>>> So back to the original task for you: Show me in the generated output where the benefits are.
I can offer another bit of information for this software development discussion.
The following build settings were active in my "Makefile" for this Linux test case.
…
HOSTCFLAGS = -Wall -Wmissing-prototypes -Wstrict-prototypes -O0 -fomit-frame-pointer -std=gnu89
…
The afffected source files can be compiled for the processor architecture "x86_64"
by a tool like "GCC 6.2.1+r239849-1.5" from the software distribution
"openSUSE Tumbleweed" with the following command example.
my_original=${my_build_dir}unchanged/test/ \
&& my_fixing=${my_build_dir}patched/test/ \
&& mkdir -p ${my_original} ${my_fixing} \
&& my_cc=/usr/bin/gcc-6 \
&& my_module=drivers/md/raid1.s \
&& git checkout next-20161014 \
&& make -j6 O="${my_original}" CC="${my_cc}" HOSTCC="${my_cc}" allmodconfig "${my_module}" \
&& git checkout next_usage_of_seq_putc_in_md_raid_1 \
&& make -j6 O="${my_fixing}" CC="${my_cc}" HOSTCC="${my_cc}" allmodconfig "${my_module}" \
&& diff -u "${my_original}${my_module}" "${my_fixing}${my_module}" > "${my_build_dir}assembler_code_comparison_$(date -I)_3.diff"
The generated file got the size "25.4 KiB" this time. I guess that only
the following two diff hunks are interesting then to show desired effects
for the suggested software refactoring around data output of a single character
(instead of a similar string).
…
@@ -4402,10 +4402,6 @@
.LC19:
.string "%s"
.zero 61
- .align 32
-.LC20:
- .string "]"
- .zero 62
.text
.p2align 4,,15
.type raid1_status, @function
@@ -4564,8 +4560,8 @@
movq $rcu_lock_map, %rdi #,
call lock_release #
movq %r14, %rdi # seq,
- movq $.LC20, %rsi #,
- call seq_printf #
+ movl $93, %esi #,
+ call seq_putc #
addq $16, %rsp #,
popq %rbx #
popq %r12 #
…
* Is this kind of assembler code comparison useful to clarify relevant
differences further?
* Are any software development concerns left over for such a transformation?
Regards,
Markus
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