middle-end: check that the lhs of a COND_EXPR is an SSA_NAME in cond_store recognition [PR116628]
Because the vect_recog_bool_pattern can at the moment still transition
out of GIMPLE and back into GENERIC the vect_recog_cond_store_pattern can
end up using an expression as a mask rather than an SSA_NAME.
This adds an explicit check that we have a mask and not an expression.
gcc/ChangeLog:
PR tree-optimization/116628
* tree-vect-patterns.cc (vect_recog_cond_store_pattern): Add SSA_NAME
check on expression.
gcc/testsuite/ChangeLog:
PR tree-optimization/116628
* gcc.dg/vect/pr116628.c: New test.