i965: Remove the create_raw_surface vtbl hook.

[mesa.git] / src / mesa / drivers / dri / i965 / brw_fs_peephole_predicated_break.cpp

diff --git a/src/mesa/drivers/dri/i965/brw_fs_peephole_predicated_break.cpp b/src/mesa/drivers/dri/i965/brw_fs_peephole_predicated_break.cpp
index 802b8de54b2058389d070e6c6dca5c12e998e96e..047c2c0b1cf5f0e75d9ff9d13cb4133ec3dfbc61 100644 (file)
--- a/src/mesa/drivers/dri/i965/brw_fs_peephole_predicated_break.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_peephole_predicated_break.cpp
@@ -38,6 +38,18 @@
  *
  * This peephole pass removes the IF and ENDIF instructions and predicates the
  * BREAK, dropping two instructions from the loop body.
+ *
+ * If the loop was a DO { ... } WHILE loop, it looks like
+ *
+ * loop:
+ *    ...
+ *    CMP.f0
+ *    (+f0) IF
+ *    BREAK
+ *    ENDIF
+ *    WHILE loop
+ *
+ * and we can remove the BREAK instruction and predicate the WHILE.
  */
 
 bool
@@ -57,17 +69,17 @@ fs_visitor::opt_peephole_predicated_break()
           jump_inst->opcode != BRW_OPCODE_CONTINUE)
          continue;
 
-      fs_inst *if_inst = (fs_inst *)((bblock_t *)block->link.prev)->end();
+      fs_inst *if_inst = (fs_inst *)block->prev()->end();
       if (if_inst->opcode != BRW_OPCODE_IF)
          continue;
 
-      fs_inst *endif_inst = (fs_inst *)((bblock_t *)block->link.next)->start();
+      fs_inst *endif_inst = (fs_inst *)block->next()->start();
       if (endif_inst->opcode != BRW_OPCODE_ENDIF)
          continue;
 
       bblock_t *jump_block = block;
-      bblock_t *if_block = (bblock_t *)jump_block->link.prev;
-      bblock_t *endif_block = (bblock_t *)jump_block->link.next;
+      bblock_t *if_block = jump_block->prev();
+      bblock_t *endif_block = jump_block->next();
 
       /* For Sandybridge with IF with embedded comparison we need to emit an
        * instruction to set the flag register.
@@ -84,21 +96,25 @@ fs_visitor::opt_peephole_predicated_break()
 
       bblock_t *earlier_block = if_block;
       if (if_block->start_ip == if_block->end_ip) {
-         earlier_block = (bblock_t *)if_block->link.prev;
+         earlier_block = if_block->prev();
       }
 
       if_inst->remove(if_block);
 
       bblock_t *later_block = endif_block;
       if (endif_block->start_ip == endif_block->end_ip) {
-         later_block = (bblock_t *)endif_block->link.next;
+         later_block = endif_block->next();
       }
       endif_inst->remove(endif_block);
 
-      earlier_block->children.make_empty();
-      later_block->parents.make_empty();
+      if (!earlier_block->ends_with_control_flow()) {
+         earlier_block->children.make_empty();
+         earlier_block->add_successor(cfg->mem_ctx, jump_block);
+      }
 
-      earlier_block->add_successor(cfg->mem_ctx, jump_block);
+      if (!later_block->starts_with_control_flow()) {
+         later_block->parents.make_empty();
+      }
       jump_block->add_successor(cfg->mem_ctx, later_block);
 
       if (earlier_block->can_combine_with(jump_block)) {
@@ -107,6 +123,30 @@ fs_visitor::opt_peephole_predicated_break()
          block = earlier_block;
       }
 
+      /* Now look at the first instruction of the block following the BREAK. If
+       * it's a WHILE, we can delete the break, predicate the WHILE, and join
+       * the two basic blocks.
+       */
+      bblock_t *while_block = earlier_block->next();
+      fs_inst *while_inst = (fs_inst *)while_block->start();
+
+      if (jump_inst->opcode == BRW_OPCODE_BREAK &&
+          while_inst->opcode == BRW_OPCODE_WHILE &&
+          while_inst->predicate == BRW_PREDICATE_NONE) {
+         jump_inst->remove(earlier_block);
+         while_inst->predicate = jump_inst->predicate;
+         while_inst->predicate_inverse = !jump_inst->predicate_inverse;
+
+         earlier_block->children.make_empty();
+         earlier_block->add_successor(cfg->mem_ctx, while_block);
+
+         assert(earlier_block->can_combine_with(while_block));
+         earlier_block->combine_with(while_block);
+
+         earlier_block->next()->parents.make_empty();
+         earlier_block->add_successor(cfg->mem_ctx, earlier_block->next());
+      }
+
       progress = true;
    }