ir_to_mesa: Handle loops with loop controls set

The downside of our talloc usage is that we can't really make static
(i.e., not created with new) instances of our IR types.  This leads to
a lot of unnecessary dynamic allocation in this patch.

diff --git a/src/mesa/program/ir_to_mesa.cpp b/src/mesa/program/ir_to_mesa.cpp
index f0e14b8ece33b459312a3979d76ed404e2648c41..839d6f0467379aef1bfe248bca8a6a1ab84de7f6 100644 (file)
--- a/src/mesa/program/ir_to_mesa.cpp
+++ b/src/mesa/program/ir_to_mesa.cpp
@@ -882,13 +882,53 @@ ir_to_mesa_visitor::visit(ir_variable *ir)
 void
 ir_to_mesa_visitor::visit(ir_loop *ir)
 {
-   assert(!ir->from);
-   assert(!ir->to);
-   assert(!ir->increment);
-   assert(!ir->counter);
+   ir_dereference_variable *counter = NULL;
+
+   if (ir->counter != NULL)
+      counter = new(ir) ir_dereference_variable(ir->counter);
+
+   if (ir->from != NULL) {
+      assert(ir->counter != NULL);
+
+      ir_assignment *a = new(ir) ir_assignment(counter, ir->from, NULL);
+
+      a->accept(this);
+      delete a;
+   }
 
    ir_to_mesa_emit_op0(NULL, OPCODE_BGNLOOP);
+
+   if (ir->to) {
+      ir_expression *e =
+        new(ir) ir_expression(ir->cmp, glsl_type::bool_type,
+                              counter, ir->to);
+      ir_if *if_stmt =  new(ir) ir_if(e);
+
+      ir_loop_jump *brk = new(ir) ir_loop_jump(ir_loop_jump::jump_break);
+
+      if_stmt->then_instructions.push_tail(brk);
+
+      if_stmt->accept(this);
+
+      delete if_stmt;
+      delete e;
+      delete brk;
+   }
+
    visit_exec_list(&ir->body_instructions, this);
+
+   if (ir->increment) {
+      ir_expression *e =
+        new(ir) ir_expression(ir_binop_add, counter->type,
+                              counter, ir->increment);
+
+      ir_assignment *a = new(ir) ir_assignment(counter, e, NULL);
+
+      a->accept(this);
+      delete a;
+      delete e;
+   }
+
    ir_to_mesa_emit_op0(NULL, OPCODE_ENDLOOP);
 }