From: Avi Kivity <avi@redhat.com>
To: Andi Kleen <andi@firstfloor.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
QEMU Developers <qemu-devel@nongnu.org>
Subject: Re: [Qemu-devel] [PATCH 5/8] tcg: Add interpreter for bytecode
Date: Mon, 19 Sep 2011 14:56:17 +0300 [thread overview]
Message-ID: <4E772DE1.2090407@redhat.com> (raw)
In-Reply-To: <51221ff5190e1823f0d6b602c4ca0f4d.squirrel@www.firstfloor.org>
On 09/19/2011 09:52 AM, Andi Kleen wrote:
> > I think it also improves branch target prediction - if you have a tight
> > loop of a few opcodes the predictor can guess where you're headed (since
> > there is a separate lookup key for each opcode), whereas with the
> > original code, there's a single key which cannot be used to predict the
> > branch target.
>
> At least usually. I caught at least one version of gcc to CSE the jump
> instruction into a common location in one of my interpreters
> :-( But not all do it at least, and I hope gcc gets fixed.
You generally want CSE, yes? So you can't blame gcc for getting it
wrong sometimes.
--
error compiling committee.c: too many arguments to function
next prev parent reply other threads:[~2011-09-19 11:56 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-17 19:59 [Qemu-devel] [PATCH 0/8] tcg/interpreter: Add TCG + interpreter for bytecode (virtual machine) Stefan Weil
2011-09-17 20:00 ` [Qemu-devel] [PATCH 1/8] tcg: Declare TCG_TARGET_REG_BITS in tcg.h Stefan Weil
2011-09-17 20:00 ` [Qemu-devel] [PATCH 2/8] tcg: Don't declare TCG_TARGET_REG_BITS in tcg-target.h Stefan Weil
2011-09-17 20:00 ` [Qemu-devel] [PATCH 3/8] tcg: Add forward declarations for local functions Stefan Weil
2011-09-17 21:40 ` Peter Maydell
2011-09-17 20:00 ` [Qemu-devel] [PATCH 4/8] tcg: Add some assertions Stefan Weil
2011-09-17 20:00 ` [Qemu-devel] [PATCH 5/8] tcg: Add interpreter for bytecode Stefan Weil
2011-09-18 4:03 ` Andi Kleen
2011-09-18 5:49 ` Stefan Weil
2011-09-18 7:22 ` Paolo Bonzini
2011-09-18 17:54 ` Avi Kivity
2011-09-19 6:52 ` Andi Kleen
2011-09-19 11:56 ` Avi Kivity [this message]
2011-09-19 14:48 ` Andi Kleen
2011-09-18 10:18 ` Blue Swirl
2011-09-19 16:43 ` Richard Henderson
2011-09-19 20:24 ` Stuart Brady
2011-10-16 21:54 ` Stuart Brady
2011-09-17 20:00 ` [Qemu-devel] [PATCH 6/8] tcg: Add bytecode generator for tcg interpreter Stefan Weil
2011-09-18 10:03 ` Blue Swirl
2011-09-19 22:28 ` Stuart Brady
2011-10-01 16:54 ` Andreas Färber
2011-10-01 21:25 ` Stefan Weil
2011-10-09 16:19 ` Andreas Färber
2011-09-17 20:00 ` [Qemu-devel] [PATCH 7/8] tcg: Add tcg interpreter to configure / make Stefan Weil
2011-09-18 9:37 ` Blue Swirl
2011-09-18 10:14 ` Stefan Weil
2011-09-17 20:00 ` [Qemu-devel] [PATCH 8/8] ppc: Support tcg interpreter on ppc hosts Stefan Weil
2011-09-17 21:31 ` Peter Maydell
2011-09-17 21:33 ` Stefan Weil
2011-09-18 10:26 ` [Qemu-devel] [PATCH 0/8] tcg/interpreter: Add TCG + interpreter for bytecode (virtual machine) Blue Swirl
2011-09-18 10:49 ` malc
2011-09-18 12:12 ` Blue Swirl
2011-09-18 12:46 ` malc
2011-09-18 13:00 ` Blue Swirl
2011-09-18 13:13 ` malc
2011-09-18 13:26 ` Blue Swirl
2011-09-25 20:37 ` Stefan Weil
2011-10-01 12:02 ` Blue Swirl
2011-09-18 15:02 ` Mulyadi Santosa
2011-09-18 15:13 ` Stefan Weil
2011-09-18 16:39 ` Mulyadi Santosa
2011-09-18 20:15 ` Stefan Weil
2011-09-19 15:14 ` Mulyadi Santosa
2011-09-19 8:40 ` David Gilbert
2011-09-19 10:20 ` Stefan Hajnoczi
2011-09-19 10:27 ` David Gilbert
2011-09-18 18:02 ` Avi Kivity
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