intel/ir: Remove scheduling-based cycle count estimates.

The cycle count estimation logic part of the scheduler is now
redundant with the shader performance modeling pass, and the estimates
can be consolidated into the brw::performance analysis result object
instead of being part of the CFG, which guarantees that the estimates
cannot be accessed without previously calling the
performance_analysis::require() method, which makes sure that the
right analysis pass is executed at the right time if we don't already
have up-to-date cached results.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

src/intel/compiler/brw_cfg.cpp

@@ -63,7 +63,7 @@ push_stack(exec_list *list, void *mem_ctx, bblock_t *block)
 }
 
 bblock_t::bblock_t(cfg_t *cfg) :
-   cfg(cfg), start_ip(0), end_ip(0), num(0), cycle_count(0)
+   cfg(cfg), start_ip(0), end_ip(0), num(0)
 {
    instructions.make_empty();
    parents.make_empty();
@@ -173,7 +173,6 @@ cfg_t::cfg_t(const backend_shader *s, exec_list *instructions) :
    block_list.make_empty();
    blocks = NULL;
    num_blocks = 0;
-   cycle_count = 0;
 
    bblock_t *cur = NULL;
    int ip = 0;

src/intel/compiler/brw_cfg.h

@@ -119,8 +119,6 @@ struct bblock_t {
    struct exec_list parents;
    struct exec_list children;
    int num;
-
-   unsigned cycle_count;
 };
 
 static inline struct backend_instruction *
@@ -329,8 +327,6 @@ struct cfg_t {
    struct exec_list block_list;
    struct bblock_t **blocks;
    int num_blocks;
-
-   unsigned cycle_count;
 };
 
 static inline struct bblock_t *

src/intel/compiler/brw_schedule_instructions.cpp

@@ -1762,24 +1762,6 @@ instruction_scheduler::schedule_instructions(bblock_t *block)
    }
 
    assert(instructions_to_schedule == 0);
-
-   block->cycle_count = time;
-}
-
-static unsigned get_cycle_count(cfg_t *cfg)
-{
-   unsigned count = 0, multiplier = 1;
-   foreach_block(block, cfg) {
-      if (block->start()->opcode == BRW_OPCODE_DO)
-         multiplier *= 10; /* assume that loops execute ~10 times */
-
-      count += block->cycle_count * multiplier;
-
-      if (block->end()->opcode == BRW_OPCODE_WHILE)
-         multiplier /= 10;
-   }
-
-   return count;
 }
 
 void
@@ -1821,8 +1803,6 @@ instruction_scheduler::run(cfg_t *cfg)
               post_reg_alloc);
       bs->dump_instructions();
    }
-
-   cfg->cycle_count = get_cycle_count(cfg);
 }
 
 void