diff options
Diffstat (limited to 'gcc/tree-nrv.c')
| -rw-r--r-- | gcc/tree-nrv.c | 20 |
1 files changed, 9 insertions, 11 deletions
diff --git a/gcc/tree-nrv.c b/gcc/tree-nrv.c index b85c5a7..c2e49d3 100644 --- a/gcc/tree-nrv.c +++ b/gcc/tree-nrv.c @@ -291,23 +291,21 @@ struct gimple_opt_pass pass_nrv = optimization, where DEST is expected to be the LHS of a modify expression where the RHS is a function returning an aggregate. - We search for a base VAR_DECL and look to see if it is call clobbered. - Note that we could do better, for example, by - attempting to doing points-to analysis on INDIRECT_REFs. */ + DEST is available if it is not clobbered by the call. */ static bool -dest_safe_for_nrv_p (tree dest) +dest_safe_for_nrv_p (gimple call) { - while (handled_component_p (dest)) - dest = TREE_OPERAND (dest, 0); + tree dest = gimple_call_lhs (call); - if (! SSA_VAR_P (dest)) + dest = get_base_address (dest); + if (! dest) return false; if (TREE_CODE (dest) == SSA_NAME) - dest = SSA_NAME_VAR (dest); + return true; - if (is_call_clobbered (dest)) + if (call_may_clobber_ref_p (call, dest)) return false; return true; @@ -346,8 +344,8 @@ execute_return_slot_opt (void) ) { /* Check if the location being assigned to is - call-clobbered. */ - slot_opt_p = dest_safe_for_nrv_p (gimple_call_lhs (stmt)); + clobbered by the call. */ + slot_opt_p = dest_safe_for_nrv_p (stmt); gimple_call_set_return_slot_opt (stmt, slot_opt_p); } } |