Matt Turner <matts...@gmail.com> writes: > Removes IF/ENDIF and IF/ELSE/ENDIF with no intervening instructions. > > total instructions in shared programs: 1360393 -> 1360387 (-0.00%) > instructions in affected programs: 157 -> 151 (-3.82%) > > (no change in vertex shaders) > > Reviewed-by: Paul Berry <stereotype...@gmail.com> [v1] > v2: Moved before SEL peephole in series. Made function useful for VS.
> +bool
> +dead_control_flow_eliminate(backend_visitor *v)
> +{
> + bool progress = false;
> +
> + cfg_t cfg(v);
> +
> + for (int b = 0; b < cfg.num_blocks; b++) {
> + bblock_t *block = cfg.blocks[b];
> + bool found = false;
> +
> + /* ENDIF instructions, by definition, can only be found at the ends of
> + * basic blocks.
> + */
> + backend_instruction *endif_inst = block->end;
> + if (endif_inst->opcode != BRW_OPCODE_ENDIF)
> + continue;
> +
> + backend_instruction *if_inst = NULL, *else_inst = NULL;
> + backend_instruction *prev_inst = (backend_instruction *)
> endif_inst->prev;
> + if (prev_inst->opcode == BRW_OPCODE_IF) {
> + if_inst = prev_inst;
> + found = true;
> + } else if (prev_inst->opcode == BRW_OPCODE_ELSE) {
> + else_inst = prev_inst;
> +
> + prev_inst = (backend_instruction *) prev_inst->prev;
> + if (prev_inst->opcode == BRW_OPCODE_IF) {
> + if_inst = prev_inst;
> + found = true;
> + }
> + }
> +
> + if (found) {
> + if_inst->remove();
> + if (else_inst)
> + else_inst->remove();
> + endif_inst->remove();
> + progress = true;
> + }
> + }
Since you've modified the ip of instructions, this needs
if (progress)
invalidate_live_intervals();
> +
> + return progress;
Other than that,
Reviewed-by: Eric Anholt <e...@anholt.net>
pgpB_8H18m9h8.pgp
Description: PGP signature
_______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
