Teach DCE to invalidate branches and calls only if changes were made.
Teach DCE to invalidate branches and calls only if changes were made.

Swift SVN r26549

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