DPDK patches and discussions
 help / color / mirror / Atom feed
From: Stephen Hemminger <stephen@networkplumber.org>
To: Pavan Nikhilesh <pbhagavatula@caviumnetworks.com>
Cc: dev@dpdk.org, cristian.dumitrescu@intel.com
Subject: Re: [dpdk-dev] [PATCH 2/2] eal: add u64 bit variant for reciprocal
Date: Tue, 29 Aug 2017 12:38:00 -0700	[thread overview]
Message-ID: <20170829123800.066ee293@xeon-e3> (raw)
In-Reply-To: <1504032378-5483-2-git-send-email-pbhagavatula@caviumnetworks.com>

On Wed, 30 Aug 2017 00:16:18 +0530
Pavan Nikhilesh <pbhagavatula@caviumnetworks.com> wrote:

> +static inline uint64_t
> +mullhi_u64(uint64_t x, uint64_t y)
>  {
> -	uint32_t t = (uint32_t)(((uint64_t)a * R.m) >> 32);
> +	__uint128_t xl = x;
> +	__uint128_t yl = y;
> +	__uint128_t rl = xl * yl;
> +	return (uint64_t)(rl >> 64);
> +}

Cast in return not necessary. And cast when setting t not necessary.
Please blank line after declarations.

Also you don't need to cast both sides of multiply. Some compilers maybe
able to optimize 128 bit * 64 bit.

  parent reply	other threads:[~2017-08-29 19:38 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-29 18:46 [dpdk-dev] [PATCH 1/2] eal: introduce integer divide through reciprocal Pavan Nikhilesh
2017-08-29 18:46 ` [dpdk-dev] [PATCH 2/2] eal: add u64 bit variant for reciprocal Pavan Nikhilesh
2017-08-29 19:35   ` Stephen Hemminger
2017-08-29 19:38   ` Stephen Hemminger [this message]
2017-08-30  4:05     ` Pavan Nikhilesh Bhagavatula
2017-12-04 13:22 ` [dpdk-dev] [PATCH v7 1/3] eal: introduce integer divide through reciprocal Pavan Nikhilesh
2017-12-04 13:22   ` [dpdk-dev] [PATCH v7 2/3] eal: add u64 bit variant for reciprocal Pavan Nikhilesh
2017-12-04 13:22   ` [dpdk-dev] [PATCH v7 3/3] test: add tests for reciprocal based division Pavan Nikhilesh
2018-01-18 23:49     ` Thomas Monjalon
2018-01-25 22:35       ` Thomas Monjalon
2018-01-11 16:01   ` [dpdk-dev] [PATCH v7 1/3] eal: introduce integer divide through reciprocal Dumitrescu, Cristian
2018-01-26  5:04 ` [dpdk-dev] [PATCH v8 " Pavan Nikhilesh
2018-01-26  5:04   ` [dpdk-dev] [PATCH v8 2/3] eal: add u64 bit variant for reciprocal Pavan Nikhilesh
2018-01-29  6:42     ` Hemant Agrawal
2018-01-29  7:54       ` Pavan Nikhilesh
2018-01-29  8:14         ` Hemant Agrawal
2018-10-28  0:06     ` Ferruh Yigit
2018-01-26  5:04   ` [dpdk-dev] [PATCH v8 3/3] test: add tests for reciprocal based division Pavan Nikhilesh
2018-01-27 21:39   ` [dpdk-dev] [PATCH v8 1/3] eal: introduce integer divide through reciprocal Thomas Monjalon

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20170829123800.066ee293@xeon-e3 \
    --to=stephen@networkplumber.org \
    --cc=cristian.dumitrescu@intel.com \
    --cc=dev@dpdk.org \
    --cc=pbhagavatula@caviumnetworks.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).