[Bug tree-optimization/81661] [7/8 Regression] ICE in gimplify_modify_expr, at gimplify.c:5638

["jakub at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81661

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

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

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
So do we need some predicate that will tell us if it is safe to evaluate some
generic expression using force_gimple_operand* and bail out if it isn't
possible?
Even if gimplify_cond_expr tried harder around:
3865              if (gimplify_ctxp->allow_rhs_cond_expr
3866                  /* If either branch has side effects or could trap, it
can't be
3867                     evaluated unconditionally.  */
3868                  && !TREE_SIDE_EFFECTS (then_)
3869                  && !generic_expr_could_trap_p (then_)
3870                  && !TREE_SIDE_EFFECTS (else_)
3871                  && !generic_expr_could_trap_p (else_))
3872                return gimplify_pure_cond_expr (expr_p, pre_p);
3873    
3874              tmp = create_tmp_var (type, "iftmp");
and built for the case where gimplify_pure_cond_expr can't be used a SSA_NAME
and a PHI if we're in SSA, I guess the vast majority of callers of
force_gimple_operand* don't really expect that the sequence might need to be
split into several basic blocks.