This is the mail archive of the gcc@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Help porting to lra


I am trying to enable lra for my vliw architecture and I am encountering a problem of "max number of generated reload insns". The problem seems elementary but I don't see the correction.

Consider
     r1 =r2+r3
    s1=r1+r4
    call func(r3)
    r5=s2+r1

where s registers are pseudo registers which ira maps to callee saved registers and r registers are pseudo registers which ira maps to caller saved registers. The inheritance pass sees that r1 is still live across a call so it generates a spill using split_reg. Call_save_p is true so it spills to a pseudo register which ends up getting the same hard register assignment as r1. Therefore nothing is solved, the new register is also live across the call.

The call to the emit_spill_move looks like it is expecting a memory destination but it is in fact receiving a pseudo register. Did I miss some kind of hook that makes the spill go to the stack? Reload gets it right.

Thanks,
Shmeel


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]