xserver and mesa git update 28-12-2010

1 files changed, 425 insertions, 0 deletions

diff --git a/mesalib/src/mesa/program/register_allocate.c b/mesalib/src/mesa/program/register_allocate.c
new file mode 100644
index 000000000..93e0cbe78
--- /dev/null
+++ b/mesalib/src/mesa/program/register_allocate.c
@@ -0,0 +1,425 @@
+/*

+ * 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.

+ *

+ * Authors:

+ *    Eric Anholt <eric@anholt.net>

+ *

+ */

+

+/** @file register_allocate.c

+ *

+ * Graph-coloring register allocator.

+ */

+

+#include <talloc.h>

+

+#include "main/imports.h"

+#include "main/macros.h"

+#include "main/mtypes.h"

+#include "register_allocate.h"

+

+struct ra_reg {

+   char *name;

+   GLboolean *conflicts;

+};

+

+struct ra_regs {

+   struct ra_reg *regs;

+   unsigned int count;

+

+   struct ra_class **classes;

+   unsigned int class_count;

+};

+

+struct ra_class {

+   GLboolean *regs;

+

+   /**

+    * p_B in Runeson/Nyström paper.

+    *

+    * This is "how many regs are in the set."

+    */

+   unsigned int p;

+

+   /**

+    * q_B,C in Runeson/Nyström paper.

+    */

+   unsigned int *q;

+};

+

+struct ra_node {

+   GLboolean *adjacency;

+   unsigned int class;

+   unsigned int adjacency_count;

+   unsigned int reg;

+   GLboolean in_stack;

+   float spill_cost;

+};

+

+struct ra_graph {

+   struct ra_regs *regs;

+   /**

+    * the variables that need register allocation.

+    */

+   struct ra_node *nodes;

+   unsigned int count; /**< count of nodes. */

+

+   unsigned int *stack;

+   unsigned int stack_count;

+};

+

+struct ra_regs *

+ra_alloc_reg_set(unsigned int count)

+{

+   unsigned int i;

+   struct ra_regs *regs;

+

+   regs = talloc_zero(NULL, struct ra_regs);

+   regs->count = count;

+   regs->regs = talloc_zero_array(regs, struct ra_reg, count);

+

+   for (i = 0; i < count; i++) {

+      regs->regs[i].conflicts = talloc_zero_array(regs->regs, GLboolean, count);

+      regs->regs[i].conflicts[i] = GL_TRUE;

+   }

+

+   return regs;

+}

+

+void

+ra_add_reg_conflict(struct ra_regs *regs, unsigned int r1, unsigned int r2)

+{

+   regs->regs[r1].conflicts[r2] = GL_TRUE;

+   regs->regs[r2].conflicts[r1] = GL_TRUE;

+}

+

+unsigned int

+ra_alloc_reg_class(struct ra_regs *regs)

+{

+   struct ra_class *class;

+

+   regs->classes = talloc_realloc(regs, regs->classes,

+				  struct ra_class *,

+				  regs->class_count + 1);

+

+   class = talloc_zero(regs, struct ra_class);

+   regs->classes[regs->class_count] = class;

+

+   class->regs = talloc_zero_array(class, GLboolean, regs->count);

+

+   return regs->class_count++;

+}

+

+void

+ra_class_add_reg(struct ra_regs *regs, unsigned int c, unsigned int r)

+{

+   struct ra_class *class = regs->classes[c];

+

+   class->regs[r] = GL_TRUE;

+   class->p++;

+}

+

+/**

+ * Must be called after all conflicts and register classes have been

+ * set up and before the register set is used for allocation.

+ */

+void

+ra_set_finalize(struct ra_regs *regs)

+{

+   unsigned int b, c;

+

+   for (b = 0; b < regs->class_count; b++) {

+      regs->classes[b]->q = talloc_array(regs, unsigned int, regs->class_count);

+   }

+

+   /* Compute, for each class B and C, how many regs of B an

+    * allocation to C could conflict with.

+    */

+   for (b = 0; b < regs->class_count; b++) {

+      for (c = 0; c < regs->class_count; c++) {

+	 unsigned int rc;

+	 int max_conflicts = 0;

+

+	 for (rc = 0; rc < regs->count; rc++) {

+	    unsigned int rb;

+	    int conflicts = 0;

+

+	    if (!regs->classes[c]->regs[rc])

+	       continue;

+

+	    for (rb = 0; rb < regs->count; rb++) {

+	       if (regs->classes[b]->regs[rb] &&

+		   regs->regs[rb].conflicts[rc])

+		  conflicts++;

+	    }

+	    max_conflicts = MAX2(max_conflicts, conflicts);

+	 }

+	 regs->classes[b]->q[c] = max_conflicts;

+      }

+   }

+}

+

+struct ra_graph *

+ra_alloc_interference_graph(struct ra_regs *regs, unsigned int count)

+{

+   struct ra_graph *g;

+   unsigned int i;

+

+   g = talloc_zero(regs, struct ra_graph);

+   g->regs = regs;

+   g->nodes = talloc_zero_array(g, struct ra_node, count);

+   g->count = count;

+

+   g->stack = talloc_zero_array(g, unsigned int, count);

+

+   for (i = 0; i < count; i++) {

+      g->nodes[i].adjacency = talloc_zero_array(g, GLboolean, count);

+      g->nodes[i].adjacency[i] = GL_TRUE;

+      g->nodes[i].reg = ~0;

+   }

+

+   return g;

+}

+

+void

+ra_set_node_class(struct ra_graph *g,

+		  unsigned int n, unsigned int class)

+{

+   g->nodes[n].class = class;

+}

+

+void

+ra_add_node_interference(struct ra_graph *g,

+			 unsigned int n1, unsigned int n2)

+{

+   if (g->nodes[n1].adjacency[n2])

+      return;

+

+   g->nodes[n1].adjacency[n2] = GL_TRUE;

+   g->nodes[n2].adjacency_count++;

+   g->nodes[n2].adjacency[n1] = GL_TRUE;

+   g->nodes[n2].adjacency_count++;

+}

+

+static GLboolean pq_test(struct ra_graph *g, unsigned int n)

+{

+   unsigned int j;

+   unsigned int q = 0;

+   int n_class = g->nodes[n].class;

+

+   for (j = 0; j < g->count; j++) {

+      if (j == n || g->nodes[j].in_stack)

+	 continue;

+

+      if (g->nodes[n].adjacency[j]) {

+	 unsigned int j_class = g->nodes[j].class;

+	 q += g->regs->classes[n_class]->q[j_class];

+      }

+   }

+

+   return q < g->regs->classes[n_class]->p;

+}

+

+/**

+ * Simplifies the interference graph by pushing all

+ * trivially-colorable nodes into a stack of nodes to be colored,

+ * removing them from the graph, and rinsing and repeating.

+ *

+ * Returns GL_TRUE if all nodes were removed from the graph.  GL_FALSE

+ * means that either spilling will be required, or optimistic coloring

+ * should be applied.

+ */

+GLboolean

+ra_simplify(struct ra_graph *g)

+{

+   GLboolean progress = GL_TRUE;

+   int i;

+

+   while (progress) {

+      progress = GL_FALSE;

+

+      for (i = g->count - 1; i >= 0; i--) {

+	 if (g->nodes[i].in_stack)

+	    continue;

+

+	 if (pq_test(g, i)) {

+	    g->stack[g->stack_count] = i;

+	    g->stack_count++;

+	    g->nodes[i].in_stack = GL_TRUE;

+	    progress = GL_TRUE;

+	 }

+      }

+   }

+

+   for (i = 0; i < g->count; i++) {

+      if (!g->nodes[i].in_stack)

+	 return GL_FALSE;

+   }

+

+   return GL_TRUE;

+}

+

+/**

+ * Pops nodes from the stack back into the graph, coloring them with

+ * registers as they go.

+ *

+ * If all nodes were trivially colorable, then this must succeed.  If

+ * not (optimistic coloring), then it may return GL_FALSE;

+ */

+GLboolean

+ra_select(struct ra_graph *g)

+{

+   int i;

+

+   while (g->stack_count != 0) {

+      unsigned int r;

+      int n = g->stack[g->stack_count - 1];

+      struct ra_class *c = g->regs->classes[g->nodes[n].class];

+

+      /* Find the lowest-numbered reg which is not used by a member

+       * of the graph adjacent to us.

+       */

+      for (r = 0; r < g->regs->count; r++) {

+	 if (!c->regs[r])

+	    continue;

+

+	 /* Check if any of our neighbors conflict with this register choice. */

+	 for (i = 0; i < g->count; i++) {

+	    if (g->nodes[n].adjacency[i] &&

+	       !g->nodes[i].in_stack &&

+		g->regs->regs[r].conflicts[g->nodes[i].reg]) {

+	       break;

+	    }

+	 }

+	 if (i == g->count)

+	    break;

+      }

+      if (r == g->regs->count)

+	 return GL_FALSE;

+

+      g->nodes[n].reg = r;

+      g->nodes[n].in_stack = GL_FALSE;

+      g->stack_count--;

+   }

+

+   return GL_TRUE;

+}

+

+/**

+ * Optimistic register coloring: Just push the remaining nodes

+ * on the stack.  They'll be colored first in ra_select(), and

+ * if they succeed then the locally-colorable nodes are still

+ * locally-colorable and the rest of the register allocation

+ * will succeed.

+ */

+void

+ra_optimistic_color(struct ra_graph *g)

+{

+   unsigned int i;

+

+   for (i = 0; i < g->count; i++) {

+      if (g->nodes[i].in_stack)

+	 continue;

+

+      g->stack[g->stack_count] = i;

+      g->stack_count++;

+      g->nodes[i].in_stack = GL_TRUE;

+   }

+}

+

+GLboolean

+ra_allocate_no_spills(struct ra_graph *g)

+{

+   if (!ra_simplify(g)) {

+      ra_optimistic_color(g);

+   }

+   return ra_select(g);

+}

+

+unsigned int

+ra_get_node_reg(struct ra_graph *g, unsigned int n)

+{

+   return g->nodes[n].reg;

+}

+

+static float

+ra_get_spill_benefit(struct ra_graph *g, unsigned int n)

+{

+   int j;

+   float benefit = 0;

+   int n_class = g->nodes[n].class;

+

+   /* Define the benefit of eliminating an interference between n, j

+    * through spilling as q(C, B) / p(C).  This is similar to the

+    * "count number of edges" approach of traditional graph coloring,

+    * but takes classes into account.

+    */

+   for (j = 0; j < g->count; j++) {

+      if (j != n && g->nodes[n].adjacency[j]) {

+	 unsigned int j_class = g->nodes[j].class;

+	 benefit += ((float)g->regs->classes[n_class]->q[j_class] /

+		     g->regs->classes[n_class]->p);

+	 break;

+      }

+   }

+

+   return benefit;

+}

+

+/**

+ * Returns a node number to be spilled according to the cost/benefit using

+ * the pq test, or -1 if there are no spillable nodes.

+ */

+int

+ra_get_best_spill_node(struct ra_graph *g)

+{

+   unsigned int best_node = -1;

+   unsigned int best_benefit = 0.0;

+   unsigned int n;

+

+   for (n = 0; n < g->count; n++) {

+      float cost = g->nodes[n].spill_cost;

+      float benefit;

+

+      if (cost <= 0.0)

+	 continue;

+

+      benefit = ra_get_spill_benefit(g, n);

+

+      if (benefit / cost > best_benefit) {

+	 best_benefit = benefit / cost;

+	 best_node = n;

+      }

+   }

+

+   return best_node;

+}

+

+/**

+ * Only nodes with a spill cost set (cost != 0.0) will be considered

+ * for register spilling.

+ */

+void

+ra_set_node_spill_cost(struct ra_graph *g, unsigned int n, float cost)

+{

+   g->nodes[n].spill_cost = cost;

+}