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From: John David Anglin <dave.anglin@bell.net>
To: Jeff Law <jeffreyalaw@gmail.com>, Sam James <sam@gentoo.org>
Cc: John David Anglin <dave@parisc-linux.org>,
	GCC Patches <gcc-patches@gcc.gnu.org>
Subject: Re: [committed] hppa: Revise REG+D address support to allow long displacements before reload
Date: Fri, 17 Nov 2023 03:27:03 -0500	[thread overview]
Message-ID: <2c6d8866-66f1-49b8-858d-05c8fcb34486@bell.net> (raw)
In-Reply-To: <4d8dae42-cfe9-42a7-8c4d-1f1cbb82370f@gmail.com>

On 2023-11-16 10:00 p.m., Jeff Law wrote:
>>> I'm not seeing any obvious problems in the gcc testsuite.  It needs testing on packages that do extensive
>>> floating point calculations.
>>
>> OK, I'll focus on those.
> THe more likely scenario is xmpy which is used for integer multiply, but the operands have to be moved into FP registers because the operation 
> happens in the FPU.
There are lots of xmpyu instructions in cc1 and cc1plus.  For example,

   9fee8c:       08 03 02 5c     copy r3,ret0
   9fee90:       37 9c 00 20     ldo 10(ret0),ret0
   9fee94:       27 80 10 17     fldw 0(ret0),fr23
   9fee98:       08 03 02 5c     copy r3,ret0
   9fee9c:       37 9c 00 28     ldo 14(ret0),ret0
   9feea0:       27 80 10 16     fldw 0(ret0),fr22
   9feea4:       3a f6 47 18     xmpyu fr23,fr22,fr24
   9feea8:       2f c1 12 18     fstd fr24,-10(sp)
   9feeac:       0f c1 10 9c     ldw -10(sp),ret0
   9feeb0:       0f c9 10 9d     ldw -c(sp),ret1

There are 2169 xmpyu instructions in cc1plus in my current gcc bootstrap on linux.

Dave

-- 
John David Anglin  dave.anglin@bell.net


  reply	other threads:[~2023-11-17  8:27 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-11-16 17:54 John David Anglin
2023-11-16 21:52 ` Jeff Law
2023-11-16 22:33   ` John David Anglin
2023-11-17  1:20     ` Sam James
2023-11-17  1:25       ` Sam James
2023-11-17  3:00       ` Jeff Law
2023-11-17  8:27         ` John David Anglin [this message]
2023-11-17 14:14           ` Jeff Law

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