[Bug tree-optimization/117379] Failure to vectorize multi add + mulit sub

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117379

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
We are correctly detecting the reduction chain in vect_slp_check_for_roots but
currently reject mixed operation chains there:

                  if (chain[i].code != code)
                    {
                      invalid = true;
                      break;
                    }

(gdb) p chain.length ()
$1 = 8
(gdb) p chain
$2 = {<vec<chain_op_t, va_heap, vl_ptr>> = {m_vec = 0x4d957a0 = {{
        code = PLUS_EXPR, dt = vect_internal_def, 
        op = <ssa_name 0x7ffff6e1c000 4>}, {code = PLUS_EXPR, 
        dt = vect_internal_def, op = <ssa_name 0x7ffff700df30 3>}, {
        code = PLUS_EXPR, dt = vect_internal_def, 
        op = <ssa_name 0x7ffff700de10 1>}, {code = PLUS_EXPR, 
        dt = vect_internal_def, op = <ssa_name 0x7ffff700dea0 2>}, {
        code = MINUS_EXPR, dt = vect_internal_def, 
        op = <ssa_name 0x7ffff6e1c1f8 8>}, {code = MINUS_EXPR, 
        dt = vect_internal_def, op = <ssa_name 0x7ffff6e1c168 7>}, {
        code = MINUS_EXPR, dt = vect_internal_def, 
        op = <ssa_name 0x7ffff6e1c0d8 6>}, {code = MINUS_EXPR, 
        dt = vect_internal_def, 
        op = <ssa_name 0x7ffff6e1c048 5>}}}, <No data fields>}

mixed operation handling is missing in vectorize_slp_instance_root_stmt
and it misses meta-data to indicate which lanes to negate.