https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124138
Bug ID: 124138
Summary: [16 Regression] wrong code with -mavx512f and
__builtin_shufflevector() / vpermilpd
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Keywords: wrong-code
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: zsojka at seznam dot cz
Target Milestone: ---
Host: x86_64-pc-linux-gnu
Target: x86_64-pc-linux-gnu
Created attachment 63696
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=63696&action=edit
reduced testcase
Output:
$ x86_64-pc-linux-gnu-gcc testcase.c -mavx512f
$ sde64 -future -- ./a.out || echo FAIL
FAIL
vmovdqa64 ZMMWORD PTR [rsp-56], zmm0 # u, u
vmovdqa64 ZMMWORD PTR [rsp-120], zmm1 # v, v
vmovdqa64 zmm0, ZMMWORD PTR [rsp-120] # tmp102, v
vpermilpd zmm0, zmm0, 186 # _1, tmp102,
it seems the permutation is using only the vector 'v'
$ x86_64-pc-linux-gnu-gcc -v
Using built-in specs.
COLLECT_GCC=/repo/gcc-trunk/binary-latest-amd64/bin/x86_64-pc-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-20260216182635-r16-7532-g716ec14c573c7e-checking-yes-rtl-df-extra-nobootstrap-amd64/bin/../libexec/gcc/x86_64-pc-linux-gnu/16.0.1/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /repo/gcc-trunk//configure --enable-languages=c,c++
--enable-valgrind-annotations --disable-nls --enable-checking=yes,rtl,df,extra
--disable-bootstrap --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu
--target=x86_64-pc-linux-gnu --with-ld=/usr/bin/x86_64-pc-linux-gnu-ld
--with-as=/usr/bin/x86_64-pc-linux-gnu-as --enable-libsanitizer
--disable-libstdcxx-pch
--prefix=/repo/gcc-trunk//binary-trunk-20260216182635-r16-7532-g716ec14c573c7e-checking-yes-rtl-df-extra-nobootstrap-amd64
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 16.0.1 20260216 (experimental) (GCC)
