From e697148cb05240b68764232fb1d47d2acbdcfb3b Mon Sep 17 00:00:00 2001 From: Vladimir Makarov Date: Mon, 28 Oct 2013 23:15:12 +0000 Subject: [PATCH] lra-spills.c (lra_final_code_change): Remove useless move insns originated from moves of pseudos. 2013-10-28 Vladimir Makarov * lra-spills.c (lra_final_code_change): Remove useless move insns originated from moves of pseudos. From-SVN: r204140 --- gcc/ChangeLog | 5 +++++ gcc/lra-spills.c | 24 +++++++++++++++++++++++- 2 files changed, 28 insertions(+), 1 deletion(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 013fe7399a7..70193b49d13 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2013-10-28 Vladimir Makarov + + * lra-spills.c (lra_final_code_change): Remove useless move insns + originated from moves of pseudos. + 2013-10-28 Jeff Law * lower-subreg.c (resolve_simple_move): Fix comment typo. diff --git a/gcc/lra-spills.c b/gcc/lra-spills.c index 7c0c630273d..7690fbc0ab1 100644 --- a/gcc/lra-spills.c +++ b/gcc/lra-spills.c @@ -625,7 +625,7 @@ lra_final_code_change (void) { int i, hard_regno; basic_block bb; - rtx insn, curr; + rtx insn, curr, set; int max_regno = max_reg_num (); for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++) @@ -636,6 +636,7 @@ lra_final_code_change (void) FOR_BB_INSNS_SAFE (bb, insn, curr) if (INSN_P (insn)) { + bool change_p; rtx pat = PATTERN (insn); if (GET_CODE (pat) == CLOBBER && LRA_TEMP_CLOBBER_P (pat)) @@ -648,6 +649,12 @@ lra_final_code_change (void) continue; } + set = single_set (insn); + change_p = (set != NULL + && REG_P (SET_SRC (set)) && REG_P (SET_DEST (set)) + && REGNO (SET_SRC (set)) >= FIRST_PSEUDO_REGISTER + && REGNO (SET_DEST (set)) >= FIRST_PSEUDO_REGISTER); + lra_insn_recog_data_t id = lra_get_insn_recog_data (insn); struct lra_static_insn_data *static_id = id->insn_static_data; bool insn_change_p = false; @@ -661,5 +668,20 @@ lra_final_code_change (void) } if (insn_change_p) lra_update_operator_dups (id); + + if (change_p && REGNO (SET_SRC (set)) == REGNO (SET_DEST (set))) + { + /* Remove an useless move insn but only involving + pseudos as some subsequent optimizations are based on + that move insns involving originally hard registers + are preserved. IRA can generate move insns involving + pseudos. It is better remove them earlier to speed + up compiler a bit. It is also better to do it here + as they might not pass final RTL check in LRA, + (e.g. insn moving a control register into + itself). */ + lra_invalidate_insn_data (insn); + delete_insn (insn); + } } } -- 2.30.2