diff options
Diffstat (limited to 'gcc/rtl-ssa/accesses.cc')
| -rw-r--r-- | gcc/rtl-ssa/accesses.cc | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/gcc/rtl-ssa/accesses.cc b/gcc/rtl-ssa/accesses.cc index 3d92997..0415e97 100644 --- a/gcc/rtl-ssa/accesses.cc +++ b/gcc/rtl-ssa/accesses.cc @@ -1087,6 +1087,38 @@ rtl_ssa::lookup_use (splay_tree<use_info *> &tree, insn_info *insn) return tree.lookup (compare); } +// See the comment above the declaration. +use_lookup +function_info::find_use (set_info *def, insn_info *insn) +{ + gcc_assert (!insn->is_debug_insn ()); + use_info *first = def->first_nondebug_insn_use (); + if (!first) + // There are no uses. The comparison result is pretty meaningless + // in this case. + return { nullptr, -1 }; + + // See whether the first use matches. + if (*insn <= *first->insn ()) + { + int comparison = (insn == first->insn () ? 0 : -1); + return { first, comparison }; + } + + // See whether the last use matches. + use_info *last = def->last_nondebug_insn_use (); + if (*insn >= *last->insn ()) + { + int comparison = (insn == last->insn () ? 0 : 1); + return { last, comparison }; + } + + // Resort to using a splay tree to search for the result. + need_use_splay_tree (def); + int comparison = lookup_use (def->m_use_tree, insn); + return { def->m_use_tree.root ()->value (), comparison }; +} + // Add USE to USE->def ()'s list of uses. inserting USE immediately before // BEFORE. USE is not currently in the list. // |