libxtrans fontconfig glproto libX11 libxcb xcbproto mesa xserver pixman xkeyboard-config git update 22 Dec 2013

xserver          commit a68df147421da21528b5be2d34678383922fa352
libxcb           commit f653464554469b5767f1c99abced25a76bace047
libxcb/xcb-proto commit 4087fc682c5ceb849b74442e17a6b73176e5eecb
xkeyboard-config commit a224a636139d22e1dc7ca7d23782cd656e87bcf5
libX11           commit 3d69b0a83e62f8f6fbdd952fc49cdbdf8825e1e6
libXdmcp         commit 089081dca4ba3598c6f9bf401c029378943b5854
libXext          commit bb24f2970f2e425f4df90c9b73d078ad15a73fbb
libfontenc       commit 3acba630d8b57084f7e92c15732408711ed5137a
libXinerama      commit edd95182b26eb5d576d4878c559e0f17dddaa909
libXau           commit 304a11be4727c5a7feeb2501e8e001466f8ce84e
xkbcomp          commit e3e6e938535532bfad175c1635256ab7fb3ac943
pixman           commit 945ab7a6f3eb6241f07e8f094dc0e647d1f10d9d
xextproto        commit 3f355f138d6df57e067458a20f47307883048adb
randrproto       commit e7526e6b5fe0966929cda10b2ded0258413744db
glproto          commit f84853d97d5749308992412a215fa518b6536eb3
mkfontscale      commit 880a0c4733e62e54e6a0f1238c7430727d23657b
xwininfo         commit ba0d1b0da21d2dbdd81098ed5778f3792b472e13
libXft           commit 4acfdaf95adb0a05c2a25550bdde036c865902f4
libXmu           commit 22d9c590901e121936f50dee97dc60c4f7defb63
libxtrans        commit 2c0a7840a28ae696e80e73157856d7a049fdf6c7
fontconfig       commit 5c725f2f5829238d16116f782d00d8bb0defaf08
mesa             commit 2efe7927d38983029784825fc4897e9b77aa237e

1 files changed, 157 insertions, 39 deletions

diff --git a/mesalib/src/glsl/loop_analysis.cpp b/mesalib/src/glsl/loop_analysis.cpp
index b08241af5..fd2b6c923 100644
--- a/mesalib/src/glsl/loop_analysis.cpp
+++ b/mesalib/src/glsl/loop_analysis.cpp
@@ -33,6 +33,46 @@ static bool all_expression_operands_are_loop_constant(ir_rvalue *,
 static ir_rvalue *get_basic_induction_increment(ir_assignment *, hash_table *);
 
 
+/**
+ * Record the fact that the given loop variable was referenced inside the loop.
+ *
+ * \arg in_assignee is true if the reference was on the LHS of an assignment.
+ *
+ * \arg in_conditional_code_or_nested_loop is true if the reference occurred
+ * inside an if statement or a nested loop.
+ *
+ * \arg current_assignment is the ir_assignment node that the loop variable is
+ * on the LHS of, if any (ignored if \c in_assignee is false).
+ */
+void
+loop_variable::record_reference(bool in_assignee,
+                                bool in_conditional_code_or_nested_loop,
+                                ir_assignment *current_assignment)
+{
+   if (in_assignee) {
+      assert(current_assignment != NULL);
+
+      if (in_conditional_code_or_nested_loop ||
+          current_assignment->condition != NULL) {
+         this->conditional_or_nested_assignment = true;
+      }
+
+      if (this->first_assignment == NULL) {
+         assert(this->num_assignments == 0);
+
+         this->first_assignment = current_assignment;
+      }
+
+      this->num_assignments++;
+   } else if (this->first_assignment == current_assignment) {
+      /* This catches the case where the variable is used in the RHS of an
+       * assignment where it is also in the LHS.
+       */
+      this->read_before_write = true;
+   }
+}
+
+
 loop_state::loop_state()
 {
    this->ht = hash_table_ctor(0, hash_table_pointer_hash,
@@ -94,7 +134,7 @@ loop_terminator *
 loop_variable_state::insert(ir_if *if_stmt)
 {
    void *mem_ctx = ralloc_parent(this);
-   loop_terminator *t = rzalloc(mem_ctx, loop_terminator);
+   loop_terminator *t = new(mem_ctx) loop_terminator();
 
    t->ir = if_stmt;
    this->terminators.push_tail(t);
@@ -102,6 +142,33 @@ loop_variable_state::insert(ir_if *if_stmt)
    return t;
 }
 
+
+/**
+ * If the given variable already is recorded in the state for this loop,
+ * return the corresponding loop_variable object that records information
+ * about it.
+ *
+ * Otherwise, create a new loop_variable object to record information about
+ * the variable, and set its \c read_before_write field appropriately based on
+ * \c in_assignee.
+ *
+ * \arg in_assignee is true if this variable was encountered on the LHS of an
+ * assignment.
+ */
+loop_variable *
+loop_variable_state::get_or_insert(ir_variable *var, bool in_assignee)
+{
+   loop_variable *lv = this->get(var);
+
+   if (lv == NULL) {
+      lv = this->insert(var);
+      lv->read_before_write = !in_assignee;
+   }
+
+   return lv;
+}
+
+
 namespace {
 
 class loop_analysis : public ir_hierarchical_visitor {
@@ -157,14 +224,14 @@ loop_analysis::visit(ir_loop_jump *ir)
 ir_visitor_status
 loop_analysis::visit_enter(ir_call *ir)
 {
-   /* If we're not somewhere inside a loop, there's nothing to do. */
-   if (this->state.is_empty())
-      return visit_continue;
-
-   loop_variable_state *const ls =
-      (loop_variable_state *) this->state.get_head();
+   /* Mark every loop that we're currently analyzing as containing an ir_call
+    * (even those at outer nesting levels).
+    */
+   foreach_list(node, &this->state) {
+      loop_variable_state *const ls = (loop_variable_state *) node;
+      ls->contains_calls = true;
+   }
 
-   ls->contains_calls = true;
    return visit_continue_with_parent;
 }
 
@@ -177,35 +244,18 @@ loop_analysis::visit(ir_dereference_variable *ir)
    if (this->state.is_empty())
       return visit_continue;
 
-   loop_variable_state *const ls =
-      (loop_variable_state *) this->state.get_head();
-
-   ir_variable *var = ir->variable_referenced();
-   loop_variable *lv = ls->get(var);
-
-   if (lv == NULL) {
-      lv = ls->insert(var);
-      lv->read_before_write = !this->in_assignee;
-   }
-
-   if (this->in_assignee) {
-      assert(this->current_assignment != NULL);
+   bool nested = false;
 
-      lv->conditional_assignment = (this->if_statement_depth > 0)
-	 || (this->current_assignment->condition != NULL);
+   foreach_list(node, &this->state) {
+      loop_variable_state *const ls = (loop_variable_state *) node;
 
-      if (lv->first_assignment == NULL) {
-	 assert(lv->num_assignments == 0);
-
-	 lv->first_assignment = this->current_assignment;
-      }
+      ir_variable *var = ir->variable_referenced();
+      loop_variable *lv = ls->get_or_insert(var, this->in_assignee);
 
-      lv->num_assignments++;
-   } else if (lv->first_assignment == this->current_assignment) {
-      /* This catches the case where the variable is used in the RHS of an
-       * assignment where it is also in the LHS.
-       */
-      lv->read_before_write = true;
+      lv->record_reference(this->in_assignee,
+                           nested || this->if_statement_depth > 0,
+                           this->current_assignment);
+      nested = true;
    }
 
    return visit_continue;
@@ -286,7 +336,7 @@ loop_analysis::visit_leave(ir_loop *ir)
       foreach_list_safe(node, &ls->variables) {
 	 loop_variable *lv = (loop_variable *) node;
 
-	 if (lv->conditional_assignment || (lv->num_assignments > 1))
+	 if (lv->conditional_or_nested_assignment || (lv->num_assignments > 1))
 	    continue;
 
 	 /* Process the RHS of the assignment.  If all of the variables
@@ -326,9 +376,10 @@ loop_analysis::visit_leave(ir_loop *ir)
       assert(lv->num_assignments == 1);
       assert(lv->first_assignment != NULL);
 
-      /* The assignmnet to the variable in the loop must be unconditional.
+      /* The assignment to the variable in the loop must be unconditional and
+       * not inside a nested loop.
        */
-      if (lv->conditional_assignment)
+      if (lv->conditional_or_nested_assignment)
 	 continue;
 
       /* Basic loop induction variables have a single assignment in the loop
@@ -338,8 +389,6 @@ loop_analysis::visit_leave(ir_loop *ir)
       ir_rvalue *const inc =
 	 get_basic_induction_increment(lv->first_assignment, ls->var_hash);
       if (inc != NULL) {
-	 lv->iv_scale = NULL;
-	 lv->biv = lv->var;
 	 lv->increment = inc;
 
 	 lv->remove();
@@ -347,6 +396,75 @@ loop_analysis::visit_leave(ir_loop *ir)
       }
    }
 
+   /* Search the loop terminating conditions for those of the form 'i < c'
+    * where i is a loop induction variable, c is a constant, and < is any
+    * relative operator.  From each of these we can infer an iteration count.
+    * Also figure out which terminator (if any) produces the smallest
+    * iteration count--this is the limiting terminator.
+    */
+   foreach_list(node, &ls->terminators) {
+      loop_terminator *t = (loop_terminator *) node;
+      ir_if *if_stmt = t->ir;
+
+      /* If-statements can be either 'if (expr)' or 'if (deref)'.  We only care
+       * about the former here.
+       */
+      ir_expression *cond = if_stmt->condition->as_expression();
+      if (cond == NULL)
+	 continue;
+
+      switch (cond->operation) {
+      case ir_binop_less:
+      case ir_binop_greater:
+      case ir_binop_lequal:
+      case ir_binop_gequal: {
+	 /* The expressions that we care about will either be of the form
+	  * 'counter < limit' or 'limit < counter'.  Figure out which is
+	  * which.
+	  */
+	 ir_rvalue *counter = cond->operands[0]->as_dereference_variable();
+	 ir_constant *limit = cond->operands[1]->as_constant();
+	 enum ir_expression_operation cmp = cond->operation;
+
+	 if (limit == NULL) {
+	    counter = cond->operands[1]->as_dereference_variable();
+	    limit = cond->operands[0]->as_constant();
+
+	    switch (cmp) {
+	    case ir_binop_less:    cmp = ir_binop_greater; break;
+	    case ir_binop_greater: cmp = ir_binop_less;    break;
+	    case ir_binop_lequal:  cmp = ir_binop_gequal;  break;
+	    case ir_binop_gequal:  cmp = ir_binop_lequal;  break;
+	    default: assert(!"Should not get here.");
+	    }
+	 }
+
+	 if ((counter == NULL) || (limit == NULL))
+	    break;
+
+	 ir_variable *var = counter->variable_referenced();
+
+	 ir_rvalue *init = find_initial_value(ir, var);
+
+         loop_variable *lv = ls->get(var);
+         if (lv != NULL && lv->is_induction_var()) {
+            t->iterations = calculate_iterations(init, limit, lv->increment,
+                                                 cmp);
+
+            if (t->iterations >= 0 &&
+                (ls->limiting_terminator == NULL ||
+                 t->iterations < ls->limiting_terminator->iterations)) {
+               ls->limiting_terminator = t;
+            }
+         }
+         break;
+      }
+
+      default:
+         break;
+      }
+   }
+
    return visit_continue;
 }