https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101345
Bug ID: 101345 Summary: wrong code at -O1 with vector modulo Product: gcc Version: 12.0 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: powerpc64le-unknown-linux-gnu Created attachment 51110 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=51110&action=edit reduced testcase Output: $ powerpc64le-unknown-linux-gnu-gcc -O testcase.c -static $ qemu-ppc64le -- ./a.out qemu: uncaught target signal 6 (Aborted) - core dumped Aborted The value is 0x2828282828282828 instead of 0x1414141414141414 Already the computed value of "y" is wrong. subfic 10,10,4 # tmp160, tmp159, looks wrong, if replaced by subfic 10,10,2 # tmp160, tmp159, the code works correctly $ powerpc64le-unknown-linux-gnu-gcc -v Using built-in specs. COLLECT_GCC=/repo/gcc-trunk/binary-latest-powerpc64le/bin/powerpc64le-unknown-linux-gnu-gcc COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-r12-2049-20210706092228-gb019b28ebd6-checking-yes-rtl-df-extra-powerpc64le/bin/../libexec/gcc/powerpc64le-unknown-linux-gnu/12.0.0/lto-wrapper Target: powerpc64le-unknown-linux-gnu Configured with: /repo/gcc-trunk//configure --enable-languages=c,c++ --enable-valgrind-annotations --disable-nls --enable-checking=yes,rtl,df,extra --with-cloog --with-ppl --with-isl --with-sysroot=/usr/powerpc64le-unknown-linux-gnu --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --target=powerpc64le-unknown-linux-gnu --with-ld=/usr/bin/powerpc64le-unknown-linux-gnu-ld --with-as=/usr/bin/powerpc64le-unknown-linux-gnu-as --disable-libstdcxx-pch --prefix=/repo/gcc-trunk//binary-trunk-r12-2049-20210706092228-gb019b28ebd6-checking-yes-rtl-df-extra-powerpc64le Thread model: posix Supported LTO compression algorithms: zlib zstd gcc version 12.0.0 20210706 (experimental) (GCC)