Module: Mesa Branch: master Commit: 219b43c612b2882e0bf82ac1a12ff073a42be6e1 URL: http://cgit.freedesktop.org/mesa/mesa/commit/?id=219b43c612b2882e0bf82ac1a12ff073a42be6e1
Author: Matt Turner <[email protected]> Date: Tue Oct 22 15:40:08 2013 -0700 i965/fs: Don't emit null MOVs in CSE. We'd like to CSE some instructions, like CMP, that often have null destinations. Instead of replacing them with MOVs to null, just don't emit the MOV. Reviewed-by: Paul Berry <[email protected]> --- src/mesa/drivers/dri/i965/brw_fs_cse.cpp | 42 +++++++++++++++++------------ 1 files changed, 25 insertions(+), 17 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_fs_cse.cpp b/src/mesa/drivers/dri/i965/brw_fs_cse.cpp index 0afc5f6..3f59339 100644 --- a/src/mesa/drivers/dri/i965/brw_fs_cse.cpp +++ b/src/mesa/drivers/dri/i965/brw_fs_cse.cpp @@ -150,7 +150,7 @@ fs_visitor::opt_cse_local(bblock_t *block, exec_list *aeb) * If we don't have a temporary already, make one. */ bool no_existing_temp = entry->tmp.file == BAD_FILE; - if (no_existing_temp) { + if (no_existing_temp && !entry->generator->dst.is_null()) { int written = entry->generator->regs_written; fs_reg orig_dst = entry->generator->dst; @@ -171,29 +171,37 @@ fs_visitor::opt_cse_local(bblock_t *block, exec_list *aeb) } /* dest <- temp */ - int written = inst->regs_written; - assert(written == entry->generator->regs_written); - assert(inst->dst.type == entry->tmp.type); - fs_reg dst = inst->dst; - fs_reg tmp = entry->tmp; - fs_inst *copy = NULL; - for (int i = 0; i < written; i++) { - copy = MOV(dst, tmp); - copy->force_writemask_all = inst->force_writemask_all; - inst->insert_before(copy); - - dst.reg_offset++; - tmp.reg_offset++; + if (!inst->dst.is_null()) { + int written = inst->regs_written; + assert(written == entry->generator->regs_written); + assert(inst->dst.type == entry->tmp.type); + fs_reg dst = inst->dst; + fs_reg tmp = entry->tmp; + fs_inst *copy = NULL; + for (int i = 0; i < written; i++) { + copy = MOV(dst, tmp); + copy->force_writemask_all = inst->force_writemask_all; + inst->insert_before(copy); + + dst.reg_offset++; + tmp.reg_offset++; + } } + + /* Set our iterator so that next time through the loop inst->next + * will get the instruction in the basic block after the one we've + * removed. + */ + fs_inst *prev = (fs_inst *)inst->prev; + inst->remove(); /* Appending an instruction may have changed our bblock end. */ if (inst == block->end) { - block->end = copy; + block->end = prev; } - /* Continue iteration with copy->next */ - inst = copy; + inst = prev; } } _______________________________________________ mesa-commit mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/mesa-commit
