diff options
| author | Matt Turner <[email protected]> | 2014-05-17 11:53:45 -0700 |
|---|---|---|
| committer | Matt Turner <[email protected]> | 2014-05-24 23:03:22 -0700 |
| commit | dd0e1c3aff0193bc130161e6f4d13042a7d83bae (patch) | |
| tree | fefbb15f4b154ca9adeb51c6814244e28dc90e40 | |
| parent | 04ce3be4010305902cc5ae81e8e0c8550d043a1e (diff) | |
i965/cfg: Make DO instruction begin a basic block.
The DO instruction doesn't exist on Gen6+. Since before this commit, DO
always ended a basic block, if it also happened to start one (e.g., a
while loop inside an if statement) the block containing only the DO
would actually contain no hardware instructions.
Pre-Gen6's WHILE instructions jumps to the instruction following the DO,
so strictly speaking we won't be modeling that properly, but I claim
there is actually no functional difference.
This will simplify an upcoming change where we want to mark the first
hardware instruction in the loop as beginning a block, and the last
instruction before the loop as ending one.
Reviewed-by: Eric Anholt <[email protected]>
| -rw-r--r-- | src/mesa/drivers/dri/i965/brw_cfg.cpp | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/src/mesa/drivers/dri/i965/brw_cfg.cpp b/src/mesa/drivers/dri/i965/brw_cfg.cpp index a806714c203..6bf99f17f58 100644 --- a/src/mesa/drivers/dri/i965/brw_cfg.cpp +++ b/src/mesa/drivers/dri/i965/brw_cfg.cpp @@ -98,7 +98,7 @@ cfg_t::cfg_t(exec_list *instructions) bblock_t *cur_if = NULL; /**< BB ending with IF. */ bblock_t *cur_else = NULL; /**< BB ending with ELSE. */ bblock_t *cur_endif = NULL; /**< BB starting with ENDIF. */ - bblock_t *cur_do = NULL; /**< BB ending with DO. */ + bblock_t *cur_do = NULL; /**< BB starting with DO. */ bblock_t *cur_while = NULL; /**< BB immediately following WHILE. */ exec_list if_stack, else_stack, do_stack, while_stack; bblock_t *next; @@ -205,15 +205,18 @@ cfg_t::cfg_t(exec_list *instructions) */ cur_while = new_block(); - /* Set up our immediately following block, full of "then" - * instructions. - */ - next = new_block(); - next->start = (backend_instruction *)inst->next; - cur->add_successor(mem_ctx, next); - cur_do = next; + if (cur->start == inst) { + /* New block was just created; use it. */ + cur_do = cur; + } else { + cur_do = new_block(); + cur_do->start = inst; - set_next_block(&cur, next, ip); + cur->end = (backend_instruction *)inst->prev; + cur->add_successor(mem_ctx, cur_do); + + set_next_block(&cur, cur_do, ip - 1); + } break; case BRW_OPCODE_CONTINUE: |