From: "Michael Chapman" <michael.chapman@wanadoo.fr>
To: <cgen@sources.redhat.com>
Subject: Different length variants of the same instruction
Date: Fri, 27 Sep 2002 17:19:00 -0000 [thread overview]
Message-ID: <001901c26684$c08ce2d0$8001a8c0@wanadoo.fr> (raw)
I can't figure out how to get the assembler to work with different
lengths of the same instruction e.g.
mov r1, #imm4 (16 bit instruction for immediate values 0-15)
and
mov r1, #imm16 (32 bit instruction for immediate values 0-65535)
If I simply have the following description
(dni mov-rd-imm4 "mov rd,#imm4"
()
"mov $rd,$hash$imm4"
(+ (f-opcode #x10) rd imm4)
(set rd imm4)
()
)
(dni mov-rd-imm16 "mov rd,#imm16"
()
"mov $rd,$hash$imm16"
(+ (f-opcode #x60) rd (f-rsvd-rs 0) imm16)
(set rd imm16)
()
)
I.e. the imm4 variant before the imm16 variant then I can write
mov r1, #0x1234
to get a 32 bit instruction.
However if I try
mov r1, #(l2-l1)
where l1 and l2 are instruction labels, it always tries to assemble this
with the imm4 variant -
even if the value of the expression is too big.
Why?
I have a similiar problem with conditional branches which come in two
lengths as well.
I have experimented with RELAX and RELAXABLE with no sucess.
Can someone explain things?
Thanks,
Mike Chapman
reply other threads:[~2002-09-28 0:19 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='001901c26684$c08ce2d0$8001a8c0@wanadoo.fr' \
--to=michael.chapman@wanadoo.fr \
--cc=cgen@sources.redhat.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 read-only IMAP folder(s) and NNTP newsgroup(s).