From: Paolo Bonzini <bonzini@gnu.org>
To: gcc-patches@gcc.gnu.org
Subject: Re: RFC patch: invariant addresses too cheap
Date: Sat, 31 Oct 2009 11:14:00 -0000 [thread overview]
Message-ID: <hch59e$tpv$1@ger.gmane.org> (raw)
In-Reply-To: <878werq41v.fsf@firetop.home>
On 10/31/2009 10:57 AM, Richard Sandiford wrote:
> So either I need to hack MIPS so that
> 2 is cheap and 3+ is "expensive", or we need some better way
> of determining this.
- return mips_address_insns (addr, SImode, false);
+ int insns = mips_address_insns (addr, SImode, false);
+ return insns == 1 ? 1 : COSTS_N_INSNS (insns - 1);
?
> I don't think sticking an x86-specific magic number in the
> middle of generic code is acceptable, regardless of how big
> the comment above it is. ;)
That's why I suggested using "<= COSTS_N_INSNS (1) / 2" instead of "<
3". Also ix86-specific calibration, but not so brutally. :-)
Paolo
next prev parent reply other threads:[~2009-10-31 10:59 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-10-19 16:17 Michael Matz
2009-10-19 16:45 ` Paolo Bonzini
2009-10-20 9:04 ` Richard Guenther
2009-10-20 12:07 ` Paolo Bonzini
2009-10-20 16:00 ` Michael Matz
2009-10-20 16:06 ` Richard Guenther
2009-10-31 10:05 ` Richard Sandiford
2009-10-31 11:14 ` Paolo Bonzini [this message]
2009-10-31 11:16 ` Richard Guenther
2009-10-31 12:56 ` Paolo Bonzini
2009-10-31 13:53 ` Richard Sandiford
2009-10-31 14:31 ` Paolo Bonzini
2009-11-01 10:24 ` Richard Sandiford
2009-11-01 10:25 ` Paolo Bonzini
2009-11-14 11:19 ` Richard Sandiford
2009-11-15 16:50 ` Paolo Bonzini
2009-11-15 21:36 ` Richard Sandiford
2009-11-28 10:53 ` Richard Sandiford
2009-12-01 13:05 ` Michael Matz
2009-12-02 22:24 ` Richard Sandiford
2009-12-03 12:57 ` Michael Matz
2009-11-17 18:02 ` Mark Mitchell
2009-10-31 19:23 ` Michael Matz
2009-11-01 10:13 ` Richard Sandiford
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