[g-arc-opts] Only run the ARC optimizer on functions that contain reference count instructions that we care about.
[g-arc-opts] Only run the ARC optimizer on functions that contain reference count instructions that we care about.

This shaves off another second or so from the runtime of swift on bst.swift.

<rdar://problem/17181185>

Swift SVN r18727

johnno1962d/swift,deyton/swift,ben-ng/swift,jopamer/swift,cbrentharris/swift,xedin/swift,gregomni/swift,roambotics/swift,frootloops/swift,felix91gr/swift,apple/swift,tinysun212/swift-windows,aschwaighofer/swift,swiftix/swift.old,Jnosh/swift,Ivacker/swift,aschwaighofer/swift,nathawes/swift,xedin/swift,JaSpa/swift,xwu/swift,kusl/swift,russbishop/swift,shahmishal/swift,frootloops/swift,russbishop/swift,xwu/swift,milseman/swift,KrishMunot/swift,allevato/swift,amraboelela/swift,kperryua/swift,IngmarStein/swift,harlanhaskins/swift,OscarSwanros/swift,benlangmuir/swift,russbishop/swift,CodaFi/swift,johnno1962d/swift,slavapestov/swift,aschwaighofer/swift,adrfer/swift,ken0nek/swift,emilstahl/swift,ahoppen/swift,roambotics/swift,hooman/swift,SwiftAndroid/swift,therealbnut/swift,tjw/swift,return/swift,alblue/swift,arvedviehweger/swift,Jnosh/swift,parkera/swift,zisko/swift,ben-ng/swift,sdulal/swift,JaSpa/swift,aschwaighofer/swift,jmgc/swift,karwa/swift,calebd/swift,MukeshKumarS/Swift,ahoppen/swift,kstaring/swift,apple/swift,amraboelela/swift,gottesmm/swift,jtbandes/swift,gribozavr/swift,swiftix/swift.old,modocache/swift,return/swift,OscarSwanros/swift,adrfer/swift,calebd/swift,stephentyrone/swift,danielmartin/swift,IngmarStein/swift,huonw/swift,CodaFi/swift,adrfer/swift,allevato/swift,arvedviehweger/swift,sschiau/swift,kentya6/swift,cbrentharris/swift,natecook1000/swift,jmgc/swift,zisko/swift,therealbnut/swift,Jnosh/swift,gribozavr/swift,dduan/swift,austinzheng/swift,ben-ng/swift,atrick/swift,sdulal/swift,dreamsxin/swift,bitjammer/swift,devincoughlin/swift,kusl/swift,nathawes/swift,zisko/swift,amraboelela/swift,apple/swift,LeoShimonaka/swift,bitjammer/swift,huonw/swift,devincoughlin/swift,mightydeveloper/swift,sschiau/swift,bitjammer/swift,parkera/swift,practicalswift/swift,LeoShimonaka/swift,khizkhiz/swift,stephentyrone/swift,parkera/swift,mightydeveloper/swift,Jnosh/swift,xwu/swift,zisko/swift,roambotics/swift,hughbe/swift,uasys/swift,parkera/swift,benlangmuir/swift,danielmartin/swift,russbishop/swift,practicalswift/swift,OscarSwanros/swift,gottesmm/swift,gribozavr/swift,harlanhaskins/swift,gmilos/swift,brentdax/swift,manavgabhawala/swift,slavapestov/swift,gmilos/swift,sschiau/swift,ken0nek/swift,felix91gr/swift,xedin/swift,lorentey/swift,russbishop/swift,shajrawi/swift,jmgc/swift,OscarSwanros/swift,emilstahl/swift,swiftix/swift.old,bitjammer/swift,swiftix/swift.old,SwiftAndroid/swift,tinysun212/swift-windows,xedin/swift,therealbnut/swift,gmilos/swift,khizkhiz/swift,gottesmm/swift,jckarter/swift,brentdax/swift,jtbandes/swift,calebd/swift,swiftix/swift,deyton/swift,ken0nek/swift,hooman/swift,danielmartin/swift,milseman/swift,karwa/swift,milseman/swift,allevato/swift,lorentey/swift,jckarter/swift,ben-ng/swift,Jnosh/swift,sdulal/swift,xedin/swift,IngmarStein/swift,aschwaighofer/swift,ken0nek/swift,jopamer/swift,johnno1962d/swift,alblue/swift,codestergit/swift,hughbe/swift,therealbnut/swift,parkera/swift,deyton/swift,kstaring/swift,sschiau/swift,hooman/swift,practicalswift/swift,manavgabhawala/swift,rudkx/swift,natecook1000/swift,Jnosh/swift,return/swift,sschiau/swift,OscarSwanros/swift,brentdax/swift,tinysun212/swift-windows,kusl/swift,shajrawi/swift,mightydeveloper/swift,rudkx/swift,jmgc/swift,airspeedswift/swift,swiftix/swift,deyton/swift,Ivacker/swift,shajrawi/swift,uasys/swift,karwa/swift,tjw/swift,CodaFi/swift,kusl/swift,tkremenek/swift,karwa/swift,kperryua/swift,alblue/swift,jtbandes/swift,allevato/swift,gregomni/swift,MukeshKumarS/Swift,sdulal/swift,calebd/swift,kusl/swift,johnno1962d/swift,tkremenek/swift,hughbe/swift,djwbrown/swift,apple/swift,gregomni/swift,gribozavr/swift,huonw/swift,sdulal/swift,atrick/swift,alblue/swift,swiftix/swift,hughbe/swift,huonw/swift,emilstahl/swift,alblue/swift,uasys/swift,practicalswift/swift,atrick/swift,adrfer/swift,modocache/swift,tinysun212/swift-windows,cbrentharris/swift,SwiftAndroid/swift,atrick/swift,kentya6/swift,JGiola/swift,djwbrown/swift,jckarter/swift,manavgabhawala/swift,khizkhiz/swift,tkremenek/swift,CodaFi/swift,KrishMunot/swift,jmgc/swift,IngmarStein/swift,tardieu/swift,modocache/swift,lorentey/swift,glessard/swift,parkera/swift,cbrentharris/swift,xwu/swift,gmilos/swift,kperryua/swift,dduan/swift,jopamer/swift,natecook1000/swift,xedin/swift,practicalswift/swift,danielmartin/swift,return/swift,khizkhiz/swift,russbishop/swift,jtbandes/swift,gregomni/swift,KrishMunot/swift,shahmishal/swift,shahmishal/swift,slavapestov/swift,deyton/swift,jckarter/swift,harlanhaskins/swift,karwa/swift,lorentey/swift,glessard/swift,codestergit/swift,swiftix/swift,austinzheng/swift,ahoppen/swift,arvedviehweger/swift,kusl/swift,arvedviehweger/swift,tjw/swift,deyton/swift,LeoShimonaka/swift,tkremenek/swift,ahoppen/swift,deyton/swift,benlangmuir/swift,sdulal/swift,shahmishal/swift,dreamsxin/swift,swiftix/swift.old,rudkx/swift,practicalswift/swift,cbrentharris/swift,danielmartin/swift,therealbnut/swift,swiftix/swift.old,zisko/swift,djwbrown/swift,johnno1962d/swift,austinzheng/swift,benlangmuir/swift,calebd/swift,shahmishal/swift,hooman/swift,felix91gr/swift,natecook1000/swift,airspeedswift/swift,slavapestov/swift,adrfer/swift,danielmartin/swift,airspeedswift/swift,LeoShimonaka/swift,Ivacker/swift,amraboelela/swift,hughbe/swift,glessard/swift,roambotics/swift,modocache/swift,kstaring/swift,codestergit/swift,IngmarStein/swift,emilstahl/swift,jopamer/swift,shahmishal/swift,stephentyrone/swift,rudkx/swift,devincoughlin/swift,JGiola/swift,benlangmuir/swift,slavapestov/swift,kstaring/swift,Ivacker/swift,zisko/swift,swiftix/swift,MukeshKumarS/Swift,mightydeveloper/swift,hooman/swift,lorentey/swift,hughbe/swift,ken0nek/swift,tardieu/swift,arvedviehweger/swift,karwa/swift,gregomni/swift,dduan/swift,lorentey/swift,milseman/swift,uasys/swift,manavgabhawala/swift,devincoughlin/swift,sschiau/swift,dduan/swift,MukeshKumarS/Swift,dduan/swift,glessard/swift,stephentyrone/swift,Ivacker/swift,IngmarStein/swift,airspeedswift/swift,xedin/swift,swiftix/swift,JaSpa/swift,tinysun212/swift-windows,practicalswift/swift,jmgc/swift,OscarSwanros/swift,benlangmuir/swift,LeoShimonaka/swift,alblue/swift,khizkhiz/swift,shajrawi/swift,cbrentharris/swift,kusl/swift,manavgabhawala/swift,MukeshKumarS/Swift,mightydeveloper/swift,JaSpa/swift,austinzheng/swift,return/swift,tkremenek/swift,kperryua/swift,CodaFi/swift,kentya6/swift,mightydeveloper/swift,gribozavr/swift,kentya6/swift,JaSpa/swift,harlanhaskins/swift,apple/swift,gribozavr/swift,gmilos/swift,adrfer/swift,xwu/swift,gottesmm/swift,shajrawi/swift,stephentyrone/swift,shajrawi/swift,djwbrown/swift,felix91gr/swift,tardieu/swift,JaSpa/swift,amraboelela/swift,nathawes/swift,manavgabhawala/swift,swiftix/swift,kentya6/swift,glessard/swift,brentdax/swift,rudkx/swift,MukeshKumarS/Swift,karwa/swift,JaSpa/swift,KrishMunot/swift,huonw/swift,djwbrown/swift,jckarter/swift,return/swift,khizkhiz/swift,hughbe/swift,frootloops/swift,ahoppen/swift,nathawes/swift,MukeshKumarS/Swift,lorentey/swift,emilstahl/swift,lorentey/swift,adrfer/swift,shahmishal/swift,natecook1000/swift,calebd/swift,Jnosh/swift,jtbandes/swift,alblue/swift,mightydeveloper/swift,airspeedswift/swift,glessard/swift,arvedviehweger/swift,hooman/swift,milseman/swift,nathawes/swift,jopamer/swift,jopamer/swift,zisko/swift,gmilos/swift,austinzheng/swift,kperryua/swift,aschwaighofer/swift,khizkhiz/swift,ben-ng/swift,devincoughlin/swift,uasys/swift,tkremenek/swift,slavapestov/swift,devincoughlin/swift,gottesmm/swift,gottesmm/swift,johnno1962d/swift,jtbandes/swift,codestergit/swift,manavgabhawala/swift,kstaring/swift,shajrawi/swift,harlanhaskins/swift,felix91gr/swift,kstaring/swift,austinzheng/swift,tjw/swift,SwiftAndroid/swift,aschwaighofer/swift,xedin/swift,brentdax/swift,uasys/swift,kperryua/swift,sdulal/swift,devincoughlin/swift,Ivacker/swift,harlanhaskins/swift,kentya6/swift,atrick/swift,sdulal/swift,SwiftAndroid/swift,johnno1962d/swift,devincoughlin/swift,tjw/swift,JGiola/swift,airspeedswift/swift,danielmartin/swift,practicalswift/swift,tardieu/swift,Ivacker/swift,huonw/swift,austinzheng/swift,ben-ng/swift,bitjammer/swift,natecook1000/swift,allevato/swift,dduan/swift,frootloops/swift,emilstahl/swift,arvedviehweger/swift,bitjammer/swift,ken0nek/swift,sschiau/swift,JGiola/swift,felix91gr/swift,parkera/swift,gregomni/swift,xwu/swift,tardieu/swift,modocache/swift,return/swift,sschiau/swift,tjw/swift,emilstahl/swift,KrishMunot/swift,CodaFi/swift,gribozavr/swift,KrishMunot/swift,tkremenek/swift,allevato/swift,amraboelela/swift,SwiftAndroid/swift,calebd/swift,jckarter/swift,frootloops/swift,LeoShimonaka/swift,stephentyrone/swift,roambotics/swift,swiftix/swift.old,harlanhaskins/swift,shajrawi/swift,slavapestov/swift,therealbnut/swift,dduan/swift,emilstahl/swift,tjw/swift,brentdax/swift,gottesmm/swift,hooman/swift,frootloops/swift,ken0nek/swift,tardieu/swift,mightydeveloper/swift,SwiftAndroid/swift,swiftix/swift.old,jtbandes/swift,kentya6/swift,codestergit/swift,IngmarStein/swift,tinysun212/swift-windows,LeoShimonaka/swift,natecook1000/swift,parkera/swift,uasys/swift,KrishMunot/swift,LeoShimonaka/swift,cbrentharris/swift,gmilos/swift,milseman/swift,apple/swift,cbrentharris/swift,huonw/swift,OscarSwanros/swift,CodaFi/swift,kentya6/swift,kperryua/swift,tardieu/swift,bitjammer/swift,codestergit/swift,jopamer/swift,felix91gr/swift,kusl/swift,djwbrown/swift,djwbrown/swift,nathawes/swift,frootloops/swift,stephentyrone/swift,shahmishal/swift,ahoppen/swift,karwa/swift,gribozavr/swift,brentdax/swift,jmgc/swift,roambotics/swift,atrick/swift,amraboelela/swift,kstaring/swift,modocache/swift,JGiola/swift,russbishop/swift,tinysun212/swift-windows,rudkx/swift,nathawes/swift,Ivacker/swift,jckarter/swift,xwu/swift,modocache/swift,ben-ng/swift,allevato/swift,milseman/swift,therealbnut/swift,airspeedswift/swift,JGiola/swift,codestergit/swift