summaryrefslogtreecommitdiffstats
path: root/src/mesa
diff options
context:
space:
mode:
authorIan Romanick <[email protected]>2016-02-24 19:26:13 -0800
committerIan Romanick <[email protected]>2016-02-26 16:51:27 -0800
commitc7deee69ea6f64ea5b563985bf19d9deebe73b5b (patch)
tree68a7d3e931d8ee1c1f46430b9a088ed0d94ce572 /src/mesa
parent70cf0eb5c72c8115b1d2fe6532c97640b4043c0c (diff)
i965/cfg: Track prev_block and prev_inst explicitly in the whole function
This provides a trivial simplification now, and it makes some future changes more straight forward. Signed-off-by: Ian Romanick <[email protected]> Reviewed-by: Francisco Jerez <[email protected]>
Diffstat (limited to 'src/mesa')
-rw-r--r--src/mesa/drivers/dri/i965/brw_dead_control_flow.cpp12
1 files changed, 7 insertions, 5 deletions
diff --git a/src/mesa/drivers/dri/i965/brw_dead_control_flow.cpp b/src/mesa/drivers/dri/i965/brw_dead_control_flow.cpp
index 716e2bc25ba..7aa72b1b413 100644
--- a/src/mesa/drivers/dri/i965/brw_dead_control_flow.cpp
+++ b/src/mesa/drivers/dri/i965/brw_dead_control_flow.cpp
@@ -41,7 +41,9 @@ dead_control_flow_eliminate(backend_shader *s)
bool progress = false;
foreach_block_safe (block, s->cfg) {
+ bblock_t *prev_block = block->prev();
backend_instruction *const inst = block->start();
+ backend_instruction *prev_inst = prev_block->end();
/* ENDIF instructions, by definition, can only be found at the start of
* basic blocks.
@@ -52,20 +54,20 @@ dead_control_flow_eliminate(backend_shader *s)
backend_instruction *endif_inst = inst;
backend_instruction *if_inst = NULL, *else_inst = NULL;
- backend_instruction *prev_inst = endif_block->prev()->end();
if (prev_inst->opcode == BRW_OPCODE_ELSE) {
else_inst = prev_inst;
else_block = endif_block->prev();
found = true;
- if (else_block->start_ip == else_block->end_ip)
- prev_inst = else_block->prev()->end();
+ if (else_block->start_ip == else_block->end_ip) {
+ prev_block = prev_block->prev();
+ prev_inst = prev_block->end();
+ }
}
if (prev_inst->opcode == BRW_OPCODE_IF) {
if_inst = prev_inst;
- if_block = else_block != NULL ? else_block->prev()
- : endif_block->prev();
+ if_block = prev_block;
found = true;
} else {
/* Don't remove the ENDIF if we didn't find a dead IF. */