In i386.c, there are
if (optimize_size)
ix86_cost = &size_cost;
else
ix86_cost = processor_target_table[ix86_tune].cost;
...
ix86_branch_cost = processor_target_table[ix86_tune].cost->branch_cost;
As the result, -Os may generate bigger code than it should have.
--
Summary: Branch cost of -Os is ignored
Product: gcc
Version: 4.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P2
Component: target
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: hjl at lucon dot org
GCC build triplet: i686-pc-linux-gnu
GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24547
