SimplifyCFG: sprinkle some verification on top
SimplifyCFG: sprinkle some verification on top

Verify the dominator tree at strategic points to make sure we don't regress this in the future

Swift SVN r26980

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