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

1 files changed, 256 insertions, 0 deletions

diff --git a/src/glsl/ir_copy_propagation.cpp b/src/glsl/ir_copy_propagation.cpp
new file mode 100644
index 00000000000..46ef6679d9f
--- /dev/null
+++ b/src/glsl/ir_copy_propagation.cpp
@@ -0,0 +1,256 @@
+/*
+ * 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 ir_copy_propagation.cpp
+ *
+ * Moves usage of recently-copied variables to the previous copy of
+ * the variable within basic blocks.
+ *
+ * This should reduce the number of MOV instructions in the generated
+ * programs unless copy propagation is also done on the LIR, and may
+ * help anyway by triggering other optimizations that live in the HIR.
+ */
+
+#include "ir.h"
+#include "ir_visitor.h"
+#include "ir_basic_block.h"
+#include "ir_optimization.h"
+#include "glsl_types.h"
+
+class acp_entry : public exec_node
+{
+public:
+   acp_entry(ir_variable *lhs, ir_variable *rhs)
+   {
+      assert(lhs);
+      assert(rhs);
+      this->lhs = lhs;
+      this->rhs = rhs;
+   }
+
+   ir_variable *lhs;
+   ir_variable *rhs;
+};
+
+class ir_copy_propagation_visitor : public ir_hierarchical_visitor {
+public:
+   ir_copy_propagation_visitor(exec_list *acp)
+   {
+      progress = false;
+      in_lhs = false;
+      this->acp = acp;
+   }
+
+   virtual ir_visitor_status visit(class ir_dereference_variable *);
+   virtual ir_visitor_status visit_enter(class ir_loop *);
+   virtual ir_visitor_status visit_enter(class ir_function_signature *);
+   virtual ir_visitor_status visit_enter(class ir_function *);
+   virtual ir_visitor_status visit_enter(class ir_assignment *);
+   virtual ir_visitor_status visit_enter(class ir_call *);
+   virtual ir_visitor_status visit_enter(class ir_if *);
+
+   /** List of acp_entry */
+   exec_list *acp;
+   bool progress;
+
+   /** Currently in the LHS of an assignment? */
+   bool in_lhs;
+};
+
+
+ir_visitor_status
+ir_copy_propagation_visitor::visit_enter(ir_loop *ir)
+{
+   (void)ir;
+   return visit_continue_with_parent;
+}
+
+ir_visitor_status
+ir_copy_propagation_visitor::visit_enter(ir_function_signature *ir)
+{
+   (void)ir;
+   return visit_continue_with_parent;
+}
+
+ir_visitor_status
+ir_copy_propagation_visitor::visit_enter(ir_assignment *ir)
+{
+   (void) ir;
+   this->in_lhs = true;
+   return visit_continue;
+}
+
+ir_visitor_status
+ir_copy_propagation_visitor::visit_enter(ir_function *ir)
+{
+   (void) ir;
+   return visit_continue_with_parent;
+}
+
+/**
+ * Replaces dereferences of ACP RHS variables with ACP LHS variables.
+ *
+ * This is where the actual copy propagation occurs.  Note that the
+ * rewriting of ir_dereference means that the ir_dereference instance
+ * must not be shared by multiple IR operations!
+ */
+ir_visitor_status
+ir_copy_propagation_visitor::visit(ir_dereference_variable *ir)
+{
+   /* Ignores the LHS.  Don't want to rewrite the LHS to point at some
+    * other storage!
+    */
+   if (this->in_lhs) {
+      this->in_lhs = false;
+      return visit_continue;
+   }
+
+   ir_variable *var = ir->variable_referenced();
+
+   foreach_iter(exec_list_iterator, iter, *this->acp) {
+      acp_entry *entry = (acp_entry *)iter.get();
+
+      if (var == entry->lhs) {
+	 ir->var = entry->rhs;
+	 this->progress = true;
+	 break;
+      }
+   }
+
+   return visit_continue;
+}
+
+
+ir_visitor_status
+ir_copy_propagation_visitor::visit_enter(ir_call *ir)
+{
+   (void)ir;
+
+   /* Note, if we were to do copy propagation to parameters of calls, we'd
+    * have to be careful about out params.
+    */
+   return visit_continue_with_parent;
+}
+
+
+ir_visitor_status
+ir_copy_propagation_visitor::visit_enter(ir_if *ir)
+{
+   ir->condition->accept(this);
+
+   /* Do not traverse into the body of the if-statement since that is a
+    * different basic block.
+    */
+   return visit_continue_with_parent;
+}
+
+static bool
+propagate_copies(ir_instruction *ir, exec_list *acp)
+{
+   ir_copy_propagation_visitor v(acp);
+
+   ir->accept(&v);
+
+   return v.progress;
+}
+
+static void
+kill_invalidated_copies(ir_assignment *ir, exec_list *acp)
+{
+   ir_variable *var = ir->lhs->variable_referenced();
+   assert(var != NULL);
+
+   foreach_iter(exec_list_iterator, iter, *acp) {
+      acp_entry *entry = (acp_entry *)iter.get();
+
+      if (entry->lhs == var || entry->rhs == var) {
+	 entry->remove();
+      }
+   }
+}
+
+/**
+ * Adds an entry to the available copy list if it's a plain assignment
+ * of a variable to a variable.
+ */
+static void
+add_copy(ir_assignment *ir, exec_list *acp)
+{
+   void *ctx = talloc_parent(ir);
+   acp_entry *entry;
+
+   if (ir->condition) {
+      ir_constant *condition = ir->condition->as_constant();
+      if (!condition || !condition->value.b[0])
+	 return;
+   }
+
+   ir_variable *lhs_var = ir->lhs->whole_variable_referenced();
+   ir_variable *rhs_var = ir->rhs->whole_variable_referenced();
+
+   if ((lhs_var != NULL) && (rhs_var != NULL)) {
+      entry = new(ctx) acp_entry(lhs_var, rhs_var);
+      acp->push_tail(entry);
+   }
+}
+
+static void
+copy_propagation_basic_block(ir_instruction *first,
+			     ir_instruction *last,
+			     void *data)
+{
+   ir_instruction *ir;
+   /* List of avaialble_copy */
+   exec_list acp;
+   bool *out_progress = (bool *)data;
+   bool progress = false;
+
+   for (ir = first;; ir = (ir_instruction *)ir->next) {
+      ir_assignment *ir_assign = ir->as_assignment();
+
+      progress = propagate_copies(ir, &acp) || progress;
+
+      if (ir_assign) {
+	 kill_invalidated_copies(ir_assign, &acp);
+
+	 add_copy(ir_assign, &acp);
+      }
+      if (ir == last)
+	 break;
+   }
+   *out_progress = progress;
+}
+
+/**
+ * Does a copy propagation pass on the code present in the instruction stream.
+ */
+bool
+do_copy_propagation(exec_list *instructions)
+{
+   bool progress = false;
+
+   call_for_basic_blocks(instructions, copy_propagation_basic_block, &progress);
+
+   return progress;
+}