public inbox for [email protected]
help / color / mirror / Atom feedFrom: Daniel Gustafsson <[email protected]>
To: XChy <[email protected]>
Cc: [email protected]
Subject: Re: Missed compiler optimization issue in function select_rtable_names_for_explain
Date: Wed, 22 May 2024 11:51:00 +0200
Message-ID: <[email protected]> (raw)
In-Reply-To: <OS0P286MB016392E0B2017DDB6709A11C82EB2@OS0P286MB0163.JPNP286.PROD.OUTLOOK.COM>
References: <OS0P286MB016392E0B2017DDB6709A11C82EB2@OS0P286MB0163.JPNP286.PROD.OUTLOOK.COM>
> On 22 May 2024, at 11:27, XChy <[email protected]> wrote:
>
> Hi everyone,
> I'm a compiler developer working on detecting missed optimization in real-world applications. Recently, we found that LLVM missed a dead store elimination optimization in the PostgreSQL code (https://github.com/postgres/postgres/blob/master/src/backend/utils/adt/ruleutils.c#L3794) in the master branch.
How is the memset in select_rtable_names_for_explain a dead-store? Even memset
calls could be optimized away from the EXPLAIN codepath I have a feeling it
would have to be many in a tight loop for it to be measurable even?
--
Daniel Gustafsson
reply
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: [email protected]
Cc: [email protected], [email protected]
Subject: Re: Missed compiler optimization issue in function select_rtable_names_for_explain
In-Reply-To: <[email protected]>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox