On Fri, Apr 26, 2024 at 5:44 AM Aldy Hernandez via Gcc <gcc@gcc.gnu.org> wrote: > > In implementing prange (pointer ranges), I have found a 1.74% slowdown > in VRP, even without any code path actually using the code. I have > tracked this down to irange::get_bitmask() being compiled differently > with and without the bare bones patch. With the patch, > irange::get_bitmask() has a lot of code inlined into it, particularly > get_bitmask_from_range() and consequently the wide_int_storage code. ... > +static irange_bitmask > +get_bitmask_from_range (tree type, > + const wide_int &min, const wide_int &max) ... > -irange_bitmask > -irange::get_bitmask_from_range () const
My guess is that this is the relevant change: the old function has external linkage, and is therefore interposable, which inhibits inlining. The new function has internal linkage, which allows inlining. Relatedly, I wonder if we want to build GCC with -fno-semantic-interposition? Jason
