This is the mail archive of the binutils@sourceware.org mailing list for the binutils project.

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]
Other format:	[Raw text]

Re: [PATCH/AArch64 3/3] * opcodes/aarch64-tbl.h (aarch64_opcode_table): Add back the "lost" instruction aliases for scalar compare and vector compare.

From: Yufeng Zhang <Yufeng dot Zhang at arm dot com>
To: "Dr. Philipp Tomsich" <philipp dot tomsich at theobroma-systems dot com>
Cc: James Greenhalgh <James dot Greenhalgh at arm dot com>, Marcus Shawcroft <marcus dot shawcroft at gmail dot com>, "binutils at sourceware dot org" <binutils at sourceware dot org>
Date: Tue, 07 Jan 2014 11:08:40 +0000
Subject: Re: [PATCH/AArch64 3/3] * opcodes/aarch64-tbl.h (aarch64_opcode_table): Add back the "lost" instruction aliases for scalar compare and vector compare.
Authentication-results: sourceware.org; auth=none
References: <1386181767-10323-1-git-send-email-philipp dot tomsich at theobroma-systems dot com> <1386181767-10323-3-git-send-email-philipp dot tomsich at theobroma-systems dot com> <CAFqB+Pw=_LLrOFWPS+MnGsA094OVh_udbyhFJXNO=JOafnpNWg at mail dot gmail dot com> <A691769C-9DA2-49B9-9278-6D51B505A194 at theobroma-systems dot com> <20131211093830 dot GA2589 at arm dot com> <A9D5B571-DDA9-4A6C-9383-963B050C06E8 at theobroma-systems dot com>

Hi Philipp,

On 12/11/13 14:38, Dr. Philipp Tomsich wrote:

James,

thanks for the clarification and pointing out the change in iterators.md, which only
applies to 4.9 (I didn’t check the sources carefully enough last night), but seems to
have never made it into the 4.8.2 tree.

On 11 Dec 2013, at 10:38 , James Greenhalgh<james.greenhalgh@arm.com>  wrote:

In fact, we have this explicit comment in aarch64/iterators.md calling
out the absence of the FCMLE and FCMLT 3 register variants and
describing the workaround.

;; For comparison operators we use the FCM* and CM* instructions.
;; As there are no CMLE or CMLT instructions which act on 3 vector
;; operands, we must use CMGE or CMGT and swap the order of the
;; source operands.

If you are seeing other instructions generated it is either a bug,
or some other pattern.


I just rechecked against a fresh checkout of 4.8.2 and still don't see the n_optab
iterator there, so it appears as if that change didn’t make it onto the 4.8 tree.

In case you haven't been aware, James has backported the change togcc-4_8-branch@206133 before Christmas:


commit 0ae4ef5a14e5a50fa125142726bc6aa5fc0a05a8
Author: jgreenhalgh <jgreenhalgh@138bc75d-0d04-0410-961f-82ee72b054a4>
Date:   Thu Dec 19 20:01:26 2013 +0000

    [AArch64 4.8-branch] Backport: Fix <F>CM instruction generation.


Thanks,
Yufeng

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]