[Bug target/52692] New: [avr]: Add support for avr-specific built-ins + LTO

["gjl at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52692

             Bug #: 52692
           Summary: [avr]: Add support for avr-specific built-ins + LTO
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: gjl@gcc.gnu.org
                CC: eric.weddington@atmel.com
            Target: avr


Implement TARGET_BUILTIN_DECL so that the following works:

int main (void) 
{ 
    __builtin_avr_delay_cycles (1000); 
    return 0; 
}

Currently, this prints

$ avr-gcc main.c -S -flto

main.c:7:1: sorry, unimplemented: tree bytecode streams do not support machine
specific builtin functions on this target