> > Sounds good. I'll get those setup and running and will report back on > > findings. What's the preferred way to measure codesize? I'm assuming > > by default the code pages are aligned so smaller differences would need to > > trip > over the boundary to actually show up. > > You can use the size command on the binaries: > > >size /bin/ls > text data bss dec hex filename > 107271 2024 3472 112767 1b87f /bin/ls > > As you can see it shows the text size in bytes. It is not rounded up to a > page, so it > is an accurate measure of the codesize. Generally -O2 size is most useful to > check (since that is what most applications build with), but -Ofast -flto can > be > useful as well (the global inlining means you get instruction combinations > which > appear less often with -O2). > > Cheers, > Wilco Alrighty, I've got spec 2017 and spec 2006 setup and building. Using default configurations so -O2 in spec2006 and -O3 in spec2017. Testing the patch as last sent showed a 1% code size regression in spec 2017 perlbench which turned out to be a missing pattern for tbnz and all its variants:
(define_insn "*tb<optab><mode>1"
[(set (pc) (if_then_else
(EQL (zero_extract:DI (match_operand:GPI 0 "register_operand"
"r") <--- only matches against zero_extract:DI
(const_int 1)
(match_operand 1
"aarch64_simd_shift_imm_<mode>" "n"))
The zero extract now matching against other modes would generate a test +
branch rather than the combined instruction which led to the code size
regression. I've updated the patch so that tbnz etc. matches GPI and that
brings code size down to <0.2% in spec2017 and <0.4% in spec2006.
Spec results are attached for reference.
@Wilco I've gotten instruction on my side to set up an individual contributor's
license for the time being. Can you send me the necessary documents to make
that happen? Thanks!
ChangeLog:
2020-02-21 Di Mo <mod...@microsoft.com>
gcc/
* config/aarch64/aarch64.md: Add GPI modes to extsv/extv patterns.
Allow tb<optab><mode>1 pattern to match against zero_extract:GPI.
* expmed.c (extract_bit_field_using_extv): Change gen_lowpart to
gen_lowpart_if_possible to avoid compiler assert building libgcc.
testsuite/
* gcc.target/aarch64/pr86901.c: Add new test.
Modi
pr86901.patch
Description: pr86901.patch
spec2006
Description: spec2006
spec2017
Description: spec2017
