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From: "ntukanov at cmu dot edu" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug inline-asm/102264] Macro Intrinsics fail to use all the registers on the machine
Date: Fri, 10 Sep 2021 03:27:51 +0000	[thread overview]
Message-ID: <bug-102264-4-gM4s93LnQR@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-102264-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102264

--- Comment #2 from Nicholai Tukanov <ntukanov at cmu dot edu> ---
(In reply to Andrew Pinski from comment #1)
> There seems to be some extra moves the register allocator cannot remove and
> that is causing some extra spilling.
>
> Your loop has 32 live variables and that is just at the limit.

Can the register allocator be modified to recognize the other registers? The
problem seems limited to the compute instruction (vpdpwssd in this case). 

I specifically choose 32 to max out the registers. Since the compute
instruction gets limited to half of that (zmm0-zmm15), the extra moves are
killing the performance.

  parent reply	other threads:[~2021-09-10  3:27 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-09 20:43 [Bug inline-asm/102264] New: " ntukanov at cmu dot edu
2021-09-09 21:12 ` [Bug inline-asm/102264] " pinskia at gcc dot gnu.org
2021-09-10  3:27 ` ntukanov at cmu dot edu [this message]
2021-09-10  7:49 ` [Bug target/102264] " rguenth at gcc dot gnu.org
2021-09-10  8:24 ` pinskia at gcc dot gnu.org
2021-09-10  8:42 ` [Bug target/102264] [9/10/11/12 Regression] extra spilling when using inline-asm and all registers pinskia at gcc dot gnu.org
2021-09-19 23:17 ` pinskia at gcc dot gnu.org
2022-01-20 10:14 ` rguenth at gcc dot gnu.org
2022-03-23  8:42 ` rguenth at gcc dot gnu.org
2022-05-27  9:46 ` [Bug target/102264] [10/11/12/13 " rguenth at gcc dot gnu.org
2022-06-28 10:46 ` jakub at gcc dot gnu.org
2023-07-07 10:40 ` [Bug target/102264] [11/12/13/14 " rguenth at gcc dot gnu.org
2024-03-10  3:20 ` law at gcc dot gnu.org
2024-03-22 14:08 ` law at gcc dot gnu.org

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