Re: RFC: Speeding up libstdc++.so with --dynamic-list-data

[Andrew Haley <aph at redhat dot com>]

H. J. Lu writes:
 > On Tue, Jan 09, 2007 at 01:38:00PM +0000, Andrew Haley wrote:
 > > H. J. Lu writes:
 > >  > I am enclosing a patch to implement a new linker swicth,
 > >  > --dynamic-list-data. It is -Bsymbolic for function symbols only.
 > >  > I tried it with C, C++, Java and Fortran on Linux/ia32, Linux/x86-64
 > >  > and Linux/ia64. There are only a few regressions. The function calls
 > >  > within the new resulting DSOs will bind locally. It speeds up
 > >  > the enclosed C++ testcase by
 > >  > 
 > >  > 1. 23% on ia64.
 > >  > 2. 6% on ia32.
 > >  > 3. 3% on x86-64.
 > >  > 
 > >  > Should we consider such optimization?
 > > 
 > > That's a terrible name for the option.  What does it mean?
 > 
 > It is an extension of the current command line options:
 > 
 >   --dynamic-list-cpp-typeinfo Use C++ typeinfo dynamic list
 >   --dynamic-list FILE         Read dynamic list

But you said it was like -Bsymbolic for function symbols only.  What
is the connection between C++ typeinfo and that?  (Hint: Java doesn't
use C++ typeinfo, but -Bsymbolic for function symbols only would be
very useful.)

Andrew.