clisp currently can't be compiled with optimization very well, because PTA
takes ages when presented with source code of the form clisp uses.
The attachment demonstrates this:
% /usr/lib/gcc/powerpc64-suse-linux/4.1.0/cc1 -O1 slow-pta.i
....
tree PTA : 18.08 (100%) usr 0.03 (75%) sys 18.11 (100%) wall
....
The code is trivial:
symbol_ *bla;
void slow (void) {
bla = &symbol_tab_data.S_nil;
}
The crux is the form of symbol_tab_data containing a large number of members,
each of them being a struct containing seven pointers. Making that latter
struct contain less members hugely decreases compile time.
--
Summary: PTA is slow with large structs (hits clisp)
Product: gcc
Version: 4.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: matz at suse dot de
GCC host triplet: ppc-linux
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26260
