Package: libjpeg62-turbo
Version: 1:1.5.2-2+b1
Severity: normal
Tags: patch upstream
Hi,
When profiling any program that uses libjpeg-turbo, there's a proliferation
of “symbols” that are really internal labels, confusing the profiler:
14,50% MJPEG_Encode libjpeg.so.62.2.0 [.]
jsimd_fdct_islow_sse2
8,80% MJPEG_Encode nageru [.]
memcpy_interleaved_fastpath
8,69% MJPEG_Encode libjpeg.so.62.2.0 [.]
..@25..CHECKBUF47_END
4,51% MJPEG_Encode libc-2.28.so [.]
__memmove_avx_unaligned_erms
3,81% MJPEG_Encode libjpeg.so.62.2.0 [.]
jsimd_quantize_sse2.quantloop
3,24% MJPEG_Encode libjpeg.so.62.2.0 [.] encode_mcu_huff
2,81% Mixer_Audio libzita-resampler.so.1.6.0 [.] Resampler::process
2,54% MJPEG_Encode libjpeg.so.62.2.0 [.]
jsimd_convsamp_sse2.convloop
2,44% nageru [unknown] [k] 0xffffffffa280015f
2,31% MHD-connection [unknown] [k] 0xffffffffa280015f
2,09% MJPEG_Encode libjpeg.so.62.2.0 [.]
..@44..CHECKBUF31_END
2,02% QS_Encode [unknown] [k] 0xffffffffa280015f
1,98% Mixer_Audio libzita-resampler.so.1.6.0 [.]
VResampler::process
1,89% MJPEG_Encode libjpeg.so.62.2.0 [.] compress_data
1,57% MJPEG_Encode libjpeg.so.62.2.0 [.]
jsimd_huff_encode_one_block_sse2.BLOOP
1,39% MJPEG_Encode libjpeg.so.62.2.0 [.] forward_DCT
1,21% MJPEG_Encode libjpeg.so.62.2.0 [.]
jsimd_huff_encode_one_block_sse2
Note in particular ..@25..CHECKBUF47_END, which is really part of
jsimd_huff_encode_one_block_sse2, and the same with .BLOOP. This is a known
shortcoming of nasm, but can be stripped out fairly easily, e.g., with
something like
--- libjpeg-turbo-1.5.2.orig/simd/nasm_lt.sh
+++ libjpeg-turbo-1.5.2/simd/nasm_lt.sh
@@ -39,6 +39,7 @@ while [ $# -gt 0 ]; do
-o*)
o_opt=yes
command="$command $1"
+ outfile="$2"
;;
*.asm)
infile=$1
@@ -53,8 +54,11 @@ done
if [ "$o_opt" != yes ] ; then
# By default, NASM creates an output file
# in the same directory as the input file.
- outfile="-o `echo $infile | sed -e 's%^.*/%%' -e 's%\.[^.]*$%%'`.o"
- command="$command $outfile"
+ outfile="`echo $infile | sed -e 's%^.*/%%' -e 's%\.[^.]*$%%'`.o"
+ command="$command -o $outfile"
fi
+set -e
echo $command
-exec $command
+$command
+echo strip --discard-locals --wildcard --strip-symbol='?*.*' $outfile
+strip --discard-locals --wildcard --strip-symbol='?*.*' $outfile
After applying said patch and rebuilding, the profile is a lot more readable
and less cluttered:
16,05% MJPEG_Encode libjpeg.so.62.2.0 [.]
jsimd_huff_encode_one_block_sse2
14,38% MJPEG_Encode libjpeg.so.62.2.0 [.]
jsimd_fdct_islow_sse2
8,50% MJPEG_Encode nageru [.]
memcpy_interleaved_fastpath
4,75% MJPEG_Encode libjpeg.so.62.2.0 [.]
jsimd_quantize_sse2
3,71% MJPEG_Encode libc-2.28.so [.]
__memmove_avx_unaligned_erms
3,11% MJPEG_Encode libjpeg.so.62.2.0 [.]
jsimd_convsamp_sse2
2,86% MJPEG_Encode libjpeg.so.62.2.0 [.] encode_mcu_huff
Backtracing and disassembling in gdb is also affected by this issue.
-- System Information:
Debian Release: buster/sid
APT prefers testing-debug
APT policy: (500, 'testing-debug'), (500, 'testing'), (500, 'stable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386
Kernel: Linux 4.19.11 (SMP w/40 CPU cores)
Locale: LANG=en_DK.UTF-8, LC_CTYPE=en_DK.UTF-8 (charmap=UTF-8),
LANGUAGE=en_NO:en_US:en_GB:en (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
Versions of packages libjpeg62-turbo depends on:
ii libc6 2.28-2
libjpeg62-turbo recommends no packages.
libjpeg62-turbo suggests no packages.
-- debconf-show failed
