AllocBoxToStack: Don't promote if there's no "last release".
AllocBoxToStack: Don't promote if there's no "last release".

An unbalanced alloc_stack without a matching dealloc_stack doesn't pass muster with the verifier anymore.

Swift SVN r9132

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