xserver and mesa git update 28-12-2010

1 files changed, 224 insertions, 0 deletions

diff --git a/mesalib/src/glsl/lower_vector.cpp b/mesalib/src/glsl/lower_vector.cpp
new file mode 100644
index 000000000..3ed8d05d6
--- /dev/null
+++ b/mesalib/src/glsl/lower_vector.cpp
@@ -0,0 +1,224 @@
+/*

+ * 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.

+ */

+

+/**

+ * \file lower_vector.cpp

+ * IR lowering pass to remove some types of ir_quadop_vector

+ *

+ * \author Ian Romanick <ian.d.romanick@intel.com>

+ */

+

+#include "ir.h"

+#include "ir_rvalue_visitor.h"

+

+class lower_vector_visitor : public ir_rvalue_visitor {

+public:

+   lower_vector_visitor() : progress(false)

+   {

+      /* empty */

+   }

+

+   void handle_rvalue(ir_rvalue **rvalue);

+

+   /**

+    * Should SWZ-like expressions be lowered?

+    */

+   bool dont_lower_swz;

+

+   bool progress;

+};

+

+/**

+ * Determine if an IR expression tree looks like an extended swizzle

+ *

+ * Extended swizzles consist of access of a single vector source (with possible

+ * per component negation) and the constants -1, 0, or 1.

+ */

+bool

+is_extended_swizzle(ir_expression *ir)

+{

+   /* Track any variables that are accessed by this expression.

+    */

+   ir_variable *var = NULL;

+

+   assert(ir->operation == ir_quadop_vector);

+

+   for (unsigned i = 0; i < ir->type->vector_elements; i++) {

+      ir_rvalue *op = ir->operands[i];

+

+      while (op != NULL) {

+	 switch (op->ir_type) {

+	 case ir_type_constant: {

+	    const ir_constant *const c = op->as_constant();

+

+	    if (!c->is_one() && !c->is_zero() && !c->is_negative_one())

+	       return false;

+

+	    op = NULL;

+	    break;

+	 }

+

+	 case ir_type_dereference_variable: {

+	    ir_dereference_variable *const d = (ir_dereference_variable *) op;

+

+	    if ((var != NULL) && (var != d->var))

+	       return false;

+

+	    var = d->var;

+	    op = NULL;

+	    break;

+	 }

+

+	 case ir_type_expression: {

+	    ir_expression *const ex = (ir_expression *) op;

+

+	    if (ex->operation != ir_unop_neg)

+	       return false;

+

+	    op = ex->operands[0];

+	    break;

+	 }

+

+	 case ir_type_swizzle:

+	    op = ((ir_swizzle *) op)->val;

+	    break;

+

+	 default:

+	    return false;

+	 }

+      }

+   }

+

+   return true;

+}

+

+void

+lower_vector_visitor::handle_rvalue(ir_rvalue **rvalue)

+{

+   if (!*rvalue)

+      return;

+

+   ir_expression *expr = (*rvalue)->as_expression();

+   if ((expr == NULL) || (expr->operation != ir_quadop_vector))

+      return;

+

+   if (this->dont_lower_swz && is_extended_swizzle(expr))

+      return;

+

+   /* FINISHME: Is this the right thing to use for the talloc context?

+    */

+   void *const mem_ctx = expr;

+

+   assert(expr->type->vector_elements == expr->get_num_operands());

+

+   /* Generate a temporary with the same type as the ir_quadop_operation.

+    */

+   ir_variable *const temp =

+      new(mem_ctx) ir_variable(expr->type, "vecop_tmp", ir_var_temporary);

+

+   this->base_ir->insert_before(temp);

+

+   /* Counter of the number of components collected so far.

+    */

+   unsigned assigned;

+

+   /* Write-mask in the destination that receives counted by 'assigned'.

+    */

+   unsigned write_mask;

+

+

+   /* Generate upto four assignments to that variable.  Try to group component

+    * assignments together:

+    *

+    * - All constant components can be assigned at once.

+    * - All assigments of components from a single variable with the same

+    *   unary operator can be assigned at once.

+    */

+   ir_constant_data d = { { 0 } };

+

+   assigned = 0;

+   write_mask = 0;

+   for (unsigned i = 0; i < expr->type->vector_elements; i++) {

+      const ir_constant *const c = expr->operands[i]->as_constant();

+

+      if (c == NULL)

+	 continue;

+

+      switch (expr->type->base_type) {

+      case GLSL_TYPE_UINT:  d.u[assigned] = c->value.u[0]; break;

+      case GLSL_TYPE_INT:   d.i[assigned] = c->value.i[0]; break;

+      case GLSL_TYPE_FLOAT: d.f[assigned] = c->value.f[0]; break;

+      case GLSL_TYPE_BOOL:  d.b[assigned] = c->value.b[0]; break;

+      default:              assert(!"Should not get here."); break;

+      }

+

+      write_mask |= (1U << i);

+      assigned++;

+   }

+

+   assert((write_mask == 0) == (assigned == 0));

+

+   /* If there were constant values, generate an assignment.

+    */

+   if (assigned > 0) {

+      ir_constant *const c =

+	 new(mem_ctx) ir_constant(glsl_type::get_instance(expr->type->base_type,

+							  assigned, 0),

+				  &d);

+      ir_dereference *const lhs = new(mem_ctx) ir_dereference_variable(temp);

+      ir_assignment *const assign =

+	 new(mem_ctx) ir_assignment(lhs, c, NULL, write_mask);

+

+      this->base_ir->insert_before(assign);

+   }

+

+   /* FINISHME: This should try to coalesce assignments.

+    */

+   for (unsigned i = 0; i < expr->type->vector_elements; i++) {

+      if (expr->operands[i]->ir_type == ir_type_constant)

+	 continue;

+

+      ir_dereference *const lhs = new(mem_ctx) ir_dereference_variable(temp);

+      ir_assignment *const assign =

+	 new(mem_ctx) ir_assignment(lhs, expr->operands[i], NULL, (1U << i));

+

+      this->base_ir->insert_before(assign);

+      assigned++;

+   }

+

+   assert(assigned == expr->type->vector_elements);

+

+   *rvalue = new(mem_ctx) ir_dereference_variable(temp);

+   this->progress = true;

+}

+

+bool

+lower_quadop_vector(exec_list *instructions, bool dont_lower_swz)

+{

+   lower_vector_visitor v;

+

+   v.dont_lower_swz = dont_lower_swz;

+   visit_list_elements(&v, instructions);

+

+   return v.progress;

+}