void
update_stmt_operands (gimple stmt)
{
/* If update_stmt_operands is called before SSA is initialized, do
nothing. */
if (!ssa_operands_active ())
return;
timevar_push (TV_TREE_OPS);
/* If the stmt is a noreturn call queue it to be processed by
split_bbs_on_noreturn_calls during cfg cleanup. */
if (is_gimple_call (stmt)
&& gimple_call_noreturn_p (stmt))
VEC_safe_push (gimple, gc, MODIFIED_NORETURN_CALLS (cfun), stmt);
gcc_assert (gimple_modified_p (stmt));
build_ssa_operands (stmt);
gimple_set_modified (stmt, false);
timevar_pop (TV_TREE_OPS);
}
bool
gimple_stmt_may_fallthru (gimple *stmt)
{
if (!stmt)
return true;
switch (gimple_code (stmt))
{
case GIMPLE_GOTO:
case GIMPLE_RETURN:
case GIMPLE_RESX:
/* Easy cases. If the last statement of the seq implies
control transfer, then we can't fall through. */
return false;
case GIMPLE_SWITCH:
/* Switch has already been lowered and represents a branch
to a selected label and hence can't fall through. */
return false;
case GIMPLE_COND:
/* GIMPLE_COND's are already lowered into a two-way branch. They
can't fall through. */
return false;
case GIMPLE_BIND:
return gimple_seq_may_fallthru (
gimple_bind_body (as_a <gbind *> (stmt)));
case GIMPLE_TRY:
if (gimple_try_kind (stmt) == GIMPLE_TRY_CATCH)
return gimple_try_catch_may_fallthru (as_a <gtry *> (stmt));
/* It must be a GIMPLE_TRY_FINALLY. */
/* The finally clause is always executed after the try clause,
so if it does not fall through, then the try-finally will not
fall through. Otherwise, if the try clause does not fall
through, then when the finally clause falls through it will
resume execution wherever the try clause was going. So the
whole try-finally will only fall through if both the try
clause and the finally clause fall through. */
return (gimple_seq_may_fallthru (gimple_try_eval (stmt))
&& gimple_seq_may_fallthru (gimple_try_cleanup (stmt)));
case GIMPLE_EH_ELSE:
{
geh_else *eh_else_stmt = as_a <geh_else *> (stmt);
return (gimple_seq_may_fallthru (gimple_eh_else_n_body (eh_else_stmt))
|| gimple_seq_may_fallthru (gimple_eh_else_e_body (
eh_else_stmt)));
}
case GIMPLE_CALL:
/* Functions that do not return do not fall through. */
return !gimple_call_noreturn_p (stmt);
default:
return true;
}
}
