2011/8/4 Richard Henderson <r...@redhat.com>: > When a frame pointer is in use, we can optimize popping all > queued parameters via a simple move from the frame pointer > instead of an addition to the stack pointer. > > The new sequence is 4 insns, the old sequence was 9 insns. > > Committed.
It seems strange for me: +;; Notice a special-case when adding N to SP where N results in a +;; zero REG_ARGS_SIZE. This is equivalent to a move from FP. +(define_split + [(set (reg:HI REG_SP) (match_operand:HI 0 "register_operand" ""))] + "reload_completed + && frame_pointer_needed + && !cfun->calls_alloca + && find_reg_note (insn, REG_ARGS_SIZE, const0_rtx)" + [(set (reg:HI REG_SP) (reg:HI REG_Y))] + "") What is it ? ... It's a transition from SP = general-register to SP = REG_Y with set of conditions. Generally, it's seems wrong (SP = REG) isn't equal to (SP = REG_Y). Denis.
