[Bug target/117955] GCC generate illegal riscv instruction `vsetvli zero,zero,e64,mf4,ta,ma` with -O2 and -O3

[rdapp at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117955

Robin Dapp <rdapp at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |rdapp at gcc dot gnu.org

--- Comment #7 from Robin Dapp <rdapp at gcc dot gnu.org> ---
Yes, it's a vsetvl issue.  We're merging

  e16,mf4,ta,ma

and

  e64,m1,ta,ma

into

  e64,mf4,ta,ma.

Jin Ma touched this fuse rule by including the ratio but we also need to
observe the LMUL value itself.  I'm testing a patch.