xemu/scripts/coccinelle/tcg_gen_extract.cocci
Mao Zhongyi e8d81a61e1 qemu-iotests: convert pwd and $(pwd) to $PWD
POSIX requires $PWD to be reliable, and we expect all
shells used by qemu scripts to be relatively close to
POSIX.  Thus, it is smarter to avoid forking the pwd
executable for something that is already available in
the environment.

So replace it with the following:

sed -i 's/\(`pwd`\|\$(pwd)\)/$PWD/g' $(git grep -l pwd)

Then delete a pointless line assigning PWD to itself.

Cc: kwolf@redhat.com
Cc: mreitz@redhat.com
Cc: eblake@redhat.com
Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Mao Zhongyi <maozhongyi@cmss.chinamobile.com>
Message-Id: <20181024094051.4470-2-maozhongyi@cmss.chinamobile.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: touch up commit message, reorder series, tweak a couple more files]
Signed-off-by: Eric Blake <eblake@redhat.com>
2018-11-19 10:08:19 -06:00

108 lines
2.9 KiB
Plaintext

// optimize TCG using extract op
//
// Copyright: (C) 2017 Philippe Mathieu-Daudé. GPLv2+.
// Confidence: High
// Options: --macro-file scripts/cocci-macro-file.h
//
// Nikunj A Dadhania optimization:
// http://lists.nongnu.org/archive/html/qemu-devel/2017-02/msg05211.html
// Aurelien Jarno optimization:
// http://lists.nongnu.org/archive/html/qemu-devel/2017-05/msg01466.html
//
// This script can be run either using spatch locally or via a docker image:
//
// $ spatch \
// --macro-file scripts/cocci-macro-file.h \
// --sp-file scripts/coccinelle/tcg_gen_extract.cocci \
// --keep-comments --in-place \
// --use-gitgrep --dir target
//
// $ docker run --rm -v $PWD:$PWD -w $PWD philmd/coccinelle \
// --macro-file scripts/cocci-macro-file.h \
// --sp-file scripts/coccinelle/tcg_gen_extract.cocci \
// --keep-comments --in-place \
// --use-gitgrep --dir target
@initialize:python@
@@
import sys
fd = sys.stderr
def debug(msg="", trailer="\n"):
fd.write("[DBG] " + msg + trailer)
def low_bits_count(value):
bits_count = 0
while (value & (1 << bits_count)):
bits_count += 1
return bits_count
def Mn(order): # Mersenne number
return (1 << order) - 1
@match@
identifier ret;
metavariable arg;
constant ofs, msk;
position shr_p, and_p;
@@
(
tcg_gen_shri_i32@shr_p
|
tcg_gen_shri_i64@shr_p
|
tcg_gen_shri_tl@shr_p
)(ret, arg, ofs);
... WHEN != ret
(
tcg_gen_andi_i32@and_p
|
tcg_gen_andi_i64@and_p
|
tcg_gen_andi_tl@and_p
)(ret, ret, msk);
@script:python verify_len depends on match@
ret_s << match.ret;
msk_s << match.msk;
shr_p << match.shr_p;
extract_len;
@@
is_optimizable = False
debug("candidate at %s:%s" % (shr_p[0].file, shr_p[0].line))
try: # only eval integer, no #define like 'SR_M' (cpp did this, else some headers are missing).
msk_v = long(msk_s.strip("UL"), 0)
msk_b = low_bits_count(msk_v)
if msk_b == 0:
debug(" value: 0x%x low_bits: %d" % (msk_v, msk_b))
else:
debug(" value: 0x%x low_bits: %d [Mersenne number: 0x%x]" % (msk_v, msk_b, Mn(msk_b)))
is_optimizable = Mn(msk_b) == msk_v # check low_bits
coccinelle.extract_len = "%d" % msk_b
debug(" candidate %s optimizable" % ("IS" if is_optimizable else "is NOT"))
except:
debug(" ERROR (check included headers?)")
cocci.include_match(is_optimizable)
debug()
@replacement depends on verify_len@
identifier match.ret;
metavariable match.arg;
constant match.ofs, match.msk;
position match.shr_p, match.and_p;
identifier verify_len.extract_len;
@@
(
-tcg_gen_shri_i32@shr_p(ret, arg, ofs);
+tcg_gen_extract_i32(ret, arg, ofs, extract_len);
... WHEN != ret
-tcg_gen_andi_i32@and_p(ret, ret, msk);
|
-tcg_gen_shri_i64@shr_p(ret, arg, ofs);
+tcg_gen_extract_i64(ret, arg, ofs, extract_len);
... WHEN != ret
-tcg_gen_andi_i64@and_p(ret, ret, msk);
|
-tcg_gen_shri_tl@shr_p(ret, arg, ofs);
+tcg_gen_extract_tl(ret, arg, ofs, extract_len);
... WHEN != ret
-tcg_gen_andi_tl@and_p(ret, ret, msk);
)