mips: optimize mips32_pracc_write_regs() code. 57/957/3
authorSalvador Arroyo <sarroyofdez@yahoo.es>
Sat, 3 Nov 2012 10:29:46 +0000 (11:29 +0100)
committerSpencer Oliver <spen@spen-soft.co.uk>
Fri, 16 Nov 2012 12:42:03 +0000 (12:42 +0000)
commit18077654afaa6f5325abf0d01187161770ff8ce4
treeaa4043f45ad974d210161d1eed4039662e7d0a6c
parentf3e01106d9a8e7ad6b81413f37c1f6d5c806600d
mips: optimize mips32_pracc_write_regs() code.

All the the loads are done with lui and ori instructions, there is
no need to save any register, they will be overwritten.
Like in the previous patch, for speed optimization in write code,
same instructions can be saved if the lower half word or the upper
half word is 0.
If the lower half word is 0, it can be loaded with only a lui instruction.
If the higher half word is 0 it can be done with an ori instruction with register 0.
This code saves 10 pracc accesses at a minimum, and 40 at a maximum,
obviously if register 2 to 31 are 0 or a half word is 0
Current code needs 91 pracc accesses.

Change-Id: I892c5b440191d0c7a474c96845d41c373b7fc637
Signed-off-by: Salvador Arroyo <sarroyofdez@yahoo.es>
Reviewed-on: http://openocd.zylin.com/957
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>
Tested-by: jenkins
src/target/mips32_pracc.c

Linking to existing account procedure

If you already have an account and want to add another login method you MUST first sign in with your existing account and then change URL to read https://review.openocd.org/login/?link to get to this page again but this time it'll work for linking. Thank you.

SSH host keys fingerprints

1024 SHA256:YKx8b7u5ZWdcbp7/4AeXNaqElP49m6QrwfXaqQGJAOk gerrit-code-review@openocd.zylin.com (DSA)
384 SHA256:jHIbSQa4REvwCFG4cq5LBlBLxmxSqelQPem/EXIrxjk gerrit-code-review@openocd.org (ECDSA)
521 SHA256:UAOPYkU9Fjtcao0Ul/Rrlnj/OsQvt+pgdYSZ4jOYdgs gerrit-code-review@openocd.org (ECDSA)
256 SHA256:A13M5QlnozFOvTllybRZH6vm7iSt0XLxbA48yfc2yfY gerrit-code-review@openocd.org (ECDSA)
256 SHA256:spYMBqEYoAOtK7yZBrcwE8ZpYt6b68Cfh9yEVetvbXg gerrit-code-review@openocd.org (ED25519)
+--[ED25519 256]--+
|=..              |
|+o..   .         |
|*.o   . .        |
|+B . . .         |
|Bo. = o S        |
|Oo.+ + =         |
|oB=.* = . o      |
| =+=.+   + E     |
|. .=o   . o      |
+----[SHA256]-----+
2048 SHA256:0Onrb7/PHjpo6iVZ7xQX2riKN83FJ3KGU0TvI0TaFG4 gerrit-code-review@openocd.zylin.com (RSA)