I’m taking a look.
Thanks,
Kyrill
> On 15 Jun 2026, at 12:17, Haochen Jiang <[email protected]> wrote:
>
> On Linux/x86_64,
>
> 6bbe931ea0e8f412c81fed8a3df4a07df97821f4 is the first bad commit
> commit 6bbe931ea0e8f412c81fed8a3df4a07df97821f4
> Author: Kyrylo Tkachov <[email protected]>
> Date: Fri Jun 12 00:00:00 2026 +0000
>
> match.pd: fold (0/1) * -(0/1) into -((0/1) & (0/1))
>
> caused
>
> FAIL: g++.dg/tree-ssa/mult-negate-zeroone-1.C -std=gnu++20
> scan-tree-dump-not optimized " * "
> FAIL: g++.dg/tree-ssa/mult-negate-zeroone-1.C -std=gnu++26
> scan-tree-dump-not optimized " * "
> FAIL: g++.dg/tree-ssa/mult-negate-zeroone-1.C -std=gnu++98
> scan-tree-dump-not optimized " * "
>
> with GCC configured with
>
> ../../gcc/configure
> --prefix=/export/users3/haochenj/src/gcc-bisect/master/master/r17-1528/usr
> --enable-clocale=gnu --with-system-zlib --with-demangler-in-ld
> --with-fpmath=sse --enable-languages=c,c++,fortran --enable-cet --without-isl
> --enable-libmpx x86_64-linux --disable-bootstrap
>
> To reproduce:
>
> $ cd {build_dir}/gcc && make check
> RUNTESTFLAGS="dg.exp=g++.dg/tree-ssa/mult-negate-zeroone-1.C
> --target_board='unix{-m32}'"
> $ cd {build_dir}/gcc && make check
> RUNTESTFLAGS="dg.exp=g++.dg/tree-ssa/mult-negate-zeroone-1.C
> --target_board='unix{-m32\ -march=cascadelake}'"
> $ cd {build_dir}/gcc && make check
> RUNTESTFLAGS="dg.exp=g++.dg/tree-ssa/mult-negate-zeroone-1.C
> --target_board='unix{-m64}'"
> $ cd {build_dir}/gcc && make check
> RUNTESTFLAGS="dg.exp=g++.dg/tree-ssa/mult-negate-zeroone-1.C
> --target_board='unix{-m64\ -march=cascadelake}'"
>
> (Please directly reply to this email for question about this report.)
> (If you met problems with cascadelake related, disabling AVX512F in command
> line might save that.)
> (However, please make sure that there is no potential problems with AVX512.)
