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| author | Jakub Jelinek <jakub@redhat.com> | 2019-04-29 16:18:55 +0200 |
|---|---|---|
| committer | Jakub Jelinek <jakub@gcc.gnu.org> | 2019-04-29 16:18:55 +0200 |
| commit | 1008df90cca4a4f49f2a898115f8756fafff3187 (patch) | |
| tree | 65b74e56f1a118c9e0f26cb15c7ca45a6794cce3 | |
| parent | 4e29671cb258f486e498a0697f88861ff351de50 (diff) | |
| download | gcc-1008df90cca4a4f49f2a898115f8756fafff3187.zip gcc-1008df90cca4a4f49f2a898115f8756fafff3187.tar.gz gcc-1008df90cca4a4f49f2a898115f8756fafff3187.tar.bz2 | |
re PR rtl-optimization/90257 (8% degradation on cpu2006 403.gcc starting with r270484)
PR rtl-optimization/90257
* cfgrtl.c (flow_active_insn_p): Return true for USE of a function
return value.
Revert the revert:
2019-04-21 H.J. Lu <hongjiu.lu@intel.com>
PR target/90178
Revert:
2018-11-21 Uros Bizjak <ubizjak@gmail.com>
Revert the revert:
2013-10-26 Vladimir Makarov <vmakarov@redhat.com>
Revert:
2013-10-25 Vladimir Makarov <vmakarov@redhat.com>
* lra-spills.c (lra_final_code_change): Remove useless move insns.
From-SVN: r270653
| -rw-r--r-- | gcc/ChangeLog | 21 | ||||
| -rw-r--r-- | gcc/cfgrtl.c | 10 | ||||
| -rw-r--r-- | gcc/lra-spills.c | 15 |
3 files changed, 43 insertions, 3 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index b1c68bb..0c2b51a 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,24 @@ +2019-04-29 Jakub Jelinek <jakub@redhat.com> + + PR rtl-optimization/90257 + * cfgrtl.c (flow_active_insn_p): Return true for USE of a function + return value. + + Revert the revert: + 2019-04-21 H.J. Lu <hongjiu.lu@intel.com> + + PR target/90178 + Revert: + 2018-11-21 Uros Bizjak <ubizjak@gmail.com> + + Revert the revert: + 2013-10-26 Vladimir Makarov <vmakarov@redhat.com> + + Revert: + 2013-10-25 Vladimir Makarov <vmakarov@redhat.com> + + * lra-spills.c (lra_final_code_change): Remove useless move insns. + 2019-04-29 Richard Biener <rguenther@suse.de> * tree-ssa.c (insert_debug_temp_for_var_def): For {CLOBBER} diff --git a/gcc/cfgrtl.c b/gcc/cfgrtl.c index 08e534f..e06fb8d 100644 --- a/gcc/cfgrtl.c +++ b/gcc/cfgrtl.c @@ -543,7 +543,7 @@ update_bb_for_insn (basic_block bb) } -/* Like active_insn_p, except keep the return value clobber around +/* Like active_insn_p, except keep the return value use or clobber around even after reload. */ static bool @@ -556,8 +556,12 @@ flow_active_insn_p (const rtx_insn *insn) programs that fail to return a value. Its effect is to keep the return value from being live across the entire function. If we allow it to be skipped, we introduce the - possibility for register lifetime confusion. */ - if (GET_CODE (PATTERN (insn)) == CLOBBER + possibility for register lifetime confusion. + Similarly, keep a USE of the function return value, otherwise + the USE is dropped and we could fail to thread jump if USE + appears on some paths and not on others, see PR90257. */ + if ((GET_CODE (PATTERN (insn)) == CLOBBER + || GET_CODE (PATTERN (insn)) == USE) && REG_P (XEXP (PATTERN (insn), 0)) && REG_FUNCTION_VALUE_P (XEXP (PATTERN (insn), 0))) return true; diff --git a/gcc/lra-spills.c b/gcc/lra-spills.c index 18db79e7..c19b76a 100644 --- a/gcc/lra-spills.c +++ b/gcc/lra-spills.c @@ -740,6 +740,7 @@ lra_final_code_change (void) int i, hard_regno; basic_block bb; rtx_insn *insn, *curr; + rtx set; int max_regno = max_reg_num (); for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++) @@ -818,5 +819,19 @@ lra_final_code_change (void) } if (insn_change_p) lra_update_operator_dups (id); + + if ((set = single_set (insn)) != NULL + && REG_P (SET_SRC (set)) && REG_P (SET_DEST (set)) + && REGNO (SET_SRC (set)) == REGNO (SET_DEST (set))) + { + /* Remove an useless move insn. 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); + } } } |