On 28/03/10 15:45, Carrot Wei wrote: > Hi > > The detailed description of the optimization is at > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43129. This is an ARM > specific optimization. > > This optimization uses one less register (the register hold the GOT > base), to get this beneficial the ideal place for it should be before > register allocation. > > Usually expand pass generates instructions to load global variable's > address from GOT entry for each access of the global variable. Later > cse/gcse passes can remove many of them. In order to precisely model > the cost, this optimization should be put after some cse/gcse passes. > > So what is the best place for this optimization? Is there any existed > pass can be enhanced with this optimization? Or should I add a new > pass?
The obvious place is machine-dependent reorg, which is a very late pass. Andrew.
