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From: "kkojima at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/49263] SH Target: underutilized "TST #imm, R0" instruction
Date: Sun, 12 Jun 2011 23:12:00 -0000 [thread overview]
Message-ID: <bug-49263-4-tGqjdfUXpw@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-49263-4@http.gcc.gnu.org/bugzilla/>
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49263
Kazumoto Kojima <kkojima at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target| |sh*-*-*
--- Comment #2 from Kazumoto Kojima <kkojima at gcc dot gnu.org> 2011-06-12 23:11:19 UTC ---
It looks that playing with the internal behavior of the combine
pass is a bit fragile. Perhaps an alternative way is to define
a peephole for tst #imm8,r0, something like:
;; A peephole for the TST immediate instruction.
(define_peephole2
[(set (match_operand:SI 2 "arith_reg_operand" "r")
(and:SI (match_operand:SI 0 "arith_reg_operand" "z")
(match_operand:SI 1 "const_int_operand" "i")))
(set (reg:SI T_REG) (eq:SI (match_dup 2) (const_int 0)))]
"TARGET_SH1
&& peep2_reg_dead_p (2, operands[2])
&& (satisfies_constraint_I08 (operands[1])
|| satisfies_constraint_K08 (operands[1]))"
[(set (reg:SI T_REG)
(eq:SI (and:SI (match_dup 0) (match_dup 1)) (const_int 0)))]
"
{
operands[1] = GEN_INT (INTVAL (operands[1]) & 0xff);
}")
which will work at -O2 or -fpeephole2, though there are pros
and cons of peephole approach.
next prev parent reply other threads:[~2011-06-12 23:12 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-06-01 20:17 [Bug target/49263] New: " oleg.endo@t-online.de
2011-06-01 20:42 ` [Bug target/49263] " oleg.endo@t-online.de
2011-06-12 23:12 ` kkojima at gcc dot gnu.org [this message]
2011-06-19 16:42 ` oleg.endo@t-online.de
2011-06-22 22:34 ` kkojima at gcc dot gnu.org
2011-06-26 22:31 ` oleg.endo@t-online.de
2011-06-27 5:15 ` kkojima at gcc dot gnu.org
2011-10-09 23:35 ` oleg.endo@t-online.de
2011-10-10 1:32 ` kkojima at gcc dot gnu.org
2011-10-10 23:48 ` oleg.endo@t-online.de
2011-10-11 1:47 ` kkojima at gcc dot gnu.org
2011-10-13 22:55 ` oleg.endo@t-online.de
2011-10-14 23:06 ` kkojima at gcc dot gnu.org
2011-10-15 2:33 ` kkojima at gcc dot gnu.org
2011-11-20 14:20 ` oleg.endo@t-online.de
2011-12-29 1:09 ` oleg.endo@t-online.de
2012-02-26 16:28 ` olegendo at gcc dot gnu.org
2012-02-26 23:29 ` olegendo at gcc dot gnu.org
2012-08-27 19:52 ` olegendo at gcc dot gnu.org
2012-10-28 22:02 ` olegendo at gcc dot gnu.org
2012-10-31 13:47 ` olegendo at gcc dot gnu.org
2013-12-08 13:47 ` olegendo at gcc dot gnu.org
2013-12-17 12:37 ` olegendo at gcc dot gnu.org
2014-12-30 18:45 ` olegendo at gcc dot gnu.org
2015-01-24 13:05 ` olegendo at gcc dot gnu.org
2015-01-26 23:57 ` olegendo at gcc dot gnu.org
2023-05-12 11:46 ` klepikov.alex+bugs at gmail dot com
2023-05-23 12:34 ` klepikov.alex+bugs at gmail dot com
2023-05-23 12:35 ` klepikov.alex+bugs at gmail dot com
2023-05-23 19:05 ` olegendo at gcc dot gnu.org
2023-05-24 11:40 ` klepikov.alex+bugs at gmail dot com
2023-05-24 11:57 ` olegendo at gcc dot gnu.org
2023-05-24 13:34 ` klepikov.alex+bugs at gmail dot com
2023-05-24 15:00 ` olegendo at gcc dot gnu.org
2023-05-25 17:53 ` klepikov.alex+bugs at gmail dot com
2023-05-25 21:32 ` olegendo at gcc dot gnu.org
2023-05-26 12:03 ` klepikov.alex+bugs at gmail dot com
2023-05-26 17:44 ` olegendo at gcc dot gnu.org
2023-05-28 10:24 ` klepikov.alex+bugs at gmail dot com
2023-05-28 10:48 ` olegendo at gcc dot gnu.org
2023-05-29 14:54 ` klepikov.alex+bugs at gmail dot com
2023-05-30 1:48 ` egallager at gcc dot gnu.org
2023-05-30 1:56 ` olegendo at gcc dot gnu.org
2023-05-30 12:42 ` klepikov.alex+bugs at gmail dot com
2023-05-30 19:57 ` olegendo at gcc dot gnu.org
2023-05-30 20:00 ` olegendo at gcc dot gnu.org
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