[Bug tree-optimization/106322] [12/13 Regression] tree-vectorize: Wrong code at O2 level (-fno-tree-vectorize is working) since r12-2404-ga1d27560770818c5

["malat at debian dot org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106322

--- Comment #35 from Mathieu Malaterre <malat at debian dot org> ---
(In reply to Mathieu Malaterre from comment #33)
> (In reply to Kewen Lin from comment #32)
> > (In reply to Mathieu Malaterre from comment #30)
> > > (In reply to Martin Liška from comment #29)
> > > > (In reply to Kewen Lin from comment #28)
> > > > > Sorry for the breakage, I'll have a look tomorrow.
> > > > > 
> > > > > btw, is it able to reproduce the issue on ppc64 (or ppc64le) as well?
> > > > 
> > > > No for gcc112 machine (ppc64le). Seems to be related to 32-bit targets.
> > > 
> > > I could see unit-test failures of highway on most 32bits arch, as well as
> > > mips64el and ppc64be.
> > 
> > Thanks to both guys! I'll try with ppc64 32bit first.
> 
> Watch out that I've reduced the original test case on my local x86/32bits
> arch.
> 
> It appears that I've lifted way too much code to reproduce the issue on
> ppc32/be. Is is ok for you to use instead, reproducer from previous comment:
> 
> * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106322#c16

Nevermind; I was using gcc-11.

I can reproduce the issue on ppc32/be using the (somewhat) reduced example:

* https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106322#c19

For reference:

% g++ -O2 -fno-tree-vectorize *.cc && ./a.out && echo "ok"
ok

But:

% g++ --verbose -O2 *.cc && ./a.out && echo "ok"
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/powerpc-linux-gnu/12/lto-wrapper
Target: powerpc-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Debian 12.1.0-7'
--with-bugurl=file:///usr/share/doc/gcc-12/README.Bugs
--enable-languages=c,ada,c++,go,d,fortran,objc,obj-c++ --prefix=/usr
--with-gcc-major-version-only --program-suffix=-12
--program-prefix=powerpc-linux-gnu- --enable-shared --enable-linker-build-id
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--libdir=/usr/lib --enable-nls --enable-clocale=gnu --enable-libstdcxx-debug
--enable-libstdcxx-time=yes --with-default-libstdcxx-abi=new
--enable-gnu-unique-object --disable-libitm --disable-libquadmath
--disable-libquadmath-support --enable-plugin --enable-default-pie
--with-system-zlib --enable-libphobos-checking=release
--with-target-system-zlib=auto --with-libphobos-druntime-only=yes
--enable-objc-gc=auto --enable-secureplt --disable-softfloat
--with-cpu=default32 --disable-softfloat
--enable-targets=powerpc-linux,powerpc64-linux --enable-multiarch
--disable-werror --with-long-double-128 --enable-multilib
--enable-checking=release --build=powerpc-linux-gnu --host=powerpc-linux-gnu
--target=powerpc-linux-gnu
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 12.1.0 (Debian 12.1.0-7)
COLLECT_GCC_OPTIONS='-v' '-O2' '-shared-libgcc' '-dumpdir' 'a-'
 /usr/lib/gcc/powerpc-linux-gnu/12/cc1plus -quiet -v -imultiarch
powerpc-linux-gnu -D_GNU_SOURCE bytes.cc -msecure-plt -quiet -dumpdir a-
-dumpbase bytes.cc -dumpbase-ext .cc -O2 -version -o /tmp/ccXa9nGd.s
GNU C++17 (Debian 12.1.0-7) version 12.1.0 (powerpc-linux-gnu)
        compiled by GNU C version 12.1.0, GMP version 6.2.1, MPFR version
4.1.0, MPC version 1.2.1, isl version isl-0.25-GMP

GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
ignoring duplicate directory "/usr/include/powerpc-linux-gnu/c++/12"
ignoring nonexistent directory "/usr/local/include/powerpc-linux-gnu"
ignoring nonexistent directory
"/usr/lib/gcc/powerpc-linux-gnu/12/include-fixed"
ignoring nonexistent directory
"/usr/lib/gcc/powerpc-linux-gnu/12/../../../../powerpc-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/include/c++/12
 /usr/include/powerpc-linux-gnu/c++/12
 /usr/include/c++/12/backward
 /usr/lib/gcc/powerpc-linux-gnu/12/include
 /usr/local/include
 /usr/include/powerpc-linux-gnu
 /usr/include
End of search list.
GNU C++17 (Debian 12.1.0-7) version 12.1.0 (powerpc-linux-gnu)
        compiled by GNU C version 12.1.0, GMP version 6.2.1, MPFR version
4.1.0, MPC version 1.2.1, isl version isl-0.25-GMP

GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 56cdbc606649bdc6108da73e5dd1af6f
COLLECT_GCC_OPTIONS='-v' '-O2' '-shared-libgcc' '-dumpdir' 'a-'
 as -v -a32 -K PIC -mppc -many -mbig -o /tmp/ccKx6rlb.o /tmp/ccXa9nGd.s
GNU assembler version 2.38.90 (powerpc-linux-gnu) using BFD version (GNU
Binutils for Debian) 2.38.90.20220713
COLLECT_GCC_OPTIONS='-v' '-O2' '-shared-libgcc' '-dumpdir' 'a-'
 /usr/lib/gcc/powerpc-linux-gnu/12/cc1plus -quiet -v -imultiarch
powerpc-linux-gnu -D_GNU_SOURCE demo.cc -msecure-plt -quiet -dumpdir a-
-dumpbase demo.cc -dumpbase-ext .cc -O2 -version -o /tmp/ccXa9nGd.s
GNU C++17 (Debian 12.1.0-7) version 12.1.0 (powerpc-linux-gnu)
        compiled by GNU C version 12.1.0, GMP version 6.2.1, MPFR version
4.1.0, MPC version 1.2.1, isl version isl-0.25-GMP

GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
ignoring duplicate directory "/usr/include/powerpc-linux-gnu/c++/12"
ignoring nonexistent directory "/usr/local/include/powerpc-linux-gnu"
ignoring nonexistent directory
"/usr/lib/gcc/powerpc-linux-gnu/12/include-fixed"
ignoring nonexistent directory
"/usr/lib/gcc/powerpc-linux-gnu/12/../../../../powerpc-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/include/c++/12
 /usr/include/powerpc-linux-gnu/c++/12
 /usr/include/c++/12/backward
 /usr/lib/gcc/powerpc-linux-gnu/12/include
 /usr/local/include
 /usr/include/powerpc-linux-gnu
 /usr/include
End of search list.
GNU C++17 (Debian 12.1.0-7) version 12.1.0 (powerpc-linux-gnu)
        compiled by GNU C version 12.1.0, GMP version 6.2.1, MPFR version
4.1.0, MPC version 1.2.1, isl version isl-0.25-GMP

GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 56cdbc606649bdc6108da73e5dd1af6f
COLLECT_GCC_OPTIONS='-v' '-O2' '-shared-libgcc' '-dumpdir' 'a-'
 as -v -a32 -K PIC -mppc -many -mbig -o /tmp/ccTxltFy.o /tmp/ccXa9nGd.s
GNU assembler version 2.38.90 (powerpc-linux-gnu) using BFD version (GNU
Binutils for Debian) 2.38.90.20220713
COMPILER_PATH=/usr/lib/gcc/powerpc-linux-gnu/12/:/usr/lib/gcc/powerpc-linux-gnu/12/:/usr/lib/gcc/powerpc-linux-gnu/:/usr/lib/gcc/powerpc-linux-gnu/12/:/usr/lib/gcc/powerpc-linux-gnu/
LIBRARY_PATH=/usr/lib/gcc/powerpc-linux-gnu/12/:/usr/lib/gcc/powerpc-linux-gnu/12/../../../powerpc-linux-gnu/:/usr/lib/gcc/powerpc-linux-gnu/12/../../../../lib/:/lib/powerpc-linux-gnu/:/lib/../lib/:/usr/lib/powerpc-linux-gnu/:/usr/lib/../lib/:/usr/lib/gcc/powerpc-linux-gnu/12/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-v' '-O2' '-shared-libgcc' '-dumpdir' 'a.'
 /usr/lib/gcc/powerpc-linux-gnu/12/collect2 -plugin
/usr/lib/gcc/powerpc-linux-gnu/12/liblto_plugin.so
-plugin-opt=/usr/lib/gcc/powerpc-linux-gnu/12/lto-wrapper
-plugin-opt=-fresolution=/tmp/ccfJV0ms.res -plugin-opt=-pass-through=-lgcc_s
-plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lc
-plugin-opt=-pass-through=-lgcc_s -plugin-opt=-pass-through=-lgcc --build-id
--eh-frame-hdr -V --secure-plt -m elf32ppclinux --hash-style=gnu --as-needed
-dynamic-linker /lib/ld.so.1 -pie
/usr/lib/gcc/powerpc-linux-gnu/12/../../../powerpc-linux-gnu/Scrt1.o
/usr/lib/gcc/powerpc-linux-gnu/12/../../../powerpc-linux-gnu/crti.o
/usr/lib/gcc/powerpc-linux-gnu/12/crtbeginS.o
-L/usr/lib/gcc/powerpc-linux-gnu/12
-L/usr/lib/gcc/powerpc-linux-gnu/12/../../../powerpc-linux-gnu
-L/usr/lib/gcc/powerpc-linux-gnu/12/../../../../lib -L/lib/powerpc-linux-gnu
-L/lib/../lib -L/usr/lib/powerpc-linux-gnu -L/usr/lib/../lib
-L/usr/lib/gcc/powerpc-linux-gnu/12/../../.. /tmp/ccKx6rlb.o /tmp/ccTxltFy.o
-lstdc++ -lm -lgcc_s -lgcc -lc -lgcc_s -lgcc
/usr/lib/gcc/powerpc-linux-gnu/12/crtendS.o
/usr/lib/gcc/powerpc-linux-gnu/12/../../../powerpc-linux-gnu/crtn.o
GNU ld (GNU Binutils for Debian) 2.38.90.20220713
  Supported emulations:
   elf32ppclinux
   elf32ppc
   elf32ppcsim
   elf32lppclinux
   elf32lppc
   elf32lppcsim
   elf64ppc
   elf64lppc
COLLECT_GCC_OPTIONS='-v' '-O2' '-shared-libgcc' '-dumpdir' 'a.'
zsh: IOT instruction  ./a.out