fdo-mirrors/mesa
1
0
Fork 0
mirror of https://gitlab.freedesktop.org/mesa/mesa.git synced 2025-12-28 08:10:09 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

i965/fs: Preserve CFG in predicated break pass.

Browse source 
Operating on this code,

B0: ...
    cmp.ne.f0(8)
    (+f0) if(8)
B1: break(8)
B2: endif(8)

We can delete B2 without attempting to merge any blocks, since the
break/continue instruction necessarily ends the previous block.

After deleting the if instruction, we attempt to merge blocks B0 and B1.

Reviewed-by: Topi Pohjolainen <topi.pohjolainen@intel.com>
This commit is contained in:
Matt Turner 2014-07-17 10:50:31 -07:00
parent 3c4c2a6e30
commit b8aa1005c8
1 changed files with 25 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

29
src/mesa/drivers/dri/i965/brw_fs_peephole_predicated_break.cpp
View file

@ -64,27 +64,48 @@ fs_visitor::opt_peephole_predicated_break()
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;
/* For Sandybridge with IF with embedded comparison we need to emit an
* instruction to set the flag register.
*/
if (brw->gen == 6 && if_inst->conditional_mod) {
fs_inst *cmp_inst = CMP(reg_null_d, if_inst->src[0], if_inst->src[1],
if_inst->conditional_mod);
if_inst->insert_before(cmp_inst);
if_inst->insert_before(if_block, cmp_inst);
jump_inst->predicate = BRW_PREDICATE_NORMAL;
} else {
jump_inst->predicate = if_inst->predicate;
jump_inst->predicate_inverse = if_inst->predicate_inverse;
}
if_inst->remove();
endif_inst->remove();
bblock_t *earlier_block = if_block;
if (if_block->start_ip == if_block->end_ip) {
earlier_block = (bblock_t *)if_block->link.prev;
}
if_inst->remove(if_block);
endif_inst->remove(endif_block);
if_block->children.make_empty();
endif_block->parents.make_empty();
if_block->add_successor(cfg->mem_ctx, jump_block);
jump_block->add_successor(cfg->mem_ctx, endif_block);
if (earlier_block->can_combine_with(jump_block)) {
earlier_block->combine_with(jump_block);
block = earlier_block;
}
progress = true;
}
if (progress)
invalidate_live_intervals();
invalidate_live_intervals(false);
return progress;
}