_constant::is_one() const
+{
+   return is_value(1.0, 1);
+}
+
+bool
+ir_constant::is_negative_one() const
+{
+   return is_value(-1.0, -1);
+}
+
+bool
+ir_constant::is_uint16_constant() const
+{
+   if (!type->is_integer())
+      return false;
+
+   return value.u[0] < (1 << 16);
+}
+
+ir_loop::ir_loop()
+   : ir_instruction(ir_type_loop)
+{
+}
+
+
+ir_dereference_variable::ir_dereference_variable(ir_variable *var)
+   : ir_dereference(ir_type_dereference_variable)
+{
+   assert(var != NULL);
+
+   this->var = var;
+   this->type = var->type;
+}
+
+
+ir_dereference_array::ir_dereference_array(ir_rvalue *value,
+					   ir_rvalue *array_index)
+   : ir_dereference(ir_type_dereference_array)
+{
+   this->array_index = array_index;
+   this->set_array(value);
+}
+
+
+ir_dereference_array::ir_dereference_array(ir_variable *var,
+					   ir_rvalue *array_index)
+   : ir_dereference(ir_type_dereference_array)
+{
+   void *ctx = ralloc_parent(var);
+
+   this->array_index = array_index;
+   this->set_array(new(ctx) ir_dereference_variable(var));
+}
+
+
+void
+ir_dereference_array::set_array(ir_rvalue *value)
+{
+   assert(value != NULL);
+
+   this->array = value;
+
+   const glsl_type *const vt = this->array->type;
+
+   if (vt->is_array()) {
+      type = vt->fields.array;
+   } else if (vt->is_matrix()) {
+      type = vt->column_type();
+   } else if (vt->is_vector()) {
+      type = vt->get_base_type();
+   }
+}
+
+
+ir_dereference_record::ir_dereference_record(ir_rvalue *value,
+					     const char *field)
+   : ir_dereference(ir_type_dereference_record)
+{
+   assert(value != NULL);
+
+   this->record = value;
+   this->field = ralloc_strdup(this, field);
+   this->type = this->record->type->field_type(field);
+}
+
+
+ir_dereference_record::ir_dereference_record(ir_variable *var,
+					     const char *field)
+   : ir_dereference(ir_type_dereference_record)
+{
+   void *ctx = ralloc_parent(var);
+
+   this->record = new(ctx) ir_dereference_variable(var);
+   this->field = ralloc_strdup(this, field);
+   this->type = this->record->type->field_type(field);
+}
+
+bool
+ir_dereference::is_lvalue() const
+{
+   ir_variable *var = this->variable_referenced();
+
+   /* Every l-value derference chain eventually ends in a variable.
+    */
+   if ((var == NULL) || var->data.read_only)
+      return false;
+
+   /* From section 4.1.7 of the GLSL 4.40 spec:
+    *
+    *   "Opaque variables cannot be treated as l-values; hence cannot
+    *    be used as out or inout function parameters, nor can they be
+    *    assigned into."
+    */
+   if (this->type->contains_opaque())
+      return false;
+
+   return true;
+}
+
+
+static const char * const tex_opcode_strs[] = { "tex", "txb", "txl", "txd", "txf", "txf_ms", "txs", "lod", "tg4", "query_levels", "texture_samples", "samples_identical" };
+
+const char *ir_texture::opcode_string()
+{
+   assert((unsigned int) op < ARRAY_SIZE(tex_opcode_strs));
+   return tex_opcode_strs[op];
+}
+
+ir_texture_opcode
+ir_texture::get_opcode(const char *str)
+{
+   const int count = sizeof(tex_opcode_strs) / sizeof(tex_opcode_strs[0]);
+   for (int op = 0; op < count; op++) {
+      if (strcmp(str, tex_opcode_strs[op]) == 0)
+	 return (ir_texture_opcode) op;
+   }
+   return (ir_texture_opcode) -1;
+}
+
+
+void
+ir_texture::set_sampler(ir_dereference *sampler, const glsl_type *type)
+{
+   assert(sampler != NULL);
+   assert(type != NULL);
+   this->sampler = sampler;
+   this->type = type;
+
+   if (this->op == ir_txs || this->op == ir_query_levels ||
+       this->op == ir_texture_samples) {
+      assert(type->base_type == GLSL_TYPE_INT);
+   } else if (this->op == ir_lod) {
+      assert(type->vector_elements == 2);
+      assert(type->base_type == GLSL_TYPE_FLOAT);
+   } else if (this->op == ir_samples_identical) {
+      assert(type == glsl_type::bool_type);
+      assert(sampler->type->base_type == GLSL_TYPE_SAMPLER);
+      assert(sampler->type->sampler_dimensionality == GLSL_SAMPLER_DIM_MS);
+   } else {
+      assert(sampler->type->sampler_type == (int) type->base_type);
+      if (sampler->type->sampler_shadow)
+	 assert(type->vector_elements == 4 || type->vector_elements == 1);
+      else
+	 assert(type->vector_elements == 4);
+   }
+}
+
+
+void
+ir_swizzle::init_mask(const unsigned *comp, unsigned count)
+{
+   assert((count >= 1) && (count <= 4));
+
+   memset(&this->mask, 0, sizeof(this->mask));
+   this->mask.num_components = count;
+
+   unsigned dup_mask = 0;
+   switch (count) {
+   case 4:
+      assert(comp[3] <= 3);
+      dup_mask |= (1U << comp[3])
+	 & ((1U << comp[0]) | (1U << comp[1]) | (1U << comp[2]));
+      this->mask.w = comp[3];
+
+   case 3:
+      assert(comp[2] <= 3);
+      dup_mask |= (1U << comp[2])
+	 & ((1U << comp[0]) | (1U << comp[1]));
+      this->mask.z = comp[2];
+
+   case 2:
+      assert(comp[1] <= 3);
+      dup_mask |= (1U << comp[1])
+	 & ((1U << comp[0]));
+      this->mask.y = comp[1];
+
+   case 1:
+      assert(comp[0] <= 3);
+      this->mask.x = comp[0];
+   }
+
+   this->mask.has_duplicates = dup_mask != 0;
+
+   /* Based on the number of elements in the swizzle and the base type
+    * (i.e., float, int, unsigned, or bool) of the vector being swizzled,
+    * generate the type of the resulting value.
+    */
+   type = glsl_type::get_instance(val->type->base_type, mask.num_components, 1);
+}
+
+ir_swizzle::ir_swizzle(ir_rvalue *val, unsigned x, unsigned y, unsigned z,
+		       unsigned w, unsigned count)
+   : ir_rvalue(ir_type_swizzle), val(val)
+{
+   const unsigned components[4] = { x, y, z, w };
+   this->init_mask(components, count);
+}
+
+ir_swizzle::ir_swizzle(ir_rvalue *val, const unsigned *comp,
+		       unsigned count)
+   : ir_rvalue(ir_type_swizzle), val(val)
+{
+   this->init_mask(comp, count);
+}
+
+ir_swizzle::ir_swizzle(ir_rvalue *val, ir_swizzle_mask mask)
+   : ir_rvalue(ir_type_swizzle)
+{
+   this->val = val;
+   this->mask = mask;
+   this->type = glsl_type::get_instance(val->type->base_type,
+					mask.num_components, 1);
+}
+
+#define X 1
+#define R 5
+#define S 9
+#define I 13
+
+ir_swizzle *
+ir_swizzle::create(ir_rvalue *val, const char *str, unsigned vector_length)
+{
+   void *ctx = ralloc_parent(val);
+
+   /* For each possible swizzle character, this table encodes the value in
+    * \c idx_map that represents the 0th element of the vector.  For invalid
+    * swizzle characters (e.g., 'k'), a special value is used that will allow
+    * detection of errors.
+    */
+   static const unsigned char base_idx[26] = {
+   /* a  b  c  d  e  f  g  h  i  j  k  l  m */
+      R, R, I, I, I, I, R, I, I, I, I, I, I,
+   /* n  o  p  q  r  s  t  u  v  w  x  y  z */
+      I, I, S, S, R, S, S, I, I, X, X, X, X
+   };
+
+   /* Each valid swizzle character has an entry in the previous table.  This
+    * table encodes the base index encoded in the previous table plus the actual
+    * index of the swizzle character.  When processing swizzles, the first
+    * character in the string is indexed in the previous table.  Each character
+    * in the string is indexed in this table, and the value found there has the
+    * value form the first table subtracted.  The result must be on the range
+    * [0,3].
+    *
+    * For example, the string "wzyx" will get X from the first table.  Each of
+    * the charcaters will get X+3, X+2, X+1, and X+0 from this table.  After
+    * subtraction, the swizzle values are { 3, 2, 1, 0 }.
+    *
+    * The string "wzrg" will get X from the first table.  Each of the characters
+    * will get X+3, X+2, R+0, and R+1 from this table.  After subtraction, the
+    * swizzle values are { 3, 2, 4, 5 }.  Since 4 and 5 are outside the range
+    * [0,3], the error is detected.
+    */
+   static const unsigned char idx_map[26] = {
+   /* a    b    c    d    e    f    g    h    i    j    k    l    m */
+      R+3, R+2, 0,   0,   0,   0,   R+1, 0,   0,   0,   0,   0,   0,
+   /* n    o    p    q    r    s    t    u    v    w    x    y    z */
+      0,   0,   S+2, S+3, R+0, S+0, S+1, 0,   0,   X+3, X+0, X+1, X+2
+   };
+
+   int swiz_idx[4] = { 0, 0, 0, 0 };
+   unsigned i;
+
+
+   /* Validate the first character in the swizzle string and look up the base
+    * index value as described above.
+    */
+   if ((str[0] < 'a') || (str[0] > 'z'))
+      return NULL;
+
+   const unsigned base = base_idx[str[0] - 'a'];
+
+
+   for (i = 0; (i < 4) && (str[i] != '\0'); i++) {
+      /* Validate the next character, and, as described above, convert it to a
+       * swizzle index.
+       */
+      if ((str[i] < 'a') || (str[i] > 'z'))
+	 return NULL;
+
+      swiz_idx[i] = idx_map[str[i] - 'a'] - base;
+      if ((swiz_idx[i] < 0) || (swiz_idx[i] >= (int) vector_length))
+	 return NULL;
+   }
+
+   if (str[i] != '\0')
+	 return NULL;
+
+   return new(ctx) ir_swizzle(val, swiz_idx[0], swiz_idx[1], swiz_idx[2],
+			      swiz_idx[3], i);
+}
+
+#undef X
+#undef R
+#undef S
+#undef I
+
+ir_variable *
+ir_swizzle::variable_referenced() const
+{
+   return this->val->variable_referenced();
+}
+
+
+bool ir_variable::temporaries_allocate_names = false;
+
+const char ir_variable::tmp_name[] = "compiler_temp";
+
+ir_variable::ir_variable(const struct glsl_type *type, const char *name,
+			 ir_variable_mode mode)
+   : ir_instruction(ir_type_variable)
+{
+   this->type = type;
+
+   if (mode == ir_var_temporary && !ir_variable::temporaries_allocate_names)
+      name = NULL;
+
+   /* The ir_variable clone method may call this constructor with name set to
+    * tmp_name.
+    */
+   assert(name != NULL
+          || mode == ir_var_temporary
+          || mode == ir_var_function_in
+          || mode == ir_var_function_out
+          || mode == ir_var_function_inout);
+   assert(name != ir_variable::tmp_name
+          || mode == ir_var_temporary);
+   if (mode == ir_var_temporary
+       && (name == NULL || name == ir_variable::tmp_name)) {
+      this->name = ir_variable::tmp_name;
+   } else {
+      this->name = ralloc_strdup(this, name);
+   }
+
+   this->u.max_ifc_array_access = NULL;
+
+   this->data.explicit_location = false;
+   this->data.has_initializer = false;
+   this->data.location = -1;
+   this->data.location_frac = 0;
+   this->data.binding = 0;
+   this->data.warn_extension_index = 0;
+   this->constant_value = NULL;
+   this->constant_initializer = NULL;
+   this->data.origin_upper_left = false;
+   this->data.pixel_center_integer = false;
+   this->data.depth_layout = ir_depth_layout_none;
+   this->data.used = false;
+   this->data.always_active_io = false;
+   this->data.read_only = false;
+   this->data.centroid = false;
+   this->data.sample = false;
+   this->data.patch = false;
+   this->data.invariant = false;
+   this->data.how_declared = ir_var_declared_normally;
+   this->data.mode = mode;
+   this->data.interpolation = INTERP_QUALIFIER_NONE;
+   this->data.max_array_access = 0;
+   this->data.offset = 0;
+   this->data.precision = GLSL_PRECISION_NONE;
+   this->data.image_read_only = false;
+   this->data.image_write_only = false;
+   this->data.image_coherent = false;
+   this->data.image_volatile = false;
+   this->data.image_restrict = false;
+   this->data.from_ssbo_unsized_array = false;
+
+   if (type != NULL) {
+      if (type->base_type == GLSL_TYPE_SAMPLER)
+         this->data.read_only = true;
+
+      if (type->is_interface())
+         this->init_interface_type(type);
+      else if (type->without_array()->is_interface())
+         this->init_interface_type(type->without_array());
+   }
+}
+
+
+const char *
+interpolation_string(unsigned interpolation)
+{
+   switch (interpolation) {
+   case INTERP_QUALIFIER_NONE:          return "no";
+   case INTERP_QUALIFIER_SMOOTH:        return "smooth";
+   case INTERP_QUALIFIER_FLAT:          return "flat";
+   case INTERP_QUALIFIER_NOPERSPECTIVE: return "noperspective";
+   }
+
+   assert(!"Should not get here.");
+   return "";
+}
+
+
+glsl_interp_qualifier
+ir_variable::determine_interpolation_mode(bool flat_shade)
+{
+   if (this->data.interpolation != INTERP_QUALIFIER_NONE)
+      return (glsl_interp_qualifier) this->data.interpolation;
+   int location = this->data.location;
+   bool is_gl_Color =
+      location == VARYING_SLOT_COL0 || location == VARYING_SLOT_COL1;
+   if (flat_shade && is_gl_Color)
+      return INTERP_QUALIFIER_FLAT;
+   else
+      return INTERP_QUALIFIER_SMOOTH;
+}
+
+const char *const ir_variable::warn_extension_table[] = {
+   "",
+   "GL_ARB_shader_stencil_export",
+   "GL_AMD_shader_stencil_export",
+};
+
+void
+ir_variable::enable_extension_warning(const char *extension)
+{
+   for (unsigned i = 0; i < ARRAY_SIZE(warn_extension_table); i++) {
+      if (strcmp(warn_extension_table[i], extension) == 0) {
+         this->data.warn_extension_index = i;
+         return;
+      }
+   }
+
+   assert(!"Should not get here.");
+   this->data.warn_extension_index = 0;
+}
+
+const char *
+ir_variable::get_extension_warning() const
+{
+   return this->data.warn_extension_index == 0
+      ? NULL : warn_extension_table[this->data.warn_extension_index];
+}
+
+ir_function_signature::ir_function_signature(const glsl_type *return_type,
+                                             builtin_available_predicate b)
+   : ir_instruction(ir_type_function_signature),
+     return_type(return_type), is_defined(false), is_intrinsic(false),
+     builtin_avail(b), _function(NULL)
+{
+   this->origin = NULL;
+}
+
+
+bool
+ir_function_signature::is_builtin() const
+{
+   return builtin_avail != NULL;
+}
+
+
+bool
+ir_function_signature::is_builtin_available(const _mesa_glsl_parse_state *state) const
+{
+   /* We can't call the predicate without a state pointer, so just say that
+    * the signature is available.  At compile time, we need the filtering,
+    * but also receive a valid state pointer.  At link time, we're resolving
+    * imported built-in prototypes to their definitions, which will always
+    * be an exact match.  So we can skip the filtering.
+    */
+   if (state == NULL)
+      return true;
+
+   assert(builtin_avail != NULL);
+   return builtin_avail(state);
+}
+
+
+static bool
+modes_match(unsigned a, unsigned b)
+{
+   if (a == b)
+      return true;
+
+   /* Accept "in" vs. "const in" */
+   if ((a == ir_var_const_in && b == ir_var_function_in) ||
+       (b == ir_var_const_in && a == ir_var_function_in))
+      return true;
+
+   return false;
+}
+
+
+const char *
+ir_function_signature::qualifiers_match(exec_list *params)
+{
+   /* check that the qualifiers match. */
+   foreach_two_lists(a_node, &this->parameters, b_node, params) {
+      ir_variable *a = (ir_variable *) a_node;
+      ir_variable *b = (ir_variable *) b_node;
+
+      if (a->data.read_only != b->data.read_only ||
+	  !modes_match(a->data.mode, b->data.mode) ||
+	  a->data.interpolation != b->data.interpolation ||
+	  a->data.centroid != b->data.centroid ||
+          a->data.sample != b->data.sample ||
+          a->data.patch != b->data.patch ||
+          a->data.image_read_only != b->data.image_read_only ||
+          a->data.image_write_only != b->data.image_write_only ||
+          a->data.image_coherent != b->data.image_coherent ||
+          a->data.image_volatile != b->data.image_volatile ||
+          a->data.image_restrict != b->data.image_restrict) {
+
+	 /* parameter a's qualifiers don't match */
+	 return a->name;
+      }
+   }
+   return NULL;
+}
+
+
+void
+ir_function_signature::replace_parameters(exec_list *new_params)
+{
+   /* Destroy all of the previous parameter information.  If the previous
+    * parameter information comes from the function prototype, it may either
+    * specify incorrect parameter names or not have names at all.
+    */
+   new_params->move_nodes_to(&parameters);
+}
+
+
+ir_function::ir_function(const char *name)
+   : ir_instruction(ir_type_function)
+{
+   this->subroutine_index = -1;
+   this->name = ralloc_strdup(this, name);
+}
+
+
+bool
+ir_function::has_user_signature()
+{
+   foreach_in_list(ir_function_signature, sig, &this->signatures) {
+      if (!sig->is_builtin())
+	 return true;
+   }
+   return false;
+}
+
+
+ir_rvalue *
+ir_rvalue::error_value(void *mem_ctx)
+{
+   ir_rvalue *v = new(mem_ctx) ir_rvalue(ir_type_unset);
+
+   v->type = glsl_type::error_type;
+   return v;
+}
+
+
+void
+visit_exec_list(exec_list *list, ir_visitor *visitor)
+{
+   foreach_in_list_safe(ir_instruction, node, list) {
+      node->accept(visitor);
+   }
+}
+
+
+static void
+steal_memory(ir_instruction *ir, void *new_ctx)
+{
+   ir_variable *var = ir->as_variable();
+   ir_function *fn = ir->as_function();
+   ir_constant *constant = ir->as_constant();
+   if (var != NULL && var->constant_value != NULL)
+      steal_memory(var->constant_value, ir);
+
+   if (var != NULL && var->constant_initializer != NULL)
+      steal_memory(var->constant_initializer, ir);
+
+   if (fn != NULL && fn->subroutine_types)
+      ralloc_steal(new_ctx, fn->subroutine_types);
+
+   /* The components of aggregate constants are not visited by the normal
+    * visitor, so steal their values by hand.
+    */
+   if (constant != NULL) {
+      if (constant->type->is_record()) {
+	 foreach_in_list(ir_constant, field, &constant->components) {
+	    steal_memory(field, ir);
+	 }
+      } else if (constant->type->is_array()) {
+	 for (unsigned int i = 0; i < constant->type->length; i++) {
+	    steal_memory(constant->array_elements[i], ir);
+	 }
+      }
+   }
+
+   ralloc_steal(new_ctx, ir);
+}
+
+
+void
+reparent_ir(exec_list *list, void *mem_ctx)
+{
+   foreach_in_list(ir_instruction, node, list) {
+      visit_tree(node, steal_memory, mem_ctx);
+   }
+}
+
+
+static ir_rvalue *
+try_min_one(ir_rvalue *ir)
+{
+   ir_expression *expr = ir->as_expression();
+
+   if (!expr || expr->operation != ir_binop_min)
+      return NULL;
+
+   if (expr->operands[0]->is_one())
+      return expr->operands[1];
+
+   if (expr->operands[1]->is_one())
+      return expr->operands[0];
+
+   return NULL;
+}
+
+static ir_rvalue *
+try_max_zero(ir_rvalue *ir)
+{
+   ir_expression *expr = ir->as_expression();
+
+   if (!expr || expr->operation != ir_binop_max)
+      return NULL;
+
+   if (expr->operands[0]->is_zero())
+      return expr->operands[1];
+
+   if (expr->operands[1]->is_zero())
+      return expr->operands[0];
+
+   return NULL;
+}
+
+ir_rvalue *
+ir_rvalue::as_rvalue_to_saturate()
+{
+   ir_expression *expr = this->as_expression();
+
+   if (!expr)
+      return NULL;
+
+   ir_rvalue *max_zero = try_max_zero(expr);
+   if (max_zero) {
+      return try_min_one(max_zero);
+   } else {
+      ir_rvalue *min_one = try_min_one(expr);
+      if (min_one) {
+	 return try_max_zero(min_one);
+      }
+   }
+
+   return NULL;
+}
+
+
+unsigned
+vertices_per_prim(GLenum prim)
+{
+   switch (prim) {
+   case GL_POINTS:
+      return 1;
+   case GL_LINES:
+      return 2;
+   case GL_TRIANGLES:
+      return 3;
+   case GL_LINES_ADJACENCY:
+      return 4;
+   case GL_TRIANGLES_ADJACENCY:
+      return 6;
+   default:
+      assert(!"Bad primitive");
+      return 3;
+   }
+}
+
+/**
+ * Generate a string describing the mode of a variable
+ */
+const char *
+mode_string(const ir_variable *var)
+{
+   switch (var->data.mode) {
+   case ir_var_auto:
+      return (var->data.read_only) ? "global constant" : "global variable";
+
+   case ir_var_uniform:
+      return "uniform";
+
+   case ir_var_shader_storage:
+      return "buffer";
+
+   case ir_var_shader_in:
+      return "shader input";
+
+   case ir_var_shader_out:
+      return "shader output";
+
+   case ir_var_function_in:
+   case ir_var_const_in:
+      return "function input";
+
+   case ir_var_function_out:
+      return "function output";
+
+   case ir_var_function_inout:
+      return "function inout";
+
+   case ir_var_system_value:
+      return "shader input";
+
+   case ir_var_temporary:
+      return "compiler temporary";
+
+   case ir_var_mode_count:
+      break;
+   }
+
+   assert(!"Should not get here.");
+   return "invalid variable";
+}